JP2024525057A - Body weight support walking exercise device - Google Patents

Abstract

The body weight-supported locomotion device includes a frame (11) configured to support locomotion motion and an offset assembly (140) carried by the frame (11). The offset assembly (140) includes a spring (141) having a fixed end (150) coupled to the frame (11) and an opposing free end (151), a cam assembly (142) mounted to the frame (11) for rotational motion, a first tether (143) extending from the free end (151) of the spring (141) to the cam assembly (142), and a second tether (144) extending from the cam assembly (142) to a load. The offset assembly (140) exerts an offset force on the load against the frame (11).

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to prior U.S. patent application Ser. No. 17/362,799, filed June 29, 2021, which is a continuation-in-part of and claims the benefit of prior U.S. patent application Ser. No. 17/160,221, filed January 27, 2021, which claims the benefit of U.S. Provisional Patent Application No. 62/967,011, filed January 28, 2020, all of which are incorporated herein by reference.

This specification relates generally to locomotor devices, and more specifically to locomotor rehabilitation, treatment, and training devices.

Locomotor movement is a fundamental aspect of human life. However, for some people, mobility can be difficult, harmful, or impossible. There are many reasons why a person may experience partial or complete mobility restrictions, including orthopedic conditions, neurological disorders, reduced mobility, accidents, injuries, diseases, and physical disabilities. Continuing to move, or even attempting to move, can cause discomfort or injury.

Some people may be injured or overweight, but need exercise to become healthier. Some rehabilitation facilities have sophisticated systems to partially support the weight of such patients so they can exercise toward health. The patient wears a harness that is tethered to a trolley that hangs from a track in the ceiling. Such systems are complex, require assistance from a physical therapist, and are very expensive, thus limiting patient availability. Some of these systems provide the lifting force through springs that change as the user moves and displaces the spring. Others have advanced sensing technology that monitors the patient's movements and then adjusts the lifting force to provide a constant unloading of the patient.

In some cases, movement may be possible and in fact easy, but the individual nevertheless wishes to reduce the risk of injury from such movement. For example, athletes are often required to train for long periods of time at a significant intensity. The athlete balances the benefits of high volume training with the increased risk of injury. After all, even minor injuries can cause serious physical and mental impairments for competitive athletes. Various assistive devices exist to reduce the chance of injury during exercise. For example, a runner may use a flotation device to run underwater. Alternatively, the runner can run on the treadmill in a zipped pressurized bag that elevates the runner slightly above the treadmill deck, thereby reducing the impact of foot strike.

Physiotherapists often have other devices that suspend and support the user from above while they move. For example, there are devices that can be placed on or above a treadmill, and usually include a harness, hooks, or special clothing that partially elevates the patient while walking or running on the treadmill. These devices exert an upward force on the patient while moving to reduce the patient's impact.

Naturally, all of these solutions offer insufficient freedom of movement. Users are restricted to predefined paths set in a pool, a treadmill, or a track on the ceiling. None of these can be used to, for example, get to the bathroom or walk around the neighborhood.

Moreover, and more seriously, each alters the normal movement patterns during walking and running. Harnesses suspended from a track in the ceiling generally support the user at a single location, usually above the head or near the center of the back. The harness may also lift the user on both sides of the hip joint. In either arrangement, the harness restricts the normal movement of the upper body during walking movements. The user may experience the same upward lift force on one side of the body as the other side of the body. In other words, the left and right sides of the user are lifted equally and simultaneously. However, in normal walking and running, the forces along the left side of the body are different and independent from the forces along the right side of the body. Such systems do not take these differences into account and exercise different muscles than those used in normal running and walking, which may lead to inappropriate or long-term rehabilitation, treatment, or training.

Furthermore, these systems exercise different muscles than those used in normal walking and running, which may lead to inappropriate or prolonged rehabilitation, therapy, or training. Use of these devices in rehabilitation, therapy, or training may not mimic real-world movements and may lead to inadequate recovery. Improved solutions are needed.

In one embodiment, a body weight-supported walking device includes a frame mounted on wheels for walking motion. The frame has opposing left and right sides, and a harness supports a user between the left and right sides. An unloading assembly is carried on each of the left and right sides, each of the unloading assemblies including a sprung arm having a fixed end fixed to the respective left and right side and an opposing free end. Each of the assemblies further includes a cam assembly attached to the free end of the sprung arm and a tether extending through the cam assembly to the harness. Each of the unloading assemblies thereby exerts an independent unloading force on the harness against the frame, promoting natural movement and allowing independent unloading of the left and right sides of the body during such natural movement.

In another embodiment, a body weight-supported walking device includes a frame for supporting walking motion. The frame has opposing left and right sides, and a harness supports a user between the left and right sides. An offset assembly is carried on each of the left and right sides. Each offset assembly includes a spring having a first end fixed to the respective left and right side and an opposing second end, a cam assembly, and a tether extending through the cam assembly to the harness. A cable extends through the cam assembly to one of an anchor on the frame and the second end of the spring. Each offset assembly exerts an independent offset force on the harness against the frame.

In yet another embodiment, a body weight-supported walking device includes a frame configured to support walking motion and an offset assembly carried by the frame. The offset assembly includes a spring having a fixed end and an opposing free end coupled to the frame, a cam assembly mounted to the frame for rotational motion, a first tether extending from the free end of the spring to the cam assembly, and a second tether extending from the cam assembly to a load. The offset assembly exerts an offset force on the load against the frame.

The above provides the reader with a very brief overview of some embodiments described below. Due to simplifications and omissions, the overview is not intended to limit or define the present disclosure in any way. Rather, this brief overview is merely intended to introduce the reader to some aspects of some embodiments as a prelude to the detailed description that follows.

With reference to the drawings:
FIG. 2 is a front perspective view of the body weight support walking exercise device. FIG. 2 is a side view of the body weight support walking exercise device. FIG. 2 is an enlarged side view of the body weight support walking exercise device with a panel removed to expose the support assembly carried thereon. 3 is a cross-sectional view of the body weight support walking apparatus and the support assembly carried thereon taken along line 3-3 of FIG. 1 with a small cutaway; 4 is a cross-sectional view taken along line 4-4 of FIG. 2, showing a pulley cassette on the body weight support walking apparatus. FIG. 2 is an enlarged rear perspective view of one of the pulley cassettes. FIG. 2 is an enlarged rear perspective view of one of the pulley cassettes. FIG. 13 is an enlarged schematic view showing an alternative embodiment of the relief assembly. FIG. 13 is an enlarged schematic view showing an alternative embodiment of the relief assembly. FIG. 13 is an enlarged schematic view showing an alternative embodiment of the relief assembly. FIG. 13 is an enlarged schematic view showing an alternative embodiment of the relief assembly. FIG. 13 is an enlarged schematic view showing an alternative embodiment of the relief assembly. FIG. 13 is an enlarged schematic view showing an alternative embodiment of the relief assembly. FIG. 13 is an enlarged schematic view showing an alternative embodiment of the relief assembly. FIG. 1 is a front view of a harness and its components for use in a body weight support walking device. FIG. 1 is a side view of a harness and its components for use in a body weight support walking exercise device. FIG. 1 is a perspective view of a harness and its components for use in a body weight support walking exercise device.

Reference is now made to the drawings, in which the same reference numbers are used throughout different drawings to denote the same elements. In brief, the embodiments presented herein are preferred exemplary embodiments and are not intended to limit the scope, applicability, or configuration of all possible embodiments, but rather to provide a possible description of all possible embodiments within the scope and spirit of the present specification. The description of these preferred embodiments is generally made using verbs such as "is and are" rather than "may, could," "includes, comprises," etc., as the description is made with reference to the drawings presented. Those skilled in the art will understand that changes may be made in the structure, arrangement, number, and function of elements and features without departing from the scope and spirit of the present specification. Furthermore, the description may omit certain information readily known to those skilled in the art to prevent obfuscating the description with details not necessary for operability. Indeed, the language used herein is meant to be readable and informative, rather than descriptive and limiting, of the present specification. Therefore, the scope and spirit of this specification should not be limited by the following description and its language choices.

1 and 2 are front perspective and right side views of a body weight relief walking exercise device 10 (hereinafter "device 10") for support during movement independent of different independent movements of both sides of the body. Device 10 provides independent bilateral support proximate to the hip joints of a user to assist the user in self-propelled walking motion. Device 10 includes an assembled frame 11, four wheels 12, and relief assemblies 13 and 14 carried by frame 11. Relief assemblies 13 and 14 are hidden by a panel 15 carried on frame 11 in Figs. 1 and 2, but are much more visible in Figs. 3A and 3B. Relief assemblies 13 and 14 are coupled to a harness worn by the user as shown in Fig. 1 and operate to lift or relieve a portion of the user's body weight on the left and right sides of the user's body.

The device 10 generally has a top 16, an opposing bottom 17, a front 18, and an opposing rear 19. The word "generally" is used herein to indicate a general area of the device 10, rather than specific points, elements, features, etc. Additionally, descriptions herein may be made in terms of relative directions or orientations with respect to these terms top, bottom, front, rear, and descriptions may indicate the placement of multiple elements or features relative to one another in the context of above, below, front, rear, etc., relying on the reader's understanding of the top 16, bottom 17, front 18, and rear 19 for contextual reference.

The frame 11 includes identical left and right sides 20 and 21 rigidly joined together by a top tube 22 and a bottom tube 23. Because the left and right sides 20 and 21 of the frame 11 are identical, only one will be described herein with the understanding that the description applies equally to the other. The same reference numbers are used for structural elements and features of both the left and right sides 20 and 21, and the reader will understand that the context or wording of the relevant description will convey whether the description is of the left or right side 20 or 21.

The right side 21 includes a main tube 24 that extends generally diagonally from the bottom 17 and rear 19 of the device 10, approximately midway between the top 16 and bottom 17 of the device 10, to a bottom tube 23 of the frame 11 adjacent the front 18. The main tube 24 has a rectangular cross-section, is hollow, and has thin, strong, durable, yet lightweight sidewalls constructed from a material or combination of materials having those properties, such as steel, aluminum, titanium, or carbon fiber. Other suitable construction materials and cross-sections are within the scope of this description.

The main tube 24 is connected to a vertical tube or housing 25 that rises from the main tube 24 near the rear 19 of the device 10. The housing 25 is cylindrical, but hollow like the main tube 24. The housing 25 holds a portion of the load-relief assembly, as described below.

The front tube 26 extends diagonally downward in the opposite direction to the main tube 24. The front tube 26 has a generally but not completely horizontal upper section, a long diagonal middle section, and a generally vertical lower section. The upper rear of the front tube 26 is connected to the top of the housing 25, and the middle of the front tube 26 is connected to the front of the main tube 24. The front tube 26, like the main tube 24, is preferably, but not necessarily, of rectangular cross section, is hollow, and has thin, strong, durable, yet lightweight sidewalls constructed from a material or combination of materials having those properties, such as steel, aluminum, titanium, or carbon fiber.

The bottoms of the main tube 24 and front tube 26 are generally vertical. The bottom of the front tube 26 is open to receive the post 30. The wheels 12 are mounted to the post 30 for rolling and pivoting motion so that the device 10 can be moved in a desired direction. The post 30 is formed with a series of vertically spaced holes 31, and an adjustment knob 32 is threaded through the bottom of the front tube 26 into one of the holes 31. The knob 32 allows the post 30 to be adjusted vertically to change the height of the device 10 at the front 18; the knob 32 can be loosened or released from the front tube 26 to slide the post 30 up or down, and then the knob 32 can be tightened or re-engaged to the front tube 26.

The bottom of the main tube 24 has a series of vertically spaced holes 33 formed therethrough. These holes 33 receive an axle 34 for each of the wheels 12 at the rear 19 of the device 10. The axles 34 can be moved to any of the holes 33 to adjust the height of the device 10 at the rear 19. The axles 34 are secured with pins 35, such as cotter pins or other suitable engagements, disposed through the axles 34 on the opposite side of the main tube 24 to the wheels 12. The wheels 12 at the rear 19 are preferably, but not necessarily, mounted for rolling motion but not for pivoting motion.

The left side 20 and right side 21 of the frame 11 are joined by a top tube 22 and a bottom tube 23. The top tube 22 is a rigid tube bent into a U-shape with a straight front section and two side sections or legs oriented at approximately 90 degrees to the front section. These legs are screwed, bolted, welded, or otherwise securely engaged to the top section of the front tube 26 of both the left side 20 and right side 21. Similarly, the bottom tube 23 is a rigid tube bent into a U-shape with a straight front section and two side sections or legs oriented at approximately 90 degrees to the front section. These legs are screwed, bolted, welded, or otherwise securely engaged to the top section of the main tube 24 of both the left side 20 and right side 21.

When a user uses the device 10, the user stands, walks, or runs behind the top tube 22 and bottom tube 23 and between the left side 20 and right side 21, as shown in FIG. 1. Thus, the top tube 22, together with the left side 20 and right side 21 and bottom tube 23, define a user receiving area 36 accessible from the rear 19 of the device 10.

The handlebars 40 extend forward at the top 16 of the device 10. A cylindrical sleeve 41 is attached along the top section of the front tube 26, the sleeve 41 being hollow and fixed at its rear to the top of the housing 25 and open at its front. The outside of the sleeve 41 is formed with a series of horizontally spaced holes 42 into which adjustment knobs 43 are threaded to allow the handlebars 40 to be adjusted horizontally to change the user's reach when using the device 10. The knobs 43 can be loosened or released from the sleeve 41 to slide the handlebars 40 in or out of the sleeve, and then the knobs 43 can be tightened or re-engaged with the sleeve 41.

The handlebar 40 is curved in several different directions. The rear of the handlebar 40 is straight so that it can fit into the sleeve 41. The handlebar 40 has a length such that it extends forward over the top section of the front tube 26, as shown in FIG. 1. The handlebar 40 then bends inward for a short section and then bends upward for a short section. Other handlebar 40 configurations are also suitable.

The handlebar 40 is hollow and has thin, strong, durable, yet lightweight side walls constructed from a material or combination of materials having those properties, such as steel, aluminum, titanium, or carbon fiber. When a user is positioned in the user receiving area 36 to operate the device 10, the user can easily reach out and hold the handlebar 40, and grasp any part of it as is comfortable to stabilize the device 10 and assist in movement and steering.

3A and 3B show the right side 21 of the frame 11. In 3A, the panel 15 has been removed to reveal the relief assembly 14, and 3B is a cross-sectional view taken along line 3-3 in 3A, slightly inside the frame 11, such that the panel 15 is not visible and the frame 11 is partially cut away. The relief assemblies 13 and 14 are carried on and partially within the frame 11, with the relief assembly 13 on the left side 20 and the relief assembly 14 on the right side 21. Again, as described above with respect to the left side 20 and right side 21, the relief assemblies 13 and 14 shown here are identical, and therefore only the relief assembly 14 on the right side 21 will be described here, with the understanding that the description applies equally to the other. The same reference numerals are also applicable to the relief assembly 14 on the left side 20. However, it should be understood that the relief assemblies 13 and 14 do not have to be identical, and this description should not be so limited. Indeed, in some embodiments, it may be desirable to actually have different relief assemblies. For example, if a user suffers from asymmetric weakness, the device 10 may be equipped with purposefully different unloading assemblies 13 and 14 having different bending, loading, and other performance characteristics. For example, in the case of a patient recovering from a stroke, it may be advantageous to provide more unloading force to the side of the patient's body more severely affected by the stroke and less unloading force to the other side. Nevertheless, for purposes of explanation in conjunction with the figures, these particular unloading assemblies 13 and 14 are identical.

The load-relief assembly 14 includes a leaf spring 50, a stacking cam assembly 51 on the leaf spring 50, a cable or tether 52 passing through the stacking cam assembly 51, and a series of pulleys attached to the frame 11.

The leaf spring 50 is a sprung arm, a lightweight, compact, elastic, elongated leaf spring member having a first fixed end 53 and a second free end 54. The fixed end 53 is fixed in a sleeve attached to a block 55 having an inclined surface 56. The adjustment knob 57 passes through a hole in the fixed end and enters a threaded hole 58 in the block 55. The adjustment knob 57 is thereby threadably engaged with the block 55 and can be tightened and loosened to change the spring force of the leaf spring 50. To decrease the spring force, the adjustment knob 57 is loosened and retracted from the bore 58 to allow the fixed end 53 to rise slightly away from the inclined surface 56 of the block 55. To increase the spring force, the adjustment knob 57 is tightened into the bore 58 to hold the fixed end 53 close to the inclined surface 56 of the block 55. The adjustment knob 57 is a means for adjusting the spring force of the leaf spring 50, and in other embodiments, the adjustment knob 57 can be an electrical, electromechanical or electromagnetic adjustment device, or an adjustable bolt, or some other means for changing the spring force.

In effect, the leaf spring 50 operates as a spring. The leaf spring 50 is mounted in a horizontal configuration, with the free end 54 above and behind the fixed end 53, and moves between a first "unloaded" position as shown in FIG. 3A, where the free end 54 is in a high position above the fixed end 53, and a second loaded position as shown in FIG. 3B, where the free end 54 is in a low position closer to the main tube 24. This movement is indicated by the arcuate double-arrow line A in FIG. 3B. The free end 54 moves toward the loaded position as the user steps and weights the harness on the right side 21, such as by pulling the leaf spring 50 downward via the tether 52. In response, the leaf spring 50 exerts a biasing force in a direction opposite to the pull of gravity, vertically translating the body downward during walking movements, and the leaf spring 50 acts to pull back on the tether 52. Other horizontal configurations are possible and may be suitable, including configurations that are vertically or horizontally inverted relative to the configuration described above. However, in general, a horizontal configuration is defined as one in which the spring (in this case, spring arms 50) extends horizontally.

Thus, the leaf spring 50 is simply a spring that exerts a biasing force against the displacement of the spring, either extension or compression. And in this sense, other springs such as coil springs, air springs, torsion springs, etc. may be suitable. The leaf spring 50 has a non-linear force-displacement curve such that as the displacement increases, the force required to displace the leaf spring 50 increases, and at greater displacements, more force is required to displace the free end 54 the same amount. The leaf spring 50 exerts a biasing force against its curvature, toward the front 18 of the device 10. Thus, when the user is moving forward, this forward bias also assists in moving the device 10 forward.

The stack cam assembly 51 is mounted for rotation at the free end 54. The stack cam assembly 51 includes an outer cam 60 and an inner cam 61 disposed side-by-side at the free end 54. Both cams 60 and 61 are mounted for rotation relative to one another about the same axis of rotation, but the cams 60 and 61 are fixed to one another to prevent relative rotation.

The outer cam 60 is larger and the inner cam 61 is smaller. Both cams 60 and 61 are eccentrics with different profiles or shapes, and the rotation axes of these cams are offset from their respective geometric centers so that when these cams rotate, their lever arms change and the ratio of their respective lever arms changes. In this way, with the tether 52 wrapped around the groove formed in the outer cam 61 and the tether 62 wrapped around the groove formed in the inner cam 60, the leaf spring 50 and the cam assembly 51 together form a constant force displacement system. In other words, beyond a certain preloaded displacement, additional displacement does not significantly change the force required for continued displacement. This is explained in more detail below. Furthermore, in other embodiments of the device 10, combinations of different cams are used, including assemblies with three or more cams, cams of different sizes than those presented herein, cams of similar sizes, etc. It should be noted that in this specification, the word "cam" includes rotating wheels and eccentrically mounted wheels or eccentric wheels. A cam is a mechanical element that converts rotational and translational motion. For the purposes of this description, a cam is a wheel, pulley, or other rotating element that is preferably, but not necessarily, eccentrically mounted. Eccentric rotation is the rotation of an element about an axis that is offset from the geometric center of the element. Thus, the shape or contour of the element's periphery may define the element as a cam, or the location of the axis of rotation may define the element as a cam. All of these definitions are considered within the scope of this disclosure for all embodiments described herein, without exception.

Another tether, an inelastic anchor cable 62, is tied between the inner cam 61 and the tie-down 63. This anchor cable 62 is part of the load-relief assembly 14. The tie-down 63 is an anchor that prevents the end of the anchor cable 62 attached to it from moving, and the other end of the anchor cable 62 is fixed to the inner cam 61. A pulley assembly including three pulleys 64, 65, and 66 is attached to the top of the main tube 24. One end of the anchor cable 62 is fixed to the top of the front of the inner cam 61 and sits in a groove therein, then extends down to the pulley 64. Rotation of the inner cam 61 causes the anchor cable 62 to wrap around the circumference of the inner cam 61, effectively shortening the anchor cable 62 and deflecting the leaf spring 50 towards the loaded position. The length of the anchor cable 62 can be adjusted with the tie-down 63 to increase or decrease the preload on the leaf spring 50.

The tether 52 has an opposite orientation on the larger outer cam 60. The tether 52 has two ends. One end of the tether 52 is fixed to the front side of the cam 60, which end is wrapped around the top of the cam 60, but in a different orientation than the anchor cable 62, so that one end of the tether 52 is fixed to the front side of the cam 60 and then extends to and around the cam 60. From there, the tether 52 extends downward to pulleys 65 and 66. The pulley 66 is partially attached inside the housing 25. When the tether 52 passes under the pulley 65, the tether is redirected from a nearly vertical orientation to a nearly horizontal orientation, and when the tether 52 passes under the pulley 66, the tether is redirected from a nearly horizontal orientation to a nearly vertical orientation inside the hollow housing 25.

The three pulleys 64, 65, and 66 have parallel axes and each rotate in the same direction. All three pulleys 64, 65, and 66 are mounted adjacent to one another in the same plane along the main tube 24, and therefore act only to redirect the anchor cable 62 or tether 52 along that plane. However, the tether 52 rises from pulley 66 inside the housing 25 to a different set of pulleys that directs the tether 52 for attachment to the harness.

4A-4C show the pulley cassette 70, including these other pulleys 71, 72, and 73 that redirect the tether 52. The pulley cassette 70 is part of the load-relieving assembly 13 (or 14), and includes an outer housing 74 to which the frame 11 is mounted for swinging movement within the housing 25, and having an inner side 75 and an opposing outer side 76. The outer side 76 faces inwardly, away from the frame 11, into the user receiving area 36. The inner side 75 is partially supported within the housing 25. Proximate the top 16, the housing 25 has a large open window 80. The pulley cassette 70 swings forward and backward within this window 80. Two disks 81 and 82 are fixed within the housing 25, disk 81 proximate the top 16 and disk 82 slightly below. A pin 83 extends coaxially between disks 81 and 82. A leaf is secured to the inside 75 of the pulley cassette 70 by a knuckle 84. The knuckle 84 has a vertical bore that is loosely attached to a pin 83. This allows the knuckle 84 to pivot about the pin 83, causing the pulley cassette 70 to swing with it between a forward position (shown in dashed lines in FIG. 4C) and a rearward position (shown in solid lines) along the double-arrow arc line B in FIG. 4C. While FIG. 4C shows a wide range of angular motion, preferably the pulley cassette is limited to swinging more than 30 degrees forward or rearward from the neutral position shown in FIGS. 4A and 4B.

Within the housing 74 are three axles on which pulleys 71, 72, and 73 are mounted for rolling movement. When the pulley cassette 70 is in the neutral position of Figures 4A and 4B, these pulleys 71, 72, and 73 are mounted in a vertically offset manner relative to the pulleys 64, 65, and 66. The tether 52 extends from the pulley 66 up the inside of the housing 25, over the first pulley 71, then under the second pulley 72, and then again over the third pulley 73. A hole 85 is formed through the outside 76 of the housing 74, and a strong bracket attached to the outside of the hole 85 has a corresponding hole. A stop 87 is secured to the tether 52 to prevent the tether 52 from being pulled further into the pulley cassette 70 than desired.

In operation, the user uses the device 10 to assist in locomotor movements. The device 10 is useful for physical therapy, rehabilitation, and athletic training. Returning to FIG. 1, a user 90 is shown using the device 10 within the user receiving area 36. The user is wearing a harness 91. The harness 91 includes an adjustable waist belt 92, an adjustable thigh strap 93, an adjustable lap strap 94, and an outer or lateral strap 95 on either side of the harness 91 that inelastically connects the waist belt 92, the thigh strap 93, and the lap strap 94. In FIG. 1, the tethers 52 from both the load-relieving assemblies 13 and 14 are shown attached directly to the waist belt 92. The tethers 52 are preferably attached to a point at the height of the area between the hip joint and the waist. In other embodiments, the tethers 52 may be terminated by a clip, such as a carabiner, for coupling to a loop on the waist belt 92. The tethers 52 are attached to either side of the waist belt 92 just above the hip joint. In this way, each tether 52 acts independently on each side of the body.

The harness 91 connects the user 90 to the device 10. When the user 90 walks, the user's hip joints move up and down. In normal walking motion, when the left leg moves forward, the left hip joint rises slightly, the right hip joint drops slightly, and the pelvis rotates slightly. When this is done, on the left side 20, the cassette pulley 70 swings slightly forward, the tether 52 retreats (until the stop 87 is limited by encountering the bracket 86), and the leaf spring 50 flexes slightly toward its unloaded position. The force exerted by the leaf spring 50 is in the forward direction, which helps move the device 10 slightly forward. At the same time, on the right side 21, the cassette pulley 70 swings slightly backward, and the tether 52 extends to accommodate the right hip joint drop and the pelvis rotation. This pulls the tether 52 through the pulley cassette 70 and through the pulleys 64, 65, and 66, thereby rotating the cam assembly 51 and deflecting the leaf spring 50 to a greater extent. The leaf springs 50 on the left side 20 and the right side 21 exert an independent bias on the tether 52 on each side, and accordingly the user 90 feels that his body weight is at least partially relieved on both the left and right sides of his body. Furthermore, because the relief assemblies 13 and 14 are each independently a constant force-displacement system, rather than a simple spring force or exponential force-displacement system, the user 90 experiences a constant or consistent relief regardless of the degree of displacement on either side. In other words, the relief force experienced is constant regardless of whether the user 90 raises the right hip joint or lowers the right hip joint to a smaller or larger extent. In further words, if the user lowers the right hip joint a significant distance, the user does not experience a proportionally larger relief. For example, the device 10 can be set to provide a constant 50 lbs of relief. If the user lowers the hip joint a small amount, the user will feel 50 lbs of relief, and if the user lowers the hip joint a large amount, the user will still feel the same 50 lbs of relief.

Furthermore, because the relief assemblies 13 and 14 are independent of each other, the two sides of the user's body can and do move independently. In more detail operation, when the hip joint of the user 90 moves a certain distance, the tether 52 also moves this distance and unwinds from the cam 60. The anchor cable 62 winds around the cam 61, shortening its effective length and deflecting the leaf spring 50. As the cam assembly 51 unwinds, the leaf spring 50 bends more. However, because the leaf spring 50 and the cam assembly 51 combine to form a constant force displacement, the patient feels a constant upward relief force on that side of the harness 91. The displacement of the tether 52, whether it is one inch or six inches, does not produce a proportional change in the upward force. Rather, the displacement does not produce any change in the relief force essentially. In this manner, the device 10 provides constant relief to each side of the user's body, independent of each other.

In other embodiments, a sensor 100 in proximity to one of the wheels 12 measures the rolling distance. A sensor 101 at the stop 87, or at the pulley cassette 70, or at a location along the tether 52 measures the acceleration, and therefore the force, and possibly also the tilt angle. Each of the sensors 100 and 101 may include electronic components such as a microprocessor, gyroscope, accelerometer, memory chips, PCBs, etc. The readings from these two sensors 100 and 101 are correlated for later analysis, and doctors and physical therapists can use this information to determine stride length, foot position and swing phase duration, speed, work energy, and other kinematic and kinetic parameters of the gait movement, which can be compared for each side of the body and over time to evaluate rehabilitation. Furthermore, in some embodiments, these sensors 100 and 101 are coupled by wired or wireless data communication to a display head unit, such as a smartphone or other electronic device, preferably attached to the upper tube 22, to display such information to the user 90. The user 90 can switch between this information and other information by pressing a physical button or touching the head unit's display.

In some cases, the wheels of the device 10 can be removed. This removes mobility of the device 10, but instead, it can be placed on or around a treadmill. The bottom 17 of the frame can be bolted or otherwise secured onto the treadmill using holes 31 and 33. Alternatively, a pad or cushion applied to the bottom 17 of the frame 11 can support the device 10 around the treadmill. The user can then walk or run on the treadmill while bearing their weight as described above.

Figure 5 illustrates an alternative embodiment of the relief assembly 13 of the device 10. The following description applies equally to the alternative embodiment of the relief assembly 14. In this embodiment, two leaf springs are used in combination. Although Figure 5 is stylized in the form of a free body diagram, the reader following the description herein will nevertheless readily recognize and understand Figure 5.

The leaf spring 50 is mounted as in FIG. 3A, with the fixed end 53 fixed to the main tube 24 and the free end 54 free. The cam assembly 51 is mounted to the free end 54 for rotation, the anchor cable 62 is fixed, but the tether 52 extends to the harness via around the pulley 65. However, in this embodiment, a second leaf spring 110 is used. The leaf spring 110 is also a sprung arm, preferably, but not necessarily, identical in structure, characteristics, and construction to the leaf spring 50, and also includes a fixed end 111 and a free end 112. The leaf spring 110 is mounted parallel to the leaf spring 50. As used herein, the term "parallel" is analogous to two elements in an electrical circuit and does not necessarily refer to a geometric relationship or alignment between the two leaf springs 50 and 110. Specifically, the leaf spring 50 and cam assembly 51 are in a first position and the second leaf spring 110 is carried in a second position, the first position and the second position being aligned with one another in a different, but vertically offset manner. In this embodiment, the leaf springs 50 and 110 span the same extent, but are not necessarily identical.

A second leaf spring 110 is stacked above the leaf spring 50. A stiff inelastic cable 113 ties or couples the free end 112 of the leaf spring 110 to the free end 54 of the leaf spring 50 so that movement of the free end 54 immediately and directly transfers movement to the free end 112. This coupled arrangement increases the spring force of the leaf spring 50. The tether 52 remains wrapped around the cam assembly 51 on the leaf spring 50. By stacking the leaf springs on the frame 11 in this manner, the device 10 can relieve more weight from the user during operation. In other embodiments, more than two leaf springs can be stacked, although this is unlikely to be necessary for all but the most demanding weight needs.

6 shows another alternative embodiment of the device 10. Whereas the relief assembly 14 of Figs. 3A and 3B is mounted in a horizontal configuration with the leaf spring 50 extending rearward in a general direction and its free end 54 behind its fixed end 53, in Fig. 6 here the relief assembly 14 is mounted in a vertical configuration. This relief assembly 14 is mounted to a vertical housing 25 rather than to the horizontal top of the main tube 24. The leaf spring 50 is still mounted to a block 55, but the block 55 is fixed vertically to the housing 25 such that the leaf spring 50 extends upward rather than rearward. The free end 54 of the leaf spring 50 is above the fixed end 53, and when the leaf spring 50 flexes, the free end 54 is displaced rearward toward the housing 25. The leaf spring 50 exerts a biasing force against its curvature toward the front 18 of the device 10. Thus, when the user is moving forward, this forward bias also assists in moving the device 10 forward. FIG. 6 shows the relief assembly 14 in a relief position in solid lines, with the relief assembly 14 moving along the double-arrow arc line C toward the housing to the loaded position, similar to the displacement to the loaded position shown for the horizontal configuration in FIG. 3B. Other vertical configurations, including configurations that are vertically or horizontally inverted relative to the configurations described above, are possible and may be suitable. However, in general, a vertical configuration is defined as one in which the spring (in this case, the spring arm 50) extends vertically. Pulleys 64, 65, and 66 are also moved to a vertical arrangement, but the anchor cable 62 is still secured to the tie-down 63 on the housing 25 via the pulley 64. The tether 52 still passes through the pulleys 65 and 66, but now also extends through an additional pulley 120 that redirects the tether 52 upward through the housing and into the pulley cassette 70.

Figure 7 shows yet another alternative embodiment of the relief assembly 13 of the device 10, somewhat similar to that shown in Figure 5. The following description applies equally to the alternative embodiment of the relief assembly 14. In this embodiment, two leaf springs are used in combination. Although Figure 7 is stylized in the form of a free body diagram, readers understanding the description herein will readily recognize and understand Figure 7.

The leaf spring 50 is mounted as in FIG. 3A, with the fixed end 53 fixed to the main tube 24 and the free end 54 free. The cam assembly 51 is mounted to the free end 54 for rotation, the anchor cable 62 is fixed, but the tether 52 extends to the harness via around the pulley 65. However, in this embodiment, a second leaf spring 130 is used. The leaf spring 130 is also a sprung arm, preferably, but not necessarily, identical in structure, characteristics, and construction to the leaf spring 50, and also includes a fixed end 131 and a free end 132. The leaf spring 130 is mounted parallel to the leaf spring 50, but below or on the opposite side of the main tube 24 from the leaf spring 50. As used herein, the term "parallel" is analogous to two elements in an electrical circuit and does not refer to a geometric relationship or alignment between the two leaf springs 50 and 130. Specifically, the leaf spring 50 and cam assembly 51 are in a first position and the second leaf spring 130 is carried in a second position, the first position and the second position being aligned with one another in a different, but vertically offset, manner. In this embodiment, the leaf springs 50 and 130 span the same extent, but are not necessarily identical.

The second leaf spring 130 is stacked below the leaf spring 50 and has an inverted position, so that the leaf spring 50 deflects downward under load, while the second leaf spring 130 deflects upward. An inelastic cable 133 connects the free end 132 of the leaf spring 130 to the inner cam 61 at the free end 54 of the leaf spring 50, so that rotation of the inner cam 61 directly imparts upward movement of the free end 132 of the leaf spring 130, as well as downward movement of the free end 54 of the leaf spring 50. The cable 133 passes through the bore 134 of the main tube 24. This connected arrangement increases the spring force of the relief assembly beyond that of the relief assembly 13 or 14. The tether 52 remains wrapped around the outer cam 60 of the cam assembly 51 on the leaf spring 50. By coupling the leaf springs onto the frame 11 in this manner, the device 10 is able to take more weight off the user during operation. In other embodiments, three or more leaf springs can be stacked on either side of the main tube 24 and coupled together, although this is unlikely to be necessary for all but the most demanding weight needs.

In some embodiments, the cam assembly 51 need not be attached directly to the leaf spring 50, or in other words, the cam assembly 51 can be separate from the spring. For example, the leaf spring 50 of FIG. 7 can be modified to be a rigid, inflexible, inflexible arm 50. In this embodiment, the cam assembly 51 is simply attached to an arm 50 similar to a rigid post above the main tube 24. The arm 50 is therefore considered simply a part of the frame 11, or a rigid extension thereof. The cam assembly 51 is thus coupled to the second or free end 132 of the bendable leaf spring 130 by an inelastic cable 133, and also to the harness by a tether 52. The leaf spring 130 is the only arm that moves in this arrangement, and as the harness descends, the tether 52 pulls and rotates the cam assembly 51, and the cable between the cam assembly 51 and the leaf spring 130 pulls and bends the leaf spring 130. This embodiment is an example in which the cam assembly and leaf spring are separate relief assemblies, illustrating that the cam assembly does not need to be carried or attached onto the leaf spring. In fact, the relief assembly still effectively operates as a constant force displacement system when the cable 133 (or anchor cable 62) connects the cam assembly to the spring (such as leaf spring 130) in one direction and the tether 52 connects the cam assembly to the harness in the opposite direction, regardless of whether the cam assembly is attached to or detached from the spring. This alternative version of FIG. 7 exemplarily illustrates such an arrangement. In other embodiments, the spring arm and cam assembly may be separate and not attached to each other, and the arrangement of the cam assembly and spring arm may actually be reversed, with the cam assembly 51 attached to the main tube 24, the spring arm 50 separate from the cam assembly 51 and attached to the main tube 24 and extending away, an anchor cable 62 coupled to a tie-down 63 extending to the cam assembly 51, and then a tether 52 extending from the cam assembly 51 over the free end 54 of the leaf spring 50 and then toward the harness (possibly through a pulley assembly).

Figures 8-10B show other alternative embodiments of an unloading assembly suitable for use with the device 10. The following description applies equally to an unloading assembly used on the left or right side 20 of the frame 21, or in an alternative location, to support a user within the device 10. Figure 8 shows a stylized free-body view of the unloading assembly 140, but still illustrates the structural elements and features of the assembly 140. The unloading assembly 140 is positioned within the frame 11 proximate to the main tube 24 and the vertical tube or housing 25.

The relief assembly 140 includes a leaf spring 141, a cam assembly 142, a first tether 143 extending from the leaf spring 141 to the cam assembly 142, and a second tether 144 extending from the cam assembly 142 and running up (or possibly through) the housing 25 to the pulley cassette 70 described above. As described above, the relief assembly 140 exerts a relief force of the harness 91 against the frame 11 and the load carried therein in response to the load applied to the harness 91.

The leaf spring 141 is a sprung arm, a lightweight, compact, elastic, elongated leaf spring member having a first fixed end 150 and a second free end 151. The fixed end 150 is fixed in a sleeve attached to a block 152. The adjustment knob 153 passes through a hole in the fixed end 150 and enters a threaded hole in the block 152. The adjustment knob 153 is thereby threadably engaged with the block 152 and can be tightened and loosened to change the spring force of the leaf spring 141. To decrease the spring force, the adjustment knob 153 is loosened and retracted from the bore to allow the fixed end 150 to rise slightly away from the block 152. To increase the spring force, the adjustment knob 153 is tightened into the bore to hold the fixed end 150 close to the block 152. The adjustment knob 153 is a means for adjusting the spring force of the leaf spring 141, and in other embodiments, the adjustment knob 153 can be an electrical, electromechanical, or electromagnetic adjustment device, or an adjustable bolt, or some other means for changing the spring force.

The leaf spring 141 acts as a spring. It is mounted in a horizontal configuration in which the free end 151 is at the same height as the fixed end 150 and moves between a first "unloaded" position, as shown in solid lines in FIG. 8, and a second "loaded" position, as shown in dashed lines in FIG. 8, in which the free end 151 is elevated above the fixed end 150 and away from the main tube 24. This movement is indicated by the arcuate double-arrow line 154.

The leaf spring 141 moves toward a loaded position in response to a load being applied to the harness 91, such as by the user 90 walking and pulling the leaf spring 141 upward via the second tether 144. Throughout this description, "load" is used to describe any weight or other downward force exerted on the harness 91 and should be understood as such. The load is preferably a live load, such as the user 90 in the harness, or the load may be any other weight or downward force acting on the unloading assembly 140. In response to the application of the load, the leaf spring 141 exerts a biasing force in a direction opposite to the pull of gravity, causing the user 90 to translate downward vertically during walking movements and stretching the second tether 144 due to lateral translation of the pelvis, and the leaf spring 141 acts to pull back on the second tether 144. Other horizontal configurations, including configurations that are vertically or horizontally inverted relative to the configurations described above, are also possible and may be suitable. However, in general, a horizontal configuration is defined as the spring (in this case, spring arm 141) extending horizontally.

In this manner, the leaf spring 141 is simply a spring that exerts a biasing force against displacement, whether through flexure, extension, or compression of the spring. And in this sense, other springs such as coil springs, air springs, torsion springs, etc. may be suitable. The leaf spring 141 has a non-constant force-displacement curve such that the force generated by the leaf spring 141 increases as the displacement of the three ends 151 increases, with greater displacement resulting in greater spring force. The leaf spring 141 is oriented horizontally toward the housing 25, with the free end 151 terminating below the cam assembly, such that flexure of the leaf spring 141 causes the spring 141 to bend toward the cam assembly 142 and to flex upward.

The cam assembly 142 is mounted for rotation on an axle 160 carried by a bracket 161. The bracket 161 is fixed to the housing 25 and extends forward. The cam assembly 142 includes an outer cam 162 and an inner cam 163. The stacked cam assembly 142 includes an outer cam 162 and an inner cam 163 mounted coaxially side-by-side on the bracket 161. Both cams 162 and 163 are mounted for rotation relative to one another about the same axis of rotation, but the cams 162 and 163 are fixed to one another to prevent relative rotation relative to one another.

Outer cam 162 is larger and inner cam 163 is smaller. In this drawing, both cams 162 and 163 are circular wheels. Although the cams are concentric with one another, the axle 160 to which they are attached is not concentric, and thus cams 162 and 163 are mounted for eccentric rotation. In other words, the axes of rotation of the cams are offset from their respective geometric centers such that as the cams rotate, their lever arms change and the ratio of their respective lever arms changes. In other embodiments, axle 160 is concentrically mounted to cams 162 and 163, and in other embodiments, cams 162 and 163 have shapes other than circles.

The first tether 143 is an inelastic cable, band, cord, or other tether. One end of the first tether 143 is coupled to the free end 151 of the leaf spring 141, and the other end of the first tether 143 is coupled to the inner cam 163. The inner cam 163 has at least a single groove formed around its periphery, and as the inner cam 163 rotates, the first tether 143 rolls and unwinds from the groove.

Similarly, the second tether 144 is an inelastic cable, band, cord, or other tether. One end of the second tether 144 is coupled to the outer cam 162. From there, the second tether 144 extends over the housing 25, then upward, to the pulley cassette 70, and then finally to the harness 91. The pulley cassette 90 and harness 91 are not shown in FIG. 8, but the reader will understand their location and arrangement from the above description. The outer cam 162 has at least a single groove formed about its periphery, and as the outer cam 162 rotates, the second tether 144 rolls and unwinds from this groove.

The first tether 143 and the second tether 144 are disposed opposite each other on the cam assembly 142. The first tether 143 is secured to an attachment point 164 on the inner cam 163 and extends downward to the leaf spring 141. The second tether 144 is secured to an attachment point 165 on the outer cam 162 and extends upward to the pulley cassette. The attachment points 164 and 165 are diametrically opposite each other. In other embodiments, the attachment points 164 and 165 can be in different locations, but the tethers extend outward in opposite directions. Because of this opposing arrangement, when a load is applied to the harness, the second tether unwinds from the outer cam 162, rotating the second 162 in a clockwise direction (as shown on the page) and the first tether rolls over the inner cam 163.

In FIG. 8, the second tether 144 extends generally upward as it is redirected by the pulley 166. A small pulley 166 attached to the bracket 161 for rotation near the top of the bracket 161 redirects the second tether 144 from its horizontal tangent exiting the outer cam 162 upward just along the outside of the housing 25 to the pulley cassette 70. In some embodiments, the pulley 166 directs the second tether 144 toward the interior of the housing 25.

With the first tether 143 wrapped around a groove formed in the inner cam 163 and the second tether 144 wrapped around a groove formed in the outer cam 162, the leaf spring 141 and cam assembly 142 together form a constant force displacement system. In other words, beyond a predetermined displacement, additional displacement does not significantly change the tension or force of the second tether 144 required for continued displacement. Additionally, other embodiments of the device 10 use different cam combinations, including assemblies with more than two cams, cams of different sizes and shapes than those presented herein, cams of similar sizes, etc.

Figure 9 shows a stylized free body view of the relief assembly 170, but still illustrates the structural elements and features of the assembly 170. The relief assembly 170 is positioned within the frame 11 between the front tube 26, the main tube 24, and the vertical tube or housing 25.

The load-relief assembly 170 includes a leaf spring 171, a cam assembly 172, a first tether 173 extending from the leaf spring 171 to the cam assembly 172, and a second tether 174 extending from the cam assembly 172 and running inside the housing 25 to the pulley cassette 70 described above. As described above, the load-relief assembly 170 exerts a load-relief force of the harness 91 against the frame 11 and the load carried within the harness.

Leaf spring 171 is a sprung arm, a lightweight, compact, resilient, elongated leaf spring member having a first fixed end 180 and a second free end 181. Fixed end 180 is fixed within a sleeve attached to block 182. Unlike relief assembly 140, no adjustment knob is used for leaf spring 171, although the reader will readily appreciate that an adjustment knob may be incorporated, but should nevertheless be considered part of the scope of this disclosure. Additionally, in other embodiments, the spring force of leaf spring 171 may be adjusted by an electrical, electromechanical, or electromagnetic adjustment device or an adjustable bolt, or some other means for changing the spring force.

The leaf spring 171 acts as a spring. The leaf spring 171 is mounted in a diagonal configuration. A block 182 to which a fixed end 180 is fixed is fixed near its top to the front tube 26. The leaf spring 171 then extends along the diagonal length of the front tube 26 toward the main tube 24. The free end 181 is below and forward of the fixed end 180 and moves between a first "unloaded" position as shown in solid lines in FIG. 9 and a second "loaded" position as shown in dashed lines in FIG. 9 in which the free end 181 is pulled back away from the front tube 26 toward the housing 25. This movement is indicated by the arcuate double-arrow line 183.

As with other unloading assemblies, the leaf spring 171 moves toward a loaded position as the harness 91 is loaded, such as by the user 90 walking and pulling the leaf spring 171 downward via the second tether 174. In response, the leaf spring 171 exerts a biasing force in a direction opposite to the pull of gravity, causing the user 90 to translate vertically downward during walking movements, and the leaf spring 171 acts to pull back on the second tether 174 as the lateral translation of the pelvis stretches the second tether 174. Other configurations are possible and may be suitable, including configurations that are vertically or horizontally inverted relative to the configurations described above. However, a diagonal configuration is generally defined as one in which the spring (in this case, the spring arm 171) extends diagonally, particularly but not necessarily, along the front tube 26.

The leaf spring 171 is a spring that exerts a biasing force against a displacement, whether through flexure, extension, or compression. In this sense, other springs such as coil springs, air springs, torsion springs, etc. may be suitable. The leaf spring 171 has a non-constant force-displacement curve such that the force generated by the leaf spring 171 increases as the displacement of the free end 181 increases, with greater displacement resulting in greater spring force.

The cam assembly 172 is mounted for rotation on an axle 190 carried by a bracket 191. The bracket 191 is fixed to the housing 25 and extends forward. The cam assembly 172 includes an outer cam 192 and an inner cam 193. The stacked cam assembly 172 includes an outer cam 192 and an inner cam 193 mounted coaxially side-by-side on the bracket 191. Both cams 192 and 193 are mounted for rotation relative to one another about the same axis of rotation, but the cams 192 and 193 are fixed to one another to prevent relative rotation relative to one another.

Outer cam 192 is larger and inner cam 193 is smaller. In this embodiment, both cams 192 and 193 are circular wheels. Although the cams are concentric with one another, the axle 190 to which they are attached is not concentric, and therefore cams 192 and 193 are eccentrically mounted for rotation. In other words, the axes of rotation of the cams are offset from their respective geometric centers such that as the cams rotate, their lever arms change and the ratio of their respective lever arms changes. In other embodiments, the axle 190 is concentrically mounted to cams 192 and 193, and in other embodiments, cams 192 and 193 have shapes other than circles.

The first tether 173 is an inelastic cable, band, cord, or other tether. One end of the first tether 173 is coupled to the free end 181 of the leaf spring 171, and the other end of the first tether 173 is coupled to the inner cam 193. The inner cam 193 has at least a single groove formed around its periphery, and as the inner cam 193 rotates, the first tether 173 rolls and unwinds from the groove.

Similarly, the second tether 174 is an inelastic cable, band, cord, or other tether. One end of the second tether 174 is coupled to the outer cam 192. From there, the second tether 174 extends upward through the housing 25 and to the pulley cassette 70 and then finally to the harness 91. The pulley cassette 90 and harness 91 are not shown in FIG. 9, but the reader will understand their location and arrangement from the above description. The outer cam 192 has at least a single groove formed about its periphery, and as the outer cam 192 rotates, the second tether 174 rolls and unwinds from this groove.

The first tether 173 and the second tether 174 are disposed opposite one another on the cam assembly 172. The first tether 173 is secured to an attachment point 194 on the inner cam 193 and extends downward to the leaf spring 171. The second tether 174 is secured at an attachment point 195 on the outer cam 194 and then extends generally upward to the pulley cassette. The attachment points 194 and 195 are diametrically opposite one another on the cam assembly 172. In other embodiments, the attachment points 194 and 195 can be in different locations, but the tethers extend outward in opposite directions.

Two pulleys 196 and 197 redirect the first tether 173 and the second tether 174. The first pulley 196 is attached to the main tube 24 for rotation and redirects the first tether 173. The first tether 173 extends diagonally downward from the free end 181, wraps around under the first pulley 196, and then extends diagonally upward to the attachment point 194 of the inner cam 193. The second pulley 197 is attached to the bracket 191 near the top of the bracket 191 for rotation. A small cut is made in the housing 25 to allow the pulley 197 to be partially positioned within the housing 25. The pulley 197 redirects the second tether 174 from its horizontal tangent exiting the outer cam 192 upward just inside the housing 25 to the pulley cassette 70. In some embodiments, the pulley 197 directs the second tether 174 along the exterior 25 of the housing.

With the first tether 173 wrapped around a groove formed in the inner cam 193 and the second tether 174 wrapped around a groove formed in the outer cam 192, the leaf spring 171 and cam assembly 172 together form a constant force displacement system. In other words, beyond a predetermined displacement, additional displacement does not significantly change the tension or force of the second tether 174 required for continued displacement. Additionally, other embodiments of the device 10 use different cam combinations, including assemblies with more than two cams, cams of different sizes and shapes than those presented herein, cams of similar sizes, etc.

10A and 10B show the unloaded and loaded positions of another embodiment of the unloading assembly 210. The drawings show a stylized free body view, but still show the structural elements and features of the assembly 210. The unloading assembly 210 is positioned within the frame 11 between the front tube 26 (here shown vertically), the main tube 24, and the vertical tube or housing 25.

The load-relief assembly 210 includes a spring 211, a cam assembly 212, a first tether 213 extending from the spring 211 to the cam assembly 212, and a second tether 214 extending from the cam assembly 212 and running inside the housing 25 to the pulley cassette 70 described above. The load-relief assembly 210 exerts a load-relief force of the harness 91 against the frame 11 and the load carried therein.

The spring 211 is a tension coil spring. The spring 211 has a first fixed end 220 and a second free end 221. The fixed end 220 is coupled to a bolt 222, such as an eyebolt, that is threaded or otherwise secured to the front tube 26. The spring 211 is mounted in a horizontal configuration and oriented along the horizontal length of the main tube 24. The free end 221 of the spring 211 is disposed in the housing 24. FIG. 10A shows a first "unloaded" position and FIG. 10B shows a second "loaded" position. In the unloaded position, the spring 211 is compressed and has a shorter length. In the loaded position, the spring 211 is extended and has a longer length. The spring 211 stretches along the length of the main tube 24 when loaded.

As with other unloading assemblies, the spring 211 moves toward a loaded position as the harness 91 is loaded, such as by the user 90 walking and stretching the spring 211 via the second tether 214. In response, the spring 211 exerts a biasing force in a direction opposite to the pull of gravity, vertically translating the user 90 downward during walking movements, and the lateral translation of the pelvis stretches the second tether 214, and the spring 211 acts to pull back the second tether 214. Other configurations with the spring 211 are possible and may be suitable, including configurations that are vertically or horizontally inverted relative to the configurations described above. However, a horizontal configuration is generally defined as the spring 211 extending horizontally, particularly, but not necessarily, along the main tube 24.

The cam assembly 212 is mounted for rotation on an axle 230 carried by a bracket 231. The bracket 231 is fixed to the housing 25 and extends forward. The cam assembly 212 includes an outer cam 232 and an inner cam 233. The stacked cam assembly 212 includes an outer cam 232 and an inner cam 233 mounted coaxially side-by-side on the bracket 231. Both cams 232 and 233 are mounted for rotation relative to one another about the same axis of rotation, but the cams 232 and 233 are fixed to one another to prevent relative rotation relative to one another.

Outer cam 232 is larger and inner cam 233 is smaller. In this embodiment, both cams 232 and 233 are circular wheels. Although the cams are concentric with each other, the axle 230 to which they are attached is not concentric, and therefore cams 232 and 233 are eccentrically mounted. In other words, the axes of rotation of the cams are offset from their respective geometric centers such that as the cams rotate, their lever arms change and the ratio of their respective lever arms changes. In other embodiments, axle 230 is concentrically mounted to cams 232 and 233, and in other embodiments, cams 232 and 233 have shapes other than circles.

The first tether 213 is an inelastic cable, band, cord, or other tether. One end of the first tether 213 is coupled to the free end 221 of the spring 211, and the other end of the first tether 213 is coupled to the inner cam 233. The inner cam 233 has at least a single groove formed around its periphery, and as the inner cam 233 rotates, the first tether 213 rolls and unwinds from the groove.

Similarly, the second tether 214 is an inelastic cable, band, cord, or other tether. One end of the second tether 214 is coupled to the outer cam 232. From there, the second tether 214 extends upward through the housing 25 and to the pulley cassette 70, and then finally to the harness 91. The pulley cassette 90 and harness 91 are not shown in Figures 10A and 10B, but the reader will understand their location and arrangement from the above description. The outer cam 232 has at least a single groove formed about its periphery, and as the outer cam 232 rotates, the second tether 214 rolls and unwinds from this groove.

The first tether 213 and the second tether 214 are disposed opposite one another on the cam assembly 212. The first tether 213 is secured to an attachment point 234 on the inner cam 233 and extends generally downward to the spring 211. The second tether 214 is secured to an attachment point 235 on the outer cam 234 and then extends generally upward to the pulley cassette. The attachment points 234 and 235 are diametrically opposite one another on the cam assembly 212. In other embodiments, the attachment points 234 and 235 can be in different locations, but the tethers extend outward in opposite directions.

Two pulleys 236 and 237 redirect the first tether 213 and the second tether 214. The first pulley 236 is attached to the main tube 24 for rotation and redirects the first tether 213. The first tether 213 extends horizontally from the free end 221 of the spring 211, wraps around the first pulley 236, and then extends vertically upward to the attachment point 234 of the inner cam 233. The second pulley 237 is attached to the bracket 231 for rotation near the top of the bracket 231 and slightly within the housing 25. The second pulley 237 redirects the second tether 214 from its horizontal tangent exiting the outer cam 232 upward just inside the housing 25 to the pulley cassette 70. In some embodiments, the pulley 237 directs the second tether 214 along the outside 25 of the housing.

With the first tether 213 wrapped around a groove formed in the inner cam 233 and the second tether 214 wrapped around a groove formed in the outer cam 232, the spring 211 and cam assembly 212 together form a constant force displacement system. In other words, beyond a predetermined displacement, additional displacement does not significantly change the tension or force of the second tether 214 required for continued displacement. Additionally, other embodiments of the device 10 use different cam combinations, including assemblies with more than two cams, cams of different sizes and shapes than those presented herein, cams of similar sizes, etc.

11A-11C show a harness 240 and its components. Preferably, the harness 240 is used in place of the harness 91 described above. The harness 240 includes an adjustable waist belt 241, adjustable thigh straps 242, a cross piece 243 connecting the thigh straps 242, and an outer or lateral strap 244 on each side of the harness 240 that inelastically connects the waist belt 241 to each of the thigh straps 242.

The waist belt 241 is a length of webbing or other suitable strong and durable material that is looped at the front of the harness 240 by a buckle 245. Similarly, the thigh straps 242 are lengths of webbing or other suitable strong and durable material that are looped at the front of the harness 240 by a buckle 246. The length of the webbing can be pulled through the buckles 245 and 246 to adjust the waist belt 241 and the thigh straps 242, respectively, to fit the user snugly.

The lateral straps 244 connect the thigh strap 242 to the waist belt 241. Since the lateral straps 244 are the same, only one will be described herein with the understanding that the description applies equally to both. The lateral straps 244 shown in both FIG. 11A and FIG. 11B include an inner strap 250 and an outer strap 251. The inner strap 250 is a length of webbing or other suitable strong and durable material and is sewn directly to the waist belt 241 and the thigh strap 242. The outer strap 251 is also a length of webbing or other suitable strong and durable material. The outer strap 251 is sewn to the inner strap 250 along approximately the top half of the inner strap 250. The outer strap 251 then separates from the inner strap 250. The ring strap 252 is disposed between the inner strap 250 and the outer strap 251 along the lower half of them.

11C. The ring strap 252 is a length of webbing or other suitable strong and durable material that is folded over on itself to define an inner portion 254, an outer portion 255, and an upper curved portion 256 between the inner portion 254 and the outer portion 255. During manufacture of the harness 240, the ring 253 fits between the inner portion 254 and the outer portion 255 and is positioned within and against the curved portion 256. The inner portion 254 and the outer portion 255 are then sewn together to close the ring strap 252 and secure the ring 253 therein. The outer strap 251 is further sewn onto the outer portion 255 of the ring strap 252, and possibly also to the inner portion 254 and/or the inner strap 250, to secure the lateral straps 244.

The ring 253 is secured to the lateral strap 244 to hold one of the tethers. In FIG. 11C, a tether identified by reference number 144 is used, which corresponds to the relief assembly 140 of FIG. 8, but the reader should understand that the second tether 144 can be one of the various other tethers (or the first or second tether) described herein that lead from the relief assembly. The second tether 144 terminates in a disk-shaped puck 260, shown in dashed lines in FIG. 11C. The puck 260 is rigid, durable, and permanently secured to the end of the second tether 144. The puck 260 slides over and secures the ring 253 to couple and engage the harness 240 to the relief assembly 140.

The ring 253 includes a backer plate 261, a front plate 262, and a side wall 263 formed therebetween. The backer plate 261 is flat and triangular in shape and has a bottom 264 with a longitudinal slot 265 formed therethrough. The slot 265 is shown in dashed lines in FIG. 11C. The front plate 262 is flat and generally triangular in shape. The front plate 262 has a bottom 270 with a longitudinal slot 271 formed therethrough. The slots 265 and 271 are coextensively aligned with one another. The curved portion 256 of the ring strap 252 passes through both the slots 265 and 271 to secure the ring 253 to the transverse straps 244.

The front plate 262 also has an open top 272. A slit 273 is formed centrally through the front plate 262 between the open top 272 and a circular hole 274. The top 272, slit 273, and hole 274 cooperate to define a passage for the end of the second tether 144. The second tether 144 and the puck 260 are applied through the passage and then moved upwardly, thereby being captured within the ring 253. The sidewall 263 prevents the puck 260 from coming loose from the ring 253. The sidewall 263 extends between the back plate 261 and the front plate 262 and includes an opening 280 that is aligned with and below the open top 272 of the front plate 262. From the opening 280, the sidewall 263 is aligned along the exterior of the ring 253, directly above the slots 265 and 271. The sidewall has a large internal cavity 281, shown in dashed lines in FIG. 11C. The internal cavity 281 is preferably, but not necessarily, circular. The internal cavity 281 is offset from the circular hole 274 and proximate the top of the ring 253. In this manner, the puck 260 moves into the internal cavity 281 when applied through the circular hole 274. When the user dons the harness 240 and applies a load to the unloading assembly 140, the puck 260 slides up within the internal cavity 281 toward the top of the ring 253 into a captured position where it cannot inadvertently come loose. The puck 260 cannot be pulled out of the ring 253 without unloading the tether 144 and pulling the puck 260 down and out of the circular hole 274.

Embodiments of relief assemblies 140, 170, and 210 are used in device 10 in the same manner as relief assemblies 13 and 14. Harness 240 is used in device 10 in the same manner as harness 91. Based on the above description, the reader will understand the operation of the device with any of relief assemblies 140, 170, or 210 substituted, or with harness 240 substituted.

The preferred embodiments have been described above fully and clearly to enable those skilled in the art to understand, make and use the same. Those skilled in the art will recognize that modifications can be made to the above description without departing from the spirit of the specification, and that some embodiments include only or a subset of the elements and features described. To the extent that modifications do not depart from the spirit of the specification, they are intended to be included within its scope.

Claims (21)

A body weight support walking exercise device,
a frame configured to support locomotion movement;
a load relief assembly carried by the frame,
a spring having a fixed end coupled to the frame and an opposing free end;
a cam assembly mounted on said frame for rotational movement;
a first tether extending from the free end of the spring to the cam assembly;
a second tether extending from the cam assembly to a load;
The weight-bearing locomotion apparatus, wherein the relief assembly exerts a relief force on the load against the frame. The apparatus of claim 1, wherein the cam assembly comprises a first cam and a second cam, each mounted for rotational movement. The device of claim 2, wherein the first tether is coupled to the first cam and the second tether is coupled to the second cam. The device of claim 2, wherein the first cam and the second cam are concentric with each other. The apparatus of claim 2, wherein the first cam and the second cam are mounted for eccentric rotational movement. The device of claim 1, further comprising a pulley, the second tether being routed around the pulley between the cam assembly and the load. The device of claim 1, wherein the spring is one of a leaf spring and a tension spring. A body weight support walking exercise device, comprising:
a frame configured to support locomotion movement; and a harness configured to receive a load against the frame;
a load relief assembly carried by the frame,
A spring,
a cam assembly mounted on said frame for rotational movement;
a first tether extending from the spring to the cam assembly;
a second tether extending from the cam assembly to the harness;
The weight-relief locomotion apparatus, wherein the relief assembly exerts a relief force in response to the load on the harness. The apparatus of claim 8, wherein the cam assembly comprises a first cam and a second cam, each mounted for rotational movement. The device of claim 9, wherein the first tether is coupled to the first cam and the second tether is coupled to the second cam. The device of claim 9, wherein the first cam and the second cam are concentric with each other. The apparatus of claim 9, wherein the first cam and the second cam are mounted for eccentric rotational movement. The device of claim 8, further comprising a pulley, the second tether being routed around the pulley between the cam assembly and the harness. The device of claim 8, wherein the spring is one of a leaf spring and a tension spring. A body weight support walking exercise device, comprising:
a frame configured to support locomotion movement; and a harness configured to receive a load against the frame;
a load relief assembly carried by the frame,
a spring having a fixed end coupled to the frame and an opposing free end;
a cam assembly mounted to the frame including first and second concentric cams each mounted for rotational movement;
a first tether extending from the free end of the spring to the first cam;
a second tether extending from the second cam to the harness;
The relief assembly exerts a relief force on the harness against the frame. 16. The device of claim 15, wherein the first tether is coupled to the first cam and the second tether is coupled to the second cam. The apparatus of claim 15, wherein the first cam and the second cam are mounted for eccentric rotational movement. The device of claim 15, wherein the first cam and the second cam are different sizes. The apparatus of claim 15, further comprising a pulley, the second tether being routed around the pulley between the cam assembly and the load. 20. The device of claim 19, further comprising another pulley, the first tether being routed around the other pulley between the spring and the cam assembly. The apparatus of claim 15 , wherein the spring is one of a leaf spring and a tension spring.

Images