DE29824629U1 - Height-adjustable bed, especially hospital or nursing bed - Google Patents

Description

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Hi-bu 011994de August 23, 2001

Height-adjustable bed, especially hospital or nursing bed

The invention relates to a height-adjustable bed, which can be used in particular as a hospital or nursing bed.

In the case of hospital or nursing beds, it is advantageous if the height of the bed can be adjusted in order to care for the patient or person in need of care (for the sake of simplicity, we will just refer to the patient from now on). It is also required that the bed can be moved easily, so its support legs should be fitted with castors or swivel castors. However, when caring for the patient, the bed should no longer be able to be moved accidentally, which is why the bed should have an appropriate braking device. In order to make the bed user-friendly and comfortable to use, it is advantageous if the braking device is automatically activated as soon as the bed is raised.

DE 41 17 277 Cl, DE 92 10 204 Ul and EP 0 433 737 B2 disclose height-adjustable hospital or nursing beds which are provided with castors, whereby the bed is fixed on the floor as soon as it is raised. A similar bed is also known from DE 44 05 509 C2. If a bed of this known type is in the raised position 0 and is to be moved, it is necessary to lower the bed first, since only in the lowered position is the braking device in its release position in which the bed can be moved. After the bed has been moved, it is raised again in order to continue caring for the patient.

From CH-PS 167 118 a height-adjustable bed is known in which four guide elements are arranged on a bed frame, from which

Support legs can be pushed out downwards or moved in from below. On the outside of the guide elements there are side brackets for castors that can be rotated around the guide elements. Using a lifting device, the support legs can be moved over the lower ends of the guide elements that face the floor. When lowered, the bed rests on the floor via its castors. As soon as the support legs have touched the floor, the guide elements lift off the floor. When raised, the castors are at a considerable height above the floor, as the distance of the castors from the bed frame remains unchanged. "Lifting" the castors impairs the overall aesthetic impression of the bed.

In the state of the art, there are beds whose braking mechanisms can be released even when raised so that the bed can be moved (see, for example, DE 295 05 180 Ul), but these beds require additional actuating units for the braking device, which increases the design effort and reduces user-friendliness.

The invention is based on the object of creating a height-adjustable bed in which the braking mechanism can be released in a structurally simple and user-friendly manner even when the bed is raised.

To solve this problem, the invention proposes a height-adjustable bed 5, which can be used in particular as a hospital or nursing bed and is provided with

a bed frame which has a frame with guide elements attached to it, in which support legs with rollers are slidably guided for moving the bed frame,

0 - a lifting device for moving the support legs and the guide elements relative to each other between a minimum extension position and a maximum extension position,

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wherein at least one of the support legs is associated with a braking device which can be moved into a locking position in which the bed frame cannot be moved and into a release position in which the bed frame can be moved,

- wherein the braking device can be moved into the locking position and into the release position under the control of the lifting device, in such a way that when the support leg is in the minimum extension position and the lifting device is activated, the latter first moves the braking device from the release position to the locking position and then extends the support leg, that the braking device remains in the locking position during the extension movement of the support leg until it reaches its maximum extension position or an intermediate position before the maximum extension position of the support leg, and that the lifting device moves the braking device from the locking position to the release position when activated after the maximum extension position or the intermediate position of the support legs has been reached.

The bed according to the invention is provided with a bed frame which has a frame with guide elements attached to it, on which 0 support legs are guided in a linearly displaceable manner, which have rollers at their downward-facing ends. The support legs can be locked in their respective displacement position relative to the guide elements. All support legs can be moved along the guide elements via a lifting device, namely between a minimum extension position in which the bed 5 assumes its lowest height position, and a maximum extension position in which the bed is raised the furthest upwards. At least one support leg and preferably each support leg is assigned a braking device which can be transferred into a locking position and a release position. In the locking position, the bed cannot be moved, while it can be moved in the 0 release position of the braking device. The braking device acts either on the rollers and blocks them directly or indirectly on the outer or inner radius, namely in a force-fitting manner (i.e. positively).

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and/or frictionally) in the fixed position, or it acts on the surface on which the bed rests (floor brake).

According to the invention, the braking device is controlled by the lifting device for transferring both from the release position to the locking position and vice versa, both in the minimum extension position of the support legs and in their maximum extension position or an intermediate position between these positions shortly before the maximum extension position. This means that in both extreme height adjustment positions (lowest and highest), the braking device can be released and locked when the lifting device is operated. The braking device is controlled by the lifting device in such a way that when the support legs are in the minimum extension position, the lifting device first transfers the braking device from the release position to the locking position and then extends the support legs. The braking device remains in its locking position throughout the entire extension movement. The nursing staff can now move the bed to the height suitable for caring for the patient. When the bed is raised, the braking effect of the braking device is canceled by the fact that the lifting device is activated even after the 0 maximum extension position has been reached, thereby moving the braking device from its locking position to the release position.

In the bed according to the invention, the height adjustment of the bed and the braking device are controlled by one and the same mechanism, namely the lifting device. Additional actuating elements with corresponding additional drives for this are therefore not provided for in the bed according to the invention. In addition, the operation of the bed according to the invention is extremely simple, since the activation or deactivation of the braking device can ultimately be carried out by the same 0 switch or by two different switches, which is/are also actuated to activate the lifting device.

In an advantageous development of the invention, the lifting device is automatically deactivated when the bed is raised when the support legs reach their maximum extension positions. If the nursing staff therefore want to move the bed to the highest position, in which the bed should of course be braked, this is achieved by automatically switching off the lifting device according to this development of the invention.

In order to activate the lifting device when the legs are in their maximum extended positions to release the braking device, according to an advantageous development of the invention, a switch is again actuated, which is preferably the same switch with which the lifting device was also activated to extend the support legs.

In an advantageous development of the invention, it is provided that the actuation of the lifting device in order to move the braking device from the release position to the locking position when the bed is lowered to the maximum is also carried out via the switch with which the extension movement of the support legs is triggered. Alternatively, another switch can be provided for this purpose. It is also expedient here if the lifting device is only activated until the 0 braking device has been moved from the release position to the locking position (when in its

Here too, it is advisable to force the lifting device to shut down, which then has to be reactivated for the actual extension movement of the support legs.
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Similar considerations and forced shutdown of the lifting device as explained above when raising the bed also apply when lowering the bed. In this case, it is advisable if the bed 0, which is in its uppermost position and not secured by the braking device, is first secured when the lifting device is activated, i.e. the lifting device is only activated until the braking device has been moved from its release position to the locking position. This then leads to a

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Forced shutdown of the lifting device, which is reactivated when a switch is operated again, which is in particular the switch that was previously operated to move the braking device from the release position to the locking position. The next forced shutdown of the lifting device occurs at the moment the support legs reach their minimum extended position. In this state, the braking device is still in its locking position, so that only when a switch is operated again, in particular the same switch, does the lifting device ensure that the braking device is moved from the locking position to the release position.

In the manner described above, the bed according to the invention is safe and convenient to operate for both the patient and the nursing staff.

With regard to a simple construction of the bed according to the invention, it is advantageous if the lifting device acts on the braking element via a pressure element, as a result of which the braking element moves against a stop on the support leg in order to take the support leg with it and extend it as the lifting device continues to act on the braking element. When the braking element is supported on the stop, the braking device assumes its locking position in which the braking element acts either on the castor or directly on the floor.

5 In an advantageous development of the invention, the guide element has a driver which, when the support leg is in the maximum extension position, engages a stop on the braking element. The support leg with the braking element located therein moves relative to the guide element into the maximum extension position. In this 0 position, the braking element strikes the driver with a stop.

If the support leg is now moved beyond this extended position, the driver holds back the braking element, which then moves relative to the support leg in

This is moved in and the braking device is moved from the locking position to the release position. When the bed is raised to the maximum, the braking device is moved from its locking position to the release position by moving the support leg a little beyond the maximum extension position or by moving the guide element relative to the support leg. This small amount of relative movement is sufficient to move the braking element so that the braking device is moved from its locking position to the release position.

In an expedient development of the invention, it is provided that the braking element is designed as a tappet, on one end of which the lifting device acts with its pressing element or the like and at the other end of which a brake block is arranged.

In a further advantageous embodiment of the invention, the lifting device has for each pair consisting of a guide element and a support leg an automatically pivotable, i.e. motor-driven, hydraulic or similar pivoting lever, one end of which is rotatably mounted on the frame and/or on a guide element of the bed frame and the other end of which acts on the associated support leg in order to move it along the

guide element. For each support leg that is equipped with a braking device, the pivot lever does not act directly on the support leg but indirectly via the braking element, which itself rests on the support leg.
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The guide elements and support legs are conveniently arranged in pairs at the foot and head ends of the bed frame, with two pivot levers arranged at each end of the bed frame. The pivot levers are alternately mounted on opposite guide elements so that they can rotate 0, while the free acting ends act on the support legs of the other guide ends. The force for pivoting the

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The pivot lever is preferably mounted in the (geometric) center of the pivot lever.

The pivoting levers run and move in planes parallel to each other.

The pivot levers, each of which rests with their ends on a guide element and a support leg of the two legs at the head end and foot end, rotate around their centers in opposite directions when the height of the bed is changed. In addition, there is a superposition of a linear movement of the joint connection points of the pivot levers with the guide elements.

Each pivot lever is preferably made of a flat material (steel plate), with a wider middle section between the two ends than at the ends towards which the pivot lever tapers. In particular, the pivot lever has a diamond-like shape. Such flat pivot levers can be accommodated in the head and foot ends of the bed frame, which protrude above the mattress, in a space-saving manner.

0 The pivoting movement of a pair of pivot levers arranged in a foot end or head end is expediently carried out by a spindle drive which meshes with a connecting element which is articulated and movably connected to the middle sections of the pivot levers, preferably via link levers, one end of which is pivotally connected to the pivot levers and the other end of which is pivotally connected to the connecting element. The spindle of the spindle drive extends parallel to the guide elements or support legs and is pivotally mounted on the bed frame so as to be secured against axial displacement. When the spindle rotates, the pivot levers rotate about their pivot points with the bed frame or the guide elements and their 0 support points on the support legs or the at least one braking element assigned to one of the support elements.

In an advantageous development of the invention, it is provided that the pivot lever which is assigned to the support leg provided with the braking device is coupled at its acting end in a displaceable and articulated manner to the plunger of the braking device. This plunger is expediently mounted in the support leg so that it can be displaced between a disengagement position and a retraction position, whereby it runs parallel to the extension of the support leg. The above-mentioned articulated and displaceable connection of the acting end of the pivot lever to the plunger is expedient in order to convert the pivoting movement of the pivot lever into a linear movement of the support leg while maintaining its coupling with the plunger of the braking device.

In an advantageous development of the invention, it is further provided that the plunger has an elongated hole extending in its direction of movement, in which one end of a connecting lever is guided, the other end of which is connected in an articulated manner to the acting end of the pivot lever. Alternatively, it can be provided that the acting end of the pivot lever is provided with an elongated hole running essentially transversely to the pivoting direction of the pivot lever, in which the plunger is guided. Both alternatives are expedient in that the pivoting movement of the pivot lever can be converted into a linear movement of the support leg while maintaining the coupling with and the pressure against the plunger.

5 The above considerations regarding the activation and deactivation of the braking device in the maximum extension position of the support legs also apply accordingly if the control system is designed in such a way that the braking device can be moved by the lifting device from the locking position to the release position and vice versa when the support legs are in the intermediate position close to the maximum extension position.

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According to an alternative variant of the bed according to the invention, it is provided with

a bed frame which has a frame with guide elements attached to it, in which support legs with rollers are slidably guided for moving the bed frame,

a lifting device for moving the support legs and the guide elements relative to each other between a minimum extension position and a maximum extension position,
wherein at least one of the support legs is associated with a braking device which can be moved into a locking position in which the bed frame cannot be moved and into a release position in which the bed frame can be moved,

wherein the braking device has a braking element which can be moved by the lifting device when the support leg is in the minimum extension position in order to transfer the braking device from the release position to the locking position, wherein the braking element rests against the support leg and/or a stop of the support leg when the braking device is in the locking position and a pressing element of the lifting device which is supported by a

0 Drive device of the lifting device can be driven against the

Brake element presses and moves the support leg and the guide element relative to each other.

In this variant, the braking element is moved against the support leg and brought into contact with it via a pressing element, which is driven by the lifting device that is supported against the bed frame. The pressing element then moves the support leg and its guide element apart from one another via the braking element. As a result, when the bed frame is lowered, the braking device is moved from the release position to the locking position by the lifting device, before there is a relative movement between the support leg and the guide element. The roller of the support leg remains in the area close to the ground, i.e.

directly above the floor on which the bed rests. The relative position of the castor to the ground when the brake is in the locking position therefore remains the same when the height of the bed frame is changed.

This type of braking device can also be used in the (first) variant of the invention described above. Conversely, the variants of the invention and their further developments can also be used in the (second) variant of the invention described in the previous paragraph.

Using the lifting mechanism described above, a bed, in particular a hospital or nursing bed, can also be constructed that is height-adjustable in a simple manner without one or more braking devices being activated or deactivated when adjusting the height. The bed according to this third variant of the invention is provided with

- a bed frame having a frame with guide elements attached to it, in which support legs with rollers are slidably guided for moving the bed frame, and
a lifting device for moving the support legs and the guide elements relative to each other between a minimum 0 extension position and a maximum extension position,

wherein the lifting device has an automatically pivotable pivot lever for each pair consisting of a guide element and a support leg, one end of which is rotatably mounted on the frame and/or a guide element of the bed frame

5 and the other end of which acts on a support leg.

In the lifting mechanism described here, the support legs of two adjacent legs of the bed are alternately connected via two pivot levers. Each pivot lever is supported on the guide element of one leg 0 or the frame of the bed frame and on the support leg of the other leg of the bed frame. By simultaneously pivoting these two pivot levers in opposite directions, in particular in the middle area of both

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If a (connecting) element that can be moved parallel to the alignment of the legs is arranged on the pivot lever and is coupled to the pivot levers, the support legs and the guide elements are moved relative to one another, away from one another when the bed is raised and towards one another when the bed is lowered.

The lifting device described here and the height-adjustable bed can be advantageously combined with the various further developments of the braking device described above.

An embodiment of the invention is explained in more detail below with reference to the figures. In detail:

Fig. 1 is a side view of an embodiment of the bed according to the invention,

Fig. 2 is a section along the line H-II of Fig. 1 to illustrate the lifting mechanism for raising the bed and for operating the braking device,

Fig. 3 is a sectional view similar to that of Fig. 2 with the bed in its maximum raised position,

Fig. 4 is a vertical section through a leg of the bed with a braking device therein, with the movable support leg in its minimum extended position and the braking device in its locking position,

Fig. 5 a section similar to that of Fig. 4 with the supporting leg already partially extended,

Fig. 6 is a view similar to that of Figs. 4 and 5, with the support leg in its maximum extended position and the braking device still in its locking position,

Fig. 7 is a sectional view of the support leg in its maximum extended position and with the braking device in the release position,

Fig. 8 an alternative embodiment for the mechanical coupling of the acting end of a swivel arm with the braking element of the braking device and

Figs. 9 and 10

Sectional and side views of an alternative braking device which acts on the rollers instead of the floor to block them.

Fig. 1 shows a side view of a bed 10 which is provided with a lifting mechanism for raising and lowering the bed, whereby the lifting mechanism 0 also actuates the braking device, by means of which the bed can optionally be secured against movement. The bed 10 has a bed frame 12 which has a frame 14 supporting the lying surface with parallel longitudinal beams 16 and transverse beams 18 running transversely to these (see Figs. 2 and 3). In the corner areas of the frame 14 there are four guide elements 20-24 which are connected to the frame 14 and run perpendicular to the longitudinal and transverse beams 16, 18. The guide elements 20-24 are designed as hollow profile square tubes which are open at the bottom or as telescopic tubes of a different shape. In Fig. 1, one guide element 20,22 of the two guide elements located at the head end 26 and foot end 28 of the bed frame 12 is shown, while Fig. 2 shows the two guide elements 22,24 of the bed frame foot end 28. In each guide element 20-24 there is a support leg 30-34, whereby here too

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Fig. 1 only one support leg is shown at the head and foot end 26,28. The support legs 30-34 are also designed as hollow profile square tubes. The support legs 30-34, together with the guide elements 20-24, in which they are guided so as to be longitudinally displaceable, form the telescopic legs 36-40 of the bed 10. The support legs 30-34 have roller holders 42 at their lower ends, which are mounted on the support legs 30-34 so as to be rotatable about axes running in the extension of the support legs. Each roller holder is provided with a roller or a pair of rollers 44, which are mounted on the roller holders 42 so as to be rotatable about a horizontal axis of rotation. At the head end 26 and at the foot end 28 there are electric motors, indicated at 46 in Fig. 1, which form the drive for height adjustment, i.e. for extending and retracting the support legs 30-34 from and into the guide elements 20-24. The two electric motors 46 are electrically connected to a control unit 48, to which an operating unit 50 with a plurality of operating buttons 52, 54, 56 is also connected.

Each leg 36-40 of the bed 10 is provided with a braking device 58 which is arranged inside the support legs 30-34. The braking device 58 located in the support leg 32 is explained in more detail below with reference to Fig. 2.

The braking device 58 has a braking element 60 designed as a tappet, which extends parallel to the support leg 22 through the latter. The braking element 60 also extends through the roller holder 42 mounted on the support leg 32, the lower end of the braking element 60 being located between the roller holder 42 and the base 64 on which the bed 10 rests. This end 62 is provided with a rubber brake block 66. In the area of its upper end 68, which is located at the level of the inner upper end 70 of the support leg 62, the braking element 60 extends through a passage 72 which is firmly connected to the support leg 32. Below the passage 72, a radially projecting support ring 74 is attached to the braking element 60, to which a pre-tensioning helical compression spring 76 with

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at one end, the other end of this spring 76 resting on the passage 72. In the area of the lower end of the support leg 32, a stop element 78 is fastened to the braking element 60, which is arranged inside the support leg 32 above the roller holder 42. This stop element 78 is located near the closed lower end 80 of the support leg 32, through which the braking element 60 extends. The end 68 of the braking element which projects upwards over the passage 72 is widened and has shoulder stops 82 which can be brought into contact with the passage 72. A driver rod 86 is fastened to the upper end 84 of the guide element 22, which projects into the support leg 32 from above and extends into it. The driver rod 86 has a stop 88 at its free end, which cooperates with an extension 90 at the upper end 68 of the braking element 60 in a manner to be described below.

As already briefly mentioned above, the motors 46 are part of a lifting device 92 which is housed in the head end 26 and the foot end 28 of the bed frame 12. The lifting device 92 is designed identically in both ends 26, 28 of the bed frame 12; the structure of the lifting device at the foot end 28 is explained in more detail below with reference to Fig. 2.

The lifting device 92 has a spindle 94 which is mounted on the crossbar 18 of the bed frame 14 and on a strut 96 connecting the upper ends 84 of the guide elements 22, 24, each rotatably and secured against axial displacement. The motor 46 is flanged to the crossbar 18 and drives the spindle 94. The spindle 94 is in threaded engagement with a connecting element 98, on which two control levers 100 are articulated. These control levers 100 are connected at their ends facing away from the connecting element 98 to diamond-shaped 0 pivot levers 102, 104. The pivot lever 102 is mounted rotatably about a pivot axis 106 of a fitting 107 arranged on the guide element 24, which pivot axis is parallel to the longitudinal and transverse bars 16, 18, while

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the other pivot lever 104 is mounted so as to be rotatable about a pivot axis 108 of a fitting 109 arranged on the guide element 22, which is parallel to the pivot axis 106. The free ends 110, 112 of the pivot levers 102, 104, which are opposite the pivot axes 106, 108, are connected to the widened upper ends 68 of the braking elements 60 via connecting levers 114. These connecting levers 114 are articulated to the free ends 110, 112 of the pivot levers 102, 104 and are guided at their other ends in elongated holes 116 which are formed in the widened upper ends 68 of the braking elements 60 and run in the longitudinal extension of the braking elements 60. For this purpose, the lever 114 is connected to a bolt 117 which extends through the elongated hole 116.

To raise the bed from the lowered position according to Fig. 2, the spindle 94 is driven in rotation by the motor 46, whereby the connecting element 98 is moved in the direction of the arrow 118 towards the cross member 18. The connecting element 98 takes the pivot levers 102,104 with it via the steering levers 100 so that they pivot about their axes of rotation 106,108 in the direction of the arrows 120. The fittings 107 and 109 for the axes of rotation 106,108 move linearly in the direction of the arrows 121. The free ends of the pivot levers 110,112 act on the braking elements 60 which, since they are supported on the support legs 32,34 via the stop elements 78 and the shoulder stops 82, lead to an extension movement of the support legs 32,34 and an upward movement of the guide elements. The individual phases of the pivoting movements of the pivot levers 102,104, the actuation of the 5 braking devices 58 and the linear movements of the support legs 30,34 and guide elements 22,24 are illustrated in Fig. 2 with solid arrows 120,121 for the case of raising the bed and with dashed arrows 120,121 for the case of lowering the bed and are explained in more detail below with reference to Figs. 2-7.

In the illustration according to Fig. 2, the support legs 32,34 are in their minimum extended positions so that the bed is in its lowest lifting height

. Furthermore, Fig. 2 shows the situation in which the braking device 58 is in its release position, in which the braking elements 60 are drawn into the support legs 32, 34 so far that the rubber blocks 66 are arranged above the base 64. In the release position, the braking elements 60 are drawn into the support legs 32, 34 against the force of the preload springs 76 and held there. This is done by the pivot levers 102, 104, which assume their uppermost pivot positions and pull the braking elements 60 up against the force of the springs 76 via the connecting levers 114. If the motor 46 is activated in this situation, the pivot levers 102, 104 pivot in the direction of the arrows 120. In the first phase of this pivoting movement, the braking elements 60 can move in the direction of the base 64 due to the force of the springs 76 until the rubber brake blocks 66 rest on it. This position is shown in Fig. 4. In this situation, the stop element 78 of the braking element 60 and the shoulder stops 82 are still slightly spaced from the lower closed end 80 of the support leg 32 or from its passage 72. The braking device 58 is now in its locking position in which it secures the bed 10 against movement when it is in the lowered state.

0 During the further pivoting movement of the pivot lever 102 in the direction of the arrow 120, the connecting lever 114 is first moved within the elongated hole 116 until it rests against the lower limit of the hole 116. From now on, the pivot lever 102 presses against the braking element 60 via the connecting lever 114 and via this against the base 64. The braking element 60 is supported via its shoulder stops 82 on the passage 72 and via its stop element 78 on the lower end 80 of the support leg 32. The result of this is that the pivot lever 102 now pivots about its free end 110 and is thus raised at its opposite end, which is rotatably connected to the opposite guide element 24, 0 taking the guide element 24 with it and lifting it. The pivot lever 104, which rests with its free end 110 on the braking element 60 in the support leg 34, has the same effect on the guide element 22, so

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that it is raised relative to the support leg 32. As a result, the support legs 32, 34 move out of the guide elements 22, 24 by lifting them (see Fig. 5). During this phase of the upward movement of the bed 10, the braking devices 58 remain in their locking positions, since the braking elements 60 with their rubber brake blocks 66 continue to rest on the base 64 and raise the rollers 44 slightly.

Towards the end of the upward displacement of the guide elements 22,24 or towards the end of the support legs 32,34, the situation shown in Fig.

6. In this situation, the stop 88 of the driving rod 86, which was moved upwards out of the support leg 32 when the guide element 22 was raised, comes into contact with the extension 90 of the braking element 60. If the two pivoting levers 102, 104 are pivoted beyond the position shown in Fig. 6 in the direction of the arrows 120, the driving rod 86 takes the braking element 60 with it against the force of the preload spring 76, so that the brake block 66 lifts off the base 64 and the braking device 58 is moved into its release position (see Fig. 7). Fig. 6 is therefore the uppermost extended position of the bed 10, in which the bed 10 is secured against displacement by the braking devices 58. This position is also shown in Fig. 3 0.

The individual phases when lowering the bed 10 from the highest lifting position with the brakes released to the lowest lowering position with the brakes also released are reversed to the process sequence described above. A detailed description is therefore not required here.

By the above-mentioned coupling of the free ends 110 of the pivot levers 102,104 with the braking elements 60 via the connecting levers 114 guided in the elongated holes 116, the movement of the free ends 110 of the pivot levers 102,104, which move along curved movement paths (indicated in Fig. 3 at 128), is compensated in order to move the support legs 30-34 or the

guide elements 20-24 to be able to move linearly. An alternative connection of the pivot levers 102,104 with the widened ends 68 of the brake elements 60 is shown in Fig. 8. According to this alternative, the free ends 110 of the pivot levers (the pivot lever 102 is shown in Fig. 8) have elongated holes 124 which extend approximately transversely to the pivoting movement of the free ends 110 of the pivot levers. A bolt 126 is movably guided in each of these elongated holes 124, which also extends through the elongated hole 116 of the brake element 60 to which the relevant pivot lever 102,104 is coupled.

The figures depict the situation in which the acting elements 110 of the pivot levers 102, 104 act on the support legs 30-34 via the braking elements 60 (at 82 and 78) in order to cause the support legs 30-34 and the guide elements 20-24 to move apart. However, it is also conceivable that the acting elements 110 of the pivot levers 102, 104 rest directly on the support legs 30-34 (e.g. at 128) in order to achieve the movement apart. In this case, the braking elements 60 are moved into the locking position by the force of the springs 76 when the actuators 110 of the pivot levers 102, 104 are in contact with the support legs 30-34, from which they can be moved via the driver rod 86 0 against the force of the spring 76 into the release position when the guide elements 20-24 and the support legs are moved sufficiently far apart (maximum extension position). The connecting bolts 117 between the connecting levers 114 and the upper end 68 of the braking elements 60 are thus in the maximum extended position when the pivoting levers 102, 104 are in contact with the support legs 30-34 and when the braking elements 60 are in the locking position, at a distance from the lower end of the elongated hole 116 facing the shoulder stops 82, so that the braking elements 60 are moved upwards by the upwardly moving guide elements 20-24.

In the minimum extension position of the support legs 30-34 with the brake device still in the release position, the pivot levers 102,104

via the connecting levers 114, the brake elements 60 are held in the raised position at a distance from the base 64 against the force of the spring 76. At the beginning of the pivoting movement of the pivot levers 102,104, these release the brake elements 60 so that they rest on the base 64 (locking position of the braking device). Even before the connecting bolts 117 reach the lower ends of the elongated holes 116, the acting elements 110 of the pivot levers 102,104 come into contact with the support legs 30-34 (which can occur, for example, at 128).

As mentioned above, the bed 10 is locked when the braking device 58 is in the locking positions by the brake blocks 66 of the braking elements 60 resting on the base 64. However, the bed 10 can also be locked by the braking elements pressing against the running surfaces of the rollers 44 and additionally locking the pivot bearings of the roller holders 42 on the support legs 30-34. A possible construction for such a braking mechanism is shown in Figs. 9 and 10, the parts of this braking mechanism which correspond to the parts of the braking devices 58 in Figs. 1 to 7 being identified by the same reference numerals.

As already explained above, identical lifting mechanisms are located in both the head section 26 and the foot section 28 of the bed 10. Both drive motors 46 are controlled synchronously to move the height of the bed 10, which is done automatically by the control unit 48. If necessary, the drive motors 46 can be controlled separately in order to move the entire bed 10 into an inclined position to place the patient in a shock position.

The user-friendly operation of the bed 10 0 will be discussed below with reference to Fig. 1, which shows an enlarged view of the control unit 50. The switches 52 of the control unit 50 serve, for example, to bring the (not shown) multi-part slatted frame of the bed 10 into the most varied positions. In contrast, the switches

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or buttons 54,56 of the upward and downward movement of the bed 10. For the following considerations it is assumed that the bed 10 is in its lowest position and that the braking devices 56 are in their release positions. If, for example, the bed is to be moved, the button 54, which must also be operated to move the bed 10 upwards, is operated. As a result, the drive motors 46 are activated so that the pivot levers 102,104 pivot in the direction of the arrows 120. In the first phase of this pivoting movement, only the braking devices are moved to their release positions. As soon as the brake blocks 66 have touched the base 64 and the braking elements 60 are in contact with the support legs 30-34 via the stop elements 78 and the shoulder stops 82, which can be detected by corresponding switches, the drive motors 46 are automatically switched off. If the button 54 is pressed again, the bed 10 is moved upwards, whereby the operator can select the height himself by releasing the button 54. If the operator keeps the button 54 pressed until the bed has reached the position shown in Fig. 3 or 6, the drive motors 46 are again forced to shut down. The state shown in Fig. 3 and 6 can be detected, for example, by a switch which responds when the stop 88 of the drive rod 86 rests against the extension 90 of the braking element 60. As a result of this forced shutdown, the bed is automatically moved to its highest position, in which it is still braked by the braking devices. By pressing the button 54 again, the pivot levers 102, 104 are then pivoted further in the direction of the arrows 120 in order to move the braking devices into the release positions.

By pressing button 56 in a manner similar to pressing button 54, the bed can be moved from the raised, non-braked position to the lowered, non-braked position, whereby the drive motors 46 are forced to shut off when the braking devices are in their locking positions in the raised position and the bed is in

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the braking devices located in the locking positions are lowered to the lowest position.

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Claims (38)

1. Height-adjustable bed, especially hospital or nursing bed, with - a bed frame ( 12 ) which has a frame ( 14 ) with guide elements ( 20-24 ) attached to it, in which support legs ( 30-34 ) with rollers ( 44 ) for moving the bed frame ( 12 ) are slidably guided, - a lifting device ( 92 ) for moving the support legs ( 30-34 ) and the guide elements ( 20-24 ) relative to each other between a minimum extension position and a maximum extension position, - wherein at least one of the support legs ( 30-34 ) is associated with a braking device ( 58 ) which can be transferred into a locking position in which the bed frame ( 12 ) cannot be moved and into a release position in which the bed frame ( 12 ) can be moved, - wherein the braking device ( 58 ) can be moved into the locking position and into the release position under the control of the lifting device ( 92 ), in such a way that when the support leg ( 32 ) is in the minimum extended position and the lifting device ( 92 ) is activated, the latter first moves the braking device ( 58 ) from the release position to the locking position and then extends the support leg ( 32 ), that the braking device ( 58 ) remains in the locking position during the extension movement of the support leg ( 32 ) until it reaches its maximum extended position or an intermediate position before the maximum extended position of the support leg, and that the lifting device ( 92 ) moves the braking device ( 58 ) from the locking position to the release position when activated after the maximum extended position or the intermediate position of the support legs has been reached. 2. Bed according to claim 1, characterized in that the lifting device ( 92 ) for extending the support legs ( 30-34 ) can be activated by actuating a first switch ( 54 ) and that the lifting device ( 92 ) switches off automatically when the maximum extension position or the intermediate position of the support legs ( 30 , 34 ) is reached, so that the braking device ( 58 ) remains in its locking position. 3. Bed according to claim 2, characterized in that the lifting device ( 92 ), which is automatically switched off when the maximum extension position or the intermediate position of the support legs is reached, can be activated by actuating a switch, in particular by repeatedly actuating the first switch ( 54 ) to transfer the braking device ( 58 ) from the locking position to the release position. 4. Bed according to one of claims 1 to 3, characterized in that the lifting device ( 92 ) for retracting the support legs ( 30-34 ) can be activated by actuating a second switch ( 56 ) and that the lifting device ( 92 ) switches off automatically when the minimum extension position of the support legs ( 30-34 ) is reached, so that the braking device ( 58 ) remains in its locking position. 5. Bed according to claim 4, characterized in that the lifting device ( 92 ) which is automatically switched off when the minimum extension position of the support legs is reached can be activated by actuating a switch, in particular by repeatedly actuating the second switch ( 56 ) to transfer the braking device ( 58 ) from the locking position to the release position. 6. Bed according to one of claims 1 to 5, characterized in that the braking device ( 58 ) has a braking element ( 60 ) for locking a castor ( 44 ) and/or a braking element ( 60 ) which can be placed on the base ( 64 ) on which the bed frame ( 12 ) rests via its castors ( 44 ). 7. Bed according to claim 6, characterized in that the braking element ( 60 ) is supported on at least one stop ( 72 ) of the support leg ( 32 ) in the locking position of the braking device and that the lifting device ( 92 ) has a pressing element ( 114 ) which moves relative to the guide element ( 22 ) and presses the braking element ( 60 ) against the stop ( 72 ) in order to extend the support leg ( 32 ). 8. Bed according to claim 7, characterized in that the guide element ( 22 ) has a driver ( 86 ) which, when the support leg ( 32 ) is in the maximum extended position or in the intermediate position, engages a stop ( 90 ) of the braking element ( 60 ) and, when the pressing element ( 114 ) moves after the maximum extended position or the intermediate position of the support leg ( 32 ) has been reached, moves the braking element ( 60 ) away from the supporting leg stop ( 72 ) to transfer the braking device ( 58 ) from the locking position to the release position. 9. Bed according to claim 7 or 8, characterized in that the braking element ( 60 ) is designed as a tappet with a brake block ( 66 ) arranged at one end ( 62 ) of the tappet. 10. Bed according to claim 9, characterized in that the plunger is movable parallel to the direction of displacement of the supporting leg ( 32 ). 11. Bed according to one of claims 1 to 10, characterized in that the lifting device ( 92 ) has for each pair consisting of a guide element ( 20-24 ) and a support leg ( 30-34 ) an automatically pivotable pivot lever ( 102 , 104 ), one end of which is rotatably mounted on the frame ( 14 ) and/or a guide element ( 20-24 ) of the bed frame ( 12 ) and the other end ( 110 ) of which acts on a support leg ( 30-34 ). 12. Bed according to claim 11, characterized in that the bed frame ( 12 ) has a head end ( 26 ) with two guide elements ( 20 ) and two support legs ( 30 ) and a foot end ( 28 ) with two guide elements ( 22 , 24 ) and two support legs ( 32 , 34 ) and that the pivot levers ( 102 , 104 ) are each alternately mounted at their one ends so as to be rotatable on the guide elements ( 20-24 ) and act with their other (acting) ends ( 110 ) on the support legs ( 30 , 34 ) at the head end ( 26 ) or foot end ( 28 ) of the bed frame ( 12 ). 13. Bed according to claim 11 or 12, characterized in that each of the two pivot levers ( 102 , 104 ) of the head or foot end ( 26 , 28 ) is coupled in an articulated and/or displaceable or movable manner, in particular via a respective link lever ( 100 ), to a connecting element ( 98 ) which is linearly displaceable by a motor-driven spindle ( 94 ) which extends between the two guide elements ( 20-24 ) of the head end ( 26 ) or the foot end ( 28 ) parallel to the guide elements ( 20-24 ) and is mounted rotatably and secured against axial displacements on the head end ( 26 ) or the foot end ( 28 ) of the bed frame ( 12 ). 14. Bed according to claim 13, characterized in that the pivot levers ( 102 , 104 ) consist of a flat material and have a greater width in the middle region than at the tapered ends. 15. Bed according to claim 14, characterized in that the pivoting levers ( 102 , 104 ) are substantially diamond-shaped. 16. Bed according to one of claims 11 to 15, characterized in that the acting end ( 110 ) of the pivot lever ( 102 , 104 ) which is assigned to the support leg ( 32 ) provided with the braking device ( 58 ) is coupled in an articulated and displaceable manner to the braking element ( 60 ). 17. Bed according to claim 16, characterized in that the braking element ( 60 ) has an elongated hole ( 116 ) extending in its direction of movement, in which one end of a connecting lever ( 114 ) is guided, the other end of which is connected in an articulated manner to the acting end ( 110 ) of the pivoting lever ( 102 , 104 ). 18. Bed according to claim 16, characterized in that the acting end ( 110 ) of the pivot lever ( 102 , 104 ) is provided with an elongated hole ( 124 ) running substantially transversely to the pivoting direction ( 120 ) of the pivot lever ( 102 , 104 ), in which the braking element is guided via a coupling element (bolt 126 ). 19. Bed according to one of claims 1 to 18, characterized in that the braking device is pre-tensioned into the locking position by means of a pre-tensioning spring ( 76 ). 20. Height-adjustable bed, especially hospital or nursing bed, with - a bed frame ( 12 ) which has a frame ( 14 ) with guide elements ( 20-24 ) attached to it, in which support legs ( 30-34 ) with rollers ( 44 ) for moving the bed frame ( 12 ) are slidably guided, - a lifting device ( 92 ) for moving the support legs ( 30-34 ) and the guide elements ( 20-24 ) relative to each other between a minimum extension position and a maximum extension position, - wherein at least one of the support legs ( 30-34 ) is associated with a braking device ( 58 ) which can be transferred into a locking position in which the bed frame ( 12 ) cannot be moved and into a release position in which the bed frame ( 12 ) can be moved, - wherein the braking device ( 58 ) has a braking element ( 60 ) which can be moved by the lifting device ( 92 ) when the support leg ( 32 ) is in the minimum extension position in order to transfer the braking device ( 58 ) from the release position to the locking position, wherein the braking element ( 60 ) rests on the support leg ( 32 ) and/or a stop ( 72 ) of the support leg ( 32 ) when the braking device ( 58 ) is in the locking position and a pressing element ( 114 ) of the lifting device ( 92 ), which can be driven by a drive device ( 46 ) of the lifting device ( 92 ) supported on the frame ( 14 ), presses against the braking element ( 60 ) and via this moves the support leg ( 32 ) and the guide element ( 22 ) relative to one another. 21. Bed according to claim 20, characterized in that the braking device ( 58 ) has a braking element ( 60 ) for locking a castor ( 44 ) and/or a braking element ( 60 ) which can be placed on the base ( 64 ) on which the bed frame ( 12 ) rests via its castors ( 44 ). 22. Bed according to claim 20 or 21, characterized in that the guide element ( 22 ) has a driver ( 86 ) which, when the support leg ( 32 ) is in the maximum extended position or in the intermediate position, engages a stop ( 90 ) of the braking element ( 60 ) and, when the pressing element ( 114 ) moves after the maximum extended position or the intermediate position of the support leg ( 32 ) has been reached, moves the braking element ( 60 ) away from the supporting leg stop ( 72 ) to transfer the braking device ( 58 ) from the locking position to the release position. 23. Bed according to one of claims 20 to 22, characterized in that the braking element ( 60 ) is designed as a tappet with a brake block ( 66 ) arranged at one end ( 62 ) of the tappet. 24. Bed according to one of claims 20 to 23, characterized in that the plunger is movable parallel to the direction of displacement of the supporting leg ( 32 ). 25. Bed according to one of claims 20 to 24, characterized in that the lifting device ( 92 ) has for each pair consisting of a guide element ( 20-24 ) and a support leg ( 30-34 ) an automatically pivotable pivot lever ( 102 , 104 ), one end of which is rotatably mounted on the frame ( 14 ) and/or a guide element ( 20-24 ) of the bed frame ( 12 ) and the other end ( 110 ) of which acts on a support leg ( 30-34 ). 26. Bed according to claim 25, characterized in that the bed frame ( 12 ) has a head end ( 26 ) with two guide elements ( 20 ) and two support legs ( 30 ) and a foot end ( 28 ) with two guide elements ( 22 , 24 ) and two support legs ( 32 , 34 ) and that the pivot levers ( 102 , 104 ) are each alternately mounted at their one ends so as to be rotatable on the guide elements ( 20-24 ) and act with their other (acting) ends ( 110 ) on the support legs ( 30 , 34 ) at the head end ( 26 ) or foot end ( 28 ) of the bed frame ( 12 ). 27. Bed according to claim 25 or 26, characterized in that each of the two pivot levers ( 102 , 104 ) of the head or foot end ( 26 , 28 ) is coupled in an articulated and/or displaceable or movable manner, in particular via a respective link lever ( 100 ), to a connecting element ( 98 ) which is linearly displaceable by a motor-driven spindle ( 94 ) which extends between the two guide elements ( 20-24 ) of the head end ( 26 ) or the foot end ( 28 ) parallel to the guide elements ( 20-24 ) and is mounted rotatably and secured against axial displacements on the head end ( 26 ) or the foot end ( 28 ) of the bed frame ( 12 ). 28. Bed according to claim 27, characterized in that the pivot levers ( 102 , 104 ) consist of a flat material and have a greater width in the middle region than at the tapered ends. 29. Bed according to claim 28, characterized in that the pivoting levers ( 102 , 104 ) are substantially diamond-shaped. 30. Bed according to one of claims 25 to 29, characterized in that the acting end ( 110 ) of the pivot lever ( 102 , 104 ) which is assigned to the support leg ( 32 ) provided with the braking device ( 58 ) is coupled in an articulated and displaceable manner to the braking element ( 60 ). 31. Bed according to claim 30, characterized in that the braking element ( 60 ) has an elongated hole ( 116 ) extending in its direction of movement, in which one end of a connecting lever ( 114 ) is guided, the other end of which is connected in an articulated manner to the acting end ( 110 ) of the pivoting lever ( 102 , 104 ). 32. Bed according to claim 30, characterized in that the acting end ( 110 ) of the pivot lever ( 102 , 104 ) is provided with an elongated hole ( 124 ) running substantially transversely to the pivoting direction ( 120 ) of the pivot lever ( 102 , 104 ), in which the braking element is guided via a coupling element (bolt 126 ). 33. Bed according to one of claims 20 to 32, characterized in that the braking device is pre-tensioned into the locking position by means of a pre-tensioning spring ( 76 ). 34. Height-adjustable bed, in particular hospital or nursing bed, with - a bed frame ( 12 ) having a frame ( 14 ) with guide elements ( 20-24 ) attached thereto, in which support legs ( 30-34 ) with rollers ( 44 ) for moving the bed frame ( 12 ) are slidably guided, and - a lifting device ( 92 ) for moving the support legs ( 30-34 ) and the guide elements ( 20-24 ) relative to each other between a minimum extension position and a maximum extension position, - wherein the lifting device ( 92 ) has for each pair consisting of a guide element ( 20-24 ) and a support leg ( 30-34 ) an automatically pivotable pivot lever ( 102 , 104 ), one end of which is rotatably mounted on the frame ( 14 ) and/or a guide element ( 20-24 ) of the bed frame ( 12 ) and the other end ( 110 ) of which acts on a support leg ( 30-34 ). 35. Bed according to claim 34, characterized in that the bed frame ( 12 ) has a head end ( 26 ) with two guide elements ( 20 ) and two support legs ( 30 ) and a foot end ( 28 ) with two guide elements ( 22 , 24 ) and two support legs ( 32 , 34 ) and that the pivot levers ( 102 , 104 ) are each alternately mounted at their one ends so as to be rotatable on the guide elements ( 20-24 ) and act with their other (acting) ends ( 110 ) on the support legs ( 30 , 34 ) at the head end ( 26 ) or foot end ( 28 ) of the bed frame ( 12 ). 36. Bed according to claim 34 or 35, characterized in that each of the two pivot levers ( 102 , 104 ) of the head or foot end ( 26 , 28 ) is coupled in an articulated and/or displaceable or movable manner, in particular via a respective link lever ( 100 ), to a connecting element ( 98 ) which is linearly displaceable by a motor-driven spindle ( 94 ) which extends between the two guide elements ( 20-24 ) of the head end ( 26 ) or the foot end ( 28 ) parallel to the guide elements ( 20-24 ) and is mounted rotatably and secured against axial displacements on the head end ( 26 ) or the foot end ( 28 ) of the bed frame ( 12 ). 37. Bed according to claim 36, characterized in that the pivot levers ( 102 , 104 ) consist of a flat material and have a greater width in the middle region than at the tapered ends. 38. Bed according to claim 37, characterized in that the pivoting levers ( 102 , 104 ) are substantially diamond-shaped.