JPH055506B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Prior Art and Problems to be Solved by the Invention] There have been many examples of hydraulic hospital beds and treatment tables. These devices include the bed itself,
Hydraulic cylinders are used to raise and lower the head side adjustment part and the leg side adjustment part. There are also electrically operated hospital beds. In the case of electrically operated beds, the head and leg sections can be lowered rapidly in an emergency by disengaging the mechanical drive members. Hydraulically operated beds generally do not have this capability.
This is because the hydraulic rods are usually connected directly to the head and leg sections, which generally slows the rate of descent, even in emergency situations where cardiopulmonary resuscitation (CPR) is required. It's for a reason.

U.S. Pat. No. 4,038,709 shows a hospital bed with a dual hydraulic system operable by either compressed air or foot-operated pumps. The bed has mechanical means for rapidly lowering the head and leg sections in an emergency.

U.S. Pat. No. 3,149,349 shows another configuration of a hydraulically driven hospital bed, and U.S. Pat. No. 3,281,141
The number indicates a hydraulically operated surgical operating table. The surgical table is powered by both an electric pump and a foot-operated pump. US Pat. No. 2,217,783 shows yet another hydraulically operated operating table. The operating table in this case has a dual pump system for hydraulic power supply, including an electric pump and a manual pump. U.S. Pat. No. 4,559,655 shows a powered hospital bed having means for rapidly lowering the head and leg sections in an emergency.

[Means to solve the problem]

The present invention is an improved hydraulic drive system for a hospital bed. Hospital beds are of the type that have a generally rigid support cradle mounted from a plurality of movable patient support surfaces. The patient support surfaces, commonly referred to as the cranial, femoral and leg sections, are movable between horizontal and raised positions.
The improved hydraulic drive uses cylinders with telescoping rods attached to movable patient support surfaces for articulating those surfaces. The cylinder is actuated by a hydraulic power source that receives hydraulic fluid from a hydraulic fluid tank and returns hydraulic fluid to the tank. Control valve means are connected within the hydraulic circuit for introducing and discharging hydraulic fluid.
The cylinders can be selectively actuated to articulate the various parts. Furthermore, in an emergency, the hydraulic fluid can be drained from the cylinder to the hydraulic fluid tank without using the control valve circuit to lower the cranial, femoral and leg sections more rapidly than would be possible in normal operation via the control valve circuit. Emergency bypass hydraulic circuit means are provided to allow the lowering of the vehicle.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 is from Hill-Rom Company Inc.
A hospital bed 10 of the type sold under the trade name CenturyCC Hospital Bed is shown. 1st
Bed 10 is shown with most of the decorative moldings and coverings removed to more clearly depict the hydraulic system of the present invention. Bed 10 includes a base frame 12 comprised of longitudinal members 14 and 16 joined together by a pair of transverse members. Note that only one transverse member 18 is shown in FIG. Four large casters 20 are attached to the base frame 12. Although only two of the four casters are shown in FIG. 1, it will be apparent that two opposing casters located on opposite sides serve to movably support base frame 12. Two vertically extending, generally triangular bosses 22 and 24 are attached to the foot end of the bed 10.
These bosses 22 and 24 cantilever support arms 26
Used as a rotating mounting part. Cantilevered arm 26 connects bosses 22 and 24 via pivot pin 28.
and is attached at the end not on the side of the pivot pin 28 to two brackets, only one of which 30 is shown in FIG. Brackets 30 and corresponding brackets located on opposite sides (not shown) are connected to two longitudinal frame members 3.
2 and 34. Frame members 32 and 34 are joined together by transverse members 36 and 38 to form a rigid support that moves with bracket 30. Bracket 30 has boss 22
A stabilizing arm 40 is further mounted which is rotatably mounted to. Stabilizing arm 40 moves with cantilever support arm 26 and functions to stabilize the cantilever support arm 26 as it moves. Cantilevered arm 26 has its clevis-shaped attachment portion 46
It is driven by a hydraulic cylinder 42 having a telescoping rod 44 attached to it. Clevis-shaped fitting 46 has a pin 48 connecting it to rod 44. The root of the hydraulic cylinder 42 is attached to the longitudinal members 14 and 16. rod 4
It will be seen that as 4 extends and retracts, its telescoping motion is transmitted to cantilevered arm 26 via clevis-shaped mount 46 and pin 48. The expansion and contraction of the rod 44 causes the cantilever support arm 26 to move up and down. The position shown in FIG. 1 is the fully extended position, ie, above the cantilevered arm 26. When the rod 44 is retracted, the cantilever arm 26 is lowered and the frame attached to the bracket 30 is lowered accordingly.

As with many hospital beds, the bed 10 includes means for articulating the parts of the bed so that the patient support surface can assume various positions. The patient support surface itself is supported by longitudinal frame members 32 and 34. The patient support surface is composed of several elements, firstly the fixed seat portion 50 is completely fixed. The head portion 52 of the bed 10 adjacent to the head typically supports the patient's upper body and is the portion of the longitudinal frame member 3 that is adjacent to the head of the bed 10.
2 and 34 from the fully lowered position.
It can be articulated to the fully erect position shown in the figure. The head side portion 52 is raised and lowered via a crank mechanism 54.
is a hydraulic cylinder 5 having a telescoping rod 58 attached thereto and driving a crank mechanism.
6. Note that the hydraulic cylinder 56 is connected to the longitudinal frame member 32 via a bracket 60.
mounted on. Although only one hydraulic cylinder 56 is shown in FIG. 1 as a means of driving the head section 52, one hydraulic cylinder is supported by the longitudinal frame member 32 and the other by the longitudinal frame member 34 on the opposite side. Preferably, two hydraulic cylinders are used. Although the second hydraulic cylinder is not shown in FIG. 1, this hydraulic cylinder will be described later when explaining the operation of the hydraulic circuit of the present invention. Although the function of raising the head section would be sufficient to be provided by only one hydraulic cylinder 56, using two hydraulic cylinders would make the raising action smoother and the crank mechanism 5
The number of times 4 gets stuck is also reduced. The patient support surface is further comprised of two parts: a thigh section 62 and a leg section 64. Thigh section 62 and leg section 64 are pinned together for movement in unison and are also pinned to stationary seat section 50 for liftability as shown in FIG. Actuation of the thigh section 62 causes the leg section 64 to correspondingly rise. The thigh section 62 is raised and lowered by a hydraulic cylinder 66 having a telescoping rod 68 attached thereto. In response to the expansion and contraction of rod 68,
Thigh portion 62 and leg portion 64 also move. In order not to unnecessarily complicate the drawing, the hydraulic pipes and valves necessary for the operation of this hydraulic system are not shown in FIG. 1st
The figure shows a hydraulic fluid tank 70 supported between two vertical bosses 22 and 24. Boss 22 and 2
4, a power pack 72 and a foot-operated pump 102 are also shown, which provide the power necessary for the electrical pumping of the hydraulic system. Also shown in FIG. 1 is a foot-operated pedal for operating the hydraulic system of the present invention in manual mode. That is,
The pedal/lever 74 is marked such that when the lever 74 is depressed, hydraulic pressure is supplied to the hydraulic system by operation of the foot-operated pump 102. The hydraulic pressure thus supplied is guided by the manual switching valve 76. The manual switching valve is used only in manual mode, as indicated with respect to the description of the hydraulic circuit of the present invention. The manual switching valve 76 and the emergency valve 136 are operated by a rotatable dial 88. A release lever 78 is provided to reduce or release the hydraulic pressure supplied to the hydraulic system by the manual pump activation lever 74. Release lever 78
By stepping on the button, hydraulic pressure can be released from the hydraulic system, so that the components of the hydraulic system return to their original state.

Figures 2, 3 and 4 show CPR of the present invention.
Indicates the operating mode. Hydraulic systems capable of both manual operation and power-based operation are known in the art. However, one of the problems with conventional hydraulic systems is their inability to perform CPR modes, ie, modes in which the patient assumes a flat position on a relatively hard surface for a short period of time. In FIG. 2, a patient 80 lying on the supine surface of the bed 10 of the present invention as shown in FIG. 1 has been raised to approximately the position shown in FIG. As a configuration normally taken when using a bed, the headboard 82
A foot plate 84 is added to the bed 10. The normal operation of the bed 10 is to raise the thigh section 62 and leg section 64 for about 20 seconds and return them from the raised position shown in FIG. 2 to the flat position for about 20 seconds. The cephalic portion 52 will be approximately 30 mm in height by the time it reaches the fully erect position shown in FIG.
Similarly, it takes about 30 seconds to return to a completely flat position.
It takes seconds. Therefore, the patient 80's heartbeat stops,
cranial area 52 if immediate CPR is required.
The time required to lower the thigh portion 62 and leg portion 64 is approximately 30 seconds. This time is extremely long in an emergency and needs to be improved.

FIG. 3 shows the patient 80 having reached a fully flat position from the position shown in FIG. According to the present invention, when in emergency mode, the bed can be moved from the position shown in FIG. 2 to the position shown in FIG. 3 in about 4 to 8 seconds. This includes a special valve in the hydraulic circuit and a rotatable dial 88.
This is possible by specially setting . FIG. 4 shows that one of the setting marks on the rotatable dial 88 displays the letters "CPR" in the symbol window 86 of the dial. Rotatable dial 88
is actuated by a lever 89 that is easy to grasp by a nurse or other medical staff. Manual switching valve 76
actually only controls the function of the bed, whereas a separate valve 136, described in detail below with respect to FIG. 5, controls the emergency lowering function. However, for convenience, the dial 88 and lever 89
is configured to display and control CPR.
The CPR emergency lowering function is performed by moving lever 89 to either end position of rotatable dial 88 and holding it there. To prevent this feature from being started accidentally,
Lever 89 must be held in place by hand. When the lever 89 is released, it automatically moves to the other position of the manual switching valve 76. As the rotary dial 88 is moved to other positions dictated by the manual switching valve 76, other indications such as head, knee or hi/low will appear in the symbol window 86 as shown in FIG. 4A. Further, as shown in FIG. 4A, the CPR symbol is located at both ends of the symbol window 86. Note that the overall height of the bed 10 remains unchanged while moving from the position shown in FIG. 2 to the position shown in FIG. 3. In the present invention, the bed 1
The pressure of the hydraulic cylinder 42 that moves the 0 up and down is not rapidly released. Rather, the only requirement is to keep the patient flat for a very short period of time to be able to apply CPR.

FIG. 5 shows the hydraulic circuit of the present invention in the form of a standard hydraulic circuit diagram. The power pack 72 is comprised of an electric motor and a pump that supplies pressure to a line 90 that is split to provide pressure to three generally identical solenoid operated valves 92, 94 and 96, as shown. Solenoid valve 92, which operates as an extension valve, is a normally closed valve that can route hydraulic pressure from line 90 to hydraulic cylinder 42 via outlet line 98, and hydraulic cylinder 42 is closed when solenoid valve 92 is actuated. Raise the bet by 10. The hydraulic cylinder 42 is a solenoid valve 9
2 and outlet line 98, it may also be supplied with hydraulic fluid via line 100, which is connected to manual switching valve 76. Manual switching valve 76 is rotatable to direct hydraulic fluid from foot-operated pump 102 to any one of the hydraulic cylinders. Both foot-operated pump 102 and power pack 72 receive hydraulic fluid from hydraulic fluid tank 70.
Hydraulic fluid tank 70 is used as a source of hydraulic fluid for the entire hydraulic system. Hydraulic fluid passes through filter 104 before entering power pack 72. A separate branch line 106 is provided that connects the hydraulic fluid tank 70 to the foot-operated pump 102. As previously mentioned, foot-operated pump 102 may be operated by foot pedal/lever 74. A normally closed check valve 108 bypasses this pump 102. The normally closed check valve is the release lever 78
It is sufficient if it is released by the operation of . Release lever 78
When normally closed check valve 108 is opened by operation of Return to tank 70.

Next, the hydraulic cylinder 42 will be explained. The hydraulic cylinder 42 is a single-acting type. That is, hydraulic cylinder rod 44 is extended by applying pressure to hydraulic cylinder 42 through outlet line 98. Next, when the solenoid valve 92 is closed,
Pressure is contained in outlet line 98 and rod 4
4 maintains the stretched state. When rod 44 is retracted, normally closed solenoid valve 110 is actuated to return hydraulic fluid along outlet line 98, except that:
Hydraulic fluid then flows into solenoid valve 110 via branch line 112 and from there returns to hydraulic fluid tank 70 via branch line 114. With pressure confined in outlet line 98 and branch line 112 and with solenoid valves 92 and 110 both closed, rod 44 remains in its previously held position. When solenoid valve 110 is actuated, rod 44 slowly retracts due to its weight, thereby lowering cantilever support arm 26 and lowering the entire bed toward the floor. It can be seen that this function is essentially the same for the foot-operated pump 102. Manual switching valve 76 is configured to direct pressure from foot-operated pump 102 to hydraulic cylinder 42 . When the rod 44 reaches the desired extended position, the foot-operated pump 102 is deactivated and the line 100 is pressurized. When the release lever 78 is pushed down to release pressure, the normally closed check valve 10
8 is opened, allowing hydraulic fluid to return to the hydraulic fluid tank 70 via line 100 and branch line 106.

The operation of all hydraulic cylinders 42, 56 and 66 is substantially the same as described above. Solenoid valves 92, 94 and 96 are all identical and may be operated from control elements located on the guardrail or foot of bed 10. Pump outlet line 90 is also connected to the inlet of a normally closed solenoid valve 94, which acts as a retraction valve. Lines 116 exiting the normally closed solenoid valve 94 are connected to hydraulic cylinders 66 that actuate the thigh and leg portions of the patient support surface. In the electric mode of operation, pressure from the pump flows through outlet line 90 with solenoid valve 94 actuated to its open position and then through line 116 to hydraulic cylinder 6.
6 to extend the rod 68. As a result, thigh portion 62 and leg portion 64 move to the upright position shown in FIG. When solenoid valve 94 is closed, pressure remains in line 116 and rod 68 retains its previously occupied position. Rod 6
An electrically operated normally closed solenoid valve 118 is opened to retract the thigh section 8 and return the thigh section 62 and leg section 64 to a flat position. This solenoid valve 118 is connected to a branch line 120 that is connected to line 116. The outlet of the solenoid valve 118 is connected to the hydraulic fluid tank 7 via a hydraulic line 122.
Connected to 0. Thus, when solenoid valve 118 is actuated, the pressure within hydraulic cylinder 66 directs hydraulic fluid into lines 116, 120 and 1.
22 to the hydraulic fluid tank 70. As a result, rod 6
8 can be pulled in. Another mode of operation of the hydraulic cylinder 66 via the manual switching valve 76 is exactly similar to the operation previously described with respect to the hydraulic cylinder 42. The manual switching valve 76 is connected to the pedal 7
Operation of foot-operated pump 102 by 4 applies pressure within hydraulic cylinder 66 and is set to actuate or extend rod 68. When the check valve 108 is then opened via the release lever 78, this pressure is released and the hydraulic fluid is returned to the hydraulic fluid tank 70 via the branch line 106. Branch line 106 performs a dual function of supply and return for manual operating mode.

First, the hydraulic cylinder 5 operates the head side portion 52.
Although only one side of the cylinder 6 is shown, FIG. 5 shows an actual configuration consisting of two cylinders. These cylinders are designated 56 and 56'. Both hydraulic cylinders 56 and 56' are actuated simultaneously by solenoid valve 96. Solenoid valve 96 is connected to power pack 72 via outlet line 90. Solenoid valve 96 is a normally closed valve, and actuation of this valve directs hydraulic fluid into inlet line 124.
and branch connectors 125 and 126 into both hydraulic lines 56 and 56' simultaneously. Actuation of hydraulic cylinders 56 and 56' causes respective rods 58 and 58' to extend and raise head portion 52 as shown in FIG. Again, pressure may be contained in inlet line 124 and branch connectors 125 and 126 by closing solenoid valve 96 after pressurized fluid is supplied and rods 58 and 58' are extended. When releasing the pressure acting on hydraulic cylinders 56 and 56', normally closed solenoid valve 128 is opened. As a result, the hydraulic fluid contained in the hydraulic cylinders 56 and 56' can flow through the inlet line 124 and the branch connector 130 connected to the solenoid valve 128. When solenoid valve 128 opens, hydraulic fluid enters line 132 and thence back to hydraulic fluid tank 70 .

Solenoid valves 94, 96, 118, 128,
The manual switching valve 76 and the check valve 108 are all
It acts as a first hydraulic control valve means for controlling the functions of the head section 52, thigh section 62, leg section 64 and the actuating hydraulic cylinders associated therewith. The solenoid valves 98 and 110, the manual switching valve 76, and the check valve 108 are connected to the hydraulic cylinder 4.
It acts as a second hydraulic control valve means for controlling the second bed raising and lowering operation.

One of the important features of the invention is that the head section 52, thigh section 62 and leg section 64 can be lowered very quickly in an emergency. Solenoid valves 118 and 128 are fixedly adjusted to allow a certain amount of hydraulic fluid to flow when actuated. This flow rate is calculated to provide a relatively gradual drop in each section controlled by these valves. This eliminates unnecessary electrical stimulation and discomfort to the patient's body parts. However, in an emergency, maintaining the patient in a flat position must be considered over other considerations such as comfort and comfort. Therefore, a bypass circuit is provided in case of an emergency. Bypass line 134 connects hydraulic cylinder 66 and
The CPR valve 136 is connected to the CPR valve 136. Emergency CPR valve 13
Reference numeral 6 is a normally closed valve actuated by a spring, and is a mechanical valve that allows operation whether the bed 10 is in the electrical operation mode or the manual operation mode. It is important that the emergency CPR valve 136 be manually operated to avoid problems associated with power outages or overpowering. Hydraulic cylinders 56 and 56' are also connected to emergency CPR valve 136 via bypass line 138.
connected to. Two bypass lines 134 and 138 are commonly connected to an emergency CPR valve 136 at the inlet. Emergency CPR valve 136 is a normally closed valve, and bypass lines 134 and 138 normally have no function. However, in the event of an emergency, medical staff can use the emergency CPR valve 136.
is operated, and as a result, the hydraulic cylinders 66, 56
and 56' immediately exits the cylinder and flows through bypass lines 134 and 138, past emergency CPR valve 136, and into branch line 1.
Returns to the hydraulic fluid tank 70 via line 140 connected to 06. Check valves 142 and 144
are connected to bypass lines 138 and 134, respectively, to prevent cross-flow of hydraulic fluid when emergency CPR valve 136 is opened. If check valves 142 and 144 are not provided,
From bypass line 134 to bypass line 138 (or from bypass line 138 to bypass line 134) when emergency CPR valve 136 opens
It would also be possible for pressurized fluid to escape.

As previously pointed out, the normal operating time of the hydraulic cylinder 66 also extends when the rod 68 is extended.
It also takes about 20 seconds to retract the rod 68. Typical operating time for hydraulic cylinders 56 and 56' is approximately 30 seconds. The size of the emergency CPR valve 136 is determined by the operation of this valve 136.
6, 56 and 56' are designed to fully retract in 4 to 8 seconds. That is, the patient would have to wait for approximately 30 seconds instead of the approximately 30 seconds that would have been had a solenoid valve system using solenoid valves 118 and 128 been used.
It can be moved from the position shown in FIG. 2 to the position shown in FIG. 3 in a short period of about 4 to 8 seconds. For such fast operation,
Use of the emergency CPR valve 136 imposes somewhat rapid movements on the components of the bed 10, but allows for rapid positioning of the patient for emergency procedures.

FIG. 6 shows a side guard 146 of the type commonly used with bed 10. side guard 1
Reference numerals 46 are of a type that takes half the length of the bed, and it is thought that two are usually provided on each side of the bed. The side guard 146 is attached to the support bracket 14
8 and 149 to the bed 10.
The support brackets are coupled so that the side guards 146 can pivot from a position above the longitudinal frame members 32 and 34 to a position below them. Side guard 146 has a generally continuous peripheral member 150 joined by web members 151, 152 and 153. Bed operating panel 154 is disposed between web members 152 and 153.

FIG. 7 shows bed operation panel 154 in more detail. The bed operation panel 154 is provided with several electrical switches that control various functions. When the nurse call switch 156 is pressed, a call is notified to the nurse station. Light switches 158 and 159 control interior and overhead lights. Head up switch 160, when operated, turns on power pack 72 and opens solenoid valve 96. As a result, the head section 52 is lifted by the action of the hydraulic cylinders 56 and 56'. Headdown switch 162 operates solenoid valve 128 to transfer hydraulic fluid to hydraulic fluid tank 70.
and lower the head portion 52. The knee-up switch 164 turns on the power pack 72,
Open the solenoid valve 94. As a result, the hydraulic cylinder 66 operates, causing the thigh portion 62 and the leg portion 6 to move.
Lift up 4. On the contrary, knee down switch 166
, the solenoid valve 118 is opened so that the hydraulic fluid returns to the hydraulic fluid tank 70 and the thigh section 62 and leg section 64 return to the horizontal position. When the bed up switch 168 is operated, the power pack 72 is turned on and the solenoid valve 92 is opened. As a result, the hydraulic cylinder 42 operates and raises the entire bed 10. When lowering the bed 10, the bed down switch 170 is operated. This causes solenoid valve 110 to open and return hydraulic fluid to hydraulic fluid tank 70 .

〔Effect of the invention〕

As described above, according to the hydraulic drive device according to the present invention, when returning the working fluid from the hydraulic cylinder to the hydraulic fluid tank in order to lower the head section, thigh section, and leg section, each section is normally A hydraulic circuit is used with a control valve whose flow rate is determined to be gradually lowered so that the patient is comfortably flat. In addition, in an emergency such as when a patient requires cardiopulmonary resuscitation, the control valve is bypassed,
Working fluid is returned from the hydraulic cylinder to the hydraulic fluid tank using an emergency bypass hydraulic circuit having an emergency CPR valve, which can pass a large amount of working fluid in a short period of time compared to the control valve. This allows each part to be lowered rapidly.

By making this CPR valve a manually operated valve, it is possible to quickly lower each part even in the event of a power outage.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the hospital bed of the present invention with most of the cover plates removed, and FIG.
FIG. 3 is a perspective view of the hospital bed of the present invention showing the patient in the upright position; FIG. 3 is a perspective view similar to FIG. 2 showing the patient in the supine position; FIG. A perspective view of the manual switching valve of the present invention, FIG. 4A
is a plan view of the symbol window in manual selection mode, FIG. 5 is a schematic circuit diagram of the hydraulic system of the present invention, FIG. 6 is a side view of the guardrail used in the hospital bed of the present invention, and FIG. 7 is a plan view of the bed function operation panel used in the hospital bed of the present invention. 10... Hospital bed, 12... Base frame, 32, 34... Longitudinal frame member, 3
6, 38... Lateral member, 42... Hydraulic cylinder, 44... Rod, 52... Head side portion, 56,
56'... Hydraulic cylinder, 58, 58'... Rod, 62... Thigh part, 64... Leg part, 66...
... Hydraulic cylinder, 68 ... Rod, 70 ... Hydraulic fluid tank, 72 ... Power pack, 92,9
4,96...Solenoid valve, 102...Foot operated pump, 108...Check valve, 110,11
8,128...Solenoid valve, 134...Bypass line, 136...Emergency CPR valve, 138...
Bypass line, 142, 144...check valve.

Claims (1)

Claims: 1. A generally rigid support pedestal having a plurality of movable patient support surfaces attached thereto, the movable patient support surfaces being movable from a generally horizontal position to an upright position and having a cephalad portion. In an improved hydraulic drive device for a hospital bed of the type comprising: a cephalic section, a femoral section and a leg section, the actuation rods are respectively coupled to the head section, the femoral section and the leg section; a plurality of hydraulic cylinders, each having a plurality of hydraulic cylinders, such that movement of the actuating rod causes movement of the head section, thigh section, and leg section; B. a source of pressurized hydraulic fluid connected to the hydraulic cylinders; a pressurized hydraulic fluid supply having an electrically driven pump and a dual power source capable of acting as a foot-operated pump; C a reservoir for said hydraulic fluid at approximately atmospheric pressure; D said pressurized hydraulic fluid supply. a source connected to an intermediate circuit between the reservoir tank and the hydraulic cylinder to direct and direct hydraulic fluid from the selected hydraulic cylinder to the selected hydraulic cylinder for extending and retracting the actuating rod; E. retracting said actuation rod more rapidly than when said control valve means is in use, thereby lowering said cranial, femoral and leg portions more rapidly; emergency bypass hydraulic circuit means for bypassing the control valve means and discharging hydraulic fluid from the cylinder to the reservoir tank; 2. The control valve means comprises: A. an electrically operated normally closed extension valve connected between each of the hydraulic cylinders and the electrically driven pump; B. each of the hydraulic cylinders and the electrically driven pump; a normally closed retraction valve connected between the storage tank and electrically operated; C connected between the hydraulic cylinder and the foot-operated pump, and connecting any one of the hydraulic cylinders from the foot-operated pump a manual switching valve that operates to direct hydraulic fluid to the manual switching valve; D connected to the manual switching valve and the storage tank, and when opened, the hydraulic cylinder connected to the manual switching valve drains the hydraulic fluid therein; 2. A hydraulic drive system as claimed in claim 1, comprising: a manually operated normally closed discharge valve operative to return water to said storage tank. 3. The hydraulic drive system of claim 2, wherein the head section is actuated by two hydraulic cylinders that operate in unison and are controlled by a single extension valve and a single retraction valve. 4A: a lifting hydraulic cylinder having a telescoping rod coupled to the rigid support frame; B: a base frame to which the lifting hydraulic cylinder is attached; C: the pressurized hydraulic fluid supply source; and the storage tank; The rigid support frame is selectively connected to an intermediate circuit with the lifting hydraulic cylinder and directs hydraulic fluid toward and from the lifting hydraulic cylinder to raise and lower the rigid support frame. and maintaining said rigid support cradle in its selected raised position when said emergency bypass hydraulic circuit means is actuated by not allowing hydraulic fluid to flow through said emergency bypass hydraulic circuit means. 2. The hydraulic drive system of claim 1, further comprising: second control valve means connected to. 5. The emergency bypass hydraulic circuit means: A. A manually operated normally closed emergency valve; B. Connected to an intermediate circuit between each of the hydraulic cylinders and the emergency valve, and allowing hydraulic fluid to flow out only from the hydraulic cylinders. The hydraulic drive device according to claim 1, comprising: a one-way check valve arranged as follows.