JPH11188064A - Device for adjusting height of wheelchair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly increase a wheelchair's height by means of a manual pump. SOLUTION: The hydraulic pump 40 consists of the first oil pass 61 that connects reservoir oil sac 53 of reservoir tank 42 with oil sac 47 at the side of piston, the first check bulb 71 that is settled in the first oil pass 61, the second oil pass 62 that connects oil sac 46 at the side of plunger made at a piston with the oil sac 47 at the side of piston. As the hydraulic pump 40 is pushed and drew, in both direction, oil is provided for the hydraulic actuator, so the level of the wheelchair can be up.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for adjusting the height of a wheelchair.

[0002]

2. Description of the Related Art Conventionally, there is a wheelchair as described in Japanese Utility Model Publication No. 4-33850. In this wheelchair, a hydraulic actuator driven by a hydraulic pump is provided between the axle-side member and the seat-side member to adjust the height of the seat manually and to fix the seat at an arbitrary position. Adjustment is conceivable.

[0003]

A first object of the present invention is to make it possible to quickly raise the vehicle height by operating a manual pump.

A second object of the present invention is to make it possible to quickly lower the vehicle height by operating a manual pump.

[0005] A third object of the present invention is to protect a hydraulic circuit from abnormally high pressure.

A fourth object of the present invention is to prevent air from being mixed into hydraulic oil even if the restorer tank is turned over when a wheelchair is folded and mounted on an automobile.

A fifth object of the present invention is to improve the slidability of a free piston which separates an oil chamber and a gas chamber by a reservoir tank, and to prevent the free piston from flowing out of the reservoir tank when the vehicle height is increased. Is to be able to follow well.

[0008] A sixth object of the present invention is to improve the attachment of a component of a hydraulic pump to a wheelchair.

[0009]

According to the first aspect of the present invention, a seat-side member provided with a seat is coupled to an axle-side member provided with a wheel so as to be able to move up and down, so that a space between the axle-side member and the seat-side member is provided. In a vehicle height adjustment device such as a wheelchair, which is provided with a hydraulic actuator driven by a hydraulic pump so that the height of a seat can be adjusted, a plunger in which the hydraulic pump is reciprocally inserted into a pump chamber; A piston attached to the tip of the plunger and partitioning the pump chamber into a plunger-side oil chamber and a piston-side oil chamber; a first oil passage connecting the reservoir oil chamber and the piston-side oil chamber in a reservoir tank; A first check valve provided in a direction to prevent a flow from the piston side oil chamber to the reservoir oil chamber side, a second oil path formed in the piston and communicating the plunger side oil chamber and the piston side oil chamber, 2 oil A second check valve provided to prevent flow from the plunger-side oil chamber to the piston-side oil chamber, a third oil path communicating the plunger-side oil chamber with the hydraulic actuator, and a third oil path connected to the hydraulic actuator side. A third check valve provided in a direction to prevent flow from the pump chamber side to the pump chamber side, a fourth oil path communicating the piston side oil chamber with the hydraulic actuator, and a fourth oil path from the hydraulic actuator side to the pump chamber side. And a fourth check valve provided in a direction for preventing the flow.

According to a second aspect of the present invention, in the first aspect of the present invention, the third and fourth check valves communicate with a third oil passage and a fourth oil passage on a hydraulic actuator side. The flow from the hydraulic actuator side to the reservoir oil chamber side is supplied to the fifth oil path, the sixth oil path that connects the fifth oil path to the hydraulic actuator, and the seventh oil path that connects the fifth oil path to the reservoir oil chamber. And an operation check valve provided in a blocking direction.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the fifth oil passage is connected to an eighth oil passage communicating with a reservoir oil chamber. A blow valve provided in a direction for preventing the flow to the chamber side is provided.

According to a fourth aspect of the present invention, a seat-side member having a seat is coupled to an axle-side member having an axle so as to be able to move up and down, and a hydraulic pump is driven between the axle-side member and the seat-side member. In a vehicle height adjustment device such as a wheelchair that is provided with a hydraulic actuator to be able to adjust the height of the seat,
A reservoir tank for supplying hydraulic oil to the hydraulic pump and discharging hydraulic oil from a hydraulic actuator is divided into an oil chamber and a gas chamber by a movable partition member.

According to a fifth aspect of the present invention, a seat-side member having a seat is coupled to an axle-side member having an axle so as to be able to move up and down, and is driven by a hydraulic pump between the axle-side member and the seat-side member. In a vehicle height adjustment device such as a wheelchair that is provided with a hydraulic actuator to be able to adjust the height of the seat,
Hydraulic oil is supplied to the hydraulic pump, a free piston is slidably provided in a reservoir tank from which hydraulic oil is discharged from a hydraulic actuator, a seal member is provided on the outer periphery of the free piston, and the reservoir tank is provided in an oil chamber and a gas chamber. It is divided and the gas chamber is pressurized.

According to a sixth aspect of the present invention, a seat-side member having a seat is coupled to an axle-side member having an axle so as to be able to move up and down, and is driven by a hydraulic pump between the axle-side member and the seat-side member. In a vehicle height adjustment device such as a wheelchair that is provided with a hydraulic actuator to be able to adjust the height of the seat,
An oil passage for supplying hydraulic oil in a reservoir tank to a hydraulic actuator through a hydraulic pump in a pump housing;
An oil passage for discharging hydraulic oil from the hydraulic actuator to the reservoir tank is formed, the reservoir tank is provided separately from the pump housing, and a supply oil passage and a discharge oil passage in the pump housing are formed inside the reservoir tank via a hydraulic hose. Of the reservoir oil chamber.

[0015]

According to the first aspect of the present invention, the following operations are provided. The hydraulic pump draws the hydraulic oil in the reservoir oil chamber in the reservoir tank into the piston-side oil chamber via the first check valve in the first oil path during the pulling stroke of the plunger by the manual pump operation, and (b) Hydraulic oil sucked in the plunger-side oil chamber sucked in the pushing stroke is discharged to the hydraulic actuator via the third check valve of the third oil passage to increase the vehicle height.

On the other hand, in the hydraulic pump, during the pushing stroke of the plunger by the manual pump operation, (a) a part of the hydraulic oil in the piston side oil chamber sucked in the drawing stroke is passed through the second check valve of the second oil passage. (B) The other part of the hydraulic oil in the piston-side oil chamber is discharged to the hydraulic actuator via the fourth check valve in the fourth oil path, and the vehicle height is increased.

That is, the hydraulic pump supplies hydraulic oil to the hydraulic actuator during both the pulling stroke and the pushing stroke to increase the vehicle height, and the vehicle height can be quickly increased by operating the manual pump.

According to the second aspect of the present invention, the following operations are provided. When the operation of the above manual pump is stopped, the discharge of hydraulic oil by the push stroke and the pull stroke of the hydraulic pump is stopped, and the vehicle height is stopped at an arbitrary vehicle height position, the hydraulic oil of the hydraulic actuator is supplied to the seventh oil passage. Due to the check action of the operation check valve, it cannot be returned to the reservoir oil chamber, but is stopped by the hydraulic actuator to maintain the vehicle height position.

On the other hand, when the non-return action of the operation check valve is released by manual operation, the hydraulic oil of the hydraulic actuator is pressurized by the load acting on the seat, returns to the reservoir oil chamber through the seventh oil path, and The height will be lowered, and the vehicle height can be quickly lowered by operating the manual pump.

According to the third aspect of the present invention, the following operations are provided. Even if the hydraulic actuator reaches the maximum vehicle height up position, if the manual operation of the hydraulic pump is repeated and abnormally high pressure is generated in the hydraulic circuit, or if abnormally high load is applied to the seat and abnormally high pressure is generated in the hydraulic circuit, The blow valve is opened by the set pressure to release an abnormally high pressure higher than the set pressure to the reservoir oil chamber, thereby protecting the hydraulic circuit from the abnormally high pressure.

According to the present invention, there is provided the following operation. Even if the reservoir tank is turned over when the wheelchair is folded and loaded on an automobile, the oil chamber of the reservoir tank is separated from the gas chamber by the movable partition member, thereby preventing air from being mixed into the hydraulic oil. Thus, the use can be started even immediately after the wheelchair horizontally stacked on the car is taken out of the car.

According to the fifth aspect of the present invention, the following operations are provided. A seal member was provided on the outer periphery of a free piston slidably provided in the reservoir tank, and the reservoir tank was partitioned into an oil chamber and a gas chamber. At this time, the pressing force of the gas chamber exerted on the free piston easily overcomes the friction generated between the seal member of the free piston and the inner surface of the tank, and as a result, improves the slidability of the free piston, The free piston can follow the outflow of oil from the reservoir tank during the operation of raising the vehicle height.

According to the sixth aspect of the present invention, the following operations are provided. If the reservoir tank is integrally formed in the pump housing, the size of the pump housing becomes large and a large space for mounting the pump is required in a wheelchair. In the present invention, since the reservoir tank is provided separately from the pump housing, the mounting space for the components of the hydraulic pump can be distributed to various parts of the wheelchair, and the mounting of these components can be improved.

[0024]

FIG. 1 is a perspective view showing a wheelchair, and FIG.
Is a schematic diagram showing a hydraulic pump and a hydraulic actuator, FIG.
FIG. 4 is a schematic view showing attachment of a hydraulic pump to a wheelchair, FIG. 4 is a front view of FIG. 3, FIG. 5 is a plan view of FIG. 3, and FIG. 6 is a hydraulic circuit diagram of the hydraulic pump.

The wheelchair 10 includes a small wheel 1
2. A vehicle height adjusting device 16 that has a hand wheel 13 and a seat 15 on a seat-side member 14 and that can adjust the height of the seat 15 by connecting the seat-side member 14 to the axle-side member 11 so as to be able to move up and down. Have.

The axle-side member 11 is provided with a left axle-side frame 17.
A and the right axle-side frame 17B are connected by the front connection link 18 and the rear connection link 19, respectively, and the left and right axle-side frames 17A, 17B are width-changed by bending the front connection link 18 by a folding operation unit (not shown). It is possible to fold it up. Left and right axle side frames 17A, 1
Each of the wheels 7B has an axle 20 on which a hand wheel 13 is supported.

The seat-side member 14 includes a left seat-side frame 21.
A and the right seat-side frame 21B are respectively coupled to the guide posts 23A, 23B of the left and right axle-side frames 17A, 17B via their lifting guides 22A, 22B so as to be able to move up and down. Accordingly, when the left and right axle-side frames 17A, 17B of the axle-side member 11 are narrowed and folded, the left and right seat-side frames 21A, 21A,
21B is also folded at the same time. The left and right seat-side frames 21A and 21B are provided with left and right armrests 24 and footrests 25. The left and right seat side frames 21
A and 21B are provided with left and right brake levers 26, so that the left and right brake members 27 provided on the left and right axle side frames 17A and 17B for the left and right hand wheel 13 can be manually operated.

However, the vehicle height adjusting device 16 includes the left and right axle-side frames 17A, 17B of the axle-side member 11 and the left and right seat-side frames 21A, 21 of the seat-side member 14.
B between the left and right hydraulic actuators 30
(30A, 30B) and the seat-side member 1
The hydraulic pump 40 is disposed under the armrest 24 on one of the left and right seat-side frames 21A and 21B constituting the seat 4, and the hydraulic pump 40 expands and contracts the left and right hydraulic actuators 30A and 30B to increase the height of the seat 15. Adjustable.

One end of a wire 101 is fixed to the lower end of the elevating guide 22A of the left seat side frame 21A, and the wire 101 is connected to the left axle side frame 17A, the rear connecting link 19, and the right axle side frame 17B. It is wound around the provided pulleys 101A, 101B, 101C, and the other end is connected to the upper end of the lifting guide 22B of the right seat side frame 21B. On the other hand, one end of a wire 102 is fixed to the lower end of the lifting guide 22B of the right seat side frame 21B, and the wire 102 is a pulley provided on each of the right axle side frame 17B, the rear connection link 19, and the left axle side frame 17A. It is wound around 102A (not shown), 102B and 102C, and the other end is connected to the upper end of the lifting guide 22A of the left seat side frame 21A. Thus, the vertical movements of the left and right seat side frames 21A, 21B are evenly and synchronously synchronized with each other.

Hereinafter, the hydraulic actuator 30 (30A,
30B) and the hydraulic pump 40 will be described in detail. (Hydraulic actuator 30) (FIG. 2) Hydraulic actuator 30 (30A and 30B have the same configuration)
As shown in FIG. 2, the cylinder 31 is connected to one of the axle-side frame 17A (or 17B) of the axle-side member 11 and the seat-side frame 21A (or 21B) of the seat-side member 14, and the other is connected to the other. And a piston rod 32 provided at the insertion end of the piston rod 32 into the cylinder 31.
Is partitioned into a rod-side chamber 34 and a piston-side chamber 35. At this time, the hydraulic actuator 30 is a single-acting type, and the pressure-resistant hydraulic hose 8 is provided only at one end of the cylinder 31.
1 and the piston 33 has a rod side chamber 3
4 and a communication hole 33 </ b> A that communicates with the piston side chamber 35. The hydraulic hose 81 is connected to the cylinder 31 via a joint 81A. This allows the hydraulic actuator 30 to (a) extend the piston rod 32 by a length corresponding to the amount of oil supplied to the cylinder 31 and generate hydraulic pressure corresponding to the integral of the piston rod cross section acting on the piston 33 to load And (b)
The piston rod 32 is contracted by a length corresponding to the amount of oil discharged from the cylinder 31, and a hydraulic pressure corresponding to the integral area of the piston rod acting on the piston 33 is generated to support the load.

(Hydraulic Pump 40) (FIGS. 2 to 6) The hydraulic pump 40 has a pump housing 41 and a reservoir tank 42. In the hydraulic pump 40, a pump chamber 43 having a hole shape is formed in a pump housing 41, a plunger 44 is reciprocally inserted into the pump chamber 43, and the pump chamber 43 is moved to the plunger side by a piston 45 attached to a tip of the plunger 44. An oil chamber 46 and a piston-side oil chamber 47 are defined. In addition, a vehicle height up lever 49 that is swingably supported by a support shaft 48 provided on the pump housing 41 is connected to a base end of the plunger 44 outside the pump housing 41. The pushing process of pushing the plunger 44 into the pump chamber 43 and the pulling process of pulling it out are repeated by the manual swing operation of the vehicle height up lever 49.

In the hydraulic pump 40, a free piston 51 as a movable partition member is slidably provided in a reservoir tank 42, and a seal member (O-ring) 52 is provided on the outer periphery of the free piston 51 so that the reservoir tank 42 is filled with a reservoir oil chamber. 5
3 and a gas chamber 54, and the gas chamber 54 is pressurized.
55 is a pressurized gas filling valve.

The hydraulic pump 40 is connected to a reservoir oil chamber 53 of the reservoir tank 42 and a first oil chamber 47 on the piston side.
An oil passage 61 is provided in the pump housing 41, and a first check valve 71 is provided in the first oil passage 61 so as to prevent a flow from the piston side oil chamber 47 to the reservoir oil chamber 53. The suction pressure generated in the piston-side oil chamber 47 during the stroke of the plunger 44 by the vehicle height up lever 49 opens the first check valve 71, and allows the hydraulic oil in the reservoir oil chamber 53 to be sucked into the piston-side oil chamber 47.

The hydraulic pump 40 includes a plunger-side oil chamber 46.
A second oil passage 62 communicating between the piston 45 and the piston-side oil chamber 47 is formed in the piston 45, and a flow from the plunger-side oil chamber 46 to the piston-side oil chamber 47 is blocked in the second oil passage 62. A second check valve 72 is provided.
The suction pressure generated in the plunger-side oil chamber 46 during the pushing stroke of the plunger 44 by the vehicle height up lever 49 opens the second check valve 72 and operates the piston-side oil chamber 47 that has been sucked into the piston-side oil chamber 47 during the drawing stroke. A part of the oil can be sucked into the plunger-side oil chamber 46.

The hydraulic pump 40 includes a plunger side oil chamber 46.
And a third oil passage 63 communicating the cylinder 31 of the hydraulic actuator 30 with the pump housing 41.
The third oil passage 63 is provided with a third check valve 73 provided in a direction for preventing a flow from the cylinder 31 of the hydraulic actuator 30 to the pump chamber 43. The plunger-side oil chamber 4 that has been sucked into the plunger-side oil chamber 46 by the pushing stroke during the pulling stroke of the plunger 44 by the vehicle height up lever 49.
The hydraulic oil in 6 is discharged to the cylinder 31 of the hydraulic actuator 30 via the third check valve 73 of the third oil passage 63 to extend the piston rod 32 and increase the vehicle height.

The hydraulic pump 40 is connected to the fourth oil chamber 47 which communicates the piston side oil chamber 47 with the cylinder 31 of the hydraulic actuator 30.
An oil passage 64 is provided in the pump housing 41, and the fourth oil passage 64 is connected to the cylinder 3 of the hydraulic actuator 30.
A fourth check valve 74 is provided in a direction for preventing the flow from 1 to the pump chamber 43. During the pushing stroke of the plunger 44 by the vehicle height up lever 49, the operating oil in the piston side oil chamber 47 that has been sucked into the piston side oil chamber 47 during the pulling stroke is hydraulically transmitted through the fourth check valve 74 of the fourth oil passage 64. It is discharged to the cylinder 31 of the actuator 30 to extend the piston rod 32, thereby increasing the vehicle height.

The hydraulic pump 40 is connected to the hydraulic actuator 30 of the third check valve 73 and the fourth check valve 74 described above.
On the side, a fifth oil passage 65 communicating with the third oil passage 63 and the fourth oil passage 64 is provided in the pump housing 41, and the fifth oil passage 65 is connected to the cylinder of the hydraulic actuator 30 via the hydraulic hose 81 described above. Sixth oil passage 6 communicating with 31
6 is provided on the pump housing 41. Hydraulic hose 8
1 is connected to the sixth oil passage 66 via a joint 81B.

A seventh oil passage 67 is provided in the pump housing 41 for communicating the fifth oil passage 65 with the reservoir oil chamber 53 of the reservoir tank 42. The seventh oil passage 67 is connected to the cylinder 31 of the hydraulic actuator 30. From reservoir oil chamber 5
3 is provided with an operation check valve 75 provided in a direction for preventing the flow to 3. The operation check valve 75 is pushed by a manual swing operation of a vehicle height down lever 77 swingably supported on a support shaft 76 provided in the pump housing 41.
The valve is opened via the valve 8 so that the check operation from the cylinder 31 of the hydraulic actuator 30 to the reservoir oil chamber 53 can be released. That is, due to the check action of the operation check valve 75, the hydraulic oil of the cylinder 31 of the hydraulic actuator 30 is retained on the hydraulic actuator 30 side, and the vehicle height position is maintained. In addition, when the check operation of the operation check valve 75 is released by the vehicle height down lever 77, the hydraulic oil of the cylinder 31 of the hydraulic actuator 30 is pressurized by the load of the seat 15 and is moved from the seventh oil passage 67 to the reservoir oil chamber 53. Return and the vehicle height goes down.

The hydraulic pump 40 is connected to a reservoir oil chamber 53 of the reservoir tank 42 through the fifth oil passage 65 described above.
An oil passage 68 is provided in the pump housing 41, and the eighth oil passage 68 is connected to the reservoir oil chamber 5 from the hydraulic actuator 30 side.
3 is provided with a blow valve 79 for blocking the flow to the third side. The blow valve 79 opens when the pressure on the hydraulic actuator 30 side rises to a predetermined set pressure or higher.

As described above, the hydraulic pump 40 includes the first oil passage 61, the third oil passage 63, the fourth oil passage 64, the fifth oil passage 65, the sixth oil passage 66, the seventh oil passage 67, and the eighth oil passage 67. An oil passage 68 is provided in the pump housing 41, the reservoir tank 42 is provided separately from the pump housing 41, and the first oil passage 61, the seventh oil passage 67, and the eighth oil passage 68 provided in the pump housing 41 are connected to a joint 82.
A, and the pressure-resistant hydraulic hose 82 connected to the joint 82A is connected to the reservoir oil chamber 53 of the reservoir tank 42 by the joint 82B.

As shown in FIG. 4, the pump housing 41 is connected to the seat-side frame 21 via a mounting spacer 111.
A and 21B are bolted to the side plate 112. Further, the reservoir tank 42 is tightly fixed to the side plate 112 by a belt-like mounting band 113. In addition, the reservoir tank 42
Is separated from the pump housing 41 to avoid interference with spokes of the wheels 13 and the like.

Accordingly, the vehicle height adjusting device 16 operates as follows. (1) Vehicle Height Up Operation The hydraulic oil in the plunger side oil chamber 46 is discharged to the cylinder 31 of the hydraulic actuator 30 via the third check valve 73 of the third oil passage 63 in the stroke of the plunger 44 being moved by the vehicle height up lever 49. Then, the piston rod 32 is extended to increase the vehicle height. Also, in the pushing stroke of the plunger 44 by the vehicle height up lever 49, the operating oil in the piston side oil chamber 47 is discharged to the cylinder 31 of the hydraulic actuator 30 via the fourth check valve 74 of the fourth oil passage 64, and the piston rod 32 To increase the vehicle height.

After the seat 15 is set to a desired height by the above-described vehicle height increasing operation of the vehicle height increasing lever 49, the operating oil of the cylinder 31 of the hydraulic actuator 30 is changed to the seventh oil.
The operation check valve 75 of the oil passage 67 is retained on the cylinder 31 by the check action, and maintains the vehicle height position.

(2) Vehicle Height Down Operation When the check operation of the operation check valve 75 is released by the vehicle height down lever 77, the hydraulic oil of the cylinder 31 of the hydraulic actuator 30 is pressurized by the load acting on the seat 15. Then, the vehicle returns to the reservoir oil chamber 53 of the reservoir tank 42 through the seventh oil passage 67, and the vehicle height is lowered until the release of the check operation of the operation check valve 75 by the vehicle height down lever 77 is stopped.

According to the present embodiment, the following operations are provided. The hydraulic pump 40 supplies (a) the operating oil in the reservoir oil chamber 53 in the reservoir tank 42 with the first check valve 71 in the first oil passage 61 during the pulling stroke of the plunger 44 by the manual pump operation.
(B) the hydraulic oil in the plunger-side oil chamber 46 sucked in the pushing stroke is discharged to the hydraulic actuator 30 through the third check valve 73 of the third oil passage 63. Raise the vehicle height.

On the other hand, in the hydraulic pump 40, during the pushing stroke of the plunger 44 by the manual pump operation, (a) a part of the working oil in the piston side oil chamber 47 sucked in the drawing stroke is supplied to the second oil passage 6.
And (b) another part of the hydraulic oil in the piston-side oil chamber 47 is supplied to the hydraulic actuator via the fourth check valve 74 in the fourth oil passage 64. Discharge to 30 to increase vehicle height.

That is, the hydraulic pump 40 supplies the hydraulic oil to the hydraulic actuator 30 in both the pulling stroke and the pushing stroke to increase the vehicle height. The vehicle height can be quickly increased by operating the manual pump.

When the operation of the above manual pump is stopped, the discharge of hydraulic oil by the pushing stroke and the pulling stroke of the hydraulic pump 40 is stopped, and the vehicle height is stopped at an arbitrary vehicle height position, the hydraulic oil of the hydraulic actuator 30 becomes Due to the check action of the operation check valve 75 in the seventh oil passage 67, the operation check valve 75 cannot be returned to the reservoir oil chamber 53 and is retained by the hydraulic actuator 30 to maintain the vehicle height position.

On the other hand, the operation check valve 7 is manually operated.
5 is released, the hydraulic oil of the hydraulic actuator 30 is pressurized by the load acting on the seat 15, and
Returning to the reservoir oil chamber 53 through the oil passage 67, the vehicle height is reduced, and the vehicle height can be quickly reduced by operating the manual pump.

Even if the hydraulic actuator 30 reaches the maximum vehicle height increasing position, the manual operation of the hydraulic pump 40 is repeated to generate an abnormally high pressure in the hydraulic circuit, or the seat 15 may not be operated.
When an abnormally large load acts on the hydraulic circuit to generate an abnormally high pressure, the blow valve 79 opens by the set pressure and releases the abnormally high pressure that is higher than the set pressure to the reservoir oil chamber 53. Can be protected.

Even if the reservoir tank 42 is turned over when the wheelchair 10 is folded and loaded on an automobile, the oil chamber 53 of the reservoir tank 42 is separated from the gas chamber 54 by a free piston 51 as a movable partition member. It is possible to prevent air from entering the inside. As a result, the use can be started even immediately after the wheelchair 15 horizontally stacked on the car is taken out of the car.

A seal member 52 is provided on the outer periphery of a free piston 51 slidably provided in the reservoir tank 42, and the reservoir tank 42 is divided into an oil chamber 53 and a gas chamber 54. At this time, the pressure of the gas chamber 54 exerted on the free piston 51 easily overcomes the friction generated between the seal member 52 of the free piston 51 and the inner surface of the tank 42, and as a result, the free piston 51
And the free piston 51 can follow the outflow of oil from the reservoir tank 42 during the operation of increasing the vehicle height.

When the reservoir tank 42 is integrally formed in the pump housing 41, the pump housing 41 becomes large, and a large space for mounting the pump is required in a wheelchair. In the present invention, since the reservoir tank 42 is provided separately from the pump housing 41, the mounting space for the components of the hydraulic pump 40 can be distributed to various parts of the wheelchair, and the mounting of these components can be improved.

Note that the wheelchair 10 includes an axle-side member 11 and a seat-side member 14 which are connected to left and right axle-side frames 17A,
7B and left and right seat-side frames 21A and 21B, and the left and right axle-side frames 17A, 1
7B and left and right seat side frames 21A of the seat side member 14,
21B and the right and left hydraulic actuators 3
0A, 30B, and the hydraulic pump 40 and the cylinder 31 of each actuator 30A, 30B are connected by a hydraulic hose 81, so that the left and right hydraulic actuators 30A,
The wheelchair 10 can be folded while having 30B.

The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration of the present invention is not limited to this embodiment, and the design can be changed without departing from the scope of the present invention. The present invention is also included in the present invention. For example, the movable partition member provided in the reservoir tank of the present invention and separating the oil chamber and the gas chamber is not limited to a free piston, but may be a diaphragm or the like.

[0056]

As described above, according to the present invention, the vehicle height can be quickly increased by operating the manual pump.

Further, according to the present invention, the vehicle height can be quickly reduced by operating the manual pump.

Further, according to the present invention, the hydraulic circuit can be protected from abnormally high pressure.

Further, according to the present invention, it is possible to prevent air from being mixed into the hydraulic oil even if the restorer tank is turned over when the wheelchair is folded and loaded on a car.

Further, according to the present invention, the slidability of the free piston that separates the oil chamber and the gas chamber from the reservoir tank is improved, and the free piston is used to allow oil to flow out of the reservoir tank when the vehicle height is increased. You can follow well.

According to the present invention, it is possible to improve the attachment of the components of the hydraulic pump to a wheelchair.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a wheelchair.

FIG. 2 is a schematic diagram showing a hydraulic pump and a hydraulic actuator.

FIG. 3 is a schematic diagram showing attachment of a hydraulic pump to a wheelchair.

FIG. 4 is a front view of FIG. 3;

FIG. 5 is a plan view of FIG. 3;

FIG. 6 is a hydraulic circuit diagram of a hydraulic pump.

[Explanation of symbols]

 Reference Signs List 10 wheelchair 11 axle side member 14 seat side member 15 seat 16 vehicle height adjusting device 30, 30A, 30B hydraulic actuator 40 hydraulic pump 41 pump housing 42 reservoir tank 43 pump chamber 44 plunger 45 piston 46 plunger side oil chamber 47 piston side oil chamber 49 Vehicle height up lever 51 Free piston 52 Seal member 53 Reservoir oil chamber 54 Gas chamber 61 First oil path 62 Second oil path 63 Third oil path 64 Fourth oil path 65 Fifth oil path 66 Sixth oil path 67th 7 oil passage 68 eighth oil passage 71 first check valve 72 second check valve 73 third check valve 74 fourth check valve 75 operation check valve 77 vehicle height down lever 79 blow valves 81, 82 hydraulic hose

Claims (6)

[Claims] An axle-side member having wheels is coupled to a seat-side member having a seat so as to be able to move up and down, and a hydraulic actuator driven by a hydraulic pump is provided between the axle-side member and the seat-side member. In a vehicle height adjusting device such as a wheelchair capable of adjusting the height of a plunger, the hydraulic pump is reciprocally inserted into a pump chamber, and is attached to a tip of the plunger. A first oil passage connecting the reservoir oil chamber and the piston oil chamber in the reservoir tank, and a flow from the piston oil chamber to the reservoir oil chamber in the first oil passage. A first check valve provided in a direction in which the piston-side oil chamber communicates with a plunger-side oil chamber formed in the piston and a piston-side oil chamber. A second check valve provided in a direction to block the flow of the third communicating the plunger-side oil chamber and the hydraulic actuator
An oil passage, a third check valve provided in the third oil passage in a direction for preventing flow from the hydraulic actuator side to the pump chamber side, a fourth oil passage communicating the piston side oil chamber with the hydraulic actuator, A vehicle height adjusting device, such as a wheelchair, comprising: a fourth check valve provided in an oil passage in a direction for preventing a flow from a hydraulic actuator side to a pump chamber side. 2. A fifth oil passage communicating with the third oil passage and the fourth oil passage on the hydraulic actuator side of the third and fourth check valves, and a sixth oil communicating the fifth oil passage with the hydraulic actuator. A passage, and an operation check valve provided in a seventh oil passage communicating the fifth oil passage and the reservoir oil chamber in a direction for preventing a flow from the hydraulic actuator side to the reservoir oil chamber side. A vehicle height adjusting device such as the wheelchair according to 1. 3. A blow valve provided in an eighth oil passage connecting the fifth oil passage to a reservoir oil chamber in a direction for preventing a flow from a hydraulic actuator side to a reservoir oil chamber side. A vehicle height adjusting device such as a wheelchair according to claim 1. 4. An axle-side member having an axle is coupled to a seat-side member having a seat so as to be able to move up and down, and a hydraulic actuator driven by a hydraulic pump is provided between the axle-side member and the seat-side member. In a vehicle height adjustment device such as a wheelchair, the height of which can be adjusted, a hydraulic oil is supplied to the hydraulic pump, and a reservoir tank from which the hydraulic oil is discharged from the hydraulic actuator is moved to an oil chamber and a gas by a movable partition member. A vehicle height adjustment device such as a wheelchair, which is divided into rooms. 5. An axle-side member provided with an axle, a seat-side member provided with a seat is coupled to the seat member so as to be able to move up and down, and a hydraulic actuator driven by a hydraulic pump is provided between the axle-side member and the seat-side member. In a vehicle height adjusting device such as a wheelchair that can adjust the height of the hydraulic pump, hydraulic oil is supplied to the hydraulic pump, and a free piston is slidably provided in a reservoir tank from which hydraulic oil is discharged from a hydraulic actuator, A height adjustment device for a wheelchair or the like, wherein a seal member is provided on an outer periphery of a free piston, a reservoir tank is divided into an oil chamber and a gas chamber, and the gas chamber is pressurized. 6. An axle-side member provided with an axle, a seat-side member provided with a seat is coupled to be movable up and down, and a hydraulic actuator driven by a hydraulic pump is provided between the axle-side member and the seat-side member. In a vehicle height adjusting device such as a wheelchair capable of adjusting the height of a wheelchair, an oil passage for supplying hydraulic oil in a reservoir tank to a hydraulic actuator through a hydraulic pump in a pump housing, and a hydraulic oil from the hydraulic actuator to a reservoir. An oil passage for discharging to the tank was formed, the reservoir tank was provided separately from the pump housing, and a supply oil passage and a discharge oil passage in the pump housing were connected to a reservoir oil chamber in the reservoir tank via a hydraulic hose. A vehicle height adjusting device such as a wheelchair.