JPH04361749A - Electric wheelchair - Google Patents

Abstract

PURPOSE:To provide a safe electric wheelchair which can enhance the degree of freedom in going up and down the stairs and which does not make its user feel uneasy. CONSTITUTION:The caterpillar frame 3 of a caterpillar mechanism 4 is axially supported at the front portion of a main body frame 2 in such a manner as freely oscillating and is supported by a cylinder device 27 from the rear portion of the main body frame 2. Direction changing wheels 19 which are made to project downward by the caterpillar mechanism when the cylinder device is made to expand are provided at the rear portion of the main body frame and pressure sensors 10, 11, 12, 19a are provided for detecting loads applied to driving wheels 4, driven wheels 4d, 4c and the direction changing wheels 19, respectively, and a chair 21 supported on the main body frame 2 is axially supported in such a way as freely oscillating and is provided with a horizontal detecting device 29 keeping the chair horizontal and with oscillation control means 24, 25, 36, 38.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric wheelchair, and more particularly to an improvement in an electric wheelchair that can ascend and descend stairs using a caterpillar mechanism.

0002

BACKGROUND OF THE INVENTION Conventionally, this type of electric wheelchair has been disclosed in, for example, Japanese Patent Laid-Open Nos. 59-144455 and 1-17155.
This method has been proposed in Japanese Patent No. 0 and Japanese Patent Application Laid-open No. 1-171551. The electric wheelchair proposed in the above-mentioned Japanese Patent Application Laid-Open No. 59-144455 has a chassis frame and an upright support column, the lower end of which is pivoted on the frame and extends in the front-rear direction with respect to the frame. an upright support column that is swingable; a cargo platform attached to the upper end of the column; and wheels attached to the frame and providing a first wheelbase for the vehicle; Some include a plurality of wheels driven by a motor, and two retaining plates each located on the side of said frame, each retaining plate retaining a caterpillar belt driven by a motor, and two retaining plates each retaining a caterpillar belt driven by a motor. a retaining plate adapted to form a second wheel base for the vehicle; and causing said retaining plate to undergo a coincident translational movement, thereby bringing one of said wheel bases into contact with a floor surface and the other away from said retaining plate. mounting means,
a link mechanism connecting the support column and the attachment means, the vertical axis passing through the center of gravity of the combined load of the luggage platform and its luggage into the wheelbase of the one in contact with the floor surface; and a link mechanism that changes the angular arrangement of the column so as to direct the column.

Further, the electric wheelchair proposed in the above-mentioned Japanese Patent Application Laid-open No. 1-171550 has a front wheel mechanism fixed to the front of the main body frame, and a front wheel mechanism that extends diagonally rearward from the position of the front wheel mechanism and is driven by a power source. A caterpillar mechanism that moves the rear wheel mechanism behind the main body frame, a rear wheel sliding mechanism that allows the rear wheel mechanism to slide freely relative to the main body frame, and a rear wheel mechanism that moves the rear wheel from the ground surface of the caterpillar when going up and down stairs. It has a rear wheel telescoping mechanism for moving the main frame upward and a tilting mechanism for tilting the main body frame rearward.

Furthermore, the electric wheelchair proposed in the above-mentioned Japanese Patent Application Laid-Open No. 1-171551 has a front wheel mechanism provided on the main body frame, a caterpillar mechanism extending diagonally rearward from the position of the front wheel mechanism and driven by a power source. It includes a rear wheel telescoping mechanism provided at the rear of the main body frame, and a rear wheel sliding mechanism that enables the rear wheel telescoping mechanism to move back and forth, and the rear wheel telescoping mechanism and the rear wheel sliding mechanism include a rear wheel telescoping mechanism. A plurality of sensors are arranged to detect movement positions, and signals from the sensors control the power source of the rear wheel telescoping mechanism and the rear wheel sliding mechanism.

[0005]

[Problems to be Solved by the Invention] By the way, these electric wheelchairs are configured so that the user sitting in the electric wheelchair climbs the stairs facing backwards. Having to climb the stairs while turning around was inconvenient and caused anxiety.

[0006]Furthermore, when going down stairs, the posture of the electric wheelchair becomes unstable at the exit, making the user feel uneasy.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to provide a safe electric wheelchair that can improve the degree of freedom of going up and down stairs and does not make the user feel uneasy.

[0008]

[Means for Solving the Problems] According to the electric wheelchair according to the present invention, the electric wheelchair is equipped with caterpillar mechanisms on both sides of the main body frame on which the chair is supported.
A caterpillar frame of the caterpillar mechanism is swingably supported on the front part of the main body frame, and the caterpillar frame is supported from the rear part of the main body frame by a cylinder device, and the cylinder device is retracted in the rear part of the main body frame. a chair supported on the main body frame, comprising a wheel for changing direction that projects downward from the caterpillar mechanism when the caterpillar mechanism This is achieved by pivoting the chair so that it can swing freely, and equipping the chair with a horizontal detection device and swing control means for maintaining the chair horizontally.

[0009]

[Operation] According to the above structure, the caterpillar frame of the caterpillar mechanism is swingably supported on the front part of the main body frame, and the caterpillar frame is supported by the cylinder device from the rear of the main body frame, so that the cylinder device can By expanding and contracting, the caterpillar mechanism provided on the caterpillar frame can be swung relative to the main body frame.

[0010] Also, a wheel for changing direction is provided at the rear of the main body frame, and when the cylinder device is retracted and the rear part of the caterpillar mechanism is raised, this wheel for changing direction projects downward from the caterpillar mechanism. Stairs can be safely ascended and descended by using a caterpillar mechanism and wheels for changing direction. Not only can the direction be changed by the caterpillar mechanism, but also the direction can be changed by the above-mentioned direction change wheels, which makes it particularly easy to make sudden changes and improve the degree of freedom of going up and down stairs.

Furthermore, since the drive wheel, follower wheel, and direction change wheel of the caterpillar mechanism are equipped with pressure sensors that detect the load applied to each, the information detected by each pressure sensor is used to safely ascend and descend stairs. can do.

[0012]The chair supported on the main frame is swingably supported, and the chair is provided with a horizontal detection device and swing control means for maintaining the chair horizontally. By using the detection signal from the detection device, the swing control means always maintains the horizontal position of the chair even when going up and down stairs.
To prevent the user from feeling uneasy and to ensure safe driving.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the electric wheelchair according to the present invention will be described in detail below with reference to the drawings. The electric wheelchair according to the present invention is constructed as shown in FIGS. 1 to 4. As shown in the figure, the front part of the main body frame 2 of the electric wheelchair 1 has a caterpillar frame support part 2a bent downward.
is formed. This caterpillar frame support part 2a
A pair of caterpillar frames 3 bent upward in a U-shape are pivotally supported on the left and right sides of the frame, and a large follower wheel 4a of the caterpillar mechanism 4 is pivotally supported on these shafts. ing. A small follower wheel 4b is pivotally supported at the tip of the upwardly inclined front part of the caterpillar frame 3, and a large drive wheel 4c is pivotally supported at the rear end of each caterpillar frame 3. . A sprocket 5 is attached to the drive shaft of each drive wheel 4c. A drive belt 8 is stretched between the sprocket 5 and a sprocket 7 attached to the drive shafts of left and right running motors 6a, 6b supported at the front part of the caterpillar frame 3, respectively. The wheels 4c are driven by running motors 6a and 6b via a drive belt 8. Further, a plurality of intermediate follower wheels 4d, 4e, 4f, and 4g are pivotally supported between the drive wheel 4c and the large follower wheel 4a. These driving wheels 4c and following wheels 4a, 4
An endless caterpillar belt 9 is stretched over the wheels b, 4d, 4e, 4f, and 4g, and each of the driven wheels 4a, 4b, 4d, and 4e, 4f, and 4g are driven to rotate.

[0014] Also, the following wheels 4d, 4e and the driving wheel 4c
Pressure sensors 10, 11, and 12 are attached to each bearing, respectively, to detect when a predetermined pressure is applied. As shown in FIG. 5, each pressure sensor 10, 11, 12 is supported by a support piece 13 that pivotally supports the driven wheels 4d, 4e or the driving wheel 4c at one end, and the other end of the support piece 13. a sensor body 15 having a groove 15a for guiding the rotation shaft 14; a spring 16 for biasing the support piece 13 downward from the sensor body 15; ON/O by sliding inside
It is composed of a pressure switch 17 that is turned off.

Furthermore, a direction changing motor 18 is supported at the center of the rear part of the main body frame 2, and a pair of direction changing wheels 19 are mounted on the drive shaft of this direction changing motor 18. installed. A power battery 20 is provided on the rear side of the direction change motor 18. In addition, the direction changing wheel 19 is
A pressure sensor 19a similar to the pressure sensors 10, 11, and 12 described above is provided on the axle.

[0016] At the front part of the main body frame 2,
A chair 21 is pivotably supported. As shown in FIG. 6, one of the shafts 22 is equipped with a swing motor 24 via a speed reducer 23, and the other shaft 22 is equipped with a first potentiometer 25. A control lever 26 for controlling the movement of the electric wheelchair 1 is provided in an upright position on the right front side of the chair 21 at a position where the user can easily operate it.

A caterpillar rocking power cylinder 27 is attached to the rear of the chair 21, and the caterpillar frame 3 is attached to its rod end 27a via a rotation shaft 28. By shortening the power cylinder 27 for swinging the caterpillar, the large follower wheel 4
The rear part of the caterpillar frame 3 rises around point a.

A horizontal detection device 29 as shown in FIGS. 6 to 8 is mounted on the main body frame 2. This horizontal detection device 29 includes a box 31 containing a liquid 30 such as oil, a rotating shaft 32 that is rotatably inserted into the upper side wall of the box 31, and a rotating shaft 32 that connects the box 30 to the box 30.
A plate piece 33 hanging down inside, a weight 34 attached to the lower end of the plate piece 33, and a coupling 35 to the rotating shaft 32.
and a second potentiometer 36 for detecting the swing angle of the rotating shaft 32, which is attached through the rotary shaft 32. The second potentiometer 36 is attached to a support wall 37 that is formed integrally with the box body 31 at a predetermined distance from the box body 31 . This second potentiometer 36 is connected to a controller 38 provided on the main body frame 2, and is configured to receive a swing angle detection signal. The controller 38 also operates a swing motor 2 attached to the swing shaft 22 of the chair 21.
4 and the first potentiometer 25 . When the main body frame 2 tilts either forward or backward, the box 31 of the horizontal detection device 29 also tilts, but since the plate 33 is maintained vertically by the weight 34, the axis of the second potentiometer 36 is It is rotated by the amount of oscillation of the attached rotating shaft 32, and the oscillation angle can be detected by the change in resistance value. Then, the detection signal is input to the controller 38, and the controller 3
8, the input signal is compared with the input signal from the first potentiometer 25, and the controller 38 rotates the rocking motor 24 of the chair 21, so that the chair 21 remains horizontal even if the main body frame 2 is tilted forward or backward. It has become. Incidentally, the vibration and acceleration while the electric wheelchair 1 is running are caused by the liquid 30 and the plate piece 33 inside the box body 31 of the horizontal detection device 29.
It is absorbed by the resistance.

Next, the operation of the above embodiment will be described. When the electric wheelchair 1 of this embodiment runs on flat ground, the power cylinder 27 for swinging the caterpillar is retracted, only the trailing wheel 4a is in contact with the ground, and the rear part of the caterpillar mechanism 4 is raised, and the rear part is in the above-mentioned direction. The switching wheel 19 is in contact with the ground. The user of the electric wheelchair 1 can operate the direction change motor 18 and change the direction of the direction change wheel 19 by moving the control lever 26 left and right.

Further, when traveling only by the caterpillar mechanism 4, the control lever 26 is operated.
Direction change is performed by giving a difference in the rotation speeds of the left and right travel motors 6a, 6b.

Furthermore, when climbing stairs with the electric wheelchair 1 of this embodiment, the control lever 26 is operated before the stairs 39 to switch to running using the caterpillar mechanism 4 (see FIG. 9). In the figure, A), ascending the stairs 39 using only the caterpillar mechanism 4 (B, C in the figure)
. When the user reaches the top of the stairs 39 and the pressure sensor 11 detects this, the electric wheelchair 1 temporarily stops (D in the figure). In the paused state, the power cylinder 27 for swinging the caterpillar is retracted, the rear part of the caterpillar mechanism 4 is raised, and the direction changing wheel 19 is brought into contact with the ground (see E in the figure).
), continue forward (F in the figure). Next, when the direction changing wheel 19 comes into contact with the upper vertical wall of the stairs 39, the pressure sensor 19a detects this and pauses again, the caterpillar swinging power cylinder 27 is extended, and the caterpillar mechanism 4 is activated. It descends (G in the figure), changes to running by the caterpillar mechanism 4, and moves forward. After that, when the ground is reached, the power cylinder 27 for swinging the caterpillar is retracted, the rear part of the caterpillar mechanism 4 is raised, the direction changing wheels 19 are brought into contact with the ground, and the vehicle is switched to running on a flat ground (see H in the figure).
).

[0022] When the electric wheelchair 1 of this embodiment goes down the stairs, it goes down the stairs 39 as shown in FIG.
In front of , operate the control lever 26 to switch to running by the caterpillar mechanism 4 (I in the figure). If the wheelchair continues as it is, the front part of the electric wheelchair 1 will protrude from the level ground, and a load will be applied to the pressure sensor 10. The pressure sensor 10
When it detects this, it pauses (J in the figure). In the temporarily stopped state, the caterpillar swinging power cylinder 27
is shortened, the rear part of the caterpillar mechanism 4 rises, the direction changing wheels 19 touch the ground, and the inclination of the stairs 39 and the inclination of the caterpillar mechanism 4 become approximately the same (K in the figure). Moving forward again, the caterpillar swinging power cylinder 27 is extended while going down the stairs 39, and the caterpillar mechanism 4 is lowered (L in the figure) until it descends to the bottom of the stairs 39 and the pressure sensor 12 detects this. Pause (M in the diagram). Then, the power cylinder 27 for swinging the caterpillar is retracted, the caterpillar mechanism 4 is raised (N in the figure), the direction changing wheel 19 is brought into contact with the ground, and the vehicle moves to flat ground running (O in the figure).
.

As described above, in this embodiment, the chair 21 of the electric wheelchair 1 moves up and down the stairs 39 with the chair 21 facing forward, so that the user does not feel uneasy. Further, by using the caterpillar mechanism 4 and the direction change wheels 19 in combination, the stairs 39 can be safely ascended and descended, and the degree of freedom in ascending and descending the stairs can be improved. Furthermore, each pressure sensor 1
Based on the information detected by 0, 11, 12, and 19a, it is possible to safely ascend and descend the stairs 39.

In this way, even if the electric wheelchair 1 of this embodiment tilts back and forth when going up and down the stairs 39, the main body frame 2
The chair 21 provided above always maintains a horizontal position. This means that when the main body frame 2 and the chair 21 are in a horizontal state, the first and second potentiometers 25
, 36 are set to the same value, and when the body frame 2 is tilted and the resistance value of the second potentiometer 36 changes, the detection signal is sent to the controller 38.
The controller 38 compares the detection signal input from the first potentiometer 25 with the detection signal from the second potentiometer 36, and controls the swing motor so that these resistance values are always the same. 24, the chair 21 is maintained horizontally. In this way, the first and second potentiometers 25
, 36 causes the controller 38 to operate the swing motor 24, so that the chair 21 can be moved even when going up and down stairs.
By always maintaining the level of the vehicle, the user does not feel uneasy and safe driving can be ensured.

Furthermore, in this embodiment, two types of direction changing mechanisms, the caterpillar mechanism 4 and the direction changing wheels 19, are employed to improve the degree of freedom of travel. The reason for changing the direction using the direction changing wheels 19 is that if the direction is changed by giving a difference in the rotational speed of the left and right traveling motors 6a and 6b of the caterpillar mechanism 4, it is difficult to make a sudden change, especially on flat ground. This is because the need is great. In addition, changing the direction using the caterpillar mechanism 4 on the track has the problem of distorting the track. However, since traveling on the stairs 39 is performed by the caterpillar mechanism 4, the caterpillar mechanism 4 requires a direction change means.

[0026]

[Effects of the Invention] As described above, the electric wheelchair according to the present invention has the advantages of being able to improve the degree of freedom of going up and down stairs, and being safe without making the user feel anxious. It has a great effect.

[Brief explanation of drawings]

FIG. 1 is a side view showing an embodiment of an electric wheelchair according to the present invention.

FIG. 2 is a plan view showing an embodiment of the electric wheelchair according to the present invention.

FIG. 3 is a front view showing an embodiment of the electric wheelchair according to the present invention.

FIG. 4 is a rear view showing an embodiment of the electric wheelchair according to the present invention.

FIG. 5 is a schematic diagram of a pressure sensor employed in the electric wheelchair according to the present invention.

FIG. 6 is a schematic diagram of a horizontal detection device and a swing control means provided in a chair employed in the electric wheelchair according to the present invention.

FIG. 7 is a front view of a horizontal detection device employed in the electric wheelchair according to the present invention.

FIG. 8 is a side view of a horizontal detection device employed in the electric wheelchair according to the present invention.

FIG. 9 is an explanatory diagram showing a state in which the electric wheelchair according to the present invention ascends stairs.

FIG. 10 is an explanatory diagram showing a state in which the electric wheelchair according to the present invention descends stairs.

[Explanation of symbols]

1...Electric wheelchair,
2... Main body frame, 2a... Caterpillar frame support part, 3... Caterpillar frame, 4... Caterpillar mechanism, 4a
...Large follower wheel, 4b...Small follower wheel,
4c... Drive wheel, 4d, 4e, 4f, 4g... Intermediate follower wheel, 5... Sprocket, 6a, 6b...
・Travel motor, 7... Sprocket, 8
... Drive belt, 9 ... Caterpillar belt, 10, 11, 12 ... Pressure sensor, 13 ... Support piece, 14 ... Rotating shaft,
15...Sensor body, 15a...Groove,
16...Spring, 17...Pressure switch, 1
8... Direction changing motor, 19... Direction changing wheel, 1
9a...Pressure sensor, 20...Power battery, 21.
...chair, 22...swing axis,
23... Reduction gear, 24... Swing motor, 2
5...First potentiometer, 26...Control lever, 27...Power cylinder for caterpillar swing 27a...
Rod end, 28... Rotating shaft, 29... Horizontal detection device, 3
0...Liquid, 31...Box body,
32... Rotating shaft, 33... Plate piece,
34... Weight, 35... Coupling,
36... Second potentiometer, 37... Support wall,
38...controller, 39...stairs.

Claims (1)

[Claims] 1. An electric wheelchair comprising a caterpillar mechanism on both sides of a main body frame on which a chair is supported, wherein the caterpillar frame of the caterpillar mechanism is swingably supported on the front part of the main body frame, and the main body frame The caterpillar frame is supported by a cylinder device from the rear of the body frame, and a direction changing wheel is provided at the rear of the main body frame to protrude downward from the caterpillar mechanism when the cylinder device is retracted, a drive wheel of the caterpillar mechanism,
The chair is equipped with a pressure sensor that detects the load applied to each of the following wheels and the direction-changing wheels, and is equipped with a horizontal support for swingably supporting the chair supported on the main body frame, and for maintaining the chair horizontally. An electric wheelchair characterized by being equipped with a detection device and a swing control means.