JP4180709B2 - Electric wheelchair - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electric wheelchair. More specifically, the present invention relates to an electric wheelchair in which a user can move forward, backward, and turn by operating his / her hand.
[0002]
[Background Art and Problems to be Solved by the Invention]
As shown in FIG. 5, a conventional electric wheelchair 51 has a large-diameter driving wheel 53 disposed at the rear portion of a vehicle body 52, and a front wheel 54 serving as a small-diameter driven wheel disposed at the front portion of the vehicle body 52. A motor 55 as a drive source is connected to the drive wheel 53. The front wheel 54 is mounted so as to be rotatable about its support shaft 56, and its direction can be freely changed according to the traveling direction.
[0003]
A control box 57 is disposed at the tip of the right elbow rest 56 of the vehicle body 52. The user tilts the operation knob 58 in the traveling direction (including retreat) to individually change the rotational speed of the left and right drive wheels 53 to move the electric wheelchair 51 forward, turn, and retreat. Further, the moving speed is changed.
[0004]
Extending forward from between the left and right front wheels 54 is a so-called climbing wheel 59, which is arranged at a position floating upward from the ground, and has an effect when climbing over a step on the ground. A foot step 60 for placing a user's foot is disposed further forward of the climbing wheel 59. The foot step 60 has a step plate 62 rotatably attached to each of the left and right arms 61 extending forward. The step plate 62 can rotate in the left-right direction around the arm 61 from a substantially horizontal use position to a substantially vertical non-use position.
[0005]
The overall shape of the electric wheelchair 51 is the same as that of a manual wheelchair, and a seat 63 on which a user is seated is fixed at an intermediate position between the drive wheel 53 and the front wheel 54. That is, the center of the seat 63 is located considerably forward of the axle (not shown) of the drive wheel 53. On the other hand, since the electric wheelchair 51 turns due to the difference in rotational speed between the left and right drive wheels 53, the vehicle body 52 may turn around the center point between the drive wheels 53 (the center point of the drive wheel axle). . Therefore, at the time of such turning, the user is also turned by a certain radius around the center point of the drive wheel axle, and at that time, the user is facing outward in the radial direction of his or her turning circle.
[0006]
As a result, when riding on the electric wheelchair 51 and traveling through a narrow and bent path, or when an obstacle is detoured by a small turn, the operation becomes difficult. That is, when turning the electric wheelchair 51, it is difficult to instantly predict where the next position / direction will be, and it is far from the ideal of handling the electric wheelchair 51 like its own limbs. . In other words, for example, large trucks and buses with front wheels located behind the driver's seat have a similar degree to the extent that it is difficult for the driver to turn the vehicle body, particularly with a small radius. I have a sense.
[0007]
However, the above problem does not occur conspicuously when turning the vehicle body with a large turning radius.
[0008]
The present invention has been made to solve such a problem, and provides a convenient electric wheelchair that can instantly predict where the next position / direction will be when the user turns the vehicle body. The purpose is that.
[0009]
[Means for Solving the Problems]
The electric wheelchair of the present invention is
A main body, electric driving wheels disposed on the left and right of the main body, a driven wheel disposed on the rear side of the driving wheel in the main body, and between the driving wheels on the main body and on the rear side thereof The rotation ratio of the two drive wheels can be freely changed.
[0010]
Therefore, the user seated on the seat is positioned on the middle of the two driving wheels or on the rear side thereof. In other words, when the electric wheelchair is turned around the middle point between the two drive wheels, the user is positioned on or behind the turning center. As a result, the electric wheelchair turns around the user's body or turns around a position slightly ahead of the user's body. Then, the user can instantly predict his / her own position and direction during and after the turn, and it becomes easy to handle.
[0011]
The pair of left and right step climbing wheels in front of the drive wheels in the main body are arranged so that the lower ends thereof are located above the lower ends of the drive wheels, so that the steps can be easily overcome. The wheel is placed in the middle and the driven wheel at the rear and the step-over wheel at the front are placed and stabilized. Since the climbing wheels are a pair of left and right, the vehicle body is stable when climbing over a step, and the vehicle body is stably supported when tilting forward with the driving wheel as a fulcrum.
[0012]
In addition, by attaching the seat so that the approximate center of the seat corresponds to the approximate center of the imaginary straight line connecting the centers of the two drive wheels, the vehicle body is always turned when the vehicle itself is centered. Since the user turns about the user himself / herself, even when the turning radius is small, it is easy to handle as described above.
[0013]
Furthermore, by attaching the seat so that the position in the front-rear direction with respect to the main body can be adjusted, the user can select the seating position with respect to the turning center according to his / her physique.
[0014]
In addition, a foot step for placing a user's foot is disposed between the pair of left and right step climbing wheels so that the foot step can swing upward and be stored on the main body side. By comprising, it is prevented that it becomes obstructive by storing a foot step at the time of a user's boarding / alighting. Moreover, it can arrange | position ahead without interfering with a level | step climbing wheel.
[0015]
In addition, it has a drive wheel support arm and a ride-over wheel arm, the rear end of the drive wheel support arm is elastically attached to the main body frame, the vicinity of the front end is pivotally supported on the main body frame, and the drive wheel is arranged in the middle part. The rider wheel is pivotally supported at the rear end of the rider wheel arm, the rider wheel is disposed at the front end, and the intermediate part is elastically attached to the front end of the drive wheel support arm. Since the downward pressing force acts on the drive wheel when the vehicle rides on the step, the ground contact force is maintained. As a result, high running performance can be obtained even when traveling on a level difference.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the electric wheelchair of the present invention will be described with reference to the accompanying drawings.
[0017]
FIG. 1 is a perspective view showing an embodiment of an electric wheelchair according to the present invention. 2 is a cross-sectional view showing a semi-disassembled state of the electric wheelchair of FIG. FIG. 3 is a perspective plan view of the electric wheelchair of FIG. FIG. 4 is a side view showing an example of a main part of the electric wheelchair shown in FIG.
[0018]
The electric wheelchair 1 shown in FIGS. 1 to 3 has left and right large-diameter drive wheels 2 disposed slightly forward from the center of the main body frame 3, and a small-diameter rear wheel 4 as a driven wheel at the rear of the main body frame 3. A small-diameter step-over wheel (hereinafter referred to as a “ride-over wheel”) 5 is disposed at the front portion of the main body frame 3. As shown in FIG. 2, the right elbow rest 6 is provided with a control box 7 (not shown in FIGS. 1 and 3).
[0019]
A drive motor (not shown) is connected to the drive wheel 2. By operating the operation knob 7a of the control box 7, the rotational speeds of the left and right drive wheels 2 are individually changed, whereby the electric wheelchair 1 is moved forward, turned, and retracted. Furthermore, the moving speed can be changed. The drive wheel 2 is elastically attached to the main body frame 3 by interposing a coil spring 8.
[0020]
A body cover 9 is detachably attached to the main body frame 3. Further, as shown in FIGS. 2 and 3, a boss 11 for detachably fitting the seat 10 is disposed slightly behind the drive wheel shaft 2 a in the main body frame 3. As shown in FIG. 2, a shaft member 12 fitted into the boss 11 is attached to the lower surface of the sheet 10. A mounting bolt 13 protruding from the upper surface of the shaft member 12 is rotatably attached. On the other hand, a plate member 14 in which a plurality of nuts 14 a are embedded is disposed on the lower surface of the sheet 10. By doing so, the front-rear position of the shaft member 12 relative to the seat 10 can be changed and adjusted, and as a result, the front-rear position of the seat 10 relative to the main body frame 3 can be changed and adjusted. The seat 10 is not limited to the bolt 13 and the nut 14a, and can be attached to the vehicle body frame 3 so that the front-rear position can be adjusted by known means.
[0021]
In the present embodiment, the center position of the seat 10 just corresponds to a virtual straight line (shown by a one-dot chain line in FIG. 3) L that connects the centers of the two drive wheels 2, the front position, and the virtual straight line. It can be adjusted between L and the rear position which is an intermediate position between the rear wheels 4. Therefore, when the electric wheelchair 1 is turned around the center point of the virtual straight line L, that is, one of the left and right drive wheels is rotated in the forward direction, and the other drive wheel is rotated at the same rotational speed in the update direction. When this is done, it can be swiveled about the user itself (when the seat 10 is in the front position), making it easier to handle. When the seat 10 is in the rear position, the turning center of the electric wheelchair 1 exists in front of the user. Therefore, since the turning center exists in the user's field of view, it is possible to instantaneously predict the direction and position of the user at the time of turning, and the handling becomes easy.
[0022]
The rear wheel 4 is rotatably attached to a support shaft 15 formed at the rear end of the main body frame 3 in a horizontal plane (see FIG. 3). Therefore, the drive wheel 2 rotates in conformity with the traveling direction.
[0023]
Here, with reference to FIGS. 2 and 4, the attachment mechanism between the drive wheel 2 and the overpass wheel 5 will be described in relation to both 2 and 5. FIG. 4 shows a state in which the front driving wheel 2 is removed for the sake of clarity. The illustrated driving wheel 2 is a driving wheel on the other side.
[0024]
First, a support portion 3 a extending downward is projected from the front portion of the main body frame 3. A first pin 17 that rotatably supports a part of a drive wheel support arm 16 that will be described later is rotatably supported on the support portion 3a, and one end of a climbing wheel arm 18 that is described later is rotatably supported below the first pin 17. A second pin 19 is provided. The climbing wheel 5 is attached to the vicinity of the front ends of the pair of left and right climbing wheel arms 18 extending forward from the main body frame 3 so as to float slightly above the lower ends of the drive wheels and the rear wheels. An intermediate portion of the climbing wheel arm 18 is elastically attached to a front end portion of a driving wheel support arm 16 to be described later via a coil spring 20, and a rear end is pivotally supported on the support portion 3a by the second pin 19. ing. Therefore, when the climbing wheel 5 rides on the step, the climbing wheel arm 18 is swung upward with the second pin 19 as a fulcrum.
[0025]
On the other hand, the rear end of the drive wheel support arm 16 is attached to the main body frame 3 via the coil spring 8, and a portion from the rear side of the front end is pivotally supported on the support portion 3 a by the first pin 17. Yes. In addition, the axle of the drive wheel 2 is attached between the portion of the coil spring 8 in the drive wheel support arm 16 and the pivot portion by 17 on the first pin. Therefore, when the front end of the drive wheel support arm 16 is pushed upward with the first pin 17 as a fulcrum, the drive wheel 2 is lowered downward, and when the front end is pushed downward, the drive wheel 2 is raised upward.
[0026]
With this configuration, as shown in FIG. 4, when the overpass wheel 5 rides on the level difference H, the front end of the overpass wheel arm 18 is pushed upward, so that a downward pressing force acts on the drive wheel 2 and the drive wheel 2 The grounding force is maintained. As a result, high running performance can be obtained even when traveling on a level difference. In FIG. 4, the state in which the driving wheel 2 is pushed down is indicated by a two-dot chain line. However, the driving wheel 2 is not actually lowered, and the coil 8 is compressed to prevent the driving wheel 2 from reducing the force pressing the ground. It is.
[0027]
As shown in FIG. 3, a foot step 21 for the user to place his / her foot is disposed between the pair of climbing wheels 5. As shown in FIG. 2, the foot step 21 is swingably attached to the tip end of a substantially L-shaped arm 22 projecting forward from the front portion of the main body frame 3. Then, it is swung upward from a substantially horizontal state of use and is stored close to the main body frame 3 from substantially vertical.
[0028]
When the user gets on the electric wheelchair 1, the user generally sits on the seat with the foot step 21 stored, and then swings to the use state. However, there is a case where the footstep 21 is tried to get on the footstep 21 with the footstep 21 in a horizontal state. At that time, even if the electric wheelchair 1 tilts forward and downward with the driving wheel 2 as a fulcrum, the left and right riding wheels 5 land and are supported at four points by the riding wheel 5 and the driving wheels 2 that do not rotate carelessly. So it becomes stable. This is because the conventional electric wheelchair 51 shown in FIG. 4 is supported by a single ride-over wheel 59 with a pivotable front wheel (driven wheel) 54 as a fulcrum when tilting forward and downward in the same state. In contrast.
[0029]
In FIG. 1, an operation lever denoted by reference numeral 23 is for rotating the seat 10 for the convenience of getting on and off by the user.
[0030]
【The invention's effect】
According to the present invention, the user seated on the seat is located on the middle of the two drive wheels or on the rear side thereof. That is, when the electric wheelchair is turned around an intermediate point between the two drive wheels, and when the electric wheelchair is turned with a small radius close thereto, the user is positioned on or behind the turning center. As a result, the electric wheelchair turns around the user's body or turns around a position slightly ahead of the user's body. Then, the user can instantly predict his / her own position and direction during and after the turn, making it easier to handle.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of an electric wheelchair according to the present invention.
FIG. 2 is a side view showing a half-disassembled state of the electric wheelchair shown in FIG.
3 is a perspective plan view of the electric wheelchair of FIG. 1. FIG.
4 is a side view showing an example of a main part of the electric wheelchair shown in FIG. 1. FIG.
FIG. 5 is a perspective view showing an example of a conventional electric wheelchair.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Electric wheelchair 2 ... Driving wheel 3 ... Body frame 3a ... Support part 4 ... Rear wheel 5 ... Passing wheel 6 ... Elbow rest 7 ... ... Control box 8 ... Coil spring 9 ... Body cover 10 ... Seat 11 ... Boss 12 ... Shaft member 13 ... Mounting bolt 14 ... Plate member 15 ··· Support shaft 16 ··· Driving wheel support arm 17 ··· First pin 18 · · · Passing wheel arm 19 · · · Second pin 20 · · · Coil spring 21 .... Foot step 22 ... Arm 23 ... Operation lever

Claims (4)

A body frame, a drive wheel arranged on the left and right of the body frame,
A driven wheel disposed behind the drive wheel in the main body frame ;
A seat disposed behind the upper and out between the two drive wheels of the main body frame,
A pair of left and right step climbing wheels disposed in front of the drive wheels in the main body frame such that the lower ends thereof are located above the lower ends of the drive wheels;
A drive wheel support arm;
With a climbing wheel arm ,
The rear end of the drive wheel support arm is attached to the main body frame via a coil spring, the vicinity of the front end is rotatably supported by the main body frame, and the drive wheel is disposed in the middle part.
The rear end of the climbing wheel arm is pivotally supported by the body frame, the climbing wheel is disposed at the front end, and the intermediate part is attached to the front end of the driving wheel support arm via a coil spring.
An electric wheelchair configured to freely change the rotation ratio of the both drive wheels. Approximately centrally, substantially mounted such that the center corresponding to the position comprising Claim 1 Symbol mounting of the electric wheelchair of the virtual straight line connecting the centers of both drive wheels of the sheet. The sheet is, according to claim 1 or 2, wherein the electric wheelchair comprising mounted so as to adjust the position in the front-rear direction relative to the body frame. A foot step for placing a user's foot is disposed between the pair of left and right step climbing wheels so that the foot step can swing upward and be stored on the main body frame side. The electric wheelchair according to any one of claims 1 to 3 .

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