JP2004255168A - Motor-driven wheelchair - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor-driven wheelchair having a steering mechanism capable of effectively utilizing the space around a handle shaft, and capable of improving weight balance and maintainability of a battery. <P>SOLUTION: The motor-driven wheelchair has a frame 2, wheels 4, a handle 5, the handle shaft 6 and the wheel steering mechanism 7. The handle shaft 6 is constituted so that it is turned with the same angle as the handle 5 when the handle 5 is rotated in the shape protruding forward at the middle part. At this time, although the wheel steering mechanism 7 connected to the other end is turned, the locus which the handle shaft 6 traces when it moves occupies the part apart from the rotation center of the handle shaft 6, and a free region is increased toward the rear direction of the handle shaft 6. Also, a battery is arranged in the neighborhood of the acquired free region or the handle shaft. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to an electric wheelchair and a steering mechanism of the electric wheelchair.

  A general self-operating handle type electric wheelchair currently on the market includes a handle, a wheel steering mechanism for steering the wheel left and right, and a handle shaft for transmitting the rotational force of the handle to the wheel steering mechanism. The user sits on the chair, grasps the handle with the arm extended slightly, rotates the handle like a bicycle, and the steering shaft transmits the rotational force to the wheel steering mechanism so that the wheel is steered and the desired traveling direction Have gained.

  Generally, the handle is provided in the vicinity of the user's knee so that the user can hold the handle in a comfortable posture while sitting on the chair. Further, the wheel steering mechanism is provided at the midpoint between the left and right front wheels in a four-wheeled vehicle, and in the upper part of the front wheel in a three-wheeled vehicle. The handle shaft mechanically connects the handle and the wheel steering mechanism.

  At this time, the handle shaft passes between both feet of the sitting user. For this reason, when getting on and off, the user must get on and off the handle shaft, and always take a posture avoiding the handle shaft while getting on and off.

  In addition, the electric wheelchair generally has a large rear weight distribution. This is because the user's ride center of gravity is on the rear side. If the weight distribution is tilted backward, there is a risk of losing balance such as when climbing a hill. Here, if a heavy battery can be installed in the front, this problem can be improved. However, a steering shaft as a steering mechanism passes through the front of the vehicle body. For example, the battery volume is within the dimensions defined by the JIS standard. If it was large, it would interfere with the handle shaft, making placement difficult.

  In conventional electric wheelchairs, as described in Japanese Utility Model Publication No. Hei 6-81523, a heavy battery is arranged near the lower part of the chair, so the weight distribution tends to be inclined backward, and the weight distribution in the front and rear is It was difficult to equalize. Further, when replacing the battery, it is common to replace the battery after removing covers such as a chair and a cowl from the vehicle body, which requires a lot of maintenance work.

  The above-mentioned conventional electric wheelchair has a poor weight balance, poor battery maintenance, and the front part of the electric vehicle has a handle shaft and a front wheel steering mechanism, which can be used effectively within limited dimensions. There was a problem that it was difficult. The present invention solves the above problems and provides a comfortable and safe electric vehicle for the user.

  In order to achieve the above object, according to the first aspect of the present invention, the weight balance between the front and rear is improved by arranging a heavy battery near the lower portion of the handle shaft, and the battery or the like can be removed without removing the chair. Maintenance is possible.

  In the invention of claim 2 and claim 3, the handle operated by the user, the wheel steering mechanism for steering the wheel to the left and right, and the handle shaft connecting the two are arranged at a position away from the operation rotation axis of the handle shaft. Provide effective space near the steering mechanism.

  As described above, the steering mechanism of the electric vehicle according to the present invention has little change from the conventional configuration, and the free area can be expanded at low cost only by changing the shape of the handle shaft, and the maximum dimension is limited. The electric wheelchair makes effective use of valuable space, which contributes to improving user comfort and driving safety of electric vehicles.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an embodiment of claim 1. The electric wheelchair 1 includes a frame 2, a chair 3, wheels 4, a handle 5, a handle shaft 6, a bearing 8, a subframe 9, a battery 10, and a motor 11. As shown in FIG. 2, the end of the handle shaft 6 is connected to the handle 5, and the other end is connected to the wheel steering mechanism 7. The wheel steering mechanism 7 is connected to the wheel 4 and steers the wheel 4 left and right. The battery 10 is installed near the lower portion of the handle shaft 6.

  This improves the front-rear weight distribution of the vehicle body toward equalization. In addition, the battery can be maintained without removing the chair or the like.

  Embodiments of claim 2 and claim 3 are shown in FIGS. The end of the handle shaft 6 is connected to the handle 5 and the other end is connected to the wheel steering mechanism 7. The wheel steering mechanism 7 is connected to the wheel 4 and steers the wheel 4 left and right. The handle shaft 6 protrudes in the middle in the traveling direction. The handle shaft 6 is rotatably held via bearings 8 fixed to the upper and lower parts of the subframe 9. The sub frame 9 is fixed to the frame 2 so that the handle shaft 6 does not wobble.

  When the handle 5 is rotated, the handle shaft 6 is rotated by the same angle as the handle 5 and the wheel steering mechanism 7 connected to the other end is rotated. As shown in FIG. 5, when the locus drawn when the handle shaft 6 moves is seen in a horizontal cross section at a portion where the handle shaft 6 protrudes, a portion which is like the locus 101 and is separated from the rotation center 102 of the handle shaft 6. Can be seen.

  The steering angle of a general electric vehicle is 45 degrees from the center, about 90 degrees in total. When the handle shaft 6 rotates within this angular range, the free region 103a that does not interfere with the handle shaft 6 is shaded. It is shown.

  On the other hand, similarly in the conventional steering mechanism, the free region becomes the hatched portion 103b of FIG. 6, and it can be seen that the free region 103a of the present invention is wider. This area is where the user's knees 104 and legs are located. By expanding the free area 103a according to the present invention, the user is freed from cramped thoughts and contributes to comfortable use of the electric vehicle.

  According to the invention of claim 3, it is also possible to make the handle shaft 6 project backward in the direction opposite to the traveling direction. At this time, the trajectory drawn by the movement of the handle shaft 6 is reverse to the previous embodiment, and the free region at the front of the vehicle body is enlarged.

  As a result, the battery 10 or other devices can be installed in the enlarged free area of the front portion of the vehicle body, and the front-rear weight distribution of the vehicle body is improved toward equalization.

  Further, as shown in FIG. 7, the space of the user's knee 104 and the space for installing the battery 10 and the like are expanded by combining the middle of the handle shaft 6 in the forward direction and the lower portion in the backward direction. It is also possible to ensure both.

  In addition, the free region can be secured by protruding the handle shaft 6 from the rotation center 102 by protruding the handle shaft 6 in the necessary direction not only in the upper, middle, and lower portions of the handle shaft 6 but in the necessary direction. Can be secured.

The block diagram of the electric wheelchair which concerns on the form of the Example of this invention Perspective view of steering mechanism of electric wheelchair The block diagram of the electric wheelchair which concerns on the form of the Example of this invention The perspective view of the steering mechanism part of the electric wheelchair which concerns on the form of the Example of this invention. Cross-sectional view of the operation trajectory of the steering mechanism Sectional view of the cross-section trajectory of the conventional steering mechanism The perspective view of the steering mechanism part of the Example of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric wheelchair 2 Frame 3 Chair 4 Wheel 5 Handle 6 Handle shaft 7 Wheel steering mechanism 8 Bearing 9 Subframe 10 Battery 11 Motor

Claims (3)

  An electric wheelchair comprising a handle, a wheel steering mechanism that is rotatably held by a frame and steers the wheel left and right, and a handle shaft having one end joined to the wheel steering mechanism and the other end fixed to the handle. An electric wheelchair characterized by mounting a battery near the lower portion of the shaft.   In a steering mechanism of an electric wheelchair provided with a handle, a wheel steering mechanism that is rotatably held by a frame and steers the wheel left and right, and a handle shaft having one end joined to the wheel steering mechanism and the other end fixed to the handle A steering mechanism for an electric vehicle, wherein the handle shaft is disposed at a position away from a rotation center at which the handle shaft operates when the handle is operated.   3. An electric wheelchair equipped with a steering mechanism according to claim 2, wherein a battery is mounted near the lower portion of the handle shaft.