JP5068290B2 - Front wheel mechanism of walking assist vehicle - Google Patents

Description

  The present invention relates to an improvement of a step climbing mechanism used for a walking assistance vehicle or the like.

  People with weak legs may use walking assistance vehicles to assist walking or to carry baggage. The user walks while pushing the walking auxiliary vehicle.

  However, when you walk along the sidewalk while pushing the walking assistance vehicle, you often come across steps. In particular, the walking auxiliary vehicle generally has a small wheel diameter, so it is difficult to cross even a step of about 20 mm, and there is an accident that the vehicle is turned forward by the moment of collision with the step and falls.

  On the other hand, if the user pulls a pusher such as a handle toward the front and lifts the front wheel, the step can be crossed. However, when such an operation is taken, many walking assist vehicles are light and tend to lose balance. Also, because the vehicle cannot move forward with the brakes applied, that is, the step cannot be exceeded, the front wheel must be lifted over the step without applying the brake, and extra force is applied to lift the front wheel. Together, the walking assistance vehicle moves forward unexpectedly, and if it is a walking assistance vehicle, the user may fall.

  In order to avoid such a risk, various wheelchairs and walking assistance vehicles capable of overcoming steps are proposed.

  For example, Japanese Patent Application Laid-Open No. 2006-7855 and Japanese Patent Application Laid-Open No. 2008-229254 are patent documents describing inventions relating to such walking assistance vehicles.

  In the invention described in Japanese Patent Laid-Open No. 2006-7855, a holder for rotatably supporting the front wheel is provided so as to be rotatable in the advancing direction, a spring for returning to the original position is interposed, and an auxiliary wheel is provided in front of the front wheel. It is provided.

  The invention described in Japanese Patent Application Laid-Open No. 2008-229254 is provided with a sled member and a front wheel caster at the lower part of the frame so as to be movable up and down with respect to the frame.

JP 2006-7855 A JP 2008-229254 A

  In the invention described in Japanese Patent Application Laid-Open No. 2006-7855, the front wheel moves backward when the step passes and the auxiliary wheel works, so that it can pass over the step as it is, and then the front wheel is moved to its original position by the force of the spring. Is also a mechanism to return. However, when passing through successive steps such as Braille blocks, the front wheels do not return to their original positions, and if they continue walking, the front wheels are caught at the next steps, and the user may lose balance.

  In addition, the wheelchair described in Japanese Patent Application Laid-Open No. 2008-229254 moves not only the sled member but also the front wheel up and down, and there is a problem that when the user sits down, the wheelchair is turned forward.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a front wheel mechanism of a walking assist vehicle that can overcome a step, can overcome even a continuous step, and does not turn forward when seated.

  In order to solve the above problems, the present invention has improved the front wheel mechanism of a conventional walking assistance vehicle, that is, the front wheel mechanism of a walking assistance vehicle in which a holder for rotatably supporting a wheel is attached to the lower part of the frame as follows. .

  Claim 1: The sub-holder is pivotably attached to the holder and attached so that the tip of the sub-holder is closer to the traveling direction than the front wheel, and the diameter of the sub-holder is larger than that of the front wheel. A small, at least one auxiliary wheel is provided, and an elastic member is applied between the holder and the sub-holder to apply the force to rotate the sub-holder downward. The lower end of the auxiliary wheel is located above the lower end of the front wheel. To control the rotation of the sub-holder.

  [2] The front wheel mechanism according to [1], wherein the sub-holder is provided with a contact member, and the contact member abuts the holder to control the rotation of the sub-holder.

  Hereinafter, it will be described with reference to the drawings what effects the present invention configured as described above has.

  The diameter of the front wheel of a general walking assistance vehicle is about 130 mm, and a step of about 15 mm can be overcome without the action of the auxiliary wheel. However, if the step height exceeds 20 mm, when the front wheel collides with the step, the step cannot be exceeded only by the front wheel, and the handle is lifted by the impact.

  However, according to the front wheel mechanism according to the present invention, the auxiliary wheel 5 is located in front of the front wheel 2 and higher than the front wheel 2. Therefore, when the front wheel 2 collides with a step 12 as shown in FIG. 2, for example, exceeding 20 mm, if the handle 8 moves up, the auxiliary wheel 5 comes into contact with the top of the step 12 and the handle 8 is lifted. Suppress movement. Moreover, since the sub-holder 4 to which the auxiliary wheel 5 is attached is rotated upward, and the sub-holder 4 is given a force to rotate downward by the elastic member 9, the sub-holder 4 tries to rotate downward. The main holder 3, and hence the front wheel 2, is lifted by the force to be applied, and it is possible to exceed the step 12.

  In addition, according to the present invention, even if the steps are continuous, the front wheel 2 is lifted each time the auxiliary wheel 5 comes into contact with each step, so that it is possible to get over smoothly.

  Furthermore, since the front wheel 2 itself does not move up and down, it does not sink when seated, that is, there is no fear of falling forward and falling.

  In addition, since the auxiliary wheel is in the traveling direction side of the front wheel and higher than the ground, even if the auxiliary wheel collides with a step that cannot be exceeded even if the auxiliary wheel is provided, the auxiliary wheel and the step contact with each other. It is possible to suppress the force that the auxiliary vehicle can lean forward.

a Schematic side view showing an embodiment of a front wheel mechanism according to the present invention b Schematic plan view showing a sub-holder and an auxiliary wheel a Explanatory drawing which shows the effect | action of the front-wheel mechanism which concerns on this invention b Explanatory drawing which shows the effect | action of the front-wheel mechanism concerning this invention Schematic side view showing another embodiment of the front wheel mechanism according to the present invention Schematic side view showing another embodiment of the front wheel mechanism according to the present invention The perspective view which shows one Embodiment of a walk auxiliary vehicle

  Hereinafter, a case where an embodiment of a front wheel mechanism according to the present invention is used in a walking assistance vehicle will be described with reference to the drawings.

  In the front wheel mechanism according to the present invention, a holder 3 is fixed to a lower end of a front wheel frame 1a by a fixing pin 10 as shown in FIG. A front wheel 2 is rotatably supported by the holder 3 and a sub-holder 4 is rotatably supported. The shaft 11 serves as both the rotation shaft of the front wheel 2 and the rotation shaft of the sub holder 4.

  As shown in FIG. 1 b and FIG. 5, the sub-holder 4 is a plate that is bent so as to sandwich the holder 3, and an auxiliary wheel 5 is rotatable around the rotation shaft 5 a at the tip in the traveling direction. And it is attached in the form which comes ahead rather than the front wheel 2.

  Further, at the rear end of the sub-holder 4, a shaft 14a as a contact member 14 is provided between the side walls 4b and 4b. The contact member 14 is disposed behind the vertical imaginary line 13 of the shaft 11. For this reason, the contact member 14 abuts against the holder 3, thereby rotating the sub holder 4 downward. Movement is controlled. That is, the lower end of the auxiliary wheel 5 is configured to be positioned above the lower end of the front wheel 2.

  In addition, the contact member 14 is not restricted to a shaft form, For example, a protrusion etc. can be substituted.

  An elastic member 6 is interposed between the holder 3 and the sub-holder 4. Specifically, the lower end of the elastic member 6 serving as a push spring is fixed to the bottom 4 a of the sub-holder 4, while the upper end is fitted into a recess 3 a provided in the holder 3. Thereby, the sub holder 4 is given a force to rotate downward.

The elastic member 6 may use a leaf spring or a tension spring in addition to a push spring as shown in FIGS. As shown in FIG. 3, the leaf spring 6 is interposed between the holder 3 and the contact member 14 constituting the sub-holder. The tension spring 6 is interposed between the contact member 14 and the holder 3 on the side opposite to the imaginary line 13 in the traveling direction. FIG. 3 shows a case where the present invention is implemented in a walking assistance vehicle. The walking assist vehicle 7 is provided with a handle portion 8 gripped by a user at the top, and a pair of front wheels 2 and a pair of rear wheels 15 are rotatably attached to the lower end of the frame 1. At the lower end of the front wheel frame 1a, the holder 3, the sub-holder 4, and other front wheel mechanisms according to the present invention are mounted.

2. Front wheel 3 Holder 4 Sub holder 5 Auxiliary wheel 6 Elastic member 14 Contact member

Claims (1)

In the front wheel mechanism of the walking assistance vehicle, which has a holder that supports the wheel rotatably at the bottom of the frame,
The sub holder can be rotated with respect to the holder, and the tip of the sub holder is attached in a form that comes closer to the traveling direction than the front wheel,
At least one auxiliary wheel having a diameter smaller than that of the front wheel is provided at the front end of the sub holder in the traveling direction.
Between the holder and the sub-holder, an elastic member that applies a force to rotate the sub-holder downward is interposed,
By controlling the rotation of the sub holder so that the lower end of the auxiliary wheel is positioned above the lower end of the front wheel by providing a contact member on the sub holder,
A front wheel mechanism of a walking assistance vehicle characterized by

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