JP3775955B2 - vehicle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle such as an automatic guided vehicle.
[0002]
[Prior art]
Conventionally, as an example of an automatic guided vehicle, there are those shown in FIGS. This is because a support shaft 2 is disposed along the transverse direction in the center of the vehicle body 1 and two traveling drives are arranged in the swing frame 3 suspended on the support shaft 2 so as to be swingable in the directions of arrows a and b. The devices 4A and 4B are provided symmetrically about the support shaft 2, and each of the travel drive devices 4A and 4B rotationally drives a pair of left and right drive wheels 5a to 5d by a drive motor 7 via a differential mechanism 6. It is what you do. In FIG. 5, 8 is a front wheel and 9 is a battery.
[0003]
In the above configuration, the vehicle body 1 is caused to travel in the front-rear directions c and d by rotating the four drive wheels 5a to 5d forward and backward by the drive motor 7 of each of the travel drive devices 4A and 4B. The swing frame 3 is swung a and b around the shaft 2 so that the drive wheels 5a to 5d are grounded to the travel road surface G, and the travel direction of the vehicle body 1 can be changed by the differential mechanism 6. It has become.
[0004]
[Problems to be solved by the invention]
In the conventional configuration, as shown in FIG. 8, among the driving wheels 5 a to 5 d, for example, the driving wheel 5 a on the left front side is fitted into the recess (or step) g of the traveling road surface G and the wheel pressure is reduced. When slipping due to this (see the phantom line in FIG. 8), the differential mechanism 6 is damaged, and the driving force is not transmitted to the driving wheel 5b opposite to the driving wheel 5a that slips and idles. Further, by combining the two drive motors 7 in a series circuit, most of the current flows through the drive motor 7 of the light load side, that is, the front travel drive device 4A, and almost no current flows through the rear travel drive device 4B. Does not flow, both rear drive wheels 5c. 5d is not rotated. Accordingly, neither the traveling drive devices 4A and 4B generate a driving force, only the idling of the slipping drive wheels 5a increases, and the automatic guided vehicle falls into a state in which it cannot travel.
[0005]
An object of the present invention is to provide a vehicle capable of continuing traveling even when one of the drive wheels is fitted into a recess or a step in view of the above-described conventional drawbacks.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the invention described in claim 1 includes a travel drive device in which a pair of left and right drive wheels are rotationally driven by a drive motor via a differential mechanism, and the travel drive device is provided in the longitudinal direction of the vehicle body. Are arranged close to each other at a predetermined interval, and when a load is unbalanced in the drive motors of the both travel drive devices, a circuit is formed to pass a larger amount of current to the light load side drive motor. In the vehicle, a pair of left and right power transmission mechanisms are provided between the two travel drive devices to interlock the two driving wheels facing each other along the front-rear direction, and the pair of power transmission mechanisms can move up and down on the vehicle body. And a pressing means for pressing the road tire against the outer peripheral surfaces of both drive wheels facing each other in the front-rear direction .
[0007]
According to the above configuration, even when one of the drive wheels, for example, the front left drive wheel slips into a recess (or step) on the traveling road surface, the rear left side via the left power transmission mechanism. Since the power generated by slipping due to slip is transmitted to the driving wheel of the vehicle, driving force is generated in the rear traveling drive device, and the vehicle body can be driven by the driving force to immediately eliminate the slipping state due to slipping. .
[0008]
In addition, by simply pressing the road tire against the outer peripheral surfaces of both driving wheels facing each other in the front-rear direction by the pressing means, power can be reliably transmitted from one driving wheel to the other driving wheel. Easy and cheap to produce.
[0009]
The invention described in claim 2 is characterized in that, in the invention described in claim 1 , the pressing means comprises a spring.
[0010]
According to the above configuration, the road tire is pressed against the drive wheel by the spring at a substantially constant pressure, so that the power transmission function can be maintained over a long period of time even if the wear of each drive wheel and the road tire increases.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
1 to 3 show an automatic guided vehicle according to an embodiment of the present invention, and both drive wheels 5a and 5c that face each other in the front-rear direction between two front and rear traveling drive devices 4A and 4B. A pair of left and right power transmission mechanisms 11 for interlockingly connecting 5b and 5d are provided. Since the configuration other than the above is substantially the same as the conventional example shown in FIGS. 5 to 8, the same reference numerals are given to the same portions and the description thereof is omitted.
[0012]
As shown in FIG. 4, the power transmission mechanism 11 includes a steel plate support frame 12 bent upward from the side surface of the swing frame 3, and a substantially L-shaped steel lift frame 13 on the support frame 12. A road tire 14 made of an elastic material such as rubber supported so as to be movable up and down, and the road tire 14 is pivotally supported by a vertical portion 13a of the elevating frame 13 via a rotating shaft 15, An upper end small diameter portion 16a of the vertical axis 16 standing on the horizontal portion 13b of the elevating frame 13 is inserted in a through hole 17 penetrating the distal end horizontal portion 12a of the support frame 12 so as to be able to move up and down, and a male screw of the upper end small diameter portion 16a. A spring (pressing means) 20 is provided in which a retaining nut 19 is screwed into the part via a washer 18 and is externally fitted to the vertical axis 16 to urge the lifting frame 13 downward. As shown in FIGS. 1 to 3, the support shaft 2 is rotatably inserted into a cylindrical shaft 3 a fixed to the central portion of the swing frame 3, and both ends of the support shaft 2 are top plates of the vehicle body 1. It is fixed to a pair of left and right bearing plates 21 depending from the part.
[0013]
According to the above configuration, as shown in FIG. 1, one of the driving wheels 5 a to 5 d, for example, the driving wheel 5 a on the left front side fits into the recess (or step) g of the traveling road surface G and slips. In this case, the road tire 14 that is in pressure contact with the drive wheel 5a is rotated, and the power generated by slipping due to slip is transmitted to the drive wheel 5c on the rear left side that is in pressure contact with the road tire 14, so the rear traveling drive device 4B A driving force is generated, and the vehicle body 1 is caused to travel by the driving force, so that the idling state due to the slip can be immediately resolved.
[0014]
In addition, since the road tire 14 is pressed against the driving wheels 5a to 5d by the spring 20 at a substantially constant pressure, even if the driving wheels 5a to 5d and the road tire 14 are worn significantly, the power transmission function is maintained for a long time. can do. Furthermore, the structure of the power transmission mechanism 11 is simple and the manufacturing cost is low.
[0015]
In the above embodiment, the automatic guided vehicle has been described as an example, but the present invention can also be applied to various other vehicles. Moreover, although the spring 20 was used as a pressing means of the road tire 14, other than this, for example, a gas cylinder or the like may be used.
[0016]
【The invention's effect】
According to the first aspect of the present invention, even if one of the driving wheels, for example, the driving wheel on the left front side is fitted into the recess (or step) on the traveling road surface and slips, the power transmission mechanism on the left side is Because the power generated by slipping due to slip is transmitted to the driving wheel on the left rear side, driving force is generated in the rear traveling drive device, and the vehicle body is driven by that driving force to immediately eliminate the slipping state due to slipping. can do.
[0017]
In addition, by simply pressing the road tire against the outer peripheral surfaces of both driving wheels facing each other in the front-rear direction by the pressing means, power can be reliably transmitted from one driving wheel to the other driving wheel. Easy and cheap to produce.
[0018]
According to the second aspect of the present invention, the road tire is pressed against the driving wheel by the spring at a substantially constant pressure, so that the power transmission function is maintained over a long period of time even if the wear of each driving wheel and the road tire increases. be able to.
[Brief description of the drawings]
FIG. 1 is a side view of a main part of an automatic guided vehicle according to an embodiment of the present invention.
FIG. 2 is a partially cutaway plan view of the main part.
FIG. 3 is a cross-sectional view of the main part.
FIG. 4 is an exploded perspective view of the power transmission mechanism.
FIG. 5 is a side view of a conventional automatic guided vehicle.
FIG. 6 is a plan view of the same.
FIG. 7 is a front view of the same.
FIG. 8 is a side view of the main part.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Car body 4A, 4B Travel drive device 6 Differential mechanism 11 Power transmission mechanism 14 Road tire 20 Spring (pressing means)

Claims (2)

A pair of right and left drive wheels via a differential mechanism includes a travel drive apparatus adapted to rotated by a driving motor, the travel drive device is provided close at two predetermined intervals in the longitudinal direction of the vehicle body, the In a vehicle in which a circuit for passing a large amount of current to the light load side drive motor when an imbalance occurs in the load of each drive motor of both travel drive devices ,
A pair of left and right power transmission mechanisms for interlockingly connecting the two drive wheels facing each other along the front-rear direction are provided between the both travel drive devices,
The pair of power transmission mechanisms includes a road tire supported by a vehicle body so as to be movable up and down, and pressing means for pressing the road tire against outer peripheral surfaces of both drive wheels facing each other in the front-rear direction. vehicle.   The vehicle according to claim 1, wherein the pressing means includes a spring.

Images