JPH107043A - Unmanned conveying vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve an applicability in operation of this kind of unmanned conveying vehicle by a method wherein the unmanned conveying vehicle has the same forwarding locus and reversing locus and has a high reliability about its traveling accurately carried out in response to an instruction performed by a computer. SOLUTION: In an unmanned conveying vehicle 1 in which each of wheels 4a, 4b, 4c and 4d is arranged at positions of four apexes of a rhomb as seen in a top view and a direction of one of orthogonal lines of the rhomb is applied as a forward or rearward direction of the vehicle, the front wheel 4a and the rear wheel 4d on one orthogonal line are applied as steering wheels and connected through an interlocking mechanism 16 interlocked to cause these steering angles to have a reverse phase. Two wheels placed on the other orthogonal line between the front wheel 4a and the rear wheel 4d are applied as driving wheels 4b, 4c. The front wheel 4a and the driving wheels 4b and 4c are supported by an oscillating member 5. the oscillating member 5 is pivotally supported by a pivot shaft 6 directed toward a side of the unmanned conveying vehicle 1 at a position between the front wheel 4a and the driving wheels 4b, 4c and further supported in such a way that it way be oscillated against the vehicle body 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic guided vehicle.

[0002]

2. Description of the Related Art In recent years, various proposals have been made for various types of automatic guided vehicles that transport articles and the like unattended.

[0003] Such an automatic guided vehicle is intended to be used on, for example, a factory premises or a building, and must be able to travel freely in a space such as a narrow passage.
For convenience of controlling such an automatic guided vehicle by a computer and performing its traveling operation, it is preferable that the forward and backward movements of the automatic guided vehicle have the same trajectory.

[0004] Further, since such an automatic guided vehicle travels unmanned, it is necessary on the premise that it has high reliability in traveling faithfully in accordance with a command from a computer.

[0005]

The automatic guided vehicle of this type, which has been proposed in the past, has the same trajectory of forward and backward travel and runs faithfully in accordance with a command from a computer. As a result, the automatic guided vehicles of this type have not yet been fully utilized in practice.

The present invention has been made in view of such circumstances, and the trajectories of forward and reverse travels are the same.
It is an object of the present invention to improve the practicality of this type of automatic guided vehicle by providing the automatic guided vehicle with high reliability of traveling faithfully according to a command from a computer.

[0007]

In order to solve such a problem, according to the present invention, a wheel is provided at each of four vertices of a diamond in plan view, and one diagonal line of the diamond is provided. The front and rear wheels located on the one diagonal line are the steered wheels, and the steering angles of the steered wheels with respect to the one diagonal line are the front wheels and the rear wheels. Between the front and rear wheels, the two wheels located on the other diagonal between the front and rear wheels are set as drive wheels, and the front wheels and the drive wheels are swung. The swing member is pivotally supported by a pivot installed toward the vehicle side of the automatic guided vehicle at a position between the front wheel and the drive wheel so as to swingably support the vehicle body. An automatic guided vehicle characterized by the following.

According to a second aspect of the present invention, there is provided the automatic guided vehicle according to the first aspect, wherein a detecting means for a guide member installed on a road surface is provided at a front portion of the automatic guided vehicle, and the detecting means is provided. Is an automatic guided vehicle mounted on a swing member forward of the front wheel.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in the drawings.

In FIG. 1, reference numeral 1 denotes an automatic guided vehicle, 2 denotes a vehicle body, and 3 denotes a traveling device.

The vehicle body 2 is formed as a monocoque body, and a flat carrier 2a is formed on the upper surface of the vehicle body 2.

The traveling device 3 is shown by a two-dot chain line in FIG.
Four wheels are respectively arranged at positions corresponding to respective vertices of a rhombus in plan view, and 4a is a front steering wheel, 4b and 4c.
Is a drive wheel, and 4d is a rear steering wheel.

In the drawings, an arrow F indicates the front of the automatic guided vehicle 1. Also, in the figure, a line OO is a center line facing the front-rear direction of the automatic guided vehicle 1, and the wheels 4a to 4d
Is also a diagonal line connecting the front steered wheels 4a and the rear steered wheels 4d.

Among these wheels, the rear steered wheels 4d are mounted on the vehicle body 2 so as to be steerable, while the front steered wheels 4a and the drive wheels 4b and 4c are mounted on the swinging member 5. .

The swing member 5 is formed in a frame shape in a plan view, and is formed as a monocoque body via a pivot 6 extending from a central portion of the swing member 5 in the front-rear direction toward the vehicle side. It is pivoted at two required sites.

Therefore, the swing member 5 can swing around the pivot 6, and the front and rear ends of the swing member 5 can be displaced in the vertical direction.

A front steering wheel 4a is provided at a central portion of the swing member 5 in front of the pivot 6.
Drive wheels 4b and 4c are installed at a position behind the pivot 6.

A traveling drive unit 7 is provided from the center of the swing member 5 to a position near the drive wheels 4b and 4c.

The driving device 7 for traveling includes the electric motor 1 for traveling.
1, a drive belt 12, and a differential device 13, and the traveling electric motor 11 is driven by electric power supplied from a storage battery 14 installed on the vehicle body 2 side. The required driving force is transmitted to the moving device 13.

The differential 13 transmits the thus transmitted driving force to the left and right driving wheels 4b and 4c as appropriate, and functions as a so-called differential device.

On the other hand, a steering electric motor 15 is disposed near the front steered wheels 4a installed on the swinging member 5, and the front steered wheels 4a and the rear steered wheels 4d are arranged.
And the following interlocking mechanism 16 for interlocking the two.

That is, as shown in FIGS. 1 and 3, the interlocking mechanism 16 includes the front steering wheel 4a and the rear steering wheel 4d.
Arm portions 18a, 18d extending in the radial direction from the respective steering shafts 17a, 17d, and the respective steered wheels 4a, 4d.
and a connecting rod 19 for interlockingly connecting the arm portions 18a and 18d.

In the interlocking mechanism 16, the extending directions of the arms 18a and 18d are opposite to each other with respect to the center line OO, and the extending directions of the connecting rods 19 from the rotation centers of the respective steering shafts 17a and 17d. Since the lengths of the arms up to the connecting portion are matched, by driving the electric motor 15 for steering, the two steered wheels 4a and 4d are moved along the center line O-.
The steering angles with respect to O are linked so that they have the same value in opposite directions, that is, have opposite phases.

In this embodiment, a spring 2 is provided between the rear end of the swinging member 5 and the vehicle body 2 side.
1 is interposed to prevent the swinging member 5 from swinging excessively sensitively, thereby enabling stable running.

In this embodiment, a large number of optical sensors 22 are arranged at the front end of the swinging member 5 so as to face downward over substantially the entire width of the vehicle as shown in FIG. The front side detection means 23 is provided. The rear-side detecting means 24, which is constituted by a large number of optical sensors 22 like the front-side detecting means 23, is installed at the rear of the vehicle body 2.

These detecting means 23 and 24 emit light toward the road surface and detect the presence of the guide member 25 from the light reflected by the guide member 25 such as a reflective tape installed on the traveling road surface of the automatic guided vehicle 1. Is to be detected. The signals from these detecting means 23 and 24 are input to a computer (not shown), and are used for verifying the running state of the automatic guided vehicle 1 and correcting the running state as necessary.

The automatic guided vehicle 1 configured as described above includes:
There is a function as shown in FIG.

For example, normally, when the transport vehicle reaches the uphill S from the flat road H, slippage is likely to occur. However, the automatic guided vehicle 1 of the present application has the front steered wheels 4a and the drive wheels as described above. Since the swing members 4b and 4c are provided on the swing member 5, the swing member 5 is displaced around the pivot 6, as shown by the solid line in FIG.

Even if the positions of the front steered wheels 4a and the drive wheels 4b and 4c are displaced substantially vertically by the swing of the swing member 5, these front steered wheels 4a and the drive wheels 4b and 4c are displaced.
The relative position of the three wheels does not change, and the state where the three points are located on a single plane is maintained, so that the three wheels are prevented from slipping and the slippage is prevented.

Further, since the swinging of the swinging member 5 is performed around the pivot 6 provided between the front steered wheels 4a and the drive wheels 4b and 4c, the front steered wheels 4a move uphill S. As the vehicle rides, the drive wheels 4b and 4c disposed behind the pivot 6 are pressed against the road surface side of the flat road H below. The vehicle 1 can be reliably driven.

Further, in such a state, the following advantages are further obtained with respect to the front side detection means 23.

In FIG. 5, the imaginary line shows the situation when the automatic guided vehicle 1 is on a flat road H. Compared with the above-described state shown by the solid line, the inclination of the vehicle body 2 is shown in FIG. The angle A is evident from the displacement of the line connecting the upper rear steering wheel 4d and the pivot 6 above.

However, the displacement of the line connecting the front steering wheel 4a and the pivot 6 to which the swing of the swing arm 6 is added is larger than the angle A.

This means that the front side detecting means 23 can be positioned at a required height quickly adapted to the change in the inclination of the road surface by installing the front side detection means 23 on the swinging member 5, and the road surface can be positioned at the required height. The detection of the guide member 25 is reliable,
There is an advantage that the use of the expensive optical sensor 22 having a long focal length can be avoided.

The automatic guided vehicle 1 according to the embodiment described above.
In the above, the driving wheels 4b and 4c are driven from the single traveling electric motor 11 via the differential device 13, but the present invention can be implemented without being limited to such a driving method.

For example, in FIG. 6 in which the description of the interlocking mechanism 16 is omitted, the driving electric motors 11b and 11c are installed independently of each of the drive wheels 4b and 4c, and these driving electric motors 11b and 11c are provided. The same effect as in the above-described embodiment can be enjoyed even if the function as a differential device similar to the differential device 13 is exhibited by electrically controlling the differential device 13.

[0037]

As described above, according to the first aspect of the present invention, the wheels are provided at the four vertices of the diamond in plan view, and the front wheel and the rear wheel located on one diagonal of the diamond are provided. And the front and rear wheels are interlocked so that the steering angles with respect to the one diagonal line have the same value in the opposite directions between the front and rear wheels. , The movement of the automatic guided vehicle can be made the same trajectory.

In this automatic guided vehicle, the front wheel and the drive wheel are supported by a swing member, and the swing member is directed toward the vehicle side of the automatic guided vehicle at a position between the front wheel and the drive wheel. Since the swinging member swings with respect to the inclination of the road surface in the moving direction of the automatic guided vehicle, Can be inclined so that the plane defined by the drive wheels conforms to the inclination of the road surface, and the front wheels and the drive wheels are reliably grounded.

In particular, at the entrance to an uphill from a flat road where the driving wheels are often lifted and slipped, the front wheels are installed behind the axle by being pushed upward on the uphill slope. Since the driving wheels are pressed against the road surface, the driving force is more reliably transmitted to the road surface by the driving wheels.

In other words, according to this automatic guided vehicle, the forward and backward movements have the same trajectory, the driving wheels are reliably grounded, and the driving force is transmitted to the road surface even at the entrance of the uphill. Since it is performed reliably, it also has high reliability in driving faithfully according to instructions from the computer.

Therefore, this automatic guided vehicle has high practicality.

According to the second aspect of the present invention, there is further provided a means for detecting a guiding member installed on a road surface at a front portion of the automatic guided vehicle, and the detecting means includes a swinging member located forward of the front wheel. It is attached to.

In this way, during forward movement, which is often used in automatic guided vehicles, the attitude of the swinging member can be made to correspond more quickly to the change in the inclination of the vehicle body caused by the change in the inclination of the road surface. Since the guide member can be positioned at a required height suitable for the detection, the detection of the guide member by the detection means can be reliably performed, and the computer control of the automatic guided vehicle can be reliably performed.

[Brief description of the drawings]

FIG. 1 is a plan view showing a schematic structure of an automatic guided vehicle.

FIG. 2 is a side view of the automatic guided vehicle with a part cut away.

FIG. 3 is a side view showing an interlocking mechanism between a front wheel and a rear wheel.

FIG. 4 is a front view schematically showing a detection unit.

FIG. 5 is an explanatory diagram of the operation of the swing member.

FIG. 6 is a schematic explanatory view of an automatic guided vehicle according to another embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 automatic guided vehicle 2 body 4a front steered wheels (front wheels) 4b, 4c drive wheels 4d rear steered wheels (rear wheels) 5 swing member 6 pivot 16 interlocking mechanism 23 front detection means (detection means) 25 guide member

Claims (2)

[Claims] 1. An automatic guided vehicle in which wheels are provided at positions corresponding to four vertexes of a rhombus in plan view, and one diagonal of the rhombus is set in the front-rear direction of the vehicle, and is located on the one diagonal. The front wheels and the rear wheels are used as steering wheels, and these steering wheels are connected via an interlocking mechanism that interlocks the steering angles with respect to the one diagonal line so that the front wheels and the rear wheels have the same value in opposite directions. The two wheels located on the other diagonal between the front and rear wheels are drive wheels, and the front wheel and the drive wheels are supported by a rocking member, and the rocking member is unmanned at a position between the front wheels and the drive wheels. An unmanned guided vehicle characterized by being pivotally supported by a pivot set toward the vehicle side of the guided vehicle and swingably supported on the vehicle body. 2. The automatic guided vehicle according to claim 1, further comprising means for detecting a guide member installed on a road surface at a front portion of the automatic guided vehicle, wherein the detecting means is provided on a swing member located forward of the front wheel. An automatic guided vehicle characterized by being mounted.