JPH10338127A - Automated guided vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress tilting of a vehicle body caused by loads unevenly loaded on a load carrying face. SOLUTION: An automated guided vehicle 1 provided with two dirigible road wheels 4, 5 and one driven wheel 6 is provided with auxiliary casters 7a, 7b. When a body 2 is tilted around a line S (T) connecting the respective grounding points of one dirigible road wheel 4 (5) and the driven wheel 6 on a travel face, as a rotation axis, and the body 2 inclines in the levitated state of the other dirigible road wheel 5 (4), the auxiliary caster 7a (7b) energizes the travel face on the opposite side to the dirigible road wheel 5 (4) levitated in relation to the rotation axis so as to apply force in the direction of regulating further tilting of the body 2. The auxiliary casters 7a, 7b are supported in such a way as to be vertically movable in a specified range and energized downward by springs. The auxiliary casters 7a, 7b are so constituted that the force energizing the travel face becomes larger as the body 2 is tilted, and supported in such a way as to come in contact with the travel face in the uninclined state of the 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 An automatic guided vehicle is provided with a driving steering wheel and a driven wheel below a substantially rectangular parallelepiped vehicle body having a rectangular loading surface, and the steering direction and the driving direction of the driving steering wheel are controlled. Travel by. FIG. 7 is a schematic plan view showing an example of the automatic guided vehicle 30. The automatic guided vehicle 30 has a traveling wheel disposed at each corner of a rectangular shape substantially similar to the loading surface 31. In the automatic guided vehicle 30, two traveling wheels disposed on one side in the width direction of the vehicle body 32 are drive steering wheels 33 and 34, and two traveling wheels similarly disposed on the other side are driven wheels 35 and 36.

In general, the vehicle body 32 of the transport vehicle 30 is stabilized when the center of gravity of the load is within a posture stability area α formed by connecting the running wheels. In the above-described transport vehicle 30, since the rectangular posture stable area α formed by connecting the respective running wheels substantially coincides with the loading surface 31, even if the load is loaded on the loading surface 31 in a state of being biased, the center of gravity is in the posture. Will be in the stable region α. Therefore, even if the load is loaded on the loading surface 31 in a state of being biased, the transport vehicle 30 is stable.

[0004] However, the automatic guided vehicle 30 traveling on four traveling wheels as described above has a disadvantage that the traveling surface is not flat when the traveling surface is not flat.
One of the two running wheels easily floats from the running surface. When the traveling wheel is the drive steering wheel 33 (34), there is a problem that the traveling state becomes unstable.

To solve such a problem, the automatic guided vehicle 40 shown in FIG. 8 has three running wheels.
That is, drive steering wheels 42 and 43 are provided at both ends in the longitudinal direction on one side in the width direction of the vehicle body 41, and one driven wheel 44 is provided substantially at the center in the longitudinal direction on the other side in the width direction. Even when the traveling surface of the automatic guided vehicle 40 is not flat, the traveling state is stable because the three traveling wheels surely contact the ground.

[0006]

However, three wheels are required.
The automatic guided vehicle 40 has a triangular posture stable region β formed by connecting three traveling wheels, and has a square loading surface 4.
5, the area on the loading surface 45 that does not fall within the posture stable area β increases. For this reason, if the load is loaded on the loading surface 45 in a state of being biased, there is a high possibility that the center of gravity of the load deviates from the posture stable area β.

As described above, the center of gravity of the cargo is in the posture stable area β.
When the vehicle 41 is deviated from the vehicle, the vehicle body 41 is connected to any two of the three running wheels by acceleration applied to the load during acceleration or stoppage, or by acceleration applied to the load while running on an uneven running surface. The line connecting the points may be tilted about the rotation axis, and the remaining one running wheel may be floated. For this reason, pitching may occur in the running vehicle body, and the running state may become unstable. Then, when the degree of pitching becomes severe, there is a problem that the loading state of the load becomes unstable.

In the automatic guided vehicle 40 having a three-wheel configuration, when the load is transferred from the conveyor or the like to the automatic guided vehicle 40, the load is loaded with the center of gravity of the load deviating from the triangular posture stable area β. When the vehicle body 41 is lifted, the vehicle body 41 easily leans temporarily with one traveling wheel floating. For this reason, the loading surface 45 may not be maintained in a horizontal state, and it may be difficult to transfer the load.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an automatic guided vehicle traveling on three traveling wheels, in which a load is loaded in a state where the load is biased on a loading surface. The object of the present invention is to suppress the tilting of the vehicle body due to the fact.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the invention according to claim 1 is directed to an automatic guided vehicle running on three running wheels which are immovably supported in a vertical direction with respect to a vehicle body. In the above, the vehicle body is provided with a tilt restraint means for controlling the tilt of the vehicle body by touching the running surface outside a triangle formed by connecting the respective ground points where the three running wheels touch the running surface. .

According to a second aspect of the present invention, in the first aspect of the present invention, the traveling wheels have two driving steering wheels whose steering directions and driving directions are independently controlled, and a driven direction is fixed. The two driven wheels are arranged along the longitudinal direction on one side in the width direction of the vehicle body, and the driven wheels are arranged on the other side in the width direction of the vehicle body. The tilt control means is provided at substantially the apex of an isosceles triangle having a line connecting the drive steering wheels as a base, and the tilt suppressing means is provided on the front and rear sides of the driven wheel on the other side in the width direction of the vehicle body.

According to a third aspect of the present invention, in the first or second aspect of the invention, the tilt suppressing means includes a caster portion biased to a running surface in a state where the vehicle body is not tilted; A support portion for supporting the caster portion movably in the vertical direction with respect to the vehicle body, and an urging means for urging the caster portion downward with respect to the support portion.

According to a fourth aspect of the present invention, there is provided an automatic guided vehicle which travels on three traveling wheels which are immovably supported in a vertical direction with respect to a vehicle body.
Tilt restricting means is provided for restricting the tilt of the vehicle body by contacting the running surface outside the triangle formed by connecting each of the running wheels to the ground contacting the running surface. (Function) According to the first aspect of the present invention, when the load is transferred in a stopped state, the load is placed in an uneven state, or when the load is loaded in an uneven position, the vehicle starts or stops, etc. Due to the acceleration applied to the vehicle body and the like, the vehicle body uses, as a rotation axis, a line connecting each ground contact point of two of the three running wheels on a running surface as a rotation axis, and the remaining one of the three running wheels When the two running wheels are tilted so as to float, the tilting of the vehicle body is suppressed by the tilting suppression means for suppressing the tilting of the vehicle body by touching the running surface outside the triangle connecting the ground points of the three running wheels.

According to the invention described in claim 2, according to claim 1,
In addition to the operation of the invention described in the above, since the drive steering wheels whose steering direction and drive direction are independently controlled in the longitudinal direction of the vehicle body are arranged, the steering wheels are arranged on one side in the longitudinal direction of the vehicle body. The vehicle can be turned with a smaller turning radius than that of the arranged vehicle.

According to the invention described in claim 3, according to claim 1 of the present invention,
Alternatively, in addition to the function of the invention described in claim 2, when the vehicle body is not tilted, the caster portion supported by the vehicle body at the support portion and urged downward by the urging means rolls on the running surface.
When the vehicle body tilts, the caster portion is more strongly urged against the running surface as the tilt amount increases. Therefore, when the vehicle body tilts, the tilting is suppressed with a stronger force as the tilt amount increases.

According to the fourth aspect of the present invention, even when the load is biased on the loading surface in the stopped state, the load is applied to the traveling surface outside the triangle connecting the ground points of the three traveling wheels. Tilt of the vehicle body is suppressed by a tilt restricting means for restricting the tilt of the vehicle body by touching the ground. Therefore, the vehicle body turns with the line connecting the ground points of the two running wheels of the three running wheels on the running surface as the rotation axis, and the remaining one of the three running wheels travels. Do not tilt so that the wheel floats.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) A first embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a schematic bottom view of the automatic guided vehicle 1. In the automatic guided vehicle 1, the vehicle body 2 is formed in a substantially rectangular parallelepiped shape. The transport vehicle 1 is provided with a rectangular loading surface 3 formed on the upper surface thereof so as to be substantially full in the longitudinal direction and the width direction of the vehicle body 2.

The vehicle body 2 is provided with three running wheels. Two of the three running wheels are driven steering wheels 4,
5 is provided near one corner of the vehicle body 2 on one side in the width direction of the vehicle body 2. The other traveling wheel is a driven wheel 6, which is also provided on the other side in the width direction at the apex of an isosceles triangle whose base is a line connecting the two drive steering wheels 4 and 5.

Each of the drive steered wheels 4 and 5 has a drive motor 4a and 5a, respectively, and a steering mechanism (not shown), so that the drive and the steering are independently controlled. Each of the drive steered wheels 4 and 5 is supported so as not to be able to move in the vertical direction.

The driven wheel 6 is a caster having two wheels, and is supported so as not to move in the vertical direction.
On the side where the driven wheels 6 in the width direction of the vehicle body 2 are provided, the vehicle body 2
Auxiliary casters 7a and 7b are provided near each of the corners as tilt suppressing means. Auxiliary caster 7
a and 7b, as shown in FIG. 2, a support portion 8 fixed to the vehicle body 2 and a caster portion 9 supported by the support portion 8 so as to be movable within a predetermined distance in the vertical direction with respect to the vehicle body 2. Have. A spring as urging means (not shown) is provided in the support portion 8, and the caster portion 9 is urged downward with respect to the support portion 8 by the spring. Each of the auxiliary casters 7a and 7b is provided such that each caster portion 9 urges the running surface R in a state where the carrier 1 is not tilted. When the body 2 tilts and the caster portion 9 compresses the spring and moves upward with respect to the support portion 8, the spring exerts a reaction force applied to the caster portion 9 to tilt the body 2 in the running state and the loaded state. It is formed so that it can be suppressed to the extent that no trouble is caused.

A drive control device (not shown) is provided inside the vehicle body 2. The drive control device controls each of the drive mechanisms and the steering mechanism according to a radio signal transmitted from a guide line (not shown) embedded in the travel surface R, and causes the transport vehicle 1 to travel along the guide line.

Next, the operation of the automatic guided vehicle 1 configured as described above will be described. When the two drive steering wheels 4 and 5 are driven in the same direction while being steered in the longitudinal direction of the vehicle body 2, the carrier 1 travels in the longitudinal direction. 2
When the two drive steering wheels 4 and 5 are driven in the same direction while being steered in the width direction of the vehicle body 2, the carrier 1 travels in the width direction. Further, when the two drive steering wheels are driven in the same direction while being steered in parallel to the oblique direction of the vehicle body 2,
The carrier 1 travels in an oblique direction. When the two drive steering wheels 4 and 5 are driven in opposite directions while being steered in the width direction of the vehicle body 2, the carrier 1 changes its direction on the spot. In each case, each auxiliary caster 7a, 7
The caster part 9 b moves along the running surface R and follows the direction in which the carrier 1 moves.

While the transport vehicle 1 is stopped and the load is being transferred to the loading surface 3 thereof, the center of gravity G of the load connects the respective drive steering wheels 4 and 5 and the driven wheels 6 as shown in FIG. Is deviated from the triangular posture stability area α formed by the following formula, the vehicle body 2 tilts with the line S connecting the ground points of the drive steered wheels 4 and the driven wheels 6 on the running surface as the rotation axis, and the drive steered wheels 5 Suppose that it is tilted in a floating state. Then, as the vehicle body 2 tilts, the auxiliary casters 7a are strongly urged by the running surface R. Therefore, since a force in the direction of restricting the tilt is applied to the vehicle body 2 from the auxiliary caster 7a, the tilt is suppressed. At this time, since the force applied to the vehicle body 2 from the auxiliary casters 7a gradually increases, no impact is applied to the vehicle body 2.

In a state in which the cargo is loaded on the loading surface 3 in an uneven state, the transport vehicle 1 starts moving from a stopped state, stops from a traveling state, or has a non-flat traveling surface R.
When the vehicle 2 travels, the vehicle body 2 receives, for example, a line T connecting the ground points of the drive steering wheels 5 and the driven wheels 6 by the acceleration applied to the load loaded in a state of being biased on the loading surface 3 as a rotation axis. It is assumed that one drive steering wheel 4 has tilted so as to float from the running surface R. Then, as the vehicle body 2 tilts, the auxiliary casters 7b on the drive steered wheels 5 side are urged toward the running surface R.
At this time, the auxiliary casters 7b are gradually urged to the running surface R with a larger force by the action of the spring.
Accordingly, since a force in the direction of suppressing the tilt is applied to the vehicle body 2 from the auxiliary caster 7b, the inclination of the tilt of the vehicle body 2 is suppressed. At this time, since the force applied to the vehicle body 2 from the auxiliary casters 7b gradually increases,
No impact is applied.

Further, even if the vehicle body 2 is pitched by running on the uneven running surface R and the two drive steering wheels 4 and 5 are alternately floated, the tilting for each time is suppressed, and Since no impact is applied to the vehicle body 2, the vehicle body 2 does not pitch greatly.

As described in detail above, according to the automatic guided vehicle 1 of the present embodiment, the following effects can be obtained. (A) Three running wheels (drive steering wheels 4, 5 and driven wheels 6)
In the automatic guided vehicle 1 that travels on the ground, the tilting restraint means (the auxiliary caster 7) that touches the running surface outside the triangle formed by connecting the grounding points of the three running wheels to suppress the tilting of the vehicle body
a, 7b).

Therefore, the vehicle body turns around a line connecting the ground points of any two of the three running wheels on the running surface as a rotation axis, and the remaining three of the three running wheels are rotated. The tilt of one of the running wheels so as to float is suppressed. As a result, when the load is shifted in the stopped state, the load is placed in a biased state, or when the load is loaded in a biased position, the vehicle 2 is caused by acceleration applied to the vehicle body when starting or stopping. Is suppressed. For this reason, at the time of transfer in a stopped state, the loading surface 3 is maintained in a substantially horizontal state, so that the transfer becomes easy. In addition, since the time during which the traveling wheels do not touch the ground during traveling is reduced, the traveling state is stabilized.

(B) When the vehicle body 2 tilts, the caster portion 9 is urged to the running surface R with a larger force as the amount of tilt increases, so that the tilt of the vehicle body 2 is suppressed with a larger force as the tilt amount increases. Is done. As a result, the tilting is suppressed without applying an impact to the vehicle body 2. For this reason, at the time of transfer in the stopped state, the loading surface 3 is maintained in a more horizontal state. Further, during traveling, the traveling state and the loaded state are further stabilized, and the unevenness of the traveling surface R is reduced by the auxiliary casters 7a,
7b, the traveling performance is improved.

(C) Two driving steering wheels 4, 5 are provided on one side in the width direction of the vehicle body 2, and a line connecting the two driving steering wheels 4, 5 on the other side in the same width direction is defined as a base. The test was carried out on the carrier 1 provided with the driven wheels 6 at the vertices of an isosceles triangle. Therefore, it is possible to turn with a smaller turning radius than the carrier provided with the drive steering wheels only on one side in the longitudinal direction of the vehicle body 2.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. This embodiment is different from the first embodiment in that, instead of the auxiliary casters 7a and 7b for limiting the tilting of the vehicle body 2 during running and stopping, the hydraulic cylinder 10 for restricting the tilting of the vehicle body 2 during stopping is used. The first embodiment differs from the first embodiment only in that the first embodiment and the support portion 12 are provided. Therefore, the description of the other same components is omitted by designating the same reference numerals.

FIG. 3 is a schematic bottom view of the automatic guided vehicle 1. As shown in FIG.
5 and the outside of the driven wheel 6, at the four corners of the vehicle body 2,
Hydraulic cylinders 10 are provided as tilt control means. Each hydraulic cylinder 10 includes a rod 11 that extends or retracts with a predetermined stroke. At the tip of the rod 11, a support portion 12 having a larger sectional area than the rod 11 is fixed. Each hydraulic cylinder 1
Numeral 0 is provided so that the rod 11 extends downward, and the support portion 12 comes into contact with the running surface R when the rod 11 extends downward.

Further, a hydraulic pump, an oil tank, a direction control valve, and the like (not shown) are provided inside the vehicle body 2. Further, a cylinder control device (not shown) is provided inside the vehicle body 2. The cylinder control device drives the hydraulic pump and, when stopped for transfer, drives and controls the direction control valve to extend the rod 11 of each hydraulic cylinder 10 to the lowermost end. In addition, the cylinder control device is configured to drive control the direction control valve when the transfer vehicle 1 completes the transfer so that the rod 11 of each hydraulic cylinder 10 is immersed to the uppermost end.

Next, the operation of the automatic guided vehicle 1 configured as described above will be described. When the transport vehicle 1 stops for transfer, each hydraulic cylinder 10 is drive-controlled by the cylinder control device, and the rod 11 is extended to the lowermost end.
Therefore, since the support portion 12 of each rod 11 comes into contact with the running surface R, the vehicle body 2 is supported by both the drive steering wheels 4 and 5 and the driven wheel 6 and supported by each rod 11.

In this state, while the load is being loaded on the loading surface 3, the center of gravity G deviates from the triangular posture stable area α formed by connecting the two driving steering wheels 4, 5 and the driven wheel 6. Also, since the vehicle body 2 is supported by the rod 11, the line S (t) connecting the ground points of the drive steered wheels 4 and the driven wheels 6
(The tilting of the vehicle body 2 about (the rotation axis) is restricted.

When the transfer of the cargo to the carrier 1 is completed,
The drive of each hydraulic cylinder 10 is again controlled by the cylinder control device, and the rod 11 is retracted to the uppermost end. Accordingly, the transport vehicle 1 is supported by only the two driving steering wheels 4 and 5 and the driven wheel 6 and can travel.

As described in detail above, according to the automatic guided vehicle 1 of the present embodiment, the following effects can be obtained. (A) Three running wheels (drive steering wheels 4, 5 and driven wheels 6)
Tilting control means (hydraulic cylinder 10) for controlling the tilting of the vehicle body by contacting the running surface outside the triangle formed by connecting the grounding points of the three running wheels in the stopped state in the automatic guided vehicle 1 traveling at Was provided.

Therefore, in the stopped state, the vehicle body turns around the line connecting the ground points of any two of the three running wheels on the running surface as the rotation axis, and the three running wheels rotate. Is restricted so that the remaining one of the running wheels floats. As a result, the tilt of the vehicle body 2 is restricted even if the load is placed at an uneven position on the loading surface 3 during the transfer in the stopped state. For this reason, the loading surface 3 is maintained in a horizontal state,
Transfer becomes easy.

(B) The vehicle body 2 is supported by the hydraulic cylinder 10 so as not to tilt. Therefore, since a larger force can be obtained than the electric cylinder or the pneumatic cylinder, the support of the vehicle body 2 can be quickly and reliably performed.

The above embodiments may be modified and implemented as follows. The vehicle is not limited to the vehicle 1 having the wheel arrangement like the automatic guided vehicle 1 of the above-described embodiment. For example, as shown in FIG.
One side in the longitudinal direction of the vehicle body 2 is provided with a drive steering wheel 11 at the center in the width direction, and the other side in the longitudinal direction is also provided with driven wheels 12a and 12b fixed to both sides in the width direction. The present invention may be applied to the carrier 1 having wheels. In this case, for example, auxiliary casters 7a and 7b are provided on both sides in the width direction substantially at the center of the vehicle body 2 in the longitudinal direction.

As shown in FIG. 5 (b), a driven wheel 13 is provided on one side in the longitudinal direction of the vehicle body 2 at the center in the width direction, and on the other side in the longitudinal direction also in the width direction. May be applied to the carrier 1 having wheels arranged on both sides of the steering wheel 14a, 14b. In this case, for example,
Auxiliary casters 7a and 7b are provided at substantially the center in the longitudinal direction of the vehicle body 2 on both sides in the width direction.

As shown in FIG. 6A, one side of the vehicle body 2 in the longitudinal direction is provided with a drive steering wheel 1 at the center in the width direction.
5 may be provided on the other side of the longitudinal direction, and the drive steering wheel 16a, 16b may be provided on both sides in the width direction. In this case, for example, auxiliary casters 7a and 7b are provided at substantially the center in the longitudinal direction of the vehicle body 2 on both sides in the width direction.

As shown in FIG. 6B, one side of the vehicle body 2 in the width direction is provided with a drive steering wheel 1 at the center in the longitudinal direction.
7 may be provided on the other side of the width direction, and the steering wheel 18a, 18b may be provided on both sides in the longitudinal direction thereof. In this case, for example, auxiliary casters 7a and 7b are provided on one side in the width direction of the vehicle body 2 on both sides in the longitudinal direction.

According to each of such configurations, in the automatic guided vehicle 1 provided with the respective wheel arrangements, the tilting of the vehicle body 2 at the time of stopping and traveling is suppressed. In the first embodiment, the tilt suppressing means (auxiliary casters 7a, 7b) may be supported so as not to abut on the running surface R when the vehicle body 2 is not tilted. Even with this configuration, the tilting can be suppressed without giving an impact to the vehicle body 2, so that the running state and the loaded state can be stabilized.

In this case, the tilt suppressing means may not include the caster portion 9 which comes into contact with the running surface R. Further, the tilt suppressing means (auxiliary casters 7a, 7b) may be of a fixed type that cannot move in the vertical direction, and may be provided so as not to contact the running surface R when the vehicle body 2 is not tilted. Also with this configuration, since the tilting of the vehicle body 2 can be suppressed, the running state and the loaded state can be stabilized.

The urging means is not limited to a spring, but may be an elastic material such as natural rubber, synthetic rubber, or elastomer, or a pneumatic cylinder. The tilting restricting means may be any device that supports the vehicle body 2 so that the vehicle body 2 does not tilt by contacting the running surface R when stopped, and operates so as not to contact the running surface R during running. Alternatively, a pneumatic cylinder may be used.

Further, an electric cylinder may be used. In this case, since there is no need to mount devices such as a pump and a control valve, a simple configuration can be achieved. ○ The tilt restricting means is provided at a position where the vehicle body 2 does not tilt in a state where the remaining one of the traveling wheels is lifted with a line connecting each ground contact point of any two of the three traveling wheels as a rotation axis. In the transport vehicle 1 of the second embodiment, for example, a configuration in which the driven wheels 6 are provided on the side of the vehicle body 2 where the driven wheels 6 are provided in the width direction may be provided. Good.

The shape of the loading surface 3 is not limited to a rectangle,
In addition, the shape may be a polygon such as a square or a triangle, or a shape such as a circle or an ellipse. Further, in each case, the configuration may be such that the wheels are not arranged below the loading surface.
In each case, the posture of the vehicle can be maintained in a stable state.

Hereinafter, in addition to the technical idea described in the claims, the technical idea grasped from each of the above embodiments will be described together with its effects. (1) In the automatic guided vehicle according to claim 1 or 2, the tilt suppressing means is configured to more strongly suppress the tilt as the vehicle body tilts. According to such a configuration, the tilting can be suppressed without giving an impact to the vehicle body, so that the running state and the loaded state can be further stabilized.

(2) In the automatic guided vehicle according to the fourth aspect, the tilt regulating means is extended so as to abut on the running surface when stopped, and is immersed so as not to come into contact with the running surface during running. Hydraulic cylinder. According to such a configuration, a greater force can be obtained than with an electric cylinder or a pneumatic cylinder, so that even when the load of the load is large, the tilting of the vehicle body can be reliably restricted.

In this specification, means and members according to the present invention are defined as follows. (1) The traveling wheels may be any wheels that can support and move the vehicle body in a state in which the traveling wheels are not movable in the vertical direction with respect to the vehicle body. Fixed direction drive wheels, steered driven wheels,
It includes a driven wheel whose direction is not fixed and a driven wheel whose direction is fixed.

[0052]

According to the first to third aspects of the present invention, in an automatic guided vehicle traveling on three traveling wheels, the body of the vehicle due to the fact that the cargo is loaded on the loading surface in an uneven state is considered. Tilt can be suppressed.

According to the second aspect of the present invention, it is possible to turn with a smaller turning radius than a vehicle in which the steered wheels are arranged on one side in the longitudinal direction of the vehicle body. According to the third aspect of the invention, the tilting can be suppressed without giving an impact to the vehicle body.

According to the fourth aspect of the present invention, the transfer surface can be maintained in a horizontal state at the time of transfer in the stopped state, so that transfer can be facilitated.

[Brief description of the drawings]

FIG. 1 is a schematic bottom view of an automatic guided vehicle according to a first embodiment.

FIG. 2 is a schematic perspective view of a caster.

FIG. 3 is a schematic bottom view of the automatic guided vehicle according to the second embodiment.

FIG. 4 is a longitudinal sectional view of the automatic guided vehicle.

5 (a) and 5 (b) are schematic bottom views of another example of an automatic guided vehicle.

6 (a) and 6 (b) are schematic bottom views of another example of an automatic guided vehicle.

FIG. 7 is a schematic bottom view of a conventional automatic guided vehicle.

FIG. 8 is a schematic bottom view.

[Explanation of symbols]

Reference numeral 2 denotes a vehicle body, 4 denotes a driven steering wheel as a wheel, 5 denotes a driven steering wheel, 6 denotes a driven wheel, 7a and 7b denotes an auxiliary caster as a tilt suppressing means, 9 denotes a caster portion, and 10 denotes a tilt regulating means. Hydraulic cylinder, R: running surface, S, T ...
line.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G05D 1/02 G05D 1/02 R

Claims (4)

[Claims] 1. An automatic guided vehicle that travels on three traveling wheels that are supported immovably in a vertical direction with respect to a vehicle body, wherein each of the vehicle bodies has a contact point where the three traveling wheels contact a traveling surface. An automatic guided vehicle provided with a tilt restraint means for grounding the running surface outside a triangle formed by connecting the tilted wheels to suppress tilting of the vehicle body. 2. The automatic guided vehicle according to claim 1, wherein the traveling wheels include two driving steering wheels whose steering directions and driving directions are independently controlled, and one traveling wheel whose driven directions are not fixed. The driven wheels are arranged along the longitudinal direction on one side in the width direction of the vehicle body, and the driven wheels connect the driven wheels on the other side in the width direction of the vehicle body. An automatic guided vehicle provided substantially at the apex of an isosceles triangle having a line as a base, and the tilting suppressing means provided on both the front and rear sides of the driven wheel on the other side in the width direction of the vehicle body. 3. The automatic guided vehicle according to claim 1, wherein the tilt suppressing means includes: a caster portion that is urged to a running surface in a state where the vehicle body is not tilted; An automatic guided vehicle comprising: a support portion that supports the vehicle body so as to be movable in a vertical direction; and urging means that urges the caster portion downward with respect to the support portion. 4. An automatic guided vehicle traveling on three traveling wheels supported immovably in a vertical direction with respect to a vehicle body, wherein each of the three traveling wheels comes into contact with a traveling surface when the vehicle body is stopped. An automatic guided vehicle provided with a tilt restricting means for restricting the tilt of the vehicle body by contacting the running surface outside a triangle formed by connecting a ground point.