JP2002284499A - Commodity carrier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a commodity carrier capable of accurately travelling to a cargo delivery position in a station even in the case of the bad conditions of a floor. SOLUTION: Guide sensors 14, 45 are provided on the front and rear parts of a body 1 at its crosswise centers for detecting the crosswise displacement of the body from an auxiliary guide line K. When the body 1 is turned from a main guide line L to the auxiliary guide line K, an inclination θ between the crosswise center of the body 1 and the center of the auxiliary guide line K is found from the displacements of the front and rear parts of the body detected by the guide sensors 14, 45. A turning angle of driving wheels of the body 1 is found from the inclination θ and a predetermined corrected moving distance on the auxiliary guide line L. This construction permits corrected moving distance travel at the turning angle while correcting the inclination of the body 1, the arrival of the body at a position in the station with correct attitude and normal cargo delivery with forks 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an article carrier equipped with a fork.

[0002]

2. Description of the Related Art As the article transport vehicle, a pair of left and right driven wheels provided in the front-rear direction of the vehicle body to support the load of the vehicle body, supporting the load of the vehicle body and running the vehicle body. A drive wheel provided closer to one side in the vehicle longitudinal direction than the driven wheel, and configured to be able to move back and forth along the vehicle longitudinal direction to transfer a load on the other side in the vehicle longitudinal direction. 2. Description of the Related Art There is known an article transport vehicle including a fork, wherein the drive wheel is configured to be rotatable around a vertical axis along a vertical direction in order to steer a vehicle body.

[0003] Such an article transport vehicle is used for transporting various articles in a warehouse or a factory. As shown in FIG. 15, an article transport vehicle V is mainly a guide line installed on a floor R. When the vehicle automatically travels along the travel path formed by L and arrives at the station ST installed along the guide line L, the drive wheel is rotated by 90 degrees about the longitudinal axis to perform an in-situ turn (spin A turn is performed), and the vehicle moves backward to transfer the load A to and from the station ST using the fork.

[0004]

However, in the above-mentioned article transport vehicle, when the spin turn is performed, since the vehicle is simply moved straight backward, the rotation accuracy of the spin turn cannot be maintained due to the condition of the floor R and the like. In some cases, the delivery position of the load A at the station ST may be greatly deviated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an article transport vehicle that can accurately travel to a load transfer position of a station even when the floor condition is poor.

[0006]

In order to achieve the above-mentioned object, a first aspect of the present invention is a pair of right and left driven members provided at an intermediate position in the front-rear direction of the vehicle body to support a load of the vehicle body. Wheels, drive wheels provided to support the load of the vehicle body, and provided at a position closer to one side in the vehicle longitudinal direction than the driven wheels for running the vehicle body, and load is transferred to the other side in the vehicle longitudinal direction. And a fork configured to be able to move back and forth along the front-rear direction of the vehicle body so that the drive wheel is configured to be rotatable around a vertical axis along a vertical direction in order to steer the vehicle body, A main guide line arranged on the surface, an article transport vehicle traveling along a sub-guide line further intersecting the main guide line, at the center in the left-right direction of the vehicle body, and at the front and rear of the vehicle body, The main or secondary guidance line A shift amount detecting means for detecting a shift amount in the lateral direction of the vehicle body from the vehicle, the drive wheel is rotated around the vertical axis and driven to travel, and when the main guide line is turned to the auxiliary guide line, The center of the vehicle body in the left-right direction and the inclination of the sub-guide line are obtained from the respective deviation amounts of the front part and the rear part of the vehicle body detected by the deviation amount detection means. It is characterized in that a turning angle of a driving wheel is obtained.

Here, the main guide line and the sub guide line are
For example, it is constituted by a belt-like guide having magnetism, and the deviation amount detecting means is constituted by a plurality of magnetic sensors installed in a lateral direction for detecting the magnetism of the guide line.

[0008] According to the above configuration, when the article transport vehicle travels along the main guide line and changes direction to the sub guide line, the difference between the front and rear vehicle body detected by the shift detecting means is used. The inclination between the center of the vehicle body in the left-right direction and the center of the auxiliary guidance line is obtained, and the turning angle of the drive wheel is obtained based on this inclination and a predetermined corrected moving distance on the auxiliary guidance line. When the vehicle travels at the predetermined correction moving distance at this turning angle, the center of the vehicle body in the left-right direction matches the center of the sub-guide line, and the inclination is corrected.

According to a second aspect of the present invention, in the first aspect of the present invention, a plurality of sub-guide lines are provided so as to intersect with the main guide line, and the corrected travel distance is determined by the travel distance of the sub-guide. It is characterized by being selected by line.

[0010] The distance between the sub-guide lines, that is, the distance between the sub-guide lines connecting the main guide line and the stations, differs depending on the arrangement of the stations. According to the above configuration, the correction moving distance is selected according to (the distance of) the traveling auxiliary guidance line, and the turning angle of the drive wheel for correcting the inclination is set.

According to a third aspect of the present invention, in the first or second aspect of the present invention, if the inclination of the sub-guide line with the center of the vehicle body in the left-right direction is larger than a predetermined inclination, derailment occurs. And stopping the traveling.

According to the above construction, if the inclination between the center of the vehicle body in the left-right direction and the center of the auxiliary guidance line is larger than a predetermined inclination, the driving wheel for correcting this inclination is moved even if the turning angle is determined. It is determined that it is impossible to match the center of the vehicle body in the left-right direction with the center of the auxiliary guidance line.

The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein a driving wheel is provided at a central portion of the vehicle body in the left-right direction, and the driving wheel is provided. It is characterized by comprising a pair of drive wheels that can be driven forward and reverse respectively.

According to the above construction, the drive wheels are provided at the center in the left-right direction of the vehicle body, so that when the vehicle body is turned around the driven wheel side, the vehicle is turned with a relatively small radius in both the right and left directions. Can be turned well, and
By forming the drive wheels from a pair of drive wheels that can be driven forward and reverse, respectively, the pair of drive wheels can be rotated at different speeds, or by rotating in opposite directions. The driving wheel composed of a wheel can be rotated around the vertical axis, and the rotational driving of the driving wheel and the rotating operation around the vertical axis can be shared by the same drive source.

The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the vehicle body is formed by a pair of left and right extending portions along the front-rear direction of the vehicle body, and And a main body portion connected to one side in the front-rear direction of the vehicle body, and have a substantially U-shape in plan view, the main body portion is provided with the driving wheels, and a tip side of the pair of left and right extending portions. Are provided with idle wheels, and when the fork is retired, the tip of the fork is located inside the tip of the extending portion.

According to the above configuration, the vehicle body of the carrier is constituted by a pair of left and right extending portions along the vehicle longitudinal direction, and a main body portion connecting the extending portions on one side in the vehicle longitudinal direction,
In a substantially U-shape in plan view, a drive wheel is provided on the main body portion, and an idle wheel is provided on a tip side of the pair of left and right extending portions, so that when loading and transferring the load by moving the fork out and back. The idler wheels provided at the leading end of the left and right extending portions can reliably and stably hold the vehicle body, and even when the fork is configured to be able to move up and down, at the intermediate portion between the left and right extending portions. By raising and lowering the fork, the fork can be lowered close to the traveling road surface of the transport vehicle. In addition, the tip of the fork is configured such that the tip of the fork is located inside the tip of the extending portion when the fork is retired. There is little possibility of contact, and it is possible to drive safely.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a main part of a factory using an article carrier according to an embodiment of the present invention. A main guide line L constituted by a magnetic belt-shaped guide is arranged on a floor (floor surface) R. And the main guidance line L
Guides the article transport vehicle V to each station ST
A plurality of sub-guide lines K configured by magnetic belt-like guides are arranged. The article transport vehicle V of the present invention includes:
The vehicle automatically travels mainly along a travel path formed by the guide line L, travels to stations along the sub-guide line K, and carries the load A between the stations ST.

As shown in FIG. 2, the vehicle body 1 of the article transport vehicle V has a pair of left and right extending portions 2 along the front-rear direction of the vehicle body 1.
The extension portion 2 is constituted by a main body portion 3 which is connected to the front side of the vehicle body 1 (an example of one side in the front-rear direction of the vehicle body), and is configured to be substantially U-shaped in plan view. As shown in FIG. 3, a fork 4 protruding rearward of the vehicle body 1 is provided on the vehicle body 1 so as to be able to move back and forth along the front-rear direction of the vehicle body 1 (an example of the other side in the front-rear direction of the vehicle body). In addition, it is provided so as to be able to move up and down in the vertical direction. The rear portion of the vehicle body 1 faces each station ST, and the fork 4 is moved out and up and down to transfer the load A.

As shown in FIGS. 3 and 4, a drive wheel 6 comprising a pair of drive wheels 5 which are spaced apart from each other and juxtaposed, is provided on the bottom of the main body portion 3 located on the front side of the vehicle body 1 in the left-right direction. A pair of left and right idler driven wheels 7 are provided at the bottom of the extended portion 2 of the vehicle body 1 in the front-rear direction, and rotatably provided around a vertical axis P1 along the vertical direction. ing. The drive wheel 6 and the driven wheel 7 are configured to support the load of the vehicle body 1 by three-point support.

As shown in FIGS. 5 to 7, the driving wheels 6 are connected directly to electric motors 8a and 8b, respectively, to the driving wheels 5 constituting the driving wheels 6, and the two driving wheels 5 are connected to each other. Separately, the drive wheels 5 are configured to be able to be driven in normal and reverse rotations, and the rotational speeds of the drive wheels 5 are given a difference, or the drive wheels 5 are driven to rotate in directions opposite to each other, so that the vertical It is configured such that the direction can be changed integrally around the axis P1.

That is, a connecting frame 9 is disposed between the two driving wheels 5, and the connecting frame 9 connects and supports one driving wheel 5 and a motor 8a for driving the driving wheel 5 on one side. On the side, another driving wheel body 5 and a motor 8b for driving it are connected and supported. The connecting frame 9 is located near the lower ends of both drive wheels 5 and
The annular frame 10 is provided rotatably around a horizontal axis P2 along a horizontal direction from a circular frame 10 arranged concentrically with respect to the vertical axis P1 to a vertical frame 11 continuously provided therewith. A frame 10 is attached to the main body 3 of the vehicle body 1 via a bearing 12 so as to be rotatable around a longitudinal axis P1.

A sensor bracket 13 extends from one of the two vertical frames 11, and a first guide sensor (an example of a shift amount detecting means) 14 is attached to the sensor bracket 13, and the first guide sensor 14 is provided. Are located in front of a drive wheel 6 composed of a pair of drive wheels 5, and are located at the left and right centers of the vehicle body 1 and at the front end (front portion) of the vehicle body 1. The first guide sensor 14 is composed of a plurality of magnetic sensors juxtaposed in the lateral direction, and detects the magnetic fields of the main guiding line L and the sub-guiding line K, which are magnetized in the shape of a strip, so that the guiding line of the vehicle body 1 is detected. It is used to detect a displacement between L and the auxiliary guidance line K to control the steering of the vehicle body 1. The main body 3 above the drive wheel 6 has the longitudinal axis P1
The rotary encoder 15 is attached in a state where it is located above, and the rotation shaft 16 of the rotary encoder 15 is
The rotary encoder 15 is attached to a transfer frame 17 that connects the upper portions of the two vertical frames 11, and the rotary encoder 15 determines the direction of the drive wheel 6 turning around the vertical axis P 1, that is, the turning angle (steering angle) of the drive wheel 6. It is configured to detect. The motors 8a and 8b for driving the driving wheels 5 are provided with rotary encoders for detecting the amount of rotation, respectively, and the detection signals are used for calculating the traveling distance information.

As shown in FIG. 4 and FIG.
A caster type idler wheel 19 composed of a pair of idler wheels 18 spaced apart and juxtaposed at the bottom of the distal end of the extension portion 2 on the rear side is turned around a vertical axis Q1 along the vertical direction. A pair of left and right is provided movably. The idler wheel 18 of each idler wheel 19 is rotatably supported by a wheel support frame 20 located between the idler wheels 18, and the wheel support frame 20.
Is mounted on the wheel support bracket 21 so as to be movable up and down around a horizontal axis Q2 along the horizontal direction, and is urged downward by a spring 22. The wheel support bracket 21 is connected and held to an inner race 24 of a bearing 23, and an outer race 25 of the bearing 23 is attached to the extending portion 2 of the vehicle body 1, whereby each idle wheel 19 is attached to the bearing 23.
Is configured to be rotatable around the vertical axis Q1 which is the axis of rotation of.

As described above, each idle wheel 19 is provided with a horizontal axis Q2.
It is configured to be able to move vertically around and is urged downward by the spring 22,
Each idler wheel 19 is provided with a wheel lock means 26 for restricting upward movement around the horizontal axis Q2. The wheel locking means 26 includes a hydraulic cylinder 27 that expands and contracts following the vertical movement of the idler wheel 19, and a valve device that supplies oil in the tank 28 to the hydraulic cylinder 27 or stops oil supply. I have. The hydraulic cylinder 27 is disposed on the axis of the vertical axis Q1.
However, the hydraulic cylinder 27 is pressed and urged to the lower wheel support frame 20 by a spring 30 provided inside, and the cylinder rod 29 moves up and down following the up and down movement of the wheel support frame 20, whereby the hydraulic cylinder 27 is moved. It is configured to expand and contract.

The valve device includes a check valve 32 for preventing oil supply to the variable throttle 31 and the hydraulic cylinder 27;
A check valve 33 for preventing return of oil to the tank 28 when the hydraulic cylinder 27 is shortened, and a switching operation performed by a solenoid 34 to allow supply and discharge of oil to and from the hydraulic cylinder 27 to allow the idle wheel The lock 19 is configured to be switchable between an unlocked state in which the vertical movement of the idle wheel 19 is allowed and a locked state in which the hydraulic cylinder 27 is prevented from being shortened to prevent the idle wheel 19 from moving upward. The locked state and the released state of the wheel locking means 26 are switched in conjunction with the operation of the fork 4. When the fork 4 is moved up and down and the load A is transferred, the locked state is set to the locked state. 4
Is configured to switch to the unlocked state when the load A is conveyed while being retracted. In addition, this valve device
It is configured to switch to the unlocked state by energizing the solenoid 34, and if the battery A mounted on the vehicle body 1 becomes insufficient in power or breaks during transfer of the load A, the spring 35 is used to switch to the unlocked state. It is configured to switch.

As shown in FIGS. 9 and 10, the fork 4 can be moved up and down along a pair of right and left posts 36. The fork 4 can be moved up and down by an electric motor (not shown) via a transmission mechanism such as a chain 37. It is configured to be able to. Further, the post 36 is erected on a trolley 38 configured to be movable in the front-rear direction of the vehicle body 1, and the wheels 39 are rotated forward and reverse by an electric motor (not shown) to thereby rotate the post 36 on the trolley 38. In the fore-and-aft direction of the vehicle body 1, thereby moving the fork 4 in the fore-and-aft direction of the vehicle body 1 so as to protrude rearward from the distal ends of the left and right extending portions 2, or to move inward from the distal ends of the extending portions 2. It is configured to be retired.

When the fork 4 is lowered to the lowest position, the fork 4 enters the space between the left and right extending portions 2 and can be lowered below the upper surfaces of the two extending portions 2. It is configured as follows. That is, the fork 4 is configured to be able to move up and down with respect to the upper surface of the extending portion 2 as a reference, and by moving the fork 4 up and down and up and down with the extending portion 2 side facing each station ST. The load A on the station ST side is transferred to the vehicle body 1 side, and the loading surface 40 which is the upper surface of the extension portion 2 is mounted.
It is configured so that the load A on the load mounting surface 40 can be transferred to the station ST side.

The entire circumference of the lateral portion of the vehicle body 1, that is, from the distal end portion to the outer portion of the pair of left and right extending portions 2, and from the outer portion to the outer portion of the main body portion 3,
As shown in FIGS. 2 and 3, an obstacle buffer bumper 41 made of an elastic member or the like is provided, and a light consisting of a light projector 42 a and a light receiver 42 b is provided between the tips of the left and right extending portions 2. A sensor 42 is provided, and when the optical sensor 42 detects an obstacle, the driving of the driving wheel 6 is stopped.

As shown in FIGS. 4 and 8, the ends of the left and right extending portions 2 are connected by a connecting member 43, and the sensor bracket 44 extends from the center of the connecting member 43 toward the floor R. A second guide sensor (an example of a deviation amount detecting unit) 45 is attached to the sensor bracket 44, and the second guide sensor 45 is located at the left and right centers of the vehicle body 1 and at the rear end (rear portion) of the vehicle body 1. It is configured as follows. Like the first guide sensor 14, the second guide sensor 45 is composed of a plurality of magnetic sensors juxtaposed in the lateral direction, and detects the magnetic fields of the main guiding line L and the sub-guiding line K, which are magnetized in a strip shape. By doing so, the displacement of the vehicle body 1 with respect to the guidance line L and the auxiliary guidance line K is detected and used to control the steering of the vehicle body 1.

In the vehicle body 1, there are provided a controller 51 shown in FIG. 11 and inverters 52a and 52b for controlling the rotation speeds of the motors 8a and 8b. The controller 51 provides the front and rear center positions of the left and right centers of the vehicle body 1 detected by the first guide sensor 14 and the second guide sensor 45, the steering angle detected by the rotary encoder 15, and the motors 8a and 8b. The rotary encoder 53 attached to each
The detected rotation amounts of the motors 8a and 8b are input to the inverters 52a and 52b, and the rotation speed command signals of the motors 8a and 8b are output to the inverters 52a and 52b, respectively. Although not shown, various mark sensors, ID tag readers, and the like are provided on the bottom side of the vehicle body 1, and various types of detection information including the optical sensor 42 are input to the controller 51. A driving signal is output to the electric motor for the fork 4 and the solenoid 34 of the lock mechanism 26, and the traveling control is executed by the controller 51. As shown on the right side of FIG.
The vehicle travels while moving away from the station ST along the sub-guide line K in a reverse state, or away from the station ST in a forward state, as shown on the left side of FIG. Various controls such as transfer of A are also executed, and the operation of the wheel lock means 26 is also controlled.

The traveling control of the vehicle body 1 from the main guide line L to the station ST along the sub guide line K by the controller 51 will be described in detail with reference to the flowchart of FIG.

Step-1 First, an inverter 5 for controlling the left and right motors 8a, 8b
A rotation command in the reverse rotation direction is output to 2a and 52b at the same rotation speed, and when the steering angle detected by the rotary encoder 15 becomes 90 degrees, a stop command is output. Thus, at the same position, the drive wheel 6 rotates from the front-rear direction of the vehicle body 1 to the left-right direction (the direction of the drive wheel 6 changes).

Step-2 Next, in order to rotate the vehicle body 1 to the left, the inverter 52
a and 52b are required to rotate at the same rotational speed and in the same rotational direction (direction for rotating the vehicle body 1 to the left), so that the left and right centers of the vehicle body 1 rotate from the main guide line L to the auxiliary guide line K at the rotational speed. Output for a certain period of time (preset time).
As a result, the vehicle body 1 rotates 90 degrees to the left (spin-turns) from the posture shown in FIG.
That is, the left and right centers of the vehicle body 1 move from the main guide line L to the sub guide line K. At this time, the fork 4
The vehicle body 1 faces rearward so that the vehicle can be delivered.

Step-3 Next, the positional deviations of the front and rear ends of the left and right centers of the vehicle body 1 detected by the first guide sensor 14 and the second guide sensor 45 are confirmed, and the left and right centers of the vehicle body 1 and the secondary guidance are detected. The inclination of the line K (hereinafter, referred to as the vehicle body inclination angle) is detected. As shown in FIG. 13, the first guide sensor 14 and the second
Since the distance J between the guide sensors 45 is constant, the vehicle body tilt angle θ is obtained from the positional deviation at the front end and the positional deviation at the rear end.

Step-4 Next, the inclination of the vehicle body 1 can be corrected from the distance Q (FIG. 1) of the auxiliary guidance line K (the distance the article transport vehicle V moves from the main guidance line L to the station ST). An appropriate correction movement distance is selected from a plurality of preset correction movement distances. For example, if the distance Q to the station ST is 2
000 mm or more, the correction movement distance is 200 mm,
When the distance Q to the station ST is less than 2000 mm, a correction movement distance of 250 mm is selected.

Step-5 Next, the corrected moving distance is moved according to the pre-calculated table shown in FIG. 14 based on the obtained vehicle body inclination angle θ, the selected corrected moving distance, and the predetermined rotation speed of the drive wheel 6. A turning angle (steering angle) α of the driving wheel 6 during the driving is determined. If it is determined that the inclination of the vehicle body 1 cannot be corrected based on the vehicle body inclination angle θ and the selected correction movement distance, it is recognized that the vehicle has derailed, a derailment warning is issued, and the traveling is stopped. If the corrected moving distance is 200 mm and the vehicle body tilt angle θ becomes 2.2 degrees or more, it is determined that the vehicle is derailed, and the corrected moving distance is 250 mm.
When the vehicle body inclination angle θ becomes 2.8 degrees or more, it is determined that the vehicle is derailed.

Step-6 Next, the inverter 5 for controlling the left and right motors 8a, 8b
A rotation command in the reverse rotation direction is output to 2a and 52b at the same rotation speed, and when the steering angle detected by the rotary encoder 15 reaches the calculated turning angle, a stop command is output. Thus, at the same position, the drive wheel 6 rotates to the turning angle α.

Step-7 Next, a rotation command is output to the inverters 52a and 52b in the same rotation direction (direction for moving the vehicle body 1 backward) at the same predetermined rotation speed, and the motor rotation detected by the rotary encoders 53a and 53b. The moving distance of the vehicle body 1 obtained from the number is
When the corrected moving distance is reached, a stop command is output. Thereby, the inclination of the vehicle body 1 is corrected at the time when the vehicle moves backward by the corrected moving distance.

Step-8 Next, the inverter 5 for controlling the left and right motors 8a, 8b
A rotation command in the reverse rotation direction is output to 2a and 52b at the same rotation speed. When the steering angle detected by the rotary encoder 15 becomes 0 degree, a stop command is output. Thus, at the same position, the drive wheel 6 rotates back to 0 degrees and returns.

Step-9 Next, a rotation command is output to the inverters 52a and 52b at the same predetermined rotation speed and in the same rotation direction (direction in which the vehicle body 1 is moved backward), and the motor rotation detected by the rotary encoders 53a and 53b. The moving distance of the vehicle body 1 obtained from the number is
When the distance becomes the value obtained by subtracting the corrected movement distance from the distance from the main guide line L to the station ST, a stop command is output. Thereby, the vehicle body 1 arrives at the station ST in a correct posture. During the reverse travel, the left and right inverters 52a, 52a, 5b feed back the deviation detected by the second guide sensor 45 located forward.
It is also possible to control the number of times of output to 2b to control and turn the vehicle so that the vehicle body 1 moves along the auxiliary guidance line K.

As described above, when the article transporting vehicle V travels along the main guide line L, turns the vehicle body 1 and turns to the sub guide line K, the guide sensors 14 and 4
5, the inclination between the center of the vehicle body 1 in the left-right direction and the center of the auxiliary guidance line K is obtained, and the inclination of the vehicle body 1 is calculated based on the vehicle body inclination angle and the corrected moving distance on the auxiliary guidance line K. The turning angle of the drive wheel 6 that can be corrected is obtained, and when the vehicle travels the corrected moving distance at the turning angle, the center of the vehicle body 1 in the left-right direction matches the center of the auxiliary guidance line K, and the inclination is corrected. Therefore, it is possible to arrive at the station ST in a correct posture, and the fork 4 can normally deliver and receive the load A.

By providing the drive wheel 6 at the center of the vehicle body 1 in the left-right direction, when the vehicle body 1 is turned around the driven wheel 7 side, the turn can be made with a relatively small radius in both the right and left directions. A pair of drive wheels 5 that can be turned and can drive their drive wheels 6 forward and backward separately
By rotating the pair of drive wheels 5 at different speeds from each other, or by rotating the drive wheels 5 in opposite directions, the drive wheels 6 composed of the pair of drive wheels 5
Can be rotated around the vertical axis P1 and the same motors (drive sources) 8a and 8b can be used to rotate the drive wheel 6 and rotate around the vertical axis P1.

The vehicle body 1 of the article transport vehicle V comprises a pair of left and right extending portions 2 extending in the vehicle longitudinal direction, and a main body portion 3 connecting the extending portions 2 on one side in the vehicle longitudinal direction.
In a plan view, the main body 3 is provided with a drive wheel 6 and a pair of left and right extending portions 2 is provided with a freewheel 19 at a tip end thereof, so that the fork 4 is moved out and retreated. At the time of loading, the idler wheels 19 provided on the front end sides of the left and right extending portions 2 can securely and stably hold the vehicle body 1, and even when the fork 4 is configured to be able to move up and down. By moving the fork 4 up and down at the intermediate portion of the extended portion 2 of the vehicle, the fork 4 can be lowered close to the traveling road surface of the article transport vehicle V. In addition, when the fork 4 is retired, the tip of the fork 4 is located inside the tip of the extension portion 2 so that the fork 4 can be retired and run, so that the tip of the fork 4 can be moved. There is little possibility of contact with other objects, and the vehicle can travel safely.

In this embodiment, the main guidance line L
And the auxiliary guidance line K are formed in the shape of a magnetic strip, and the guide sensors 14 and 45, which are shift amount detecting means, are formed by a plurality of magnetic sensors arranged side by side in the horizontal direction. The line L and the sub guide line K may be configured by a strip-shaped reflector, and the guide sensor serving as the shift amount detecting unit may be configured by a plurality of photoelectric switches arranged side by side in the horizontal direction.

Further, in the present embodiment, the main guide line L and the sub guide line K intersect at 90 degrees. However, the present invention is not limited to 90 degrees, and the main guide line L intersects at another angle depending on the position of the station ST. Is also good. At this time, when spinning the vehicle body 1 between the main guide line L and the sub guide line K, the vehicle may be turned at the intersection angle between the main guide line L and the sub guide line K.

In this embodiment, the hydraulic cylinder 27
Although the wheel lock means 26 is constituted by using such means, various changes can be made in actual implementation such as mechanical lock means and electric lock means. Various changes can also be made to the configuration for moving to.

[0047]

As described above, according to the present invention, the center of the vehicle body in the left-right direction and the inclination of the auxiliary guidance line are obtained, and the drive wheels are turned based on the inclination and the predetermined correction moving distance on the auxiliary guidance line. By calculating the angle and running the predetermined corrected movement distance at the turning angle, the center of the vehicle body in the left-right direction and the center of the auxiliary guidance line can be matched, and the inclination of the vehicle body can be corrected.

[Brief description of the drawings]

FIG. 1 is a plan view of a main part of a factory using an article carrier according to an embodiment of the present invention.

FIG. 2 is a plan view of the article transport vehicle.

FIG. 3 is a side view of the article transport vehicle.

FIG. 4 is a plan view showing an arrangement of wheels of the article transport vehicle.

FIG. 5 is a plan view of drive wheels of the article transport vehicle.

FIG. 6 is a front view of drive wheels of the article transport vehicle.

FIG. 7 is a longitudinal sectional side view of drive wheels of the article transport vehicle.

FIG. 8 is a side view of idle wheels of the article transport vehicle.

FIG. 9 is a side view showing the operation of the fork of the article transport vehicle.

FIG. 10 is a side view showing the operation of the fork of the article transport vehicle.

FIG. 11 is a main part control configuration diagram of the article transport vehicle.

FIG. 12 is a flowchart illustrating a traveling control operation performed by a controller of the article transport vehicle.

FIG. 13 is an explanatory diagram of vehicle body inclination detection of the article carrier.

FIG. 14 is an explanatory diagram for obtaining a steering angle from a vehicle body inclination angle of the article transport vehicle.

FIG. 15 is a plan view showing the operation of the article transport vehicle.

[Explanation of symbols]

 V article carrier A load P1 longitudinal axis 1 body 2 extension 3 body 4 fork 5 drive wheel 6 drive wheel 7 driven wheel 8a, 8b motor 14, 45 guide sensor 15 rotary encoder 19 idle wheel 26 wheel lock Means 40 Loading surface 51 Controller 52a, 52b Inverter 53a, 53b Rotary encoder

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // B62D 137: 00 B62D 137: 00 F term (Reference) 3D032 CC20 DA01 DA84 DB11 DB12 DC33 DD02 DD17 DE03 DE09 EB04 EC22 EC34 GG06 GG07 3F022 KK01 LL07 NN32 NN57 QQ03 QQ04 QQ11 3F333 AA02 AB20 FA17 FA20 FD07 FE04 FE05 FE09

Claims (5)

[Claims] 1. A pair of left and right driven wheels provided at an intermediate position in the front-rear direction of the vehicle body to support the load of the vehicle body, and the driven wheels to support the load of the vehicle body and run the vehicle body A drive wheel provided closer to one side of the vehicle body front and rear direction, and a fork configured to be able to move back and forth along the vehicle body front and rear direction to transfer a load on the other side of the vehicle body front and rear direction, The drive wheel is configured to be rotatable around a vertical axis along a vertical direction in order to steer the vehicle body, along a main guide line disposed on the floor surface, and further along a sub-guide line crossing the main guide line. A traveling article carrier, which is a center of the vehicle body in the left-right direction and at a front part and a rear part of the vehicle body, respectively, which detects a deviation amount in the vehicle body left-right direction from the main guide line or the sub-guide line. Means, Wheel is traveling is driven to pivot about a vertical axis,
When the vehicle is turned from the main guide line to the sub guide line, the center of the vehicle body in the left-right direction and the inclination of the sub guide line are obtained from the respective shift amounts of the front and rear portions of the vehicle body detected by the shift amount detecting means. An article transport vehicle, wherein a turning angle of the drive wheel is obtained based on a tilt and a predetermined corrected moving distance on a sub-guide line. 2. The article transport vehicle according to claim 1, wherein a plurality of sub-guide lines are provided so as to intersect with the main guide line, and the correction movement distance is selected by the running sub-guide line. 3. The article according to claim 1, wherein when the inclination of the auxiliary guidance line with respect to the center of the vehicle body in the left-right direction is larger than a predetermined inclination, derailment is determined and traveling is stopped. Transport vehicle. 4. The vehicle according to claim 1, wherein the driving wheels are provided at a central portion of the vehicle body in the left-right direction, and the driving wheels are each constituted by a pair of driving wheels that can be driven forward and reverse independently.
An article carrier according to claim 3. 5. A vehicle body comprising a pair of left and right extending portions extending in the front-rear direction of the vehicle body and a main body portion connecting the extending portions on one side in the front-rear direction of the vehicle body. The drive wheel is provided on the main body portion, and idle wheels are provided on the tip sides of the pair of left and right extending portions, respectively, and when the fork is retired, the tip of the fork is the tip of the extending portion. The article carrier according to any one of claims 1 to 4, wherein the article carrier is configured to be located further inside.