JP3150428B2 - Automatic guided vehicle - Google Patents

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 that tracks a magnetic cable, a magnetic tape, a light reflecting tape, or the like laid on a floor of a machine shop, an assembly shop, or the like, and other guidance methods ( The present invention is effective when applied to an unmanned transport vehicle that travels on a track without using a laser) and that has a fork.

[0002]

2. Description of the Related Art Conventionally, in a machine factory, an assembly factory, and the like, materials, parts, completed products, and the like are transported by transport means such as a conveyor. Tend to adopt. The automatic guided vehicle automatically travels by detecting electromagnetic cables, magnetic tapes, light reflecting tapes, etc. laid on the floor as a traveling route (track) using magnetic detectors and optical detectors installed on the vehicle body. I do. There are also unmanned transport vehicles that travel independently on track.

[0003] The automatic guided vehicle has a built-in battery, and uses this as an energy source to drive a motor to rotate wheels.

FIG. 6 (a) shows a wooden or synthetic resin pallet 2 as an example of an object to be carried by an unmanned carrier.
1 is shown. The height h of the pallet 21 is 100 m
m or less. FIG. 6B shows a container car 22 having a large aspect ratio (L / W) as an example of an object to be carried by an unmanned carrier. L / W of this container truck 22
The ratio is 2 to 4 or more, and the height h from the floor to the bottom of the container vehicle
Is 100 to 350 mm.

[0005] As a truck for transporting an object to be transported shown in Fig. 6, there is a forklift operated by a person or an unmanned transport truck of the forklift type. Since these objects are picked up by forks (claws), the self-weight of the transport vehicle is determined by the relationship between the weight of the transport object and the moment of the transport vehicle's own weight. It is about twice as heavy as the weight of goods.

[0006]

Conventionally, when the pallet 21 or the container truck 22 is lifted by the fork (claw) of the unmanned transport vehicle, the self-weight of the unmanned transport vehicle is conventionally transferred to prevent the unmanned transport vehicle from overturning. It must be about twice as heavy as the thing. For this reason, the total weight of the unmanned transport vehicle and the object to be transported becomes considerably heavy, and when the unmanned transport vehicle is used in a factory or indoors (including higher floors of two or more floors), the load capacity of the floor surface is increased. Therefore, if the allowable load on the floor cannot be increased, there is a problem that it cannot be used.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to reduce the weight of the vehicle body itself and to be used even when the load capacity of the floor cannot be increased. Is proposed.

[0008]

According to the structure of the present invention, which solves the above-mentioned problems, the base is supported by an elevating guide post that slides on the bogie main body, and the base is supported on the bogie main body in accordance with the sliding of the elevating guide post. An unmanned transport vehicle equipped with a fork that can move up and down in a substantially horizontal direction and protrudes and descends along the lift guide post in a state protruding from the carriage body, wherein a lower end portion of the lift guide post is rotatable at a base end. A first frame member attached to the fork and having a distal end portion in contact with the lower surface of the fork; and a base end portion rotatably attached to the base of the fork and a central portion rotatably attached to a central portion of the first frame material. And a second frame member pivotally attached and having a distal end portion in contact with the floor surface, and a bogie overturn prevention frame.

[0009] The structure of the present invention for solving the above-mentioned problems is as follows.
The upper fork support plate supports the tip of the fork when the fork is stored in the bogie body with the fork raised, and the fork tip when the fork is stored in the bogie body with the fork lowered. And a lower fork support plate for supporting.

[0010]

According to the present invention, when the fork is sunk under the object to be conveyed with the X-type bogie falling prevention frame built in, and then the fork is raised by a hydraulic cylinder or the like, X
The overturning prevention frame of the mold also extends at the same time, and the weight of the object to be conveyed is held by the fork lifting mechanism such as a cylinder and the overturning prevention frame of the X-type, thereby preventing the overturning of the carriage body.

When the loaded fork (raised fork) is stored in the bogie main body, the tip of the fork is supported by the upper fork support plate, and the weight of the object to be conveyed is similarly increased by a fork lifting mechanism such as a cylinder. And the fork support plate. These also have the effect of preventing the tip of the fork from being largely bent by the weight of the object to be conveyed. When an unloaded fork (a lowered fork) is stored in the vehicle body, the fork tip is supported by the lower fork support plate.

[0012]

Next, an embodiment of the present invention will be described with reference to FIGS. First, referring to FIG. 1, the bogie main body 1 of the automatic guided vehicle has traveling wheels 2 and travels while detecting a traveling tape 3 laid on the floor with a traveling locus tracking sensor 4. The traveling wheels 2 are oriented at right angles to the traveling direction (A direction) by a steering motor (not shown), and can also travel in a transverse direction (B direction traveling).

The unmanned transport vehicle is provided with a fork 5 which can be protruded and retracted from the vehicle body 1, and can be protruded and retracted from the vehicle body 1 by an unshown motor. That is, the root of the fork 5 is supported by the elevating guide post 9, and the fork 5 slides on the bogie main body 1 so that the fork 5 comes and goes, and the fork 5 moves up and down along the elevating guide post 9. .

Inside the fork 5 (the lower surface side of the fork), an X-shaped bogie overturn prevention frame 6 which can be extended and retracted according to the rise and fall of the fork is built in, and the fork 5 is raised by a hydraulic cylinder 7 for raising the fork. Then, as indicated by the broken line in FIG. 1, the X-type bogie overturn prevention frame 6 extends in accordance with the rise of the fork 5. In this state, if there is an object to be conveyed on the fork 5 (not shown), the bogie overturn prevention frame 6 also carries the own weight of the object to be conveyed, and the bogie main body 1 falls even if the self-weight of the bogie main body 1 is light. You don't have to.

The specific structure and movement of the X-type bogie overturn prevention frame 6 will be described with reference to FIG. Trolley fall prevention frame 6
Then, the base end of the frame member 6a is rotatably attached to the lower end of the elevating guide post 9 by the pin 8a, and the base end of the frame member 6b is rotatably attached to the root of the fork 5 by the pin 8b. The members 6a and 6b are rotatably connected at the center by a pin 8c. The tip of the frame member 6a has a roller 11 and a fork 5
The inside (lower surface) can be guided and the tip of the frame member 6b is provided with a roller 10 to be able to touch and move on the floor.

In such a state, the bogie overturn prevention frame 6
Is built in the fork 5, but when the fork 5 is raised by the fork lifting hydraulic cylinder 7 via the sprocket 12 and the chain 13, the roller 1 of the frame material 6a
1 moves in a trajectory like an arc as shown in the figure,
The cart fall prevention frame 6 extends. In this state, if there is an object to be transported on the fork 5 (not shown), the bogie overturn prevention frame 6 bears the weight of the roller 10 and can prevent the bogie from overturning. Also, when the fork 5 is lowered, the X-type bogie overturn prevention frame 6 is built in the fork 5 by the reverse movement.

Next, the movement and operation when the fork 5 is moved into and out of the bogie main body 1 will be described with reference to FIGS. 1, 3, 4 and 5. FIG.
Here, the movement when the fork 5 is pulled into the bogie main body 1 will be described.

FIG. 3 shows a fork 5 for ease of explanation.
FIG. 4 is a front view when the fork 5 is retracted into the bogie body 1 with the fork 5 lowered, and FIG. 5 is a fork with the fork 5 raised. FIG. 5 is a front view when the carriage 5 is pulled into the carriage main body 1.

First, the situation when the fork 5 is retracted into the bogie main body 1 with the fork 5 raised is described. The fork 5 is a fork retraction motor (not shown) and is pulled into the bogie main body 1 together with the elevating guide post 9.
A roller 14 provided below the elevating guide post 9 rotates on the guide rail 15 and a roller 10 provided on the tip of the bogie fall prevention frame 6 rotates on the floor. At this time, the weight of the conveyed object loaded on the fork 5 is covered by the roller 14 for emergence and the roller 10.

When the fork 5 approaches the retracting end of the bogie main body 1, the guide rail 15 has an inclination,
4 moves up this slope. At the same time, a fork support roller 16 is provided at the tip of the fork, and an upper fork support plate 17 is provided on the bogie main body 1 and has an inclination like the guide rail 15. The fork support plate 17, the inclination of the guide rail 15 and the roller 14 for emergence, and the fork support roller 16 are at relative positions, and the roller 14 for emergence and the support roller 16 simultaneously rotate up the inclined portion of the members 17, 15. The fork 5 is retracted. As a result, the roller 10 which has received the weight of the conveyed object described above leaves the floor, and the weight support of the conveyed object shifts from the roller 10 to the fork supporting roller 16. The projecting roller 14 and the fork supporting roller 16 are combined with the guide rail 15 and the fork supporting plate 1.
After moving over the inclined part 7 and moving to the horizontal part, the fork 5
Is completed, and the automatic guided vehicle can be transported to a predetermined location by driving the wheels 2.

Next, with the fork 5 lowered, the bogie body 1
The situation when the fork is pulled into the fork will be described. At this time, there is no conveyed material on the fork 5.

A retracting roller 14 provided below the elevating guide post 9 rotates on a guide rail 15, and a roller 10 provided at the tip of a bogie fall prevention frame 6 built in the fork 5 rotates on the floor. Wagon body 1
Drawn into. The inclination of the guide rail 15 near the end of the retraction and the movement of the roller 14 are the same as described above, except that the lower fork support plate 18 provided on the bogie main body 1 is provided slightly behind the upper fork support plate 17 and is inclined. Is also bigger. In other words, when the fork support rollers 16 start rotating and rising on the steeply inclined portion of the lower fork support plate 18 while the appearing and retracting roller 14 is rotating and ascending on the inclined portion of the guide rail 15, when both of them move over the inclination and move to the horizontal portion. The retraction of the fork is completed.

The mounting position of the lower fork support plate 18 is provided slightly behind and the inclination is steep. The reason for the operation for pushing out the fork is that the retracting roller 14 is positioned on the inclined portion of the guide rail 15. With fork support roller 16
Is separated from the lower fork support plate 18, the rollers 10 of the bogie fall prevention frame 6 built in the fork land on the fork 5, and the fork 5 assumes a slightly forward inclined posture, so that the loading operation of the conveyed goods becomes smooth.

Also, by providing a projection at the inclined end portion of the guide rail 15, the retracting roller 14 pulled in over the guide rail 15 cannot freely climb over the projection during unmanned transport of the carriage, so that the conveyed article can be stably transferred. Can be transported.

[0025]

According to the present invention, as described above in detail with the embodiments, the bogie main body is overturned because the bogie overturn prevention frame for supporting the fork from below is provided when the fork projects. Can be prevented, safe work can be performed, and the weight of the automatic guided vehicle can be reduced.

Further, when the fork is stored in the bogie main body, the tip of the fork is supported by the fork support plate, so that the fork does not bend significantly.

In a machine using a battery as a power source, durability of the battery capacity becomes a problem. In other words, if the battery capacity is reduced and the power becomes insufficient while the machine is in use and the machine stops during operation, the work up to that point is stopped and the work plan is hindered. Therefore, there is a problem how to save the used battery capacity.

The same can be said for an automatic conveyance unmanned conveyance truck using a battery as a power source. The power supply of the automatic conveyance automatic guided vehicle is turned on by a switch installed on the vehicle. The operator turns on the switch together with the inspection of the automatic guided vehicle before starting the on-site work.

If the power is turned off after the transfer operation in order to save battery capacity, the operator must go to the unmanned transfer truck and turn on the power every time the device is used to restore the communication between the computer and the truck. In order to avoid such inconvenience, the power is kept ON even when there is no automatic transfer operation. Further, even when the apparatus is used in automatic conveyance, if the apparatus is on standby to receive a conveyance command, the power is kept ON for the same reason. If the power is kept on, the power consumption of the battery is large.

To solve these problems, the unmanned transport vehicle itself determines whether or not there is a transport command. If there is no transport command, the power is automatically turned off. A function to turn on is required.

Therefore, in order to save power, an energy saving control method for an unmanned transport vehicle has been developed in which the power is turned off when it is not needed and the power is turned on when it is needed for transportation. The specific method will be described next with reference to FIG. 9 showing a control system of the automatic guided vehicle.

The automatic power-off method of the automatic guided vehicle 100 is performed as follows. That is, it is determined whether or not the power is turned off after the completion of one transfer operation by receiving the next command. That is, after the transfer operation is completed, the timer in the sequence in the control device 101 is operated for the set interval x seconds. If the transport command 103 is not transmitted to the wireless modem 102 during the timer operation, the switch 104 is turned off by a command from the control device 101 and the battery 105 is turned off.
Is automatically shut off. The value of the set interval x can be set freely.

In this case, it is turned off in the automatic guided vehicle 100.
The power supply is a communication function unit for receiving a transfer command in the control device 101 and an electric system 106 other than a memory unit that stores the current position of the cart.

On the other hand, the automatic guided vehicle 100 turns off the power.
The determination to start the transfer from the transfer command input standby state is also made based on whether the transfer command is transmitted to the wireless modem 102. OFF when wireless modem 102 receives a transport command
The switch 104 which has been turned ON is turned on, and the transfer operation is started.

Referring now to FIG. 7, the procedure for automatically shutting down after starting the system will be described. When the system is started, the power of the automatic guided vehicle is turned on (step 1), and the power of the computer is also turned on (step 2). As a result, communication between the cart and the computer is restored (step 3), and subsequently, the timer of the sequence is activated (step 4). When the transport command is not transmitted to the wireless modem during the timer operation and x seconds have elapsed, the cart is automatically turned off (step 5). Then, it enters a transfer command input standby state (step 6).

Next, referring to FIG. 8, the procedure of automatic shutoff during online automatic operation will be described. When a transfer command is transmitted to the automatic guided vehicle (step 11), the unmanned guided vehicle receives the transport command (step 12), and the power of the vehicle is turned on (step 13). Thus, the transfer operation starts (step 14). When the transfer operation is completed (step 15), the timer of the sequence is activated (step 16). When the transport command is not transmitted to the wireless modem during the timer operation and x seconds have elapsed, the cart is automatically turned off (step 17). Then, it enters a transfer command input waiting state (step 18).

The following effects (1) and (2) can be obtained by using the energy saving control method for an unmanned transport vehicle described above. (1) The operator starts the automatic guided vehicle up to the truck, but it takes time and effort to start each time the work is completed. By automatically turning off the power, the power is automatically turned off and automatically turned on at the start of work,
If the operator turns on the power at the time of the inspection of the bogie at the start of the on-site work, the operator can efficiently use the power without any trouble. (2) Since the power is automatically cut off during the transfer operation even when waiting for a command, the power is substantially used only during the transfer operation, so that the battery can be used without waste.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an automatic guided vehicle according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing details of a fork unit.

FIG. 3 is a configuration diagram showing a bogie main body in a state where other parts are omitted.

FIG. 4 is a front view showing a bogie main body and a fork.

FIG. 5 is a front view showing a bogie main body and a fork.

FIG. 6 is a perspective view showing an object to be conveyed.

FIG. 7 is a flowchart showing a procedure of automatic power-off after the system is started.

FIG. 8 is a flowchart showing a procedure of automatic power-off during online automatic operation.

FIG. 9 is a block diagram showing a control system of the automatic guided vehicle.

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 1 bogie main body 2 running wheel 3 running tape 4 running locus tracking sensor 5 fork 6 bogie overturn prevention frame 6a, 6b frame material 7 fork lifting hydraulic cylinder 8a, 8b, 8c pin 9 elevating guide post 10, 11 roller 12 sprocket 13 Chain 14 Roller for emergence 15 Guide rail 16 Fork support roller 17 Upper fork support plate 18 Lower fork support plate

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Nagisa Minami 4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima-shi, Hiroshima Mitsubishi Heavy Industries, Ltd. Hiroshima Research Laboratory (72) Inventor Noboru Oyamada Kannon-Shimmachi 4 in Nishi-ku, Hiroshima-shi, Hiroshima No. 6-22, Mitsubishi Heavy Industries, Ltd., Hiroshima Works (72) Inventor Masaru Yasuda 4-62, Kannon Shinmachi, Nishi-ku, Hiroshima, Hiroshima Prefecture, Mitsubishi Heavy Industries, Ltd., Hiroshima Works (72) Inventor Hajime Nomura, Minato-ku, Tokyo 1-3-2 Shibaura Shimizu Corporation (72) Inventor Jun Nishimura 1-3-2 Shibaura Minato-ku Tokyo, Japan Inside (72) Inventor Tsutomu Kato One Shibaura Minato-ku Tokyo 2-3-2 Shimizu Corporation (72) Inventor Tadashi Okano 1-3-2 Shibaura Minato-ku, Tokyo Inside Shimizu Corporation (56) References JP Sho 5 9-182198 (JP, A) JP-A-62-116499 (JP, A) JP-A-63-265761 (JP, A) JP-A 4-70568 (JP, U) JP-A 60-195266 (JP, A) U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B61B 13/00 B61D 47/00

Claims (2)

(57) [Claims] An elevating guide post that slides on a bogie main body has a root supported, and is capable of protruding and retracting in a substantially horizontal direction with respect to the bogie main body in accordance with the sliding of the elevating guide post, and protruding from the bogie main body. An unmanned carrier provided with a fork that moves up and down along the elevating guide post in a state, wherein a base end is rotatably attached to a lower end of the elevating guide post and a leading end contacts a lower surface of the fork.
And a second frame whose base end is rotatably attached to the base of the fork and whose center is rotatably connected to the center of the first frame so that its tip is in contact with the floor. An unmanned transport cart, comprising a cart and a frame for preventing the cart from falling. 2. An upper fork support plate for supporting a tip portion of a fork when the fork is stored in the bogie main body with the fork raised, and the fork with the fork lowered when the fork is lowered. And a lower fork support plate for supporting the tip of the fork when stored in the unmanned carrier.