JPH0524963Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a safety bumper control device for an automatic guided vehicle.

(Prior Art) Conventionally, automatic guided vehicles have been used to transport assembled parts, materials, products, etc. in manufacturing plants, processing plants, etc. The automated guided vehicle receives commands from a ground control room located in a corner of the factory, and is guided by the vehicle's detector while receiving magnetic fields from guide wires embedded in the passageway within the factory, from the desired location. It transports goods from place to place.

By the way, some automatic guided vehicles are equipped with safety bumpers at the front and rear, and if a person or obstacle comes into contact with the safety bumpers during automatic driving, the power to the control system is cut off or the brake release signal is cut off. Some vehicles are designed to make a sudden stop to ensure safety. In this type of automated guided vehicle, in order to continue operating after hitting an obstacle and stopping during automatic driving, the driving mode must be switched from automatic to manual, avoid the obstacle, and then switch back to automatic driving mode. A method of switching is used. For this reason, conventional circuits have been designed so that the safety bumper does not work in the manual driving mode, or the circuit has been designed such that the safety bumper control circuit is canceled by a switch. For this reason, if the former circuit configuration is adopted, the automated guided vehicle will not stop even if a person or obstacle comes into contact with the safety bumper due to an erroneous operation while driving in manual driving mode, and the latter circuit configuration is adopted. In this case, if the safety bumper control circuit is not restored due to forgetting to operate the switch after it has been released, the same problem as the former occurs.

(Purpose and structure of the invention) The present invention has been made in view of the above points, and is designed to ensure that the automatic guided vehicle is safe even if the automatic guided vehicle hits an obstacle, avoids it, and then comes into contact with a person or obstacle again. In order to achieve this goal, automatic and manual driving are used in automatic guided vehicles that are designed to stop suddenly by cutting off the power to the control system. a changeover switch for performing the switching; and a contact drive stop means for stopping the drive of the automatic guided vehicle by cutting off the control system power of the automatic guided vehicle when an obstacle comes into contact with the safety bumper while driving; Manual travel means upon contact that enables manual travel of the automatic guided vehicle by supplying control system power to the automatic guided vehicle if the safety bumper is in contact with an obstacle when the changeover switch is switched to manual travel. ,
When the automatic guided vehicle is manually driven by the contact manual travel means and the contact between the safety bumper and the obstacle is removed, even if the changeover switch is in a state where manual travel is selected, the contact drive stop means A means for stopping the drive upon re-contact is provided.

(Example) The present invention will be explained below based on the drawings.

FIG. 1 shows an embodiment of a safety bumper control device according to the present invention.

In the figure, _SW1 is a manual drive switch that is turned on when the automatic guided vehicle is driven manually (manual drive mode), and _SW2 is an automatic drive switch that is turned on when the automatic guided vehicle is driven automatically (automatic drive mode). One contact of the manual drive switch _SW1 is a
Between this terminal and earth (GND), a normally closed contact 2b of a safety bumper signal relay 2 (described later) and a delay relay 8 for temporary cancellation of the safety bumper are connected in series.

On the other hand, a contact 5c of a control power supply relay 5 and an automatic/manual switching relay 7, which will be described later, are connected in series between one contact c of the automatic travel switch SW ² and the ground (GND).

SW ₁ and SW ₂ are linked, and SW ₁
When SW ₂ is turned ON, SW 2 is turned OFF, and when SW ₂ is turned ON, SW ₁ is turned OFF. Furthermore, when one of them is turned OFF from the ON state, the other is not turned ON, and both SW ₁ and SW ₂ are turned OFF. this
SW ₁ and SW ₂ act as a changeover switch to switch between automatic driving and manual driving.

The other contact b of manual travel switch SW ₁ and the other contact d of automatic travel switch SW ₂ are commonly connected at point A, and between this point A and ground (GND), delay relay 1 and , the series circuit between the four normally closed safety bumper switches SW ₃ (two each installed at the front and rear of the transport vehicle) and the safety bumper signal relay 2, and the control microcomputer installed in the transport vehicle are normal. A series circuit consisting of a transistor 3 that is turned ON when an error occurs and OFF when an error occurs, and a microcomputer error relay 4 that is energized when an error occurs are connected in parallel.

Furthermore, between the common point A of manual travel switch SW ₁ and automatic travel switch SW ₂ and the ground (GND), there are switches installed at the front and rear corners of the transport vehicle that can be turned off manually in the event of an abnormal situation while traveling. 4 emergency stop switches SW ₄ and microcomputer error relay 4
the contact 4a of the safety bumper signal relay 2, the control power relay 5 and its contact 5a
At the same time, the contact 8a of the safety bumper temporary cancel delay relay 8 is connected in parallel with the contact 2a, and the series circuit between the power return switch SW ₅ and the contact 1a of the delay relay 1 is connected in parallel with the contact 5a. A circuit is connected, and a lamp 6 for displaying the operating state is connected in parallel with the control power supply relay 5. In this embodiment, the safety bumper temporary canceling delay relay 8, the contact 2b of the safety bumper signal relay 2 connected in series with the delay relay 8, and the contact 8a of the delay relay 8 are used as temporary canceling means (shown surrounded by a dashed line). ).

In addition, the common point A is the contact 5 of the control power supply relay 5.
It is connected to a control system power supply (not shown) via b.

Next, the operation of the safety bumper control device having the above circuit configuration will be explained.

During normal driving, automatic driving switch SW ₂
When turned ON, the power supply voltage Vc is supplied to the common point A. As a result, the delay relay 1 is energized and its contacts 1a are closed, and the safety bumper signal relay 2 is also energized and its contacts are energized as long as the conveyance vehicle does not come into contact with an obstacle and neither of the safety bumper switches SW ₃ is turned OFF. 2a is closed and contact 2b is open.

On the other hand, if the control microcomputer is operating normally at this time, the transistor 3 is on, so the microcomputer failure relay 4 is also energized, and its contact 4a is closed.

The operator then turned on the power return switch _SW5 .
When turned ON, the control power relay 5 is energized, its contact 5b is closed, and power is supplied to the control system, and the contact 5c is also closed, and the automatic/manual switching relay 7 is energized. In this way, normal automatic driving is performed.

Now, if the conveyance vehicle comes into contact with an obstacle and its safety bumper is pressed, one of the four bumper switches SW ₃ will be turned OFF. the result,
Since the safety bumper signal relay 2 is deenergized and its contact 2a is opened, the control power supply relay 5 is also deenergized and the traveling of the transport vehicle is stopped. In other words, this
Turn off SW ₃ , de-energize relay 2, open contact 2a,
De-energizing of relay 5, opening of contact 5a and contact 5b
The opening acts as a drive stop means upon contact. At this time, the operation indicator lamp 6 turns off and the contact 2b
closes. The operator then turns on the automatic travel switch.
When SW ₂ is turned OFF and manual travel switch SW ₁ is turned ON, the delay relay 8 is energized after a certain time delay and its contact 8a is closed. This is a manual travel switch
This is to prevent runaway behavior due to incorrect operation of SW ₁ .
In this state, the operator presses the power return switch _SW5 .
When turned ON, contacts 4a and 8a, power switch
SW ₅ , the power supply voltage Vc is supplied to the control power supply relay 5 through the contact 1a, so the operation indicator lamp 6 also lights up, the previous travel stop function is canceled, and the vehicle becomes ready for manual travel. As explained above,
Turn on SW ₁ , energize relay 8, close contact 8a,
Activation of relay 5, closing of contact 5a and contact 5b
The closure acts as a manual traveling means upon contact. The operator uses a control box (not shown) to manually operate the transport vehicle to move the transport vehicle forward and backward to avoid obstacles.

When the conveyance vehicle moves away from the obstacle, all of the safety bumper switches SW ₃ return to the ON state, so the safety bumper signal relay 2 is energized. As a result, contact 2a is closed, normally closed contact 2b is opened, and since delay relay 8 is deenergized, its contact 8a is also opened. At this time, the power supply circuit to the control power relay 5 is switched from the previous one via the contact 8a to the one via the contact 2a, and the running stop function is restored again even during manual running. As explained above, SW ₃ 's
ON, relay 2 energized, contact 2a closed, contact 2
Opening of contact b, deenergization of relay 8, opening of contact 8a, energization of relay 5, closing of contact 5a, and closing of contact 5b serve as drive stopping means upon re-contact.

Thereafter, by turning off the manual running switch SW ₁ and turning on the automatic running switch SW ₂ , the vehicle returns to the automatic running state described above.

By the way, if a person or obstacle comes into contact with the bumper again during automatic driving immediately after returning to the state where automatic driving is possible, the control power relay 5 is deenergized and the control system power supply is turned off in the same way as described above. Running is stopped because the supply is cut off.

FIG. 2 shows another embodiment of the safety bumper control device according to the present invention, in which the same components as in FIG. 1 have the same reference numerals.

The difference between this embodiment and the embodiment shown in FIG. 1 is that instead of using a series circuit between the delay relay 8 and the normally closed contact 2b of the safety bumper signal relay 2, the circuit is connected between the common point A and the ground (GND). In addition, the safety bumper temporary cancel delay relay 8 and the contact 9b of the safety bumper temporary cancel set relay 9 (described later) are connected in series, and the safety bumper temporary cancel relay 8 is connected in series between the contact a of the manual travel switch SW ₁ and the ground (GND). Bumper temporary cancel set relay 9 and its contacts 9
a and the normally closed contact 2b of the safety bumper signal relay 2
A series circuit is connected to the contact 9a, and a temporary cancel switch SW ₆ is connected in parallel with the contact 9a, which is ON only while the switch is pressed. In this embodiment, the safety bumper temporary cancel delay relay 8, the safety bumper temporary cancel cut relay 9, its contacts 9a and 9b, the temporary cancel switch SW ₆ , and the contact 2b of the safety bumper signal relay 2 are used. It constitutes a canceling means (shown surrounded by a dashed line).

With this circuit configuration, when the conveyance vehicle comes into contact with an obstacle and the bumper is pushed (in this case, the normally closed contact 2b of the safety bumper signal relay 2 is closed, as in the above-mentioned embodiment), the operator When the temporary cancel switch SW ₆ is pressed momentarily, the safety bumper temporary cancel set relay 9 is energized, and its contact 9a closes, so it is self-holding, and its contact 9b also closes, so the safety bumper temporary cancel delay relay 8 is activated. The contact 8a is energized to close.

Subsequent operations by the operator and circuit operations are the same as in the previous embodiment, so their explanation will be omitted. However, when the obstacle is avoided by manual driving, the safety bumper signal relay 2 is energized again, and as a result 2b is opened, relay 9 is deenergized, and delay relay 8 is further deenergized. As a result, the travel stop function up to that point is canceled.

Note that voice input means may be used instead of the temporary cancel switch SW ₆ provided in this embodiment.

In either embodiment, when an obstacle comes into contact with the safety bumper of the automatic guided vehicle, the travel stop function of the safety bumper control device is canceled after a certain time delay, and when the obstacle is subsequently avoided, the travel stop function is canceled. is automatically reset, so even if an obstacle or person comes into contact with the transport vehicle again and pushes the safety bumper, the safety bumper control device will operate reliably and stop the transport, ensuring safety. can do.

(Effects of the invention) As explained above, according to the invention, there is no need to operate a switch to restore the travel stop function of the safety bumper control device as in the conventional case.
Therefore, since there is no possibility of forgetting to return to the original position, if the bumper comes into contact with the obstacle again after the obstacle has been avoided, the safety bumper control device will surely operate and the conveyance vehicle will stop, which is preferable in terms of safety.

[Brief explanation of the drawing]

FIG. 1 shows one embodiment of the safety bumper control device according to the present invention, and FIG. 2 shows another embodiment of the safety bumper control circuit according to the present invention. 1... Delay relay, 2... Safety bumper signal relay, 4... Microcomputer error relay, 5... Control power supply relay, 7... Automatic/manual switching relay, 8
...Delay relay for safety bumper temporary cancellation,
1a, 2a, 2b, 5a, 5b, 5c, 8a...
contact.

Claims (1)

[Scope of utility model registration request] In an automated guided vehicle that is stopped by cutting off power to a control system, a changeover switch for switching between automatic driving and manual driving;
A contact drive stop means for stopping the drive of the automatic guided vehicle by cutting off the control system power of the automatic guided vehicle when an obstacle comes into contact with the safety bumper while traveling, and when the changeover switch is switched to manual traveling. a manual travel means upon contact that enables the automatic guided vehicle to travel manually by supplying power to the control system of the automatic guided vehicle if the safety bumper is in contact with an obstacle; Re-contact drive stop means for operating the contact drive stop means even when the changeover switch selects manual travel when the safety bumper is driven manually by the travel means and the contact with the obstacle is removed. A safety bumper control device for an unmanned guided vehicle, characterized by comprising: