JPH045602B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides two
The present invention relates to a device for preventing table moving devices, such as moving cranes for loading and unloading in an automated warehouse, from interfering (colliding) with each other at the end of the moving path.

(Prior art and its problems) In an automated warehouse, when a storage shelf is divided into two with respect to the crane traveling direction and two traveling cranes for loading and unloading are used to divide loading and unloading work for each shelf area, These two cranes will travel in one crane passage along the storage shelf, and when the crane enters and exits the storage section adjacent to the divided position of the storage shelf, the crane A portion will protrude into the other party's crane movement path. In other words, the respective movement path ends of the two cranes overlap each other. In such a situation, for example, if one crane is working in a storage section near the dividing position of the storage shelf and the other crane moves towards a storage section near the dividing position of the storage shelf, Both cranes end up colliding with each other.

As a method to avoid collisions between cranes in such automated warehouses, for example,
- As disclosed in Publication No. 4451, for each of two moving devices whose moving path ends overlap each other, it is detected that each moving device has entered an interference zone set at each moving path end of each moving device. A detector is installed,
There is a known method of controlling such that when the detector of one mobile device is in the interference zone entry detection state, the other mobile device cannot enter the interference zone.

That is, in the method, when the other moving device enters the interference zone and the detector of the moving device enters the interference zone entry detection state, the detector of one moving device also enters the interference zone entry detection state. If,
Since the traveling of the other moving device is automatically stopped, in order to implement the method, means for transmitting to the other moving device that the detector of one moving device is in the interference zone entry detection state is required. is necessary.

As the above-mentioned publication does not specifically disclose this point, conventionally, no consideration has been given to means for transmitting the detection state of each detector between mobile devices to the other mobile device. It was thought that it would be sufficient to simply transmit signals using normal signal transmission means such as wiring. However, if it is attempted to communicate the detection status of the detectors between mobile devices using ordinary signal transmission means such as wiring, the cost will be extremely high.

(Means for Solving the Problems) The present invention proposes an interference prevention device that can solve these conventional problems. Each of the devices includes a detector for detecting entry into an interference zone set at each end of the moving path of each moving device; a light projector that enters a light projecting state only when this detector is not in an interference zone detection state; and a light receiver that receives the light beam from the light projector of the other moving device, and the moving device enters the interference zone, the detector of the moving device is in an interference zone detection state, and the light receiver is in a non-light receiving state. The present invention is characterized in that a control means is provided to automatically stop the moving device at certain times.

(Operations and Effects of the Invention) According to the device of the present invention, when one of the moving devices A is within the interference zone, the detector of the moving device A enters the interference zone detection state and the projector does not emit light. state (OFF state). When the other moving device B enters the interference zone in such a state, the detector of this moving device B enters the interference zone detection state, and the light receiver is not receiving the light beam from the projector of moving device A, so the control described above is performed. By means of this means, mobile device B is automatically stopped when it enters the interference zone and before it collides with mobile device A. Even if mobile device A enters the interference zone while mobile device B has entered the interference zone first, the mobile device A is automatically stopped by the same effect.

Therefore, even if both moving devices should enter the interference zone due to a programming error or a failure in the control system, it is possible to prevent both moving devices from colliding with each other.

Moreover, according to the present invention, since the emitter and the light receiver are used as a means for transmitting the detection state of the detector between the mobile devices, it is necessary to install signal transmission wiring between the two mobile devices, It is not only possible to implement it at a very low cost compared to the usual method such as using a transmission rail and a current collector, but also to automatically stop the other moving device when the projector is turned off. As this is one of the conditions, even if the projector is turned off even though the projector is not in the interference zone due to a malfunction in the projector system, there is a risk that both moving devices will collide with each other within the interference zone. However, safety can also be improved.

(Example) An example of the present invention will be described below based on the attached illustrative drawings.

In FIG. 1, reference numeral 1 denotes a storage shelf, which is erected on both left and right sides of a crane passage 2, and is divided into two shelf areas 1A and 1B with respect to the crane traveling direction. Numerals 3 and 4 are traveling cranes for loading and unloading that travel within the crane passage 2 along the storage shelf 1. Crane 3 is responsible for loading and unloading work for storage section 5 in shelf area 1A, and crane 4 is responsible for loading and unloading work for storage section 5 in shelf area 1A. They share the work of loading and unloading the storage unit 6. 7,8
9 and 10 are delivery conveyors.

In such an automated warehouse, the storage shelf 1
When the crane 3 or the crane 4 is stopped in response to the storage section 5a or the storage section 6a adjacent to the boundary position (divided position) P between the shelf areas 1A and 1B, the crane 3 or the crane 4 A part of the crane protrudes into the crane path adjacent to the shelf area 1B or 1A, which is the work target of the other crane 4 or crane 3. In other words, the moving path ends of both cranes 3 and 4 overlap each other. Therefore, when the crane 3 or the crane 4 is stopped in response to the storage section 5a or the storage section 6a adjacent to the boundary position (divided position) P between both shelf areas 1A and 1B, the other crane 4 or crane It is possible to set interference zones 1C and 1D where there is a risk of collision with the crane 3 or 4 if the crane 3 enters.

2 and 3, reference numerals 11 and 12 are detection plates fixed to the side of the crane movement path (on the floor, etc.) over the entire length of each of the interference zones 1C and 1D, and each crane 3 and 4 are the detection target plates 1
Detectors 13 and 14 are provided to detect entry into the interference zones 1C and 1D via the interference zones 1 and 12, respectively. The detectors 13 and 14 include reed switches that magnetically detect the detection plates 11 and 12 made of magnetic plates, and photoelectric switches that optically detect the detection plates 11 and 12 made of light reflecting plates or light shielding plates. A switch or a limit switch that detects contact can be used.

As shown in FIG. 2, each of the cranes 3 and 4 has a light projector 15, 16 that emits light toward the other crane, and a light projector 16, 1 of the other crane.
5, a retroreflective photoelectric switch 2 that detects the light reflecting plates 20, 19 of the other crane;
1, 22, and contact detection means 23 shown in FIG.
24 are provided. This contact detection means 23,
24 is a push rod 25, 2 protruding from each crane 3, 4 toward the other crane.
6. The slide rods 29, 30 move backward against the springs 27, 28 when pushed by the opposing push rods 26, 25, and the slide rods 29, 30 are prevented from moving backward by the slide rods 29, 30 attached to the slide rods 29, 30. Limit switch 3 detected via cams 31 and 32
It consists of 3,34.

FIG. 5 is a circuit diagram showing in principle the control means provided in each crane 3, 4, and is a circuit diagram showing the control means provided in each crane 3, 4.
3 is a relay, R1b and R2b are b contacts of relays R1 and R2, and R3a is an a contact of relay R3. To explain the configuration of the control means using the crane 3 as an example, as shown in FIG. When the light is off, it is in the light emitting state (ON state), and when the crane 3 enters the interference zone 1C and the detector 13 is switched to the ON state, the light is not emitting state (OFF
state). Also, when the crane 3 enters the interference zone 1C and the detector 13 is turned on, the light receiver 17 is connected to the emitter 16 of the other crane 4.
If it is in the OFF state, not receiving any light from
A deceleration and stop command 36 is given to a speed and braking controller 35 provided in the crane 3 . Further, when both cranes 3 and 4 approach within a certain distance and the recursive reflective photoelectric switch 21 detects the light beam reflector 20 of the other crane 4, and when both cranes 3 and 4 approach each other and the contact detection means 23
is activated, that is, when the slide rod 29 is moved backward against the spring 27 by the push rod 26 of the other crane 4 and the limit switch 33 is turned on by the cam 31, the speed and brake controller 35 is An emergency stop command 37 is given.

The crane 4 is also equipped with the same controller as the speed and braking controller 35, and is configured to be controlled in exactly the same way as the crane 3.

Loading/unloading operations for the storage section 5 in the shelf area 1A by the crane 3, and loading/unloading operations for the shelf area 1B by the crane 4
The loading and unloading operations for the storage section 6 are performed in the same manner as in the conventional case. Of course, both cranes 3 and 4 can carry out loading and unloading operations simultaneously in their respective work areas, but for example, when the crane 4 is in the storage area 6 of the shelf area 1B, the storage area in the interference zone 1D is When carrying out loading/unloading work, the detector 14 detects the detected plate 1.
2 is detected and is in the ON state, so the floodlight 16 is
It is switched to OFF state. Therefore, the light receiver 17 of the other crane 3 is in the OFF state. However, when the crane 3 is outside the interference zone 1C, the detector 13 is not detecting the detected plate 11 (it is in the OFF state), so the speed and braking controller 35 of the crane 3 is not decelerating. No stop command 36 is given. That is, crane 3
can carry out loading and unloading operations according to the normal automatic operation program.

If the crane 3 were to enter the interference zone 1C for some reason in the above situation, the detector 13 would detect the detection plate 11 since the light receiver 17 would be in the OFF state as described above. do
When switched to the ON state, a deceleration and stop command 36 is given to the speed and brake controller 35, and the crane 3 automatically decelerates and stops, and the interference zone 1D
Collision with the crane 4 working inside can be avoided.

However, during deceleration and stop control based on this deceleration and stop command 36, when the crane 3 approaches within a certain distance to the crane 4 in the interference zone 1D, the retroreflective photoelectric switch 21
Since the light reflecting plate 20 is detected and turned on, an emergency stop command 37 is given to the speed and brake controller 35, and the crane 3 is immediately brought to an emergency stop. Also, when the crane 3 approaches the crane 4 to a position where the limit switch 33 of the contact detection means 23 is switched to the ON state, an emergency stop command 37 is given to the speed and brake controller 35, and the crane 3 immediately comes to an emergency stop. I am forced to do it. In addition, the contact detection means 2
3 and 24, a forced braking means separate from the speed and braking controller 35 may be operated.

As mentioned above, if the crane 3 enters the interference zone 1C while the crane 4 is within the interference zone 1D, the crane 3 is automatically stopped, but conversely, when the crane 3 is within the interference zone 1C When the crane 4 enters the interference zone 1D, the crane 4 is automatically stopped by the same control as described above.

In this manner, when both cranes 3 and 4 are stopped within the interference zones 1C and 1D, both cranes 3 and 4 can be moved in the backward direction to exit from the interference zones 1C and 1D. Therefore, when the crane 4 exits the interference zone 1D after entering the interference zone 1C and being automatically stopped as described above, the light projector 16 of the crane 4 is turned on, and the light receiver 17 of the crane 3 is turned on.
is switched to the ON state, so that the crane 3 can be moved toward the storage area for loading/unloading work in the interference zone 1C.

In order to further improve safety, auxiliary detectors 13a and 14a that perform the same detection function as the interference zone detectors 13 and 14 are added as shown in FIG. 3, and a floodlight is added as shown in FIG. Auxiliary light emitters 15a, 16a and auxiliary light receivers 17a, 18a that perform the same functions as 15, 16 and light receivers 17, 18
The auxiliary floodlights 15a and 16a are controlled ON and OFF by the auxiliary detectors 13a and 14a.
It is also possible to perform the above control by the operation of either one of the light receivers 15, 16 and the auxiliary light receivers 15a, 16a.

[Brief explanation of drawings]

Figure 1 is a schematic plan view showing the entire automated warehouse, Figure 2
The figure is a schematic side view showing two moving cranes for loading and unloading, and Figure 3 is a perspective view showing interference zone detection means.
FIG. 4 is a plan view showing the contact detection means, and FIG. 5 is a principle circuit diagram of the control means. 1... Storage shelf, 1A, 1B... Divided shelf area, 1C, 1D... Interference zone, 3, 4... Traveling crane for loading and unloading (mobile device), 5, 5a, 6,
6a... Storage section, 11, 12... Detection plate, 1
3, 14... Interference zone detector, 15, 16...
Emitter, 17, 18...Receiver, 19, 20...
Light reflecting plate, 21, 22...Regression reflection type photoelectric switch, 23, 24... Contact detection means, 25, 26
...Push rod, 27,28...Spring, 29,30...Slide rod, 31,32
...Cam, 33, 34...Limit switch, 3
5... Speed and braking controller, 36... Deceleration stop command, 37... Emergency stop command.

Claims (1)

[Claims] 1. A detector for each of two moving devices whose moving path ends overlap each other to detect that the moving device has entered an interference zone set at each moving path end of each moving device, this detector is an interference zone detection A light emitter that enters the light emitting state only when the other mobile device is not in the light emitting state, and a light receiver that receives the light beam from the light emitter of the other moving device are provided, and when the moving device enters the interference zone, the detector of the moving device detects the interference zone. An interference prevention device between two moving devices, comprising a control means for automatically stopping the moving device when the light receiver is in the non-light receiving state.