JPS61170811A - Positioning device of unmanned carrier car - Google Patents

Abstract

PURPOSE:To load/unload baggages precisely to/from a bed by arranging right and left contact detectors independently and generating a stop command from a stop time control means. CONSTITUTION:The right and left contact detectors (e), (f) are independently fitted to the right and left sides of the front end of an unmanned carrier car to be positioned. The rotation of a driving wheel on the detecting side is stopped by a turning movement control means (g) in response to any one of the outputs of the detectors (e), (f). A turning angle is started to be measured from the time of rotation by a turning angle measuring means (h). If a detecting signal is outputted from the other detector before the turning angle reaches an allowable value, a stop command is generated by a stop time control means (i). If the signal is not outputted, the stop command is generated when the turning angle reaches said allowable value. Even if the bed of the carrier car is shifted, normal loading operation is continued when the shift is included within the allowable range. When the shift exceeds the allowable range, the loading operation is inhibited, so that the carrier car can be previously prevented from the falling of baggages.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a positioning device for an automatic guided vehicle that allows loads to be accurately stacked or unloaded even when a loading platform is curved.

(Prior art and its problems) As a conventional positioning device for an automatic guided vehicle, for example, one described in Japanese Patent Publication No. 59-355135 is known.

However, in such conventional devices, the contact detectors installed on the left and right sides of the front end of the transport vehicle were configured to stop the vehicle only when both of them were turned on. If the loading platform is bent, even if one of the contact detectors turns on, the vehicle will continue to move forward until the other contact detector turns on, and there is a risk that the cargo may fall over. Ta.

On the other hand, in order to solve this problem, if the vehicle is configured to stop only when one of the contact detectors is turned on, it is possible to prevent the cargo from collapsing due to forward pressure, but on the other hand, The problem is that it cannot be used for practical use because it cannot be loaded or unloaded at all.

(Objective of the Invention) The object of the present invention is to ensure that even if the loading platform is bent relative to the conveying vehicle, the conveying vehicle will not forcefully push the loading platform, and moreover, it will be possible to accurately load or unload onto the loading platform. An object of the present invention is to provide a positioning device for an automatic guided vehicle that enables the positioning of automatic guided vehicles.

(Structure of the Invention) The first invention of the present application will be described in detail with reference to the claim correspondence diagram in FIG.

The left contact detector a and the right contact detector A are independently provided on the left and right sides of the front end of the carrier, and are supported so that they can be moved backward by the reaction force when they come into contact with an object in front of them.

The straight distance measuring means C includes the left and right contact detectors a and b.
Measurement is started in response to the contact detection output of either one.

When a contact detection output is obtained from the other contact detector before the measured distance reaches the allowable value, the stop timing control means d issues a stop command in response to the contact detection output, and When a contact detection output is not obtained from the detector, a stop command is issued when the permissible value is reached. -Next, the second invention of the present application will be explained in detail with reference to the claim correspondence diagram in FIG.

The left contact detector e and the right contact detector f are independently provided on the left and right sides of the front end of the carrier.

The turning transition control means Q includes the left and right contact detectors e and f.
In response to the contact detection output of either one of the contact detection side drive wheels, the rotation of the contact detection side drive wheel is stopped and a turning operation is started.

The turning angle measuring means starts measurement at the time of transition to the turning operation.

When a contact detection output is obtained from the other contact detector before the measured angle reaches the allowable value, the stop timing control means i issues a stop command in response to the contact detection output, and prevents the other contact detection from occurring. When a contact detection output is not obtained from the detector, a stop command is issued when the permissible value is reached.

(Description of Embodiments) FIG. 3 schematically shows the configuration of an automatic guided vehicle according to a first embodiment of the present invention. As shown in the figure, this automatic guided vehicle 1 is equipped with left and right drive wheels 4 and 5 that are driven independently via motors 2 and 3, and is driven along a guide line buried in the road surface (not shown). It is equipped with an automatic steering mechanism for driving.

Furthermore, independent contact detectors 7 and 8 are attached to the left and right sides of the front end of the vehicle body 6, respectively.

When these contact detectors 7 and 8 come into contact with a loading platform or the like while moving forward, they immediately detect this and issue a predetermined detection output, and then move backward a certain distance l due to the reaction force generated by contact with the object in front. Possibly supported.

Some examples of specific structures of contact detectors are shown in Figures 4 and 5.
As shown in the figure.

The contact detector shown in FIG. 4 has a limit switch 9 attached to the front of the vehicle body 6, a contact detection plate 11 attached to the front of the limit switch 9 via a return spring 10, and a moderate limit switch attached to the back of the contact detection plate 11. The limit switch 9 is pressed through a protective spring 12 of sufficient strength.

That is, when the contact detection plate 11 comes into contact with the forward object as shown in FIG. 4(B) from the state in which no forward object exists as shown in FIG. 4(A), the limit switch 9 is pressed via the protective spring 12 After that, the contact detection plate 11 retreats against the force of the return spring 10, as shown in FIG.
When the protection spring 12 is retracted by a distance l shown in , the protection spring 12 is compressed to the limit position to protect the limit switch 9 from overload.

In the case of the contact detector shown in FIG. 5, a contact detection arm 13 is swingably supported at the front end of the vehicle body 6 via a spring 14, and a limit switch 15 attached to the base of this arm 13 is connected to the arm 13. The pressing operation is performed by a cam 16 that is interlocked with the cam 16.

That is, when the state in which there is no object in front as shown in FIG. 5 (A) changes to the state in which the arm 13 is in contact with the object in front as shown in FIG. Also, the limit switch 15 is connected to the cam 16.
continues to be pressed through. As shown in FIG. 2C, when the arm 13 is retracted by a certain distance, the spring 14 is fully extended to its limit.

Next, FIG. 6 is a block diagram showing the electrical hardware configuration of the device according to the first embodiment of the present invention.

As shown in the figure, this device has a microcomputer 17.
It is mainly composed of the left side mentioned above.

The output from the right contact detector 7.8 is read, and at the same time, the output from the left and right wheel pulse generators 18 and 19, which generate pulse trains corresponding to the rotation speeds of the left and right wheels 4 and 5, is read. By executing the flowchart in FIG. 7, the left wheel motor 2. The right wheel motor 3 is appropriately driven and controlled.

In addition, 22 is various detectors used for cargo handling, travel control, etc., 23 is a load-throwing equipment drive circuit, and 24 is a load-throwing equipment.

Next, with reference to the flowchart in FIG.
The operation of the embodiment device will be systematically explained.

Until reaching the target cargo handling work point, the right side contact detector 8. The operating state of the left contact detector 7I is repeatedly checked (step 100.200).

In this state, if the contact detector 8 on the right side is ON
Assuming that it is (step 1004 fixed), in response to this, measurement of the forward traveling distance is started (step 101).
.

The method for measuring this straight-line traveling distance is to use the left wheel pulse generator 1.
This is done by measuring these pulses and calculating distance data based on signals from either the right wheel pulse generator 8 or the right wheel pulse generator 19.

The straight travel distance determined in this way is the predetermined allowable distance Ii! Ii When the left side contact detector turns on before reaching the grass (step 102 is affirmative), the left and right wheel motors 2 and 3 are immediately braked via the left and right wheel drive circuits 20 and 21, and the unmanned guided vehicle stops. .

Tolerance for this! If the left side contact detector 7 does not turn on even when the left side contact detector 7 is turned on (Yes in Step 103), it is determined that the loading platform or the carrier is significantly bent, and the vehicle stops in that state (Step 400). .

On the other hand, if the left side contact detector 7 is turned on while reaching the target cargo handling point (step 200)
, the same processing as in the case on the right side is performed (step 201
~203,300,400>.

Therefore, as shown in FIG. 8 (A>), the loading platform 2 is
5 is slightly bent (the degree of bending is within the allowable range), even if one of the contact detectors is turned on, the vehicle will continue to move forward and will be in a state where it is approximately directly facing the loading platform 25. By making a positioning stop and issuing a positioning completion command to the loading device drive circuit 23, subsequent cargo handling operations can be carried out without any trouble.

On the other hand, as shown in FIG. 8(B), if the loading platform 25 is significantly curved with respect to the vehicle, the vehicle will move a distance l
The load-throwing equipment drive circuit 23 stops at a position advanced by
No instructions were given to the ship, and cargo handling operations were prohibited from then on. For this reason, when the loading platform 25 is bent, the transport vehicle is forced to move onto the loading platform 25.
5 or the loading operation can be carried out without any change, thereby preventing the possibility of the cargo collapsing.

Next, FIG. 9 is a flowchart showing the software configuration of the second embodiment of the present invention, and since the hardware configuration of the second embodiment is the same as that of FIG. 6, a description thereof will be omitted.

The feature of this second embodiment is that, as in the case of the "first" embodiment, when either one of the contact detectors turns on, the vehicle does not stop immediately, but turns until it is directly facing the loading platform. The purpose is to prohibit further loading and unloading operations only when the vehicle turns at an angle and does not directly face the loading platform.

That is, as in the first embodiment, the microcomputer repeatedly checks the operating states of the left and right contact detectors 7.8 until the target cargo handling point is reached (steps 500 and 600).

In this state, if we assume that the right contact detector 8 is turned on, the right wheel will be braked immediately (
Step 501>, the vehicle starts turning to the right, and at the same time, the turning angle θ is indirectly measured based on the rotation speed of the left wheel (Step 502).

If the left side contact detector 7 is turned on as shown in FIG. 10(A) until this turning angle θ reaches the allowable turning angle θ, the left wheel is Braking is also applied, and the positioning work is completed (step 700).

On the other hand, if the left side contact detector 7 reaches the allowable turning angle without operating while the vehicle is turning as shown in FIG. The left wheel is also braked, prohibiting further cargo handling operations, and similarly to the first embodiment, it is possible to prevent the cargo from collapsing due to incorrect loading.

On the other hand, a similar operation is performed when the left contact detector is turned on while reaching the destination (step 601).
~604,700.800>,.

According to this second embodiment, when the loading platform is bent at an angle within the permissible range with respect to the vehicle body (the
In the final turning position, the vehicle body directly faces the loading platform, making it possible to carry out loading and unloading operations with higher precision than in the first embodiment.

In addition, in this second embodiment, by setting the allowable turning angle θ to a large value, even when the loading platform is largely curved,
The vehicle can always be positioned directly facing the loading platform, and cargo handling operations such as loading and unloading can be performed.

(Effects of the Invention) As is clear from the description of each of the embodiments above, according to the present invention, when the loading platform or the like is bent with respect to the guide vehicle, the degree of bending is within the permissible range. If the bending level exceeds the allowable range, it will be detected and the transport vehicle will not forcefully push the cargo platform, etc. , it is possible to prohibit cargo handling operations and prevent cargo from collapsing in the future.

[Brief explanation of drawings]

Figure 1 is a claim correspondence diagram showing the configuration of the first invention of the present application, Figure 2 is a claim correspondence diagram showing the configuration of the second invention, and Figure 3 is a diagram showing the configuration of an automatic guided vehicle according to the first embodiment of the present invention. Pattern diagram,
4 and 5 are diagrams showing an example of the structure of a contact detector, FIG. 6 is a block diagram showing the electrical hardware configuration of the device according to the first embodiment of the present invention, and FIG. 7 is the software configuration thereof. 8 is an explanatory diagram illustrating the operation of the apparatus of the first embodiment. FIG. 9 is a flowchart illustrating the software configuration of the apparatus of the second embodiment. FIG. 10 is an explanatory diagram illustrating the operation of the apparatus of the second embodiment. FIG. a, e... left side contact detector, f... right side contact detector, C... straight distance measuring means d, i... stop timing control means q... turning transition control means k...・Turning angle measurement means

Claims (2)

[Claims] (1) Left and right contact detectors that are independently provided on the left and right sides of the front end of the conveyance vehicle, and are supported so that they can be retreated by the reaction force when they come into contact with an object in front; the left and right contact detectors; a straight distance measuring means that starts measurement in response to a contact detection output from one of the contact detectors; when a contact detection output is obtained from the other contact detector before the measured distance reaches an allowable value, the contact It is characterized by comprising a stop timing control means that issues a stop command in response to the detection output, and issues a stop command when the tolerance value is reached when the contact detection output is not obtained from the other contact detector. Positioning device for automated guided vehicles. (2) left and right contact detectors independently provided on the left and right sides of the front end of the transport vehicle; in response to the contact detection output of either the left or right contact detector, the contact detection side is driven; A turning transition control means for stopping the rotation of the wheel and shifting to a turning operation; A turning angle measuring means for starting measurement at the time of transition to the turning operation; When a contact detection output is obtained from a contact detector, a stop command is issued in response to the contact detection output, and when a contact detection output is not obtained from the other contact detector, when the above-mentioned tolerance value is reached. A positioning device for an automatic guided vehicle, comprising a stop timing control means for issuing a stop command.