JP4298440B2 - Tilt detection device - Google Patents

Description

The present invention relates to a tilt detection apparatus for a transported object applied to a stacker crane that takes in and out a transported object from a fixed station such as a shelf.

2. Description of the Related Art Conventionally, a stacker crane is known in which a fork is attached to an elevating carriage that can be moved up and down so that the fork can move back and forth in the longitudinal direction, and the lower surface of a transferred object is received by the fork. In the case of transferring a transfer article with such a stacker crane, techniques for detecting whether the transfer article is reliably received by a fork using sensors are disclosed in the following patent documents.
Japanese Patent Laid-Open No. 5-278812 Japanese Utility Model Publication No. 6-72924 JP-A-6-144798

  Since the stacker crane described in each of the above-mentioned patent documents has a configuration including a large number of sensors, it is inevitable that the manufacturing cost increases as compared with a configuration that does not include sensors.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an apparatus for detecting the inclination of a transferred object at a low cost, which can reliably detect the inclination of the transferred object with a minimum number of sensors and prevent the transferred object from falling over or falling off the fork. It is in.

The present invention is an apparatus for detecting a tilt of a transported object, which is provided on a stacker crane that is attached to a lift carriage that can be moved up and down so that the fork can be moved back and forth in the longitudinal direction, and that receives the lower surface of the transported object with the fork. A non-contact sensor provided on a carriage for detecting a tilt of the transferred object and sending a stop signal; and a control means for stopping the fork based on the stop signal; A lower edge projecting to both sides of the fork in the width direction of the fork is arranged so as to be able to detect each, and when at least one of the pair of non-contact sensors has not detected the transported object, the stop signal is transmitted. It is characterized by that.

Furthermore, in the apparatus for detecting the tilt of a transported object according to the present invention, the pair of non-contact sensors are attached to the lift carriage with being separated on both sides in the width direction of the fork.

According to the tilt detection apparatus for a transferred object according to the present invention, when the transferred object is inclined with respect to the width direction of the fork, the fork stops. As a result, the once-inclined transferred material is also stopped as it is, so that it is possible to prevent the inclination from increasing and falling or falling off the fork. Therefore, when such a trouble occurs, it can be dealt with only by correcting an inclined baggage by an operator or the like, so that the restoration work is extremely easy as compared with a situation in which a transported object falls or drops.

Accordingly, since the troubles as described above can be found at an early stage and the cargo handling operation of the stacker crane can be stopped immediately, prompt trouble handling by an operator or the like can be expected. In addition, since only a pair of non-contact sensors can be used to detect the tilt of the transferred object and the presence / absence of the transferred object, the manufacturing cost can be greatly reduced compared to a configuration having a large number of sensors. .

  Furthermore, according to the apparatus for detecting the tilt of the transferred object according to the present invention, the pair of non-contact sensors are attached to the lifting carriage so as to be separated from both sides in the width direction of the fork, so that the non-contact sensor collides with the transferred object. There is an advantage that troubles that cause damage will not occur. In addition, since it is not necessary to process a moving part such as a fork or to provide a wiring for transmitting a stop signal, the apparatus for detecting the inclination of the transferred object is added to an existing stacker crane with very little man-hours. be able to.

Below, the inclination detection apparatus of the conveyed product which concerns on embodiment of this invention is demonstrated based on drawing.

As shown in FIGS. 1 and 2, a stacker crane S provided with an apparatus for detecting a tilt of a transported object according to an embodiment of the present invention is configured to point a fork 2 carrying a cargo with an arrow x on an elevating carriage 1 that can be raised and lowered. The fork 2 is attached so that it can move forward and backward in the longitudinal direction, and the lower surface of the transferred object 4 is received by the fork 2.

  1 and 3, a pair of non-contact sensors 6 for detecting the lower edge portions 5 projecting to both sides of the fork 2 of the transfer object 4 and sending detection signals individually, respectively. Are arranged on both sides of the lifting carriage 1. When at least one of the pair of non-contact sensors 6 has not detected the lower edge portion 5 of the transported object 4 because the transported object 4 is inclined during the cargo handling operation, the detection signal of the non-contact sensor 6 is cut off. The fork 2 stops by (becomes off). The detailed configuration is as follows.

  The lifting carriage 1 rotatably supports a plurality of rollers 10 on both sides in the width direction indicated by the arrow y, and sandwiches a pair of masts 12 raised from the chassis 11 in the vertical direction by the plurality of rollers 10. Yes. Rails 15 are laid between a plurality of rows of storage shelves 14 constituting the autostereoscopic warehouse 13. The chassis 11 is equipped with a traveling device 16 for self-propelling along the rail 15. An arrow z in the figure indicates a vertical direction, and arrows x and y indicate a horizontal direction orthogonal to each other. The longitudinal direction, the width direction, and the vertical direction described below all correspond to the arrows x, y, and z, respectively.

  As shown in FIG. 3 and FIG. 4, the transported article 4 is placed on the storage shelf 14 in a state where both sides are supported by a plurality of flanges 141 protruding to opposite positions of the plurality of columns 140 constituting the storage shelf 14. Stored. The main body of the elevating carriage 1 is a main frame 17 spanned between a pair of masts 12 in a horizontal posture. The main frame 17 is suspended by a checker that is not shown in the figure, and is moved up and down by the checker.

  As the fork 2 moves forward and backward with respect to the lifting / lowering carriage 1, as shown in phantom lines in FIGS. 1 and 2, the fork 2 protrudes from the main frame 17 and enters one storage shelf 14, to the opposite side. It will be in the state which protrudes and enters into the other storage shelf 14, or the state accommodated inside the main frame 17. FIG. The mechanism related to the forward / backward movement of the fork 2 and the upward / downward movement of the main frame 17 and the driving source thereof described above are self-explanatory techniques and are not shown.

  FIG. 5 shows an outline of an inclination detection device E including a pair of non-contact sensors 6 and a control means 7. The pair of non-contact sensors 6 are respectively fixed to the lift carriage 1 at both sides of the fork 2 in the width direction, and the loading fork 2 enters one storage shelf 14 as described above, and the transfer stored therein At the time when the transferred object 4 is elevated while receiving the object 4, the lower edge portions 5 on both sides of the transferred object 4 are detected.

  Further, a pair of non-contact sensors 60 are arranged on the opposite side of the lift carriage 1 from the non-contact sensor 6. As described above, the pair of non-contact sensors 60 are arranged such that when the fork 2 enters the other storage shelf 14 and lifts the transported article 4 stored in the other storage shelf 14, the lower edge portions on both sides of the transported article 4. 5 is detected, and is substantially the same as the pair of non-contact sensors 6. Therefore, description of the operation | movement which concerns on this is abbreviate | omitted.

  Although not shown in the figure, the control means 7 is mainly composed of a CPU that performs arithmetic processing by calling a program written in a memory or the like in a timely manner. When the stop signal is input to the control means 7, the control means 7 controls, for example, a solenoid switch shown in the figure as SW1 and SW2, and is responsible for the forward / backward movement of the fork 2 and the lifting / lowering movement of the lifting carriage 1. The power supplied to the drive source can be cut off, and these operations can be stopped immediately.

According to the apparatus for detecting the inclination of the transferred object provided in the stacker crane S described above, as shown in FIG. 3, when the transferred object 4 stored in the storage shelf 14 is elevated by the fork 2 or elevated. In the process of being pulled out from the storage shelf 14 toward the elevating carriage 1 as it is, the transported material 4 is inclined in the width direction with respect to the fork 2 due to the center of gravity of the transported material 4 being offset, in other words. When the transported material 4 is inclined with respect to the fork 2 and one side of the transported material 4 is lifted from the fork 2, either one of the pair of non-contact sensors 6 (the right side in the figure) is not contacted. The sensor 6 does not detect the transferred material 4.

  Thereby, the control means 7 recognizes that the detection signal of one non-contact sensor 6 is cut off. And since the advancing / retreating operation of the fork 2 is immediately stopped, the once-inclined transported object 4 is also stopped as it is. Therefore, the inclination of the transferred material 4 increases, and the transferred material 4 does not fall over or fall off from the fork 2. At this time, in order to notify the operator or the like of the stop of the fork 2, the control means 7 may emit a warning sound from a buzzer or the like based on the stop signal.

  In the above description, one of the non-contact sensors 6 on the right side in the figure is suggested as one non-contact sensor 6. However, when the left side of the transported object 4 rises, the non-contact sensor 6 on the left side in the figure sends a stop signal. It will be.

  Further, when the non-contact sensor 6 has not detected the lower edge portion 5 of the transferred object 4, the non-contact sensor 6 sends an undetected signal (turns on), so that the control means 7 moves the fork 2 back and forth. You may comprise so that it may stop. That is, the control means 7 performs the advance / retreat operation of the fork 2 based on the logical product (0) of the detection signal (1) or the non-detection signal (0) of the transfer object 4 individually sent from the pair of non-contact sensors 6. Stop.

  In addition, the range detected by the pair of non-contact sensors 6 is limited to the lower edge portion 5 of the transported article 4 facing the lifting carriage 1 side in the above description for the following reason. That is, even if the non-contact sensor 6 is set so as to detect the upper part of the transferred material 4, the above effect can be achieved. However, since the transferred material 4 has a specific height dimension depending on the type, There is a possibility that the non-contact sensor 6 cannot detect the transfer object 4 having a small size. Therefore, if the package 4 of the transported object 4 is focused on the point that the load 40 is placed on the pallet P, and the non-contact sensor 6 detects the lower edge portion 5 of the transported object 4, it is reliable. In addition, the presence or absence of the pallet P can be detected. Thereby, misidentification of the non-contact sensor 6 can be prevented.

  As the non-contact sensor 6, it is desirable to apply a distance-limited photosensor that can limit the detection region. For example, what irradiates infrared rays in the lower edge part 5 of the both sides of the transfer material 4 and recognizes the presence or absence of reflection of this infrared rays is mentioned. Even if the infrared rays are reflected by the lower edge portions 5 on both sides, such a distance limited type optical sensor detects the lower edge portions 5 on both sides if the lower edge portions 5 on both sides are out of a predetermined distance range. There is nothing to do.

  Therefore, when the transported object 4 is received by the fork 2, if it is too close to the lifting carriage 1 or if it is too far away, it can recognize this and send a stop signal. As described above, not only the vertical tilt with the fork 2 as an axis, but also the horizontal tilt of the transported material 4 that may occur when the transported material 4 slides on the fork 2 can be detected.

It should be noted that the present invention can be implemented in a mode in which various improvements, modifications, or variations are added based on the knowledge of those skilled in the art without departing from the spirit of the present invention. For example, as shown in FIG. 1, a pair of non-contact sensors 6 disposed at both ends of the lifting carriage 1 may be brought close to the fork 2 as shown in FIG. 6 . This is due to the following reason.

  That is, at the both ends of the lifting carriage 1, the lower part 5 of the transported object 4 is lifted by only slightly tilting the transported object 4, so that the tilt of the transported object 4 can be detected relatively sensitively. However, in consideration of the case where the size of the transferred object 4 is small and the lower edge portions 5 on both sides thereof do not reach the both ends of the lifting carriage 1, the presence or absence of this can be reliably recognized even when the size of the transferred object 4 is small. I am planning.

  By applying the present invention to a stacker crane that is operated unattended, it is possible to detect the falling of the transferred material and prevent the transferred material from being overturned in the process of loading and unloading the transferred material from a fixed station such as a shelf. be able to.

The perspective view which fractured | ruptured partially the stacker crane which provided the inclination detection apparatus of the conveyed product which concerns on embodiment of this invention. Sectional drawing of the automatic warehouse which applied the stacker crane provided with the inclination detection apparatus of the conveyed product which concerns on embodiment of this invention. (A) is a side view for explaining the operation of a stacker crane provided with a device for detecting the inclination of a transferred object according to an embodiment of the present invention, (b) is a front view thereof, and (c) is a state in which the transferred object is inclined. The side view to represent. 1 is an overall perspective view of an automatic warehouse to which a stacker crane provided with a tilt detection device for a transferred object according to an embodiment of the present invention is applied. The block diagram showing the outline which applied the inclination detection apparatus of the conveyed product which concerns on embodiment of this invention to the stacker crane . The front view showing the modification of the inclination detection apparatus of the conveyed product which concerns on embodiment of this invention.

1: Lifting carriage 2: Fork 4: Transfer object 5: Lower edge 6, 60: Non-contact sensor 7: Control means E: Inclination detector for transfer object S: Stacker crane

Claims (2)

An apparatus for detecting a tilt of a transported object, which is attached to a lift carriage that can be moved up and down so that the fork can be moved back and forth in the longitudinal direction, and is provided on a stacker crane that receives the lower surface of the transported object with the fork,
  A non-contact sensor that is provided on the lifting carriage and detects a tilt of the transported object and sends a stop signal; and a control unit that stops the fork based on the stop signal;
  A pair of the non-contact sensors are arranged so as to be able to detect lower edge portions of the transported object that project to both sides in the width direction of the fork, respectively, and at least one of the pair of non-contact sensors does not detect the transported object. An apparatus for detecting a tilt of a transferred object, wherein the stop signal is transmitted at the time of detection. The apparatus according to claim 1 , wherein the pair of non-contact sensors are attached to the lift carriage so as to be separated from both sides in the width direction of the fork.

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