JPH0680206A - Suspension device for stacker crane - Google Patents

Abstract

PURPOSE:To determine a suspension position for a stacker crane in response to dislocation at a frontage. CONSTITUTION:Each pillar 6 of a shelf set 5 is zigzagged, the frontage of each stage 1, 2 and 3 composed of the sets of cants 7 is thereby slipped off along the running direction of a stacker crane 1. A shielding plate 8 the upper section of which is formed into a comb teeth shape is provided for the front face of the frontage, and since the center lines C1, C2 and C3 of each stage coincide with the comb tooth at the center, the comb tooth at the left to the center and the comb tooth at the right to the center respectively, the stacker crane 1 can thereby be suspended at a proper article delivery position by detecting the ON/OFF operations of a photo electric sensor which interchangeably appears as the stacker crane 1 is run.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stacker crane stopping device capable of coping with distortion in the traveling direction of a stacker crane at the front of an automatic warehouse.

[0002]

2. Description of the Related Art A stacker crane for loading and unloading work in an automated warehouse travels and goes up and down in front of a plurality of frontages arranged in a matrix. The stacker crane lift is provided with a fork for transferring articles to and from the frontage. When delivering goods, stop the elevator at a fixed stop position with respect to the frontage to be handed over, and the articles will hit the components of the frontage, causing a load collapse and other obstacles. You have to be able to do the delivery work without any trouble. Therefore, a shield plate is arranged on the floor surface, and the stop position is determined by detecting the shield plate by a shield type photoelectric sensor provided on the stacker crane side.

[0003]

According to the method of determining the traveling stop position based on the position of the shielding plate arranged on the floor, there is no problem when the frontages are lined up correctly,
In reality, the tilt of the columns causes the shelves to be distorted. Therefore, it was necessary to manufacture the frontage larger than the articles to be stored to increase the clearance, or to change the traveling stop position of the stacker crane for each frontage by finely adjusting the traveling distance using an encoder together. . The larger the clearance, the larger the dead space on the shelf,
If the travel stop position is changed for each frontage, the control method for controlling the stop position in the travel direction becomes complicated, and the control device and the position detection device have to be large in scale.

Therefore, an object of the present invention is to provide a stacker crane stopping device which can reduce the clearance of the frontage and can control the traveling of the stacker crane by a simple control method without causing a load collapse or the like.

[0005]

In order to achieve the above object, the present invention is a stop device for a stacker crane which detects a shield plate arranged on a floor surface by a shield type photoelectric sensor to determine a stop position. Then, the shielding plate is formed in a comb-like shape in which the ON / OFF of the photoelectric sensor alternately appears according to the traveling of the stacker crane to form the stacker crane stopping device.

[0006]

Since the present invention has the above-mentioned structure, it has the following effects.

In the stacker crane stopping device according to the present invention, the shield plate detected by the photoelectric sensor has a comb-like shape, and the optical axis of the photoelectric sensor hits the teeth of the comb tooth and is interrupted as the stacker crane travels. Since it passes between the teeth, ON and OFF are alternately repeated. Therefore, compared to one flat shield plate, several different stop positions are displayed in stages.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments shown in the drawings will be described below.

FIG. 1 is a front view showing a part of an automatic warehouse to which an embodiment of a stacker crane stopping device according to the present invention is applied.

In FIG. 1, the stacker crane 1 is shown in FIG.
As the vehicle runs in the left-right direction, the elevator platform 2 moves up and down along the masts 3, 3. The lifting table 2 is provided with a fork 4 for transferring articles. The shelf rack 5 is composed of a plurality of pillars 6 and 6 that are continuously erected, and a plurality of canches 7 that project between the pillars 6 and 6, respectively. Adjacent canches 7, 7 and pillars 6, 6 form a frontage on which an article W is placed.
A space is provided between the canches 7, 7 so that the fork 4 can scoop the article W from below.

The stacker crane 1 can be stopped at a fixed position by detecting a plurality of shield plates 8 arranged in front of each frontage with a shield type photoelectric sensor 9. The photoelectric sensor 9 is attached so that its optical axis coincides with the fork 4, that is, the center line of the article W in the drawing.

The shielding plate 8 has a flat plate-like upper portion with a comb-like shape, so that the stacker crane 1 moves.
As the locus of the optical axis of the photoelectric sensor 9 moves as shown by B, the optical axis of the photoelectric sensor 9 is interrupted by the comb-shaped portion, while the comb-shaped portion can pass through, so that the photoelectric sensor 9 repeats ON and OFF alternately.

Each pillar 6 of the rack 5 is not actually perpendicular to the floor surface, but is usually inclined or bent as shown in FIG. 1 (exaggerated in the drawing). Shown). In FIG. 1, the pillars 6 are bent alternately to the left and right as they go upward, and when the frontage of the first stage constituted by the lowest cantileces 7a, 7a is used as a reference, the second stage cantilever 7 is used.
The frontage of b and 7b is shifted to the left in the figure, and the cantilever 7 in the third stage
c and 7c are displaced to the right in the figure.

The center lines of the steps are respectively C1, C2, C
3 and extending downwards, the center line C1 is the center comb tooth of the shield plate 8, the center line C2 is the center left comb tooth, and the center line C3 is the center right comb tooth. Reach

Therefore, when the stacker crane 1 transfers articles W to and from the frontage of the first stage, assuming that the stacker crane 1 travels from the right direction, the photoelectric sensor 9 is once turned on and then turned off. Will be ON again
Then, the stacker crane 1 can be stopped at an appropriate article transfer position between the stacker crane 1 and the frontage of the first stage by stopping the stacker crane 1 when it is turned off and turned on next.

Similarly, when transferring to and from the frontage of the second stage, when the photoelectric sensor is turned off for the second time, it is turned off for the fourth time with the frontage of the third stage. If they are stopped at the same time, they can be stopped at appropriate article transfer positions. The same applies when driving from the left.

Therefore, after the automatic warehouse is installed and before the operation is started, the deviation of each frontage is measured, and the comb teeth or the interdental teeth matching the center line of each frontage are registered in the stacker crane controller. ON / OFF of photoelectric sensor 9
Thus, it is possible to detect an appropriate article transfer position.

As described above, according to the stacker crane stopping device of this embodiment, since the shielding plate 8 has a comb-like shape, the photoelectric sensor 9 is turned on as the stacker crane 1 travels.
By repeating N and OFF, the position of the stacker crane 1 in the traveling direction can be detected stepwise.

The embodiment of the present invention has been described above.
It is needless to say that the present invention is not limited to the above-mentioned embodiments and can be appropriately modified within the scope of the gist of the present invention.

[0020]

As described above, according to the stacker crane stop device of the present invention, the article transfer position for each frontage can be detected by turning on and off the photoelectric sensor, so that the frontage clearance can be minimized and dead. Space can be reduced. The control structure is also simple,
Does not require special detectors or large scale control equipment.

[Brief description of drawings]

FIG. 1 is a plan view showing a part of an automatic warehouse to which an embodiment of an automatic warehouse loading / unloading control apparatus according to the present invention is applied.

[Explanation of symbols]

 1 Stacker crane 4 Fork 5 Shelf 6 Pillar 7 Cantilever 8 Shielding plate 9 Photoelectric sensor W Article C1, C2, C3 Center line

Claims (1)

[Claims] 1. A stop device for a stacker crane, which detects a shield plate arranged on a floor surface by a shield type photoelectric sensor to determine a stop position, wherein the shield plate turns on the photoelectric sensor as the stacker crane travels. A stacker crane stopping device having a comb-like configuration in which OFF is alternately seen.