JPH07196105A - Position detector of slide fork in automatic warehouse - Google Patents

Abstract

PURPOSE:To facilitate maintenance and detection of detectors by providing the bracket of a slide fork which exposes the detectors on the right and left sides. CONSTITUTION:Two front and rear detectors 21 are attached to a bracket 20 on one side which projects on the right and left sides of a slide fork 17 in such a way that they are arranged in parallel in the forward and backward directions and do not protrude from a top face of the slide fork 17. The detectors 21 are provided with a light projector 24 and a light receiver 25 which oppose mutually across a clearance 22 through which a detected piece passes in their main bodies 23 in the shape of U character. A detected piece 27 which is longer than an interval of the light projector 24 of the front and rear detectors 21 is provided in a position where it fits in the clearance 22 through which the detected piece passes of the detectors 21 on a bottom face of an object support member. A bracket 28 having a horizontal section 28a is provided on an ascent and descent base 16, and the detected piece 27 is provided on a bottom face of a part which opposes to the bracket 20 of the horizontal section 28a of the bracket 28 in such a way that it fits in the clearance 22 through which the detected piece passes. The position of the slide fork is detected by these two detectors 21 and the detected piece 27.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slide fork position detecting device for an automatic warehouse.

[0002]

2. Description of the Related Art Conventionally, the following type of position detecting device for a slide fork of an automatic warehouse of this type has been known. That is, a base provided on the lifting platform of the stacker crane, a middle (intermediate sliding body) provided on the base so as to be slidable back and forth, a slide fork provided on the middle so as to be slidable back and forth, and a middle operation. A device, an interlocking mechanism that slides a slide fork in the same direction as the middle in conjunction with the movement of the middle, four limit switches provided on the upper surface of the base in the left-right direction, and each limit in the middle. It has a dog (cam) that operates a limit switch provided corresponding to the switch, and the position of the slide fork (specifically, the middle position), that is, whether the slide fork projects forward,
Whether it is protruding later or located in the center,
It is known that the four limit switches are detected by the "ON" and "OFF" states of the limit switch to control the sliding / stopping of the slide fork.

[0003]

Disadvantages of the Prior Art The conventional position detecting device has the following disadvantages. Since the limit switch was installed in the base and the dog (cam) was installed in the middle, that is, the limit switch and dog (cam) were stored in a narrow space between the base and the middle, maintenance and inspection of them was performed. It had the drawback of being difficult.

[0004]

[Means for Solving the Disadvantages] The present invention adopts the following means in order to eliminate the above disadvantages. The present invention is provided on the left or right side of an intermediate sliding body that is slidably mounted back and forth on a lifting platform of a stacker crane or on the left or right side of a slide fork that is slidably mounted back and forth on the intermediate sliding body. The bracket, the at least two detectors provided side by side in the front-rear direction on the bracket, and the detected pieces provided on the article storage rack and the lifting table.

[0005]

The present invention has the following functions. The position of the slide fork can be detected by the cooperation of at least two detectors and the detected pieces provided on the article storage rack and the lifting table. Since the detector is mounted on the bracket that is exposed to the left and right sides, it is easy to perform maintenance and inspection of the detector.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the embodiments shown in the drawings. In this specification, the front means the lower side of FIG. 1, the rear means the upper side of FIG. 1, the left means the left side of FIG. 1, and the right means the right side of FIG.

A pair of front and rear rack devices 1 are erected on the floor so as to open the stacker crane passage 10. The rack device 1 includes a large number of front columns 2 arranged at right and left at predetermined intervals, rear columns 2 arranged behind the front columns 2 with a predetermined space therebetween, and front and rear columns 2. Has a large number of article support members 4 provided at predetermined intervals in the height direction, and the article storage shelves 3 are formed by a pair of left and right article support members 4 that face each other without interposing the columns 2.
Is configured. A fork passage gap 5 is provided between the pair of left and right article support members 4 to allow a slide fork 17 to be described later to move in the vertical direction. The access ports 6 of the article storage shelves 3 of the front and rear rack devices 1 face each other.

On the left side of the rack device 1, there is provided a loading / unloading roller conveyor 8 whose carrying direction is left and right. The rack device 1 for the loading / unloading roller conveyor 8
A known article elevator (not shown) is provided on the side.
This article elevator includes a lift table that can be raised and lowered by a known lift device below the rollers of the loading / unloading roller conveyor 8,
The elevator table is provided upright and has a pair of bearing frames located between the rollers of the loading / unloading roller conveyor 8. This article lifter forms a fork insertion gap between the conveying surface of the loading / unloading roller conveyor 8 and the bottom surface of the article W by lifting the article W by the support frame, or the slide fork 1 by the support frame in the raised position.
The article W is received from the article 7 and then descends to have the function of lowering the article W on the loading / unloading roller conveyor 8.

A pair of upper and lower guide rails 11 are arranged in the stacker crane passage 10 so that the longitudinal direction thereof is oriented in the left-right direction, and the stacker crane 13 is guided by these guide rails 11 so as to be movable left and right. , This stacker crane 13 has a traveling carriage 14
And a lift 16 that can be lifted and lowered on a mast 15 provided on the traveling carriage 14, and a slide fork 17 that is provided on the lift 16 so as to be horizontally slidable in the front-rear direction by a well-known forward / backward mechanism. is doing. The known sliding mechanism has a base provided on the lift table 16 and an intermediate sliding body (middle) slidably mounted on the base and on which a slide fork 17 is slidably mounted. When the intermediate sliding body moves with respect to the base, the slide fork 17 is configured to move in the same direction and the same amount with respect to the intermediate sliding body in conjunction with the movement. As is known, the slide fork 17 pulls the article W into the lift table 16 by performing an operation of projecting the article W downward, lifting the article W by raising the lift table 16 and retreating to the lift table 16 side. The article W can be unloaded onto the article storage shelf 3 or the like by the reverse operation.

Horizontally extending brackets 20 are provided on the left and right sides of the slide fork 17 in the front-rear direction. One of the brackets 20 is aligned in the front-rear direction and does not protrude from the upper surface of the slide fork 17. Then, the front and rear two detectors 21 are attached. Each of these detectors 21 has a U-shaped main body 23 having a detection piece passage gap 22, and a projector 24 and a light receiver 25 that face each other across the detection piece passage gap 22. At a position where it is fitted in the detection piece passage gap 22 of the detector 21, a detection piece 27 having a front-rear length longer than the distance between the front and rear light projectors 24 of the detector 21 is provided on the lower surface of the article support member 4. It is provided. The lifting table 16 is provided with a bracket 28 having a horizontal portion 28a located at a position lower than the upper surface of the slide fork 17, and the horizontal surface 28a of the bracket 28 has a portion lower surface facing the bracket 20. A detected piece 27 is provided so as to fit in the gap 22. The detected piece 27 also has a front-rear length longer than the interval between the projectors 24 of the front-rear detector 21. In addition, in order to allow the vertical movement of the lifting platform 16 when transferring the article W,
Further, at that time, the height of the detected piece 27, the height of the detected piece passage gap 22, the height positions of the light emitter 24 and the light receiver 25 are adjusted so that the detected piece 27 does not come off from the light projector 24. Has been done.

The slide fork 17 can be caused to perform the operation control as shown in the timing chart of FIG. 5 by the cooperation of the two detectors 21 and the detected piece 27 provided on the article support member 4 and the lift table 16. I can. That is, when the slide fork 17 is located at the center in the front-rear direction (directly above the lift table 16), the projectors 2 of the front and rear detectors 21 are arranged.
The light of No. 4 is blocked by the detected piece 27 of the lift 16. In this state, when a signal is issued that causes the slide fork 17 to project forward, the slide fork 17 initially projects at high speed and later at low speed. In the process, the light from the projector 24 of the front detector 21 is blocked by the detected piece 27 of the article support member 4, and then the light of the projector 24 of the rear detector 21 is detected piece 2 of the article support member 4.
Blocked by 7. After the light from both projectors 24 is blocked in this way (see point a in FIG. 5), the timer is operated for a predetermined short time, and after that time elapses, the slide fork 17
To stop. In this way, the slide fork 17 can be stopped at a predetermined position (see the line a in FIG. 5). When a signal for retreating the slide fork 17 is issued from the above-mentioned protruding state, the slide fork 17 initially retreats backward at a high speed and later at a low speed. In the process, the light from the projector 24 of the detector 21 on the rear side is blocked by the detected piece 27 of the lift 16 and then the detector 2 on the front side.
The light from the first light projector 24 is blocked by the detected piece 27 of the lift 16. After the light of both projectors 24 is blocked in this way (see point b in FIG. 5), the timer is operated for a predetermined short time, and after that time, the slide fork 17 is stopped. In this way, the slide fork 17 can be stopped at the center in the front-rear direction (see line B in FIG. 5). The same operation as described above is performed when projecting to the rear and when retreating from the rear (see line C and line D in FIG. 5). In the figure, points c and d are timer operation start points. As described above, in this embodiment, the position detection required for stopping the slide fork 17 can be performed only by the two detectors 21.

In FIG. 6, the rack device 1 is provided with two article storage shelves 3 in the depth direction of the article storage shelves 3 on the stacker crane passage 10 side and the article storage shelves 3 farther from the stacker crane passage 10. A modified example is shown. Detected pieces 27 are provided on the article support members 4 of both article storage shelves 3. In this modification, the stacker crane passage 1
When the article W is transferred to and from the article storage shelf 3 located farther from 0, when the slide fork 17 is projected, the detected piece 27 of the article storage shelf 3 on the stacker crane passage 10 side is detected forward and backward. After the deceleration, the projectors 24 of the two detectors 21 are arranged so that deceleration is performed after the detector 21 has passed.
When the light is blocked by the piece to be detected 27, the timer is activated, while on the other hand, when retracting to the lift table 16 side, the article storage shelf 3 on the stacker crane passage 10 side
After deceleration, the projectors 2 of both detectors 21 are arranged so that deceleration is performed after the front and rear detectors 21 pass through the detected piece 27 of
The timer may be activated after the light of No. 4 is blocked by the detected piece 27 of the lift 16.

A bracket 20 is provided on the intermediate sliding body (middle) of the slide fork 17, and the bracket 2
The detector 21 may be attached to 0. Also,
A detector for detecting that the slide fork 17 is located in the center of the lift table 16 in order to detect the position of the slide fork 17 more accurately when the slide fork 17 is restored to an emergency stop due to some trouble. May be added.

[0014]

Advantages of the Embodiment The above embodiment has the following advantages. Since the detector 20 is not in contact with the detected piece 27, there are few failures.

[0015]

The present invention has the following effects due to the above-mentioned configuration. The position of the slide fork can be detected by the cooperation of at least two detectors and the detected pieces provided on the article storage rack and the lifting table. Since the detector is mounted on the bracket that is exposed to the left and right sides, it is easy to perform maintenance and inspection of the detector. In the conventional device, the rack device is provided with two article storage shelves in the depth direction of the article storage shelves on the side of the elevator and the article storage shelves farther from the elevator, and the protrusion amount of the slide fork corresponds to the shelf. However, in the case of the so-called double-reach type, two limit switches are required, but in the present invention, as shown in the modified example, the one farther from the lifting platform is used. It suffices to provide the detected piece on the article storage rack.

[Brief description of drawings]

FIG. 1 is a partially omitted simplified plan view showing an embodiment of the present invention.

FIG. 2 is an enlarged view of part A of FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is a timing chart of the operation of the slide fork.

FIG. 6 is a side sectional view of a main part showing a modified example.

[Explanation of symbols]

 13 Stacker crane 16 Lifting platform 17 Slide fork 20 Bracket 21 Detector 27 Detected piece

Claims (1)

[Claims] 1. A left or right side portion of an intermediate sliding body provided on the lifting platform of a stacker crane so as to be slidable back and forth, or a left or right side portion of a slide fork provided on the intermediate sliding body so as to be slidable back and forth. Position detecting device for a slide fork of an automatic warehouse, comprising: the bracket, the at least two detectors provided on the bracket so as to be arranged in the front-rear direction, and the detected pieces provided on the article storage rack and the elevating table.