JP2003237908A - Stacker crane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stacker crane which can collectively carry a plurality of articles and transfer them to/from a station at a high speed. <P>SOLUTION: An elevating/lowering base having a slide fork 12 and a turntable and a plurality of elevating/lowering shelves are provided along a frame 8 of the stacker crane 2. In addition, a conveyor 22 which can deliver articles to/from the elevating/lowering shelves 20 and also deliver articles to/from the station is provided. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stacker crane used in an automatic warehouse or the like, and more particularly to a stacker crane capable of transporting many articles at once.

[0002]

2. Description of the Related Art Stacker cranes are used as transfer devices in automated warehouses, and travel along traveling rails to elevate an elevating table equipped with transfer means along a mast to move between racks and loading / unloading stations. Transfer the article. As a general rule, the number of articles that can be carried at the same time is one, and even with a twin fork (equipped with two sets of transfer means), the number of articles is two. For this reason, the conventional stacker crane is not suitable for collectively carrying a large amount of articles.

[0003]

SUMMARY OF THE INVENTION A basic object of the present invention is to make it possible to collectively convey a plurality of articles and to shorten the cycle time of a stacker crane. An additional object of the invention of claim 2 is to shorten the transfer time to and from the station and further improve the transfer capability. Claim 3
Another object of the present invention is to provide racks on both sides of the traveling path of the stacker crane so that the stacking capacity can be increased.

[0004]

The stacker crane according to the present invention is provided with a transfer means and is provided with an elevating platform that can be raised and lowered along the mast, and a plurality of temporary storage shelves are provided along the height direction of the mast. In addition, articles can be exchanged between the elevating table and the temporary shelf (claim 1).

Preferably, the plurality of temporary storage shelves are connected by a flexible suspending member so that the temporary storage shelves can be moved up and down along a mast, and the temporary storage shelves can pass vertically. The space is provided so that the lower side of the conveyor is a space for densely arranging the temporary storage shelves and making them stand by (claim 2).

Further, preferably, the rows of the elevating table and the temporary storage shelves are arranged substantially parallel to the traveling direction of the stacker crane, and the transfer direction of the transfer means is substantially 90 °.
Means for converting are provided on the lift (claim 3).

[0007]

According to the present invention, by means of the transfer means provided on the lifting table, the articles are transferred from the rack or the receiving station to the stacker crane, and the articles are stored on the temporary shelf from the lifting table. , Transfer by stacker crane. When unloading an article, the transfer means of the lifting platform is used to unload the article from the temporary shelf to a rack, a loading / unloading station, or the like. According to the present invention, since a plurality of articles can be conveyed at once by the stacker crane, the cycle time per article can be shortened. In addition, since the weight of the time required for the stacker crane to travel is small in the cycle time per article, the cycle time does not increase much even if the travel distance of the stacker crane is increased. Therefore, it is possible to increase the size of the automated warehouse (Claim 1).

The transfer to and from the station or the like may be entirely carried out by an elevating table, but this is inefficient.
For example, the transfer to and from the station comprises three steps of moving the elevator up and down to the height of the station, transferring and elevating the elevator to the temporary shelf. On the other hand, according to the second aspect of the present invention, since the temporary storage shelf is provided with a conveyor for exchanging articles by allowing the temporary storage shelf to move up and down and passing the transport surface up and down, the temporary storage shelf serves as the conveyor. When passing over, the articles on the conveyor can be transferred to the temporary shelf, and when passing over the conveyor, the articles on the temporary shelf can be transferred to the conveyor. A space for arranging the temporary storage shelves densely and waiting for the temporary storage shelves is provided below the conveyor, and the temporary storage shelves for unloading articles onto the conveyor are made to wait in this space.

Therefore, in the invention of claim 2, the two steps of raising and lowering the temporary shelf to transfer the article between the conveyor and the conveyor and transferring the article between the conveyor and the station are performed. By doing so, a large number of articles can be efficiently put in and out of the station. It should be noted that it is not necessary to use a conveyor for all entry and exit to and from the station. For example, a conveyor may be used only during exit and exit, and a lifting platform may be used during entry and exit. In this case, for example, the temporary storage shelf is raised before the start of storage, and every time an article is stored on the elevating table, the elevating table is elevated and transferred to the temporary storage shelf. With this configuration, it is not necessary to raise the temporary storage shelf that has stored the articles and has increased weight, and the motor for raising and lowering the temporary storage shelf can be reduced.
In addition, although such warehousing takes time, the warehousing itself does not have to be urgent in many cases. On the other hand, in the case of warehousing, urgency is generally required, and when the temporary storage shelf is lowered at the time of storage and is sequentially paid out to the station via the conveyor, it is possible to promptly output the product and the motor required for raising and lowering the temporary storage shelf is used. The output may be small.

According to the third aspect of the present invention, means for changing the transfer direction of the transfer means by approximately 90 ° is provided on the lift table, and the temporary shelf is located in front of the lift table when viewed from the traveling direction of the stacker crane. Place it in the rear. Therefore, when viewed from the lifting platform, transfer can be performed between the left and right sides in the traveling direction, and the racks can be arranged on both sides in the traveling direction of the stacker crane.
Further, when exchanging articles between the temporary storage shelf and the elevating table, the transfer means that has pulled the article from the rack or the like is turned on the elevating table by approximately 90 °, and then the article is transferred to the temporary storage shelf by the transfer means. Good. On the contrary, in transferring an article from the temporary shelf to the lifting table, the transfer direction of the transfer means of the lifting table is changed by about 90 °, and the article is transferred from the temporary shelf to the transfer means.
Then, the transfer direction of the transfer means is changed again by 90 °, and the transfer means may be transferred to a station, a rack, or the like (claim 3).

[0011]

[Embodiment] A stacker crane 2 of the embodiment shown in Figs.
Indicates. In these figures, 4 is a trolley provided in the lower part of the stacker crane, other than this, a trolley may be provided in the upper part, and 6 is a traveling rail. Reference numeral 8 denotes a frame, which has a gate shape composed of two columns here, but the structure itself is arbitrary. Reference numeral 10 is an elevator, which is elevated along a column 8a of the frame 8 and a slide fork 12 is provided on an elevator mount 16 via a turntable 14. Note that instead of the slide fork 12, other transfer means such as a chain may be used, and the turntable 14 may be one that can change the transfer direction of the slide fork 12 by 90 °, for example. Reference numeral 18 denotes a lifting motor for the lifting table 10.

A plurality of elevating shelves 20 are provided on a pillar 8b on the opposite side of the gate-shaped frame 8 so that the shelves can be moved up and down along the pillar 8b of the frame 8, and 22 is a conveyor, here a roller conveyor. Can be a chain conveyor,
It is provided at a height where articles can be exchanged with the loading / unloading station 34. 24 is a lifting guide for the lifting shelf 20, and 25
Is an article on the elevating shelf 20, the elevating motor 26 connects the elevating shelves 20 of a plurality of shelves with a suspending member to elevate and lower, and 28 is a counterweight of the elevating shelf 20. The elevating shelves 20 are, for example, two vertical comb teeth and are connected to each other by a flexible suspending member such as a chain or a rope.

The elevating shelf 20 receives the article 25 from the conveyor 22 by passing the conveying surface of the conveyor 22 upward, and unloads the article 25 to the conveyor 22 by passing the conveying surface of the conveyor 22 downward. To do. Then, the space below the conveyor 22 serves as a standby space for the elevating shelves 20, and the elevating shelves 20 are arranged densely, that is, arranged closer to each other than on the conveyor 22 so that they are almost stacked and stand by.

FIG. 3 shows the relationship between the conveyor 22 and the elevating shelves 20. The conveyor 22 is, for example, a roller conveyor, and the spaces 39, 3 inside the outer rollers 38, 38.
The elevating shelf 20 can pass through 9, and the elevating shelf 20 is moved up and down by a lifting motor via a suspending member 40 such as a chain.
Returning to FIGS. 1 and 2, 30 is a traveling motor, 32 is a control panel, 34 is a loading / unloading station, particularly a loading / unloading station here, and 36 is a pusher for loading articles from the roller conveyor of the station 34. It is for pushing out to the conveyor 22 of the stacker crane 2. Instead of the pusher 36, any means can be used as long as it can transfer the articles on the station 34 onto the conveyor 22. Here, the elevating shelf 20 is in the shape of two vertical comb teeth, and the transfer means is the slide fork 12 that passes between the two vertical comb teeth. If the mounting means is in the shape of a large number of vertical comb teeth corresponding thereto, it becomes possible to handle small articles.

FIG. 4 shows the construction of the automatic warehouse 42 using the stacker crane 2. A pair of racks 46 and 46 are provided on both sides of the traveling rail 6, and a pair of stations 3 are provided.
4, 44 are provided. Then, at the time of storage, the stacker crane 2 receives a plurality of articles at once until the elevating shelf 20 is full, and sequentially stores the articles from an empty shelf near (or far from) the stations 34, 44. Further, at the time of leaving the warehouse, for example, the goods requested to leave the warehouse are stored in the station 3
The racks are taken out in order from the distant (or near) shelves 4, 44 and temporarily placed until the elevating shelves are full, and when the shelves are full, they travel to the stations 34, 44 and take out continuously. At this time, when it is necessary to store the articles in a desired order, the articles to be delivered first are temporarily placed in order from the lower elevating shelf.

The operation of the embodiment will be described. When the articles are transferred from the station 34 or the like to the stacker crane 2, the articles are transferred to the conveyor 22 by the pushers 36 or the like, the elevating shelf 20 is passed over the conveying surface of the conveyor 22, and the conveyor 22 is moved to the elevating shelf 20. Transfer the goods to. Therefore 1
The time required to transfer the articles is determined by the sum of the time required to carry the articles to the conveyor 22 and the time required to pass the elevator shelf to the upper side of the conveyor 22, and a large amount of articles are loaded into the stacker crane 2 in a short time. be able to. When unloading an article to the station 44, the elevator shelf 20 is passed downward so as to traverse the transport surface of the conveyor 22, the article is transferred onto the conveyor 22, and the conveyor 2 is transferred to the station.
Carry out by 2. Therefore, one article can be carried out by the sum of the time required to carry out the article from the conveyor 22 and the time taken to pass the elevator shelf 20 through the transport surface of the conveyor 22.

The transfer table 10 is used for transferring articles between the rack 46 and the lift shelf 20, and the turntable 14 changes the direction of the slide fork 12 by about 90 °.
Articles are exchanged between the elevating shelf 20 and the elevating table 10, the direction of the slide fork 12 is changed again by 90 °, and the articles are transferred to the rack 46 or the like. Elevating table 10
If the two types of transfer means, that is, the transfer means for transferring the article to and from the rack and the transfer means for transferring the article to and from the elevating shelf 20, are provided, the turntable 14 may not be provided.

In order to shorten the cycle time, it is preferable to use the conveyor 22 to load and unload the articles at the time of loading and unloading, but if the loading speed may be slowed, before loading The elevating shelves are lifted up to, and the articles are loaded from the receiving station using the elevating table 10.
It is also possible to elevate the elevating table 10 to a desired height of the elevating shelf and reload the articles from the elevating table 10 to the elevating shelf 20. The advantage of doing this is that it is not necessary to wind up the elevating rack on which a large number of articles are placed by the elevating motor 26, so that the output of the elevating motor 26 can be reduced. The problem is that the time required for the warehousing operation becomes long.

The elevating shelf 20 can be used for various operations other than this, for example, in parallel with the traveling of the stacker crane 2, to the height position of the shelf of the rack for unloading articles next, or next. It is also possible to elevate and lower the required elevating shelves to the height position of the shelves of the rack on which the articles are loaded.

FIG. 5 schematically shows a basic operation pattern at the time of loading and unloading. For example, in the case of warehousing, an article is carried into the station 34 by a forklift or a long-distance conveyor and lifted up and down with the conveyor 22. A plurality of articles are collectively loaded on the stacker crane 2 by using the shelf 20. Next, the stacker crane 2 is run to unload the stored articles into one station 48 of the rack 46 or two stations facing each other. By doing so, it is not necessary to move the stacker crane 2 during unloading of the rack, and the lifting / lowering operation of the lifting platform 10 is simplified, and the upper and lower lifting shelves are sequentially moved to the lower lifting and lowering shelves. Alternatively, conversely, the articles may be exchanged in order from the lower elevating shelf to the upper elevating shelf. Therefore, the lifting distance of the lifting table 10 during transfer to and from the rack 46 can be reduced.

It is preferable to use the idle time of the stacker crane 2 or the like before leaving the warehouse so that the articles to be delivered are aligned in the height direction of one station or two stations facing each other. In this case, the stacker crane 2 is stopped so as to come into contact with the station that performs the unloading, and the plurality of articles are sequentially transferred to the elevating shelf 20 using the elevating table 10 when the unloading is performed.
After that, the stacker crane 2 is moved to a position in contact with the station 44 or the like, and the articles are unloaded using the lowering of the elevating shelf 20 and the payout from the conveyor 22.

In the embodiment, the elevating table 10, the elevating shelf 20 and the conveyor 22 are provided in the stacker crane 2, but a modified example of a simpler structure is shown in FIG. In the stacker crane 52 of FIG. 6, a plurality of temporary storage shelves 56 are fixedly provided along the height direction of the T-shaped pillar 54 in a plan view, and an elevating table 58 provided with a slide fork 60 along the pillar 55. Raise and lower. Then, the row of the temporary storage shelves 56 and the lifting platform 58 is arranged so as to face a direction substantially perpendicular to the traveling direction of the stacker crane 52, and the rack 46 is provided on the side in contact with the lifting platform 58, and is close to the temporary storage rack 56. There is no rack on the side. 6
Reference numerals 1 and 62 are traveling rails.

In the modified example of FIG. 6, articles are exchanged with a rack or a station by using an elevating table 58, and the elevating table 58 is moved up and down along a pillar 55 to make a plurality of temporary storages from the elevating table 58. The articles are stored in the shelves 56, and the articles are taken out from the temporary storage shelves 56 by the elevator 58.

In the embodiment, the stacker cranes 2, 52
Since a plurality of articles can be accommodated in and transported in a batch, the ratio of the traveling time of the stacker crane 2 to the time required to transport the articles can be reduced. Therefore, the running rail 6
Even if the length is increased and a long automatic warehouse is provided, the time required for loading and unloading does not extend much. In addition, in the case of an automatic warehouse with a normal traveling length, the cycle time for loading and unloading can be shortened.
Further, by using the combination of the elevating shelf 20 and the conveyor 22, it is possible to transfer articles to and from the station extremely efficiently, and further reduce the cycle time. In the embodiment, only one conveyor 22 is provided, but in case of providing a plurality of stations with different height levels,
A plurality of conveyors 22 may be provided at different height levels.

[Brief description of drawings]

FIG. 1 is a perspective view of a stacker crane according to an embodiment.

FIG. 2 is a side view of the stacker crane of the embodiment.

FIG. 3 is a plan view showing the relationship between the conveyor and the lifting shelves in the stacker crane of the embodiment.

FIG. 4 is a plan view showing a layout of an automated warehouse using the stacker crane of the embodiment.

FIG. 5 is a plan view schematically showing the operation of an automated warehouse using the stacker crane of the embodiment.

FIG. 6 is a front view showing a layout of an automated warehouse using a modified stacker crane.

[Explanation of symbols]

2 stacker crane 4 dolly 6 running rails 8 frames 10 Elevating platform 12 slide forks 14 turntable 16 Lifting table mounting part 18 Lifting motor 20 Elevating shelves 22 Conveyor 24 Lift guide 25 articles 26 Lifting motor 28 counterweight 30 traveling motor 32 control panel 34,44 stations 36 pushers 38 Outer roller 39 spaces 40 Suspension material 42 automated warehouse 46 racks 52 Stacker crane 54,55 columns 56 Temporary shelf 58 Lifting platform 60 slide forks 61,62 traveling rail 48 stations

Claims (3)

[Claims] 1. A lift provided with transfer means and movable up and down along a mast is provided, and a plurality of temporary storage shelves for articles are provided along the height direction of the mast, and the lift and the temporary storage are provided. A stacker crane that allows items to be exchanged with a shelf. 2. A conveyor is provided which connects the plurality of temporary storage shelves with a flexible suspending member so that the temporary storage shelves can be moved up and down along a mast, and the temporary storage shelves can pass vertically. The stacker crane according to claim 1, wherein the lower side of the conveyor is a space for arranging the temporary storage shelves densely and making them stand by. 3. A row of the elevating table and the temporary shelves is arranged substantially parallel to the traveling direction of the stacker crane, and the means for changing the transfer direction of the transfer means by about 90 ° is moved up and down. The stacker crane according to claim 1 or 2, wherein the stacker crane is provided on a base.