JP2007001670A - Stocker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stocker of large size for a vessel (FOUP) in which a substrate for manufacturing semiconductor (wafer) is detachably accommodated, capable of conducting easily the taking-out of a desired FOUP existing in the stoker when a robot to transfer a FOUP from a carry-in port onto any of a number of shelves or transport the FOUP placed on the shelf to a carryout port has encountered such a situation as not able to operate normally. <P>SOLUTION: From a door 14 for shelves on one 2 of which the desired FOUP 3 to be taken out in emergency is placed, the operator takes out the desired FOUP 3 and places it on an elevating/sinking plate 12. A wire is coupled with the plate 12 and taken out to outside the stocker by operating manually a wire takeup/payoff mechanism 13. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention, for example, in a semiconductor manufacturing process, is transported by a suspended lift carriage (hereinafter referred to as an OHT carriage) and accommodates a semiconductor manufacturing substrate (hereinafter referred to as a wafer) detachably inserted therein (hereinafter referred to as a wafer). FOUP (in particular, FOUP), especially when an abnormal situation occurs where the robot that stores and removes the FOUP provided in the stocker cannot operate normally due to a power failure or other cause The processing device for taking out a desired FOUP.

In recent years, it is necessary in a series of semiconductor manufacturing equipment (hereinafter referred to as stations) that perform various surface treatments (cleaning, film formation, resist, CVD, inspection, etc.) of wafers arranged along an in-process annular track in a clean room. In order to perform an appropriate process, the FOUP containing the wafer is often transported using an OHT carriage.
The FOUP containing the wafer that has undergone such surface treatment or at least a portion of the surface treatment is identified by the information attached to the tag, and subsequent necessary surface treatment is managed by the computer based on the tag information. Is done.

At this time, each station has a different processing time depending on the type of surface treatment, and a stocker equipped with a FOUP carry-in port and a carry-out port is provided to temporarily hold the FOUP for reasons such as process time adjustment. It has been.
This stocker is equipped with a number of shelves, FOUP carry-in ports and carry-out ports, and robots (stacker cranes, transfer devices) on which FOUPs introduced from the carry-in ports are placed or transferred from the shelves to the carry-out ports. Composed of others).

In most cases, the transfer of the FOUP by the robot is appropriately performed according to the instruction of the computer, and no inconvenience is caused.
However, if a situation occurs in which the robot is not properly operated due to a power failure, a tag defect, or the like, the FOUP scheduled to perform a predetermined process cannot be transferred from the stocker to the carry-out port.
As described above, in a situation where the predetermined FOUP cannot be transferred from the inside of the stocker to the carry-out port, the predetermined FOUP must be manually moved from the inside of the stocker to a place where it can be transported by the OHT carriage.

By the way, the movement of the FOUP manually can be performed relatively easily when the number of wafers stored in the FOUP and subjected to various surface treatments is small, but in recent years, the size of the wafer has been increasing.
Therefore, it takes considerable time to manually move the FOUP from the inside of the stocker to the outside of the stocker, and if the wafer size is further increased, it is difficult to manually carry out the FOUP from the inside of the stocker. It becomes.

As a specific example of means for dealing with such a situation that FOUP and other articles in the stocker cannot be normally conveyed by the electric means, there is Patent Document 1 below.
Specifically, the technique disclosed in Patent Document 1 has a configuration as shown in FIGS. That is, in the automatic warehouse (FOUP and other article stockers) 1 shown in FIG. 1, there are a large number of article storage shelves 25, and a plurality of opposing storage units 20 are disposed between the storage units 20 of each pair. The mechanism of the stacker crane 3 having a mechanism that is supported at the upper and lower ends so as to be movable in the front-rear direction of FIG.

The stacker crane 3 includes a ladder 47 as shown in FIGS. 2 and 4. The ladder 47 not only acts to increase the rigidity of the stacker crane 3 so as to prevent the stacker crane 3 from vibrating in the traveling direction when the stacker crane 3 travels in the automatic warehouse, but also operates the stacker crane 3 for other reasons such as a power failure. When the machine stops, it is used for taking out articles by hand.
That is, for example, when the stacker crane 3 is brought into an operation stop state due to a power failure or any other cause, the articles (FOUP etc.) placed on a predetermined shelf are not waited for the repair of the stacker crane 3. 3 and 4 show a configuration relating to a means for emergency manual removal.

First, in the configuration disclosed in FIG. 3, the stacker crane 3 that moves along the traveling rail 38 (see FIG. 1) cannot move as it is because the brake 54 is operated during a power failure.
Accordingly, the brake action of the brake 54 is released by the brake release lever 54a, and the stacker crane 3 can move horizontally on the rail to the desired storage shelf position by the manual rotation of the handle 54b.

Next, with regard to the means for lowering the article 30 in an emergency of the stacker crane 3, as shown in FIGS. 4 and 5, the lifting platform 34 is moved to the height of the shelf 25 on which the emergency take-out object 30 is placed. . This operation is performed by opening the release lever of the brake 63 in FIG. 5 and manually rotating the handle 64.
Further, an article to be lifted up to a predetermined height on the ladder by the operator is placed on the elevator 34 from the shelf 25, and the elevator 34 is lowered by rotating the manual handle 64, and the article on the elevator is lowered. Is moved to a desired location.

JP 2003-226406 A

Generally, in order to perform cleaning, CVD, and many other surface treatments on a wafer as a semiconductor manufacturing substrate, a large number of FOUPs (for example, 24 sheets) that can be inserted and removed are used, and these FOUPs are It is transported along an in-process annular track or an inter-process annular track by transport means such as an OHT carriage.
Then, a desired surface treatment is performed at various surface treatment stations arranged on the FOUP transport path (in particular, the in-process annular track).

In addition to these various surface treatment stations, FOUPs containing wafers that have not undergone any surface treatment, or stockers for storing FOUPs that have partially or wholly completed the necessary surface treatments are arranged at predetermined locations. ing.
The stocker is large enough to have a relatively small to multi-stage FOUP storage shelf as shown in the above-mentioned Patent Document 1, and to provide maintenance and inspection doors inside the stocker every predetermined number of stages. Diversified to scale.
In particular, the FOUP stocker tends to increase in size with the recent increase in wafer size and the required number of wafers.

In this way, if the size of the FOUP stocker exceeds a certain limit, the robot that sends and receives the FOUP to the shelves in the stocker is obstructed from normal operation due to a power failure or other cause. The technique disclosed in Patent Document 1 cannot be adopted as a means for taking out the image.
That is, in a stocker of a scale that is provided with maintenance and inspection doors for every predetermined number of FOUP storage shelves in the height direction, when a robot malfunctions, the predetermined FOUP is taken out from the maintenance and inspection doors. Therefore, it is no longer possible to carry out emergency take-out using a stacker crane.

SUMMARY OF THE INVENTION An object of the present invention is a container (FOUP) stocker that is transported along a predetermined transport path and detachably accommodates wafers, and FOUPs are loaded from a loading port to a number of shelves for FOUP placement. This is a large stocker that has a multi-stage shelf and has a maintenance / inspection door for each predetermined number of stages in a configuration in which a robot for transferring to a carry-out port of a FOUP placed on the shelf is installed. Even when the transfer robot cannot normally operate, it is easy to take out the desired FOUP in the stocker in an emergency manner.

Means and effects for solving the problems

In order to solve the above-mentioned problem, a stocker according to claim 1 includes a plurality of shelves for storing articles conveyed by a carriage traveling along a predetermined conveyance path, an article carry-in port, an article carry-out port, A robot that handles transfer and transfer of articles between a shelf, an article carry-in port, and an article carry-out port. The door has a bellaland-like scaffolding on the outside of at least the second door from the lower side of the door, and includes a ladder that is erected in a vertical direction at a position that can be linked to each scaffolding.

According to the first aspect of the present invention, in the stocker having a plurality of article storage shelves and a robot responsible for placing the predetermined articles on the predetermined shelves or taking out the predetermined articles from the predetermined shelves, When the robot cannot operate normally due to various circumstances such as a power failure or reading failure of a tag attached to an article, and emergency takes time to repair the robot, emergency treatment can be performed.
More specifically, for example, when a robot that is being handled in the stocker becomes inoperable and an article placed on a predetermined shelf in the stocker needs to be taken out urgently, the predetermined shelf belongs. A person enters the stocker from the door, takes out a predetermined article, carries the article, gets off the ladder, and transports it to a predetermined place (such as an OHT carriage station) in the vicinity.

A stocker according to a second aspect is the stocker according to the first aspect, further comprising means for manually raising and lowering the article along the ladder.
According to the second aspect of the present invention, the effect of the invention according to the first aspect of the cited reference can be relaxed, in particular, the restriction on the weight of the article that occurs when a person holds the article and moves up and down the ladder.
The stocker according to claim 3 is the stocker according to claim 1 or 2, wherein the article is a container (FOUP) for detachably storing a wafer to be surface-treated. According to the invention according to No. 3, the effect of the invention according to Claim 1 or 2 cited above is originally placed on many shelves in the stocker, and subsequent surface treatment of the retained wafer is performed based on time management. The FOUP that needs to be transported by the robot in the stocker is manually taken out when the robot cannot be operated, and the necessary surface treatment is performed on the wafer without losing the necessary time. It can be done accurately without waiting for repair.

According to a fourth aspect of the present invention, in the stocker according to the first or second aspect, the means for manually raising and lowering the article is guided along the handrail arranged in parallel with the ladder. A carriage, an elevator plate supported by the carriage, on which an article is placed, a wire that fixes one end to the elevator board and moves the elevator board up and down, and winding and feeding the other end of the wire And a handle having a locking action for preventing the winding and unwinding.
According to the invention according to claim 4, the effect of the invention according to claim 2 or 3 to be cited is
When the handling robot in the stocker becomes inoperable, it is safe and reliable by manual operation along the handrail of the ladder provided on the outer wall of the stocker even if it is an article that cannot be lifted and lowered by weight and size. Can be moved up and down.

The stocker according to claim 5 is the stocker according to claim 4, wherein only when the lift plate is operated, a gap between the ladder and the handrail is set between the ladder and the handrail between the ladder and the handrail. It is provided with a connecting member that has a folding function to allow the handrail to approach the ladder when the lift plate is not in operation, and when the lift plate is in operation, the lower end of the handrail touches the basic surface for stockers via a stopper. It is characterized by touching.
According to the invention according to claim 5, the effect of the invention according to claim 4, which has been cited, is based on the vertical direction used for emergency only during an abnormal period when the robot operating in the stocker cannot operate normally. Since the interval between the installed ladder and its handrail can be eliminated when the robot is operating normally, the area around the stocker can be used effectively.

The stocker according to claim 6 is the stocker according to claim 2 or 3, wherein means for manually raising and lowering the article is arranged in parallel with the ladder, and forms a columnar linear guide member, and the linear guide member Supported by the lift plate, the lifting plate for placing the article, one end fixed to the lift plate, the wire for moving the lifting plate up and down, the winding and feeding of the other end of the wire, and the winding and feeding. It is characterized by comprising the handle which bears the lock action which prevents.
According to the invention according to claim 6, the effect of the invention according to claim 2 or 3 to be cited is
When the handling robot in the stocker becomes inoperable, manual operation is performed along the linear guide provided in parallel with the ladder provided on the outer wall of the stocker even if it is an article that cannot be lifted and lowered artificially in weight and size. Can be moved up and down.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
First, the outline of the drawings will be described. FIGS. 1 and 2 are a plan view and a front view of a stocker to which the present invention is applied, respectively, and FIG. 3 is a front view and a view showing a lifting mechanism of an article (FOUP) provided in the stocker. 4 is a partial side view of FIG. 3, FIG. 5 is a partial plan view of FIG. 3, FIG. 6 is a side view showing a main part in a folded state of the elevating mechanism, and FIG. FIG. 8 is a perspective view showing a lifting mechanism for an article (FOUP) according to another embodiment.

Now, the peripheral configuration of the stocker to which the inventions of the present application are applied will be specifically described with reference to FIGS. 1 and 2, reference numeral 1 denotes a stocker, which places a large number of shelves 2 and articles (FOUPs containing wafers subjected to various surface treatments) 3 on the shelves 2 or takes out the articles 3 from the shelves 2. The robot 4 is held inside.
Next, an external configuration including the configuration according to each invention of the present application in the stocker 1 will be described. 5 is a carry-in port for the article 3, and 6 is a carry-out port for the article 3, which are provided on the side surface of the stocker 1 along the traveling path 8 of the OHT carriage 7.

9 is a ladder, which is composed of a pair of upright columns 9a, 9b and a horizontal member 9c arranged at an appropriate interval between the opposing surfaces of the columns 9a, 9b. The columns 9a, 9b are It is supported and fixed to a predetermined outer wall of the stocker 1 via an angle member 10.
11 is a handrail for the ladder 9, and when the robot 4 cannot be operated, an article 3 lifting plate (details will be described later) 12 for emergency removal of the article 3 placed on a predetermined shelf 2 in the stocker 1 is provided. Also serves as a vertical guide. 12a is a protrusion that engages with a recess (not shown) formed at the bottom of the FOUP and regulates the placement position of the FOUP 3 on the lifting plate 12. Reference numeral 13 denotes a wire winding and feeding operation mechanism for manually operating the elevating plate 12, the details of which will be described later.

Reference numeral 14 denotes a maintenance / inspection door, which is provided for each predetermined number of shelves 2 in the stocker 1, and is automatically placed on the shelves 2 or taken out of the shelves 2 due to a robot failure or the like. Therefore, the necessary number corresponding to the number of shelves in the vertical direction is provided for people to enter and exit.
Reference numeral 15 denotes a veranda-shaped scaffold, which is provided corresponding to each maintenance / inspection door 14 and has a configuration in which a person entering and exiting the stocker 1 from the door 14 can stably perform the work. It is configured to allow people to enter and exit freely.
The veranda-like scaffolding 15 is not required to be provided at the lowest level if there is not much difference between the installation level of the stocker 1 and the lowest level of the door 14.

Next, the lifting mechanism of the article (FOUP) 3 will be described with reference to FIGS. 3 to 5 and FIG. In each figure, the columns 9a and 9b of the ladder 9 and the handrail 11 are rotatably supported at both ends at both ends, and are connected by connecting members 16 arranged at appropriate intervals. The interval between the pillars 9a and 9b of the ladder 9 and the handrail 11 can be adjusted by changing the inclination.
Reference numeral 17 denotes a carriage, and the substrate 17 a is fixed to both sides of the lifting plate 12. Two pairs of guide wheels 17b are rotatably fixed to the base plate 17a of the cart, and the handrail 11 is arranged so that each pair of guide wheels 17b sandwiches the handrail 11. As a result, the elevating plate 12 can move up and down along the handrail 11.
Since the guide wheel 17b meshes with the handrail 11 in the front-rear direction of FIG. 3, there is no fear of coming into contact with the connecting member 16 that is rotatably fixed between the side surfaces of the column 9a and the handrail 11. This does not prevent the guide wheel 17b from moving along the handrail 11.

Reference numeral 18 denotes a wire, which receives a winding / unwinding operation from the operation mechanism 13, and an outer end thereof is fixed to the elevating plate 12 via a pulley 19 supported at an appropriate position of the stocker by an appropriate means.
Reference numeral 20 denotes a stopper, which is provided at the lower end of the handrail 11. When an unillustrated article (FOUP) is placed on the elevating plate 12, and the elevating plate is in an operating state in which the elevating plate moves up and down, the lower end of the handrail 11 Supports the weight added to the.
In a situation where vibration occurs when the elevating plate 12 moves up and down, and stable elevating movement of the elevating plate 12 cannot be obtained, a separate fixing member that suppresses vibration of the stopper 20 is used as a known appropriate means. May be added.

  On the other hand, when the robot 4 in the stocker 1 is in a normal state (usually in most situations), the elevator plate 12 is moved to the top and the handrail 11 is moved upward as shown in FIG. As a result, the connecting member 16 rotates upward, and the handrails 11 corresponding to the columns 9a and 9b of the ladder 9 come close to the columns 9a and 9b.

Next, a specific mechanism example of the wire winding and feeding operation mechanism 13 will be described. In FIG. 7, reference numeral 13 a denotes a reel that winds and feeds the wire 18. A gear 13b is connected to the reel 13a so as to rotate integrally with the reel 13a.
A worm gear 13c meshes with the gear 13b and rotates with the rotation of the handle 13d.
At this time, the gear 13b and the worm gear 13c perform a reduction action at a reduction ratio corresponding to the difference in the number of teeth.
As a result, the rotational speed of the handle 13d is decelerated at a reduction ratio determined in accordance with the number of teeth of the gear 13b and the worm gear 13c, and the reel 13a has the reduction ratio compared to the force applied to the handle 13d. A large rotational force is obtained according to

Reference numeral 13e denotes a brake that applies an appropriate braking force to the worm gear 13c and prevents the handle 13d from rotating in the reverse direction. Thus, even if the handle operation is mistaken in the winding / unwinding operation of the wire 18, it is determined that the handle 13d does not reversely rotate in a natural state.
The brake 13e can be changed to an appropriate well-known means for locking the handle 13d when the handle 13d is not operated.

The operation of the configuration shown in FIGS. 1 to 7 will be described.
First, the robot 4 operating in the stocker 1 normally identifies the FOUP 3 and transfers the FOUP 3 placed in the FOUP carry-in port 5 to the predetermined shelf 2 or unloads the predetermined FOUP 3 from the predetermined shelf 2. Under the situation where the transfer to the port 6 is properly performed, there is no room for people to go in and out through the door 14 except for the regular maintenance and inspection of the stocker 1.
In such a case where the stocker 1 is operating normally, the elevating plate 12 has no room for operation, and the carriage 17 is raised to the top of the handrail 11 as shown in FIG. A means for this purpose is to manually operate the handle 13d of the wire winding / feeding operation mechanism 13 shown in FIG. 7, and to reduce the gear according to the meshing between the worm gear 13c and the gear 13b directly connected to the handle 13b. This is achieved by amplifying the torque and winding the wire 18 around the reel 13a.

At this time, the elevating plate 12 rises to the top of the handrail 11 along the handrail 11 of the carriage 17, and then raises the handrail 11 by an appropriate means (not shown) as shown in FIG. In accordance with the inclination of 16, it is fixed by appropriate means so that there is no space between the handrail 11 and the columns 9 a and 9 b of the ladder 9 (only the column 9 b appears in FIG. 6).
As a result, during normal operation of the stocker 1, the position of the handrail 11 can be brought close to the columns 9a and 9b of the ladder 9 to ensure a wide working area around the stocker 1.

Now, in the stocker 1, load handling operations such as transfer of the FOUP 3 placed in the FOUP carry-in port 5 to the predetermined shelf 2 or transfer of the predetermined FOUP 3 from the predetermined shelf 2 to the FOUP carry-out port 6 are performed. When the robot 4 cannot operate normally and the predetermined FOUP 3 cannot be automatically transferred to the FOUP carry-out port 6, basically, the operation of the robot is resumed.
However, the wafers stored in the FOUP 3 are sequentially subjected to the necessary surface treatment, so that it takes a long time to move to the station that receives the predetermined surface treatment. Significantly reduces the yield. Further, the surface treatment work efficiency of the FOUP 3 housed in the stocker 1 is also lowered, and consequently the overall surface treatment efficiency of the in-process annular track 8 including the stocker 1 including the FOUP 3 conveyed by the OHT carriage 7 is lowered. Come on.

In order to improve such an adverse effect, when the robot 4 is in a non-operating state, the emergency extraction target FOUP 3 in the stocker 1 is transferred to an external station by an operator.
The process during this time is as follows.
First step:
The relative positions of the columns 9a and 9b of the ladder 9 and the handrail 11 are changed from the approaching state shown in FIG. 6 to the horizontal state as shown in FIG. The plate 12 is movable in the vertical direction along the handrail 11.

Second step:
The height of the carriage 17 and the lifting plate 12 fixed to the carriage 17 is wound up to a height suitable for placing the FOUP 3 on the lifting plate 12 from the veranda-like scaffold 15 where the FOUP 3 that requires emergency removal is located. Then, the handle 13d of the feeding operation mechanism 13 is manually operated.
Third step:
The operator enters the stocker from the door 14 to which the FOUP 3 requiring emergency removal belongs, and carries the FOUP 3 to the corresponding veranda-like scaffold 15.

Fourth step:
In the veranda-like scaffolding 15, the FOUP 3 requiring urgent take-out is placed on the waiting lifting plate 12 in a stable state (a state in which it is engaged with a protrusion 12 a located on the upper plane of the lifting plate in a recess formed in the bottom of the FOUP. ).
Fifth process:
The handle 13d of the wire winding and feeding operation mechanism 13 is manually operated, and the FOUP 3 is lowered to the ground level that is the basis of the stocker 1.
Step 6:
An operator transports the FOUP 3 that requires emergency removal to a station that performs a desired surface treatment or a station that is close to the stocker 1 in the in-process annular track.

In addition, although the said 1st-6th process has disclosed the example which carries out the FOUP3 which needs emergency removal from the stocker 1 outside, the robot 2 is urgently put on the shelf 2 in the stocker 1 in the reverse process. The predetermined FOUP 3 can be manually stored in the predetermined shelf 2 without any operation.
By the way, the means for manually raising and lowering the article (FOUP etc.) 3 provided along the ladder in the above configuration is the scale of the article (FOUP etc.) 3 that can raise and lower the ladder 9 while a person is holding the article. If it is (size, weight, etc.), it is not enough to provide.
In this case, the steps 4 and 5 are not performed, and the process proceeds from the step 3 to the step 6.

FIG. 8 shows an example of a configuration that performs substantially the same operation as FIG. 3 described above.
Constituent elements equivalent to those in FIG. 3 are denoted by the same reference numerals, and description thereof is omitted. In FIG. 8, reference numeral 30 denotes a linear guide member, which has a columnar shape and is erected adjacent to one of the columns 9 a of the ladder 9. An engaging element (not shown) of the elevating plate 12 is guided by the recess 30a formed in the linear guide member 30, and the elevating plate 12 can be guided up and down while maintaining a horizontal state.

Reference numeral 28 denotes a wire, which is guided by the concave line 30a formed in the linear guide member 30 of the elevating plate 12, and its tip end is fixed to the engaging element of the elevating plate 12. A first pulley 29 is provided to change the direction of the wire 28, and is provided at an upper portion of the linear guide member 30 and the column 9a of the ladder 9 adjacent thereto by an appropriate means.
Reference numeral 13x denotes a second pulley that restricts the wire 28 that is fed or wound outward from the wire winding / feeding operation mechanism 13 in parallel with the longitudinal direction of the recess 30a of the linear guide member 30.

It is a top view of a stocker to which the present invention is applied. It is a front view of a stocker to which the present invention is applied. It is a front view which shows the raising / lowering mechanism of the articles | goods (FOUP) provided in the stocker. FIG. 4 is a partial side view of FIG. 3. FIG. 4 is a partial plan view of FIG. 3. It is a side view which shows the principal part of the folding state of an raising / lowering mechanism. It is a block diagram which shows the structure of the manual operation mechanism of an raising / lowering mechanism. It is a perspective view which shows the raising / lowering mechanism of the articles | goods (FOUP) which shows another Example.

Explanation of symbols

1 ... Stocker 2 ... Shelf 3 ... FOUP
4 ... Robot 5 ... FOUP carry-in port 6 ... FOUP carry-out port 7 ... · OHT cart 8 ··· OHT cart travel route 9 · · · Ladder 9a, 9b · · · ladder support 9c · · · · .. Ladder horizontal member 11... Handrail 12... Mounting table 13... Wire winding and feeding operation mechanism 14. ... door 15 ... veranda-like scaffold 16 ... connecting members 18, 28 ... wire 30 ... .... Linear guide member 17 ... Carriage

Claims (6)

A number of shelves for storing articles conveyed by a carriage traveling along a predetermined conveyance path, an article carry-in port, an article carry-out port, and exchange of articles among the shelves, the article carry-in port and the article carry-out port; In a stocker consisting of a robot responsible for transport and having a multi-stage configuration,
Each of the plurality of steps in the multi-stage structure has a maintenance inspection door and a veranda-like scaffold positioned at least outside the second or more doors from below, and stands vertically in a position that can be linked to each scaffold. Stocker with a ladder to be used.   The stocker according to claim 1, further comprising means for manually raising and lowering the article along the ladder. The stocker according to claim 1 or 2, wherein the article is a container for detachably storing a wafer subjected to a surface treatment. Means for raising and lowering the article manually includes a handrail arranged in parallel with the ladder, a carriage guided along the handrail, a lifting plate supported by the carriage and placing the article, It is composed of a wire that fixes one end to the elevating plate and moves the elevating plate up and down, and a handle that performs the winding and feeding of the other end of the wire and the locking action that prevents the winding and feeding. The stocker according to claim 2 or 3, characterized in that   Folding between the ladder and the handrail between the ladder and the handrail only when the lift plate is in operation, and between the ladder and the handrail. The stocker according to claim 4, further comprising a connecting member having a function, wherein a lower end portion of the handrail abuts against a stocker base surface via a stopper when the lifting plate is in operation. Means for manually raising and lowering the article is arranged in parallel with the ladder, and forms a columnar linear guide member, supported by the linear guide member, and a lifting plate for placing the article, and one end portion of the lifting plate. 3. A wire for fixing and moving the lifting plate up and down, and a handle for taking up and feeding out the other end of the wire and a locking action for preventing the winding and feeding out. 3. The stocker according to 3.

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