JPH05709A - Clean storage crane - Google Patents

Abstract

(57) [Summary] [Purpose] Correct the error in the amount of exit of a pair of exit arms. [Structure] A pair of swing-out arms 5 and 5 provided on a lift table 4 that moves up and down along a post 3 are formed by connecting a first arm 6, a second arm 7, and a third arm 8, respectively.
The cassette C is held by changing the angle between the connected arms to move the holding tool 9 horizontally, and moving the holding tool 9 toward and away from each other. By constructing the waist bending link 10 between the indirect portions of the second arm 7 and the third arm 8, displacement of the swing-out position between the two swing-out arms 5 and 5 is prevented and the obstacles for approaching and separating are prevented. To do.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crane for clean storage, which is insensitive to dust generation, and more particularly to the structure of a transfer device for the crane.

[0002]

2. Description of the Related Art In order to temporarily store a semi-processed product, such as a silicon wafer, in which dust must be prevented from adhering in a factory, a plurality of shelves and a crane are built in, and a clean storage device equipped with an air cleaning device is provided. The warehouse is being used. A crane with a special structure is applied to the clean storage crane to reduce dust from the drive unit, and one of them is a type that uses a swing-out arm as a transfer mechanism. The swing-out arm is composed of a group in which two or more arms are connected to each other and are synchronized and interlocked. Each set expands and contracts by changing the angle between the connected arms while keeping the corresponding arms in each set parallel to each other, and moves the cassette gripper at the tip of each set to the gripping position. The buckets are gripped and released by moving the respective sets closer to and away from each other.

[0003]

In the transfer device using a set of swing-out arms as described above, if both swing-out arms are not swung accurately in synchronization with each other.
A delivery error may occur, or the cassette may tilt and fall. For accurate synchronization, for example, the rod may be hung between the two swing-out arms, but it is impossible to move the rods closer to and away from each other. In addition, the spline telescopic rod and the like are adapted to approach and retreat, but at that time, they tend to twist.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a clean storage crane having a swing-out arm which can swing out accurately in synchronization with each other without disturbing the approach and separation of the swing-out arm.

[0005]

In order to achieve the above object, the present invention provides a set of swing-out arms, each of which is formed by connecting two or more arms, and the corresponding arms between the sets are parallel to each other. For a clean storage with a mechanism that changes the angle between the connected arms while maintaining the relationship, slides the gripping tool at the tip of each set in a substantially horizontal direction, and moves each gripping tool toward and away from each other to perform a transfer operation. In a crane, each end of a waist bending link having a waist bending portion that can be bent only in one direction is attached to a corresponding position between each pair of swinging arms so as to be rotatable only in a direction that does not prevent the waist bending link from being broken. A clean storage crane was constructed.

[0006]

Since the present invention has the above-mentioned structure, the following operational effects are obtained.

In the clean storage crane according to the present invention, when the swing-out arm is swung out and the gripping tool at the tip is slid in a substantially horizontal direction, the waist bending portion that can be folded in only one direction at a corresponding position between the sets. Since each end of the waist bending link having the above is attached so as to be rotatable only in a direction that does not prevent the waist bending link from being broken, the pair of swing-out arms are swung out in conjunction with each other, and the gripping tool moves in a substantially horizontal direction. It is possible to prevent a deviation from occurring sometimes. Further, when the set of swing-out arms is moved toward and away from each other, the waist bending link is bent in a substantially vertical direction to change its entire length.

Therefore, according to the clean storage crane of the present invention, since the two swing-out arms can be accurately synchronized and interlocked with each other, the gripping error or the article falls due to misalignment. I will not do it,
Moreover, it does not hinder gripping of the article.

[0009]

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

FIG. 1 is a front view showing an embodiment of a clean storage crane according to the present invention, and FIG. 2 is a side view showing a state in which the swing-out arms 5 and 5 of the same embodiment are swung out. is there.

In each drawing, a crane for a clean storage cabinet has a traveling carriage 1 traveling along a rail 2 and a traveling carriage 1
Is composed of a post 3 which is vertically provided upright, and an elevating table 4 which moves up and down along the post 3. On the upper part of the lifting table 4, a set of swing-out arms 5 and 5 is provided as a transfer device for transferring the cassette C to and from a shelf (not shown).
Is provided. Each of the swing-out arms 5 and 5 includes a first arm 6 and 6 (which does not rotate but is referred to as an arm for convenience), a second arm 7 which is rotatable with respect to the first arm 6 and 6, respectively.
7 and a cassette gripper 9, 9 at the tip, respectively,
It is formed by connecting third arms 8 and 8 which are rotatable to the arms 7 and 7, respectively, and swings out in the left-right direction in FIG. 2 and moves toward and away from each other. The first arm 6 does not rotate but only approaches and separates. With this configuration, a slit for approaching and separating is provided at a portion of the upper surface of the lifting table 4 where the first arm 6 projects. It is sufficient to provide only one, and a large opening for drawing out is not required. Therefore, it is difficult for dust and oil vapor generated from the drive mechanism built in the lifting table 4 to come out from the inside of the lifting table 4.

The connecting portions of the second arms 7 and 7 and the third arms 8 and 8 are connected by a waist bending link 10 which can be bent only in the vertical direction in FIG. The waist bending link 10 can be broken at the center, and the whole is bent in a semicircular shape.

FIG. 3 is a sectional view showing one structure of the swing-out arm 5, and FIGS. 4, 5 and 6 are views showing the inside of the first arm 6, the second arm 7 and the third arm 8, respectively.

In each figure, a sprocket 11 is pivotally supported near one end inside the first arm 6. The sprocket 11 is rotated by driving a chain 12 by a swing-out motor (described later) built in the lift 4. 13 is a tension adjuster for adjusting the tension of the chain 12, and 14 and 14 are tension sprockets for tensioning the chain.

The sprocket 11 is fixed to the second arm 7. By rotating the sprocket 11,
The second arm 7 rotates. A sprocket 15 having the same axis as the sprocket 11 is fixed to the second arm 7 near one end inside the second arm 7. Therefore, the sprocket 15 also rotates together with the sprocket 11.

A chain 16 is wound around the sprocket 15. 17 is a tension adjuster, 18 and 18
Is a tension sprocket. The chain 16 is wound around a sprocket 19 pivotally supported near the other end of the second arm 7, and is driven by the sprocket 15.
As shown in FIG. 5, the diameter size of the sprocket 19 is half the diameter size of the sprocket 15.

Since the sprocket 19 is fixed near one end of the third arm 8, the third arm 8 rotates as the sprocket 19 rotates. A sprocket 20 having the same axis as the sprocket 19 is fixed near one end inside the third arm 8. Therefore sprocket 20
Also rotates with the sprocket 19.

A chain 21 is wound around the sprocket 20. 22 is a tension adjuster. Further, a sprocket 23 pivotally supported near the other end inside the third arm 8 is wound around the chain 21. The diameter size of the sprocket 20 is half the diameter size of the sprocket 23.

The holder 9 is fixed to the sprocket 23 and rotates together with the sprocket 23. The holder 9 can always maintain a constant height even when the swing arm 5 is swung, and can maintain a horizontal posture. This is based on the ratio of the sprocket 15, 19 and sprocket 20, 23 diameter sizes.

As shown in FIG. 3, the waist bending link 10 is
Is the third along the extension of the sprocket 19, 20 axis.
A bracket 24 protruding from the arm 8 is rotatably attached. The connecting portion of the waist bending link 10 is shown in FIG. The two links are connected by a bearing 25,
Both sides of the bearing 25 are covered with caps 26, 26 to prevent dust generation and oil vapor generation.
As a result, the waist break link 10 can be bent only in the direction shown by the arrow in FIG. 3, and the mounting portion to the bracket 24 can be rotated in a direction that does not prevent the waist break link 10 from being broken. It has become.

The waist bending link 10 has a posture in which the center portion hangs downward when the swing-out arm 5 is folded, and a posture in which the waist bending link 10 is curved away from the cassette C as shown in FIG. Therefore, the cassette C held by the holder 9 does not hit.

8 to 11 are views showing the structure of a drive mechanism built in the lifting table 4, FIG. 8 is a partial sectional view taken along the axis of the spline shaft, FIG. 9 is a plan view, and FIG. 1
1 is a partial cross-sectional view taken along a plane perpendicular to the axis of the spline shaft, each showing only a part of the drive mechanism.

Both ends of the spline shaft 27 are pivotally supported by the side walls of the lift 4, and a plurality of grooves running in the axial direction are provided near both ends to form a spline shaft. In the meantime, it forms a cylindrical axis. A worm wheel 29 that is combined with the worm 28 is fixed to the cylindrical portion. Warm 2
Reference numeral 8 is fixed in the middle of a shaft 31 whose upper and lower ends are supported by the worm wheel cover 30. A pulley 32 is fixed near the upper end of the shaft 31. A timing belt 33 is wound around the pulley 32, and the timing belt 33 is wound around a pulley 35 fixed to a drive shaft of a descending motor 34.

Sprockets 36 are fitted near both ends of the spline shaft 27 so as to be slidable along the axial direction of the spline shaft 27. Chain 1 on sprocket 36
Since 2 is wound, the sprocket 11 shown in FIGS. 3 and 4 can be rotated by rotating the spline shaft 27. The sprocket 36 is axially supported by a sprocket case 37 to which the first arm 6 is fixed, and the sprocket case 37 is guided by a linear bearing 38 provided on the inner surface of the lift 4.
It can slide in a direction along the axis of the spline shaft 27.

The sprocket case 37 is attached to the round rack 39. A pinion 40 meshes with the round rack 39, and the pinion 40 is a chucking motor 41.
It is fixed to the drive shaft. A round rack 42 meshes with the pinion 40 on the opposite side of the round rack 39 sandwiching the pinion 40. Although not shown, the round rack 42 is a sprocket case 3 provided at the other end of the spline shaft 27.
It is attached to the same sprocket case as 7.
Therefore, the driving of the chucking motor 41 causes the round racks 39 and 42 to slide, which allows the swing-out arms 5 and 5 to move toward and away from each other.

In the present embodiment, the feeding motor 3
4. Since the above-described drive mechanism including the chucking motor 41 is arranged on one side of the lifting table 4 close to the post 3, the moment of inertia for lifting the lifting table 4 can be reduced and the rigidity of the post 3 can be reduced. Can be saved and the accuracy of the stop position can be improved.

Next, the operation of this embodiment will be described. As described above, the swing-out arms 5 and 5 are the swing-out motors 3
By actuating 4, the holder 9 is swung out so as to move in the horizontal direction while maintaining its posture, as shown in FIG. Next, the chucking motor 41 is actuated to move the swing-out arms 5 and 5 toward and away from each other, whereby the spacing between the holders 9 can be adjusted to hold and release the cassette C.

At this time, since the swing-out arms 5 and 5 are connected by the waist bending link 10, the positions of the indirect portions of the swing-out arms 5 and 5 of the second arm 7 and the third arm 8 correspond to each other accurately. It is possible to prevent the error of the swing angle of the swing-out arms 5 and 5 from being caused by being held at the position. Therefore, it is possible to prevent an accident such as a chucking error or the cassette tilting and dropping.

When the swing-out arms 5 and 5 approach each other and move away from each other, the waist bending link 10 is broken and the length thereof is changed, so that chucking is not hindered.

Further, since the waist bending link 10 is curved, it does not hit the cassette C as shown in FIGS.

In this embodiment, the holder 9 is provided with a limit switch 43 for detecting the cassette. Wiring to the limit switch 43 is provided inside the third arm 8 via the slip ring 44 (not shown), and further provided inside each arm via the slip ring for each indirect of each arm. It is connected to the inside of the lift 4. By utilizing these slip rings, it is possible to solve the problem that the wiring from the outside of the swing-out arm 5 is easily entangled in the related art.

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.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a clean storage crane according to the present invention.

FIG. 2 is a side view showing a state where the swing-out arm of the embodiment shown in FIG. 1 is swung out.

FIG. 3 is a cross-sectional view of the swing-out arm of the embodiment shown in FIG. 1 in a folded state.

FIG. 4 is an enlarged view showing a state in which a cover of the first arm of the swing-out arm of the embodiment shown in FIG. 1 is removed.

5 is an enlarged view showing a state in which a cover of the second arm of the swing-out arm of the embodiment shown in FIG. 1 is removed.

FIG. 6 is an enlarged view showing a state in which a cover of a third arm of the swing-out arm of the embodiment shown in FIG. 1 is removed.

FIG. 7 is an enlarged plan view showing a central connecting portion of the waist bending link of the embodiment shown in FIG.

FIG. 8 is a partially enlarged cross-sectional view showing a drive mechanism inside the lift table of the embodiment shown in FIG.

FIG. 9 is an enlarged partial plan view showing a drive mechanism inside the lift table of the embodiment shown in FIG.

10 is a partially enlarged cross-sectional view of the worm wheel cover taken along a plane perpendicular to the axis of the spline shaft inside the lift table of the embodiment shown in FIG.

FIG. 11 is an enlarged cross-sectional view of the round bar portion of the spline shaft taken along a plane perpendicular to the axis of the spline shaft inside the lifting table of the embodiment shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Traveling vehicle 3 Post 4 Lifting table 5, 5 Swing-out arm 6 1st arm 7 2nd arm 8 3rd arm 9 Holding tool 10 Hip break link C cassette

Claims (1)

Claim: What is claimed is: 1. A set of swing-out arms, each of which is formed by connecting two or more arms, is connected between arms in which corresponding arms in each set are connected while maintaining a mutually parallel relationship. In a clean storage crane equipped with a mechanism for performing a hand-over operation by sliding the grips at the tip of each set in a substantially horizontal direction by changing the angle of each set, each set of each swing arm A clean storage cabinet characterized in that each end of a waist bending link having a waist bending portion that can be bent only in one direction is attached to a corresponding position between the spaces so as to be rotatable only in a direction that does not prevent the waist bending link from being broken. Crane.