JP2002295414A - Moving mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a moving mechanism capable of moving a prescribed member to a prescribed position. SOLUTION: The moving mechanism is provided with a rodless cylinder 6. The rodless cylinder 6 is provided with a cylinder tube 7, a piston 21, and a mover 8. The piston 21 is provided with annular magnets 25, 26, and 27 and the mover 8 is provided with the annular magnets 30, 31, and 32. The annular magnets 25, 26, 27, 30, 31, and 32 are regularly disposed at an alignment pitch L along the moving direction of the piston 21. Through attraction between the magnetic poles of the annular magnet poles 25, 26, and 27 and the corresponding magnetic poles of the annular magnets 30, 31, and 32, the piston 21 and the mover 8 are intercoupled in a magnetic manner. A regulating member 34 is situated below the side of the cylinder tube 7. An upper end D of a regulation member 34 is situated between a moving lower end B of the mover 8 and a position below by a distance L/2 extending from the moving lower end B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to a mechanism for moving a predetermined member to a predetermined position, for example, a moving mechanism used for opening and closing a lid of a container for accommodating a semiconductor wafer or the like.

[0002]

2. Description of the Related Art Some substrate processing apparatuses for processing a substrate such as a semiconductor wafer can set a wafer container called a pod. The wafer container is a closed hermetically closed container capable of housing a cassette for stacking and holding wafers in multiple stages, and has an opening formed in a direction of taking out the wafer from the cassette, and a removable lid is provided in this opening. I have. Therefore, if the lid is closed and the internal space of the wafer container is kept clean, the wafer can be transported and stored while keeping it in a clean state.

The substrate processing apparatus is provided with a lid opening and closing mechanism for automatically opening and closing the lid of the wafer container. The lid opening / closing mechanism includes a link that can be coupled to the lid, and a moving mechanism for moving the link to detach the lid from the wafer container and retracting the lid from the front of the opening of the wafer container. I have. Although this moving mechanism has a driving mechanism such as an air cylinder, a rodless cylinder is used when it is difficult to secure a space due to design limitations of the apparatus.

The rodless cylinder includes a tubular cylinder tube, a piston provided inside the cylinder tube and moved by the action of air pressure, and a movable member provided around the cylinder tube and connected to the piston by magnetic force and moved. ing. The piston and mover are
Each has a magnet, and the piston and the mover are connected by magnetic force. The magnet provided on the piston is configured such that both the north pole and the south pole appear on the mover side. Similarly, the magnet provided on the mover is S
The pole and the N pole are both configured to appear on the piston side. The mover is connected to the piston inside the cylinder tube by the attractive force that acts between the N and S poles of the magnet provided on the piston and the S and N poles of the magnet provided on the mover. .

[0005] A member to be moved, for example, a lid of a container is mechanically connected to the mover. When the piston moves due to the air pressure, the mover moves accordingly, and the member connected to the mover moves. The piston and the mover move while maintaining the relative positional relationship substantially constant. In order to strengthen the magnetic coupling between the piston and the moving element, each of the piston and the moving element includes a plurality of magnets. That is, the piston and the mover are connected by an attractive force between a plurality of pairs of N poles and S poles. The plurality of magnets having the same shape and size are arranged at predetermined intervals such that N poles and S poles alternately appear along the moving direction of the piston. Therefore, the magnetism of these magnets has a pattern that repeats at a fixed unit length.

[0006]

However, since the cylinder and the moving element are connected only by magnetic force and are not mechanically connected, when an excessive load is applied to the moving element, the cylinder and the moving element correspond to the magnetic poles of the piston. The magnetic pole of the moving element sometimes shifts. That is, in a state where the unit of the magnetic pattern is shifted by one (or more), the piston and the mover may be connected.

In particular, when the rodless cylinder is disposed vertically and a vertical force acts on the movable element, if the movement is stopped after moving the movable element downward, the member connected to the movable element may be moved. In addition to the working gravity, the inertial force of the moving member acts in the same direction (downward). Therefore, a large force acts to temporarily shift the connection between the piston and the mover. If the magnetic pole of the piston deviates from the corresponding magnetic pole of the mover, the member connected to the mover is displaced by one (or more) of the magnetic pattern and is no longer predetermined. You cannot move to the position. Further, in such a state, the effective magnetic poles of the magnetic poles of the piston and the moving element are reduced, so that the magnetic coupling between the piston and the moving element is weakened. Therefore, there is a possibility that the magnetic poles of the piston and the corresponding magnetic poles of the moving element are further shifted.

An object of the present invention is to provide a moving mechanism capable of moving a predetermined member to a predetermined position.

[0009]

Means for Solving the Problems and Effects of the Invention According to the first aspect of the present invention, there is provided a tubular cylinder tube (7), which is provided inside the cylinder tube by the action of air pressure. Moving piston (2
1) and a moving mechanism for moving a predetermined member using a rodless cylinder (6) having a mover (8) provided around the cylinder tube and connected to the piston by magnetic force to move. A restricting member for restricting the movement of the mover in the vicinity of an end of a predetermined movement range of the mover so that the piston of the rodless cylinder and the mover are not disconnected from each other in a predetermined state. A moving mechanism comprising (34, 35).

[0010] Alphanumeric characters in parentheses indicate corresponding components in the embodiment described later. Hereinafter, the same applies in this section. The moving element is often rapidly decelerated near the end of the predetermined moving range. Therefore, in such a position, an excessive load is often applied to the movable element. According to the present invention, since the regulating member is provided near the end of the predetermined moving range, the movement of the moving element is mechanically restricted by the restricting member, and the piston and the moving element are magnetically coupled in a predetermined state. Does not come off. Therefore, the moving mechanism having such a rodless cylinder can move a predetermined member to a predetermined position.

The regulating member may be a projection provided on the outer surface of the cylinder tube. The restricting members may be near both ends of a predetermined moving range of the moving element. When a large force acts on the movable element only at one end of the moving range, the regulating member may be provided only near one end of the moving range. The piston is provided with a plurality of magnets (25, 26, 27), and the mover is provided with a plurality of magnets (30, 31, 3, 3).
2), wherein the magnetic coupling is such that the magnetism provided by the plurality of magnets provided on the piston and the magnetism provided by the plurality of magnets provided on the mover act in a predetermined correspondence relationship. Is also good. Multiple sets of N with multiple magnets
Due to the attractive forces of the poles and the south poles, a strong magnetic coupling between the piston and the mover is obtained.

According to a third aspect of the present invention, the restricting position of the restricting member is such that a repetitive unit length (2 × L) of the magnetic pattern by the plurality of magnets with respect to an end of a predetermined moving range of the moving element. 3. The moving mechanism according to claim 2, wherein the moving mechanism is located between a position outside by half the length of the magnetic pattern and a position inside by half the repeating unit length of the magnetic pattern by the plurality of magnets. 4. . According to the present invention, even when an excessive load is temporarily applied to the movable element and the relative positional relationship between the movable element and the piston is shifted, the offset can be suppressed to less than half of the repetitive unit length of the magnetic pattern. . Therefore, the repetition unit of the magnetic pattern does not shift by one, and after the excess load is removed, the piston and the mover are restored to the original relative positional relationship by the magnetic force,
It is possible to maintain a predetermined magnetically connected state.

According to a fourth aspect of the present invention, the position regulated by the regulating member is defined by an arrangement pitch (L) of a plurality of magnets that generate the magnetic coupling with respect to an end of a predetermined moving range of the movable element. 3. The moving mechanism according to claim 2, wherein the moving mechanism is located between a position outside by a half length and a position inside by a half length of an arrangement pitch of the plurality of magnets causing the magnetic coupling. . According to the present invention, even if an excessive load is temporarily applied to the movable element and the relative positional relationship between the movable element and the piston is shifted, the shift can be suppressed to less than half the arrangement pitch of the magnets. Therefore, since the predetermined magnetic coupling is still working effectively, there is no deviation due to the magnet arrangement pitch, and after the excess load is removed, the piston and the mover move relative to each other by the magnetic force. The positional relationship can be restored, and the predetermined state of magnetic coupling can be maintained.

[0014]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is an illustrative side view showing a partial configuration of a substrate processing apparatus employing a moving mechanism according to an embodiment of the present invention. Pedestal 1
A wafer container 2 is installed on the top. Inside the wafer container 2, a cassette 3 that can store a plurality of semiconductor wafers can be stored. Wafer container 2
Is provided with a detachable lid 4 on the front surface. The lid 4
The link 5 is configured to be connectable to a rodless cylinder 6 disposed below the wafer container 2.
It is connected to. The rodless cylinder 6 includes a cylindrical cylinder tube 7 arranged in a vertical direction, and a movable member 8 provided around the cylinder tube 7, and can move the movable member 8 up and down. . The cylinder tube 7 is fixed at its upper and lower ends to a vertical support plate 9 via attachments 12.

The moving element 8 is connected to the link 5 via two connecting members 10 and 11 arranged vertically.
The upper connecting member 10 connects the movable member 8 and the link 5 at a constant interval. A cylinder 13 is interposed between the lower connecting member 11 and the mover 8, and the cylinder 13
Can change the distance of the link 5 with respect to the movable member 8. The link 5 and the mover 8 are moved by the cylinder 13.
Is changed, the link 5 rotates around the joint A between the connecting member 10 and the link 5 as a fulcrum. Thereby, the lid 4 is attached to and detached from the wafer container 2.

When the lid 4 is separated from the wafer container 2, the lid 4 can be moved up and down by moving the moving element 8 up and down. When the moving member 8 is near the lower end of the cylinder tube 7, the lid 4 is completely retracted from the front surface of the wafer container 2 when viewed from the front. In this state, the wafers in the cassette 3 can be taken in and out. FIG. 2 is an illustrative sectional view showing the structure of the rodless cylinder 6 shown in FIG.

The cylinder tube 7 has a hollow cylinder portion 15 and a head portion 16 arranged to close the upper and lower ends of the cylinder portion 15. The tubular cushion ring 1 extends from the head 16 toward the inside of the cylinder 15.
9 are overhanging. The tip of the cushion ring 19 is open. An air introduction / exit opening 17 is provided on the side of the head portion 16. The head section 16 is provided with an air vent 18 along the central axis of the cylinder tube 7. The air vent 18 is provided with the air inlet / outlet opening 17.
And, it communicates with the space inside the cushion ring 19, and does not communicate with the outside of the head portion 16 in other portions. That is, the space inside the cylinder portion 15 communicates with the outside only through the air introduction / exit opening 17. On the end face of the head portion 16 on the side of the cylinder portion 15, a concave portion 20 recessed in two steps is formed.

A piston 21 is provided inside the cylinder 15.
Are movably disposed close to the inner wall of the cylinder portion 15. The piston 21 has a head 1 at its upper and lower ends.
It has a convex part 22 projecting in two steps having a shape complementary to the concave part 20 of the six end faces. A guide hole 23 having a shape substantially complementary to the cushion ring 19 is provided along the central axis of the piston 21. A shaft 24 is provided at the center of the piston 21 along the central axis, and around the shaft 24, three ring-shaped magnets 25, 26, and 27 are arranged vertically. Between each of the ring magnets 25, 26, 27, the uppermost ring magnet 25
Above, and below the lowermost ring-shaped magnet 27,
A yoke 28 made of a material having a high magnetic permeability is arranged in close contact with the ring-shaped magnets 25, 26, 27.

Each of the ring magnets 25, 26, 27 has the same thickness, and each of the yokes 28 has the same thickness. The ring-shaped magnets 25, 26, 27
Magnetic poles appear in the vertical direction, and adjacent magnetic poles are arranged so as to face the same poles. In other words, the lower portion of the uppermost ring-shaped magnet 25 and the upper portion of the central portion of the ring-shaped magnet 26 are both opposed S poles S1P and S2P, and are opposed to each other. And the upper part of the ring-shaped magnet 27 are N poles N2P and N3P.

An annular movable member 8 is provided outside the cylinder portion 15.
Are movably fitted outside. The mover 8 has the side plate 2 on the outside.
9 and connecting members 10 and 11 (FIG. 1)
reference. ) Is fixed. Inside the side plate 29, three ring-shaped magnets 30, 31, and 32 are arranged in the vertical direction so as to correspond to the ring-shaped magnets 25, 26, and 27, respectively. A yoke 33 made of a material having high magnetic permeability is provided between the ring-shaped magnets 30, 31, 32, above the uppermost ring-shaped magnet 30, and below the lowermost ring-shaped magnet 32. It is arranged close to 30, 31, 32.

Similarly to the ring magnets 25, 26, and 27, the ring magnets 30, 31, and 32 also have magnetic poles in the vertical direction, and adjacent magnets are arranged so that the same poles face each other. However, the polarities of the ring-shaped magnets 30, 31, 32 are opposite to those of the corresponding ring-shaped magnets 25, 26, 27. Each of the ring-shaped magnets 30, 31, 32 has the same thickness, and the thickness is
5, 26, 27, respectively. Each of the yokes 33 has the same thickness.
8 equal to each thickness. That is, the ring-shaped magnet 2
5, 26, 27 and ring-shaped magnets 30, 31, 32
Has a regular repeating arrangement, and its pitch L
Is the thickness of one ring-shaped magnet 25 and one yoke 28
Equal to the sum of the thickness. Further, the ring-shaped magnets 25, 2
Since the magnetic poles 6, 27 and the ring-shaped magnets 30, 31, 32 are alternately arranged with their magnetic poles reversed, the repeating unit length of the magnetic pattern thereby becomes 2 × L.

The ring-shaped magnet 25 of the piston 21 and the ring-shaped magnet 30 of the mover 8 are such that the N magnet N1P and the S pole S1M exert an attractive force, and the S pole S1P and the N pole N1M exert an attractive force. Connected. Similarly, the ring-shaped magnet 26
And the ring-shaped magnet 31 are magnetically connected, and the ring-shaped magnet 27 and the ring-shaped magnet 32 are magnetically connected. As a result, if an excessive load is not applied to the moving element 8, the ring-shaped magnets 30, 31, and 32 are maintained at substantially the same vertical position as the ring-shaped magnets 25, 26, and 27, respectively.

The side of the lower head part 16 is
At a position close to 5, a ring-shaped regulating member 34 is provided. At the time of use, a compressed air pipe is connected to the air inlet / outlet opening 17. When compressed air is introduced from one air introduction / exit opening 17 and air leaks from the other air introduction / exit opening 17, the piston 21 moves up and down by the action of air pressure. Following this, the mover 8 moves while maintaining a predetermined relative positional relationship with the piston 21.

FIG. 3 is an illustrative sectional view showing the structure near the regulating member 34 of the rodless cylinder 6 of FIG. When the piston 21 moves to the lowermost end of the movable range, the convex portion 22 of the piston 21 is completely fitted and abuts on the concave portion 20 of the head portion 16. That is, the piston 21 cannot move further downward. At this time, mover 8
If an excessive load is not applied to the moving member 8, the lower end position of the moving member 8 is the moving lower end B. Upper end position D of regulating member 34
Is arranged between the lower end B of movement and the position below the lower end B of movement by half the pitch L.

When an excessive load is temporarily applied to the movable member 8 at this position, the movable member 8 moves downward against the magnetic coupling, and as shown in FIG. 34
Is brought into contact with. For example, when the piston 21 moves downward from above and stops suddenly at the lower end of the moving range, a large inertia force is temporarily applied to the moving element 8 in addition to the gravity acting on the lid 4 and the link 5. This is the situation. In such a state, the ring-shaped magnets 25, 2
The displacement of the ring-shaped magnets 30, 31, 32 with respect to the ring-shaped magnets 25, 26, 27, 30, 31, 31, 32
Is less than half of the pitch L. At this time, the piston 21
N poles N1P, N2P, N3P and S poles S1P, S2
P, S3P are still the corresponding south poles S1M,
S2M, S3M and the north poles N1M, N2M, N3M exert attractive forces. Therefore, when the excess load is removed, the moving element 8 moves upward by these magnetic forces, and the relative positional relationship with the piston 21 is restored to the original position. That is, the piston 21 and the moving element 8 can maintain the magnetic connection in a predetermined state. Therefore, the moving mechanism including such a rodless cylinder 6 can move a predetermined member (for example, the lid 4) to a predetermined position.

The upper end of the regulating member 34 may be arranged between the lower end B of movement and a position above the lower end B of movement by half the pitch L. Even in that case, the ring-shaped magnets 30, 31, and
32 is suppressed to less than half of the pitch L, and the piston 21 and the moving element 8 can maintain the magnetic coupling in a predetermined state. However, in this case, since the lower end of the moving element 8 contacts the regulating member 34 before reaching the lower end B, the impact at the time of contact is relatively large. For this reason, it is preferable that the regulating member 34 is disposed below the lower end B of movement.

FIG. 4 is an illustrative cross-sectional view showing a configuration near a regulating member of a rodless cylinder according to a modification of the rodless cylinder 6 of the embodiment shown in FIG. Portions having the same configuration as the rodless cylinder of the embodiment shown in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted. In this rodless cylinder, the upper end position D ′ of the regulating member 35 is disposed so as to be between a position lower by half the pitch L from the lower end B of movement and a position lower by a pitch L from the lower end B of movement. I have.

In this case, when an excessive load is temporarily applied to the movable member 8, the movable member 8 moves downward against the magnetic coupling, and its lower end is restricted as shown in FIG. 35. In such a state, the ring-shaped magnet 3 with respect to the ring-shaped magnets 25, 26, 27
The deviation of 0, 31, 32 is not less than half of the pitch L, but not more than half of the repeating unit length 2 × L of the magnetic pattern. Therefore, the magnetic force acts to maintain the original magnetic connection, so that the repeating unit of the magnetic pattern does not shift by one (or more).

In the above embodiment, the regulating members 34, 35
Is provided only near the lower end of the moving range of the moving element 8, but may be provided only near the upper end of the moving range, or may be provided both near the upper end and near the lower end of the moving range. When a large force is applied to the moving element 8 even above the moving range, such a configuration can prevent the magnetic coupling between the piston 21 and the moving element 8 from being shifted. In the above embodiment, the piston 2
Although the number of the ring magnets of 1 and the moving element 8 has been described as three each, the present invention is not limited to this. Further, the shape of the magnet need not be a ring shape.

In the above embodiment, the moving mechanism used for opening and closing the lid of the container accommodating the semiconductor wafer in the substrate processing apparatus has been described as an example. However, the present invention is not limited to this. The present invention can be applied to a moving mechanism for moving to a predetermined position. For example, the present invention can be applied to a moving mechanism for holding a predetermined article such as a substrate and moving the article in a horizontal direction or a vertical direction. In addition, various design changes can be made within the scope of the matters described in the claims.

[Brief description of the drawings]

FIG. 1 is an illustrative side view showing a partial configuration of a substrate processing apparatus employing a moving mechanism according to an embodiment of the present invention.

FIG. 2 is an illustrative sectional view showing the structure of the rodless cylinder shown in FIG.

FIG. 3 is an illustrative sectional view showing a configuration near a regulating member of the rodless cylinder in FIG. 2;

FIG. 4 is an illustrative sectional view showing a configuration near a regulating member of a rodless cylinder according to a modification of the rodless cylinder of the embodiment shown in FIG. 3;

[Explanation of symbols]

 Reference Signs List 6 rodless cylinder 7 cylinder tube 8 mover 21 piston 25, 26, 27, 30, 31, 32 ring-shaped magnet 34, 35 regulating member

Continued on the front page F term (reference) 3F022 AA07 AA08 BB09 CC02 EE05 HH01 3H081 AA03 BB03 DD02 DD12 EE27 FF03 HH04

Claims (4)

[Claims] 1. A tubular cylinder tube, a piston provided inside the cylinder tube and moved by the action of air pressure, and a movable member provided around the cylinder tube and connected to and moved by the piston by magnetic force. A moving mechanism for moving a predetermined member by using a rodless cylinder having a moving member, wherein a predetermined state of the moving element is controlled so that a magnetic connection between the piston of the rodless cylinder and the moving element in a predetermined state is not released. A movement mechanism comprising a regulating member for regulating the movement of the mover in the vicinity of an end of the movement range. 2. The piston includes a plurality of magnets, the mover includes a plurality of magnets, and the magnetic coupling includes the magnetism of the plurality of magnets provided on the piston and the mover. 2. The moving mechanism according to claim 1, wherein the magnetism provided by said plurality of magnets is obtained by acting in a predetermined correspondence. 3. A position restricted by the restricting member is a position outside of an end of a predetermined moving range of the movable element by a half of a repetition unit length of a magnetic pattern by the plurality of magnets; 3. The moving mechanism according to claim 2, wherein the moving mechanism is located between the inner side position and the inner side position by half a repetition unit length of the magnetic pattern by the plurality of magnets. 4. The position restricted by the restricting member is a position outside the end of the predetermined moving range of the movable element by a half length of an arrangement pitch of the plurality of magnets for generating the magnetic coupling. 3. The moving mechanism according to claim 2, wherein the moving mechanism is located between a position inside and a half of an arrangement pitch of the plurality of magnets that generate the magnetic coupling.