JPH0632499A - Noncontact holding device - Google Patents

Abstract

PURPOSE:To prevent turbulence of the ambiance in a clean room by providing a gas collecting port at the position surrounding near a gas chamber to form the balance of the positive pressure and the negative pressure operating depending on the Bernoulli's effect, and collecting the exhaust gas positively, and to provide a plate form noncontact holding device having a posistioning stopper which can be pulled out and pushed in so as to be inserted in a narrow space. CONSTITUTION:A gas ejection nozzle 31 whose diameter is expanded toward the opening, an extending wall connected to the peripheral edge of the opening of the gas ejection nozzle 31, and an exhaust gas collecting port 22a provided on the line surrounding the ejection nozzle 31 at each extending wall or at one group of extending walls, are provided. A movable pin stopper device driven to the position projecting to the outer side of the extending wall surface, or buried in a plate from member 2, is provided at a necessary position of the extending wall.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for holding a plate-shaped material, a sheet-shaped material, etc. in a non-contact state, and is particularly intended for loading or unloading into a narrow space.

[0002]

2. Description of the Related Art As a conventional technique of this type, the present invention is based on the Bernoulli effect disclosed in the specification attached to the Japanese Patent Application No. 4-40194 filed on Jan. 29, 1992. There is a contactless holding device. A chamber member having a cup-shaped recess and an extension wall extending from a peripheral edge of the circular opening of the recess along a plane of the opening, and a plate-shaped holding object positioned facing the opening of the chamber member. An object to be held by a gas chamber surrounded by a chamber member and a gas outlet for ejecting a gas from the center of the bottom of the chamber member to the gas chamber, and a balance between a positive pressure and a negative pressure generated in the gas chamber. Is a holding device which holds the chamber member in a non-contact manner with respect to the chamber member.

[0003]

In the above-mentioned non-contact holding device, the gas blown out from the opening of the chamber member leaks to the outside at a high speed from the gap between the chamber member and the holding object. Generally, a process of processing a substrate such as a semiconductor device or a liquid crystal is performed in a clean room. High-speed gas movement in a clean room disturbs the surrounding atmosphere, winds up dust and pollutes the air in the room, adversely affecting processing.

On the other hand, when the object is held by the holding device, the object has no physical contact with the gas ejected from the holding device other than the atmosphere, so that the holding force with respect to the position parallel to the extension wall is It is close to 0 and slips easily with a slight inclination and external force. For this reason, this kind of holding device is usually provided with a stopper for preventing lateral movement along the holding surface of the object. However, in the case of handling that can secure a sufficient movement space in the vertical direction, there are few problems, but in the case of a handling cassette rack that is used for handling a vertical movement space such as a silicon wafer or a liquid crystal glass substrate, Since the intervals at which the objects are arranged are extremely narrow, it is not possible to secure a space for inserting the holding device main body and the stopper thereof above the objects. Therefore, it has been impossible to load or unload them one by one.

The present invention is intended to improve the above-mentioned defect of the non-contact holding device. The first one is a gas chamber in which a positive pressure and a negative pressure are balanced in the non-contact holding device based on the Bernoulli effect. By arranging a gas recovery port at a position surrounding the vicinity of the room and actively collecting the exhaust gas, it is possible to reduce the leakage of the gas to the outside and prevent the disturbance of the atmosphere in the clean room.

Secondly, the holding device main body is formed into a thin plate shape so that it can be inserted into a narrow space in which an object is placed, and when the main body is inserted into the object placement space, the positioning is performed. An object of the present invention is to provide a contactless holding device configured so that the stopper does not hinder the insertion.

[0007]

The first gist of the present invention is as follows.
A gas ejection port whose diameter is enlarged toward one or a plurality of openings, an extension wall connected to a peripheral edge of the opening of the gas ejection port, and an air supply port to be connected to the gas ejection port and an air supply source. And a gas distribution chamber communicating with each other, and by ejecting a gas from the gas ejection port, a space in which a negative pressure and a positive pressure are balanced is formed between the object to be held and the extension wall to hold the object to be held. A holding device for holding the exhaust gas in a non-contact manner, the exhaust gas collecting port being arranged on a line that surrounds the ejection port of each of the extension walls, and an exhaust gas recovery circuit that connects the exhaust gas recovery port and the exhaust gas recovery port. It is in a non-contact holding device characterized by being provided.

The exhaust gas recovery port is a continuous or intermittent concave groove formed along a line surrounding the ejection port, and the exhaust gas recovery circuit is connected to an opening provided at an arbitrary position at the bottom of the concave groove. It can be a conduit to the air port.

In the gas distribution chamber and the exhaust recovery circuit, a loop-shaped groove is formed by connecting a required port to a plate-shaped member which is integral with or supports the extension wall and the gas ejection port, and the groove is covered. And a thin plate member.

Further, a second aspect of the present invention includes a gas ejection port whose diameter is enlarged toward the opening and an extension wall which is continuous with the peripheral edge of the opening of the gas ejection port. Is a holding device for holding the object to be held in a non-contact manner by forming a space in which the negative pressure and the positive pressure are balanced between the object to be held and the extension wall by ejecting A movable pin stopper device including a pin that can project outside the extended wall surface and a driving mechanism that drives the pin from a position where the pin is embedded in the plate-shaped member to a range that can project outside the extended wall surface. There is a non-contact holding device.

The movable pin stopper device has a rotary shaft penetrating along the extension wall of the plate member, a pin radially implanted at an arbitrary position of the rotary shaft, and one end of the rotary shaft. The drive mechanism is configured to repeatedly rotate the provided pin at a rotation angle within a range in which it can project from the position where the pin is embedded in the plate-shaped member to the outside of the extended wall surface.

Further, the movable pin stopper device is composed of a plunger type air cylinder connected to at least one externally controllable common port arranged at an arbitrary position on the extension wall surface in a direction perpendicular to the extension wall surface. You can also
In this case, the air cylinder has such an extent that the total length of the air cylinder is buried in the plate-like body when the total length is reduced, and the working end thereof is projected from the extension wall surface when extended.

[0013]

When the silicon wafer mounted on the rack of the cassette is to be loaded on the wafer processing machine by the holding device configured as described above, first the main holding device is positioned directly above the wafer of the cassette, Air supply and exhaust are performed from the air supply port and the exhaust port. By injecting the gas from the gas ejection port by the air supply, a space in which the negative pressure and the positive pressure are balanced is formed between the wafer and the extension wall, and the wafer is held without contact. . The ejected gas flows between the wafer and the extension wall and goes to the outside, but since the exhaust gas recovery port is arranged so as to surround each gas ejection port on the extension wall, the large amount of gas is discharged before it leaks to the outside. A part is collected. Next, the movable pin stopper device is actuated to prevent the wafer from moving laterally, and the wafer is pulled out from the cassette, moved to a predetermined position, and air supply / exhaust is stopped to release the holding state. After that, the movable pin stopper device is operated, the pin is housed in the holding device, and the above-described work is waited again.

The details of the embodiment will be described below with reference to the drawings.

[0015]

Embodiment 1 FIGS. 1 to 11 show a first embodiment of the present invention. The holding device 1 includes a plate-shaped body 2, an extension wall 3 that is a lower surface of the plate-shaped body 2 and faces a holding object (shown in phantom in FIGS. 1 and 2) 7, and one end of the plate-shaped body 2. 4, which is connected to a robot or other moving device, and an air supply port 50 and an exhaust gas which are provided on the joint 4 and connect the holding device to an air supply source or an exhaust source (neither is shown). The port 51 is a main constituent unit. The plate-shaped body 2 is composed of a substantially rectangular plate-shaped support member 20 and a thin plate member 30 having the same peripheral shape as the support member 20 attached to the plate-shaped support member 20 by a well-known coupling means. The extension wall 3 is formed.

As shown in the sectional views of FIGS. 4 and 6 or in FIG. 5, reference numeral 21 denotes a gas distribution chamber formed of a groove cut from the lower surface of the support member 20, and the joint 4 is provided from substantially the center of the support member 20. Is formed in the range up to. Reference numeral 22 is a concave groove (see FIGS. 4, 5 and 9) cut from the lower surface so as to surround the gas distribution chamber 21 and controls the exhaust recovery path. Four
0 is a joint fixing member, 41 is a joint supporting member, and the joint 4 is constituted by fixing the plate-like body 2 to the joint supporting member 41 with the fixing bolts 42. Further, the joint-side end portion 21b of the gas distribution chamber 21 communicates with the air supply port 50 fixedly provided in the joint fixing member 41, and the end portion 22a of the gas recovery chamber 22 of the exhaust recovery passage 22 on the support member side is connected. , The gas distribution chamber 21
Forming an arc with a large radius r centered on the end 21a of
The other end 22b of the exhaust gas recovery passage 22 has a joint fixing member 41.
To the exhaust port 51 fixed to

On the other hand, the thin plate member 30 adhered to the supporting member 20 by means of a countersunk screw 23 or other suitable connecting means,
As is apparent from the bottom view of FIG. 5 and the cross-sectional view of FIG. 6, a conical gas ejection port 31 whose diameter is enlarged toward the lower surface is formed at a portion corresponding to the end 21 a of the gas distribution chamber 21, and A portion corresponding to the arc-shaped portion of the end portion 22a of the exhaust gas recovery passage 22 is cut out in the same shape and opened to the lower surface. Therefore, the lower surface of the other part of the recessed groove formed in the support member 20 except 21a and 22a is closed and covered to form a pipe line for air supply or exhaust. Reference numeral 43 is a seal member that seals the connection between the supply or exhaust port and the gas distribution chamber or the exhaust recovery passage and the outside.

Although the opening of the gas ejection port 31 has a conical shape as described above, it is preferable that the bottom has an arcuate shape such that the bowl is laid down. However, it is difficult to implement the holding device due to the shape limitation that the whole holding device is a thin plate, but it is desirable to make the diameter as large as possible and to approach it. As shown in FIG. 7, if at least a concave groove around the ejection port is cut from the opposite side and is covered to secure the wall thickness of the opening, this can be slightly improved.

Reference numeral 60 denotes a drive mechanism composed of a rotary reactor attached to both sides of the joint 3 via L-shaped support fittings 61 and operated by compressed air or other pressure fluid. The output shaft 60a has a shaft joint 62. The rotary shaft 63 is connected via. The rotary shaft 63 rotatably penetrates both sides of the plate 1 along the extension direction of the plate 1, and controls a pressure source (not shown) connected to the input port 60 b of the drive mechanism 60. As a result, it can be rotated by 90 °. Reference numeral 24 is a pin that is planted through a collar 25 or the like at a position corresponding to the outer periphery of the peripheral edge of the object 7 of the rotary shaft 63. With the operation of the drive mechanism 60, the extension wall 3 as shown in FIG. It makes a reciprocating motion back and forth between a position parallel to and a position vertical. Reference numeral 26 is a notch provided at a position corresponding to the pin 24 of the plate-shaped body 2 for a space that allows the operation of the pin 24.

FIG. 11 shows a modification of the gas ejection port 31 of the embodiment shown in FIG. 1, which has one ejection port in FIG.
One end 21a of the gas distribution chamber 21 is branched into an X shape to form four pieces. This makes it suitable for objects with large area and unstable holding. The example shown is
Although the number of ejection ports is four, the number and arrangement can be increased or decreased in accordance with the shape or size of the object to be held. Although a rotary reactor is used as the drive mechanism of the rotary shaft 63, it can be driven by another rotary device, for example, a combination of a direct acting air cylinder and a rack gear or a crank, or a direct reduction motor.

[0021]

[Embodiment 2] FIGS. 12 to 15 show an embodiment different from the movable pin guide device in the above embodiment. In the figure,
The same components as those in the previous embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

In the figure, reference numeral 80 denotes a distribution passage formed of concave grooves cut from the upper surface side opposite to the concave grooves 21 and 22 on both side edges of the supporting member 20 along the extension direction of the plate-like body 2. Distribution channel 80
The end portion 80b on the side of the joint portion 4 is connected to the distribution passages 80 on both sides by overlapping the end portion with the end portion 80b, and a middle portion of the groove is cut from the lower surface of the support member 20 that bypasses the joint portion 4. A connecting path 81 is provided. The distribution passage 80 cut from the upper surface is covered with an upper lid member 82 slightly wider than the groove width of the concave groove, and the communication passage 81 is a thin plate member like the air supply passage 21 or the exhaust passage 22. It is covered by 30 and forms a common conduit. Plungers 83, 83, 8 that operate in a direction perpendicular to the extension wall 3 are provided at substantially both ends of the distribution passage 80, that is, in the vicinity of the overlapping portion of one of the concave grooves and at the other end.
A stopper control port 90 is provided in the communication path 81 including the parts 3 and 83 and extending to the joint part 4.

As is apparent from the sectional view of FIG. 15, the plunger 83 is made of a cylinder made of nylon or other low-friction resin material and having a large and small diameter, and has a large diameter portion 83.
a is slidably accommodated in a cylinder hole 84 formed in the support member 20, and the small-diameter portion 83c penetrates the thin plate member 30 in a freely fit manner. Further, on the end face of the large diameter portion 83a, the protrusion 83b
Equipped with. Here, the small diameter portion 83c regulates the position of the object 7, and the step with the large diameter portion engages with the through hole of the thin plate member 30 and regulates the stroke of the plunger 83. The projection 83b secures the pressure receiving surface of the plunger 83.

Although not shown, the stopper control port 90 is connected to a required gas pressure source or vacuum source through a gas control circuit that controls the supply and exhaust of both the air supply port 50 and the exhaust port 51. The pressurized or depressurized gas passes through the communication passage 81 and the distribution passage 80, and the cylinder hole 8
4, the plunger 83 is pushed out or retracted. The lengths and depths of the plunger 83 and the cylinder hole 84 are determined by design so that the tip of the small diameter portion 83c projects from the extension wall 3 when pressure is applied and the tip is buried in the plate-like body 2 when pressure is reduced. To do.

[0025]

EFFECTS OF THE INVENTION The present invention has the above-mentioned structure, and thus has the following effects.

An exhaust gas recovery port is arranged on a line surrounding the ejection port for each one or one group of the extension wall, and the gas ejected from the gas ejection port is forcibly passed through an exhaust gas recovery circuit connecting the exhaust gas recovery port and the exhaust gas recovery port. Since it is collected, it is possible to prevent the ambient atmosphere in a clean room or the like from being disturbed.

Further, by forming the exhaust recovery port as a continuous or intermittent groove formed along the line surrounding the ejection port, not only can the ejection gas be efficiently recovered,
When a plurality of jet ports are provided, an effect of suppressing a decrease in the working area due to mutual interference of jet gases can be expected.

The gas distribution chamber and the exhaust gas recovery circuit are
Since it is formed by a loop-shaped groove that is formed by connecting a required port to a plate-shaped member that is integral with or supports the extension wall and the gas ejection port, and a thin plate member that covers the groove, it is retained. Since the height of the apparatus main body can be kept extremely small, it is possible to handle a narrow space of a processing machine or a rack of a cassette.

Further, a pin capable of projecting outside the extension wall surface and a drive mechanism for driving the pin from a position where the pin is buried in the plate-shaped member to a position where it can project outside the extension wall surface are provided at any position on the extension wall surface. Since the holding object can be easily inserted into the remaining narrow space where the object is placed, and the object can be positioned by operating the pin after insertion, the height of the main body described above can be increased. Combined with the effect of suppressing the size, the effect on the narrow space becomes remarkable.

In this movable pin stopper device, a rotation angle within a range in which a pin provided on a rotary shaft penetrating along the extension wall of the plate member can be projected from the position where the pin is buried in the plate member to the outside of the extension wall. It becomes possible to carry out by repeatedly rotating at.

Further, the movable pin stopper device is a plunger type air cylinder having a size and a width such that the movable pin stopper is buried in the plate-like body when the total length is reduced, and the working end thereof projects from the extension wall surface when extended. Although the structure can be made simpler than the movable pin stopper device described above, consideration must be given to using, for the material of the plunger, nylon or other low friction resin material capable of withstanding high-frequency repetitive operation.

[Brief description of drawings]

FIG. 1 is a plan view showing a first embodiment of a contactless holding device.

FIG. 2 is a front view showing a first embodiment of a non-contact holding device.

FIG. 3 is a side view showing a first embodiment of a non-contact holding device.

FIG. 4 is a bottom view showing the first embodiment of the non-contact holding device.

5 is a cross-sectional view taken along the line AA of FIG. 1 and enlarged and shown.

6 is a cross-sectional view taken along the line BB of FIG. 1 and enlarged and shown.

FIG. 7 shows an example of forming a gas ejection port different from that shown in FIG.

FIG. 8 is a cross-sectional view taken along the line C-C of FIG. 1 and shown enlarged.

9 is a cross-sectional view taken along line D-D of FIG. 1 and enlarged and shown.

FIG. 10 is a cross-sectional view taken along line EE of FIG. 1 and enlarged.

FIG. 11 is a plan view similar to FIG. 1 with four body ejection ports.

FIG. 12 is a plan view showing a second embodiment of the non-contact holding device.

FIG. 13 is a front view showing a second embodiment of the non-contact holding device.

14 is a cross-sectional view taken along the line AA of FIG. 11 and enlarged.

FIG. 15 is a cross-sectional view taken along the line BB of FIG. 11 and enlarged and shown.

[Explanation of symbols]

 1 holding device 2 plate-like body 20 support member 21 gas distribution chamber 22 exhaust gas recovery circuit 22a exhaust gas recovery port 24 pin 25 notch 3 extension wall 30 thin plate member 31 gas ejection port 4 joint 40 joint fixing member 41 joint support member 50 air supply Port 51 Exhaust gas recovery port 60 Drive mechanism 62 Rotating shaft 7 Object to be held 83 Plunger 83b Spacer 90 Stopper control port

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H01L 21/68 A 8418-4M

Claims (8)

[Claims] 1. A gas ejection port, the diameter of which expands toward one or a plurality of openings, an extension wall connected to the periphery of the opening of the gas ejection port, and the gas ejection port and an air supply source. A gas distribution chamber communicating with the air supply port is formed, and by ejecting gas from the gas ejection port, a space where a negative pressure and a positive pressure are balanced is formed between the holding object and the extension wall. A holding device for holding the object to be held in a non-contact manner by connecting the exhaust recovery port and the exhaust recovery port, which are arranged on a line surrounding the ejection port of each of the extension walls for every one or one group. A contactless holding device comprising an exhaust gas recovery circuit. 2. The exhaust gas recovery port is a continuous or intermittent recessed groove formed along a line surrounding the ejection port, and the exhaust gas recovery circuit has an opening provided at an arbitrary position on the bottom of the recessed groove. The contactless holding device according to claim 1, wherein the contactless holding device is a conduit communicating with the air supply port. 3. The gas distribution chamber and the exhaust gas recovery circuit have a loop-shaped groove formed by connecting a required port to a plate-like member which is integral with or supports the extension wall and the gas ejection port, and the groove. The non-contact holding device according to claim 1, wherein the non-contact holding device comprises a plate-shaped body formed of a thin plate member to be covered. 4. An object to be held, which includes a gas ejection port whose diameter is enlarged toward the opening and an extension wall which is continuous with a peripheral edge of the opening of the gas ejection port, and ejects gas from the gas ejection port. Is a holding device for holding a holding object in a non-contact manner by forming a space in which a negative pressure and a positive pressure are balanced between the extension wall and the extension wall, and can protrude outside the extension wall surface at an arbitrary position on the extension wall surface. Non-contact holding device including a movable pin stopper device including a pin, and a driving mechanism that drives the pin from a position where the pin is buried in the plate-shaped member to a range in which it can project to the outside of the extended wall surface. . 5. The movable pin stopper device comprises a rotary shaft penetrating along an extension wall of the plate-shaped member, a pin radially implanted at an arbitrary position of the rotary shaft, and one end of the rotary shaft. 5. The drive mechanism is configured to be repeatedly rotated at a rotation angle within a range in which the pin provided in the portion is embedded in the plate-shaped member and can be projected to the outside of the extended wall surface.
The contactless holding device described in. 6. A plunger-type air cylinder in which the movable pin stopper device is connected to at least one externally controllable common port which is located at an arbitrary position on the extension wall surface and which is vertically arranged on the extension wall surface. The air cylinder is embedded in the plate-like body when the total length is reduced at the longest,
The contactless holding device according to claim 4, wherein the contact end has a size and a size such that its working end projects from the extension wall surface when extended. 7. A blind hole bored in a thickness direction of a plate-shaped member opened toward an extension wall surface at an arbitrary position, a groove connecting the blind hole and an air supply port, and a shaft for the blind hole. Between the plunger and the other end of the plunger and the bottom of the blind hole, the length of which is slidably inserted in the direction close to the depth of the blind hole. The contactless contact according to claim 6, further comprising: a spacer having a minute length, the thin plate member having a small hole corresponding to a position of the plunger and a diameter of a small diameter portion, and serving as a stopper for preventing the plunger from falling and a lid for the groove. Holding device. 8. The contactless holding device according to claim 7, wherein the plunger is made of nylon or another low friction resin material, and the spacer is a small projection formed on an end surface opposite to the small diameter portion.