JP2004076916A - Differential pumping seal apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a differential pumping seal apparatus capable of surely blocking one space constituting a purification space from other spaces to prevent contamination of the purification space even when a function of the differential pumping seal stops or has stopped. <P>SOLUTION: There is provided with a differential pumping seal 40 for sealing a clearance between a first member 11 defining at least one space of a first space and a second space with different atmospheres and a second member 21 relatively movable to the first member, and between the first space and the second space in a non-contact condition. Also, there is provided with a tangible sealing element contacting with both of the first and second members to block the first space from the second space only when a function of the differential seal stops or has stopped. The tangible sealing element is constituted from an extensible diaphragm-like sealing member 54 projecting to the second member side and contacting with the second member in response to a fluid pressure action with its peripheral part fixed to the first member. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
[Industrial applications]
The present invention relates to, for example, a differential exhaust seal device that constitutes a part of a semiconductor manufacturing apparatus, and in particular, for example, one space defined by a fixed member and a movable member with respect to the fixed member, A sealing element called a differential pumping seal suitable for sealing a gap between the space and another space having a different atmosphere (pressure, cleanliness, type of gas, etc.) without contact. The present invention relates to an improvement of a differential exhaust seal device provided with:
[0002]
[Prior art]
For the differential exhaust seal, "Air Bearing Vacuum Seal Assembly" of U.S. Pat. No. 4,118,042 (filed in 1977) and "Vacuum sealed" of U.S. Pat. No. 4,191,358 (filed in 1979) were used. Gas bearing Assembly, etc., and an example applied to a semiconductor manufacturing apparatus is known in "Electron beam Lithographic Apparatus" of U.S. Pat. No. 4,425,508 filed in 1982.
Such a conventionally known differential exhaust seal is used to move an object (rotational motion, linear motion) in a clean space represented by a vacuum space at a high speed without contaminating the clean space. It has been used for smooth implementation.
There are at least two directions in which it is used.One is that the drive source and guide mechanism for movement are placed outside the clean space, and only the minimum structure and the sample to be moved are placed inside the clean space. The second is the case where two spaces are sealed without impairing the merits of the non-contact bearing when using a hydrostatic bearing (for example, an air bearing). In this case, as “two spaces”, 1) the bearing is performed in the clean space and the space where the bearing fluid exists and the clean space are sealed, and 2) the bearing is performed outside the clean space and the clean space and There is a case where the outside is sealed.
[0003]
[Problems to be solved by the invention]
The differential exhaust seal can separate the two spaces in a non-contact state. This feature is fully understood as an advantage and tends to be applied to specific devices. In a steady state in which the differential exhaust seal is functioning, there is certainly an advantage of having an excellent function of a non-contact seal. However, from a comprehensive point of view, such as the reliability, life, and cleanliness of the specific equipment, it is necessary to fully understand the effects (characteristics) of when the differential exhaust seal is not functioning, that is, in the unsteady state. There is.
[0004]
Assuming the operation of a device equipped with a differential exhaust seal, there are cases where the sealing function cannot be continued (for example, at the time of an emergency stop of the device) and when the entire device is suspended. At this time, there is a demerit because the differential exhaust seal is a non-contact seal. This is easy to imagine, because the invisible wall separating the two spaces disappears when the sealing function stops. For example, when the differential exhaust seal, which separates a clean space (in vacuum) and a space outside (in the air) in a non-contact manner, suddenly stops operating, the air in the air is instantly clean. Fills the vacuum space.
Usually, to improve the degree of vacuum, the most influential substance is moisture, which is the humidity of the atmosphere. Normal humidity in a clean room is about 40 to 55%, and contains a lot of moisture. In a device in which the air flows into the clean room every time the differential exhaust seal stops functioning, it is difficult to improve the degree of vacuum in the vacuum chamber to be cleaned. In addition, it cannot be denied that particles in the atmosphere outside the vacuum chamber are mixed. In an apparatus having a normal vacuum chamber, the atmosphere is not introduced into the vacuum chamber, and the humidity of the gas to be introduced is controlled to be extremely low.
[0005]
Thus, in the state where the function of the non-contact seal is stopped in the differential exhaust seal, it is the same as a vacuum chamber with a large crack in the partition partitioning from the outside, and from a common sense standpoint of the conventional vacuum equipment field, Device. "
As described above, the non-contact seal typified by the differential exhaust seal conventionally used has an inherent disadvantage in operation of a device requiring a clean space (for example, vacuum). .
In order to apply a non-contact seal to an actual semiconductor manufacturing apparatus, it is necessary to compensate for these operational disadvantages by adding other elements.
[0006]
Therefore, an object of the present invention is to reliably shut off one space constituting a clean space from another space to prevent contamination of the clean space even when the function of the differential exhaust seal is stopped or stopped. It is an object of the present invention to provide a differential exhaust seal device that can prevent such a problem.
Another object of the present invention is a differential exhaust seal device for sealing a gap formed between two spaces having different atmospheres with a differential exhaust seal, wherein the differential exhaust seal is functioning ( (Steady state) does not work, and when it does not work (unsteady state), it operates by the action of fluid pressure and comes into contact with the member that defines the gap to interrupt the communication between the two spaces. An object of the present invention is to provide a differential exhaust sealing device including a member.
Another object of the present invention is a differential exhaust seal device for sealing a gap formed between two spaces having different atmospheres with a differential exhaust seal, wherein the differential exhaust seal is functioning ( The stationary state) does not operate, and when it does not function (unsteady state), one of the two members defining the gap is pressed toward the other of the members by the pressing means, and one of the members contacts the sealing member. And thereby providing a differential exhaust seal device that blocks communication between the two spaces.
[0007]
[Means for Solving the Problems]
The invention of the present application is directed to a first member that defines at least one of a first space and a second space having different atmospheres, and a second member that is relatively movable with respect to the first member. A differential exhaust seal device having a differential exhaust seal for sealing a gap in a non-contact state between the first space and the second space in a non-contact state, A tangible sealing element that contacts the first and second members only to shut off the first space and the second space only when the function is stopped or when the function is stopped; An extension of the tangible sealing element of the exhaust sealing device, the peripheral portion of which is fixed to the first member and projects toward the second member under the action of fluid pressure to come into contact with the second member; It consists of a possible diaphragm-shaped sealing member.
By configuring the differential exhaust seal device as described above, according to the present invention, even when the function of the differential exhaust seal is stopped or stopped, the communication between the first and second spaces is effective. Can be shut off. Further, the diaphragm-shaped sealing member has a structure capable of performing its function without supplying energy when performing the sealing function, and can maintain the sealing function in a state of contact (a state with a low energy level).
In the differential exhaust seal device, a gap is formed on both sides of the second member, and the differential exhaust seal for sealing the gap in a non-contact state is provided on at least two opposite sides of the second member. May be provided. Further, the differential exhaust seal device further includes a static pressure bearing functioning in the gap, wherein the static pressure bearing and the differential exhaust seal are adjacent in the gap and the static pressure bearing is on the other space side. And the tangible sealing element may be disposed between the hydrostatic bearing and the other space.
[0008]
Another invention of the present application is directed to a first member that defines at least one of a first space and a second space having different atmospheres, and a second member that is relatively movable with respect to the first member. A differential exhaust seal device provided with a differential exhaust seal for sealing a gap between the first space and the second space in a non-contact state. A tangible sealing element that contacts the first and second members only and shuts off the first space from the second space only when or when the function of the seal is stopped, A gap is formed only on one side of the second member, the one space is defined by the first member and the second member, and the tangible sealing element is fixed to the first member. A fixed sealing member that is in contact with the second member. The differential exhaust seal device further pushes the second member toward the first member side only when the function of the differential exhaust seal is stopped or stopped, and pushes the second member to the second member. It is provided with a pressing means for making it contact with the fixed seal member.
By configuring the differential exhaust seal device as described above, according to the present invention, even when the function of the differential exhaust seal is stopped or stopped, the communication between the first and second spaces is effective. Can be shut off. Further, the fixed seal member has a structure capable of performing its function without supplying energy when performing the sealing function, and can maintain the sealing function in a state of contact (a state with a low energy level).
The differential exhaust seal device further includes a static pressure bearing functioning in the gap, wherein the static pressure bearing and the differential exhaust seal are adjacent in the gap and the static pressure bearing is on the other space side. And the tangible sealing element may be disposed between the hydrostatic bearing and the other space.
[0009]
【Example】
Hereinafter, a first embodiment of a differential exhaust seal device of the present invention will be described with reference to the drawings. In this embodiment, an example using a differential exhaust seal and a static pressure bearing will be described with reference to a simplified drawing.
1 to 3, a first embodiment of the differential exhaust sealing device of the present invention is indicated by reference numeral 10 as a whole. In the figure, reference numeral 11 denotes a first member which defines a first space 1 which can constitute a clean space, and the outer peripheral side of the member 11 (only shown on the left side in FIGS. 1 and 2) is the first space. A second space having a different atmosphere (pressure, cleanliness, filling gas type, and the like), for example, an atmospheric pressure space 2 is provided. In the side wall 12 of the first member 11, a passage 13 that communicates the first space 1 and the second space 2 defined by the first member is formed through the side wall, and the passage 13 is formed through the passage 13. The second member 21 is disposed. The first member 11 is a housing defining a first space 1 (for example, a vacuum chamber), and the second member 21 is a slider capable of relatively linear movement (in FIGS. 1 and 2) with respect to the housing. possible. Therefore, hereinafter, the first member will be described as a housing and the second member will be described as a slider. The slider 21 has a rectangular cross section in this embodiment, and therefore the passage 13 for receiving the slider 21 is also rectangular. A gap g having a desired size, for example, about 5 to 50 μm is formed between the slider 21 and the housing 11 so that the slider 21 can move without contact with the housing 11.
[0010]
On the inner peripheral surface 14 that defines the passage 13 formed in the housing 11, a groove 31 that forms the hydrostatic bearing 30 is formed at a position near the second space 2 side. The groove 31 extends all around the circumference of the passage 13 so as to surround the slider 21, but only the upper and lower portions of the inner peripheral surface 14 are shown in FIGS. 1 and 2. The groove 31 is connected to a supply source 35 of clean air or clean inert gas through an on-off valve 32 so that clean air or inert gas can be supplied into the groove 31. A plurality of (three in this embodiment) grooves 41 forming the differential exhaust seal 40 are formed on the inner peripheral surface 14 between the groove 31 and the first space 1. The groove 41 also extends so as to surround the outer periphery of the slider 21 in the circumferential direction of the passage 13, but only the upper and lower portions of the inner peripheral surface 14 are shown in FIGS. 1 and 2. The groove 41 is connected to a vacuum source (not shown) (including a vacuum tank, a vacuum pump, and the like) 45 via an on-off valve 42 so that gas flowing in the gap is discharged through these grooves.
[0011]
On the inner peripheral surface 14 of the passage 13, a groove 51 is further formed between the groove 31 of the hydrostatic bearing 30 and the space 2. The groove 51 also extends all around the circumference of the passage 13 so as to surround the slider 21. The groove 51 is connected to a supply source 55 of a fluid such as a gas or a liquid via an on-off valve 52 so that a gas or a liquid can be supplied into the groove 51. A diaphragm-shaped sealing member 54 having a substantially U-shaped or V-shaped cross section is arranged in the groove 51, and both end edges of the sealing member are fixed to the passage-side open end of the groove 51 by a known method. When the fluid is not supplied into the groove 51, the seal member 54 has a shape to be retracted into the groove 51 as shown in FIG. The material of the diaphragm-shaped seal member is preferably a fluorine-based, silicon-based, butyl acetate-based resin or rubber.
[0012]
In the differential exhaust seal device having the above-described configuration, the slider 21 is capable of linearly reciprocating in the horizontal direction (left and right directions in FIGS. 1 and 3) by a driving mechanism (not shown) disposed in the space 2 under atmospheric pressure. I have. By moving the slider, a sample piece or the like can be moved in the first space.
When the on-off valve 32 is opened and clean air or clean inert gas is supplied into the groove 31 of the static pressure bearing 30 from the clean air or clean inert gas supply source 35, the air or gas flows from the groove 31 to the gap g. And holds the slider 21 in a state where the slider 21 is not in contact with the housing 11 (non-contact state). Therefore, the slider 21 is smoothly reciprocated by the driving mechanism (not shown) in a non-contact state with the housing. Most of the air or gas flowing into the gap g flows from the plurality of grooves 41 of the differential exhaust seal 40 into the negative pressure source 45 via the on-off valve, and the remaining part is the second under atmospheric pressure. Flows in space. Therefore, only a small amount of air or gas flows into the first space 1 as a clean space. In such a state, the first space 1 and the second space 2 are separated by an invisible wall (a non-contact seal, that is, a differential exhaust seal).
In the above-described embodiment, one of the three grooves 41 of the differential exhaust seal on the first space side may be used as a purge gas port without being used for exhaust.
[0013]
When the on-off valve 32 of the static pressure bearing 30 is closed and the supply of clean air or clean inert gas into the groove 31 is stopped or / and stopped, the on-off valve 32 of the differential exhaust seal device 40 Is also closed, and the evacuation of air or gas in the gap g from the groove 31 is stopped. Simultaneously with or immediately after the on-off valve 32 is closed, the on-off valve 52 is opened and the fluid is sent into the groove 51. As a result, the diaphragm-shaped sealing member 54 is deformed so that the central portion protrudes out of the groove 51 as shown in FIG. 2, and the sealing member comes into contact with the outer surface 22 of the slider. Therefore, communication between the first space 1 and the second space 2 via the gap g is blocked by the seal member 54. Therefore, the degree of vacuum or cleanliness in the second space 2 is slightly lower than when the differential exhaust seal is operating, but is significantly reduced so as to hinder the operation of the device equipped with the differential exhaust seal device. I will not. After the communication between the first space and the second space is cut off by the seal member 54 as described above, a highly clean gas may be supplied into the first space.
In the above-described embodiment, the case where the cross-sectional shape of the slider 21 and the passage 13 is rectangular is described. However, the cross-sectional shape of the slider and the passage may be circular, elliptical, or the like.
[0014]
FIGS. 4 to 6 show a second embodiment of the differential exhaust seal device of the present invention. Note that components corresponding to the first embodiment are denoted by the same reference numerals with a suffix a, and detailed descriptions of components having the same structure and function are omitted, and only different components are described in detail. I do.
In the figure, reference numerals 11a and 11a 'denote first members as housings that define a first space 1 that can constitute a clean space, and 21a is a relative member with respect to the housings 11a and 11a' (in FIG. 4, left and right directions). A) a second member as a possible slider. In this embodiment, there are two housings, the housing 11a is arranged above the slider 21a, and the housing 11a 'has a part arranged below the slider. The outer peripheral side of the housings 11a and 11a '(only shown on the left side in FIG. 4) is a second space having a different atmosphere (pressure, cleanliness, type of filling gas, etc.) from the first space, for example, an atmospheric pressure space 2 It has become.
The static pressure bearing and differential exhaust seal provided between the housing 11a and the slider 21a are substantially the same as the static pressure bearing and differential exhaust seal provided between the housing 11a 'and the slider 21a. Therefore, only the former will be described.
[0015]
In this embodiment, the side wall 12a of the housing 11a extends in a ring shape (a rectangular ring if the housing is rectangular, or a ring if the housing is circular) so as to surround the first space 1 above the slider. The lower edge surface 14a of the side wall 12a is separated from the slider by a desired distance over the entire circumference, and a gap g having a desired size, for example, about 5 to 50 μm is formed between the lower edge surface and the slider. Therefore, the slider 21a can move without contact with the housing 11a.
On the lower edge surface 14a of the housing 11a, a groove 31a forming the hydrostatic bearing 30a is formed at a position near the second space 2 side. The groove 31a extends over the entire circumference in the extending direction of the lower edge surface so as to surround the second space, but only a part thereof is shown in FIG. The groove 31a is connected to a supply source 35a of clean air or clean inert gas via an on-off valve 32a so that clean air or inert gas can be supplied into the groove 31a. On the lower edge surface 14a, a plurality (three in this embodiment) of grooves 41a forming the differential exhaust seal 40a are formed between the groove 31a and the first space 1. The groove 41a also extends over the entire circumference in the direction in which the lower edge surface extends, so as to surround the second space. The groove 41a is connected to a vacuum source (not shown) (including a vacuum tank, a vacuum pump, etc.) 45a via an open / close valve 42a, and discharges gas flowing in the gap through these grooves.
[0016]
A diaphragm-shaped seal member 54a is further disposed on the lower edge surface 14a between the groove 31a of the hydrostatic bearing 30a and the outer periphery of the side wall 12a. This seal member 54a also extends over the entire circumference in the direction in which the lower edge surface extends, like the groove 31a, so as to surround the first space. Both edges of the seal member are fixed to the lower edge surface 14a by a known method. When the fluid is not supplied into the fluid passage 53a opened at a substantially intermediate position of the seal member 54a, the side wall 12a is flat as shown in FIG. 3 and is in contact with the lower edge surface 14a. The state that has been maintained. The diaphragm-shaped sealing member is also preferably made of a resin, rubber, or the like based on a fluorine, silicon, or butyl acetate system.
The operations of the static pressure bearing 30a and the differential exhaust seal 40a are the same as in the above embodiment. When the on-off valve 32a of the static pressure bearing 30a is closed and the supply of the clean air or the clean inert gas into the groove 31a is stopped or / and is stopped, the on-off valve 42a of the differential exhaust seal device 40a. Is also closed to stop the exhaust of the air or gas in the gap g from the groove 41a. Simultaneously with or immediately after the closing of the on-off valve 32a, the on-off valve 52a is opened and the fluid flows into the rear side of the diaphragm-shaped sealing member 54a. Therefore, as shown in FIG. And contacts the outer surface 22a of the slider. For this reason, communication through the gap g between the first space 1 and the second space 2 is blocked by the seal member 54a. Other operations are the same as those of the first embodiment.
In the embodiment shown in FIG. 4, the mounting surface of the seal member 54a is flush with the lower edge surface. However, as shown in FIG. 7, the mounting surface is retracted by the thickness of the seal member 54a. The outer side surface may be flush with the lower edge surface.
Furthermore, even if the seal member of the second embodiment is applied to the differential exhaust seal device of the first embodiment, the seal member of the first embodiment is also applied to the differential exhaust seal device of the second embodiment. May be applied.
[0017]
FIG. 8 shows a third embodiment of the differential exhaust sealing device of the present invention. Components corresponding to the first embodiment are denoted by the same reference numerals with a suffix b, and detailed descriptions of components having the same structure and function will be omitted, and only different components will be described in detail. .
In the figure, reference numeral 11b denotes a first member as a housing that defines a first space 1 that can form a clean space together with a second member 21b as a slider. The outer peripheral side of the member 11b is a second space having a different atmosphere (pressure, cleanliness, type of filling gas, etc.) from the first space, for example, a space 2 at atmospheric pressure. In this embodiment, the housing is arranged only on one side of the slider (upper side in FIG. 6). The drive mechanism for the slider is disposed in the second space as in the above-described embodiment, and can move a sample piece or the like in the first space by moving the slider.
In this embodiment, the side wall 12b of the housing 11b extends annularly (in the case of a rectangular housing, in the shape of a rectangular ring, and in the case of a circular housing, in an annular shape) so as to surround the first space 1 above the slider. The lower edge surface 14b of the side wall 12b is separated from the slider by a desired distance over the entire circumference, and a gap g having a desired size, for example, about 5 to 50 μm is formed between the lower edge surface and the slider. Therefore, the slider 21b can move without contact with the housing 11b.
[0018]
On the lower edge surface 14b of the housing 11b, similarly to the second embodiment, a plurality of (three in this embodiment) grooves 41b forming the hydrostatic bearing 30b and a plurality of (three in this embodiment) grooves forming the differential exhaust seal 40b are formed. Is formed. Further, a fixed sealing member 54b is fixed to the lower edge surface 14b between the groove 31b of the hydrostatic bearing 30b and the outer periphery of the side wall 12b so as to protrude from the lower edge surface. The fixed seal member is not deformed under the action of fluid pressure as in the above two embodiments to contact with the slider, but does not receive any action of fluid pressure, and the slider is not affected by fluid pressure as described below. A seal member having a function of contacting the slider by being pushed by the housing. Specifically, a so-called O-ring seal having a circular cross section may be used, but a seal member having another shape may be used as long as it has the above-described function. In FIG. 8, the fixed seal member 54b is shown only on the left and right lower edge surfaces of the housing, but since the side wall 12b is formed so as to surround the first space 1, this fixed seal member is also formed on the side wall. It is arranged endlessly over the entire lower edge surface. The material of the fixed sealing member is preferably a fluorine-based, silicon-based, butyl acetate-based resin or rubber.
A pressing device 60b is disposed below the slider 21b at a position corresponding to the position of the fixed seal member separated in the moving direction of the slider. The pressing device 60b has a plunger 62b elastically pressed to the housing side by a spring 61b, and a roller 63b that contacts the lower surface of the slider 21b is rotatably provided at the upper end (end on the slider side) of the plunger by a known method. Fixed. Therefore, the slider 21b linearly reciprocates right and left in FIG. 8 while contacting the roller 63b.
[0019]
In the differential exhaust seal device having the above structure, the operations of the static pressure bearing 30b and the differential exhaust seal 40b are the same as those in the above-described embodiment. That is, when the open / close valve 32b is opened and clean air or clean inert gas is supplied into the groove 31b of the static pressure bearing 30b from the clean air or clean inert gas supply source 35b, the air or gas is supplied from the groove 31b. It flows into the gap g and pushes the slider 21 away from the housing against the pressing by the pressing device 60b. For this reason, the slider 21b is held in a state (non-contact state) not in contact with the fixed seal member 54b fixed to the lower edge surface of the housing 11. Therefore, the slider 21b is smoothly reciprocated by the driving mechanism (not shown) in a non-contact state with the housing. Most of the air or gas that has flowed into the gap g flows from the plurality of grooves 41b of the differential exhaust seal 40b into the negative pressure source 45b via the on-off valve, and the remaining part is at the second pressure under atmospheric pressure. Flows in space. Therefore, only a small amount of air or gas flows into the first space 1 as a clean space. In such a state, the first space 1 and the second space 2 are separated by an invisible wall (a non-contact seal, that is, a differential exhaust seal).
In the above-described embodiment, one of the three grooves 41 of the differential exhaust seal on the first space side may be used as a purge gas port without being used for exhaust.
[0020]
When the on-off valve 32b of the static pressure bearing 30b is closed and the supply of clean air or clean inert gas into the groove 31b is stopped or / and stopped, the on-off valve 32b of the differential exhaust seal device 40b is stopped. Is also closed to stop the exhaust of the air or gas in the gap g from the groove 31b. For this reason, the action of the fluid pressure in the gap g is eliminated, and the slider 21b is pushed up to the housing 11b side by the action of the spring 61b of the pressing device 60b (as shown by a dashed line in FIG. 8), and the upper surface 22b is fixed to the fixed seal member 54b. Abut. For this reason, communication via the gap g between the first space 1 and the second space 2 is blocked by the seal member 54b. Therefore, the degree of vacuum or cleanliness in the second space 2 is slightly lower than when the differential exhaust seal is operating, but is severely reduced so as to hinder the operation of the device equipped with the differential exhaust seal. I will not.
[0021]
【The invention's effect】
According to the present invention, the differential exhaust seal device is provided with a diaphragm type seal member that operates by the action of fluid pressure, or a fixed seal member that functions by pressing one member against the other member with a pressing device. Is provided, a device provided with a non-contact seal typified by a differential exhaust seal (for example, a semiconductor manufacturing device) can be made a device with excellent characteristics. That is, it is possible to maintain the cleanliness in the clean space (vacuum chamber) at the time of emergency stop or suspension of the apparatus, and to improve the vacuum arrival speed at the time of restarting the apparatus.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view of a first embodiment of the differential exhaust seal device of the present invention.
FIG. 2 is a view taken along line AA in FIG. 1;
FIG. 3 is a view showing different operation states of the differential exhaust seal device shown in FIG. 1;
FIG. 4 is a partial sectional view of a second embodiment of the differential exhaust sealing device of the present invention.
FIG. 5 is a perspective view showing the entirety of a housing and a slider provided with the differential exhaust seal device of the second embodiment.
FIG. 6 is a diagram showing different operation states of the differential exhaust seal device shown in FIG. 4;
FIG. 7 is an enlarged sectional view showing a modification of the method of attaching the diaphragm type seal member.
FIG. 8 is a sectional view of a third embodiment of the differential exhaust seal device of the present invention.
[Explanation of symbols]
1 First space 2 Second space
11, 11a, 11b First member (housing)
21, 21a, 21b Second member (slider)
30, 30a, 30b Static pressure bearing
40, 40a, 40b Differential exhaust seal
54, 54a diaphragm seal member
54b Fixed sealing member

Claims (4)

A gap between a first member defining at least one of a first space and a second space having different atmospheres, and a second member relatively movable with respect to the first member; A differential exhaust seal device including a differential exhaust seal for sealing a gap between a first space and the second space in a non-contact state,
A tangible sealing element that contacts the first and second members to block the first space from the second space only when the function of the differential exhaust seal is stopped or only when the function of the differential exhaust seal is stopped. With
The tangible sealing element has a peripheral portion fixed to the first member, and is extensible diaphragm-shaped projecting toward the second member and coming into contact with the second member under the action of fluid pressure. A differential exhaust sealing device, which is a sealing member. The differential exhaust seal device according to claim 1,
The differential exhaust, wherein the gap is formed on both sides of the second member, and the differential exhaust seal for sealing the gap in a non-contact state is provided on at least two opposite sides of the second member. Sealing device. A gap between a first member defining at least one of a first space and a second space having different atmospheres, and a second member relatively movable with respect to the first member; A differential exhaust seal device including a differential exhaust seal for sealing a gap between a first space and the second space in a non-contact state,
A tangible sealing element that contacts the first and second members to block the first space from the second space only when the function of the differential exhaust seal is stopped or only when the function of the differential exhaust seal is stopped. With
The gap is formed only on one side of the second member, and the one space is defined by the first member and the second member;
The tangible sealing element is a fixed sealing member fixed to the first member and capable of contacting the second member;
The differential exhaust seal device further presses the second member toward the first member side only when the function of the differential exhaust seal is stopped or is stopped, so that the second member is fixedly sealed. A differential exhaust sealing device including a pressing device that contacts a member. The differential exhaust seal device according to any one of claims 1 to 3,
A static pressure bearing functioning in the gap, wherein the static pressure bearing and the differential exhaust seal are arranged adjacent to each other in the gap and the static pressure bearing is on the other space side; A differential exhaust sealing device, wherein the sealing element is disposed between the hydrostatic bearing and the other space.

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