JP5151492B2 - Rotary joint - Google Patents

Description

  The present invention relates to a rotary joint that connects a rotating tube and a non-rotating tube that supplies a cleaning solution or a polishing solution for cleaning or polishing the surface of a silicon wafer, for example.

Japanese Patent Application Laid-Open No. 2004-84691 Japanese Patent No. 2918874 Japanese Patent No. 3072349 Japanese Patent No. 3098236

  In a cleaning device or a surface polishing device that cleans or polishes the surface of a silicon wafer, a non-rotating tube and a rotating tube in a pipe that supplies pure water or slurry fluid containing nitrogen gas as a cleaning liquid, for example, a polishing liquid, are connected. A mechanical seal with frictional contact is used for the rotary joint.

  Various rotary joints having such a mechanical seal have been proposed as is apparent from the descriptions of Patent Documents 1 to 4.

  By the way, if a mechanical seal with frictional contact is used at a portion where a non-rotating tube and a rotating tube are connected in a rotary joint, wear powder is generated and mixed with pure water or polishing liquid. Cleaning or polishing the surface of a silicon wafer with water or a polishing liquid will adversely affect the quality of the silicon wafer, and silicon wafers that have been cleaned or polished using a rotary joint are increasingly required to have higher density. There is a possibility that the device cannot be used.

  The present invention has been made in view of the above-mentioned points, and the object of the present invention is to eliminate generation of wear powder at a portion connecting the non-rotating tube and the rotating tube, passing pure water, washing It is possible to eliminate contamination of wear powder in fluids such as liquid, nitrogen gas, a mixture of pure water and nitrogen gas, or a mixture of cleaning liquid and nitrogen gas, and if necessary, metal ions in the fluid. An object of the present invention is to provide a rotary joint that can eliminate the occurrence of the above.

  A rotary joint according to the present invention includes a hollow member having a hollow portion therein and a fluid introduction hole communicating with the hollow portion on the one end surface side in the axial direction, and the hollow portion side of the fluid introduction hole of the hollow member The open end of the hollow member has one open end in the axial direction facing with a gap, and has a protruding end protruding outside from the other end surface in the axial direction of the hollow member, and is attached to the hollow portion of the hollow member A hollow rotating shaft member, and a contact type that is interposed between the hollow member and the hollow rotating shaft member at a hollow portion of the hollow member and that allows the hollow rotating shaft member to rotate with respect to the hollow member about an axis. A cylindrical inner peripheral surface of the hollow member defining a hollow portion positioned between the bearing and the one open end of the hollow rotary shaft member in the axial direction, and a cylindrical outer peripheral surface of the hollow rotary shaft member Supply high-pressure gas to the cylindrical gap between A high pressure gas supply means, and a high-pressure gas discharge means for discharging high-pressure gas supplied to the cylindrical gap together is arranged between the high pressure gas supply means and the bearing to the outside in the axial direction.

  According to the rotary joint of the present invention, since one open end of the hollow rotary shaft member and one end on the hollow portion side of the introduction hole of the hollow member face each other with a gap, generation of friction powder here is eliminated. In addition, the cylindrical inner peripheral surface of the hollow member defining the hollow portion located between the one open end of the hollow rotary shaft member in the axial direction and the bearing, and the cylindrical outer peripheral surface of the hollow rotary shaft member High-pressure gas supply means for supplying high-pressure gas to the cylindrical gap between the two, and the high-pressure gas arranged in the axial direction between the high-pressure gas supply means and the bearing and discharged to the cylindrical gap is discharged to the outside Since the high-pressure gas discharge means is provided, the bearing, the introduction hole of the hollow member, and one open end of the hollow rotary shaft member can be isolated by a high-pressure gas layer made of high-pressure gas supplied to the cylindrical gap. , Led from the fluid introduction hole to the hollow part In addition, it is possible to prevent the friction powder generated in the contact-type bearing from being introduced into the fluid introduced into the hollow rotary shaft member through one open end, and to prevent the hollow member and the high-pressure gas layer from flowing into the static pressure gas. Since it can function as a bearing, the hollow rotary shaft member can be favorably rotatably supported in cooperation with such a static pressure gas bearing and a contact type bearing.

  In a preferred example, the hollow member includes a fluid introduction hole, an axially inner end face where the opening end of the fluid introduction hole on the hollow portion side is located, a cylindrical inner peripheral face connected to the inner end face, and an inner peripheral face connected to the inner peripheral face. A non-metallic lid member having an annular outer end surface in the axial direction, an annular end surface contacting the annular outer end surface in the axial direction of the lid member, and a cylindrical inner circumferential surface having a smaller diameter than the inner circumferential surface of the lid member And a synthetic resin cylindrical body having a cylindrical outer peripheral surface having a larger diameter than the inner peripheral surface of the lid member, and the hollow rotating shaft member has a small-diameter outer peripheral surface, which is larger than the outer peripheral surface. A cylindrical outer peripheral surface having a diameter and forming a narrow annular gap in the radial direction with the inner peripheral surface of the cylindrical body, and a through hole extending from one end surface in the axial direction to the other end surface in the axial direction And a hollow rotary shaft member main body having a projecting end projecting outward from the other axial end surface of the hollow member, An inner peripheral surface that is in contact with a small-diameter outer peripheral surface of the idling shaft member main body and is fitted to the small-diameter outer peripheral surface, and is larger in diameter than the inner peripheral surface and between the inner peripheral surface of the cylindrical body. A cylindrical outer circumferential surface that forms a narrow annular gap in the direction and a wide annular gap in the radial direction between the inner circumferential surface of the lid member and the opening on the hollow portion side of the fluid introduction hole of the lid member Non-metal having one axially open end facing with a gap at the end and having a through hole extending in the axial direction so as to communicate with the through hole of the hollow rotary shaft member body from the one open end A cover member made of metal, and an outer periphery that is inserted into both through holes of the cover member and the hollow rotary shaft member body and that contacts the cylindrical inner peripheral surface of the cover member and hollow rotary shaft member body that define both through holes And a hollow portion defining a hollow portion having a synthetic resin-coated tube having a surface The cylindrical inner peripheral surface includes the cylindrical inner peripheral surface of the lid member and the cylindrical inner peripheral surface of the cylindrical body, and the cylindrical outer peripheral surface of the hollow rotary shaft member is a hollow rotary shaft member. A shaft of a narrow annular gap that includes the cylindrical outer peripheral surface of the main body and the cylindrical outer peripheral surface of the covering member, and is formed by the inner peripheral surface of the cylindrical body and the outer peripheral surface of the hollow rotary shaft member main body. One end of the annular ring in the direction communicates adjacent to one end of the annular ring in the axial direction of the narrow annular gap formed by the inner peripheral surface of the cylindrical body and the outer peripheral surface of the covering member. The other end of the annular ring in the axial direction of the narrow annular gap formed by the inner peripheral surface of the cover member and the outer peripheral surface of the cover member is a wide width formed by the inner peripheral surface of the lid member and the outer peripheral surface of the cover member Of the annular gap in the axial direction of the wide annular gap formed by the inner peripheral surface of the lid member and the outer peripheral surface of the cover member. The other end of the annular ring communicates adjacent to the space between the inner end surface of the lid member and the axial end surface of the cover member in which one opening end of the through hole of the cover member is located, and supplies high-pressure gas The means is adapted to supply high-pressure gas to a narrow annular gap formed by the inner peripheral surface of the cylindrical body and the outer peripheral surface of the hollow rotary shaft member body, and the inner peripheral surface of the cylindrical body and the hollow rotation The other annular end in the axial direction of the narrow annular gap formed by the outer peripheral surface of the shaft member main body communicates with the high-pressure gas discharge means, and the inner end surface of the lid member and the through hole of the cover member A space between the end face in the axial direction of the covering member where one open end is located communicates with the fluid introduction hole and the inside of the cladding tube.

  According to such an example, even if the hollow rotary shaft member main body is made of metal, the fluid introduced into the hollow portion of the hollow member through the fluid introduction hole is substantially a non-metallic lid. It is introduced into the inside of the synthetic resin cladding tube from one open end of the hollow rotary shaft member through a space defined by the inner end surface and inner peripheral surface of the member and the axial end surface of the nonmetallic cover member. As a result, it is possible to eliminate the generation of metal ions due to the metal contact by contacting only the non-metallic surface in such introduction, and a fluid without metal ions can be applied to the surface of the silicon wafer.

  Synthetic resins such as vinyl chloride resin (PVC), ethylene tetrafluoride / perfluoroalkoxy vinyl ether copolymer resin (PFA), or quartz glass are used for the non-metallic lid member and non-metallic covering member. In addition, polyphenylene sulfide resin (PPS) or the like is preferably used for the cylindrical body made of synthetic resin. Further, as the cladding tube, tetrafluoroethylene resin (PTFE), tetrafluoroethylene A fluorine resin such as a fluoroalkoxy vinyl ether copolymer resin (PFA) is preferably used.

  In the present invention, the seal ring interposed between the annular outer end surface of the lid member and the annular end surface of the cylindrical body, and interposed between the cylindrical inner peripheral surface of the covering member and the cylindrical outer peripheral surface of the cladding tube. The sealing ring may be further provided, and when such a sealing ring is provided, a fluid free from metal ions can be more reliably applied to the surface of the silicon wafer.

  In a preferred example, the bearing is interposed between the outer ring fixed to the inner peripheral surface of the hollow member, the inner ring fixed to the outer peripheral surface of the hollow rotary shaft member, and the outer ring and the inner ring, and each row is hollow. A double-row angular contact ball bearing comprising a plurality of rows of steel balls arranged in the rotation direction of the rotary shaft member is provided.

  By supporting the hollow rotary shaft member on the hollow member through the double row angular contact ball bearing so as to be rotatable about the axis, the axial force (thrust force) generated in the hollow rotary shaft member is double row angular contact ball. It can be effectively received by bearings.

  The high-pressure gas supply means has a pressure larger than the pressure of the fluid introduced into the fluid introduction hole, specifically 0.05 MPa or more, preferably 0.1 to 0. 0 than the pressure of the fluid introduced into the fluid introduction hole. The high-pressure gas having a large pressure of 5 MPa is preferably supplied to a cylindrical gap between the cylindrical inner peripheral surface of the hollow member and the cylindrical outer peripheral surface of the hollow rotary shaft member. The fluid introduced into the hollow portion of the hollow member through the fluid introduction hole is composed of pure water, cleaning liquid, nitrogen gas, a mixture of pure water and nitrogen gas, a mixture of cleaning liquid and nitrogen gas, or the like. High pressure fluid can be exemplified, and examples of the gas supplied by the high pressure gas supply means include air, helium gas, nitrogen gas, and argon gas.

  According to the present invention, it is possible to eliminate the generation of abrasion powder at a portion connecting the non-rotating tube and the rotating tube, and to a fluid such as a cleaning fluid such as pure water containing an inert gas that passes through, a slurry fluid such as a polishing fluid. Thus, it is possible to provide a rotary joint that can eliminate the generation of wear powder and can eliminate the generation of metal ions in the fluid, if necessary.

  Next, embodiments of the present invention will be described in more detail based on preferred examples shown in the drawings. The present invention is not limited to these examples.

  1 to 3, the rotary joint 1 of the present example has a hollow portion 2 inside and a hollow member having a fluid introduction hole 5 that communicates the hollow portion 2 with the outside 4 on one end surface 3 side in the axial direction X. 6 and one end 7 which is the opening end of the hollow member 6 on the hollow portion 2 side of the fluid introduction hole 5, and has one opening end 9 in the axial direction X facing the gap 8 in the axial direction X and the hollow member A hollow rotating shaft member 12 having a projecting end portion 11 projecting from the other end surface 10 of the axial direction X to the outside 4 and mounted in the hollow portion 2 of the hollow member 6, and hollow in the hollow portion 2 of the hollow member 6. A contact-type bearing 13 that is interposed between the member 6 and the hollow rotary shaft member 12 and is rotatable in the R direction around the axis O with respect to the hollow member 6; Between one open end 9 of the hollow rotary shaft member 12 and the bearing 13 at X High-pressure gas supply means for supplying high-pressure gas to a cylindrical gap 16 between the cylindrical inner peripheral surface 14 of the hollow member 6 defining the hollow portion 2 positioned and the cylindrical outer peripheral surface 15 of the hollow rotary shaft member 12. 17, a high-pressure gas discharge means 18 that is arranged between the high-pressure gas supply means 17 and the bearing 13 in the axial direction X and discharges the high-pressure gas supplied to the cylindrical gap 16 to the outside 4, And cooling means 19 for cooling the vicinity.

  The hollow member 6 includes a fluid introduction hole 5, an inner end face 21 in the axial direction X at which one end 7, which is the open end of the fluid introduction hole 5 on the hollow portion 2 side, and a cylindrical inner peripheral face 22 connected to the inner end face 21. A non-metallic lid member 24 having an annular outer end surface 23 in the axial direction X connected to the inner peripheral surface 22, one annular end surface 26 contacting the annular outer end surface 23 in the axial direction X of the lid member 24, and a lid An inner synthetic resin cylindrical body 29 having a cylindrical inner peripheral surface 27 having a smaller diameter than the inner peripheral surface 22 of the member 24 and a cylindrical outer peripheral surface 28 having a larger diameter than the inner peripheral surface 22 of the lid member 24. And an annular end surface 30 in the axial direction X that contacts the annular outer end surface 23 in the axial direction X of the lid member 24, a cylindrical inner peripheral surface 31 that contacts the outer peripheral surface 28 of the cylindrical body 29, and an inner peripheral surface 31. A cylindrical inner peripheral surface 32 having a small diameter, a cylindrical outer peripheral surface 33 connected to one annular end surface 30, and An outer aluminum cylindrical body 35 having a cylindrical outer peripheral surface 34 smaller in diameter than the peripheral surface 33 and one annular end surface in the axial direction X that contacts the other annular end surface 36 in the axial direction X of the cylindrical body 29. 37, an annular spacer member 40 having a cylindrical inner peripheral surface 38 having a larger diameter than the inner peripheral surface 27 of the cylindrical body 29 and an outer peripheral surface 39 in contact with the inner peripheral surface 31 of the cylindrical body 35; An annular plate 43 having one annular end surface 42 in the axial direction X that contacts the other annular end surface 41 of the 35, an inner peripheral surface 44 that contacts the outer peripheral surface 34 of the cylindrical body 35, and an outer peripheral surface 33 of the cylindrical body 35. And an annular member 46 having a flush outer peripheral surface 45.

  For the non-metallic lid member 24, a synthetic resin such as vinyl chloride resin (PVC), ethylene tetrafluoride / perfluoroalkoxy vinyl ether copolymer resin (PFA), or quartz glass is preferably used. For the resin cylindrical body 29, polyphenylene sulfide resin (PPS) or the like is preferably used.

  The cylindrical inner peripheral surface 14 of the hollow member 6 that defines the hollow portion 2 in cooperation with the inner end surface 21 and the annular end surface 42 is the cylindrical inner peripheral surface 22 of the lid member 24 and the cylindrical shape of the cylindrical body 29. The inner peripheral surface 27 of the cylindrical member 35, the cylindrical inner peripheral surface 32 of the cylindrical body 35, and the cylindrical inner peripheral surface 38 of the spacer member 40. The lid member 24 includes a plurality of lid members 24 arranged in the R direction. The annular plate 43 is fixed to the cylindrical body 35 via screw members 52 arranged in the R direction.

  The hollow rotary shaft member 12 includes an annular one end surface 54 in the axial direction X, a small-diameter cylindrical outer peripheral surface 55 connected to the one end surface 54, and a larger diameter than the outer peripheral surface 55, and the inner peripheral surface of the cylindrical body 29. 27 has a cylindrical outer peripheral surface 57 that forms an annular gap 56 having a narrow width in the radial direction, and a through hole 59 that extends from one end surface 54 in the axial direction X to the other annular end surface 58 in the axial direction X. In addition, the annular plate 43 serving as the other end surface 10 in the axial direction X of the hollow member 6 has a projecting end portion 61 projecting from the other annular end surface 60 in the axial direction X to the outside 4 and a smaller diameter than the outer peripheral surface 57 and a spacer member. A hollow rotary shaft member having an outer peripheral surface 63 that forms an annular space 62 with the inner peripheral surface 40 of 40 and a cylindrical outer peripheral surface 66 that is smaller in diameter than the outer peripheral surface 63 and has a threaded portion 65 formed therein. On the outer peripheral surface 55 of the small diameter of the main body 67 and the hollow rotary shaft member main body 67 The cylindrical inner peripheral surface 71 fitted to the small-diameter outer peripheral surface 55 is touched and has a larger diameter than the inner peripheral surface 71 and narrower in the radial direction between the inner peripheral surface 27 of the cylindrical body 29 A cylindrical outer peripheral surface 74 that forms a wide annular clearance 73 in the radial direction between the annular clearance 72 and the inner peripheral surface 22 of the lid member 24, and a hollow portion of the fluid introduction hole 5 of the lid member 24. The one end 7 on the second side has one open end 9 in the axial direction X facing the gap 8 and communicates from the one open end 9 to the through hole 59 of the hollow rotary shaft member main body 67 in the axial direction X. A non-metallic covering member 77 having an outer annular end surface 76 facing the through hole 75 and the inner end surface 21 and having the open end 9 positioned therein, and the covering member 77 and the hollow rotating shaft member main body 67 are inserted into both through holes 59 and 75 and both through holes 59 and 75 5 is provided with a hollow rotary shaft member body 67 and the outer peripheral surface 79 made of a synthetic resin cladding 80 having a in contact with the cylindrical inner peripheral surface 78 of the cover member 77 which defines the.

  For the non-metallic covering member 77, a synthetic resin such as vinyl chloride resin (PVC), ethylene tetrafluoride / perfluoroalkoxy vinyl ether copolymer resin (PFA), or quartz glass is preferably used. For the manufactured cladding tube 80, a fluorine resin such as tetrafluoroethylene resin (PTFE) or tetrafluoroethylene / perfluoroalkoxy vinyl ether copolymer resin (PFA) is preferably used.

  The cylindrical outer peripheral surface 15 of the hollow rotary shaft member 12 is composed of cylindrical outer peripheral surfaces 57, 63 and 66 of the hollow rotary shaft member main body 67 and a cylindrical outer peripheral surface 74 of the covering member 77.

  An annular end 85 in the axial direction X of the narrow annular gap 56 formed by the inner peripheral surface 27 of the cylindrical body 29 and the outer peripheral surface 57 of the hollow rotary shaft member main body 67 is the inner peripheral surface of the cylindrical body 29. 27 and the outer peripheral surface 74 of the covering member 77, which is adjacent to the annular one end 86 in the axial direction X of the narrow annular gap 72, and covers the inner peripheral surface 27 of the cylindrical body 29. The other annular end 87 in the axial direction X of the narrow annular gap 72 formed by the outer peripheral surface 74 of the member 77 is formed by the inner peripheral surface 22 of the lid member 24 and the outer peripheral surface 74 of the covering member 77. A wide annular gap 73 is formed adjacent to the annular end 88 in the axial direction X, and is formed by the inner peripheral surface 22 of the lid member 24 and the outer peripheral surface 74 of the covering member 77. The other annular end 89 in the axial direction X of the annular gap 73 is formed between the inner end face 21 of the lid member 24 and the through hole of the covering member 77. 5, adjacent to the space 90 between the end surface 76 in the axial direction X of the covering member 77 in which one open end 9 of the cover member 5 is located, and the inner end surface 21 of the lid member 24 and the through hole 75 of the covering member 77. A space 90 between the cover member 77 and the end surface 76 in the axial direction X where the one open end 9 is located is in communication with the fluid introduction hole 5 and the inside of the cladding tube 80, and the inner peripheral surface 27 of the cylindrical body 29. And the other annular end 91 in the axial direction X of the narrow annular gap 56 formed by the outer peripheral surface 57 of the hollow rotary shaft member main body 67 is in communication with the space 62.

  A pressurized fluid, for example, a pressurized fluid made of a mixture of pure water and nitrogen gas is supplied to the fluid introduction hole 5 via a pipe, and the fluid introduction hole 5 is supplied to the fluid introduction hole 5. The fluid is introduced into the space 90 of the hollow portion 2 through the fluid introduction hole 5, and the pressurized fluid introduced into the space 90 is introduced into the cladding tube 80 on the opening end 9 side, and the other end surface 58. On the side from the inside of the cladding tube 80.

  The high-pressure gas supply means 17 for supplying high-pressure gas to the cylindrical gap 16 is formed in the cylindrical body 35 through the cylindrical body 35 in the radial direction and is a pair of through holes 101 and 102 arranged in the axial direction X. And a circular hole formed on the inner peripheral surface 27 of the cylindrical body 29 with the other radial end of each of the through holes 101 and 102 opening to the outside 4 at one end in the radial direction on the outer peripheral surface 33 side. The annular grooves 103 and 104 and the annular grooves 103 and 104 are opened at one end in the radial direction so as to communicate with the grooves 103 and 104 and penetrate the cylindrical body 29 in the radial direction. There are four through holes 105 and 106 formed in the cylindrical body 29 at equal angular intervals of 90 degrees in the R direction around the center O, and each of the through holes 105 and 106 has a radial direction. One end of the corresponding groove 103 and A large-diameter circular hole 107 opened in 104 and a small-diameter aperture that communicates with the corresponding circular hole 107 at one end in the radial direction and opens into the annular gap 56 at the inner peripheral surface 27 at the other end in the radial direction. And a circular hole 108.

  The high-pressure gas supply means 17 is a high-pressure gas supplied to the through holes 101 and 102 through the pipe, and is a pressure larger than the pressure of the fluid introduced into the fluid introduction hole 5, specifically 0.05 MPa or more. The high-pressure gas having a large pressure of preferably 0.1 to 0.5 MPa is led to the grooves 103 and 104, and the high-pressure gas led to the grooves 103 and 104 is led to each throttle hole 108 through each circular hole 107. In addition, it is ejected from the other end of each throttle hole 108 into the annular gap 56 and supplied to the annular gap 56.

  The high-pressure gas discharge means 18 includes a space 62 that communicates with the other end 91 of the annular gap 56 and the spacer member 40 in the radial direction, with the central axis O as the center, and the spacer at an equal angular interval of 180 degrees in the R direction. Two through holes 111 and 112 that are formed in the member 40 and open to the space 62 at one end in the radial direction and communicate with the space 62, and the other radial ends of the through holes 111 and 112 are open. The annular groove 114 is formed in the outer peripheral surface 39 of the spacer member 40 and communicates with each of the through holes 111 and 112, and the annular groove 114 opens at one end in the radial direction. 114, communicates with the cylindrical body 35 in the radial direction, and has a through hole 115 formed in the cylindrical body 35 that opens to the outside 4 at the other radial end on the outer peripheral surface 33 side.

  The high-pressure gas discharge means 18 is a high-pressure gas from the high-pressure gas supply means 17 and the high-pressure gas from the other end 91 of the annular gap 56 through the space 62, the through holes 111 and 112, the grooves 114 and the through holes 115. It discharges to the outside 4.

  The bearing 13 includes an outer ring 121 sandwiched between the spacer member 40 and the annular plate 43 in the axial direction X and fixed to the inner peripheral surface 32 on the inner peripheral surface 14 of the hollow member 6, and the outer peripheral surface 15 of the hollow rotary shaft member 12. And the inner ring 122 fixed to the outer peripheral surface 66, and a plurality of two rows arranged between the outer ring 121 and the inner ring 122 and arranged in the R direction that is the rotational direction of the hollow rotary shaft member 12. A double row angular contact ball bearing 124 having a steel ball 123 is provided, and the inner ring 122 is prevented from dropping from the hollow rotary shaft member main body 67 by a nut 126 screwed to the washer 125 and the threaded portion 65. It is fixed to.

  The hollow rotary shaft member 12 having the cladding tube 80 is supported by the hollow member 6 so as to be rotatable in the R direction via a bearing 13 including a double row angular ball bearing 124 which is a radial and thrust bearing.

  The cooling means 19 has an annular groove 131 formed on the outer peripheral surface 34 of the cylindrical body 35 and opens to the outside 4 at one end in the radial direction on the outer peripheral surface 45 side, while the radial direction on the inner peripheral surface 44 side. The through-hole 132 for introducing cooling water formed in the annular member 46 by opening in the groove 131 at the other end of the inner surface, and the outer peripheral surface 45 side opening to the outside 4 at the one end in the radial direction, while the inner peripheral surface A through hole for cooling water discharge is formed in the annular member 46 at the other end in the radial direction on the 44 side and formed in the annular member 46 at an angular interval of 180 degrees in the R direction with respect to the through hole 132 in the R direction. Hole 133.

  The cooling means 19 includes a bearing 13 composed of a double row angular ball bearing 124 via a cylindrical body 35 with cooling water supplied to the groove 131 via the through hole 132 and discharged from the groove 132 via the through hole 133. It is designed to cool.

  The rotary joint 1 is interposed between the annular outer end face 23 of the lid member 24 and the annular end face 26 of the cylindrical body 29 with respect to leakage of fluid from the fluid introduction hole 5 and high-pressure gas from the through holes 101 and 102. The seal ring 141, the seal ring 142 interposed between the cylindrical inner peripheral surface 78 of the covering member 77 and the cylindrical outer peripheral surface 79 of the cladding tube 80, the outer peripheral surface 28 of the cylindrical body 29, and the cylindrical body 35, the two seal rings 143 that are interposed between the inner peripheral surface 31 and the through holes 101 and 102 in the axial direction X, the annular end surface 36 of the cylindrical body 29, and the spacer member 40. A seal ring 144 interposed between the annular end surface 37 and an outer peripheral surface 34 of the cylindrical body 35 and an inner peripheral surface 44 of the annular member 46 against leakage of cooling water from the through hole 132. Between And further comprising a two seal rings 145 disposed across the grooves 131 and through holes 132 and 133 in the axial direction X with being Zaisa.

  In the rotary joint 1 described above, the fluid introduction hole 5 includes, for example, a through hole 101 and a supply source that supplies, for example, a cleaning liquid as a pressurized fluid in a surface cleaning apparatus that cleans the surface of a silicon wafer. Reference numeral 102 denotes a high-pressure gas generating source that generates a purified high-pressure gas via a pipe, and the through-hole 132 passes through a pipe to a cooling water supply source that supplies cooling water, and the axis O is the center. The hollow rotary shaft member 12 configured to rotate in the R direction is connected to the rotary tube on the other end face 58 side, and the fluid supplied to the fluid introduction hole 5 The fluid introduced into the cladding tube 80 through the gap 8 and the opening end 9 is supplied as a cleaning liquid for cleaning the surface of the silicon wafer by being supplied to the rotating tube from the other end surface 58 side. The high-pressure gas used and supplied to the through holes 101 and 102 is ejected from the throttle hole 108 to the annular gap 56 through the grooves 103 and 104 and the circular hole 107 to form a high-pressure gas layer in the annular gap 56. The hollow rotary shaft member 12 supported by the bearing 13 so as to be rotatable in the R direction is supported so as to be rotatable in a non-contact manner in the R direction even with such a high pressure gas layer, and the high pressure gas layer is provided in the annular gap 56. The formed high-pressure gas is discharged to the outside 4 through the space 62, the through holes 111 and 112, the groove 114 and the through hole 115.

  The high pressure gas ejected into the annular gap 56 partially enters the inside of the cladding tube 80 via the annular gap 73 and the space 90 due to the pressure difference between the high pressure gas and the fluid supplied from the fluid introduction hole 5. Although it may be introduced, since it is sufficiently cleaned, some of the high-pressure gas can be introduced from the fluid introduction hole 5 without contaminating the fluid supplied from the fluid introduction hole 5. It is supplied to the surface of the silicon wafer together with the supplied fluid.

  By the way, according to the rotary joint 1, one open end 9 of the hollow rotary shaft member 12 and one end 7 on the hollow portion 2 side of the fluid introduction hole 5 of the hollow member 6 face each other with a gap 8. In addition, the generation of friction powder due to the frictional contact at the upper end of the hollow rotary shaft member 12 and the bearing 13 between the high-pressure gas supply means 17 and the annular gap 56 can be eliminated. Since the high-pressure gas supplied and supplied to the annular gap 56 is discharged to the outside 4 via the high-pressure gas discharge means 18, the bearing 13 and the hollow rotary shaft are filled with the high-pressure gas supplied to the annular gap 56. Friction powder generated in the contact-type bearing 13 can be isolated from one open end 9 of the member 12 and fluid introduced into the gap 8 from the fluid introduction hole 5 and into the cladding tube 80 from the gap 8. Can be prevented.

  Further, since each of the lid member 24 and the covering member 77 is made of a non-metal, and each of the cylindrical body 29 and the cladding tube 80 is made of a synthetic resin, generation of metal ions in a fluid and a high-pressure gas that are in contact with them. Thus, a fluid free of metal ions and possibly high pressure gas can be supplied to the surface of the silicon wafer.

  Further, according to the rotary joint 1, since the hollow rotary shaft member 12 is supported by the hollow member 6 so as to be rotatable in the R direction via the double row angular ball bearing 124, the axial direction generated in the hollow rotary shaft member 12. X force (thrust force) can be effectively received by the double-row angular contact ball bearing 124.

  The conventional rotary joint, the lid member 24 and the cover member 77 are each made of polyvinyl chloride resin (PVC), the cylindrical body 29 is made of polyphenylene sulfide resin (PPC), and the cladding tube 80 is made of tetrafluoroethylene resin (PFC). The rotary joint 1 of this example formed by PTFE) is used for the flow rate controller of the wafer rotation holding device shown in FIG. 5 of JP-A-2001-148414, respectively, and the silicon wafer supported by the wafer rotation holding device is used. The surface was washed to measure metal ions and friction powder (particles), and the measurement results are shown in Tables 1 to 3.

Metal ion measurement conditions Metal ion analyzer: VP-ICP-MS analysis Model: ELAN 6100 DRC No. 2
The rotation speed of the hollow rotating shaft member 12: 900 rpm
Analyzing metal ions when using back blow and back rinse

Wear powder (particle) measurement conditions Particle (wafer surface inspection) Model: WIS-CR81
The number of particles was measured when only back blow and when back blow and back rinse were used.

  As is apparent from a comparison between the above conventional rotary joint and the rotary joint 1 of the present example, according to the present invention, a rotary joint capable of achieving the above object can be provided.

It is a front view of a preferable example of the present invention. It is the II-II line of the example shown in FIG. 1, and the (II)-(II) arrow directional cross-sectional explanatory drawing. FIG. 3 is a cross-sectional explanatory view taken along line III-III shown in FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotary joint 2 Hollow part 3 One end surface 4 External 5 Fluid introduction hole 6 Hollow member 7 One end 8 Crevice 10 Other end surface 11 Projection end part 12 Hollow rotary shaft member 13 Bearing 14 Inner peripheral surface 15 Outer peripheral surface 16 Cylindrical clearance 17 High pressure gas Supply means 18 High-pressure gas discharge means

Claims (6)

A hollow member having a hollow portion therein and having a fluid introduction hole that communicates the hollow portion with the outside on one end surface side in the axial direction, and a gap at the opening end of the hollow portion side of the fluid introduction hole of this hollow member A hollow rotary shaft member having one open end in the axial direction and having a protruding end portion protruding outward from the other end surface in the axial direction of the hollow member and mounted in the hollow portion of the hollow member; A contact-type bearing that is interposed between the hollow member and the hollow rotary shaft member in the hollow portion of the member, and that is rotatable about the shaft center with respect to the hollow member; A cylindrical gap between the cylindrical inner peripheral surface of the hollow member and the cylindrical outer peripheral surface of the hollow rotary shaft member that defines the hollow portion located between one open end of the hollow rotary shaft member and the bearing. High-pressure gas supply means for supplying high-pressure gas, and in the axial direction It has and a high-pressure gas discharge means for discharging high-pressure gas supplied to the cylinder gap to the outside together is arranged between the gas supply means and the bearing, the hollow member, the fluid introduction hole, the fluid introduced From a vinyl chloride resin having an axial inner end face where the opening end of the hollow portion side of the hole is located, a cylindrical inner peripheral face connected to the inner end face, and an axial annular outer end face connected to the inner peripheral face A non-metallic lid member, an annular end surface that contacts the annular outer end surface in the axial direction of the lid member, a cylindrical inner circumferential surface having a smaller diameter than the inner circumferential surface of the lid member, and an inner circumferential surface of the lid member And a cylindrical body made of a synthetic resin made of polyphenylene sulfide resin having a large-diameter cylindrical outer peripheral surface, and the hollow rotary shaft member has a small-diameter outer peripheral surface and a larger diameter than the outer peripheral surface. Narrow annular gap in the radial direction between the inner peripheral surface of the cylinder A hollow rotary shaft having a cylindrical outer peripheral surface forming a through hole extending from one end surface in the axial direction to the other end surface in the axial direction and a projecting end portion protruding outward from the other end surface in the axial direction of the hollow member A member main body, an inner peripheral surface that is in contact with a small-diameter outer peripheral surface of the hollow rotary shaft member main body and is fitted to the small-diameter outer peripheral surface, an inner peripheral surface of the cylindrical body that is larger in diameter than the inner peripheral surface; A cylindrical outer circumferential surface that forms a narrow annular gap in the radial direction between them, and a wide annular gap in the radial direction between the inner circumferential surface of the lid member and the hollow of the fluid introduction hole of the lid member A through hole extending in the axial direction so as to communicate with the through hole of the hollow rotary shaft member body from the one open end. Non-metallic covering member made of vinyl chloride resin, and the covering member and hollow A cover member that is inserted into both through-holes of the rotary shaft member main body and that defines both through-holes and an outer peripheral surface that is in contact with the cylindrical inner peripheral surface of the hollow rotary shaft member main body is made of tetrafluoroethylene resin. And a cylindrical inner peripheral surface of the hollow member that defines the hollow portion includes a cylindrical inner peripheral surface of the lid member and a cylindrical inner peripheral surface of the cylindrical body. The cylindrical outer peripheral surface of the hollow rotary shaft member includes the cylindrical outer peripheral surface of the hollow rotary shaft member main body and the cylindrical outer peripheral surface of the cover member. One end of the annular ring in the axial direction of the narrow annular gap formed with the outer peripheral surface of the rotating shaft member body is a narrow annular formed with the inner peripheral surface of the cylindrical body and the outer peripheral surface of the covering member It communicates adjacent to one end of the annular ring in the axial direction of the gap, and is formed by the inner peripheral surface of the cylindrical body and the outer peripheral surface of the covering member The other end of the annular ring in the axial direction of the annular gap of the width is adjacent to one end of the annular ring in the axial direction of the wide annular gap formed by the inner peripheral surface of the lid member and the outer peripheral surface of the cover member. The other annular end of the wide annular gap formed by the inner peripheral surface of the cover member and the outer peripheral surface of the cover member is in communication with the inner end surface of the cover member and the through hole of the cover member. The high-pressure gas supply means communicates adjacent to the space between the axial end face of the covering member where one opening end is located, and the inner peripheral face of the cylindrical body and the outer peripheral face of the hollow rotary shaft member main body. A high-pressure gas is supplied to the narrow annular gap formed by the shaft of the narrow annular gap formed by the inner peripheral surface of the cylindrical body and the outer peripheral surface of the hollow rotary shaft member body. The other end of the annular ring is in communication with the high pressure gas discharge means, and the inner end face of the lid member and one open end of the through hole of the cover member are positioned. The space between the axial end face of the cover member which is rotary joint in communication with the interior of the fluid inlet hole and cladding. A seal ring interposed between the annular outer end surface of the lid member and the annular end surface of the cylindrical body, and a seal ring interposed between the cylindrical inner peripheral surface of the cover member and the cylindrical outer peripheral surface of the cladding tube The rotary joint according to claim 1, further comprising: The bearing is interposed between the outer ring fixed to the inner peripheral surface of the hollow member, the inner ring fixed to the outer peripheral surface of the hollow rotary shaft member, and the outer ring and the inner ring, and each row of the hollow rotary shaft member 3. The rotary joint according to claim 1, further comprising a double row angular ball bearing including a plurality of rows of steel balls arranged in a rotational direction. The high-pressure gas supply means supplies high-pressure gas having a pressure larger than the pressure of the fluid introduced into the fluid introduction hole between the cylindrical inner peripheral surface of the hollow member and the cylindrical outer peripheral surface of the hollow rotary shaft member. The rotary joint according to any one of claims 1 to 3, wherein the rotary joint is supplied to the cylindrical gap. The high-pressure gas supply means is configured to supply high-pressure gas having a pressure greater than 0.05 MPa than the pressure of the fluid introduced into the fluid introduction hole by using a cylindrical inner peripheral surface of the hollow member and a cylindrical outer periphery of the hollow rotary shaft member. The rotary joint as described in any one of Claim 1 to 3 supplied to the cylindrical clearance gap between surfaces. The pressurized fluid introduced into the hollow portion of the hollow member through the fluid introduction hole is composed of pure water, cleaning liquid, nitrogen gas, a mixture of pure water and nitrogen gas, or a mixture of cleaning liquid and nitrogen gas. The rotary joint as described in any one of Claim 1 to 5.

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