JP6011520B2 - Rotation mechanism, rotation drive device, transport device, and manufacturing device - Google Patents

Description

  The present invention relates to a rotation mechanism, a rotation drive device, a transport device, and a manufacturing device that separate two spaces having different pressures.

  In a manufacturing apparatus such as a transport apparatus, a semiconductor manufacturing apparatus, or a machine tool, a rotation mechanism that rotates a rotary stage or rotates a semiconductor substrate, a workpiece, or a tool is used. As such a rotation mechanism, for example, Patent Document 1 describes a positioning device (see FIG. 2).

JP 2007-9939 A

  The technique described in Patent Document 1 rotates a shaft while isolating a process chamber such as a vacuum chamber from an external environment by accommodating an O-ring that is a contact seal in a seal groove. is there. Although the O-ring enhances the sealing performance, the O-ring is forcibly deformed to come into contact with the shaft, so that the O-ring or the shaft may be deformed or worn. Accordingly, in order to reduce the possibility of deformation or wear of the O-ring or the shaft, a lubricant such as grease is applied to the surface of the O-ring. However, when a lubricant is applied to the surface of the O-ring, the lubricant may be scattered in the process chamber. For this reason, there is a demand for a rotating mechanism that has a lubricant on the surface of the contact seal but has a reduced possibility of the lubricant scattering into the internal space.

  The present invention has been made in view of the above, and provides a rotation mechanism, a rotation drive device, a conveyance device, and a manufacturing device that reduce the possibility that the lubricant supplied to the surface of the contact-type seal is scattered in the internal space. The purpose is to provide.

  In order to achieve the above object, a rotating mechanism according to the present invention is a rotating mechanism that separates two spaces having different pressures, and is provided with a housing, a shaft inserted into the housing, and the housing. A bearing that is rotatably supported, a rotating portion that is provided at one end of the shaft and rotates together with the shaft, and whose radially outer surface faces the housing with a gap of a predetermined size, and the gap A plurality of annular seal members for sealing at different positions, and a lubricant groove for storing a lubricant to be supplied between the annular seal member and a radially outer surface of the rotating portion. At least one of the annular seal members is on the low pressure side of the two spaces having different pressures from the lubricant groove. As a result, the lubricant that has moved from the lubricant groove toward the annular seal member is prevented from moving toward the internal space by the annular seal member. For this reason, the rotating mechanism according to the present invention can reduce the possibility that the lubricant supplied to the surface of the contact-type seal is scattered in the internal space.

  As a desirable aspect of the present invention, the housing includes a seal fixing spacer that defines the size of the gap and fixes the annular seal member, and the radially inner side surface of the seal fixing spacer includes a plurality of the plurality of seal fixing spacers. Preferably, the lubricant groove is provided at a position between the annular seal members, and is provided on a radially inner side surface of the seal fixing spacer. Thereby, the lubricant is easily supplied to the surfaces of the plurality of annular seal members. For this reason, wear of the annular seal member or the rotating portion is suppressed, and the rotating mechanism according to the present invention can reduce the frequency of replacement of components that enhance the sealing performance.

  As a desirable mode of the present invention, the lubricant groove is provided in a part of the radially inner side surface of the seal fixing spacer, and the lubricant groove is located on the radially inner side surface of the seal fixing spacer more than the lubricant groove. The distance between the annular seal member side portion and the radially outer surface of the rotating portion is preferably smaller than the size of the gap. Thereby, the lubricant gradually passes through the gap between the radially inner side surface and the radially outer surface. For this reason, the rotation mechanism can suppress a situation in which a large amount of lubricant is supplied to the annular seal member.

  As a desirable aspect of the present invention, the housing includes a seal fixing spacer that defines the size of the gap and fixes the annular seal member, and the radially inner side surface of the seal fixing spacer includes a plurality of the plurality of seal fixing spacers. Preferably, the lubricant groove is provided in a portion of the radially outer surface of the rotating portion that faces the radially inner side surface of the seal fixing spacer. Thereby, the lubricant is easily supplied to the surfaces of the plurality of annular seal members. For this reason, wear of the annular seal member or the rotating portion is suppressed, and the rotating mechanism according to the present invention can reduce the frequency of replacement of components that enhance the sealing performance.

  As a desirable aspect of the present invention, the lubricant groove is provided in a part of a radially outer surface of the rotating portion facing a radially inner side surface of the seal fixing spacer, and the diameter of the rotating portion is Of the outer surface in the direction, it is preferable that the distance between the portion closer to the annular seal member than the lubricant groove and the radially inner side surface of the seal fixing spacer is smaller than the size of the gap. Thereby, the lubricant gradually passes through the gap between the radially inner side surface and the radially outer surface. For this reason, the rotation mechanism can suppress a situation in which a large amount of lubricant is supplied to the annular seal member.

  As a desirable mode of the present invention, it is preferable that it is a rotation drive device provided with the rotation mechanism mentioned above and the electric motor which rotates the shaft. With this structure, the rotary drive device can achieve high sealing performance.

  As a desirable aspect of the present invention, it is preferable that the conveyance device includes the rotation mechanism described above and a movable member that moves the object to be conveyed, and the rotation of the shaft and the movable member are interlocked. With this structure, the transfer device can achieve high sealing performance.

  As a desirable mode of the present invention, it is preferred that it is a manufacturing device provided with the rotation mechanism mentioned above. With this structure, the manufacturing apparatus can achieve high sealing performance and can improve the quality of the product.

  According to the present invention, it is possible to provide a rotation mechanism, a rotation drive device, a conveyance device, and a manufacturing device that reduce the possibility that the lubricant supplied to the surface of the contact seal is scattered in the internal space.

FIG. 1 is a cross-sectional view schematically illustrating a manufacturing apparatus including a rotation mechanism according to the first embodiment. FIG. 2 is a cross-sectional view schematically showing the rotation mechanism according to the first embodiment. FIG. 3 is an AA arrow view of FIG. FIG. 4 is an enlarged view of a gap of the rotation mechanism according to the first embodiment. FIG. 5 is an enlarged view of a gap of the rotation mechanism according to the second embodiment.

  Hereinafter, modes for carrying out the present invention (hereinafter referred to as embodiments) will be described with reference to the drawings. In addition, this invention is not limited by the following embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those in a so-called equivalent range. Furthermore, the constituent elements disclosed in the following embodiments can be appropriately combined.

(Embodiment 1)
FIG. 1 is a cross-sectional view schematically illustrating a manufacturing apparatus including a rotation mechanism according to the first embodiment. FIG. 2 is a cross-sectional view schematically showing the rotation mechanism according to the first embodiment. 1 and 2 show a cross section of the rotating mechanism 1 taken along a plane including the rotating center axis Zr of the rotating mechanism 1 and parallel to the rotating center axis Zr. FIG. 3 is an AA arrow view of FIG. FIG. 4 is an enlarged view of a gap of the rotation mechanism according to the first embodiment. The rotation mechanism 1 is a mechanical element that transmits rotation, and is used in a special environment such as a vacuum environment, a reduced pressure environment, or a process gas filling environment. The rotating mechanism 1 is applied to a manufacturing apparatus such as semiconductor manufacturing or machine tool manufacturing, a transport apparatus, and a rotation driving apparatus. Here, as an example, a case where the rotation mechanism 1 is a rotation drive device (spindle unit) provided with a spindle as a rotation shaft in a manufacturing apparatus for semiconductor manufacturing will be described. It is not limited.

  As shown in FIG. 1, for example, a manufacturing apparatus 100 used for semiconductor manufacturing includes a rotation mechanism 1, a housing 10, an electric motor 8, and a control device 91 that controls the electric motor 8. The rotation mechanism 1 and the electric motor 8 transmit the rotation of the electric motor 8 as the rotation driving device 6 to rotate the conveyance table (movable member) 33. The manufacturing apparatus 100 sets the internal space V of the housing 10 to a vacuum environment, a reduced pressure environment, and a process gas filling environment, and then transfers a transfer object (for example, a semiconductor substrate, a workpiece, or a tool) in the internal space V to a transfer table. It is mounted on (movable member) 33 and moved. When the object to be transported is moved, if the electric motor 8 is installed in the internal space V, foreign matter may be generated by the operation of the electric motor 8. Therefore, the manufacturing apparatus 100 installs the electric motor 8 in the external space E while leaving the transfer table 33 in the internal space V. The rotating mechanism 1 transmits the power of the electric motor 8 installed in the external space E to the internal space V while improving the sealing performance by separating the internal space V and the external space E. The electric motor 8 is, for example, a direct drive motor, a drive device using a belt drive, a linear motor, a servo motor, or the like. The control unit 91 includes an input circuit, a central processing unit (CPU) that is a central processing unit, a memory that is a storage device, and an output circuit. According to the program stored in the memory 92, the electric motor 8 is controlled, and the object to be transported (for example, a semiconductor substrate, a workpiece or a tool) in the internal space V is mounted on the transport table (movable member) 33 and moved. The manufacturing apparatus 100 can manufacture a desired product.

  The rotation mechanism 1 includes a housing 2, a rotation member 3, and a bearing 4. The housing 2 is a member that accommodates the bearing 4. In the first embodiment, the housing 2 includes, as a housing body, a barrel portion 21 that is a cylindrical member, and a housing flange portion 22 provided at one end portion of the barrel portion 21. The housing 2 includes a lid portion 23 fixed to the housing flange portion 22 with bolts 27, an outer ring stopper member 24, a seal fixing spacer 25, and a seal fixing spacer, which are arranged inside the body portion 21 of the housing body. 28 is further provided. In the first embodiment, the body portion 21 is a cylindrical member (for example, a cylinder) and has a through hole from one end to the other end. The rotation mechanism 1 is disposed such that the through hole is along the vertical direction and the internal space V side of the through hole is on the upper side in the vertical direction. For this reason, the upper side in FIGS. 1 and 2 is the upper side in the vertical direction, and the lower side in FIGS. 1 and 2 is the lower side in the vertical direction.

  Each of the housing flange portions 22 is a plate-shaped flange member. In the first embodiment, the shape of the housing flange portion 22 is circular in plan view, but these shapes are not limited to circular. The housing flange portion 22 includes the above-described through-hole including the rotation center axis Zr of the shaft 31 and penetrating in the thickness direction. In the housing 2, the housing flange portion 22 is applied from the outside of the housing 10 so as to cover the opening 10 e of the housing 10, and the housing flange portion 22 and the wall surface of the housing 10 are fastened with bolts (not shown). It is fixed to the housing 10. Thereby, the housing 2 can block the opening 10 e of the housing 10 from the outside of the housing 10. The housing flange portion 22 has an annular groove in a portion overlapping the housing 10 in plan view, and an O-ring (annular seal) 11 is fitted into the annular groove to improve the sealing performance between the housing flange portion 22 and the housing 10. ing.

  The rotating member 3 includes a shaft 31, a rotating unit 32, and a transfer table (movable member) 33. The shaft 31 is an output shaft (main shaft) of the rotation mechanism 1, and one end thereof is inserted into the housing 2. The other end of the shaft 31 is connected to the output shaft 81 of the electric motor 8 through a coupling 82. The transfer table (movable member) 33 is fixed to one end portion of the shaft 31 via the rotating portion 32.

  The transport table 33 and the rotating unit 32 rotate together with the shaft 31. In the transfer table 33, an object is placed on the surface opposite to one end of the shaft 31. In the first embodiment, the transport table 33 is a plate-like member and is circular in plan view. The conveyance table 33 projects to the outside in the radial direction of the rotating portion 32 that protrudes in the axial direction from the housing flange portion 22 of the housing 2.

  The bearing 4 is installed inside the housing 2, in the first embodiment, and rotatably supports the shaft 31. The bearing 4 includes a bearing 41 and a bearing 42, and is disposed at a distance along the rotation axis Zr via a double cylindrical bearing spacer 43. Thereby, the bearing 4 can suppress the whirling of the shaft 31 by supporting the shaft 31 at a plurality of locations of the bearing 41 and the bearing 42. In the first embodiment, the shaft 31 is supported by the housing 2 by the two bearings 41 and 42, but the number of bearings is not limited to two.

  As shown in FIG. 2, the bearings 41 and 42 include outer rings 41a and 42a, rolling elements 41b and 42b, and inner rings 41c and 42c. The inner rings 41c and 42c are disposed on the radially inner side of the outer rings 41a and 42a. Thus, in Embodiment 1, the bearings 41 and 42 are both rolling bearings. The rolling elements 41b and 42b are disposed between the outer rings 41a and 42a and the inner rings 41c and 42c. In the bearings 41 and 42, the outer rings 41 a and 42 a are in contact with the inner wall 21 c of the through hole of the body portion 21 of the housing 2.

  One end of the outer ring 41a in the axial direction is in contact with the positioning portion 21a in which the through hole of the body portion 21 is engraved. The outer ring pressing portion 24a of the outer ring stopper member 24 positions and fixes one end of the outer ring 42a in the axial direction. For this reason, the positioning part 21a and the outer ring stopper member 24 sandwich and fix the bearing 41, the bearing spacer 43, and the bearing 42 in the axial direction. With such a structure, the bearings 41 and 42 are attached to the housing 2. In the first embodiment, both the bearings 41 and 42 are ball bearings, but the types of the bearings 41 and 42 as rolling bearings are not limited to ball bearings. In the first embodiment, the bearings 41 and 42 are both rolling bearings, but may be sliding bearings.

  The rotating part 32 has a cylindrical shape, and the radially outer surface faces the housing 2 with a gap 55 having a predetermined size. The rotating part 32 of the first embodiment is coaxial with the shaft 31, but the rotating part 32 protrudes larger in diameter than the shaft 31. For this reason, the rotation part 32 can contact | abut the end surface 32a on the opposite side of the conveyance table 33 to the inner ring | wheel 42c, and can be used as an inner ring | wheel presser. With this structure, the number of parts can be reduced, and an inexpensive rotation mechanism 1 can be provided. One end of the inner ring 41c in the axial direction is in contact with the positioning portion 31a of the outer peripheral recess of the shaft 31. Since the rotating part 32 positions and fixes one end of the inner ring 42c in the axial direction, the positioning part 31a and the rotating part 32 sandwich and fix the bearing 41, the bearing spacer 43 and the bearing 42 in the axial direction. With such a structure, the bearings 41 and 42 are attached to the shaft 31. In addition, although the rotation part 32 of Embodiment 1 is integral with the shaft 31, and is a part of one end of the shaft 31, it is not restricted to this aspect, The rotation part 32 of Embodiment 1 is a separate body from the shaft 31. A member that is coaxially fixed to one end of the shaft 31 and rotates in conjunction with the rotation of the shaft 31 may be used.

  The rotation mechanism 1 includes two annular seal members 5A and 5B that seal the gap 55 at different positions in the direction along the rotation center axis Zr. In the first embodiment, the two annular seal members 5A and 5B are the same, although the positions where they are arranged are different from each other. The number of annular seal members may be plural, and may be three or more.

  The seal fixing spacer 25 defines the size of the gap 55 and fixes the annular seal member 5A. As shown in FIG. 3, the seal fixing spacer 25 is an annular member. As shown in FIG. 2, the seal fixing spacer 25 includes a spacer positioning portion 25 a, a seal fixing concave portion 25 b, a radial inner peripheral portion 25 c, and a radial outer periphery. A portion 25d and an annular convex portion 25e projecting toward the rotating portion 32 rather than the radially inner peripheral portion 25c are provided. At least a part of the radially outer peripheral portion 25 d is in contact with the inner wall 21 b of the through hole of the trunk portion 21. Since the seal fixing spacer 25 acts as a guide for the annular seal member 5A, the contact pressure with which the annular seal member 5A comes into contact with the rotating portion 32 can be set to an appropriate set value.

  The seal fixing spacer 28 is an annular member, defines the size of the gap 55, and fixes the annular seal member 5B. As shown in FIG. 2, the seal fixing spacer 28 includes a seal fixing recess 28b, a radially inner peripheral portion 28c, and a radially outer peripheral portion 28d. At least a part of the radially outer peripheral portion 28 d is in contact with the inner wall 21 b of the through hole of the trunk portion 21. Since the seal fixing spacer 28 acts as a guide for the annular seal member 5B, the contact pressure with which the annular seal member 5B comes into contact with the rotating portion 32 can be set to an appropriate set value.

  The housing flange portion 22 is formed with an annular groove 22a concentrically with the rotation center axis Zr, and at least a part of the radially outer peripheral portion 25d is a part of the wall surface of the annular groove 22a. When the lid portion 23 is fixed to the housing flange portion 22 with bolts 27, the O-ring 26 fitted in the annular groove 22a enhances the sealing performance and seals. The O-ring 26 is disposed at a position having a larger diameter than the annular seal members 5A and 5B. The spacer positioning portion 25 a is sandwiched and fixed between the radial outer peripheral portion 28 d of the seal fixing spacer 28 and the inner wall 21 b of the through hole of the trunk portion 21. The annular groove 22a and the O-ring 26 do not need to be provided when the degree of vacuum in the internal space V is low.

  As shown in FIG. 3, the annular seal member 5 </ b> A is concentric with a rotation center axis Zr as in the case of the rotating portion 32, the seal fixing spacer 25, and the O ring 26 and O ring 11 fixed to the housing flange portion 22. It is arranged to draw. Similarly to the annular seal member 5A, the annular seal member 5B is also arranged so as to draw a concentric circle about the rotation center axis Zr. As shown in FIG. 2, the annular seal members 5 </ b> A and 5 </ b> B are disposed closer to the internal space V on the low pressure side among the two spaces having pressures different from those of the bearing 4. With this structure, the annular seal members 5A and 5B prevent the lubricant used in the bearing 4 from scattering to the internal space V side.

  As shown in FIG. 4, the annular seal member 5 </ b> A includes a fixing portion 52 that contacts the radially inner peripheral portion 25 c of the seal fixing spacer 25 of the housing 2, a lip portion 51 that contacts the radially outer surface 32 p of the rotating portion 32, and An annular connecting portion 53 that connects the fixing portion 52 and the lip portion 51 and a seal flange portion 54 are provided. With this structure, the fixed portion 52, the annular connecting portion 53, and the lip portion 51 have a substantially U-shaped cross section, and the space surrounded by the fixed portion 52, the annular connecting portion 53, and the lip portion 51 has different pressures. Of the two spaces, it opens toward the external space E on the high pressure side. The material of the annular seal member 5A is more preferably polyethylene or polytetrafluoroethylene. Polyethylene or polytetrafluoroethylene is excellent in wear resistance and chemical resistance as a material of the annular seal member 5A, and is suitable for lubrication with the rotating portion 32. As the material of the rotating portion 32 that comes into contact, any one of high carbon chrome bearing steel, martensitic stainless steel, precipitation hardening stainless steel, and precipitation hardening stainless steel high silicon alloy containing 3.4 mass% or more of Si is used. preferable. Since the annular seal member 5A and the annular seal member 5B are the same, the description of each configuration of the annular seal member 5B is omitted.

  As shown in FIG. 4, when the lid portion 23 is fixed to the housing flange portion 22 with bolts 27, the seal fixing spacer 25 sandwiches and fixes the seal flange portion 54 inserted into the seal fixing recess 25b. Thereby, the rotation mechanism 1 of Embodiment 1 can suppress the possibility that the annular seal member 5 </ b> A rotates together with the rotation of the rotating portion 32 by providing the annular seal member 5 </ b> A with the seal flange portion 54.

  As shown in FIG. 4, when the lid portion 23 is fixed to the housing flange portion 22 with bolts 27, the seal fixing spacer 28 sandwiches and fixes the seal flange portion 54 inserted into the seal fixing recess 28b. Thereby, the rotation mechanism 1 of Embodiment 1 can suppress the possibility that the annular seal member 5B rotates together with the rotation of the rotation unit 32 by the annular seal member 5B including the seal flange portion 54.

  Since the rotating part 32 rotates in a state where the annular seal members 5A and 5B are fixed to the housing 2, friction occurs between the annular seal members 5A and 5B and the rotating part 32. The heat generated by the friction may promote the wear of the annular seal members 5A, 5B or the rotating part 32. For this reason, it is desirable that the friction be reduced. Therefore, the rotating mechanism 1 includes a lubricant groove 25l that stores the lubricant Lu supplied between the annular seal member 5 and the radially outer surface 32p of the rotating portion 32.

  The seal fixing spacer 25 includes a radially inner side surface 25f that faces the radially outer surface 32p of the rotating portion 32 at a position between the annular seal members 5A and 5B. The radially inner side surface 25f is on the upper side in the vertical direction from the position of the annular seal member 5B. The lubricant groove 25l is a recess provided in the radially inner side surface 25f of the seal fixing spacer 25. As shown by a broken line in FIG. 3, the lubricant groove 25l is formed in an annular shape. The lubricant Lu stored in the lubricant groove 25l is, for example, grease. For example, a part of the lubricant Lu protrudes from the lubricant groove 25l and is in contact with the radially outer surface 32p by surface tension. Thereby, the lubricant Lu is held by the lubricant groove 25l and the radially outer surface 32p. Further, since the lubricant Lu has fluidity, it is stably supplied from the lubricant groove 25l between the annular seal member 5B and the radially outer surface 32p of the rotating portion 32 by gravity. Thereby, it becomes easy to maintain the state where the lubricant Lu exists between the radially outer surface 32p of the rotating portion 32 and the annular seal member 5B. Further, the lubricant Lu is supplied to the annular seal member 5A by pressure due to slight air leakage between the rotating portion 32 and the annular seal member 5B. The lubricant Lu is also supplied to the annular seal member 5A even when the pressure in the internal space V varies (when the operation of the manufacturing apparatus 100 is started and stopped). Therefore, the wear of the annular seal members 5A, 5B or the rotating portion 32 is suppressed, and in the first embodiment, the rotating mechanism 1 can reduce the replacement frequency of components that improve the sealing performance.

  Of the annular seal members 5A and 5B, the annular seal member 5A is on the lower pressure side than the lubricant groove 25l. As a result, the lubricant Lu that has moved from the lubricant groove 25l toward the annular seal member 5A is prevented from moving toward the internal space V by the annular seal member 5A. For this reason, the rotation mechanism 1 can reduce the possibility that the lubricant Lu supplied to the surface of the contact-type seal scatters into the internal space V.

  Further, the surfaces of the annular seal members 5A and 5B and the rotating portion 32 have a certain degree of surface roughness that is fine irregularities. For this reason, the sealing performance in the portion where the annular seal members 5A, 5B and the rotating portion 32 are in contact may depend on the degree of surface roughness. In the first embodiment, since the lubricant Lu is supplied to the surfaces of the annular seal members 5A and 5B and the rotating portion 32, the lubricant Lu is filled in the recesses of the surface roughness. Therefore, the rotation mechanism 1 can improve the surface roughness of the annular seal members 5A and 5B and the rotation part 32 by the lubricant Lu, and improve the sealing performance.

  The lid portion 23 can adjust the degree of vacuum by appropriately setting the distance Δd1 of the gap s1 between the radially inner side surface 23f and the radially outer surface 32p. The distance Δd1 is preferably 0.001 mm or more and 0.5 mm or less, for example.

  As shown in FIG. 4, the lubricant groove 25l is provided in a part of the radially inner side surface 25f. The seal fixing spacer 25 adjusts the degree of vacuum by appropriately setting a distance Δd2 of a gap s2 between a portion of the radially inner side surface 25f closer to the annular seal member 5A than the lubricant groove 251 and the radially outer surface 32p. be able to. In addition, the seal fixing spacer 25 appropriately sets a distance Δd2 of a gap s3 between a portion of the radially inner side surface 25f closer to the annular seal member 5B than the lubricant groove 251 and the radially outer surface 32p, thereby increasing the degree of vacuum. Can be adjusted. The distance Δd2 is preferably 0.001 mm or more and 0.5 mm or less, for example. Further, the distance Δd2 is smaller than the size of the gap 55. Thereby, the lubricant Lu gradually passes through the gaps s2 and s3 between the radially inner side surface 25f and the radially outer surface 32p. For this reason, the situation where a large amount of the lubricant Lu is supplied to the annular seal members 5A and 5B side is suppressed. In the first embodiment, the gap s2 and the gap s3 are gaps having the same distance Δd2, but may be gaps having different distances.

  As shown in FIG. 4, an urging member 56 is disposed inside the space surrounded by the fixed portion 52, the annular coupling portion 53, and the lip portion 51, and urges the pressing force of the lip portion 51 toward the rotating portion 32. be able to. The urging member 56 is, for example, stainless steel, and is an elastic body that has a V-shaped cross-sectional view in which the flat plate-like portion 56a and the plate-like portion 56b are bent at the bent portion 56c. The urging member 56 is urged so that the tips of the plate-like portion 56a and the plate-like portion 56b spread.

  In the annular seal members 5 </ b> A and 5 </ b> B, in addition to the pressure due to the elastic deformation of the lip portion 51, the lip portion 51 that has received the pressure applied to the urging member 56 contacts the radially outer surface 32 p of the rotating portion 32. For this reason, the rotation mechanism 1 can increase the contact pressure at which the lip portion 51 contacts the radially outer surface 32 p of the rotation portion 32. Furthermore, since the space surrounded by the fixing portion 52, the annular coupling portion 53, and the lip portion 51 is open toward the external space E on the high pressure side, the two spaces having different pressures. This pressure difference can increase the contact pressure at which the lip portion 51 contacts the radially outer surface 32p of the rotating portion 32. Thereby, even if the rotation mechanism 1 makes the vacuum of the internal space V high, it can maintain high sealing performance. Further, not only the inner peripheral side tip 51a of the lip part 51 contacts the radial outer surface 32p, but also at least a part of the inner peripheral side base part 51d of the lip part 51 close to the annular connecting part 53 also has the radial outer surface 32p. To touch. As a result, since the inner peripheral side of the lip portion 51 is in contact with the radially outer surface 32p by the surface, the sealing performance can be maintained.

  Even if the lip portion 51 or the shaft 31 is worn or deformed, the biasing member 56 acts to maintain the contact pressure. For this reason, the rotation mechanism 1 can reduce the replacement frequency of the annular seal members 5 </ b> A and 5 </ b> B or the rotating portion 32 that are components that enhance the sealing performance.

  A space surrounded by the lip portion 51, the annular connecting portion 53, and the fixed portion 52 is open to the high-pressure side external space E among the two internal spaces V and external spaces E having different pressures. With this structure, the pressure due to the elastic deformation of the lip portion 51 itself of the annular seal members 5A and 5B and the pressure applied by the urging member 56 are synergistic, and the annular seal members 5A and 5B come into contact with the rotating portion 32. Contact pressure can be increased.

  The urging member 56 is preferably provided in a space surrounded by the fixing portion 52, the annular coupling portion 53, and the lip portion 51. With this structure, the lip portion 51 can be in surface contact with the rotating portion 32 easily.

  In the first embodiment, the rotation mechanism 1 is arranged so that the through hole of the body portion 21 is along the vertical direction, but may be arranged so that the through hole is along the horizontal direction. In such an arrangement, there is a place where the lubricant groove 25l is positioned above the rotating portion 32 in the vertical direction, and therefore the lubricant Lu is supplied to the radially outer surface 32p of the rotating portion 32 by gravity. The lubricant Lu is supplied between the annular seal members 5 </ b> A and 5 </ b> B and the rotating portion 32 through the radially outer surface 32 p.

  As described above, the rotation mechanism 1 can separate the two internal spaces V and the external space E having different pressures. The rotation mechanism 1 includes a housing 2, a shaft 31 inserted into the housing 2, a bearing 4 that is provided in the housing 2 and rotatably supports the shaft 31, is provided at one end of the shaft 31, and rotates together with the shaft 31. In addition, the radially outer surface 32p includes the seal fixing spacer 25 of the housing 2 and the rotating portion 32 that faces the gap 2 having a predetermined size. The rotating mechanism 1 also includes a plurality of annular seal members 5A and 5B that seal the gap 55 at different positions, and a lubricant Lu that is supplied between the annular seal members 5A and 5B and the radially outer surface 32p of the rotating portion 32. And a lubricant groove 25l for storing. At least one annular seal member 5A among the plurality of annular seal members 5A, 5B is on the low pressure side of two spaces having different pressures from the lubricant groove 25l. As a result, the lubricant Lu that has moved from the lubricant groove 25l toward the annular seal member 5A is prevented from moving toward the internal space V by the annular seal member 5A. For this reason, the rotation mechanism 1 can reduce the possibility that the lubricant Lu supplied to the surface of the contact-type seal scatters into the internal space V.

  In the rotation mechanism 1, the housing 2 has a seal fixing spacer 25 that defines the size of the gap 55 and fixes the annular seal member 5 </ b> A. The radially inner side surface 25f of the seal fixing spacer 25 is located between the plurality of annular seal members 5A and 5B, and the lubricant groove 25l is provided on the radially inner side surface 25f of the seal fixing spacer 25. Thereby, the lubricant Lu is easily supplied to the surfaces of the plurality of annular seal members 5A and 5B. For this reason, wear of the annular seal members 5A, 5B or the rotating part 32 is suppressed, and in the first embodiment, the rotating mechanism 1 can reduce the frequency of replacement of components that enhance the sealing performance.

  In the rotation mechanism 1, the lubricant groove 25 l is provided on a part of the radially inner side surface 25 f of the seal fixing spacer 25. Of the radially inner side surface 25f of the seal fixing spacer 25, the distance Δd2 between the annular seal members 5A and 5B side of the lubricant groove 251 and the radially outer surface 32p of the rotating portion 32 is greater than the size of the gap 55. Is also small. Thereby, the lubricant Lu gradually passes through the gaps s2 and s3 between the radially inner side surface 25f and the radially outer surface 32p. For this reason, the rotation mechanism 1 can suppress the situation where the lubricant Lu is supplied in a large amount to the annular seal members 5A and 5B.

(Embodiment 2)
FIG. 5 is an enlarged view of a gap of the rotation mechanism according to the second embodiment. The same components as those described above are denoted by the same reference numerals, and the description thereof is omitted. The rotating mechanism 1 according to the second embodiment includes a lubricant groove 32l that stores lubricant Lu supplied between the annular seal members 5A and 5B and the radially outer surface 32p of the rotating portion 32.

  The lubricant groove 32l is provided in a portion of the radially outer surface 32p of the rotating portion 32 that faces the radially inner side surface 25f of the seal fixing spacer 25. That is, as shown in FIG. 5, the lubricant groove 32l is formed on the annular seal member 5A side end of the radially inner side surface 25f that is perpendicular to the rotation center axis Zr in the radially outer surface 32p of the rotating portion 32. Between the plane S1 passing through the portion and the plane S2 perpendicular to the rotation center axis Zr and passing through the end portion on the annular seal member 5B side of the radially inner side surface 25f. The lubricant groove 32l is provided in an annular shape around the rotation center axis Zr. The lubricant Lu stored in the lubricant groove 32l is, for example, grease. For example, a part of the lubricant Lu protrudes from the lubricant groove 32l and is in contact with the radially inner side surface 25f of the seal fixing spacer 25 by surface tension. Thereby, the lubricant Lu is held by the lubricant groove 32l and the radially inner side surface 25f. Since the lubricant Lu has fluidity, the lubricant Lu is stably supplied from the lubricant groove 32l between the annular seal member 5B and the radially outer surface 32p of the rotating portion 32 by gravity. Thereby, it becomes easy to maintain the state where the lubricant Lu exists between the radially outer surface 32p of the rotating portion 32 and the annular seal member 5B. Further, the lubricant Lu is supplied to the annular seal member 5A by pressure due to slight air leakage between the rotating portion 32 and the annular seal member 5B. The lubricant Lu is also supplied to the annular seal member 5A even when the pressure in the internal space V varies (when the operation of the manufacturing apparatus 100 is started and stopped). Therefore, the wear of the annular seal members 5A, 5B or the rotating part 32 is suppressed, and in the second embodiment, the rotating mechanism 1 can reduce the replacement frequency of components that improve the sealing performance.

  Note that the lubricant groove 32l only needs to be in a range sandwiched between the plane S1 and the plane S2 in the radially outer surface 32p of the rotating portion 32, and may not be provided in an annular shape about the rotation center axis Zr. . The lubricant groove 32l may be provided in an annular shape around a straight line that forms an angle with the rotation center axis Zr, for example.

  As shown in FIG. 5, the lubricant groove 32 l is provided in a part of a portion of the radially outer surface 32 p of the rotating portion 32 that faces the radially inner side surface 25 f of the seal fixing spacer 25. The seal fixing spacer 25 is a distance Δd2 of a gap s2 between a portion of the radial outer surface 32p of the rotating portion 32 closer to the annular seal member 5A than the lubricant groove 32l and a radial inner side surface 25f of the seal fixing spacer 25. Can be set as appropriate to adjust the degree of vacuum. Further, the seal fixing spacer 25 has a gap s3 between a portion of the radially outer surface 32p of the rotating portion 32 that is closer to the annular seal member 5B than the lubricant groove 32l and a radially inner side surface 25f of the seal fixing spacer 25. The degree of vacuum can be adjusted by appropriately setting the distance Δd2. The distance Δd2 is preferably 0.001 mm or more and 0.5 mm or less, for example. Further, the distance Δd2 is smaller than the size of the gap 55. Thereby, the lubricant Lu gradually passes through the gaps s2 and s3 between the radially inner side surface 25f and the radially outer surface 32p. For this reason, the situation where a large amount of the lubricant Lu is supplied to the annular seal members 5A and 5B side is suppressed. In the second embodiment, the gap s2 and the gap s3 are gaps having the same distance Δd2, but may be gaps having different distances.

  As mentioned above, although Embodiment 1 to Embodiment 2 was demonstrated, Embodiment 1 to Embodiment 2 is not limited by the content mentioned above. In addition, at least one of various omissions, substitutions, and changes of components can be made without departing from the gist of the first embodiment to the second embodiment.

DESCRIPTION OF SYMBOLS 1 Rotating mechanism 2 Housing 3 Rotating member 4, 41, 42 Bearing 5A, 5B Annular seal member 8 Electric motor 21 Body portion 22 Housing flange portion 23 Lid portion 23f Radial inner side surface 24 Outer ring stopper member 25 Seal fixing spacer 25a Spacer positioning portion 25b Seal fixing recess 25c Radial inner periphery 25d Radial outer periphery 25f Radial inner side surface 25l Lubricant groove 32 Rotating part 32l Lubricant groove 33 Conveying table (movable member)
41a, 42a Outer ring
41c, 42c Inner ring 51 Lip part 51a Inner peripheral side tip 51d Inner peripheral base part 52 Fixed part 54 Seal flange part 55 Gap 56 Biasing member 56c Bending part 91 Control device 100 Manufacturing apparatus E External space Lu Lubricant V Internal space

Claims (5)

A rotating mechanism that separates two spaces with different pressures,
A housing;
A shaft inserted into the housing;
A bearing provided in the housing and rotatably supporting the shaft;
A rotating portion that is provided at one end of the shaft and rotates together with the shaft, and the radially outer surface faces the housing with a gap of a predetermined size;
A plurality of annular seal members for sealing the gap at different positions;
A lubricant groove for storing a lubricant to be supplied between the annular seal member and a radially outer surface of the rotating portion;
With
At least one annular seal member of the plurality of annular seal members is on the low pressure side of the two spaces having different pressures than the lubricant groove ,
The housing has a seal fixing spacer that defines the size of the gap and fixes the annular seal member;
The radially inner side surface of the seal fixing spacer is at a position between the plurality of annular seal members,
The lubricant groove is provided in a portion of the radially outer surface of the rotating portion facing a radially inner side surface of the seal fixing spacer . The lubricant groove is provided in a part of a portion facing a radially inner side surface of the seal fixing spacer in a radially outer surface of the rotating portion,
Of the radially outer surface of the rotating portion, a distance between a portion closer to the annular seal member than the lubricant groove and a radially inner side surface of the seal fixing spacer is smaller than the size of the gap. The rotation mechanism according to claim 1 . Comprising a rotating mechanism according to claim 1 or 2, and a motor for rotating said shaft, rotary drive. A rotating mechanism according to claim 1 or 2, comprising a movable member for moving the transferred object, and the rotation of the shaft, and a movable member interlocked, the conveying device. Comprising a rotary mechanism according to claim 1 or 2, the manufacturing apparatus.

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