JP4189181B2 - Rotary joint - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotary joint. More specifically, the present invention relates to a rotary joint that is provided in piping of a surface polishing apparatus or the like and supplies slurry fluid, for example, abrasive fluid.
[0002]
[Prior art]
As a related technique of the present invention, there is a rotary joint shown in FIG. FIG. 3 is a cross-sectional view of a rotary joint for slurry fluid.
The rotary joint 100 is provided in a piping passage of a surface polishing apparatus that polishes the surface of a silicon wafer. The rotary joint 100 is provided with a cylindrical joint body 101. A rotating body 102 is rotatably mounted in the inner peripheral surface 101A of the joint body 101.
A flange portion 102A is provided at one end of the rotating body 102, and the flange portion 102A is connected to a polishing pad (not shown).
And it connects so that the fluid passage 103 for slurry provided in the rotary body 102 and the fluid passage of a polishing pad may communicate.
[0003]
A cap-like rotary sealing ring 105 is fitted to the upper end of the rotating body 102 in the figure via an O-ring. The rotary seal ring 105 is provided with a communication passage at the center thereof and communicates with the slurry fluid passage 103, and a seal surface 105A is provided at the front end surface. The rotary seal ring 105 is made of a silicon carbide material.
[0004]
A fixed sealing ring 106 is provided at a position facing the rotary sealing ring 105. The fixed sealing ring 106 is movably fitted to the inner peripheral surface of the fluid passage of the head cover 110 provided at the end of the joint body 101. This fixed sealing ring 106 is a conical shape provided with a cylindrical portion 106A that fits in the supply passage 111 of the head cover 110 via an O-ring attached to the groove of the joint body 101 and an opposing seal surface 106B1 that is in close contact with the seal surface 105A. It is formed in the seal part 106B.
An intermediate passage 107 is provided on the inner periphery of the fixed sealing ring 106, and the intermediate passage 107 communicates with the slurry fluid passage 103 and the supply passage 111. Since the slurry fluid flows from the supply passage 111, the fixed sealing ring 106 must be made of silicon carbide made of a hard material in the same manner as the rotary sealing ring 105 in view of wear. The fixed seal ring 106 is pressed against the rotary seal ring 105 by a coil spring 108.
Since the first mechanical seal 104 is configured independently of the second mechanical seal 116, the axial distance between both parts is increased and the structure is complicated. Further, because of the fitting structure of the cylindrical portion 106A of the fixed sealing ring 106 and the pressing structure by the coil spring, the fixed sealing ring 106 has a longitudinal structure in the axial direction.
[0005]
The rotating mechanical ring 105 and the stationary sealing ring 106 constitute a first mechanical seal 104. A cooling passage 109 is formed between the outer periphery of the first mechanical seal 104 and the joint body 101. The cooling passage 109 communicates with the cooling inlet / outlet 109A, and the cooling water flowing into the cooling passage 109 from the cooling inlet / outlet 109A returns to the cooling inlet / outlet 109A. For this reason, the circulation of the cooling water is not efficient and the cooling effect is inferior.
In the cooling passage 109, it is impossible to cool the second mechanical seal 116 described below. Further, when a fluid such as gas or pure water is circulated through the flow passage 115, wear is promoted simultaneously with heat generation because there is no lubricating action on each seal surface of the second mechanical seal 116 compared to industrial water or the like.
[0006]
Further, the joint main body 101 is provided with an annular non-slurry fluid passage 113 provided on the inner periphery communicating with the fluid passage port 113A. The fluid passage 113 communicates with a flow passage 115 provided in the rotating body 102.
A second mechanical seal 116 is disposed at the connection between the flow passage 115 and the non-slurry fluid passage 113. The second mechanical seal 116 includes a third mechanical seal 117 and a fourth mechanical seal 118.
[0007]
The third mechanical seal 117 includes a first rotary seal ring 117A that is slidably fitted to the rotating body 102, and a first fixed seal ring 117B that is fixed to the joint body 101.
The fourth mechanical seal 118 includes a first rotary seal ring 118A that is slidably fitted to the rotating body 102, and a first fixed seal ring 118B that is fixed to the joint body 101.
The first rotary seal rings 117A and 118A are resiliently pressed to the first fixed seal rings 117B and 118B by the leaf springs 120 and 120, respectively.
[0008]
The flow passage 115 described above includes a first flow passage 115A formed by fitting a sleeve 121 into an annular groove provided in the rotating body 102 and a second flow passage 115B formed by a drill hole.
Since this flow path 115 is composed of the first flow path 115A and the second flow path 115B, it is difficult to process and the number of parts increases. Furthermore, since the rotating body 102 has a large diameter, the second mechanical seal 116 also has a large diameter. Furthermore, in order to form the first flow passage 115A of the annular groove in the rotating body 102, it is difficult to provide another fluid passage. If this fluid passage is forcibly formed, the diameter is further increased.
[0009]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described problems, and a problem to be solved by the invention is to enable the diameter of the flow passage through which the slurry fluid of the first rotary seal ring is circulated. At the same time, the length in the axial direction is made small, and the first fixed sealing ring and each first sealing device are brought close to each other to make the whole sealing device small.
Another object of the present invention is to reduce the size of the opposing sealing device in the axial direction and to prevent the friction and wear of each sealing surface by allowing cooling water to circulate around the opposing sealing device and the outer periphery of the first rotary seal ring.
[0010]
Furthermore, the diameter of the flow path for the slurry can be increased to prevent the flow path from being clogged with the slurry and to prevent the flow path from being worn by the slurry.
Another object of the present invention is to prevent the seal surface from swinging by shortening the length from the bearing supporting the rotating shaft to the first mechanical seal.
[0011]
[Means for Solving the Problems]
The present invention has been made to solve the technical problems as described above, and the technical solution means is configured as follows.
[0012]
The rotary joint of the present invention according to claim 1 has a first communication passage that is hermetically held by the main body and communicates with the slurry fluid supply passage of the main body, and has a sealing surface that surrounds the first communication passage on an end surface. A first fixed seal ring;
The first fixed sealing ring has a second communication passage communicating with the first communication passage, and has a slurry seal surface surrounding the second communication passage and in close contact with the seal surface, and opposite to the slurry seal surface. A rotary shaft having a first rotating seal ring having a fluid sealing surface and a holding surface on its surface, and a slurry fluid flow passage in close contact with the holding surface of the first rotating seal ring and communicating with the second communication passage. When the resilient freely held towards the second sealing surface fitted sealed body into the fluid sealing surface and having a second sealing surface closely to the fluid sealing surface surrounding the rotary shaft The second fixed sealing ring, and a third sealing surface surrounding the rotating shaft on the opposite side of the second sealing surface, and is hermetically fitted to the main body, and the third sealing surface is connected to the second sealing surface. a third fixed seal ring which is held freely elastically toward the opposite side ; And a third rotary seal ring for sealing engagement with the rotary shaft and having a third counter seal face closely opposite to the third sealing surface,
A fluid passage is provided between an inner peripheral passage surface surrounded by the first rotary seal ring, the second fixed seal ring, and the third rotary seal ring, and the rotary shaft, and the fluid passage and the main body have the fluid passage. A first fluid passage for vacuum or fluid that communicates with the first fluid passage through the passage between the second seal surface and the third seal surface, and the fluid passage that the fluid passage has inside the rotary shaft ; It communicates.
[0013]
The rotary joint of the present invention relating to the Claim 1, the first stationary seal ring and the first rotary seal ring and the second stationary seal ring and the third fixed seal ring, for the axial direction of the first rotary seal ring the narrow Kushida shape, it is possible to arrangement the length of the whole is reduced in the axial direction, to be capable of importance as rotary joint, the axial length to facilitate attachment to the device to small Become. Further, another second fluid passage provided in the rotary joint includes a second fixed sealing ring and a third fixed sealing ring in which the first fluid passage of the main body and the fluid passage of the rotating shaft are close to the first rotation sealing ring. Communication between the two is possible even when the rotating shaft is rotating.
At the same time, since the first rotary seal ring is structured to be pressed and held between the first fixed seal ring and the second fixed seal ring by the respective resilient means, the rotary shaft and the first rotary seal ring are held. The surface should just be the joining state which can be sealed. As a result, the slurry fluid can be easily replaced even when the first rotating seal ring is worn. Furthermore, this structure, it is possible the axial length of the first rotary seal ring in the short form, together with the cooling effect from the outer peripheral side of the first rotary seal ring, enabling the cleaning effect. Moreover, consisting of a flow path and the first and second communication passage can be larger in diameter. To this slurry fluid can be effectively prevented from being more wear problems and the communication passage clogged by polishing agents and the polishing agent as it passes through the communication passage.
[0014]
Further, since the first fixed seal ring, the first rotary seal ring, and the first fixed seal ring can be arranged close to each other, the bearing can also be close to the mechanical seal. For this reason, it becomes the structure where the whole became close, and it can prevent effectively that the bearing which supports a rotating shaft supports a 1st rotation sealing ring reliably, and each seal surface decenters and wears at the time of sliding.
[0015]
The rotary joint of the present invention according to claim 2 is disposed in a passage that the second fixed seal ring having the second seal surface and the third fixed seal ring having the third seal surface have in the main body on the outer peripheral side of both seal surfaces. The coil springs are pressed in opposite directions.
[0016]
In the rotary joint according to the second aspect of the present invention, the second fixed seal ring having the second seal surface and the third fixed seal ring having the third seal surface conflict with each other by the coil springs on the outer peripheral sides of both seal surfaces. Since the pressure is pressed in the direction in which the two sealing rings are elastically pressed, it is possible to further press the fluid sealing surface and the slurry sealing surface of the first rotary sealing ring by this elastic force. . For this reason, while being able to make a 1st rotation sealing ring into a thin shape, attachment and removal structure can be simplified.
Furthermore, it is possible to form a fluid passage directly between the inner peripheral passage surface of the second fixed sealing ring and the third fixed sealing ring and the rotation shaft, and to facilitate communication between the first fluid passage and the second fluid passage. In addition, the diameter of the slurry fluid flow passage on the rotating shaft can be increased.
Further, it is possible through the second stationary seal ring and the third fixed seal ring and the passage in which a coil spring on the outer periphery of the first rotary seal ring and the first stationary seal ring, a cooling passage efficient The
[0017]
In the rotary joint of the present invention according to claim 3, the first fixed sealing ring is elastically supported toward the slurry sealing surface by an elastic O-ring in close contact with the main body.
[0018]
In the rotary joint of the present invention according to claim 3, since the first fixed sealing ring seals between the main body by the elastic O-ring, and the first fixed sealing ring is elastically pressed by the elastic O-ring, first stationary seal ring is not necessary to provide a press to Luba roots, the first stationary seal ring with the axial direction can be reduced in size in the radial direction.
At the same time, preventing from the first communication path for the entire shape of the first stationary seal ring can be formed to have a larger diameter, the flow rate of slurry fluids, since it in correspondingly slow, clogging and wear of the communication passage effectively it can. Further, since the space between the first fixed sealing ring and the main body attached with the elastic O-ring can be made large, the slurry fluid is not caught between the narrow fitting surfaces of the first fixed sealing ring and the main body, and the slurry seal. Responsiveness of the first fixed sealing ring to the surface is improved.
[0019]
The rotary joint of the present invention according to claim 4 has one end communicating with the supply port provided in the main body and the other end communicating with the outflow port, the outer periphery of the third seal surface, the outer periphery of the second seal surface, and the first rotation. It has a cooling passage through the outer periphery of the sealing ring.
[0020]
The rotary joint of the present invention according to claim 4, since the second and third fixed seal ring and the first rotary seal ring is continuous shea Lumpur surface each other, the cooling of the continuous each sealing surface with passage The passage allows efficient cooling.
In particular, it is possible to effectively prevent a decrease in the sealing ability due to the slurry fluid on the sliding seal surface between the first fixed seal ring and the first rotary seal ring by the flow of the circulating fluid in the cooling passage, and the first rotary seal. The entire structure is cooled by the thin-walled structure in the axial direction of the ring, so that sliding heat generation and wear of the slurry sealing surface and the fluid sealing surface can be effectively prevented.
[0021]
In addition, the cooling passages effectively prevent the seal surfaces without lubrication from being heated and worn by the vacuum or gas flowing through the fluid passages in the inner peripheral passage surfaces of the second and third fixed sealing rings.
In addition, since the second and third fixed seal rings, the first rotary seal ring, and the first fixed seal ring are arranged in a line in the axial direction, the entire cooling passage is expanded without increasing the length of the cooling passage. It becomes possible to cool in the passage.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a rotary joint according to a preferred embodiment of the present invention will be described in detail with reference to the drawings. In addition, each drawing demonstrated below is drawing based on the design drawing with exact dimension relationship.
[0023]
FIG. 1 is a sectional view of a rotary joint 1 showing a preferred embodiment according to the present invention.
In FIG. 1, a joint body 10 is provided with a through hole 11 through which a rotary shaft 20 passes. The main body 10 is integrated by connecting the first main body 10A, the second main body 10B, and the third main body 10C in the axial direction with bolts A.
The upper end of the through hole 11 of the first main body 10A is formed in the supply passage 12A for introducing the slurry fluid. The supply passage 12A is formed with a pipe screw so that piping can be connected. Further, the through hole 11 below the supply passage 12A is formed with an annular recess 11A having a small tapered surface to which the elastic O-ring 15 is attached. Further, the through hole 11 of the first main body 10A is formed with a large-diameter hole 11B on the lower side in the figure so that the first rotary seal ring 3 can be disposed. The large diameter hole 11B communicates with the outlet 13B of the cooling passage 13.
[0024]
The first fixed sealing ring 2 is disposed in the recess 11 </ b> A of the first main body 10 </ b> A via an elastic O-ring 15. The first fixed sealing ring 2 has a first communication passage 12B passing through the center thereof.
Further, a seal surface 2A is formed at one end of the first fixed seal ring 2 so as to surround the first communication path 12B. Further, a tapered groove 2B is formed on the outer peripheral surface so as to face the annular recess 11A.
The elastic O-ring 15 compressed between the annular recess 11A and the taper groove 2B causes the seal surface 2A of the first fixed seal ring 2 to be used for the slurry of the first rotary seal ring 3 by the action of both contacting taper surfaces. The seal surface 3A is pressed against and is intimately contacted. At the same time, the O-ring 15 effectively prevents the slurry fluid from entering the cooling passage 13. Since the first fixed sealing ring 2 is supported by the elastic O-ring 15, it can be formed smaller in the axial direction and the radial direction than the size of the first communication path 12B.
The elastic O-ring 15 is made of nitrile rubber, fluorine rubber, chloroprene rubber, polyurethane rubber or the like. The first fixed sealing ring 2 is made of silicon carbide, super hard alloy, ceramic or the like.
[0025]
A first rotary seal ring 3 is disposed in the large-diameter hole 11B of the first main body 10A.
Slurry seal face 3A is formed to surround the second communicating passage 2C in the first stationary seal ring 2 side of the first rotary seal ring 3. In addition, a second communication path 12C capable of communicating with the first communication path 12B is formed at the center of the first rotary seal ring 3.
Further, a fluid seal surface 3B is formed on the surface opposite to the slurry seal surface 3A of the first rotary seal ring 3 in the axial direction. A fitting surface (hereinafter also referred to as a holding surface) 3C is formed in the fluid sealing surface 3B, and one end of the rotary shaft 20 is fitted to the fitting surface 3C via an O-ring. .
The first rotary seal ring 3 is movable in the axial direction by a pin 20A provided at one end of the rotary shaft 20, but is configured to rotate together with the rotary shaft 20. The first rotary seal ring 3 and the rotary shaft 20 may be fitted and connected. The first rotating seal ring 3 is also made of a hard material such as silicon carbide.
[0026]
A mechanical seal 4 is attached to the inner peripheral surface 11C of the through hole 11 of the second main body 10B.
The mechanical seal 4 is composed of one sealing device 5 and the other sealing device 6. One sealing device 5 is formed of a fluid sealing surface 3 </ b> B of the second fixed sealing ring 5 </ b> A and the first rotary sealing ring 3. The other sealing device 6 is formed of a third fixed sealing ring 6A and a third rotating sealing ring 6B.
The second fixed sealing ring 5A has an L-shaped cross section, and the second fixed sealing ring 5A has an inner peripheral surface in which the cylindrical outer peripheral surface 5A1 is the through hole 11 of the main body 10 through the O-ring 25. It is fitted to 11C so as to be movable in the axial direction, and is held non-rotatable by a fixing pin provided on the second main body 10B. The second seal surface 5A3 provided on the flange-like end surface is pressed by a coil spring (spring means) 16 and is in close contact with the fluid seal surface 3B of the first rotary seal ring 3. The inner peripheral passage surface 5A4 of the second fixed sealing ring 5A is spaced from the rotary shaft 20 to form the fluid passage 14.
[0027]
The other sealing device 6 is formed of a third fixed sealing ring 6A and a third rotating sealing ring 6B. The third fixed sealing ring 6A is formed in the same shape as the second fixed sealing ring 5A, and is arranged symmetrically with the second fixed sealing ring 5A with the central line of the inner peripheral surface 11C of the second main body 10B as a boundary.
Similar to the second fixed seal ring 5A, the third fixed seal ring 6A is provided with a cylindrical outer peripheral surface 6A1 and a third seal surface 6A3 on the tip surface. Further, it is held non-rotatable by a fixing pin provided in the second main body 10B.
Then, the inner peripheral passage surface 6A4 of the third fixed sealing ring 6A forms a fluid passage 14 with a space between the rotary shaft 20 similarly to the second fixed sealing ring 5A. A gap is formed between the second fixed seal ring 5A and the third fixed seal ring 6A to communicate with the first fluid passage 14A.
Since each of the sealing rings 5A, 6A, 6B of the one sealing device 5 and the other sealing device 6 does not pass the slurry fluid, in addition to the hard material such as silicon carbide, carbon or the like can be used as necessary. Is possible.
[0028]
The second fixed sealing ring 5A and the third fixed sealing ring 6A are elastically pressed in directions opposite to each other by the spring means of the coil spring 16. The coil spring 16 is inserted and held in a passage 13C provided in the second main body 10B. This passage 13 </ b> C communicates with the cooling passage 13.
The main body 10 is provided with a supply port 13A for supplying cooling water to the cooling passage 13 on the other sealing device 6 side, and an outflow port 13B for discharging the cooling water is formed on the first fixed sealing ring 2 side. Has been. The cooling passage 13 is excellent in the cooling effect because the distance from the other sealing device 6 to the first fixed sealing ring 2 is short. Further, since the slurry sealing surface 3A and the fluid sealing surface 3B of the first rotary seal ring 3 are cooled from the outer peripheral surface, the cooling effect of each sealing surface and the cleaning effect of each sealing surface are also exhibited.
[0029]
On the other hand, the third rotary seal ring 6B that is in close contact with the third seal surface 6A3 of the third fixed seal ring 6A has an L-shaped cross section, and the cylindrical inner peripheral surface 6B1 is fitted to the rotary shaft 20 via the O-ring. I wear it.
A third opposed seal surface (hereinafter simply referred to as a third seal surface) 6B3 provided on the end surface of the third rotary seal ring 6B is in close contact with the third seal surface 6A3 of the second fixed seal ring 6A. The third rotary seal ring 6B is held by a drive pin provided on the rotary shaft 20 and rotates.
Further, a packing 17 that seals between the outer peripheral surface of the third rotary sealing ring 6B and the main body 10 is fitted. This packing 17 seals the communication between the cooling passage 13 and the bearing 21 side.
[0030]
Two bearings 21 arranged in parallel are provided between the through hole 11 in the lower portion of the packing 17 of the main body 10 and the rotary shaft 20. The rotating shaft 20 is rotatably held via a bearing 21 held by the main body 10. Since the bearing 21 is attached near the mechanical seal 4, the mechanical seal 4 and the first rotary seal ring 3 are stably supported.
[0031]
On the stepped surface of the rotating shaft 20, a fluid passage ( also referred to as a second fluid passage ) 14 having a hole communicating with the fluid passage 14 in the mechanical seal 4 is formed penetrating in the axial direction. The main body 10 is provided with a first fluid passage 14 </ b> A penetrating between one sealing device 5 and the other sealing device 6.
A vacuum device (not shown) communicates with the outside of the first fluid passage 14A through a pipe. And the workpiece etc. which were grind | polished via the 2nd fluid channel | path 14 are vacuum-sucked, or the slurry fluid adhering to a workpiece is sucked.
In particular, the fluid passage 14 is used for evacuation. In the vacuum passage, no fluid is present in the fluid seal surface 3B, the second seal surface 5A3, and the third seal surfaces 6A3 and 6B3. 5A3, 6A3 , and 6B3 tend to generate heat and wear rapidly, but are effectively prevented by the cooling water flowing through the cooling passage 13.
[0032]
The main body 10 is further provided with a drain hole 18. The drain hole 18 is to be discharged when cooling water or the like leaks.
Further, a flange portion is formed at the lower portion of the rotary shaft 20 in the figure, and other components such as the air supply rotary joint 30 are attached by bolts B through the flange. The rotating shaft 20 is formed with a flow passage 12 communicating with the second communication passage 12 </ b> C with a large diameter on the axis. The slurry fluid flows through the flow passage 12.
[0033]
FIG. 2 is a cross-sectional view of the air supply rotary joint 30.
In FIG. 2, a sleeve 33 </ b> A is fitted on the rotation shaft 33.
Further, a communication path 12 communicating with the flow path 12 of the rotary shaft 20 in FIG. 1 is formed in the axial direction. Furthermore, a first air passage 31 and a second air passage 32 are formed in the rotary shaft 33 through the outer sleeve 33A and formed in a hole bent in an L shape in the axial direction therefrom. Yes.
Further, a fluid passage 14 communicating with the fluid passage 14 of the rotary joint 1 for supplying slurry fluid shown in FIG.
[0034]
On the other hand, the main body 40 is provided with a first air supply port 31 </ b> A communicating with the first air passage 31.
Further, the main body 40 is provided with a second air supply port 32 </ b > B that communicates with the second air passage 32. Then, on both sides of the first air supply port 31A and a second air supply 32 B in between fitting the sleeve 33A and the body 40 are fitted ring-shaped packing 35 in three places. The packings 35 , 35 , 35 seal both sides of the sleeve 33A communicating with the air passages 31, 32 and the air supply ports 31A, 32A.
The packings 35 , 35 , 35 have a special shape in which the inner peripheral side is constituted by a fluororesin ring and the outer peripheral side is constituted by a rubber ring. The rubber ring and the fluororesin ring are fitted and integrated with each other.
The outer peripheral surface which slides with the packing 35 of the sleeve 33A is subjected to hard plating indicated by fine hatching. And it is comprised so that the sliding surface with each packing 35,35,35 may not wear. Reference numeral 40A denotes a container such as a drain receiver.
[0035]
In the rotary joint 1 configured as described above, as an example, the slurry fluid flowing in the flow passage 12 is a fluid containing an abrasive for polishing the liquid crystal glass. The fluid passage 14 is a vacuum passage used for an adsorption means for adsorbing the liquid crystal glass and moving it from the processing apparatus to another. Alternatively, the processing liquid or the like adhering to the liquid crystal glass is sucked out using a vacuum passage.
Since this slurry fluid polishes the surface of liquid crystal glass with an abrasive, the slurry fluid contains a high concentration abrasive.
When the flow passage 12 has a small diameter as in the prior art, there is a problem that this abrasive clogs the flow passage 12. Further, if the flow passage 12 has a small diameter, the polishing agent must be flowed with a high-speed fluid because of the polishing speed. Thus, if the abrasive is flowed at a high speed, the abrasive flowing through the flow passage 12 is worn away as if the flow passage 12 was scraped off, causing a failure.
[0036]
Furthermore, since the fluid passage 14 can be formed directly between the inner peripheral surface of the mechanical seal 4 and the rotary shaft 20, the mechanical seal 4 is made smaller than the flow passage 12 even if the flow passage 12 has a larger diameter. It becomes possible. For this reason, since the peripheral speed of 2nd seal surface 5A3, 3rd seal surface 6A3, and 3rd seal surface 6B3 can be made small, sliding heat_generation | fever of each seal surface 5A3, 6A3, 6B3 can be prevented. Further, even if the fluid passage 14 is a vacuum passage, it is possible to prevent the seal surfaces 5A3, 6A3, and 6B3 from being worn.
Furthermore, since the cooling water circulates from the outer periphery of the mechanical seal 4 to the outer periphery of the first fixed sealing ring 2 through the cooling passage 13, heat generation and wear of each seal surface against the slurry fluid and vacuum are effectively prevented.
The rotary joint 1 is also used for polishing a semiconductor wafer or the like. Furthermore, the fluid passage 14 is also used as a flow path for air and pure water as necessary.
【The invention's effect】
According to the rotary joint of the present invention, since the first fixed sealing ring is elastically supported by the elastic O-ring, the entire first fixed sealing ring can be reduced in size even if the flow passage through which the slurry is passed has a large diameter.
In addition, the first rotary seal ring having a slurry seal surface at one end and a fluid seal surface at the other end and pressed against the first fixed seal ring by a spring means included in the mechanical seal has a short axial length. In addition, the effect of simplifying the holding of the rotating shaft can be achieved.
With these configurations, the axial lengths of the first fixed seal ring and the first rotary seal ring can be shortened even if the flow passage has a large diameter. For this reason, slurry fluid is not clogged in the flow passage, and wear of the flow passage can be prevented. Furthermore, there is an effect that it is possible to increase the polishing rate by increasing the volume of the slurry fluid flowing through the flow passage.
[0038]
Further, the holding of the first fixed sealing ring by the elastic O-ring that constitutes the spring means and the configuration in which the first rotary sealing ring can be easily held on the rotating shaft can facilitate the assembly of the entire rotary joint and reduce the assembly cost. There is an effect. In addition, the axial length is shortened to reduce the restriction of the installation location on the apparatus, and the industrial application of this rotary joint is expanded.
[Brief description of the drawings]
FIG. 1 is a sectional view of a rotary joint showing an embodiment according to the present invention.
FIG. 2 is a cross-sectional view of an air supply rotary joint attached to the rotary joint according to the present invention.
FIG. 3 is a cross-sectional view of a conventional rotary joint.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Rotary joint 2 1st fixed seal ring 2A Seal surface 2B Tapered groove 3 1st rotation seal ring 3A Slurry seal surface 3B Fluid seal surface 3C Fitting surface (holding surface)
4 Mechanical seal 5 One sealing device 5A Second fixed sealing ring 5A1 Cylindrical outer peripheral surface 5A3 Second sealing surface 5A4 Inner peripheral passage surface 6 Other sealing device 6A Third fixed sealing ring 6A1 Cylindrical outer peripheral surface 6A3 Third sealing surface 6A4 Inside Circumferential passage surface 6B Third rotary seal ring 6B1 Cylindrical inner peripheral surface 6B3 Third seal surface 10 Main body 10A First main body 10B Second main body 10C Third main body 11 Through hole 12 Flow passage 13 Cooling passage 13A Supply port 13B Outlet 13C Passage 14 Fluid passage (second fluid passage)
14A First fluid passage 15 Elastic O-ring 16 Spring means (coil spring)
17 Packing 18 Drain 20 Rotating shaft 20A Pin 21 Bearing 25 O-ring

Claims (4)

A first fixed sealing ring having a first communication path that is hermetically held by the main body and communicates with the slurry fluid supply path of the main body and has a seal surface that surrounds the first communication path at an end surface;
The first fixed sealing ring has a second communication passage communicating with the first communication passage, and has a slurry seal surface surrounding the second communication passage and in close contact with the seal surface, and opposite to the slurry seal surface. A first rotating seal ring having a fluid sealing surface and a holding surface on the surface thereof;
A rotating shaft having a slurry fluid flow passage in close contact with a holding surface of the first rotary seal ring and communicating with the second communication passage;
The second seal surface surrounds the rotating shaft and is in close contact with the fluid seal surface and is hermetically fitted to the main body so that the second seal surface is held elastically toward the fluid seal surface . A second fixed seal ring;
A third seal surface is provided on an end surface surrounding the rotation shaft on the side opposite to the second seal surface, and the third seal surface is hermetically fitted to the main body, and the third seal surface is elastically moved toward the side opposite to the second seal surface. A third fixed sealing ring held freely;
A third rotating seal ring having a third opposing seal surface that is in close contact with the third seal surface and is hermetically fitted to the rotary shaft ;
A fluid passage is provided between the rotary shaft and an inner peripheral passage surface surrounded by the first rotary seal ring, the second fixed seal ring, and the third rotary seal ring;
The fluid passage communicates with a vacuum or fluid first fluid passage in the main body via a passage between the second seal surface and the third seal surface, and the fluid passage is connected to the rotating shaft. the second fluid passage and a rotary joint for communicating with the interior of the. A coil in which a second fixed seal ring having the second seal surface and a third fixed seal ring having the third seal surface are disposed in a passage provided in the main body on the outer peripheral side of the second seal surface and the third seal surface. The rotary joint according to claim 1, wherein the rotary joint is pressed in a direction opposite to each other by a spring. 3. The rotary joint according to claim 1, wherein the first fixed sealing ring is elastically supported toward the slurry sealing surface by an elastic O-ring in close contact with the main body. A cooling passage that has one end communicating with the supply port provided in the main body and the other end communicating with the outflow port and passing through the outer periphery of the third seal surface, the outer periphery of the second seal surface, and the outer periphery of the first rotary seal ring. The rotary joint according to claim 1, 2, or 3.

Images