JP5367423B2 - Sealing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing device which has the sealing characteristics suitable for a fluid such as a high-concentration slurry. <P>SOLUTION: The inside of a machine is provided with a non-contact seal and the outside thereof is provided with a contact seal, and first and second partition walls 510, 530 are formed on the inner side of the inside seal to provide a first gas chamber 410 and a second gas chamber 420. Floating rings 520, 540 are provided to the inner peripheral parts of the first and second partition walls 510, 530 so that a fluid flows from both the inner side seal and the inside of the machine into the second gas chamber 420. The fluid flowing into the second gas chamber 420 is discharged through the outlet 421 of the second gas chamber 420. The slurry can be properly sealed by the flow of buffer gas and the non-contact seal, and the fluid is reliably prevented from leaking to the outside of the machine by the contact seal. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a sealing device suitable for use in a fluid machine that handles a high-concentration slurry liquid or a high-viscosity solution such as a pulverizer or a disperser.

  A double mechanical seal in which non-contact seals are combined is often used as a seal device for a fluid machine that handles a high-concentration slurry or a high-viscosity solution such as a pulverizer or a disperser. In this type of apparatus, the in-machine mechanical seal is usually circulated by pressurizing and circulating a circulating fluid (liquid or fluid) at a higher pressure than the in-machine fluid in an intermediate chamber between the atmosphere side seal and the in-machine seal. The leakage direction is set to the inside of the machine from the intermediate chamber, so that the sealed fluid does not leak out of the machine.

  In addition, a shaft seal device (for example, Patent Document 1) in which a non-contact type seal is installed on both the atmosphere side and the inside of the machine to prevent the sealed fluid from entering the intermediate chamber, and the non-contact type seal is also provided on the atmosphere side. A shaft seal device for liquefied gas that is installed both inside the machine, has a plurality of seal chambers on the sealed fluid side of the machine inner seal, and gasifies the liquid before the sealed fluid contacts the machine inner seal. (For example, patent document 2) etc. are also disclosed.

JP 2002-235858 A Japanese Patent No. 3517710

However, in the conventional sealing device as disclosed in Patent Document 1, for example, if the in-machine seal fails or is damaged, a large amount of circulating fluid in the intermediate chamber flows into the aircraft, and the circulating fluid In the case of a liquid, there is a problem of diluting the product medium, and when the circulating fluid is a gas, the pulverizing ability and the dispersing ability may be lowered.
Further, when the medium inside the machine adheres to the secondary seal of the machine inside seal, there is a possibility that the operation characteristics change and an operation failure or the like occurs.
Further, when the non-contact seal is used on both the atmosphere side and the inside of the machine, it is necessary to supply a large amount of circulating fluid to the intermediate chamber.

  Further, in the shaft seal device for liquefied gas disclosed in Patent Document 2, since the leak direction of the machine inner seal is from the machine inner side to the intermediate chamber direction and the leak direction of the atmosphere side seal is from the intermediate chamber to the atmosphere side direction, There is also a problem that the sealed fluid may leak out of the machine.

  The present invention has been made in view of such problems, and its purpose is to obtain good sealing characteristics even for fluids such as high-concentration slurries and high-viscosity solutions. Intrusion can be prevented, and the sealed fluid can be prevented from flowing out of the machine. Even if the sealed fluid adheres to the secondary seal, it does not hinder the operation of the secondary seal. An object of the present invention is to provide a sealing device that does not require a large amount of fluid.

In order to solve the above-mentioned problem, the sealing device of the present invention according to claim 1 is a sealing device that seals between a hole of a housing and a rotary shaft that passes through the hole of the housing, and the rotary shaft A rotary ring having a seal surface at one end in the axial direction of the rotary shaft, and a stationary ring having a seal surface installed in the housing and disposed opposite to the seal surface of the rotary ring. A dynamic pressure generating groove is formed in one or both of the sealing surface of the rotating ring and the sealing surface of the stationary ring, and the sealing surface of the rotating ring and the stationary ring are rotated by the rotation of the rotating shaft. An in-machine non-contact seal that is in a non-contact state with each other, and an outside end of the in-machine non-contact seal, installed on the rotary shaft, and one end of the rotary shaft in the axial direction Has a sealing surface A rotating ring, and a stationary ring having a sealing surface disposed on the housing and disposed opposite to the sealing surface of the rotating ring, wherein the sealing surface of the rotating ring and the sealing surface of the stationary ring are in close contact with each other A space between the non-contact seal and the non-contact seal and the contact seal, the intermediate chamber through which buffer gas flows, and the non-contact seal inside the housing inside the housing. A first partition wall that is installed, divides a space around the rotating shaft in the axial direction, and forms a first gas chamber with the non-machine-side non-contact seal; and the first partition inside the housing A second partition wall that is further installed on the inner side of the wall, partitions the space around the rotation shaft in the axial direction, and forms a second gas chamber between the first partition wall and the second partition wall, the second gas chamber is formed with an exhaust port The pressures of the intermediate chamber, the first gas chamber, the second gas chamber, and the interior space are the pressure of the intermediate chamber, the pressure of the first gas chamber, the pressure of the second gas chamber, It is comprised so that it may become low in order of the pressure of the interior space .

In the sealing device of the present invention according to claim 2 , a minute gap is formed between the outer peripheral surface of the rotating shaft and the inner peripheral portion of one or both of the first partition wall and the second partition wall. And a floating ring is installed to flow the fluid in the direction of the second gas chamber.

Further, in the sealing device of the present invention according to claim 3 , the contact seal has a predetermined range along a circumferential direction on one or both of the seal surface of the rotating ring and the seal surface of the stationary ring. A first groove formed in the recess and not communicating with the outside, and a second groove formed in the recess within a predetermined range along the circumferential direction and communicated with the outside so that pressure can be introduced from the outside. One or more grooves are formed, respectively.

According to a fourth aspect of the present invention, the non-contact seal includes a rubber spring as a secondary seal.

  According to the sealing device of the present invention according to claim 1, since the circulating fluid flows from the intermediate chamber to the inner side of the machine with the inner side seal as a non-contact seal, the fluid such as high-concentration slurry and high-viscosity solution is used. Also, good sealing characteristics can be obtained, and on the other hand, since the atmosphere side seal is constituted by a contact seal, it is possible to prevent the sealed fluid from flowing out of the apparatus. Further, the amount of circulating fluid can be greatly reduced as compared with a sealing device having a non-contact sealing configuration.

Further, according to the sealing device of the present invention according to claim 1, it is possible to the sealed fluid by a first partition wall and the second partition wall is less likely to flow to the inboard side contactless seal direction, Good sealing characteristics can always be obtained even for fluids such as high-concentration slurries and high-viscosity solutions, and the sealed fluid can be reliably prevented from flowing out of the machine. Further, since the buffer gas (circulating fluid) flowing inside the machine that has passed through the machine non-contact seal is discharged from the second gas chamber, the circulating fluid can be prevented from entering the machine.

Further, according to the sealing device of the present invention according to claim 2 , since the possibility of the sealed fluid flowing in the in-machine non-contact sealing direction can be further reduced by installing the floating ring, the high concentration slurry It is always possible to obtain good sealing characteristics even for fluids such as high-viscosity solutions, and it is possible to almost certainly prevent the sealed fluid from flowing out of the machine. It is possible to reliably discharge the buffer gas (circulating fluid) flowing through the second gas chamber from the second gas chamber and prevent the circulating fluid from entering the machine.

Further, according to the sealing device of the present invention according to claim 3, even in the outboard contact seal 300 formed as a contact seal, the sliding load can be reduced, and the wear resistance is high and the durability is high. A sealing device can be provided.

Further, according to the sealing device of the present invention according to claim 4 , it is possible to provide a sealing device that does not hinder the operability of the secondary seal even if the sealed fluid adheres to the secondary seal.

FIG. 1 is a diagram showing a configuration of a sealing device according to an embodiment of the present invention, and is a cross-sectional view of the sealing device cut along a plane passing through an axis. FIG. 2 is an enlarged view of the vicinity of the in-machine non-contact seal and the out-of-machine contact seal of the sealing device shown in FIG. 3A and 3B are diagrams showing the structure of the rotary ring of the in-machine non-contact seal. FIG. 3A is a front view of the rotary ring, and FIG. 3B is the dynamic pressure generation of FIG. It is a figure which shows the cross-sectional structure of the circumferential direction of a groove | channel. 4A and 4B are diagrams showing the structure of the stationary ring of the outboard contact seal. FIG. 4A is a front view of the stationary ring, and FIG. 4B is AO- of FIG. 4A. It is sectional drawing along A '.

An embodiment of a sealing device of the present invention will be described with reference to FIGS.
In the present embodiment, a sealing device that seals a gap between a rotating shaft and a housing of an apparatus body in an apparatus such as a pulverizer or a disperser that handles a high-concentration slurry or a highly viscous solution will be described.

First, a schematic configuration of the sealing device 10 will be described with reference to FIG.
The seal device 10 includes first to third seal housings 161 to 163, an in-machine non-contact seal 200, an out-of-machine contact seal 300, first and second partition walls 510, 530, and floating rings 520, 540. Have.
In the sealing device 10, the intermediate chamber 400 is provided between the outboard contact seal 300 and the inboard contactless seal 200, and the first gas is provided between the inboard contactless seal 200 and the first partition wall 510. In the chamber 410, a second gas chamber 420 is formed between the first partition wall 510 and the second partition wall 530.
In the present embodiment, the outside space A is an atmospheric region.

  The rotary shaft 2 passes through a hole 5 formed in the housing 4 of the device body and passes through the machine interior space Q and the machine exterior space A in which slurry liquid or the like is accommodated. 4 and the rotating shaft 2, and prevents leakage of the sealed fluid from the machine interior space Q to the machine exterior space A.

  Further, in the sealing device 10, the pressure in the second gas chamber 420, the pressure in the first gas chamber 410, and the pressure in the intermediate chamber 400 sequentially increase with respect to the fluid pressure in the interior space Q. Set the pressure in each space as follows. As a result, the sealed fluid can be properly sealed, and the slurry and high-viscosity fluid inside the machine can hardly flow to the machine-side non-contact seal 200 side, so that the machine-side non-contact seal 200 and the rubber spring 240 of the secondary seal can be used. The structure prevents the slurry and high-viscosity fluid from coming into contact with each other and sticks, and maintains good sealing characteristics.

Further, in the sealing device 10, by providing the floating rings 520 and 540 on the inner peripheral side of the first partition wall 510 and the second partition wall 530, the fluid flows in the direction of the second gas chamber 420. . Further, the fluid flowing into the second gas chamber 420 is recovered through the exhaust port 421. As a result, it becomes more difficult for the fluid inside the machine to come into contact with the machine non-contact seal 200, and the buffer gas (circulating fluid) flows into the machine interior space Q to dilute the product fluid, or to pulverize the device body. In this configuration, the processing capacity such as dispersion is not reduced.
The sealing device 10 of the present embodiment is a sealing device having such a schematic configuration.

  Next, the configuration of the in-machine non-contact seal 200, the out-of-machine contact seal 300, and the periphery thereof will be described in detail mainly with reference to FIG.

  The in-machine non-contact seal 200 has a rotating ring 210 and a stationary ring 220. The rotating ring 210 is disposed on the inner periphery of the first seal housing 161, is fixed to the rotating shaft 2 by the first sleeve 111, and rotates together with the rotating shaft 2. The stationary ring 220 is held non-rotatably on the inner circumferences of the first seal housing 161 and the second seal housing 162 by the rubber spring 240 and the knock pin 253. The rotating ring 210 and the stationary ring 220 are pressed against each other by the axial biasing force of the compression spring 251 to form the seal surface 200S against the opposite end surfaces (seal surfaces) 211 and 221. A pressure generating groove 212 (see FIG. 3) is formed, and the seal surface 211 of the rotating ring 210 and the seal surface 221 of the stationary ring 220 are brought into non-contact with the rotation of the rotating shaft 2. As described above, the in-machine non-contact seal 200 is a non-contact seal that seals and separates the inner and outer peripheral spaces of the seal surface in a state where the seal surfaces 211 and 221 are not in contact.

  The outboard contact seal 300 includes a rotating ring 310 and a stationary ring 320. The rotary ring 310 is disposed on the inner periphery of the third seal housing 163 on the inside of the machine, is fixed to the rotary shaft 2 by the first sleeve 111, the second sleeve 131, and the sleeve collar 147 and rotates together with the rotary shaft 2. To do. The stationary ring 320 is non-rotatably installed on the inner periphery of the third seal housing 163 on the outside of the machine. The rotating ring 310 and the stationary ring 320 come into close contact with each other at the end faces (seal surfaces) 311 and 321 by the axial biasing force of the compression spring 351 to form a sliding seal surface 300S. As described above, the outside seal 300 is a contact seal in which the seal surfaces 311 and 321 slide closely to seal and separate the inner and outer spaces of the seal surface.

  A first sleeve 111 is fitted and fixed to the outer periphery of the rotary shaft 2 so as to be rotatable integrally with the rotary shaft 2. A flange 113 is integrally formed at the end of the first sleeve 111 on the inside of the machine. An O-ring groove 115 is formed on the inner peripheral surface of the region where the flange 113 of the first sleeve 111 is formed, and an O-ring 117 is attached thereto. The O-ring 117 prevents the sealed fluid from flowing into the gap between the first sleeve 111 and the rotating shaft 2. The material of the O-ring 117 is selected according to the type of fluid to be sealed, and is, for example, synthetic rubber.

  A labyrinth seal ring 119 is attached to the outer periphery of the flange 113 of the first sleeve 111. The labyrinth seal ring 119 is a member in which convex portions and concave portions (grooves) are alternately formed along the axial direction on the outer peripheral surface, and the convex portions are close to the inner peripheral surface of the first seal housing 161. This arrangement prevents the slurry from entering the vicinity of the sealing surface of the in-machine non-contact seal 200 from between the outer peripheral surface of the flange 113 of the first sleeve 111 and the inner peripheral surface of the first seal housing 161. ing. The labyrinth seal ring 119 is made of a fluororesin such as PTFE, for example.

  A rotating ring 210 that constitutes an in-machine non-contact seal 200 is disposed on the outside of the flange 113 of the first sleeve 111. An O-ring groove 123 is formed on the surface of the flange 113 on the rotary ring 210 side, and an O-ring 125 is attached. The O-ring 125 is pressed against the back surface of the rotating ring 210 and seals between the rotating ring 210 and the flange 113. Similar to the O-ring 117, the O-ring 125 is made of synthetic rubber or the like.

  A key groove 127 is formed on the inner peripheral surface of the rotating ring 210. A key 129 formed on the first sleeve 111 is locked in the key groove 127, whereby the rotary ring 210 is fixed to the first sleeve 111 and can be rotated together with the rotary shaft 2. .

  As shown in FIG. 3A, a plurality of dynamic pressure generating grooves 212 are formed in the circumferential direction on the seal surface 211 of the rotary ring 210 of the in-machine non-contact seal 200. The dynamic pressure generating groove 212 has an L-shape when viewed from the plane side, a radial portion 213 that communicates directly with the intermediate chamber 400, and a circle that communicates with the outer diameter portion of the radial portion 213 and extends in the circumferential direction. And a circumferential portion 214. A pair of dynamic pressure generating grooves 212 adjacent to each other are arranged in line symmetry. In this embodiment, groups of six pairs of dynamic pressure generating grooves 212 arranged symmetrically with each other are arranged on the seal surface 211 of the rotating ring 210 at substantially equal intervals along the circumferential direction.

  As shown in FIG. 3B, the groove depth T1 of each dynamic pressure generating groove 212 is not a uniform depth along the circumferential direction of the rotating ring 210, but is maximum at a position intersecting with the radial portion 213. And is shallowest at the opposite end along the circumferential direction. By setting the non-uniform groove depth in this way, when the rotary ring 210 rotates relative to the stationary ring 220, the pressure increases at a portion where the groove depth is shallow. As a result, a gap C <b> 1 is formed between the seal surface 211 of the rotating ring 210 and the seal surface 221 of the stationary ring 220. Since the dynamic pressure generating groove 212 communicates with the intermediate chamber 400, the buffer gas in the intermediate chamber 400 is drawn into the dynamic pressure generating groove 212, and the gap C1 becomes a barrier layer 215 made of buffer gas.

In the in-machine non-contact seal 200, the dynamic pressure generating groove 212 communicates with the intermediate chamber 400 in which the gas pressure of the buffer gas is formed higher than the fluid pressure of the first gas chamber 410. Further, the outer peripheral side of the in-machine non-contact seal 200 is the first gas chamber 410, and centrifugal force acts on the dynamic pressure generating groove 212. As a result, the barrier layer 215 can effectively prevent the fluid inside the machine from entering the intermediate chamber 400.
Further, in the present embodiment, as shown in FIG. 3A, a set of dynamic pressure generating grooves 212 formed symmetrically with each other is formed on the seal surface 211 of the rotating ring 210. Regardless of the direction of rotation of the ring 210, the dynamic pressure generating groove 212 has the same function.

  The rotary ring 210 of the in-machine non-contact seal 200 is made of a hard material such as SiC, cemented carbide or ceramic coating material.

Returning to FIG. 2, the second sleeve 131 is fitted and fixed to the outer periphery of the axially central portion of the first sleeve 111. The second sleeve 131 is locked to a key 129 formed on the first sleeve 111, and both rotate integrally with the rotary shaft 2. A flange 133 is integrally formed at the end of the second sleeve 131 on the atmosphere side.
An O-ring groove 135 is formed in a region of the outer peripheral surface of the first sleeve 111 where the second sleeve 131 is fitted, and an O-ring 137 is attached. As a result, the space between the first sleeve 111 and the second sleeve 113 is sealed, and the buffer gas flowing into the intermediate chamber 400 or the fluid existing in the outside space A is in contact with the first sleeve 111 and the second sleeve 113. To prevent inflow. The material of the O-ring 137 is made of, for example, synthetic rubber like the O-ring 117. However, the O-ring 137 is disposed in the intermediate chamber 400 and does not come into contact with the fluid to be sealed in the normal state. It is also possible to make the material cheaper than the O-rings 117 and 125.

  On the atmosphere side of the flange 133, a rotating ring 310 constituting the outside contact seal 300 is disposed. An O-ring groove 139 is formed on the surface of the flange 133 on the rotary ring 310 side, and an O-ring 141 is attached. The O-ring 141 is pressed against the back surface of the rotary ring 310 of the outside contact seal 300 and seals between the rotary ring 310 and the flange 133. The O-ring 141 may be made of the same material as the O-ring 137.

A key groove 143 is formed on the inner peripheral surface of the rotary ring 310 of the outside contact seal 300, and the key 145 fixed to the first sleeve 111 is locked to the key groove 143. As a result, the rotating ring 310 is fixed to the first sleeve 111 and can rotate with the rotating shaft 2.
The rotating ring 310 of the out-of-machine contact seal 300 is also made of a hard material such as SiC, cemented carbide, or ceramic coating material.

  A sleeve collar 147 is fixed to the outer periphery of the atmosphere side end of the first sleeve 111 by a set screw 149. Further, a fixing flange 151 is integrally formed at the end of the sleeve collar 147 on the atmosphere side.

  A first seal housing 161, a second seal housing 162, and a third seal housing 163 are detachably fixed by bolts 165 to the atmosphere side end portion of the housing 4 of the apparatus main body. The first seal housing 161 and the second seal housing 162 are sandwiched and fixed between the third seal housing 163 and the housing 4.

  The third seal housing 163 has a gas pressurization supply port 167 for supplying a buffer gas, from which high-pressure buffer gas can be supplied to the intermediate chamber 400. A buffer gas supply device (not shown) is connected to the gas pressurization supply port 167, and from the fluid pressure of the sealed fluid accommodated in the interior space Q through the gas pressurization supply port 167 and into the intermediate chamber 400. The high-pressure buffer gas is also poured. In addition, although it does not specifically limit as buffer gas, For example, inert gas, such as nitrogen gas, is preferable. The pressure of the supplied buffer gas is set according to the pressure of the sealed fluid. For example, in the intermediate chamber 400, the pressure of the sealed fluid is preferably about 0.2 to 0.3 MPa higher than the pressure of the sealed fluid. is there.

An O-ring groove 169 is formed on the outer peripheral surface of the first seal housing 161, and an O-ring 171 is attached. The O-ring 171 is pressed against the inner peripheral surface of the hole 5 of the housing 4 to seal the gap between the first seal housing 161 and the housing 4.
An O-ring groove 173 is formed on the outer peripheral surface of the second seal housing 162 on the inside of the machine, and an O-ring 175 is attached. The O-ring 175 is pressed against the inner peripheral surface of the first seal housing 161 to seal the gap between the first seal housing 161 and the second seal housing 162.
Furthermore, an O-ring groove 177 is formed on the outer peripheral surface of the second seal housing 162 on the outside of the machine, and an O-ring 179 is attached. The O-ring 179 is pressed against the inner peripheral surface of the third seal housing 163 to seal the gap between the second seal housing 162 and the third seal housing 163.

On the inner peripheral surface of the second seal housing 162, a retainer portion 181 that protrudes in a ring shape radially inward is formed. The retainer portion 181 is disposed on the inner side of the flange portion 133 of the second sleeve 131 installed on the rotating shaft 2.
The retainer portion 181 has a plurality of recesses 183 that open toward the inner side in the axial direction. The plurality of recesses 183 are equally arranged on the ring-shaped retainer portion 181. The base end of the compression spring 251 is held in the recess 183. The tip of the compression spring 251 is in contact with the back surface (atmosphere side end surface) of the stationary ring 220 of the in-machine non-contact seal 200 disposed in the inner circumferential hollow portion of the first seal housing 161, and the stationary ring 220 is axially moved. Press inside the machine. As a result, the stationary ring 220 of the in-machine non-contact seal 200 is pressed against the rotating ring 210 of the in-machine non-contact seal 200.

  The retainer portion 181 is provided with a knock pin 253 toward the inner side in the axial direction. The knock pin 253 is engaged with a notch 223 formed on the back surface (atmosphere side end surface) of the stationary ring 220 of the in-machine non-contact seal 200. As a result, the stationary ring 220 of the in-machine non-contact seal 200 is locked to the second seal housing 162 so as not to rotate relative to the second seal housing 162.

  The inner peripheral corner portion on the machine inner side where the first seal housing 161 and the second seal housing 162 are integrally connected is configured as a rubber spring installation portion 185 to which the outer peripheral portion of the rubber spring 240 is fitted and fixed. ing. The rubber spring 240 is a rubber ring-shaped elastic member, and an inner peripheral portion thereof is fitted to a small diameter portion on the back side (atmosphere side) of the stationary ring 220 of the in-machine non-contact seal 200. It is fixed to the step portion 222. As a result, the rubber spring 240 maintains the stationary ring 220 concentrically with the rotary shaft 2 in the radial direction and movably in the axial direction.

  As described above, the stationary ring 220 of the in-machine non-contact seal 200 is non-rotatably engaged with the second seal housing 162 by the knock pin 253 and is pressed in the direction of the rotary ring 210 by the compression spring 251, so that the first seal The housing 161 is disposed in the inner peripheral hollow portion. Further, as described above, the inner peripheral side end portion of the rubber spring 240 is fixed to the step portion 222 on the outer peripheral surface of the stationary ring 220 on the outside of the machine, whereby the stationary ring 220 is attached to the first seal housing 161. And is held movably in the axial direction in a sealed state.

The material of the stationary ring 220 of the in-machine non-contact seal 200 may be a carbon material. However, in this embodiment, the stationary ring 220 is made of a hard material such as SiC, cemented carbide, or ceramic coating material similar to the rotating ring 210. It is.
Note that the seal surface 200S of the in-machine non-contact seal 200 is substantially perpendicular to the axis of the rotary shaft 2, but may be an inclined surface if necessary.

On the inner peripheral surface of the third seal housing 163, a retainer portion 191 is formed radially inward. The retainer portion 191 is arranged inside the machine of the fixing flange portion 151 of the sleeve collar 147 installed on the rotating shaft 2.
The retainer portion 191 has a plurality of recesses 193 that open toward the inner side of the axial direction machine. The plurality of recesses 193 are equally arranged in the ring-shaped retainer portion 191. The recess 193 holds the proximal end of the compression spring 351. The tip of the compression spring 351 contacts the back surface (atmosphere side end surface) of the stationary ring 320 of the outboard contact seal 300 and presses the stationary ring 320 inward in the axial direction machine. As a result, the stationary ring 320 of the outboard contact seal 300 is pressed against the rotating ring 310 of the outboard contact seal 300.

A knock pin 353 is installed on the outer peripheral portion of the retainer portion 191 of the third seal housing 163 toward the inner side in the axial direction. The knock pin 353 is engaged with a notch 332 formed on the back surface (atmosphere side end surface) of the stationary ring 320 of the outboard contact seal 300.
In addition, an O-ring groove 341 is formed on the contact surface with the retainer portion 191 of the third seal housing 163 on the inner peripheral side of the stationary ring 320 of the outboard contact seal 300, and the O-ring 343 is mounted. The gap between the retainer portion 191 and the stationary ring 320 of the third seal housing 163 is sealed.

With such a configuration, the stationary ring 320 of the outboard contact seal 300 is movable in the axial direction via the O-ring 343 and is locked in a relatively non-rotatable manner with respect to the third seal housing 163. Retained.
The material of the O-ring 343 may be the same material as that of the O-rings 171 and 175, for example.
Further, the material of the stationary ring 320 of the outboard contact seal 300 is made of, for example, carbon having excellent lubricity in this embodiment.

As shown in FIGS. 4A and 4B, the seal ring 321 of the stationary ring 320 penetrates the first groove 322 formed as a simple recess and the back surface of the seal surface 321 of the stationary ring 320. And a second groove 323 in which a pore 324 is formed. In other words, the first groove 322 is a groove that is not connected to the back surface of the stationary ring 320.
The fine hole 324 formed in the second groove 323 is a small diameter tube having a diameter of 3 mm or less, and is fixed to the bottom of the second groove 323 formed on the sliding surface 321 side of the stationary ring 320 and the fixed groove 320. It penetrates the back surface of the ring 320.

  As shown in FIGS. 1 and 2, the outer peripheral side of the seal surface 300S (321) of the outside contact seal 300 is the intermediate chamber 400 of the seal device 10, and the inner peripheral side of the seal surface 300S (321) is the outside atmosphere space A. It becomes. As shown in the figure, the back side space of the stationary ring 320 communicates with the intermediate chamber 400. The pressure in the intermediate chamber 400 is higher than the atmospheric pressure outside the machine.

  In the stationary ring 320 having such a configuration, the pressure in the intermediate chamber 400 is introduced into the second groove 323 formed in the seal surface 321 through the pores 324, and the contact load between the stationary ring 320 and the rotating ring 310. It works to lower. This state always works as long as the pressure in the intermediate chamber 400 is higher than the atmospheric pressure regardless of whether or not the rotating shaft 2 is rotating. Therefore, the second groove 323 always acts on the pressure in the intermediate chamber 400. Acts as a static pressure groove that acts to reduce the contact load.

  On the other hand, the first groove 322 formed on the seal surface 321 of the stationary ring 320, that is, the groove 322 that does not communicate with the high-pressure space such as the intermediate chamber 400 (see FIG. 3) In addition, the dynamic pressure due to the relative sliding of the seal surface 300S by the fluid that has entered the groove acts to reduce the contact load between the stationary ring 320 and the rotating ring 310. Accordingly, the first groove 322 acts as a dynamic pressure groove that acts to reduce the contact load when the rotating shaft 2 rotates.

  Note that the number of the first grooves 322 and the second grooves 323, the length, the width, the inner diameter (outer diameter) of each of the first grooves 322 and the second grooves 323, and one second groove 323. The number of pores 324 and the like is set in an appropriate form depending on the pressure and pressure fluctuation of the intermediate chamber 400, the rotational speed of the rotary shaft 2, the required surface pressure of the seal surface 300S, wear performance, and the like.

In the sealing device 10 having such a configuration, the axial space between the housing 4 and the rotary shaft 2 is partitioned by the in-machine non-contact seal 200 and the out-of-machine contact seal 300, so that the in-machine non-contact seal 200 is partitioned. An intermediate chamber 400 is formed from the inner peripheral space of the seal surface 200S to the outer peripheral space of the seal surface 300S of the outboard contact seal 300.
An inert gas such as N ₂ gas is supplied to the intermediate chamber 400 from a buffer gas pressure supply port 167 formed in the third seal housing 163.

  Next, the configuration of the sealing device 10 on the inner side of the in-machine non-contact seal 200 will be described with reference to FIG.

  In the sealing device 10, the first partition wall 510 is installed on the machine inner side of the machine inner non-contact seal 200, and the second partition wall 530 is installed further on the machine inner side of the first partition wall 510. The first partition wall 510 and the second partition wall 530 pivot on an axial circumferential space between the inner peripheral surface of the housing 4 of the apparatus body and the outer peripheral surface of the rotary shaft 2 on the inner side of the inner contactless seal 200. An annular member that is divided in each direction. That is, by installing the first partition wall 510 and the second partition wall 530, a first gas chamber 410 is formed between the in-machine non-contact seal 200 and the first partition wall 510, and the first partition is formed. A second gas chamber 420 is formed between the wall 510 and the second partition wall 530.

A floating ring 520 and a floating ring 540 are mounted on inner peripheral portions of the first partition wall 510 and the second partition wall 530 via O-rings 511, 513, 531 and 533, respectively.
Each of the floating rings 520 and 540 is provided with a spiral groove in the inner peripheral portion thereof, and a member that gives directionality to the fluid so that the fluid flows in the direction of the second gas chamber 420 as the rotating shaft 2 rotates. It is. In other words, the floating ring 520 installed on the inner peripheral portion of the first partition wall 510 allows the fluid in the first gas chamber 410 to flow into the second gas chamber 420 as the rotary shaft 2 rotates. Form a flow. In addition, the floating ring 540 installed on the inner peripheral portion of the second partition wall 530 allows the fluid in the inboard space Q to flow into the second gas chamber 420 as the rotating shaft 2 rotates. Form.

  An exhaust port 421 is formed in the second gas chamber 420, and the fluid flowing into the second gas chamber 420 is exhausted and recovered to the outside. The exhaust from the exhaust port 421 may be forcibly exhausted by a pump or the like, or may be natural exhaust.

  In the sealing device 10, as described above, the buffer gas is pressurized and flowed into the intermediate chamber 400 via the buffer gas pressurization supply port 167, and fluid flows from the first gas chamber 410 to the second gas chamber 420. The direction of the fluid is given by the floating ring 520 so that the fluid flows, and the direction of the fluid is given by the floating ring 540 so that the fluid flows from the interior space Q to the second gas chamber 420. The gas flowing into the second gas chamber 420 is exhausted and recovered from the exhaust port 421.

  Under such a configuration, in the sealing device 10, the pressure (P4) in the intermediate chamber 400, the pressure (P3) in the first gas chamber 410, the pressure (P2) in the second gas chamber 420, and the space inside the machine. The pressure (P1) of Q decreases in the order of the intermediate chamber 400, the first gas chamber 410, the second gas chamber 420, and the interior space Q during normal operation, that is, P4> P3> P2. > P1 is adjusted.

  Specifically, the pressure of the sealed fluid (pressure in the machine interior space Q), the flow rate of the buffer gas leaking from the machine non-contact seal 200, or, in some cases, when the gas is discharged from the second gas chamber 420 When adjusting the pressure of the buffer gas flowing into the intermediate chamber 400 based on the flow path resistance and the performance of the floating rings 520 and 540, or when discharging the gas from the second gas chamber 420 if possible Selection and adjustment of the flow resistance and the performance of the floating rings 520 and 540 are performed.

As described above, in the sealing device 10 of the present embodiment, a non-contact seal is used as the machine inner seal 200, and the buffer gas flows from the intermediate chamber 400 to the machine inner side. The solution or the like can be properly sealed, and even when applied to, for example, a pulverizer or the like, particles having a small particle diameter can be prevented from entering the intermediate chamber 400. Even when the sealed fluid flows into the vicinity of the in-machine non-contact seal 200, the in-machine non-contact seal 200 can appropriately seal the sealed fluid.
Further, the non-contact seal has little wear and excellent durability, and even if the fluid to be sealed is a slurry liquid or the like, it is possible to provide a seal device 10 that is excellent in wear resistance and can be effectively sealed. .

Further, since the rubber spring 240 is used as the secondary seal of the in-machine non-contact seal 200 in the sealing device 10, even if the sealed fluid adheres to the secondary seal, its operability is not hindered. Good sealing characteristics can be obtained. Therefore, an appropriate sealing characteristic can be obtained even with a slurry or a highly tacky solution that easily adheres to a fluid.
Further, even if the sealed fluid reaches the inside of the in-machine non-contact seal 200, the operability of the rubber spring 240 is not affected at all and good sealing characteristics can be obtained.

  Further, in the sealing device 10, a double partition wall, a first partition wall 510 and a second partition wall 530, is installed inside the machine inner non-contact seal 200 and the first gas chamber is installed in the machine interior space. 410 and the second gas chamber 420 are formed, and the sealed fluid is difficult to reach the sealing surface 200S of the in-machine non-contact seal 200, and the sealed fluid can be properly sealed and durable. A good sealing device can be provided.

  Further, the pressure relationship of each space is as follows: the pressure in the intermediate chamber 400 (P4)> the pressure in the first gas chamber 410 (P2)> the pressure in the second gas chamber 420 (P3)> the pressure in the machine interior space Q (P4) ), The possibility that the fluid to be sealed such as slurry and high-viscosity fluid will contact the sealing surface 200S of the in-machine non-contact seal 200 is further reduced, and good sealing characteristics are increased. A durable sealing device that can be maintained can be provided.

  In addition to the fluid pressure relationship described above, the inner peripheral portions of the first partition wall 510 and the second partition wall 530 are connected to the second gas chamber 420 from the machine interior and the first gas chamber 410, respectively. Since the floating rings 520 and 540 that allow the fluid to flow are installed, the possibility that the sealed fluid reaches the sealing surface 200S of the in-machine non-contact seal 200 is further reduced, and the sealed fluid is appropriately sealed. It is possible to provide a highly durable sealing device.

  In addition, the second gas chamber 420 has an exhaust port 421, and the fluid flowing into the second gas chamber 420 is appropriately discharged. Further, it is possible to prevent the sealed fluid as a product from being diluted, or to prevent the performance of pulverization and dispersion from being deteriorated.

In addition, since a contact seal (dry contact seal) 300 is provided as an outboard (atmosphere side) seal, the buffer gas flowing into the intermediate chamber 400 can be sealed without leaking outside. Further, even if the in-machine non-contact seal 200 is damaged, the sealed fluid can be sealed without leaking to the outside.
In addition, the amount of buffer gas used can be greatly reduced as compared to the case of using a non-contact seal for both of the two seals.

  The above-described embodiments are described for facilitating understanding of the present invention, and do not limit the present invention. Each element disclosed in the present embodiment includes all design changes and equivalents belonging to the technical scope of the present invention, and various suitable modifications can be made.

For example, the configuration details of the above-described in-machine non-contact seal 200 and out-of-machine contact seal 300 may be arbitrarily changed.
In the above-described embodiment, the dynamic pressure generating groove 212 is formed in the rotating ring 210 in the in-machine non-contact seal 200. However, the dynamic pressure generating groove 212 may be formed in the stationary ring 220 or in both the rotating ring 210 and the stationary ring 220. It may be formed.
In addition, the shape of the dynamic pressure generating groove 212 is L-shaped in the above-described embodiment, but may be T-shaped or spiral-shaped.

  The present invention can be applied to any device as long as it is a rotating machine that processes any fluid in a container (case, housing). In particular, it is effective for a machine that processes a high-concentration slurry liquid or a high-viscosity solution, and is effective when applied to, for example, a pulverizer or a disperser. Moreover, it can be suitably applied to a submersible pump or the like. As an industrial field, it can be used in any industry that uses the above-described machines, and can be effectively used in, for example, the construction industry, civil engineering industry, human waste processing industry, mining industry, semiconductor manufacturing industry, and the like.

DESCRIPTION OF SYMBOLS 2 ... Rotary shaft 4 ... Housing 5 ... Hole 10 ... Sealing device 111 ... 1st sleeve 131 ... 2nd sleeve 113, 133 ... Flange 115, 123, 135, 139 ... O-ring groove | channel 117, 125, 137, 141 ... O-ring 119 ... Labyrinth seal ring 127, 143 ... Key groove 129, 145 ... Key 147 ... Sleeve collar 149 ... Set screw 151 ... Fixing flange 161 ... First seal housing 162 ... Second seal housing 163 ... Third Seal housing 165 ... Bolt 167 ... Buffer gas pressure supply port 169, 173, 177 ... O-ring groove 171, 175, 179 ... O-ring 181, 191 ... Retainer part 183, 193 ... Recess 185 ... Rubber spring installation part 200 ... Machine Inner non-contact seal 200S ... Roll surface 210 ... Rotating ring
211 ... Seal surface
212 ... Dynamic pressure generating groove
213 ... Radial part
214 ... Circumferential part
215 ... Barrier layer 220 ... Static ring
221 ... Seal surface
222 ... Step part
223 ... Notch 240 ... Rubber spring 251 ... Compression spring 253 ... Knock pin 300 ... Outer side contact seal 300S ... Sliding seal surface 310 ... Rotating ring
311 ... Sealing surface 320 ... Stationary ring
321 ... Seal surface
322 ... first groove
323 ... second groove
324 ... pore
332 ... Notch 341 ... O-ring groove 343 ... O-ring 351 ... Compression spring 353 ... Knock pin 400 ... Intermediate chamber 410 ... First gas chamber 420 ... Second gas chamber 421 ... Exhaust port 510 ... First partition wall 520 ... Floating ring 530 ... Second partition wall 540 ... Floating ring

Claims (4)

A sealing device that seals between a hole of a housing and a rotating shaft that passes through the hole of the housing,
A rotating ring that is installed on the rotating shaft and has a sealing surface at one end in the axial direction of the rotating shaft; and a stationary ring that has a sealing surface that is installed on the housing and is disposed opposite to the sealing surface of the rotating ring. A dynamic pressure generating groove is formed on one or both of the sealing surface of the rotating ring and the sealing surface of the stationary ring, and the sealing surface of the rotating ring is rotated by rotation of the rotating shaft. An in-machine non-contact seal in which the sealing surface of the stationary ring is in a non-contact state with each other;
A rotary ring installed on the outer side of the machine non-contact seal, installed on the rotary shaft and having a seal surface at one end in the axial direction of the rotary shaft, and the seal of the rotary ring installed on the housing A stationary ring having a sealing surface disposed opposite to the surface, an outboard contact seal in which the sealing surface of the rotating ring and the sealing surface of the stationary ring slide closely
An intermediate chamber between the non-contact seal and the contact seal, in which a buffer gas flows;
A first gas chamber is installed on the inner side of the in-machine non-contact seal inside the housing and divides the space around the rotation shaft in the axial direction to form a first gas chamber with the in-machine non-contact seal. Partition walls,
A second gas chamber is installed further inside the housing than the first partition wall inside the housing, and the second gas chamber is formed between the first partition wall and the space surrounding the rotating shaft in the axial direction. Two partition walls,
An exhaust port is formed in the second gas chamber ,
The pressures of the intermediate chamber, the first gas chamber, the second gas chamber, and the interior space are the pressure of the intermediate chamber, the pressure of the first gas chamber, the pressure of the second gas chamber, A sealing device configured to decrease in order of pressure in an in-machine space . A small gap is formed between the outer peripheral surface of the rotary shaft and an inner peripheral portion of one or both of the first partition wall and the second partition wall to form a fluid, and fluid is transferred to the second gas chamber. The sealing device according to claim 1 , further comprising a floating ring that flows in a direction. The contact seal is not in communication with the outside formed in the recess in a predetermined range along the circumferential direction on one or both of the seal surface of the rotating ring and the seal surface of the stationary ring. And at least one second groove that is formed in the recess in a predetermined range along the circumferential direction and communicates with the outside so that pressure can be introduced from the outside. The sealing device according to claim 1 , wherein the sealing device is characterized by the following. The sealing device according to claim 1 , wherein the non-contact seal includes a rubber spring as a secondary seal.

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