JP2012241833A - Shaft seal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shaft seal device improved in maintenance properties.SOLUTION: The shaft seal device S for sealing an annular gap between a rotating shaft 630 and a shaft hole 621 of a housing 620 includes: a first seal structural part 100 provided on a sealed area side V; and a second seal structural part 200 provided on the atmospheric side A opposite to the sealed area relative to the first seal structural part 100. The first seal structural part 100 includes a first rotating ring 120 attachable to and detachable from the rotating shaft 630 from the outer circumferential surface side of the rotating shaft 630. A seal cover 300 is provided on the outer circumferential side of the first seal structural part 100 and second seal structural part 200. The seal cover is constituted to be slidable in the axial direction, and can form a sealed space R between the first seal structural part 100 and the second seal structural part 200 by moving to the sealed area side V and expose the first rotating ring 120 by moving to the atmospheric side A.

Description

  The present invention relates to a shaft seal device that seals an annular gap between a rotating shaft and a shaft hole of a housing.

  In a shaft seal device, when sealing a sealing region, a technique is known in which seal structure portions are provided at two locations in the axial direction. In such a technique, when the atmosphere-side seal structure portion is a mechanical seal, generally, the stationary ring constituting the mechanical seal has a plurality of members with respect to the casing of the apparatus main body on the sealed region side. The structure fixed via is adopted. For this reason, if the parts that make up the seal structure on the sealed area side are consumable parts, it takes a lot of work to replace the consumable parts, such as having to disassemble multiple members to replace the consumable parts. ing.

Japanese Patent No. 4283296

  An object of the present invention is to provide a shaft seal device with improved maintainability.

  The present invention employs the following means in order to solve the above problems.

That is, the shaft seal device of the present invention is
In the shaft seal device that seals the annular gap between the rotation shaft and the shaft hole of the housing,
A first seal structure provided on the sealing region side;
A second seal structure provided on the atmosphere side opposite to the sealing region with respect to the first seal structure;
A shaft seal device comprising:
The first seal structure includes a rotary seal that is detachably attached to the rotary shaft from the outer peripheral surface side of the rotary shaft,
The outer peripheral sides of the first seal structure portion and the second seal structure portion are configured to be slidable in the axial direction, and moved between the first seal structure portion and the second seal structure portion by moving to the sealing region side. A seal cover is provided, which can form a sealed space and can be moved to the atmosphere side to expose the rotary seal.

  According to the present invention, the rotary seal can be exposed by moving the seal cover to the atmosphere side. And since a rotation seal is detachable with respect to this rotating shaft from the outer peripheral surface side of a rotating shaft, a rotating seal can be replaced | exchanged easily.

The second seal structure is
A mechanical ring having a fixed ring fixed to the housing side through the seal cover and a rotary ring fixed to the rotating shaft, the end surfaces of the fixed ring and the rotating ring sliding with each other in the axial direction. It should be a seal. The “fixed ring” and the “rotating ring” in the present invention include a case of being constituted by a plurality of members as well as a case of being constituted by one member.

And, in a state where the rotating shaft is not rotated, a positioning member for positioning the stationary ring and the rotating ring is provided,
It is preferable that the seal cover can be slid by placing the stationary ring with respect to the rotating shaft via the rotating ring by the positioning member.

  As described above, even when the second seal structure is a mechanical seal, the seal cover is slid by moving the fixed ring with respect to the rotating shaft via the rotating ring by the positioning member. It becomes possible.

  As described above, according to the present invention, maintainability can be improved.

FIG. 1 is a schematic cross-sectional view of the entire shaft seal device according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view of the first seal structure according to the embodiment of the present invention. FIG. 3 is a schematic cross-sectional view of the second seal structure portion according to the embodiment of the present invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be exemplarily described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. .

(Example)
A shaft seal device according to an embodiment of the present invention will be described with reference to FIGS. The shaft seal device according to the present embodiment is used to seal an annular gap between the rotary shaft and a shaft hole provided in the housing on the machine body side.

<Whole seal device>
In particular, the configuration of the entire shaft seal device according to the embodiment of the present invention will be described with reference to FIG.

  An opening 611 is provided in the casing 610 of the rotating device 600, and an annular housing 620 is attached to the opening 611. The rotating shaft 630 is inserted into the shaft hole 621 in the housing 620. A sleeve 650 is fixed to the rotating shaft 630 while being positioned by a set screw 651. A space between the inner peripheral surface of the sleeve 650 and the outer peripheral surface of the rotary shaft 630 is sealed with an O-ring O. The inside of the housing 610 is a sealed region, and a sealed fluid is sealed.

  The shaft seal device S according to the present embodiment is provided on the first seal structure portion 100 provided on the sealing region side V and on the atmosphere side A opposite to the sealing region with respect to the first seal structure portion 100. 2nd seal structure part 200 is provided. Further, the shaft seal device S is provided with a seal cover 300 for forming a sealed space R between the first seal structure portion 100 and the second seal structure portion 200. The seal cover 300 has hexagon socket bolts on the outer peripheral side of the first fixed ring 110 provided in the first seal structure part 100 and on the outer peripheral side of the second fixed ring 210 provided in the second seal structure part 200, respectively. 310 and a set screw 320. With the configuration as described above, it is possible to suppress a decrease in the sealing performance of the first seal structure portion 100 by suppressing leakage of the sealed fluid by the second seal structure portion 200.

<First seal structure>
In particular, with reference to FIG. 2, the first seal structure portion 100 according to the present embodiment will be described in more detail.

  The first seal structure 100 has a so-called end face seal structure. Specifically, the first seal structure unit 100 includes a first fixed ring 110 fixed to the housing 620 and a first rotary ring (rotary seal) 120 fixed to the rotation shaft 630. Yes. The first fixed ring 110 is directly fixed to the housing 620. The first fixed ring 110 and the housing 620 and the first fixed ring 110 and the seal cover 300 are sealed by O-rings O, respectively.

  The first rotating ring 120 is made of a resin material such as a filled fluororesin or polyamide resin, or a deformable polymer material such as rubber, and has a cutting portion (joint) at one place in the circumferential direction. Is provided. Accordingly, the first rotating ring 120 is attached to and detached from the rotating shaft 630 from the outer peripheral surface side of the rotating shaft 630 by opening the both end portions through the cutting portion larger than the outer diameter of the sleeve 650. can do. The first rotating ring 120 has a symmetric structure having convex portions on both sides. Thereby, when one surface deteriorates by abrasion, it can be reused by attaching it in the inverted state, and the lifetime can be extended.

  In the present embodiment, the first rotary ring 120 is fastened and fixed to the sleeve 650 by the hose band 130 in a state where the first rotary ring 120 is disposed on the outer peripheral surface side of the sleeve 650. The first rotating ring 120 can be tightened by the hose band 130 by rotating the clamp 131 provided on the hose band 130. Further, when removing the first rotating ring 120, the hose band 130 may be removed after the clamp 131 is rotated in the reverse direction to loosen the hose band 130. The member for fastening the first rotating ring 120 is not limited to the hose band 130, and for example, a garter spring may be employed.

  A seal portion is formed between the end face on the atmosphere side A of the first fixed ring 110 and the end face on the sealed region side V of the first rotating ring 120. Here, a so-called mechanical seal structure that performs sealing by sliding the end surface on the atmosphere side A in the first stationary ring 110 and the end surface on the sealing region side V in the first rotating ring 120 may be employed, You may employ | adopt the non-contact seal structure which provides a micro clearance gap between these end surfaces.

<Second seal structure>
In particular, the second seal structure 200 according to the present embodiment will be described in more detail with reference to FIG.

  The second seal structure 200 is a so-called mechanical seal. More specifically, the second seal structure 200 includes a second fixed ring 210 that is fixed to the housing 620 and a second rotary ring 220 that is fixed to the rotating shaft 630. The second fixed ring 210 is indirectly fixed to the housing 620 via the seal cover 300 or the like. The second rotating ring 220 is indirectly fixed to the rotating shaft 630 via the sleeve 650.

The second fixed ring 210 includes an annular flange 211 fixed to the inner peripheral surface of the seal cover 300 by a set screw 320, an annular retainer 212 configured to be movable in the axial direction with respect to the flange 211, and the retainer 212. And an annular seal ring 213 fixed to. The outer peripheral surface of the flange 211 and the inner peripheral surface of the seal cover 300 are sealed with an O-ring O. The retainer 212 is an annular member having a substantially L-shaped cross section, and the drive pin 211a fixed to the flange 211 is inserted into the through hole 212a provided in the disk portion. , And is configured to be movable in the axial direction along the drive pin 211a. Further, a mounting hole 211b is provided on the end surface of the flange 211 on the atmosphere side, and a spring 214 is mounted in the mounting hole 211b (see FIG. 1). By this spring 214, the retainer 212 is pressed in the right direction in the figure. Note that an O-ring O seals between the outer peripheral surface of the cylindrical portion of the retainer 212 and the inner peripheral surface of the flange 211.

  The second rotating ring 220 includes an annular collar 221 that is fixed to the sleeve 650 and an annular mating ring 222 that is fixed while being engaged with the collar 221. The mating ring 222 has a substantially L-shaped cross section, and the end surface on the atmosphere side A of the disk portion and the inner peripheral surface of the cylindrical portion are in close contact with the end surface and outer peripheral surface of the sealing region side V in the collar 221, respectively. It is configured as follows. Further, a notch 222a is provided in the disk portion of the mating ring 222, and a drive pin 221a fixed to the collar 221 is inserted into the notch 222a. A cap 221b for preventing the mating ring 222 from being damaged is attached to the tip of the drive pin 221a. Further, an O-ring O seals between the inner peripheral surface of the collar 221 and the outer peripheral surface of the sleeve 650, and between the outer peripheral surface of the collar 221 and the inner peripheral surface of the cylindrical portion of the mating ring 222. .

  With the above-described configuration, the collar 221 rotates with the rotation of the rotating shaft 630, the rotational torque is transmitted to the mating ring 222 via the drive pin 221a, and the mating ring 222 also rotates. At this time, the seal ring 213 provided on the second fixed ring 210 and the mating ring 222 provided on the second rotating ring 220 slide. As described above, when the retainer 212 is pressed rightward in the drawing by the spring 214, the seal ring 213 fixed to the retainer 212 is pressed against the mating ring 222, and the sliding state is stable. Maintained. In order to maintain the sliding performance, the sliding surfaces of the seal ring 213 and the mating ring 222 are each provided with a known coating excellent in self-lubricity.

  In this embodiment, a sealing device 230 is provided at the end of the second stationary ring 210 on the sealing region side V. The sealing device 230 includes a case 231 and a plate 232 that are fixed to the flange 211 by bolts 234, and a sealing device main body 233 that is fixed by the case 231 and the plate 232. The sealing device main body 233 may employ a known seal that exhibits a sealing property in a state of sliding with respect to the outer peripheral surface of the sleeve 650. Thus, by providing the sealing device 230 at the end of the second stationary ring 210 on the sealing region side V, the space region where the sliding portion between the seal ring 213 and the mating ring 222 exists, the sealed space R, and Can be separated. Thereby, even if the sealed fluid leaks into the sealed space R, the sealed fluid can be prevented from entering the sliding portion. Note that the sealing device main body 233 is also provided with a cutting portion (abutment) at one place in consideration of workability at the time of component replacement, similarly to the first rotary ring 120.

Further, as described above, the mating ring 222 provided on the second rotating ring 220 is pressed by the seal ring 213 provided on the second fixed ring 210. For this reason, when fixing the second rotating ring 220 to the sleeve 650, a jig 240 as a positioning member is used. That is, when the second rotating ring 220 is attached, the jig body 241 is fixed to the flange 211 and the collar 221 by the set screws 242 and 243, respectively. That is, the second rotating ring 220 is temporarily fixed to the second fixed ring 210. In this state, the collar 221 in the second rotating ring 220 is fixed to the sleeve 650 by the set screw 223 (see FIG. 1). Thereafter, the set screws 242 and 243 are loosened and the jig 240 is removed. The jig body 241 has a split structure in consideration of assembly and disassembly workability.

(Seal cover)
In particular, the seal cover 300 will be described in detail with reference to FIGS. 1 and 3. The seal cover 300 according to the present embodiment is formed of a cylindrical member, and an outward flange portion 301 is provided at an end portion (the left end portion in FIG. 1). Further, a through hole 301 a is formed in the outward flange portion 301.

  A guide shaft 400 extending in parallel with the axis of the rotation shaft 630 is fixed to the housing 620. The guide shaft 400 is configured to be inserted through a through hole 110 a provided in the first fixed ring 110.

  The seal cover 300 is arranged so that the guide shaft 400 fixed to the housing 620 is inserted into the through hole 301 a provided in the seal cover 300. Thereby, the seal cover 300 is slidable in a direction (axial direction) parallel to the axis of the rotation shaft 630 by being guided by the guide shaft 400. By moving the seal cover 300 to the sealed region side V, the sealed space R can be formed between the first seal structure portion 100 and the second seal structure portion 200. The sealed space R is formed by fixing the seal cover 300 to the first fixed ring 110 and the second fixed ring 210 with the hexagon socket bolt 310 and the set screw 320 in a state where the seal cover 300 is moved to the sealed region side V, respectively. Is done. Further, by moving the seal cover 300 to the atmosphere side A (moving in the direction of the arrow in FIG. 1), the space between the first seal structure part 100 and the second seal structure part 200 is opened, and the first rotating ring. 120 is exposed.

  Here, in order to make the seal cover 300 slidable stably, it is necessary to prevent the second fixed ring 210 from moving when the seal cover 300 is slid. That is, as described above, the second fixed ring 210 is indirectly fixed to the housing 620 via the seal cover 300 or the like. Therefore, when the seal cover 300 is movable with respect to the housing 620, the second stationary ring 210 is not supported by any member, and thus is movable with respect to the housing 620 and the rotating shaft 630. It becomes a state. As described above, the seal cover 300 cannot be stably slid in a state where the second fixed ring 210 can freely move.

  Therefore, in the present embodiment, when the seal cover 300 is slid, the jig 240 described above is used. That is, the second fixed ring 210 and the second rotary ring 220 are fixed and positioned by the jig 240 without rotating the rotary shaft 630. As a result, the second fixed ring 210 is positioned with respect to the rotation shaft 630 via the second rotation ring 220 and the sleeve 650. That is, the second fixed ring 210 is positioned in a state of being centered with respect to the rotation shaft 630. Accordingly, the seal cover 300 can be slid stably.

<Excellent point of shaft seal device according to this embodiment>
According to the shaft seal device S according to the present embodiment, the first rotary ring 120 as the rotary seal can be exposed by moving the seal cover 300 to the atmosphere side A. Thereby, the 1st rotation ring 120 can be exchanged easily. Moreover, since the structure which exposes the 1st rotation ring 120 is employ | adopted by sliding the seal cover 300, a structure can be simplified. In other words, a configuration in which the first rotating ring 120 is exposed by disassembling the case by configuring the case with a plurality of members and disassembling can be considered. The structure can be simplified.

  In this embodiment, since the fluid to be sealed is sealed on the sealed region side V, the space between the end surface on the atmosphere side A in the first stationary ring 110 and the end surface on the sealed region side V in the first rotating ring 120 is. The fluid to be sealed may enter into. In this case, the end surface on the sealing region side V in the first rotating ring 120 is worn, and therefore, consumption is severe as compared with the constituent members of the second seal structure 200, and maintenance such as replacement with a new one is required. .

  Here, the second seal structure 200 provided on the atmosphere side A with respect to the first rotating ring 120 to be exchanged includes a stationary ring (second stationary ring 210) and a rotating ring (second rotating ring 220). It is a mechanical seal provided. The second fixed ring 210 employs a configuration that is fixed to the seal cover 300 during use. However, when exchanging the first rotating ring 120, as described above, the jig 240 is used to position the second fixed ring 210 with respect to the rotating shaft 630 via the second rotating ring 220 and the like. The seal cover 300 can be stably slid. Accordingly, the first rotary ring 120 on the sealed region side V can be easily replaced even though the second seal structure 200 on the atmosphere side A is a mechanical seal. Further, since the replacement operation of the first rotating ring 120 can be performed by moving the seal cover 300 with the second seal structure 200 as it is, the second seal structure 200 may be adversely affected. Absent.

DESCRIPTION OF SYMBOLS 100 1st seal structure part 110 1st fixed ring 110a Through-hole 120 1st rotation ring 130 Hose band 131 Clamp 200 2nd seal structure part 210 2nd fixed ring 211 Flange 211a Drive pin 211b Mounting hole 212 Retainer 212a Through-hole 213 Seal Ring 214 Spring 220 Second rotating ring 221 Color 221a Drive pin 221b Cap 222 Mating ring 223 Set screw 230 Sealing device 231 Case 232 Plate 233 Sealing device main body 234 Bolt 240 Jig 241 Jig main body 242 and 243 Set screw 300 Seal cover 301 outward flange portion 301a through hole 310 hexagon socket bolt 320 set screw 400 guide shaft 600 rotating device 610 housing 6 1 opening 620 housing 621 a shaft hole 630 rotating shaft 650 sleeve 651 setscrew O O-ring R sealed space S shaft sealing device

Claims (3)

In the shaft seal device that seals the annular gap between the rotation shaft and the shaft hole of the housing,
A first seal structure provided on the sealing region side;
A second seal structure provided on the atmosphere side opposite to the sealing region with respect to the first seal structure;
A shaft seal device comprising:
The first seal structure includes a rotary seal that is detachably attached to the rotary shaft from the outer peripheral surface side of the rotary shaft,
The outer peripheral sides of the first seal structure portion and the second seal structure portion are configured to be slidable in the axial direction, and moved between the first seal structure portion and the second seal structure portion by moving to the sealing region side. A shaft seal device comprising: a seal cover capable of exposing the rotary seal by forming a sealed space in the air and moving the space to the atmosphere side. The second seal structure is
A mechanical ring having a fixed ring fixed to the housing side through the seal cover and a rotary ring fixed to the rotating shaft, the axial ends of the fixed ring and the rotating ring slide. The shaft sealing device according to claim 1, wherein the shaft sealing device is a seal. A positioning member that positions the stationary ring and the rotating ring in a state where the rotating shaft is not rotated,
2. The seal cover can be slid by placing the stationary ring with respect to the rotating shaft via the rotating ring by the positioning member. Or the shaft seal apparatus of 2.

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