JP7074648B2 - mechanical seal - Google Patents

Description

The present invention relates to a mechanical seal that seals a rotating shaft.

A mechanical seal that seals between the fixed side structure and the rotating shaft is known when the rotating shaft is mounted so as to be relatively rotatable with respect to the fixed side structure (housing) such as a water pump and a stirrer. ..

For example, the mechanical seal shown in Patent Document 1 is applied to a water pump, and has a static sealing ring, a bellows outerly fitted to the static sealing ring, and a static sealing ring arranged on the outer diameter side of the bellows. It is composed of a stationary side element having a wave spring (urging means) for urging the rotary sealing ring side and a rotating side element having a rotary sealing ring, and is outside the static sealing ring and the rotary sealing ring when the water pump is driven. The sealed fluid is sealed by using the pressure of the sealed fluid such as water guided to the diameter side or LLC (Long Life Pump).

Japanese Patent No. 50099909 (Page 2, Fig. 8)

In the mechanical seal shown in Patent Document 1, even if the pressure of the fluid to be sealed is weakened, the static sealing ring and the rotary sealing ring can be kept in close contact with each other by the urging force of the wave spring. When such a mechanical seal is used for general purposes, the wave spring may be clogged or corroded when the fluid to be sealed is a high-concentration slurry or corrosive.

The present invention has been made focusing on such a problem, and an object of the present invention is to provide a highly versatile mechanical seal that can be used without selecting a fluid to be sealed.

In order to solve the above problems, the mechanical seal of the present invention is used.
A static side element having a static sealing ring and attached to a housing, a rotating side element having a rotating sealing ring and attached to a rotating shaft, and an urging force for urging the static sealing ring and the rotating sealing ring in opposite directions. A mechanical seal with means and
The stationary sealing ring or the rotary sealing ring has a partitioning means for partitioning the back surface side into an inner diameter side and an outer diameter side in a sealed manner, and the urging means is provided on the inner diameter side and the outer diameter side of the partitioning means, respectively. It is characterized by having an installation space that can be installed.
According to this feature, one of the installation spaces provided on the inner diameter side and the outer diameter side of the partition means can be appropriately selected to arrange the urging means, so that a highly versatile mechanical seal can be provided. can. For example, the urging means can be arranged by selecting an installation space that is not affected by the sealed fluid from the installation spaces provided on the inner diameter side and the outer diameter side of the partition means.

Preferably, the stationary element has a case attached to the housing, the partitioning means is arranged so as to be axially movable relative to the case, and the installation space is the same as the case. It is formed between the partition means and the partition means.
According to this, since the case and the partitioning means can move relative to each other in the axial direction, it is easy to assemble the urging means.

Preferably, the partitioning means has a tubular member for partitioning the static sealing ring and the case, and an annular secondary seal, wherein the tubular member is attached to the case by the secondary seal. It is connected in a sealed shape and can move relative to the axial direction.
According to this, since the case and the partitioning means can move relative to each other in the axial direction, assembly is easy.

Preferably, the tubular member is formed with a support portion that holds the urging means in the radial direction.
According to this, since the cylindrical member can hold the urging means in a state of being abutted in the radial direction, the urging means can be accurately positioned in the installation space.

Preferably, the case is formed with a support portion that holds the urging means in the radial direction.
According to this, since the case can hold the urging means in a state of being abutted in the radial direction, the urging means can be accurately positioned in the installation space.

Preferably, the rotating side element and the stationary side element are formed into a cartridge in which movement in a direction away from each other in the axial direction is restricted.
According to this, the mechanical seal can be easily attached to the housing and the rotating shaft.

It is a side sectional view which shows the mechanical seal in Example 1 of this invention. (A) to (c) are side sectional views showing an assembly procedure of a mechanical seal. (A) and (b) are side sectional views showing an assembly procedure of a mechanical seal following FIG. 2. FIG. 3 is a side sectional view showing a mechanical seal in which the arrangement position of the urging means is changed from FIG. 1. It is a side sectional view which shows the mechanical seal in Example 2 of this invention. It is a side sectional view which shows the mechanical seal in Example 3 of this invention. It is a side sectional view which shows the mechanical seal in Example 4 of this invention. It is a side sectional view which shows the mechanical seal in Example 5 of this invention. It is a side sectional view which shows the mechanical seal in Example 6 of this invention.

The mechanical seal according to the first embodiment will be described with reference to FIGS. 1 to 4.

In this embodiment, the back surface of the rotary sealing ring and the static sealing ring is an end surface of the rotary sealing ring and the static sealing ring located on the opposite side of the sliding surface.

As shown in FIG. 1, the mechanical seal 10A according to the embodiment of the present invention is provided between the housing 3 of a rotating machine such as a pump or a stirrer and the rotating shaft 2 inserted through the shaft hole H of the housing 3. The inside of the housing 3 is divided into the sealed fluid side L1 which is the outer diameter side of the mechanical seal 10A and the atmospheric side A1 which is the inner diameter side of the mechanical seal 10A, and the space between the housing 3 and the rotating shaft 2 is divided. Is used as a so-called inside type to prevent the sealed fluid inside the housing 3 from leaking to the outside.

The mechanical seal 10A is mainly composed of a rotating side element 20 attached to the rotating shaft 2 and a stationary side element 30 attached to the housing 3, and the rotating side element 20 and the stationary side element 30 are made into a cartridge. It was done.

First, the rotation side element 20 will be described. The rotating side element 20 includes a collar 21 fixed to the rotating shaft 2 with a set screw, a sleeve 22 arranged on the inner diameter side of the collar 21, a gasket 24 fitted inside the inner diameter side of the sleeve 22, and a gasket 24. It is mainly composed of a rotary sealing ring 25 fitted inside on the inner diameter side, and an O-ring 26 arranged between the collar 21, the sleeve 22, and the rotary shaft 2.

The collar 21 is formed in a stepped cylindrical shape, and a concave portion 21a opened to the right side of the paper surface and the inner diameter side at a part of the end portion on the right side of the paper surface on the housing 3 side is peripherally formed on the peripheral wall of the collar 21. It is formed in 6 equal parts in the direction. The recessed portion 21a may be formed in addition to the 6 equal arrangement.

The sleeve 22 is formed in a lateral J-shaped annular shape in a cross-sectional view, and has an outer diameter side cylindrical portion 22b extending axially on the outer diameter side and an inner diameter side tubular portion 22c extending axially on the inner diameter side. is doing. Further, in the outer diameter side tubular portion 22b, claw portions 22a extending in the outer diameter direction are formed at the right end of the paper surface in a six-equal arrangement in the circumferential direction, and each claw portion 22a is a concave portion of the collar 21. It is locked to the setting portion 21a. Further, the inner diameter side cylindrical portion 22c is formed with an annular flange portion 22d extending in the outer diameter direction substantially orthogonal to the end portion on the right side of the paper surface. The claw portion 22a may be formed in a manner other than the 6 equal arrangement.

The gasket 24 is formed in a laterally L-shaped annular shape in cross-sectional view. The rotary sealing ring 25 is formed in an annular shape having a rectangular cross section.

Next, the rest side element 30 will be described. The stationary side element 30 is internally fitted in the case 31 inserted into the shaft hole H of the housing 3, the middle holder 32 as a cylindrical member arranged on the inner diameter side of the case 31, and the inner diameter side of the middle holder 32. An inner holder 33 as a cylindrical member, a gasket 34 internally fitted on the inner diameter side of the inner holder 33, a static sealing ring 35 internally fitted on the inner diameter side of the gasket 34, a case 31 and a middle holder 32. An O-ring 36 and a spacer 37 arranged between the wave spring 38A as a urging means arranged between the case 31 and the inner holder 33, and a seat packing 39 interposed between the housing 3 and the case 31. It is mainly composed of and.

The case 31 is formed in an annular shape, and is a U-shaped portion that opens to the rotation side element 20 side substantially orthogonal to the inner diameter side end portion of the flange portion 31a extending in the radial direction and the inner diameter side end portion of the flange portion 31a in order from the outer diameter side. 31b, the wall-shaped portion 31c extending in the inner diameter direction substantially orthogonal to the inner diameter side of the U-shaped portion 31b and the left end portion of the paper surface, and substantially orthogonal to the inner diameter side end portion of the wall-shaped portion 31c, the left side of the paper surface in the axial direction. It has an inner diameter side tubular portion 31d extending to the inside.

Further, in the inner diameter side cylindrical portion 31d, concave portions 31e that open to the left side of the paper surface are formed at the left end portion of the paper surface in a six-equal arrangement in the circumferential direction. The concave portion 31e may be formed in a configuration other than the six equal parts.

The middle holder 32 is formed in a cylindrical shape having two steps, and is substantially attached to the outer diameter side tubular portion 32a extending in the axial direction and the outer diameter side tubular portion 32a on the right end of the paper surface in order from the outer diameter side. An outer diameter side wall portion 32b extending orthogonally in the inner diameter direction, a central cylindrical portion 32c extending substantially orthogonal to the inner diameter side end portion of the outer diameter side wall shape portion 32b and extending to the right side of the axial paper surface, and a central tubular portion 32c. An inner diameter side wall 32d extending in the inner diameter direction substantially orthogonal to the right end of the paper surface, and an inner diameter side cylindrical portion 32e extending substantially orthogonal to the inner diameter side end of the inner diameter side wall 32d extending to the right side of the paper surface in the axial direction. Have.

Further, the inner diameter of the inner diameter side cylindrical portion 32e of the middle holder 32 is substantially the same as the outer diameter of the inner diameter side cylindrical portion 31b2 of the U-shaped portion 31b of the case 31.

The inner holder 33 is formed in an L-shape downward in cross section, and extends in the inner diameter direction substantially orthogonal to the cylindrical portion 33a extending in the axial direction and the right end portion of the tubular portion 33a in order from the outer diameter side. It has an existing wall-shaped portion 33b. Further, in the wall-shaped portion 33b, claw portions 33c extending to the left side of the paper surface are formed in a six-equal arrangement in the circumferential direction at the inner diameter side end portion, and each claw portion 33c is locked to the concave portion 31e of the case 31. There is. The claw portion 33c may be formed in a manner other than the 6 equal arrangement.

The gasket 34 is formed in an L-shaped annular shape facing downward in cross section. The static sealing ring 35 is formed in an annular shape having a rectangular cross-sectional view. The spacer 37 is formed in a rectangular annular shape with one end chamfered in a cross-sectional view. The seat packing 39 is formed in an annular shape having a flat cross-sectional view that is long in the axial direction.

Next, the assembly of the mechanical seal 10A will be described with reference to FIGS. 2 and 3. The assembly procedure described below may be changed as appropriate. As shown in FIG. 2A, the rotary side element 20 is assembled by internally fitting the gasket 24 and the rotary seal ring 25 on the inner diameter side of the sleeve 22.

Next, the assembly of the stationary side element 30 will be described. As shown in FIG. 2B, with the gasket 34 and the static sealing ring 35 fitted inside the inner diameter side of the inner holder 33, the inner holder 33 is press-fitted and fixed to the inner diameter side of the middle holder 32. After that, the O-ring 36 is externally fitted to the inner diameter side cylindrical portion 32e of the middle holder 32. A sealant is applied between the outer diameter side cylindrical portion 32a of the middle holder 32 and the tubular portion 33a of the inner holder 33 to improve the adhesion. Further, the middle holder 32 and the inner holder 33 may be welded and fixed.

As shown in FIG. 2C, the spacer 37 is inserted into the bottom portion of the case 31 in the U-shaped portion 31b. The outer diameter of the spacer 37 is substantially the same as the inner diameter of the outer diameter side cylindrical portion 31b1 of the U-shaped portion 31b, and the inner diameter of the spacer 37 is larger than the outer diameter of the inner diameter side cylindrical portion 31b2 of the U-shaped portion 31b. Since it is formed, a gap S is formed between the inner diameter side cylindrical portion of the U-shaped portion 31b and the spacer 37. The radial dimension of this gap S is longer than the plate thickness of the inner diameter side cylindrical portion 32e of the middle holder 32.

Further, the wave spring 38A is externally fitted to the inner diameter side cylindrical portion 31d of the case 31. The inner diameter side cylindrical portion 31d of the case 31 prevents the wave spring 38A from moving in the radial direction. That is, the inner diameter side cylindrical portion 31d is a support portion of the urging means in this embodiment.

By inserting the inner diameter side cylindrical portion 32e of the middle holder 32 into the gap S of the case 31 with reference to FIG. 3A, the case 31 and the middle holder 32 are temporarily fixed. At this time, a gap is formed between the central tubular portion 32c of the middle holder 32 and the outer diameter side tubular portion 31b1 of the U-shaped portion 31b of the case 31, and the slurry is unlikely to stagnate in this gap. The central cylindrical portion 32c of the middle holder 32 and the outer diameter side tubular portion 31b1 of the U-shaped portion 31b of the case 31 may be in contact with each other in the radial direction.

Next, referring to FIG. 3B, the inner diameter side tubular portion 22c of the sleeve 22 of the rotating side element 20 is inserted into the inner diameter side of the stationary side element 30, and the rotary sealing ring 25 and the static sealing ring 35 are inserted. In the butted state, the end portion on the right side of the paper surface of the inner diameter side cylindrical portion 22c indicated by the alternate long and short dash line is bent toward the outer diameter side to form the flange portion 22d. As a result, the relative movement of the sleeve 22 and the case 31 in the axial direction is restricted, the mechanical seal 10A is made into a cartridge, and the assembly is completed.

In the mechanical seal 10A, the case 31 and the middle holder 32 are hermetically connected via an O-ring 36, and the middle holder 32, the inner holder 33, and the gasket are connected between the back surface 35b of the static sealing ring 35 and the case 31. The inner diameter side and the outer diameter side are partitioned in a sealed manner by the 34 and the O-ring 36.

Further, on the inner diameter side of the middle holder 32 and the O ring 36, the annular inner diameter side installation space C1 defined by the wall-shaped portion 31c of the case 31, the inner diameter side tubular portion 31d, and the wall-shaped portion 33b of the inner holder 33. Since the wave spring 38A is arranged in the inner diameter side installation space C1, not only the wave spring 38A can be easily assembled, but also the wave spring 38A can be positioned accurately.

Further, in the mechanical seal 10A before being mounted on the housing 3 and the rotary shaft 2, the sliding surface 35a of the static sealing ring 35 is in close contact with the sliding surface 25a of the rotary sealing ring 25 due to the urging force of the wave spring 38A. , The wall-shaped portion 31c of the case 31 is in contact with the flange portion 22d of the sleeve 22.

Further, the mechanical seal 10A applies an external force from the axial direction to counteract the urging force of the wave spring 38A and to the bottom of the U-shaped portion 31b of the case 31 on the right side of the paper surface of the inner diameter side tubular portion 32e of the middle holder 32. It is possible to move until the ends of the spring come into contact with each other.

Next, the attachment of the mechanical seal 10A to the housing 3 and the rotating shaft 2 will be described with reference to FIG. First, the sleeve 22 is externally inserted into the rotating shaft 2, and the mechanical seal 10A is moved in the axial direction until the flange portion 31a of the case 31 comes into contact with the housing 3. At this time, the U-shaped portion 31b of the case 31 is press-fitted into the shaft hole H of the housing 3 in a sealed manner via the seat packing 39.

Next, by fixing the collar 21 to the rotating shaft 2 with the set screw in a state where the case 31 is further pushed to the right side of the axial paper surface by a predetermined dimension, the attachment of the mechanical seal 10A to the housing 3 and the rotating shaft 2 is completed. In this mounted state, the flange portion 22d of the sleeve 22 and the wall-shaped portion 31c of the case 31 are separated from each other, and the wave spring 38A is compressed by a predetermined dimension in the axial direction.

As described above, since the mechanical seal 10A is made into a cartridge, it can be easily attached to the housing 3 and the rotating shaft 2.

Further, in the mechanical seal 10A attached to the rotating shaft 2 and the housing 3, the sliding surfaces 25a and 35a of the rotary sealing ring 25 and the static sealing ring 35 are slidably brought into close contact with each other by utilizing the pressure of the sealed fluid. At the same time, the stationary portion is sealed by the gaskets 24, 34, the O-rings 26, 36, and the seat packing 39, which are secondary seals.

That is, the middle holder 32, the inner holder 33, the gasket 34 and the O-ring 36, and the seat packing 39 are located between the statically sealed ring 35 and the case 31 on the back surface 35b side of the statically sealed ring 35, and between the case 31 and the housing. It is a partitioning means in this embodiment that partitions the space between the three and the inner diameter side and the outer diameter side in a sealed manner, respectively.

Further, the sealed fluid flows into the balance line B1 indicated by the alternate long and short dash line and presses the middle holder 32 to the left side of the paper surface. The mechanical seal 10A is a so-called balance type in which the balance line B1 is arranged between the outer diameter side end portion and the inner diameter side end portion of the sliding surfaces 25a and 35a of the rotary sealing ring 25 and the static sealing ring 35 in the radial direction. The balance rate in this example is about 76%. The balance rate is not limited to about 76% and may be changed as appropriate. The same applies to the subsequent numerical values.

In addition to this, in the mechanical seal 10A, since the middle holder 32 can move relative to the case 31 in the axial direction, when the rotating shaft 2 tries to move relatively to the right side of the paper surface with respect to the housing 3, Within the range of the axial movement allowance between the case 31 and the middle holder 32, the stationary sealing ring 35 is pressed to the right side of the paper surface by the rotating sealing ring 25 driven by the rotating shaft 2 while the stationary sealing ring 35 is in close contact with the rotating sealing ring 25. It can be moved together with the middle holder 32.

Similarly, in the mechanical seal 10A, when the rotating shaft 2 tries to move to the left side of the paper surface relative to the housing 3, the pressure of the fluid to be sealed is within the range of the axial movement allowance between the sleeve 22 and the case 31. The static sealing ring 35 is pressed to the left side of the paper surface while being in close contact with the rotary sealing ring 25 by the urging force of the wave spring 38B, and can move together with the middle holder 32.

Further, since the mechanical seal 10A has a movement allowance in which the inner diameter side cylindrical portion 32e can move in the radial direction in the gap S, the rotating shaft 2 may move in the radial direction or tilt relative to the housing 3. Then, within the range of the radial movement allowance between the sleeve 22 and the case 31, the static sealing ring 35, which is in close contact with the rotary sealing ring 25, is middle in response to the radial movement or tilting of the rotary sealing ring 25. It can be moved together with the holder 32.

As a result, the mechanical seal 10A can allow the rotary shaft 2 to move in the axial direction and the radial direction, and to allow the relative tilt with respect to the housing 3.

Further, since the movement of the O-ring 36 to the right side of the axial paper surface is restricted by the spacer 37, the stationary side element 30 has the bottom portion of the U-shaped portion 31b of the case 31, the inner diameter side cylindrical portion 31b2, and the middle holder. It is prevented that the O-ring 36 is caught between the inner diameter side tubular portion 32e and the inner diameter side tubular portion 32e. As a result, the middle holder 32 can stably move relative to the case 31 in the axial direction.

Further, in the mechanical seal 10A, since the claw portion 22a of the sleeve 22 is locked to the recessed portion 21a of the collar 21 in the rotation side element 20, the sleeve 22 surely follows the rotation shaft 2.

Further, in the mechanical seal 10A, since the claw portion 33c of the inner holder 33 is locked to the concave portion 31e of the case 31 in the stationary side element 30, the inner holder 33 is relative to the case 31 in the circumferential direction. It is prevented from rotating.

As described above, in the mechanical seal 10A, since the wave spring 38A is arranged in the inner diameter side installation space C1 arranged on the atmospheric side A1, the wave spring 38A is prevented from being exposed to the sealed fluid. There is. That is, even if the fluid to be sealed is a high-concentration slurry or a corrosive fluid, the wave spring 38A can be used stably without a risk of clogging or corrosion.

Here, the mechanical seal 10A can be configured by arranging the wave spring 38B in the outer diameter side installation space C2 provided on the outer diameter side of the inner diameter side installation space C1 (FIG. 4). reference). The outer diameter side installation space C2 is an annular shape defined on the outer diameter side of the middle holder 32 and the O-ring 36 by the flange portion 31a of the case 31, the central tubular portion 32c of the middle holder 32, and the outer diameter side wall portion 32b. Space. Further, the wave spring 38B has a larger diameter than the wave spring 38A (see FIG. 4).

In this outer diameter side installation space C2, the outer diameter side wall portion 32b of the middle holder 32 is arranged on the right side of the axial paper surface of the inner holder 33 with the plate thickness, and the flange portion 31a of the case 31 and the flange portion 31a. The case 31 is arranged with a difference in axial position from the wall-shaped portion 31c. In other words, in the inner diameter side installation space C1, the wall-shaped portion 33b of the inner holder 33 is arranged on the left side of the plate thickness portion of the outer diameter side wall-shaped portion 32b of the middle holder 32, and the wall-shaped portion 31c of the case 31 and the wall-shaped portion 31c. The case 31 is arranged with a difference in axial position from the flange portion 31a. The flange portion 31a of the case 31 and the wall-shaped portion 31c of the case 31 may be positioned at the same axial direction.

As a result, the dimension D2 (see FIG. 1) between the outer diameter side wall portion 32b of the facing middle holder 32 and the flange portion 31a of the case 31 is the wall-shaped portion of the facing inner holder 33 of the inner diameter side installation space C1. The dimension D1 (see FIG. 1) between the 33b and the wall-shaped portion 31c of the case 31 is substantially the same (D1 = D2). It should be noted that D1 and D2 do not have to be substantially the same.

In constructing the mechanical seal 10B, the wave spring 38B is supported by the central tubular portion 32c, so that not only is it easy to assemble, but also the wave spring 38B can be positioned accurately. Further, the central tubular portion 32c is a support portion of the urging means in the present embodiment that supports the wave spring 38B and prevents the wave spring 38B from being pulled out in the radial direction.

Further, as shown in FIG. 4, the mechanical seal 10B is used as a so-called outside type. The sealed fluid flows into the balance line B2 indicated by the alternate long and short dash line and presses the middle holder 32 to the left side of the paper surface. The mechanical seal 10B is a balance type in which the balance line B2 is arranged between the outer diameter side end portion and the inner diameter side end portion of the sliding surfaces 25a and 35a of the rotary sealing ring 25 and the static sealing ring 35, respectively, in the radial direction. The balance rate in this example is about 83%.

Further, a gap is formed between the inner diameter side cylindrical portion 32e of the middle holder 32 and the inner diameter side tubular portion 31b2 of the U-shaped portion 31b of the case 31, and the slurry is less likely to stagnate in this gap. The inner diameter side cylindrical portion 32e of the middle holder 32 and the inner diameter side tubular portion 31b2 of the U-shaped portion 31b of the case 31 may be in contact with each other in the radial direction.

Further, since the wave spring 38B is arranged in the outer diameter side installation space C2 located on the atmospheric side A2 of the mechanical seal 10B, the wave spring 38B is exposed to the sealed fluid guided to the sealed fluid side L2. Is prevented. That is, even if the fluid to be sealed is a high-concentration slurry or a corrosive fluid, the wave spring 38B can be used stably without a risk of clogging or corrosion. This makes it possible to provide a highly versatile mechanical seal that can be used without selecting the fluid to be sealed.

Further, if the fluid to be sealed is water, LLC, or the like, the wave spring 38B is not likely to be clogged or corroded, so that the mechanical seal 10B can also be used as an inside type. Similarly, the mechanical seal 10A can also be used as an outside type. That is, the mechanical seals 10A and 10B of the present invention can be used as both the inside type and the outside type, respectively.

Further, the mechanical seals 10A and 10B have a balance ratio of 50% because the pressure receiving surfaces of the inside type or the outside type partially overlap the inner diameter side wall portion 32d of the middle holder 32 and the O-ring 36. It can be configured as a mechanical seal of both balance type that exceeds.

The restricting means for forming the rotating side element and the stationary side element into a cartridge has been described as an embodiment of the flange portion 22d of the annular sleeve 22, but the present invention is not limited to this, and the rotating side element and the stationary side element may be formed in a six-equal arrangement in the circumferential direction. good. In addition, each regulating means may be arranged other than the 6th grade.

Next, the mechanical seal according to the second embodiment will be described with reference to FIG. The same components as those shown in the first embodiment are designated by the same reference numerals, and duplicate description will be omitted. The second embodiment is different from the first embodiment in the urging means and the configuration of the cartridge.

With reference to FIG. 5, in the mechanical seal 110, six coil springs 138 as urging means are arranged in six equal arrangements in the circumferential direction in the inner diameter side installation space C1 or the outer diameter side installation space C2, and the wall of the case 31 is provided. It is welded and fixed to the wall-shaped portion 33b of the shaped portion 31c and the inner holder 33, or to the flange portion 31a of the case 31 and the outer diameter side wall-shaped portion 32b of the middle holder 32. In addition, each coil spring 138 may be arranged other than 6 equal arrangements. Furthermore, each coil spring 138 may be externally or internally fitted and fixed to a convex portion or a concave portion formed in the case 31, the middle holder 32, and the inner holder 33.

Next, the mechanical seal according to the third embodiment will be described with reference to FIG. The same components as those shown in Examples 1 and 2 are designated by the same reference numerals, and duplicate description will be omitted. The configuration of the tubular member of the third embodiment is different from that of the first and second embodiments.

With reference to FIG. 6, in the mechanical seal 210, the central tubular portion 132c of the middle holder 132 as a tubular member is slidably contacted with the outer diameter side tubular portion 31b1 of the U-shaped portion 31b of the case 31 in the circumferential direction. The inner diameter side cylindrical portion 132e of the middle holder 132 is separated from the inner diameter side tubular portion 31b2 of the U-shaped portion 31b of the case 31 so as to be in contact with each other. This makes it possible to prevent the middle holder 32 from being significantly deformed to the outer diameter side due to the pressure of the fluid to be sealed when it is used as an outside type. The central tubular portion 132c of the middle holder 132 may be in a mode in which a portion protruding in the radial direction is in contact with the outer diameter side tubular portion 31b1 of the U-shaped portion 31b of the case 31, and this embodiment may be used. If so, the stagnation of the slurry can be prevented by the voids formed in the non-protruding portion.

Next, the mechanical seal according to the fourth embodiment will be described with reference to FIG. 7. The same components as those shown in the first to third embodiments are designated by the same reference numerals, and duplicate description will be omitted. The fourth embodiment is different from the first to third embodiments in the configuration of the cylindrical member and the support portion of the urging means.

With reference to FIG. 7, in the mechanical seal 310, the central tubular portion 232c of the middle holder 232 as a tubular member has the inner diameter side tubular portion 232b from the inner diameter side end portion to the inner diameter side tubular portion 232e on the left side of the paper surface. It is formed in a tapered shape that inclines toward. As a result, a wide space can be secured between the outer diameter side tubular portion 31b1 of the U-shaped portion 31b of the case 131 and the central tubular portion 232c. Therefore, the outer diameter side tubular portion 31b1 of the U-shaped portion 31b of the case 131 can be secured. The slurry is less likely to stagnate between the central tubular portion 232c and the central tubular portion 232c.

Further, the support portion of the urging means of the outer diameter side installation space C2 is composed of a pair of ribs formed on the flange 131a of the case 131 and the outer diameter side wall-shaped portion 232b of the middle holder 232, respectively. As described above, the support portion of the urging means is not limited as long as it can support the urging means.

Next, the mechanical seal according to the fifth embodiment will be described with reference to FIG. The same components as those shown in Examples 1 to 4 are designated by the same reference numerals, and duplicate description will be omitted. Example 5 has a different configuration of the tubular member from Examples 1 to 4.

With reference to FIG. 8, in the mechanical seal 410, the middle holder 332 as a tubular member is configured vertically symmetrically with the above-described first to fourth embodiments, and the diameter increases from the inner diameter side to the outer diameter side toward the right side of the paper surface. The case 231 and the inner holder 133 as a tubular member are also formed accordingly. As described above, the tubular member may have a shape that can be sealedly divided into the inner diameter side and the outer diameter side on the back surface 35b side of the static sealing ring 35 in combination with the secondary seal, and the same applies to the case. be.

Next, the mechanical seal according to the sixth embodiment will be described with reference to FIG. The same components as those shown in the first to third embodiments are designated by the same reference numerals, and duplicate description will be omitted. The fifth embodiment is different from the first to fourth embodiments in the configuration of the partition means.

With reference to FIG. 9, the mechanical seal 510 employs a bellows 432 having an outer diameter side end portion or an inner diameter side end portion fixed to the case 31 and the inner holder 33 as a partitioning means. As described above, the partitioning means may be capable of partitioning the back surface 35b side of the static sealing ring 35 into the inner diameter side and the outer diameter side in a sealed manner. The secondary seal constituting the partitioning means is not limited to the gasket 34 and the O-ring 36 in Examples 1 to 5 and the bellows 432 in the sixth embodiment, and may be appropriately changed to an elastic member such as a lip packing.

Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these examples, and any changes or additions within the scope of the gist of the present invention are included in the present invention. Is done.

For example, in the above embodiment, the mechanical seal has been described as a so-called fixed type in which the urging means is provided on the stationary side element 30, but the present invention is not limited to this, and the urging means is not limited to the so-called rotary type in which the urging means is provided on the rotating side element. It may be configured as. That is, the back surface 25b side of the rotary sealing ring 25 may be divided into an outer diameter side and an inner diameter side in a sealed manner to form an inner diameter side installation space C1 and an outer diameter side installation space C2.

Further, the mechanical seal has been described as an embodiment that can be used both as an inside type and an outside type, but the present invention is not limited to this, and the mechanical seal may be dedicated to the inside type or the outside type. From this, it does not have to be a double-balanced type, and may be an unbalanced type.

Further, although the mechanical seal has been described as being made into a cartridge, it may not be made into a cartridge, and the stationary side element and the rotating side element may be individually attached to the housing 3 or the rotating shaft 2. .. For example, even if the case 31 is not provided and the middle holder 32 is axially movable with respect to the housing 3, the outer diameter side and the inner diameter side are sealedly partitioned by an O-ring 36. good.

Further, the inner diameter side installation space C1 and the outer diameter side installation space C2 may be formed between the middle holder 32, the inner holder 33, and the O-ring 36, which are partitioning means, and the case 31. A separate member for forming an installation space may be interposed between the middle holder 32 and the case 31.

Further, the inner diameter side installation space C1 may be formed between the inner holder 33 and the flange portion 22d of the sleeve 22, or may be formed between the inner holder 33 and the housing 3, and is limited. It's not a thing. The same applies to the outer diameter side installation space C2.

Further, the middle holder 32 and the inner holder 33, which are tubular members, have been described as separate bodies, but the present invention is not limited to this, and the middle holder 32 and the inner holder 33 may be integrally molded and are not limited thereto. Further, if the static sealing ring 35 and the case 31 are directly detented and the urging means can be arranged between the static sealing ring 35 and the case 31, the inner holder 33 is not provided. It is also good.

Further, although the middle holder 32 has been described as an embodiment formed in a stepped cylindrical shape, it may be a cylindrical shape extending linearly, a bottomed cylindrical shape, or an annular shape. .. This also applies to the inner holder 33.

Further, the urging means has been described as a wave spring 38A, 38B or a coil spring 138, but the present invention is not limited to this, and the urging means can be continuously arranged in the inner diameter side installation space C1 or the outer diameter side installation space C2 in the circumferential direction. It may be a coil spring or a metal bellows having an urging force, and is not limited thereto.

Further, the rotation side element has been described as a mode in which the collar 21 is provided, but the present invention is not limited to this, and the collar is not limited to this, as long as the rotation prevention with respect to the rotation shaft 2 is sufficient only by extrapolating the sleeve 22 to the rotation shaft 2. You do not have to have 21.

Further, the recessed portion 21a, the claw portion 22a, the concave portion 31e, the claw portion 33c, the coil spring 138, and the regulating means may be arranged in a manner other than the six equal arrangements. It may be provided only in a place, or may be unevenly arranged in a plurality of places.

2 Rotating shaft 3 Housing 10A, 10B Mechanical seal 20 Rotating side element 25 Rotating sealing ring 25b Back surface 30 Resting side element 31 Case 32 Middle holder (partitioning means, tubular member)
33 Inner holder (partitioning means, tubular member)
34 Gasket (partition means, secondary seal)
35 Static sealing ring 35b Back surface 36 O-ring (partitioning means, secondary seal)
38A, 38B wave spring (energization means)
39 Seat packing (secondary seal)
110 Mechanical seal 131 Case 132 Middle holder (partitioning means, tubular member)
133 Inner holder (partitioning means, tubular member)
138 Coil spring (urging means)
210 Mechanical Seal 231 Case 232 Middle Holder (Division Means, Cylindrical Member)
310 Mechanical seal 332 Middle holder (partitioning means, tubular member)
410 Mechanical seal 432 Bellows (partitioning means)
510 Mechanical seals A1, A2 Atmospheric side B1, B2 Balance lines C1, C2 Outer diameter side installation space D1, D2 Dimensions H Shaft holes L1, L2 Sealed fluid side S Gap

Claims (6)

A static side element having a static sealing ring and attached to a housing, a rotating side element having a rotating sealing ring and attached to a rotating shaft, and an urging force for urging the static sealing ring and the rotating sealing ring in opposite directions. A mechanical seal with means and
The stationary sealing ring or the rotary sealing ring has a partitioning means for partitioning the back surface side into an inner diameter side and an outer diameter side in a sealed manner, and the urging means is provided on the inner diameter side and the outer diameter side of the partitioning means, respectively. There is an installation space that can be installed ,
A mechanical seal characterized in that the urging means is arranged in one of the installation spaces selected from the installation spaces on the inner diameter side and the outer diameter side of the partition means . The stationary element has a case attached to the housing, the partition means is arranged so as to be movable relative to the case in the axial direction, and the installation space includes the case and the partition means. The mechanical seal according to claim 1, which is formed between the two. The partitioning means has a tubular member for partitioning the static sealing ring and the case, and an annular secondary seal, and the tubular member is hermetically connected to the case by the secondary seal. The mechanical seal according to claim 2, which is provided and is relatively movable in the axial direction. The mechanical seal according to claim 3, wherein the tubular member is formed with a support portion for holding the urging means in the radial direction. The mechanical seal according to any one of claims 2 to 4, wherein the case is formed with a support portion for holding the urging means in the radial direction. The mechanical seal according to any one of claims 1 to 5, wherein the rotating side element and the stationary side element are cartridge-shaped by restricting movement in a direction away from each other in the axial direction.

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