JP6879975B2 - Sealing device mounting structure - Google Patents

Description

The present invention relates to a mounting structure of a sealing device that seals a gap between a shaft and a housing.

Conventionally, a sealing device such as a mechanical seal has been used to seal the gap between the rotating shaft of the rotating machine and the housing. As such a sealing device, for example, a sealing device as in Patent Document 1 is known.

The sealing device of Patent Document 1 prevents the fluid to be sealed in the housing from leaking to the outside, and has a sealing portion which is a primary seal provided with a sliding rotary sealing ring and a static sealing ring, and a seal. A seal cover that covers the portion and is fixed to the housing is provided, and the seal portion seals between the housing and the rotating shaft. Further, the seal cover is provided with an annular protrusion that is inserted into a mounting hole of the housing, and an annular secondary seal member constituting the secondary seal is fitted in the annular groove formed over the outer peripheral surface of the annular protrusion. When the seal cover is attached to the housing from the axial direction using a fastening means such as a bolt, the secondary seal member is pressure-welded between the outer peripheral surface of the annular protrusion and the inner peripheral surface of the mounting hole of the housing. Therefore, the fluid to be sealed in the housing is prevented from leaking to the outside from between the seal cover and the housing.

JP-A-2018-9631 (Page 4, Fig. 1)

In the sealing device of Patent Document 1, the secondary sealing member is pressed between the outer peripheral surface of the annular protrusion and the inner peripheral surface of the mounting hole of the housing to seal between the sealing cover and the housing. Especially when used when the pressure of the fluid to be sealed is high, the secondary sealing member is larger between the outer peripheral surface of the annular protrusion and the inner peripheral surface of the mounting hole of the housing to ensure sufficient sealing performance. It is necessary to press contact with force. In a sealing device as in Patent Document 1, in order to press-contact the secondary sealing member with a large force, the outer peripheral surface of the annular protrusion and the inner peripheral surface of the mounting hole of the housing may be formed close to each other. , The secondary seal member must be formed thick, but in this case, when the annular protrusion is inserted into the mounting hole of the housing, the frictional resistance due to contact with the secondary seal member increases and the secondary seal member increases. The force to compress the seal cover becomes large, and there is a risk that it becomes difficult to attach the seal cover to the housing.

The present invention has been made in view of such problems, and provides a mounting structure for a sealing device that is easy to mount and can reliably seal between the seal cover and the housing. The purpose.

In order to solve the above problems, the mounting structure of the sealing device of the present invention is used.
It is a mounting structure of a sealing device in which a sealing cover having a sealing portion for internally sealing a gap between a shaft and a housing is attached to the housing by fastening means.
The seal cover has an annular protrusion that is inserted into the mounting hole of the housing.
The annular protrusion is provided with a small diameter portion extending to the tip so as to form a step portion.
A tubular body that can move relative to the axial direction is fitted onto the small diameter portion.
An annular secondary seal member is arranged between the tubular body and the step portion.
The mounting hole of the housing is characterized in that a receiving portion that receives an axial force from the tubular body is provided.
According to this feature, when the sealing device is attached to the housing by the fastening means, one end of the tubular body comes into contact with the receiving portion provided in the mounting hole of the housing, and the tubular body has a stepped portion with respect to the small diameter portion. The secondary seal member moves relative to the axial direction in the direction approaching, and the secondary seal member is sandwiched between the tubular body and the step portion to expand the diameter and function as a secondary seal between the seal cover and the housing. Therefore, the sealability between the annular protrusion and the mounting hole of the housing is improved, and the seal cover and the housing can be reliably sealed even when the fluid to be sealed is high pressure. Further, since the diameter of the secondary seal member does not increase until one end of the tubular body comes into contact with the receiving portion, the frictional resistance generated by the secondary seal member when the annular protrusion is inserted into the mounting hole should be suppressed. And the sealing device can be easily attached to the housing.

The receiving portion may be characterized in that it is a back end surface for partitioning the mounting holes.
According to this feature, a receiving portion having high strength and a simple structure can be obtained.

It may be characterized in that a guide means for guiding the relative movement between the tubular body and the small diameter portion in the axial direction is provided.
According to this feature, since the relative movement between the tubular body and the small diameter portion is guided in the axial direction by the guide means, the secondary seal member can be reliably pinched between the tubular body and the step portion. ..

The guide means is also characterized in that it is composed of an elongated hole formed so as to extend in the axial direction with respect to the tubular body and a guide pin that can be inserted into the elongated hole provided in the small diameter portion. Good.
According to this feature, the seal cover and the tubular body can be unitized by the elongated hole and the guide pin, and the rotation of the tubular body with respect to the seal cover is restricted.

It may be characterized that the outer diameter of the tubular body and the outer diameter of the annular protrusion are the same.
According to this feature, the diameter of the secondary seal member can be expanded by evenly applying a force in the axial direction between the tubular body and the step portion.

The tubular body may be characterized in that it is fixed to the small diameter portion by a bolt in a state before the seal cover is attached to the housing.
According to this feature, since the tubular body is fixed to the small diameter portion with bolts, it is possible to prevent the tubular body from moving or vibrating relative to the seal cover.

The secondary seal member may be characterized in that it is a molded product of fluororesin (PTFE).
According to this feature, since the secondary sealing member is made of a fluororesin that is slippery and hard to be deformed, when the secondary sealing member is sandwiched between the tubular body and the step portion, the secondary sealing member is pressed. The seal member is less likely to be twisted and can be deformed evenly in the circumferential direction.

It is sectional drawing which shows the mounting structure of the sealing device in the Example of this invention. (A) is an enlarged cross-sectional view of a main part showing a mounting structure of a seal cover and a tubular body, and (b) is an enlarged top view of the same. It is an enlarged sectional view of the main part which shows the state which the secondary seal member is in contact with a step part and a tubular body respectively. (A) is a cross-sectional view showing a state before mounting such as during transportation of the sealing device, and (b) is a cross-sectional view showing a state at the time of mounting the sealing device. (A) to (c) are enlarged cross-sectional views of a main part showing a flow until the sealing device is attached to the housing.

A mode for carrying out the mounting structure of the sealing device according to the present invention will be described below based on examples.

The mounting structure of the sealing device according to the embodiment will be described with reference to FIGS. 1 to 5. In this embodiment, the right side of the paper surface will be described as the atmosphere side, and the left side of the paper surface will be described as the inside of the machine.

As shown in FIG. 1, the sealing device 1 of the present embodiment is a mechanical seal provided for sealing the shaft between the rotating shaft 2 (shaft) of a rotating machine such as a pump or a compressor and the housing 3. Is. In this embodiment, a mode in which the sealing device 1 is a mechanical seal is illustrated, but if the shaft seals between the shaft on the machine side and the housing, for example, a lip seal, a segment seal, a labyrinth seal, etc. It may be a sealing device of.

The sealing device 1 includes a sealing cover 5 attached to the housing 3, an annular rotary sealing rings 20 and 21 fixed to the rotating shaft 2 via a sleeve 4, and an annular fixed sealing fixed to the sealing cover 5. The sliding surfaces 20a of the rotary sealing rings 20 and 21 are mainly composed of the rings 30 and 31, and the rotary sealing rings 20 and 21 are urged in the axial direction by the metal bellows members 60 and 61, respectively. , 21a and the sliding surfaces 30a, 31a of the fixed sealing rings 30, 31 are slid closely with each other so that the sealed fluid in the machine can be shaft-sealed. That is, the rotary sealing rings 20 and 21 and the fixed sealing rings 30 and 31 constitute the sealing portion in this embodiment. The sealing device 1 of the present embodiment is configured as a so-called double mechanical seal in which the rotary sealing ring 20 and the fixed sealing ring 30 on the atmospheric side and the rotary sealing ring 21 and the fixed sealing ring 31 inside the machine face in opposite directions. ing. The sealing device 1 is not limited to the double type mechanical seal, and may be a tandem type or a single type mechanical seal.

The rotary sealing rings 20, 21 and the fixed sealing rings 30, 31 are typically formed of SiC (hard materials) or a combination of SiC (hard material) and carbon (soft material), but the present invention is not limited to this. The sliding material can be applied as long as it is used as a sliding material for mechanical sealing. The SiC includes a sintered body using boron, aluminum, carbon and the like as a sintering aid, and materials composed of two or more types of phases having different components and compositions, for example, SiC and SiC in which graphite particles are dispersed. There are reaction-sintered SiC, SiC-TiC, SiC-TiN and the like made of Si, and as carbon, resin-molded carbon, sintered carbon and the like can be used, including carbon in which carbon and graphite are mixed. In addition to the above sliding materials, metal materials, resin materials, surface modification materials (coating materials), composite materials and the like can also be applied.

Collars 22 and 23 are fixed to the substantially central portion of the sleeve 4 toward the atmosphere side and the inside of the machine (facing in the opposite direction), and one end of the bellows members 60 and 61 is fixed to the collars 22 and 23. Has been done. Further, retainers 24 and 25 for holding the rotary sealing rings 20 and 21 are fixed to the other ends of the bellows members 60 and 61.

Further, a sleeve collar 9 is attached to the end of the sleeve 4 on the atmosphere side by a set screw 10a at a plurality of locations in the circumferential direction, and the sleeve collar 9 and the sleeve collar 9 are attached by a plurality of set screws 10b penetrating the sleeve 4. And the sleeve 4 is fixed to the rotating shaft 2.

A concave groove 9a recessed on the inner diameter side is formed on the outer peripheral surface of the sleeve collar 9, and a set plate 12 fixed to the end portion of the seal cover 5 on the atmosphere side is fitted in the concave groove 9a. There is. After fixing the sealing device 1 to the rotating shaft 2, the set plate 12 is removed. That is, the sealing device 1 in this embodiment is a cartridge type sealing device in which the sleeve 4 and the sealing cover 5 are positioned in the axial direction and integrally formed.

The seal cover 5 is made of stainless steel and is formed in a substantially cylindrical shape, and a through hole 5b through which the rotating shaft 2 and the sleeve 4 can be inserted is formed inside the cylindrical portion 5a. Further, on the inside of the machine of the seal cover 5, an annular protrusion 5c that can be inserted into the mounting hole 3a formed in the housing 3 is provided so as to project inside the machine with a diameter smaller than that of the cylindrical part 5a.

A retainer 32 for holding the fixed sealing ring 30 is fixed to the atmosphere side on the inner diameter side of the seal cover 5, and inside the machine on the inner diameter side of the seal cover 5 (inside the machine of the annular protrusion 5c). The retainer 33 that holds the fixed sealing ring 31 is fixed. A baffle sleeve 8 with a bush 8a arranged between the retainer 33 and the rotating shaft 2 is attached to the retainer 33, and the sliding surface 21a of the rotary sealing ring 21 and the fixed sealing ring 31 pass through the flow path P1. The flushing fluid can be guided to the sliding surface 31a of the above. The retainer 33 is fixed to the seal cover 5 by a screw 70 in a unitized state with the fixed sealing ring 31 and the baffle sleeve 8.

The flushing flow path P1 includes a hole 3d provided in the housing 3, a hole 6a provided in the tubular body 6 described later, a hole 5g provided in the annular protrusion 5c, and a hole 33a provided in the retainer 33. And are configured to communicate in the radial direction.

An annular groove portion 5e into which the O-ring 7 is inserted is provided on the side end surface 5d inside the machine of the cylindrical portion 5a. As will be described later, the O-ring 7 prevents the quenching fluid that flows out from the notch hole portion of the outflow path P3 between the housing 3 and the seal cover 5 to flow out to the outside (atmosphere side). The O-ring 7 may be made of an elastic body, and the material may be rubber, resin, graphite, or the like. Further, the cylindrical portion 5a is provided with a plurality of insertion holes 5f in the circumferential direction into which fixing screws 11 (fastening means) for fastening the seal cover 5 to the housing 3 can be inserted (only one is shown in FIG. 1).

Further, the seal cover 5 has an inflow path P2 for flowing the quenching fluid from the outer diameter side to the inner diameter side of the cylindrical portion 5a, and an outflow for flowing out the quenching fluid from the inner diameter side to the outer diameter side of the cylindrical portion 5a. A plurality of roads P3 are formed in the circumferential direction (only one road P3 is shown in FIG. 1). By circulating the quenching fluid between the inside and the outside of the cylindrical portion 5a in this way, a small amount of the sealed fluid leaking from between the sliding surfaces 21a and 31a between the rotary sealing ring 21 and the fixed sealing ring 31 is recovered. You can do it.

The outflow path P3 in this embodiment is formed by partially cutting out a corner portion formed by the cylindrical portion 5a and the annular protrusion 5c.

As shown in FIG. 1, the sealing device 1 in the present embodiment has a tubular body 6 that is externally fitted to the tip of the annular protrusion 5c, and a step portion 52 (side) of the tubular body 6 and the annular protrusion 5c. It is hermetically attached to the housing 3 via an annular secondary seal member 13 that is axially pressed between the end face 52B). Specifically, the secondary seal is composed of a secondary seal member 13, a housing 3, a step portion 52, and a tubular body 6, and the fluid to be sealed in the housing 3 is formed by a mounting hole 3a and an annular protrusion 5c. In addition to preventing leakage from the space, the quenching fluid flowing out from the notch hole portion of the outflow path P3 between the housing 3 and the annular protrusion 5c is prevented from being mixed into the housing 3.

Next, a mounting structure (secondary seal) for mounting the sealing device 1 to the housing 3 in a sealed manner will be described with reference to FIGS. 2 to 4. 2 to 4 show a state before the sealing device 1 is attached to the housing 3.

As shown in FIG. 2A, a small diameter portion 51 extending from the tip of the annular protrusion 5c toward the atmosphere by a predetermined distance is formed at the tip of the annular protrusion 5c, and the small diameter portion 51 and the small diameter portion 51 are formed. A step portion 52 is formed between the annular protrusion 5c and the annular protrusion 5c. Specifically, the stepped portion 52 is orthogonal to the outer peripheral surface 52A of the small diameter portion 51, the side end surface 52B orthogonal to the outer peripheral surface 52A and extending in the outer diameter direction, and the outer diameter end of the side end surface 52B (the outer peripheral surface 52A). It is composed of an outer peripheral surface 52C of an annular protrusion 5c extending in the axial direction (in parallel). Further, a guide pin 53 (guide means) can be attached to and detached from the outer peripheral surface 52A of the small diameter portion 51 so as to project in the outer diameter direction.

As shown in FIGS. 2A and 2B, the tubular body 6 is made of stainless steel and has an annular shape that can be fitted onto the outer peripheral surface 52A of the small diameter portion 51. The outer diameter of the tubular body 6 is substantially the same as the outer diameter of the outer peripheral surface 52C of the annular protrusion 5c.

Further, the tubular body 6 is formed with an elongated hole 6b (guide means) which is elongated in the axial direction and penetrates in the radial direction, and a guide pin is formed in the elongated hole 6b in a state of being externally fitted to the small diameter portion 51. Since 53 is inserted and the elongated hole 6b is elongated in the axial direction, the tubular body 6 and the annular protrusion 5c can be relatively moved in the axial direction. That is, the tubular body 6 and the annular protrusion 5c have a gap dimension L10 formed between the guide pin 53 and the inner end of the elongated hole 6b, and the guide pin 53 and the elongated hole 6b on the atmospheric side. The sliding movement is in the axial direction by the amount of the gap dimension L11 formed between the end portion and the end portion. Further, since the guide pin 53 is in sliding contact with the side surface of the elongated hole 6b in the circumferential direction, the movement of the tubular body 6 in the circumferential direction with respect to the small diameter portion 51 is restricted.

Further, by inserting the guide pin 53 into the elongated hole 6b, the tubular body 6 is prevented from coming off from the small diameter portion 51. Specifically, after the tubular body 6 is fitted onto the small diameter portion 51, the tubular body 6 and the seal cover 5 cannot be separated by attaching the guide pin 53 to the small diameter portion 51 from the outer diameter side through the elongated hole 6b. Is unitized into.

The secondary seal member 13 is an O-ring formed of a fluororesin such as PTFE, and is arranged between the tubular body 6 in the small diameter portion 51 and the side end surface 52B of the step portion 52. The secondary sealing member 13 has characteristics such as excellent corrosion resistance and heat resistance as compared with a secondary sealing member such as rubber, and is useful when the sealed fluid is highly corrosive or in a high temperature environment. is there. In addition to the above characteristics, the secondary seal member 13 has characteristics such as lower elasticity, less deformation, and slipperiness than the secondary seal member containing rubber as a main component. In this embodiment, the form in which the secondary seal member 13 is an O-ring is illustrated, but the cross section may be a rectangular cross section other than a circular cross section, an X cross section, a polygonal cross section, or the like.

As shown in FIG. 3, the tubular body 6 and the secondary seal member 13 are attached to the small diameter portion 51, and the secondary seal member 13 is the side end surface 52B of the step portion 52 and the end of the tubular body 6 on the atmosphere side. In the state of being in contact with the portion 6d, the end portion 6e on the inside of the machine of the tubular body 6 is located inside the machine with the dimension L12 minutes and the tip of the small diameter portion 51.

As shown in FIG. 4A, the tubular body 6 is fixed to the small diameter portion 51 by the bolt 40 before the sealing device 1 is attached to the housing 3 during transportation or carrying. Specifically, the tubular body 6 is formed with through holes 6c in a phase different from that of the elongated holes 6b in the circumferential direction, and the small diameter portion 51 has a phase different from the portion to which the guide pin 53 is attached. Moreover, a screw hole 51a is formed at a position displaced in the axial direction from the hole 5g constituting the flow path P1.

The through hole 6c and the screw hole 51a are communicated with each other in a state where the guide pin 53 of the small diameter portion 51 is inserted into the elongated hole 6b of the tubular body 6, and the through hole 6c and the screw hole 51a are communicated with each other. By inserting and screwing the bolt 40 into the tubular body 6, the tubular body 6 and the small diameter portion 51 are fixed. By fixing the tubular body 6 to the small diameter portion 51 with the bolt 40 in this way, the relative movement and vibration of the tubular body 6 with respect to the seal cover 5 can be prevented, so that the sealing device 1 can be transported during transportation. Or, it is possible to prevent the tubular body 6 and the seal cover 5 from being damaged during carrying.

As shown in FIG. 4B, when the sealing device 1 is attached to the housing 3, the bolt 40 is removed. As a result, when the sealing device 1 is attached, the secondary sealing member 13 is stepped with the tubular body 6 so that the tubular body 6 and the annular protrusion 5c can move relative to each other in the axial direction. Prepare to be sandwiched between the side end surface 52B of the portion 52.

Next, the flow until the sealing device 1 is attached to the housing 3 will be described with reference to FIG. First, although not shown, the sleeve 4, the rotary sealing rings 20, 21, the fixed sealing rings 30, 31 and the like are incorporated inside the seal cover 5, and the seal cover 5 and the sleeve 4 are positioned in the axial direction by the set plate 12. , Assemble the cartridge type sealing device 1.

Next, as shown in FIG. 5A, the tubular body 6 and the secondary seal member 13 are attached to the small diameter portion 51, and the annular protrusion 5c is inserted into the mounting hole 3a of the housing 3. Before inserting the annular protrusion 5c into the mounting hole 3a of the housing 3, the tubular body 6 and the annular protrusion 5c are set to be relatively movable in the axial direction (see FIG. 4B).

When the annular protrusion 5c is inserted into the mounting hole 3a of the housing 3, the secondary seal member 13 slides along the inner peripheral surface of the mounting hole 3a, but the secondary seal member 13 is slippery. Since it has, it is easy to insert the annular protrusion 5c into the mounting hole 3a.

Next, after the annular protrusion 5c is manually inserted into the mounting hole 3a to some extent, the fixing screw 11 is inserted into the insertion hole 5f of the seal cover 5 as shown in FIG. 5B, and the fixing screw 11 is inserted. Tighten the screw hole 3b of the housing 3.

When the fixing screw 11 is tightened to some extent with respect to the screw hole 3b of the housing 3, the end portion 6e of the tubular body 6 comes into contact with the back end surface 3e that partitions the radial surface of the mounting hole 3a, and the machine of the tubular body 6 The movement inward is restricted, and the seal cover 5 moves relative to the tubular body 6 in a direction close to the tubular body 6, so that the end portion 6d of the tubular body 6 is in contact with the secondary seal member 13. .. That is, the back end surface 3e of the mounting hole 3a functions as a receiving portion that receives an axial force of the tubular body 6 and regulates the movement in the axial direction. In FIG. 5B, the end portion 6d of the tubular body 6 and the side end surface 52B of the step portion 52 are in contact with the secondary seal member 13, but the secondary seal member 13 is not compressed. Is illustrated.

As shown in FIG. 5C, when the fixing screw 11 is tightened from the state of FIG. 5B until the side end surface 5d of the cylindrical portion 5a comes into contact with the end portion 3c of the housing 3, the seal cover 5 is released. The secondary seal member 13 further moves relative to the tubular body 6 in a direction closer to the tubular body 6, and the secondary seal member 13 is axially pinched by the end portion 6d of the tubular body 6 and the side end surface 52B of the step portion 52 to expand the diameter. Will be. As a result, the secondary seal member 13 is deformed so that the inner diameter side of the secondary seal member 13 is pressed against the outer peripheral surface 52A and the outer diameter side of the secondary seal member 13 is pressed against the inner peripheral surface of the mounting hole 3a. Therefore, the pressure contact force between the secondary sealing member 13, the outer peripheral surface 52A of the small diameter portion 51, and the inner peripheral surface of the mounting hole 3a is increased, and the sealing performance is improved.

After that, the sleeve collar 9 and the sleeve 4 are fixed to the rotating shaft 2 by the set screw 10b, and the set plate 12 is removed to complete the attachment of the sealing device 1 to the housing 3.

According to this, in the mounting structure of the sealing device 1 of the present embodiment, when the sealing device 1 is mounted on the housing 3 by the fixing screw 11, the end portion 6e inside the machine of the tubular body 6 is the mounting hole 3a of the housing 3. The tubular body 6 moves relative to the small diameter portion 51 in the direction closer to the step portion 52, and the secondary seal member 13 moves to the tubular body 6 (on the atmospheric side) in contact with the back end surface 3e provided as a receiving portion. Since the diameter is expanded by being pinched in the axial direction between the end portion 6d) and the step portion 52 (side end surface 52B), the sealing property between the annular protrusion 5c and the mounting hole 3a of the housing 3 is improved. Even when the fluid to be sealed is at high pressure, the seal cover 5 and the housing 3 can be reliably sealed. Further, since the diameter of the secondary seal member 13 does not increase until the inner end portion 6e of the tubular body 6 comes into contact with the inner end surface 3e of the mounting hole 3a, when the annular protrusion 5c is inserted into the mounting hole 3a. The frictional resistance generated by the secondary seal member 13 can be suppressed, the seal device 1 can be easily attached to the housing 3, and the secondary seal member 13 is less likely to be damaged during insertion.

Further, since the receiving portion of the housing 3 with which the inner end portion 6e of the tubular body 6 contacts is the back end surface 3e for partitioning the mounting hole 3a, the receiving portion has a high strength and a simple structure. Can be done.

Further, between the tubular body 6 and the small diameter portion 51, an elongated hole 6b formed so as to extend in the axial direction with respect to the tubular body 6 and a guide provided in the small diameter portion 51 and inserted into the elongated hole 6b. Since it is composed of a pin 53 and is provided with a guide means for guiding the relative movement between the tubular body 6 and the small diameter portion 51 in the axial direction, the secondary seal member 13 is attached to the tubular body 6 and the step portion 52. It can be reliably clamped in the axial direction with the side end surface 52B. Specifically, since the elongated hole 6b and the guide pin 53 restrict the movement of the tubular body 6 in the circumferential direction with respect to the small diameter portion 51, the tubular body 6 and the side end surface 52B of the step portion 52 are separated from each other. When the secondary seal member 13 is pressed, the secondary seal member 13 is prevented from being twisted. In other words, since the secondary seal member 13 can be pressed in the axial direction, the diameter of the secondary seal member 13 can be uniformly expanded in the circumferential direction. A plurality of elongated holes 6b and guide pins 53 may be provided in the circumferential direction of the tubular body 6 and the small diameter portion 51.

Further, since the outer diameter of the tubular body 6 is substantially the same as the outer diameter of the annular protrusion 5c, the secondary seal member 13 is shafted between the tubular body 6 and the side end surface 52B of the step portion 52. The force can be applied evenly in the direction to pinch. Specifically, when a step in the radial direction occurs between the tubular body 6 and the annular protrusion 5c, the secondary seal member 13 compressed in the step portion may escape. In the sealing device 1 of the embodiment, since the outer diameter of the tubular body 6 and the outer diameter of the annular protrusion 5c are substantially the same as the inner peripheral surface of the mounting hole 3a, the diameter of the secondary sealing member 13 is expanded. When this is done, the secondary seal member 13 can be efficiently pressed against the inner peripheral surface of the mounting hole 3a.

Further, when the secondary seal member 13 is made of a fluororesin that is slippery and hard to be deformed, the secondary seal member 13 is axially sandwiched between the tubular body 6 and the step portion 52. In addition, the secondary seal member 13 is less likely to be twisted and can be deformed evenly in the circumferential direction. Further, since the tubular body 6 is inserted through the small diameter portion 51 after the secondary seal member 13 is inserted through the small diameter portion 51, the inner diameter of the secondary seal member is increased and fitted into the groove portion as in the conventional case. There is no need for a step of inserting, and even a secondary seal member 13 with low elasticity, so-called squeeze packing, can be easily assembled to the seal cover 5.

Although examples 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 secondary sealing member 13 has been described as being formed of a fluororesin such as PTFE, but the material of the secondary sealing member is the environment in which the sealing device 1 is used and the fluid to be sealed. It may be changed as appropriate depending on the nature.

Further, in the above embodiment, the configuration in which the back end surface 3e of the mounting hole 3a of the housing 3 functions as the receiving portion of the tubular body 6 has been described, but the present invention is not limited to this, and for example, the receiving portion is formed from the inner circumference of the mounting hole 3a. It may be a protruding portion (for example, a pin) projecting in the inner diameter direction, and may not be in contact with the end portion 6e inside the machine of the tubular body 6 in the circumferential direction.

Further, the receiving portion may be provided only on the outer diameter side of the small diameter portion 51, for example, as long as it can come into contact with the tubular body 6 before the tip of the small diameter portion 51. Further, in the case of the above configuration, when the tubular body 6 and the side end surface 52B of the step portion 52 are in contact with the secondary seal member 13, the inner end portion 6e of the tubular body 6 does not necessarily have a small diameter. It does not have to be located inside the machine from the tip of the portion 51.

Further, in the above embodiment, the step portion 52 has a shaft between the small diameter portion 51 and the annular protrusion 5c due to the formation of the small diameter portion 51 extending from the tip of the annular protrusion 5c toward the atmosphere side by a predetermined distance. Although it has been described as being formed at right angles to the direction, the step portion is not limited to this, and for example, the small diameter portion and the cylindrical portion are formed by forming the small diameter portion directly from the end face inside the machine of the cylindrical portion of the seal cover. It may be formed at right angles to the axial direction. Further, the side end surface 52B of the step portion 52 may be formed so as to be inclined with respect to the axial direction.

Further, the guide means may be freely configured as long as it can guide the relative movement between the tubular body 6 and the small diameter portion 51 in the axial direction. For example, a small diameter is provided between the tubular body and the small diameter portion. It may be composed of an elongated hole formed so as to extend in the axial direction with respect to the portion, and a guide pin provided in the tubular body and inserted into the elongated hole. Further, the hole is not limited to the elongated hole, and may be a notched groove having an open end in the axial direction. Further, the sealing device does not necessarily have to be provided with a guide means.

1 Sealing device 2 Rotating shaft (axis)
3 Housing 3a Mounting hole 3b Screw hole 3c End 3e Back end surface (receiving part)
4 Sleeve 5 Seal cover 5a Cylindrical part 5b Through hole 5c Circular protrusion 5d End face 5f Insertion hole 6 Cylindrical body 6b Long hole (guide means)
6c Through hole 6d End 6e End 11 Fixing screw (fastening means)
13 Secondary sealing member 20, 21 Rotating sealing ring 20a, 21a Sliding surface 30, 31 Fixed sealing ring 30a, 31a Sliding surface 40 Bolt 51 Small diameter portion 51a Screw hole 52 Step portion 53 Guide pin (guide means)
60,61 bellows member

Claims (7)

It is a mounting structure of a sealing device in which a sealing cover having a sealing portion for internally sealing a gap between a shaft and a housing is attached to the housing by fastening means.
The seal cover has an annular protrusion that is inserted into the mounting hole of the housing.
The annular protrusion is provided with a small diameter portion extending to the tip so as to form a step portion.
A tubular body that can move relative to the axial direction is fitted onto the small diameter portion.
An annular secondary seal member is arranged between the tubular body and the step portion.
A mounting structure for a sealing device, wherein the mounting hole of the housing is provided with a receiving portion that receives an axial force from the tubular body. The mounting structure for a sealing device according to claim 1, wherein the receiving portion is a back end surface for partitioning the mounting holes. The mounting structure for a sealing device according to claim 1 or 2, wherein a guide means for guiding the relative movement between the tubular body and the small diameter portion in the axial direction is provided. The guide means is characterized by being composed of an elongated hole formed so as to extend in the axial direction with respect to the tubular body, and a guide pin that can be inserted into the elongated hole provided in the small diameter portion. The mounting structure of the sealing device according to claim 3. The mounting structure for a sealing device according to any one of claims 1 to 4, wherein the outer diameter of the tubular body and the outer diameter of the annular protrusion are the same. The sealing device according to any one of claims 1 to 5, wherein the tubular body is fixed to the small diameter portion by a bolt in a state before the sealing cover is attached to the housing. Mounting structure. The mounting structure for a sealing device according to any one of claims 1 to 6, wherein the secondary sealing member is a molded product of fluororesin (PTFE).

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