JP6581179B2 - Mechanical seal device, double seal device and double mechanical seal device - Google Patents

Description

  The present invention relates to a mechanical seal device, a double seal device, and a double mechanical seal device used for, for example, a pump and a generator.

  For example, as a mechanical seal device used for a pump, a device shown in Patent Document 1 below is known. In this mechanical seal device, a stationary sealing ring is provided on the inner peripheral side of the pump housing via a cup gasket. The rotational sliding surface of the rotary sealing ring slides on the stationary sliding surface of the stationary sealing ring.

  In a conventional mechanical seal device, a cup gasket is joined to the outer peripheral surface of a stationary seal ring by a baking process (vulcanization process). By the baking process, a rubber cup gasket and a stationary sealing ring made of metal, ceramic, or the like are integrated, and handling is improved.

  However, conventionally, the stationary seal ring may crack due to the influence of contact with the mold during vulcanization of the cup gasket, vulcanization pressure, and the like. In particular, cracks in ceramic static seal rings are difficult to detect and require a lot of time for inspection. This tendency has become remarkable with the increase in the size of the mechanical seal device.

  Therefore, it is conceivable that the stationary seal ring and the cup gasket are not joined by a baking process or the like. However, in the conventional structure, if the stationary sealing ring and the cup gasket are not joined by baking, etc., the cup gasket may protrude from the outer peripheral surface of the stationary sealing ring due to the pressure of the sealed fluid. It was.

  In the conventional mechanical seal device, the back surface of the stationary seal ring (the surface opposite to the stationary sliding surface in the axial direction) is in direct contact with the stepped surface of the housing. As a result, the slurry in the fluid to be sealed enters, and foreign matter tends to accumulate.

  If foreign matter enters between the back of the stationary seal ring and the stepped surface of the housing, the foreign matter will be caught between the back of the stationary seal ring and the stepped surface of the housing when the pressure of the sealed fluid drops. As a result, the stationary sliding surface of the stationary seal ring is distorted, and a gap is formed between the stationary sliding ring and the rotating sliding surface, and fluid may leak from there. Further, if a foreign object is caught between the back surface of the stationary seal ring and the stepped surface of the housing, the durability of the stationary seal ring is deteriorated.

JP 2010-19083 A

  The present invention has been made in view of such a situation, and an object thereof is to reduce the possibility that the cup gasket protrudes outward from the outer peripheral surface of the stationary sealing ring, and further, between the back surface of the stationary sealing ring and the stepped surface of the housing. It is an object to provide a mechanical seal device, a double seal device, and a double mechanical seal device in which foreign matter is not easily caught between them.

In order to achieve the above object, a mechanical seal device according to the present invention comprises:
An elastic seal member attached to the outer periphery of a rotating shaft rotatable inside the housing so as to rotate together with the rotating shaft;
A rotary seal ring attached to the shaft end of the elastic seal member and rotating together with the elastic seal member;
A stationary sealing ring having a stationary sliding surface sliding with the rotating sealing ring;
A cup gasket held between the stationary seal ring and the housing;
A washer that prevents the cup gasket from moving axially relative to the housing;
The cup gasket is
A gasket body capable of being compressed and held between an outer peripheral surface of the stationary seal ring and a partial inner peripheral surface of the housing;
An inward convex portion that is molded integrally with the gasket body and projects radially inward,
The inward convex portion can be compressed and held in the axial direction between a back surface located on the opposite side to the stationary sliding surface of the stationary sealing ring in the axial direction and the housing. It is characterized by being.

  In the mechanical seal device according to the present invention, an inward convex portion is formed on the gasket body of the cup gasket. The inward convex portion is held between the back surface of the stationary sealing ring and the stepped surface of the housing, and covers at least a part of the back surface of the stationary sealing ring. Therefore, the force based on the pressure of the fluid to be sealed acting on the back surface of the stationary seal ring is reduced as compared with the conventional case, and the force for increasing the distance between the back surface of the stationary seal ring and the stepped surface of the housing is reduced. Further, the washer prevents the cup gasket from moving in the axial direction with respect to the housing.

  As a combined action of these, in the mechanical seal device of the present invention, even if the size is increased, the cup gasket is less likely to come out from the outer peripheral surface of the stationary seal ring due to the pressure of the sealed fluid. Will improve.

  Further, in the mechanical seal device of the present invention, as described above, the force based on the pressure of the sealed fluid acting on the back surface of the stationary seal ring is smaller than the conventional one, and the back surface of the stationary seal ring and the stepped surface of the housing The force to increase the distance between is reduced. For this reason, there is less possibility that foreign matter in the slurry is caught between the back surface of the stationary seal ring and the stepped surface of the housing. As a result, the stationary sliding surface of the stationary sealing ring is not distorted, and the sealing performance is improved. Furthermore, the stationary seal ring is less damaged by foreign matter, and the durability of the stationary seal ring is improved.

  In the mechanical seal device of the present invention, even if the size of the mechanical seal device is increased, the cup gasket is less likely to come out from the outer peripheral surface of the stationary seal ring due to the pressure of the sealed fluid. The cup gasket is not joined but may simply be in pressure contact. Therefore, it is not necessary to bake the cup gasket on the stationary seal ring, and cracks of the stationary seal ring can be effectively prevented.

  Preferably, at least one of the gasket body and the washer is formed with a fitting portion that suppresses relative rotation. By suppressing the relative rotation of the gasket body, the stationary seal ring can be prevented from rotating together with the rotary seal ring.

  A disk-shaped case may be interposed between the gasket body and the washer. The disc-shaped case and the cup gasket may be integrated by a baking process. The disc-shaped case is made of metal and is unlikely to crack unlike ceramics. In addition, you may form the fitting part which becomes those rotation prevention between a disk-shaped case and a washer.

  The inner end of the washer in the radial direction may be configured to restrict axial movement of the stationary seal ring. For example, the radially inner end of the washer may be locked to the stationary seal ring to limit axial movement of the stationary seal ring toward the rotary seal ring. With this configuration, the distance between the back surface of the stationary seal ring and the stepped surface of the housing can be kept substantially constant, and the compressive force acting on the inward convex portion of the cup gasket becomes substantially constant. , Sealing performance is improved.

  An outward convex portion may be formed on the outer peripheral surface of the stationary seal ring. By comprising in this way, a cup gasket becomes difficult to remove | deviate from the outer peripheral surface of a stationary sealing ring.

FIG. 1 is a schematic cross-sectional view of a double mechanical seal device according to an embodiment of the present invention. FIG. 2 is a half sectional perspective view showing a combination of the first stationary sealing ring and the first cup gasket shown in FIG. 3 is an enlarged cross-sectional view of the vicinity of the sliding surface between the first stationary seal ring and the first rotary seal ring shown in FIG. FIG. 4 is a schematic cross-sectional view of a double mechanical seal device according to another embodiment of the present invention. FIG. 5 is a half sectional exploded perspective view showing a combination of the first stationary seal ring, the first cup gasket and the case shown in FIG. FIG. 6 is a schematic cross-sectional view of a double mechanical seal device according to still another embodiment of the present invention. FIG. 7 is a schematic cross-sectional view of a double mechanical seal device according to still another embodiment of the present invention. FIG. 8 is a half sectional perspective view showing a combination of the first stationary seal ring and the first cup gasket shown in FIG.

  Hereinafter, the present invention will be described based on embodiments shown in the drawings.

First Embodiment As shown in FIG. 1, a double mechanical seal device 2 according to an embodiment of the present invention comprises a first mechanical seal device 2a and a second mechanical seal device 2b. The double mechanical seal device 2 seals a gap between the outer peripheral surface of the rotating shaft 6 rotatable inside the first housing 4a and the second housing 4b and the inner peripheral surfaces of the housings 4a and 4b.

  The first housing 4a is, for example, a pump housing, and water, for example, as a sealed fluid is sealed in the pump chamber 8a therein. The second housing 4b is, for example, a motor or generator housing, and air is sealed, for example, in the drive chamber 8b therein. An oil chamber 10 is provided around the rotary shaft 6 between the first housing 4a and the second housing 4b, and the oil chamber 10 is filled with oil.

  The first mechanical seal device 2a and the second mechanical seal device 2b basically have the same configuration. The following description has the same configuration unless otherwise specified.

  The first mechanical seal device 2a includes a first bellows 12a as a first elastic seal member, a first rotating seal ring 30a attached to the first bellows 12a, and a first sliding with respect to the first rotating seal ring 30a. It has a stationary seal ring 40a and a first cup gasket 50a attached between the first stationary seal ring 40a and the first housing 4a.

  Similarly, the second mechanical seal device 2b is slid with respect to the second bellows 12b as the second elastic seal member, the second rotary seal ring 30b attached to the second bellows 12b, and the first rotary seal ring 30b. And a second cup gasket 50b attached between the second stationary seal ring 40b and the second housing 4b.

  The first bellows 12a and the second bellows 12b are attached to the outer peripheral surface of the rotary shaft 6 so as to face each other in the opposite directions along the axis C of the rotary shaft 6 at a predetermined interval. The first bellows 12a and the second bellows 12b have the same configuration except that their directions are different. Hereinafter, the first mechanical seal device 2a including the first bellows 12a will be described, and a part of the description of the second mechanical seal device 2b including the second bellows 12b will be omitted.

  The first bellows 12a has a cylindrical portion 14a attached in close contact with the outer peripheral surface of the rotary shaft 6, and a bellows portion 16a formed integrally with one end of the cylindrical portion 14a close to the first housing 4a. In order to bring the cylindrical portion 14 a into close contact with the outer peripheral surface of the rotating shaft 6, a tightening ring 18 a is disposed on the outer peripheral surface of the cylindrical portion 14 a, and the cylindrical portion 14 a is tightened to the outer peripheral surface of the rotating shaft 6.

  The bellows portion 16a can be elastically deformed along the direction of the axis C of the rotary shaft 6, and the back surface of the first rotary seal ring 30a is unevenly fitted to the outer peripheral portion of the bellows portion 16a. As shown in FIG. 3, the ring-shaped outer peripheral portion of the bellows portion 16a and the outer peripheral portion of the first rotary seal ring 30a are integrated by a caulking portion 22a of the first mounting bracket 20a. In the present embodiment, the side facing the sliding surfaces 32a, 42a, 32b, and 42b is referred to as a front surface (front), and the surface facing the opposite side is referred to as a back surface (rear).

  On the inner peripheral surface of the caulking portion 22a, an inward convex portion 24a for preventing rotation is formed at one or more positions along the circumferential direction, and the inward convex portion 24a is formed in the first rotation. Engage with the fitting notch 34a formed on the outer peripheral surface of the sealing ring 30a, and the rotation is prevented.

  A bellows back portion 26a is formed integrally with the caulking portion 22a of the first mounting bracket 20a. The bellows back surface portion 26a contacts the back surface of the bellows portion 16a (the side surface opposite to the joint surface with the first rotary seal ring 30a) and holds the bellows portion 16a. A ring fitting portion 28a is formed integrally with the bellows back portion 26a. The ring fitting portion 28a is fitted to the tightening ring 18a. For this reason, the first mounting bracket 20a, the first bellows 12a, and the first rotary seal ring 30a can be rotated together with the rotary shaft 6 around the axis C thereof.

  The first bellows 12a is made of a material that can be elastically deformed, such as rubber, synthetic resin, or a spring material. The fastening ring 18a and the first mounting bracket 20a are made of metal, for example. The first rotating seal ring 30a is made of, for example, a metal such as carbon, SiC, ceramic, or cemented carbide.

  In the present embodiment, the first rotational sliding surface 32a of the first rotational sealing ring 30a and the second rotational sliding surface 32b of the second rotational sealing ring 30b have different sliding areas, and the first rotational sliding surface. Although the sliding area of the surface 32a is larger than the sliding area of the 2nd rotation sliding surface 32b, it is not limited to this. By increasing the sliding area, the sealing characteristics are improved even when the pressure difference is large, such as the pump pressure and atmospheric pressure.

  The first stationary sealing ring 40a having the first stationary sliding surface 42a that slides on the first rotational sliding surface 32a of the first rotational sealing ring 30a is held by the first cup gasket 50a. The first stationary seal ring 40a and the second stationary seal ring 40b have different cross-sectional shapes, and the first cup gasket 50a and the second cup gasket 50b also have different cross-sectional shapes.

  The first stationary sealing ring 40a has a first stationary sliding surface 42a having substantially the same area as the first rotational sliding surface 32a of the first rotational sealing ring 30a. The inner diameter of the first stationary seal ring 40 a is larger than the outer diameter of the rotary shaft 6, and a gap is generated between the first stationary seal ring 40 a and the rotary shaft 6. This relationship is the same between the first rotary seal ring 30a and the rotary shaft 6.

  The first stationary sealing ring 40a is made of, for example, the same material as that of the first rotating sealing ring 30a, but is not necessarily made of the same material, and may be made of different materials.

  The second stationary sliding of the second stationary sealing ring 40b is performed in order to bring the first rotational sliding surface 32a of the first rotating sealing ring 30a into close contact with the first stationary sliding surface 42a of the first stationary sealing ring 40a. A coiled spring 70 is disposed between the first bellows 12a and the second bellows 12b in order to bring the second rotation sliding surface 32b of the second rotation sealing ring 30b into close contact with the surface 42b.

  As shown in FIG. 3, one end of the spring 70 in the axial direction contacts the bellows back surface portion 26a of the first mounting bracket 20a, and the other end contacts the bellows back surface portion (reference numeral omitted) of the second mounting bracket 20b. Touch. The spring force of the spring 70 is transmitted to the rotary sealing rings 30a and 30b via the bellows 16a of the respective bellows 12a and 12b, and presses them toward the stationary sealing rings 40a and 40b.

  A first cup gasket 50a is disposed between the first stationary seal ring 40a and the first housing 4a. The first cup gasket 50a can be compressed and held between the outer peripheral surface of the first stationary seal ring 40a and the stepped inner peripheral surface 5a formed near the outer surface of the first housing 4a. A first gasket body 52a is provided. A first inward convex portion 54a protruding inward in the radial direction is integrally formed at one end of the first gasket body 52a in the axial direction.

  The first inward convex portion 54a is continuous with the back surface located on the opposite side to the first stationary sliding surface 42a of the first stationary sealing ring 40a and the stepped inner peripheral surface 5a of the first housing 4a. It is possible to be compressed and held between the formed step surface 7a.

  The inner diameter d1 of the inner peripheral surface 57 of the inward convex portion 54a is preferably substantially the same as the inner diameter d2 of the inner diameter side joining position 15a with the first rotating seal ring 30a in the first bellows 12a. The pressure of the fluid sealed inside the pump chamber 8a acts on the inner diameter side joining position 15a of the first bellows 12a with the first rotary seal ring 30a. Therefore, the pressure balances with the fluid pressure acting on the back surface of the stationary sealing ring 40a located on the inner diameter side of the inner peripheral surface 57 of the inward convex portion 54a, and the adhesion force of the sliding surfaces 32a and 42a. Will improve. The inner diameters d1 and d2 may change depending on the pressure level of the sealed fluid.

  In the present embodiment, the radial thickness of the gasket body 52a is approximately the same as the radial thickness of the stationary seal ring 40a. In addition, the radial thickness of the gasket body 52a is twice or more larger than the axial thickness of the inward convex portion 54a. With this configuration, even when the pressure difference is large, such as the difference between the pump pressure in the pump chamber 8a and the atmospheric pressure in the oil chamber 10, the sealing characteristics are improved.

  As shown in FIG. 2, an outer peripheral convex portion 55 having an arcuate cross section may be formed on the outer peripheral surface of the cup gasket 50a. This outer peripheral convex portion 55 is elastically deformed and brought into close contact with the stepped inner peripheral surface 5a of the housing 4a shown in FIG.

  As shown in FIG. 2, an axial convex portion 46 is integrally formed on the inner peripheral portion of the front end surface 41 along the axis C of the stationary seal ring 40a, and a stationary sliding surface 42a is formed at the shaft end. It is formed. Moreover, the axial convex part 56 is integrally formed in the outer peripheral part of the front end surface 51 along the axial center C of the cup gasket 50a.

  The stationary sealing ring 40a is in close contact with the inner peripheral surface of the cup gasket 50a. The outer peripheral surface of the stationary sealing ring 40a is in close contact with the gasket body 52a of the cup gasket 50a, and the outer peripheral portion of the back surface of the stationary sealing ring 40a is in close contact with the inward convex portion 54a of the cup gasket 50a.

  The material of the cup gasket 50a is not particularly limited, but is made of a rubber material having excellent elasticity or a synthetic resin. The cup gasket 50a is not integrated with the stationary seal ring 40a by baking or the like, and can be separated.

  As shown in FIG. 2, a notch-shaped engaging recess 58 is formed in at least a part of the circumferential direction of the axial protrusion 56 of the cup gasket 50a. In the illustrated example, the engaging recess 58 is formed at only one location along the circumferential direction of the axial projection 56, but it may be formed at two locations at 180 ° symmetrical positions, or at approximately equal intervals. Alternatively, it may be formed at two or more places at unequal intervals.

  As shown in FIG. 3, the engaging concave portion 58 is engaged with an engaging convex portion 62 formed at the inner end of a disc-shaped washer 60, thereby preventing rotation of the cup gasket 50a. . The washer 60 is detachably fixed to the oil chamber side end surface of the housing 4a with a bolt 64 or the like. The inward end portion of the washer 60 is in close contact with the end face of the axial convex portion 56 of the cup gasket 50a, and suppresses the cup gasket 50a from protruding to the oil chamber 10 side.

  In the double mechanical seal device 2 according to the present embodiment, an inward convex portion 54a is formed on the gasket body 52a of the first cup gasket 50a. The inward convex portion 54a is held between the back surface of the stationary seal ring 40a and the stepped surface 7a of the housing 4a, and covers at least a part of the back surface of the stationary seal ring 40a. Therefore, the force based on the pressure of the fluid to be sealed acting on the back surface of the stationary seal ring 40a is smaller than that in the past, and the force is intended to increase the distance between the back surface of the stationary seal ring 40a and the stepped surface 7a of the housing 4a. Becomes smaller. Further, the washer 60 prevents the cup gasket 50a from moving in the axial direction with respect to the housing 4a.

  As a combined action of these, in the double mechanical seal device 2 of the present embodiment, the cup gasket 50a is moved from the outer peripheral surface of the stationary seal ring 40a to the oil chamber 10 by the pressure of the sealed fluid even when the size of the shaft diameter is increased. The possibility of coming off toward the surface is reduced, and the sealing performance is improved.

  In the double mechanical seal device 2, the cup gasket 50a, which is an elastic member, exists between the back surface of the stationary seal ring 40a and the step surface 7a, and fills the gap. For this reason, there is less possibility that foreign matter or the like in the slurry is caught between the back surface of the stationary seal ring 40a and the stepped surface of the housing 4a. As a result, the stationary sliding surface 42a of the stationary sealing ring 40a is not distorted, and the sealing performance is improved. Furthermore, damage to the stationary seal ring 40a due to foreign matters is reduced, and the durability of the stationary seal ring 40a is improved.

  Further, in this double mechanical seal device 2, even if the shaft diameter is increased, the cup gasket 50 a may come out from the outer peripheral surface of the stationary sealing ring 40 a toward the oil chamber 10 due to the pressure of the sealed fluid. Therefore, the stationary seal ring 40a and the cup gasket 50a are not joined but only need to be in pressure contact. Therefore, it is not necessary to bake the cup gasket 50a on the stationary seal ring 40a, and cracks of the stationary seal ring 40a can be effectively prevented.

  In the present embodiment, the cup gasket 50a and the washer 60 are formed with a fitting concave portion 58 and a fitting convex portion 62 for suppressing relative rotation, respectively. For this reason, it becomes possible to suppress relative rotation of the cup gasket 50a, and it is possible to suppress the stationary seal ring 40a from rotating together with the rotary seal ring 30a.

Second Embodiment As shown in FIG. 4, in the double mechanical seal device 2A according to the second embodiment of the present invention, only the configuration between the first cup gasket 50a1 and the washer 60 of the first mechanical seal device 2a1 is different. Other configurations are the same as those of the first embodiment, and common members are denoted by common reference numerals. Moreover, there exists an effect similar to 1st Embodiment except showing below. In the following description, only parts different from the first embodiment will be described, and descriptions of common parts will be omitted.

As shown in FIGS. 4 and 5, the cup gasket 50a1 is different from the cup gasket 50a shown in FIG. 2 in that the front end face 51 of the gasket body 52a1 is not formed with the axial convex portion 56. Instead, the outer peripheral side end surface of the disc-shaped case 80 is integrated with the front end surface 51 by bonding or baking.
This bonding or baking process is not essential and is appropriately applied depending on the application.

  The inner peripheral side end portion 82 of the disk-shaped case 80 comes into contact with the front end surface 41 of the stationary sealing ring 40a. The disc-shaped case 80 is made of metal or the like, and unlike a ceramic or the like, it is difficult to cause cracks. The outer diameter of the disk-shaped case 80 may be substantially the same as or smaller than the outer diameter of the front end face 51, and the inner diameter of the case 80 is located on the outer diameter side of the position where the axial protrusion 46 is formed. It may be substantially the same as or larger than the inner diameter of the front end surface 41.

  At least a part of the case 80 in the circumferential direction is formed with a notch-shaped engaging recess 58a1. In the illustrated example, the engaging recess 58a1 is formed at only one place along the circumferential direction of the case 80. However, it may be formed at two places at 180 ° symmetrical positions, or at substantially equal intervals or unequal. You may form in two or more places at intervals.

  As shown in FIG. 4, the engaging concave portion 58a1 is engaged with the engaging convex portion 62 formed at the inner end of the disc-shaped washer 60, thereby preventing the cup gasket 50a1 from rotating. .

  In the present embodiment, the inner peripheral side end 82 of the case 80 is locked to the front end surface 41 of the stationary seal ring 40a, so that the stationary seal ring 40a is restricted from moving axially toward the rotary seal ring 30a. It is. With this configuration, the distance between the back surface of the stationary seal ring 40a and the stepped surface 7a of the housing 4a can be kept substantially constant, and the compression acting on the inward convex portion 54a of the cup gasket 50a1. The force is also substantially constant, and the sealing performance is improved.

In addition, in this embodiment, you may comprise so that the inner peripheral side edge part 82 of case 80 may not engage with the stationary sealing ring 40a. In that case, the assembly of the stationary seal ring 40a, the case 80, and the cup gasket 50a1 is facilitated.
Here, the washer 60 and the case 80 are formed separately, but they may be formed as a single unit.

Third Embodiment As shown in FIG. 6, in the double mechanical seal device 2B according to the third embodiment of the present invention, the configuration between the first cup gasket 50a2 and the washer 60a2 of the first mechanical seal device 2a2 is different. The only difference is that the axial length of the first stationary seal ring 40a2 is increased, and the other configuration is the same as that of the first embodiment, and common members are denoted by common reference numerals. . Moreover, there exists an effect similar to 1st Embodiment except showing below. In the following description, only parts different from the first embodiment will be described, and descriptions of common parts will be omitted.

  As shown in FIG. 6, the cup gasket 50a2 is different from the cup gasket 50a shown in FIG. 2 in that the front end face 51 of the gasket body 52a2 is not formed with the axial convex portion 56. The front end face 51 of the cup gasket 50a2 is flush with the front end face 41 of the stationary sealing ring 40a2. In order to make such a configuration, the axial length of the gasket main body 52a2 is made longer than the length of the gasket main body 52a of the first embodiment, and the axial length of the stationary sealing ring 40a2 is set to the static sealing of the first embodiment. It is longer than the ring 40a.

  Further, the washer 60a2 of this embodiment has an inner diameter of the inner end portion 66 smaller than the inner diameter of the washer 60 of the first embodiment, and the inner end portion 66 is a front end surface of the stationary sealing ring 40a2. 41 abuts. The back surface of the washer 60a2 is also in contact with the front end surface 51 of the gasket body 52a2.

  By comprising in this way, it can restrict | limit that the stationary sealing ring 40a2 moves to an axial direction toward the rotation sealing ring 30a. Therefore, the distance between the back surface of the stationary seal ring 40a and the stepped surface 7a of the housing 4a can be kept substantially constant, and the compressive force acting on the inward convex portion 54a of the cup gasket 50a2 becomes substantially constant, Sealability is improved.

  Moreover, since the back surface of the washer 60a2 covers the entire front end surface 51 of the gasket body 52a2, it is possible to more effectively prevent the cup gasket 50a2 from being directed toward the oil chamber 10.

  In the present embodiment, the inner end portion 66 of the washer 60a2 may be engaged with the front end surface 41 of the stationary seal ring 40a2. In the present embodiment, the inner end 66 of the washer 60a2 may be configured not to engage with the stationary seal ring 40a2. In that case, the assembly of the stationary seal ring 40a and the cup gasket 50a2 becomes easy.

Fourth Embodiment As shown in FIG. 7, in a double mechanical seal device 2C according to a fourth embodiment of the present invention, between the first cup gasket 50a3 and the first stationary seal ring 40a3 of the first mechanical seal device 2a3. Only the configuration is different, and other configurations are the same as those of the first embodiment, and common members are denoted by common reference numerals. Moreover, there exists an effect similar to 1st Embodiment except showing below. In the following description, only parts different from the first embodiment will be described, and descriptions of common parts will be omitted.

  As shown in FIG. 7 and FIG. 8, the cup gasket 50a3 is different from the cup gasket 50a shown in FIG. 2 in the radial direction at the inner peripheral corner corresponding to the intersection of the gasket body 52a3 and the inward convex portion 54a. A fitting recess 53 that is recessed outward is formed. Further, an outer convex portion 43 that fits into the fitting concave portion 53 is formed on the outer peripheral surface on the back side of the stationary seal ring 40a3. By comprising in this way, the cup gasket 50a3 becomes further difficult to remove | deviate from the outer peripheral surface of the stationary sealing ring 40a3.

  The present invention is not limited to the above-described embodiment, and can be variously modified within the scope of the present invention.

  For example, in the above-described embodiment, the present invention is applied to the double mechanical seal device 2 including the first mechanical seal device 2a and the second mechanical seal device 2b. However, the present invention is the first mechanical seal device. The present invention can also be applied to a mechanical seal device composed only of the above. In the present invention, the second mechanical seal device 2b may be replaced with a seal device other than the mechanical seal device.

  Further, the structure of the mechanical seal device of the present invention is preferably applied to a mechanical seal device having a shaft diameter of 20 to 50 mm, but is not particularly limited, and is also applied to a large or small mechanical seal device. be able to.

2, 2A, 2B, 2C ... Double mechanical seal device 2a, 2a1, 2a2, 2a3 ... First mechanical seal device 2b ... Second mechanical seal device 4a ... First housing 4b ... Second housing 5a ... Stepped inner peripheral surface 6 ... Rotating shaft 7a ... Step surface 8a ... Pump chamber 8b ... Drive chamber 10 ... Oil chamber 12a ... First bellows 12b ... Second bellows 14a ... Cylindrical part 16a ... Bellow part 18a ... Tightening ring 20a ... First mounting bracket 20b ... 2nd mounting bracket 22a ... caulking part 24a ... inward convex part 26a for rotation prevention ... bellows back part 28a ... ring fitting part 30a ... 1st rotation sealing ring 30b ... 2nd rotation sealing ring 32a ... 1st rotation sliding surface 32b ... 2nd rotation sliding surface 40a, 40a2, 40a3 ... 1st stationary sealing ring 40b ... 2nd stationary sealing ring 42a ... 1st stationary sliding surface 42 2nd stationary sliding surface 50a, 50a1, 50a2, 50a3 ... 1st cup gasket 50b ... 2nd cup gasket 52a, 52a1, 52a2, 52a3 ... 1st gasket main body 54a ... 1st inward convex part 55 ... Outer peripheral convex part 56 ... Axial convex portion 57 ... Inner peripheral surface 58 ... Engaging concave portion 60, 60a2 ... Washer 62 ... Engaging convex portion 70 ... Spring 80 ... Disc-shaped case

Claims (6)

An elastic seal member attached to the outer periphery of a rotating shaft rotatable inside the housing so as to rotate together with the rotating shaft;
A rotary seal ring attached to the shaft end of the elastic seal member and rotating together with the elastic seal member;
A stationary sealing ring having a stationary sliding surface sliding with the rotating sealing ring;
A cup gasket held between the stationary seal ring and the housing;
A washer that prevents the cup gasket from moving axially relative to the housing;
The cup gasket is
A gasket body capable of being compressed and held between an outer peripheral surface of the stationary seal ring and a partial inner peripheral surface of the housing;
An inward convex portion that is molded integrally with the gasket body and projects radially inward,
The inward convex portion can be held by being compressed in the axial direction between a back surface located on the opposite side to the stationary sliding surface of the stationary sealing ring in the axial direction and the housing .
A mechanical seal device in which a disc-shaped case is interposed between the gasket body and the washer . The mechanical seal device according to claim 1, wherein an outer convex portion is formed on an outer peripheral surface of the stationary seal ring. An elastic seal member attached to the outer periphery of a rotating shaft rotatable inside the housing so as to rotate together with the rotating shaft;
A rotary seal ring attached to the shaft end of the elastic seal member and rotating together with the elastic seal member;
A stationary sealing ring having a stationary sliding surface sliding with the rotating sealing ring;
A cup gasket held between the stationary seal ring and the housing;
A washer that prevents the cup gasket from moving axially relative to the housing;
The cup gasket is
A gasket body capable of being compressed and held between an outer peripheral surface of the stationary seal ring and a partial inner peripheral surface of the housing;
An inward convex portion that is molded integrally with the gasket body and projects radially inward,
The inward convex portion can be held by being compressed in the axial direction between a back surface located on the opposite side to the stationary sliding surface of the stationary sealing ring in the axial direction and the housing .
A mechanical seal device in which an outer convex portion is formed on an outer peripheral surface of the stationary seal ring. The mechanical seal device according to any one of claims 1 to 3, wherein the stationary seal ring and the cup gasket are not joined but are simply press- contacted . The mechanical seal device according to any one of claims 1 to 4, wherein a fitting portion that suppresses relative rotation is formed in at least one of the gasket main body and the washer. The mechanical seal device according to any one of claims 1 to 5 , wherein an inner end portion in a radial direction of the washer regulates axial movement of the stationary seal ring.

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