JPH04127465U - mechanical seal - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent the deterioration of the axial operability of the stationary side sliding ring 50 due to the accumulation of slurry B on the wetted side of the packing, and to provide a sealing sliding when the fluid pressure in the pressurizing chamber 82 drops. Compensate the surface pressure of part S. [Structure] A stationary side sliding ring 50 that presses and slides into contact with the rotating side sliding ring 10, an annular pressurizing chamber 82 recessed in the axial direction in the housing 80, and a stationary side sliding ring 50 at one end. The retainer 60 is provided with a retainer 60 whose other end is inserted into the pressurizing chamber 82 airtightly and movably in the axial direction through a packing, and one end 101 is connected to the housing 80 as the packing.
A rubber spring 100 is used, the other end 102 of which is pressed and fixed to the retainer 60, and which is biased with a spring load in the axial direction.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is useful as a shaft sealing device for rotating equipment that handles liquids containing slurry. Therefore, it is a mechanism with a structure in which the surface pressure on the sealed sliding surface of the sliding ring is given by fluid pressure. Regarding Lucille.

0002

[Conventional technology]

Conventionally, as a type of mechanical seal, as shown in Fig. 2, a sliding ring on the rotating side has been used. 10 and the stationary side sliding ring 50 on the sealing sliding surface S of the fluid other than the liquid to be sealed A. A structure in which the pressure is applied is known.

0003 That is, the rotating side sliding ring 10 made of ceramic is a sliding ring mounted on the shaft 20. It is airtightly fitted and fixed to the flange portion 31 of the tube 30 via a gasket 40. A ceramic member contacts the rotating sliding ring 10 in the axial direction to form a sealed sliding portion S. The stationary side sliding ring 50 made by Mick has a flange portion 61 formed at one end of the retainer 60. is fitted and fixed to the retainer 60 through a gasket 70, and the cylindrical shape at the other end of this retainer 60 The portion 62 is recessed in the housing 80 in the axial direction and is provided through the pressure supply hole 81 (not shown). An annular pressure chamber 82 to which fluid pressure is applied from an external pressure source is movable in the axial direction. is inserted into.

0004 The inner and outer peripheral surfaces of the cylindrical portion 62 of the retainer 60 and the housing in the pressurizing chamber 82 A sliding packing 90 such as an O-ring is interposed between the opposing circumferential surface of each ring 80. This seals the pressurizing chamber 82. Further, the retainer 60 has a cylindrical shape. A hole 63 formed on the back side of the portion 62 and a hole 63 formed in the housing 80 are inserted into the pressurizing chamber 82. Rotation is prevented by engagement with a pin 83 that protrudes in the axial direction.

[0005]

[Problem that the idea aims to solve]

This mechanical seal transfers fluid pressure applied within the pressurizing chamber 82 to the retainer 60. When the back surface of the cylindrical portion 62 receives pressure, the stationary side sliding ring 50 is urged in the axial direction. Then, a constant surface pressure is applied to the sealing sliding part S at all times, which is necessary for sealing the liquid A to be sealed on the outer circumferential side. However, according to the above conventional structure, the liquid A to be sealed contains a large amount of slurry. If the cylindrical portion 62 of the retainer 60 and the opposing peripheral surfaces of the pressurizing chamber 82 When slurry B accumulates on the wetted side of the sliding packing 90 interposed between the Since the sliding performance between the retainer 90 and the retainer 60 is inhibited, the axial vibration of the shaft 20 The ability of the stationary sliding ring 50 to follow the axial displacement of the rotating sliding ring 10 decreases, and There was a problem that leakage occurred from the sealing sliding part S.

[0006] In addition, if a malfunction occurs on the external pressure source side or the accumulated slurry B For some reason, such as wear of the sliding packing 90, the fluid pressure in the pressurizing chamber 82 becomes extremely high. If the pressure decreases or becomes impossible to apply pressure, the surface pressure necessary for sealing cannot be obtained on the sealing sliding part S. There was a risk that a large amount of leakage would occur.

[0007] Therefore, in view of the above-mentioned problems, the present invention was developed to prevent the sliding ring on the stationary side from being damaged due to the accumulation of slurry. Prevents a decrease in axial operability and compensates for the surface pressure on the sealed sliding part when fluid pressure in the pressurized chamber drops. This was done with the aim of doing so.

[0008]

[Means to solve the problem]

In order to solve the above problems, the present invention has developed a stationary side sliding ring that is pressed and slid into contact with a rotating side sliding ring. a moving ring, an annular pressurizing chamber recessed in the housing in the axial direction, and the stationary side slide at one end. While holding the moving ring, the other end is airtightly and axially connected to the pressurizing chamber through a packing. In the mechanical seal comprising a movably inserted retainer, the pad is One end is press-fitted to the housing and the other end is press-fitted to the retainer. , which uses a rubber spring that is biased with a spring load in the axial direction.

[0009]

[Effect]

According to the above configuration, one end is press-fitted and fixed to the housing, and the other end is press-fitted and fixed to the retainer. Rubber spring as a packing with a fixed spring load in the axial direction is not due to sliding with the retainer or housing, but due to deformation in the axial direction. The retainer and the stationary side sliding ring integrated with the retainer are allowed to operate in the axial direction, and The stationary sliding ring slides against the rotating sliding ring due to the reaction force against axial deformation. Apply surface pressure.

0010

【Example】

The mechanical seal shown in FIG. 1 as an embodiment of the present invention has a cylindrical retainer 60. A rubber spring 100 is interposed between the outer peripheral surface of the portion 62 and the housing 80. The rest of the configuration is the same as the conventional example shown in FIG. They are shown with numbers, and their explanations are omitted.

[0011] The rubber spring 100 has a cross section extending obliquely with respect to the axis. One end 101 on the large diameter side is connected to the outer peripheral side opening of the pressurizing chamber 82 of the housing 80. It is fitted into the fitting recess 84 formed around the edge of the mouth and fixed by pressure, and it is stationary. The other end 102 on the small diameter side extending toward the side sliding ring 50 is located at the rear inner diameter position of the flange portion 61. is fitted into the fitting recess 64 formed on the outer peripheral surface of the cylindrical portion 62 of the retainer 60 and pressurized. The housing 80 and the retainer 60 are compressed and sheared as appropriate between the housing 80 and the retainer 60. It has been interposed in a state of Note that the inner peripheral surface of the cylindrical portion 62 and the pressurizing chamber 82 are A sliding packing 9 such as an O-ring is inserted between the opposing peripheral surfaces of the housing 80 as in the conventional case. 1 is sealed.

0012 According to this embodiment, the liquid contact side of the rubber spring 100 is filled with the liquid A to be sealed. Even if Rally B accumulates, this rubber spring 100 will not slide on the retainer 60. This allows the retainer 60 to operate in the axial direction through compression and shear deformation. Therefore, the rotation side sliding ring 10 remains stationary against axial displacement due to the axial vibration of the shaft 20. The followability of the side sliding ring 50 is not inhibited by the accumulation of slurry B.

[0013] Further, the rubber spring 100 itself reacts against the deformation in the compression and shear directions. Due to the force, there is a spring load in the axial direction on the stationary side sliding ring 50, so in the unlikely event that If some malfunction occurs such as a failure of an external pressurizing device, the fluid pressure in the pressurizing chamber 82 may decrease. Even if it becomes impossible to apply It is possible to ensure good sealing performance.

[0014] In addition to having a reaction force against the deformation, the rubber packing 100 also has the following characteristics: Substantially expands the pressure receiving area of the retainer 60 against the fluid pressure of the pressurizing chamber 82 Therefore, the pressure applied from the outside can be reduced.

[0015] Note that the present invention is not limited to the illustrated embodiment. For example, the illustrated embodiment Here, a rubber spring 100 is provided on the outer circumferential side of the retainer 60, and a sliding part is provided on the inner circumferential side. Although the structure is such that the sealing ring 91 is interposed, the liquid A to be sealed is If the sliding packing 91 is present on the inner circumferential side of the sealing sliding portion S, the sliding packing 91 may be replaced with A similar rubber spring may be provided on the inner circumferential side of the retainer 60, or a rubber spring may be provided on both the inner and outer circumferences. A rubber spring may be provided on either side.

[0016]

[Effect of the idea]

As described above, according to the mechanical seal of the present invention, the retainer and the retainer are integrated. The axial movement of the stationary sliding ring creates a seal between the pressurized chamber of the housing and the retainer. This is allowed due to the axial deformation of the rubber spring used as a packing. This prevents the axial operability of the stationary side sliding ring from decreasing due to slurry accumulation. This eliminates problems such as leakage from sealed sliding parts. In addition, since the rubber spring itself has a spring load in the axial direction, it Even if it becomes impossible to apply fluid pressure to the pressurized chamber due to equipment failure, etc., the seal will remain sealed. By compensating the surface pressure of the sliding part, it is possible to prevent the occurrence of leakage.

[Brief explanation of drawings]

FIG. 1 is a half-sectional view showing an embodiment of the present invention.

FIG. 2 is a half-sectional view showing a conventional example.

[Explanation of symbols]

10 Rotating side sliding ring 20 Shaft 50 Stationary side sliding ring 60 retainer 62 Cylindrical part 64, 84 Fitting recess 80 Housing 82 Pressurized chamber A Liquid to be sealed S Sealed sliding part

Claims (1)

[Scope of utility model registration request] Claim 1: A stationary side sliding ring that presses and slides into contact with a rotating side sliding ring, an annular pressurizing chamber recessed in the axial direction in a housing, and one end of which holds the stationary side sliding ring. and a retainer whose other end is inserted into the pressurizing chamber airtightly and movably in the axial direction via a packing, wherein the packing has one end fixed to the housing by pressure contact and the other end fixed to the retainer by pressure contact. A mechanical seal characterized by the use of a rubber spring that is biased with a spring load in the axial direction.