JPH0611045A - Mechanical seal - Google Patents

Abstract

PURPOSE:To prevent rotation of the seal ring of a mechanical seal by forming opposing projecting and recessed parts at least on one side between a casing and packing or between the seal ring and packing. CONSTITUTION:In a mechanical seal 15, a proper number of opposing projecting and recessed parts are formed on the contact faces between a seal ring 24 and the outer circumferential flange part 28 of packing 26. Namely, a proper number of projecting parts 41 formed on the seal ring 24 are fitted into the same number of recessed parts 42 formed on the outer circumferential flange part 28. Further, opposing projecting and recessed parts 45 are properly formed on the contact part between a casing 25 and the outer circumferential flange part 27 of the packing 26. Namely, a proper number of projecting parts 46 formed on a part of the casing 25 so as to project on the inner circumferential side are engaged with the same number of recessed parts 47 formed on a part of the outer circumferential flange part 27 and a retainer 29 so as to be recessed on the inner circumferential side. It is satisfied to form at least one side of the projecting and recessed parts 40, 45, but to form both sides naturally.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical seal and is used, for example, in a water pump or the like.

[0002]

2. Description of the Related Art As a prior art relating to the present invention, there is a "mechanical seal" disclosed in, for example, Japanese Utility Model Laid-Open No. 2-31637. This conventional technique will be described with reference to FIG. 6. A shaft 72 is supported by a water pump housing 71 via a bearing (not shown), and a pump chamber 73
A mechanical seal 75 is provided between the water pump housing 71 and the shaft 72 in order to prevent water from entering the bearing chamber 74. A sleeve 76 is fitted on the shaft 72, and a floating sheet 7 serving as a rotating ring is provided on the outer circumference of the sleeve 76 with a cushioning rubber 77 interposed therebetween.
8 is provided. A seal ring 79, which is a fixed ring, is brought into sliding contact with the floating sheet 78.
Is attached to a casing 80 fixed to the water pump housing 71 via a bellows-shaped packing 81.
A spring 86 is elastically mounted between a pair of retainers 84 and 85 bent in an L-shaped cross section between the outer peripheral brim portions 82 and 83 at both ends of the packing 81, and the seal ring 79 is pressed against the floating sheet 78 by the spring 86. Further, the extending portion 88 of the casing 80 is engaged with the engaging recess 87 formed in the inner diameter portion of the seal ring 79 to prevent the rotation.

The illustrated right end surface of the seal ring 79, the illustrated left end surface of the packing 81, and the illustrated left end surface of the casing 80 and the illustrated right end surface of the packing 81 are not adhered, and the retainer 85 on the inner peripheral surface of the packing 81 is provided. The rib 89 is formed at a position corresponding to the inner diameter bent portion to ensure stable sealing performance. The rib 89 may be arranged at a position corresponding to the inner diameter bent portion of the retainer 84 on the inner peripheral surface of the packing 81.

However, the seal ring 79 and the packing 8
Since there is no adhesiveness between the 1st, slippage occurs between the 2nd,
As the seal ring 79 tries to rotate together with the floating sheet 78, the engagement recess 87 of the carbon seal ring 79 may be worn by the extension 88 of the metal casing 80. Further, since the casing 80 and the packing 81 are not adhered to each other, slippage similarly occurs between the casing 80 and the packing 81, the packing 83 and the seal ring 79 try to rotate together with the floating sheet 78, and the engagement recess 87 of the seal ring 79 causes the casing 87 to move. The extension 88 of 80 may cause wear.

[0005]

Therefore, according to the present invention,
Preventing the rotation of the seal ring of the mechanical seal is a technical issue.

[0006]

[Constitution of the invention]

[0007]

The technical means of the present invention taken to solve the above-mentioned technical problems of the present invention include a casing, a seal ring supported by packing the casing, and a seal. In a mechanical seal having a floating sheet that slides in contact with the ring and a spring that is arranged on the outer peripheral portion of the packing and presses the seal ring toward the floating sheet, at least between the casing and the packing and between the seal ring and the packing. On the one hand, it means that the concavo-convex portions facing each other were formed.

[0008]

According to the above-mentioned technical means of the present invention, the uneven portion formed between the casing and the packing prevents relative rotation between the casing and the packing, and is formed between the seal ring and the packing. The formed uneven portion prevents relative rotation between the seal ring and the packing.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the technical means of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, a shaft 12 is rotatably supported by a water pump housing 11 via a bearing 13. An impeller 14 is fixed to the left end of the shaft 12 in the drawing, and a pulley (not shown) is fixed to the right end of the shaft 12 to obtain a driving force from an external driving source (not shown). A mechanical seal 15 disposed between the water pump housing 11 and the shaft 12 allows a bearing chamber 16 in which the bearing 13 is located and an impeller 14 to be located.
Is partitioned from the pump chamber 17 in which is located.

The water pump 10 is constructed as described above.

The mechanical seal 15 will be described in detail with reference to FIG. 2. A sleeve 21 is fitted on the outer circumference of the shaft 12 (not shown in FIG. 2), and a rotary ring is provided on the outer circumference of the sleeve 21 via a buffer rubber 22. The floating sheet 23 is provided. The floating sheet 23 is made of, for example, ceramics. A seal ring 24, which is a fixed ring, is in sliding contact with the floating seat 23. The seal ring 24 is not shown in the water pump housing 11 (not shown in FIG. 2).
The bellows-like packing 2 is attached to the casing 25 fixed to the
It is attached through 6. This seal ring 24 is
For example, it is formed of carbon. A spring 31 is elastically mounted between a pair of retainers 29 and 30 that are bent in an L-shaped cross section between the outer peripheral flanges 27 and 28 at both ends of the packing 26, and the seal ring 24 is pressed against the floating sheet 23 by the spring 31. .

Therefore, the sleeve 21, the cushioning rubber 22 and the floating seat 23 rotate integrally with the shaft 12, and the seal ring 24, the casing 25, the packing 26, the retainers 29, 30 and the spring 31 are stationary together with the water pump housing 11. It does not rotate.

As shown in FIG. 3, the contact surface between the illustrated left end surface of the seal ring 24 and the illustrated right end surface of the outer peripheral flange portion 28 of the packing 26 is provided with a suitable number of concavo-convex portions 40. That is, an appropriate number of convex portions 41 formed on the left end surface of the seal ring 24 in the drawing are fitted into the same number of concave portions 42 formed on the right end surface of the outer peripheral flange portion 28 in the drawing. Instead of the convex portion 41 and the concave portion 42, saw blade-shaped convex portions 43 and concave portions 44 are formed on both the illustrated left end surface of the seal ring 24 and the illustrated right end surface of the outer peripheral flange portion 28 as shown in FIG. May be.

Further, as shown in FIG. 5, the casing 25
An appropriate number of concavo-convex portions 45 are formed at a contact portion between the packing 26 and the outer peripheral flange portion 27. That is, an appropriate number of protrusions 46 formed so as to project to the inner peripheral side in a part of the casing 25, and an equal number of convex portions 46 formed in a part of the outer peripheral flange 27 and the retainer 29 so as to be recessed toward the inner peripheral side. Recess 47
Is engaged with.

Here, the uneven portion 40 and the uneven portion 45 are at least those depending on the possibility of sliding between the seal ring 24 and the packing 26 and the possibility of sliding between the casing 25 and the packing 26. It is sufficient if one is formed, but of course both may be formed. The left end surface of the seal ring 24 in the drawing and the outer peripheral flange portion 2 of the packing 26 are
The contact surface of 8 with the right end surface in the figure and the contact portion of the casing 25 and the outer peripheral flange portion 27 of the packing 26 have a non-adhesive structure.

An annular rib 51 is formed at the contact portion of the packing 26 with the seal ring 24 on the horizontal plane in the drawing, and an annular rib 52 is formed at the contact portion between the outer peripheral flange 27 of the packing 26 and the casing 25. 53 is formed.

The operation of the mechanical seal having the above configuration will be described. The mechanical seal 15 prevents water from entering the bearing chamber 16 from the pump chamber 17 when the water pump 10 operates. That is, although the floating seat 23 rotates with the shaft 12, the seal ring 24 is pressed against the floating seat 23 by the spring 31 and is in sliding contact therewith. Therefore, the floating seat 23 and the seal ring 24 rotate relative to each other, and the sliding contact surface between them seals between the pump chamber 17 and the bearing chamber 16.

At this time, since the rotational force of the shaft 12 is also applied to the seal ring 24 via the floating sheet 23, unnecessary relative rotation is caused between the seal ring 24 and the packing 26 and between the casing 25 and the packing 26. Can occur. Now, if it is known from various tests that relative rotation is likely to occur between the seal ring 24 and the packing 26, by forming the uneven portion 40, the seal ring 24 cannot rotate relative to the packing 26, and the seal Ring 24 does not rotate. Further, if it is known from various tests that relative rotation is likely to occur between the casing 25 and the packing 26, the unevenness 45 prevents the seal ring 24 and the packing 26 from rotating relative to the casing 25. The seal ring 24 and the packing 26 do not rotate. Further, if it is known by various tests that relative rotation is likely to occur both between the seal ring 24 and the packing 26 and between the casing 25 and the packing 26, both the uneven portions 40 and 45 may be formed. Good.

The annular ribs 51, 52 and 53 contribute to improving the sealing performance at each part.

[0021]

As described above, in the mechanical seal of the present invention, the contact portion between the casing and the packing and the contact portion between the seal ring and the packing are provided with the concavo-convex portion facing at least one of them, if necessary. Therefore, relative rotation at each contact portion can be prevented. Therefore, rotation of the seal ring can be prevented, and deterioration of the sealability due to rotation of the seal ring can be prevented.

[Brief description of drawings]

FIG. 1 shows a configuration diagram of a water pump according to an embodiment of the present invention.

FIG. 2 shows an enlarged cross-sectional view of the mechanical seal in FIG.

FIG. 3 shows an AA view in FIG.

FIG. 4 shows an AA view of the modified embodiment in FIG.

FIG. 5 shows a BB view in FIG.

FIG. 6 shows a cross-sectional view of a prior art mechanical seal.

[Explanation of symbols]

 15 mechanical seal, 23 floating sheet, 24 seal ring, 25 casing, 27 spring, 28 packing, 40, 45 uneven parts.

Claims (1)

[Claims] 1. A casing, a seal ring supported by the casing via a packing, a floating sheet slidably contacting with the seal ring, and an outer peripheral portion of the packing, wherein the seal ring is directed toward the floating sheet. A mechanical seal having a spring that presses by pressing, wherein a concavo-convex portion is formed at least between the casing and the packing and between the seal ring and the packing.