JPH0587251A - Mechanical seal provided with draining function - Google Patents

Abstract

PURPOSE:To remove a drain board and promote the shortening of a turning shaft by imparting a draining function to a mechanical seal itself available in various pumps. CONSTITUTION:In a mechanical seal 1 being made up of sealing a fixed ring 3 at the housing side of a machine body by pressing a seal ring 4 at the side of a turning shaft 10 with one end of a coil spring 8 set up around this turning shaft, a draining part, consisting of a tubular part 9a extending in parallel with the turning shaft 10 and a flangelike part 9b extending in the radial direction, is solidly formed at the outside of a spring holder 9 holding the other end of the coil spring 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical seal used in various pumps, and more particularly to a mechanical seal which can prevent water from leaking to the rotary shaft side.

[0002]

2. Description of the Related Art Conventionally, a mechanical seal used in a water pump or the like has a coil spring 11 as shown in FIG.
Is provided with a spring holder 12 for holding
Separately from the pulling holder 12, a drain plate 15 for preventing water leaking from the pump chamber 13 side from entering the rotary bearing 14 side is provided at a position appropriately separated from the spring holder 12 to the rotary bearing 14 side. There is. The draining plate 15 is a donut-shaped disc, the inner diameter of which is the rotation shaft 1.
The rotary bearing 1 is fixed to 6 and the rotation of the rotary shaft 16 causes the centrifugal force to scatter water leakage from the pump chamber 13 side.
Prevents leakage of water to the 4th side.

However, since the drainage plate 15 is provided, the length of the rotary shaft 16 is inevitably extended, and the number of parts is increased, which hinders downsizing of the pump and the like. Further, since it is composed of a large number of parts, it requires skill to manufacture a pump and the like, and requires a long working time, which is a great obstacle to the production efficiency of the pump and the like.

[0004]

SUMMARY OF THE INVENTION In view of the above points, the present invention makes various investigations on the shape of a spring holder in a mechanical seal and makes improvements.
By adding a draining function to this spring holder, it is possible to remove the draining plate, and as a result, it is possible to reduce the number of parts and realize the downsizing of pumps, etc., and also to reduce the production cost and production efficiency. It is aimed at improving.

[0005]

According to the present invention, a seal ring on a rotary shaft is sealed against a fixed ring on a housing side of a machine body by pressing one end of a coil spring arranged around the rotary shaft. In the mechanical seal having the structure, a water draining portion including a cylindrical portion extending parallel to the rotation axis and a flange portion extending in a radial direction is integrally formed outside a spring holder that holds the other end of the coil spring. It is characterized by doing.

[0006]

In the present invention, even if water leaks from the seal on the pump chamber side, the spring holder is integrally formed with a draining portion having a draining function.
The water leakage is scattered by the centrifugal force caused by the rotation of the spring holder, and the water leakage does not enter the bearing portion of the rotating shaft.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the drawings. 1 is a cross-sectional view of a mechanical seal 1 according to a first embodiment of the present invention, which is a gasket 2, a fixing ring 3, a seal ring 4, a bellows 5, a case 6,
It is composed of a drive ring 7, a coil spring 8, a spring holder 9, and the like. In the figure, reference numeral 10 is a rotation axis.

The gasket 2 and the fixing ring 3 are integrated with an appropriate adhesive, and in this state they are fixed to a housing (not shown) of the machine body, and are in a floating state with the rotary shaft 10. Both the fixed ring 3 and the seal ring 4 are formed of a SiC alloy or the like, and the facing end faces are in sliding contact with each other. The seal ring 4 is integrated with the bellows 5 with an appropriate adhesive and inserted into the case 6.
The inner diameter portion of the bellows 5 is fixed to the rotary shaft 10 by press fitting, while the inner diameter portion of the seal ring 4 is in a floating state.

The spring holder 9 according to the present invention is
As shown in FIG. 1, there is provided a cylindrical portion 9a of an appropriate length, which projects parallel to the rotary shaft 10 toward the pump chamber side, at the outer peripheral edge of the disk portion, and thereby the coil spring 8 is formed. keeping. A collar-shaped portion 9b is integrally formed on the end surface of the tubular portion 9a so as to project outwardly (that is, in the radial direction of the spring holder 9) with an appropriate length so as to be substantially parallel to the disk portion of the spring holder 9. It is formed in a special way. That is, the tubular portion 9a and the collar-shaped portion 9b form a draining portion of the spring holder 9. Further, a hole (reference numeral omitted) through which the rotary shaft 10 penetrates is formed in the center of the spring holder 9, and the hole is fixed to the stepped portion 10a of the rotary shaft 10 through this hole. A coil spring 8 that presses the seal ring 4 toward the fixed ring 3 side is mounted between the inner surface of the spring holder 9 (that is, the side surface facing the pump chamber side) and the case 6. Due to the biasing force of the coil spring 8, both end surfaces of the fixed ring 3 and the seal ring 4 are brought into slidable contact with each other to perform a sealing function.

In the mechanical seal 1 having the water draining function according to the above structure, even if water leaks from the seal on the pump chamber side, the flange portion 9b of the spring holder 9 is rotated by the rotation of the rotary shaft 10 to cause the spring holder to rotate. 9
Since it rotates integrally with the water, the water leakage is scattered by the centrifugal force of the collar-shaped portion 9b, and the water leakage does not enter the bearing portion of the rotating shaft 10.

A second embodiment of the spring holder 9 having the above construction is shown in FIG. The spring holder 9'shown in FIG. 2 has a coil spring 8 on a donut-shaped disc portion.
A cylindrical portion 9a 'for holding is projected in parallel to the pump chamber side along the rotating shaft 10 by a suitable length. Then, the outer base of the tubular portion 9a ', that is, the collar-shaped portion 9b' continuous on the extension line of the disk portion of the spring holder 9 ', is appropriately extended outward (that is, in the radial direction of the spring holder 9'). It is projected with a size. The other members of the mechanical seal 1 are similar to those of the embodiment shown in FIG.
Detailed description and additional symbols are omitted.

In the mechanical seal 1 according to the second embodiment, as in the first embodiment, the collar-shaped portion 9b 'of the spring holder 9'is rotated by the rotation of the rotary shaft 10.
As it rotates together with the spring holder 9 ',
Even if there is water leakage, the water leakage will be scattered by the centrifugal force of the collar-shaped portion 9b ′ and will not enter the bearing portion of the rotary shaft 10.

[0013]

As described above, according to the present invention, since the shape of the spring holder is changed to integrally form the draining portion having the draining function, the draining plate which is a separate member in the related art is deleted. It is possible to reduce the number of parts in various pumps that use mechanical seals. As a result, the axial length of the rotary shaft can be shortened, and the pump or the like can be made smaller or more compact. Further, the work time can be shortened by reducing the number of parts, and the production efficiency can be improved. Further, it can be provided with a simple structure and at a low cost, so that the manufacturing cost of the pump and the like can be reduced, which is very effective as a mechanical seal of this type.

[Brief description of drawings]

FIG. 1 is a sectional view of a mechanical seal showing a first embodiment of the present invention.

FIG. 2 is a sectional view of a mechanical seal showing a second embodiment of the present invention.

FIG. 3 is a cross-sectional view when a conventional mechanical seal and a conventional draining plate are used in a water pump.

[Explanation of symbols]

 1 Mechanical seal 3 Fixed ring 4 Seal ring 8 Coil spring 9 Spring holder 9'Spring holder 9a Cylindrical part 9b Collar-shaped part 9a 'Cylindrical part 9b' Collar-shaped part 10 Rotating shaft

Claims (1)

[Claims] 1. A mechanical structure in which a seal ring 4 on the rotary shaft 10 side is sealed against a fixed ring 3 on the housing side of the machine body by pressing one end of a coil spring 8 arranged around the rotary shaft 10. In the seal 1, on the outside of the spring holder 9 that holds the other end of the coil spring 8, a draining portion including a tubular portion 9a extending parallel to the rotating shaft 10 and a flanged portion 9b extending in the radial direction is provided. A mechanical seal with a draining function, characterized by being formed integrally.