JPS643016Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to the improvement of mechanical seals installed in water pumps, etc. of water-cooled engines.
More specifically, the present invention relates to improvements in counterfaces constituting mechanical seals.

The contact ring on the counter face slides in pressure contact with other sealing members to achieve sealing, and the cushion ring that holds the contact ring has sufficient sealing force to securely fix the contact ring. Must.

However, as shown in Fig. 1, conventionally, the fixing and sealing force relies only on the tension force between the contact ring 1 and the cushion ring 2 caused by being pressed into or press-fitted into other members and the friction coefficient of each material. When the pressure of the liquid to be sealed fluctuates or becomes high, liquid pressure 6 tends to be applied to both sides of the flange 2a of the cushion ring 2, as shown in FIG. Since the pressure applied to the contact ring 1 in contact with the contact ring 1 is changed and the contact ring 1 moves, the sealing force between the cushion ring 2 and the contact ring 1 is not only weakened, but also the sealing force is weakened as shown in FIG. There are disadvantages in that the sliding surface of the member with the friction ring 3 is adversely affected, and in the worst case, there is a risk of losing the sealing force, making it impossible to expect stable sealing performance.

The present invention eliminates the above-mentioned drawbacks and provides a mechanical seal counterface that can slide smoothly even when abnormal pressure occurs and maintain stable sealing performance for a long period of time.

As shown in FIG. 1, the present invention comprises a counter face consisting of a contact ring 1 and a cushion ring made of an elastic material such as synthetic rubber or synthetic resin that holds and fixes the contact ring 1; It is a mechanical seal that is made of a sealing member including a friction ring 3 that slides into contact with the rotary shaft 4 and the housing 5 of the shaft support of the rotary shaft 4 by the contact pressure of the two sliding surfaces. As shown in FIG.
The flange portion 2 is provided near the periphery by a concave groove ring, a convex ring, or a combination of the two concave and convex rings.
This is a mechanical seal structure in which a seal lip A is formed at at least one location on the periphery of the seal.

This structure always exhibits a strong and stable sealing force against fluid pressure.

That is, as shown in FIG. 3, when a flowing liquid is sealed, the liquid generates strong pressure or intermittent strong pressure, and also applies strong pressure to the cushion ring 2 formed of an elastic material. At this time, since the peripheral edge of the flange portion 2a of the cushion ring 2 has a plurality of seal lips A, the flange portion 2a
This seal lip A comes into pressure contact with both side members that are in contact with and exerts an effective sealing force. The shape of the seal lip A that exhibits this effect is such that the peripheral end surface of the flange portion 2a can receive liquid pressure, for example, as shown in FIG. A plurality of seal lips A are formed on the periphery of the flange 2a by providing concave groove rings near both inner sides of the periphery, and each concave groove ring is made to flexibly receive liquid pressure, and the seal lips A are expanded in the lateral direction to close the flange. A configuration in which the seal lip A is pressed against both side members where the portion 2a is in contact is preferable because it creates a shape that can be expected to have a stronger sealing force, but the seal lip A can also be formed by combining a concave groove ring or a protruding ring. There is no need to be particular about it.

As explained above, the present invention is an ideal mechanical seal that has a simple structure and exhibits a stable high sealing force for a long period of time against strong fluid pressure.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the structure of a mechanical seal. FIG. 2 is an enlarged partial sectional view showing the counterface of a conventional mechanical seal. FIG. 3 is an enlarged partial sectional view showing the counterface of the mechanical seal of the present invention. A... Seal lip, 1... Contact ring, 2... Cushion ring, 3... Friction ring.

Claims (1)

[Scope of utility model registration request] It consists of a counter face consisting of a contact ring and a cushion ring made of an elastic body that holds and fixes the contact ring, and a sealing member that slides into contact with the counter face. Therefore, in a mechanical seal that seals a rotating shaft and a housing of a shaft support of the rotating shaft; A mechanical seal characterized by having at least one ring-shaped seal lip near its periphery.