JPH0247320Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an improvement of a mechanical seal that seals the rotating shaft of a machine body such as a water pump.

[Conventional technology] Conventionally, in this type of mechanical seal,
As shown in FIG. 2, a rotating shaft 4 is inserted through a mating ring 3, which is a fixed ring fixed to the housing 1 side of the machine via a cap gasket 2. As a means to elastically press and force the seal ring 5, which is a rotating ring that rotates with the rotary ring, into sliding contact, the seal ring 5 is usually formed of a rubber bellows 6 that is in close contact with the rotating shaft 4, a casing 7 on the outer periphery of the seal ring 5, and a rubber bellows 6 that is in close contact with the rotating shaft 4. It has an integral structure with the drive ring 8, and is elastically pressed by the biasing force of the coil spring 10 inserted between the spring suppressing member 9, thereby causing the fluid to flow outward from the rotating shaft 4 side. Some devices have a structure that prevents leakage.

[Problems to be solved by the invention] However, in the mechanical seal of such a conventional structure, the so-called main body rotation type mechanical seal, the rubber bellows 6 that transmits the rotation of the rotating shaft 4 to the seal ring 5 is Since it is designed with a bent part 6a to withstand pressure from the back side, it is used in places where pressure is applied from the rotating shaft 4 side as described above, that is, where reverse pressure is applied. In some cases, the rubber bellows 6 is easily deformed, which causes damage to the rubber bellows 6 and causes leakage of sealing fluid.

[Purpose of the invention] The present invention was made under the above circumstances, and its purpose is to provide a mechanical seal that can reliably prevent damage to the rubber bellows due to back pressure. It's about doing.

[Means for solving the problems] In order to solve the above problems, the present invention has the following features:
A rotating ring that rotates together with the rotating shaft is elastically pressed and urged into sliding contact with a fixed ring fixed to the housing side of the aircraft body, and a rubber bellows is provided for transmitting the rotation of the rotating shaft to the rotating ring. In the mechanical seal, a reinforcing ring is provided at the bent portion of the rubber bellows.

[Function] That is, in the present invention, with the above configuration, a reinforcing ring is provided at the bent portion of the rubber bellows for reinforcement, so that pressure from the rotating shaft side is not applied to the rubber bellows. However, since the reinforcing ring can prevent the rubber bellows from deforming, it does not cause damage such as tearing of the rubber bellows, and as a result, there is no leakage of the sealing fluid, so it can be used for a long time. It becomes possible to maintain sealing performance.

[Example] Hereinafter, the present invention will be explained in detail with reference to an example shown in FIG. In the illustrated embodiment of the present invention, parts having the same structure as the conventional mechanical seal shown in FIG. 2 are denoted by the same reference numerals, and the explanation thereof will be omitted.

That is, as shown in FIG.
A reinforcing ring 11 such as an O-ring or a metal ring is provided on the bent portion 6a formed on the back side of the rubber bellows 6 that transmits the rotation of the rubber bellows 6 to the seal ring 5. This makes it possible to prevent the rubber bellows 6 from deforming due to pressure from the rotating shaft 4 side.

It should be noted that the present invention is not limited to the above-described embodiments in any way, and it goes without saying that various modifications can be made without changing the gist of the present invention.

[Effect of the invention] As is clear from the above explanation, according to the present invention, the fixed ring fixed to the housing side of the aircraft body has a
In a mechanical seal equipped with a rubber bellows that elastically presses a rotating ring that rotates together with a rotating shaft into sliding contact and transmits rotation of the rotating shaft to the rotating ring, a reinforcing ring is provided at a bent portion of the rubber bellows. Since the rubber bellows is reinforced with a ring, even if pressure from the rotating shaft side is applied to the rubber bellows, the reinforcing ring can prevent the rubber bellows from deforming, thereby preventing damage such as tearing of the rubber bellows. Since there is no leakage of the sealing fluid, the sealing performance can be maintained for a long period of time, which is an excellent effect.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of a main part showing an embodiment of a mechanical seal according to the present invention, and FIG. 2 is a schematic cross-sectional view of a main part showing a conventional mechanical seal. 1... Body housing, 3... Fixed ring (mating ring), 4... Rotating shaft, 5... Rotating ring (seal ring), 6... Rubber bellows, 6a...
Bent portion, 9... Spring suppressing member, 10...
Coil spring, 11... Reinforcement ring.

Claims (1)

[Scope of utility model registration request] A rotating ring that rotates together with the rotating shaft is elastically pressed and urged into sliding contact with a fixed ring fixed to the housing side of the aircraft body, and a rubber bellows is provided for transmitting the rotation of the rotating shaft to the rotating ring. A mechanical seal characterized in that a reinforcing ring is provided at a bent portion of the rubber bellows.