JPH07780Y2 - mechanical seal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an improvement in a mechanical seal used as a shaft sealing device for shaft-sealing a rotary shaft portion of a machine body such as a water pump for an automobile.

[Prior Art] Conventionally, in this type of mechanical seal, as illustrated in FIG. 2, a rotary shaft 3 which is inserted into an inner circumference of a fixed housing 2 of a machine body and has a pump impeller mounted at a tip thereof.
When axially sealing the mating ring 5, a mating ring 5 made of a material such as ceramic as a rotary ring is fitted and fixed to the rotary housing 1 formed on the impeller via a cup gasket 4 while the mating ring 5 is fixed. A rubber bellows, which is a cartridge type, is slidably in contact with a seal ring 6 made of a carbon material that is a fixed ring, and the seal ring 6 is fixed to the fixed housing 2 side of the machine body in an outer cylindrical casing 7. 8, some of them have a structure in which they are axially sealed by being pressed and urged in the axial direction via a coil spring 9.

[Problems to be Solved by the Invention] However, in the mechanical seal having such a conventional structure, the sliding surfaces A of the mating ring 5 and the seal ring 6 are prevented from each other due to the friction due to the rotational sliding. Heat is generated, and in particular, the vicinity of the outer circumference of the sliding surface A is cooled and lubricated by being in contact with the fluid (seal fluid) to be fed by the rotation of the impeller, but the vicinity of the inner circumference of the sliding surface A is
Since the sealing fluid has a small cooling effect and a lubricating effect and the sliding material such as carbon used for the seal ring 6 has a low thermal conductivity, the heat generation causes the temperature to increase toward the inner peripheral side.

For this reason, during rotation and sliding of the mechanical seal, a substance in the seal fluid is deposited due to heat between the sliding surfaces, and the sliding surface A
However, there is a problem in that it easily adheres to and is deposited on the surface of the sliding surface, which causes the sliding surfaces to be spread apart and reduces the sealing performance.

[Object of the Invention] The present invention has been made under the above circumstances. The object of the present invention is to deposit and deposit the substance in the sealing fluid between the sliding surfaces during rotation and sliding. (EN) Provided is a mechanical seal capable of preventing the occurrence of the above.

[Means for Solving the Problems] In order to solve the above problems, according to the present invention, a mating ring fixed to a rotation side housing is slidably contacted with a seal ring fixed to a fixed side housing of an airframe. In the mechanical seal, the inner diameter portion of the seal ring is provided with a heat radiation ring whose one end reaches the inside of the sliding surface with the mating ring and which has a higher thermal conductivity than the seal ring. It is a thing.

[Operation] According to the present invention, the sliding heat generated on the inner circumferential side of the sliding surface, which is less susceptible to the cooling action of the seal fluid in the outer circumferential space of the sliding surface,
Since it is satisfactorily released by the heat radiation ring provided in the inner diameter portion of the seal ring, the occurrence of a temperature gradient on the sliding surface such that the inner circumferential side of the sliding surface becomes hot is prevented or mitigated.

[Embodiment] The present invention will be described below with reference to an embodiment shown in FIG. In the illustrated embodiment according to the present invention, the same parts as those of the conventional mechanical seal shown in FIG. 2 are designated by the same reference numerals, and the description thereof will be omitted.

That is, according to the present invention, as shown in FIG. 1, a heat radiating ring 10 made of a material having a high thermal conductivity such as copper is integrally provided on the inner diameter portion 6a of the seal ring 6, and the heat radiating One end of the ring 10 reaches the inside of the sliding surface A near the inner diameter.

[Advantage of the Invention] As is clear from the above description, according to the present invention, since the heat radiation ring is provided in the inner diameter portion of the seal ring,
According to the present invention, the sliding heat near the inner circumference of the sliding surface, which is less likely to be cooled by the sealing fluid on the outer circumference side of the sliding surface, is effectively radiated by the heat radiation ring provided in the inner diameter portion of the seal ring. Therefore, the occurrence of a temperature gradient on the sliding surface such that the inner circumferential side of the sliding surface becomes high temperature is prevented or mitigated, and as a result, the substance in the sealing fluid near the inner circumference of the sliding surface is deposited and deposited. Effectively prevents the occurrence of leakage due to
It has an excellent effect that high sealing performance can be maintained for a long period of time.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a mechanical seal according to the present invention, and FIG. 2 is a schematic sectional view showing a conventional mechanical seal. 1 ... Rotating housing of machine, 2 ... Fixed housing of machine, 3 ... Rotating shaft, 5 ... Mating ring,
6 ... Seal ring, 6a ... Inner diameter part, 10 ... Radiating ring, A ... Sliding surface.

Claims (1)

[Scope of utility model registration request] 1. A mechanical seal in which a seal ring fixed to a fixed housing of a machine body is slidably contacted with a mating ring fixed to a rotary housing, and one end of the mating ring has an inner diameter portion of the mating ring. A mechanical seal comprising a heat radiating ring which reaches the inside of the sliding surface with the ring and which has a higher thermal conductivity than the seal ring.