JPH053743U - Shaft seal device - Google Patents

Abstract

(57) [Abstract] [Purpose] The lubricity and the sealability of the sealing sliding surface S of the mechanical seal 30 can be appropriately adjusted, and the fixing and freezing of the sealing sliding surface S can be facilitated. A fixed sliding ring 31 of a mechanical seal 30 is airtightly fitted to a housing 10, and the abutting surface 10 of the housing 10 and the fixed sliding ring 31 are in axial contact with each other.
A concave portion 31b is formed in either one of a and 31a, and the concave portion 31b accommodates the electric heater 40 through which an arbitrary current is conducted from the outside.
And a heat insulating material 41 is interposed between them.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a shaft sealing device that seals the circumference of a rotary shaft of a device, and more particularly to a device that seals with a mechanical seal.

[0002]

[Prior Art]

 Conventionally, mechanical seals have been known as means for sealing the rotating shaft of equipment, but when the object to be sealed is a high-viscosity liquid, lubrication between the sealing sliding surfaces of the mechanical seal is not performed well, or the seal is sealed. The sliding surface was sometimes fixed with a high-viscosity liquid, and when the object to be sealed was a low-temperature fluid of 0 ° C or less, water vapor in the atmosphere was sometimes frozen in the mechanical seal.

Further, in the mechanical seal, heat generated by sliding causes only the sealing sliding surface to have a high temperature, which causes distortion of the sliding ring due to heat, and thus distortion of the sealing sliding surface, resulting in lubricity and sealing. The sex was sometimes unstable.

[0004]

[Problems to be solved by the device]

 The present invention has been made in view of the above circumstances, and its purpose is to properly adjust the lubricity and the sealing property of the sealing sliding surface of the mechanical seal to release the sticking and the freezing. To make it easier.

[0005]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, a shaft sealing device according to the present invention is configured such that a fixed sliding ring of a mechanical seal is airtightly fitted to a housing, and the abutting surface of the fixed sliding ring and the housing are in axial contact with each other. A concave portion is formed in either one of the above, an electric heater through which an arbitrary current is conducted from the outside is accommodated in the concave portion, and a heat insulating material is interposed between the electric heater and the housing.

[0006]

[Action]

 According to the above structure, the fixed slide ring of the mechanical seal can be arbitrarily heated from the side opposite to the sealed slide surface by the electric heater in the recess formed in the abutment surface of the housing or the fixed slide ring. The temperature of the sealing surface of the mechanical seal can be arbitrarily adjusted according to the operating conditions to properly maintain the viscosity of the liquid to be sealed existing on the sealing surface, to release the freeze, and to fix the fixed sliding ring. It is possible to correct the thermal imbalance between the sealing sliding surface side and the back surface side and reduce the distortion of the sealing sliding surface due to the sliding heat.

Further, the heat insulating material interposed between the electric heater and the housing prevents the heat of the electric heater from being absorbed by the housing, so that the fixed sliding ring can be efficiently supplied with the heat. It is a thing.

[0008]

【Example】

 FIG. 1 shows a first embodiment of a shaft sealing device according to the present invention, in which 10 is a housing, 20 is a rotary shaft inserted into a shaft hole of the housing 10, and 30 is a housing 10 and a rotary shaft 20. It is a mechanical seal installed between. The mechanical seal 30 has a non-rotating fixed slide ring 31 provided on the housing 10 side and a rotary slide ring 33 provided on the rotary shaft 20 side and axially opposed to the fixed slide ring 31. The rotary sliding ring 33 has a rotary seal structure in which a spring 37 elastically urges the rotary sliding ring 33.

A housing portion 12 is formed on the inner diameter of the flange portion 11 of the housing 10. The fixed slide ring 31 of the mechanical seal 30 is fitted in the housing portion 12, the gap of the outer peripheral surface is sealed with a gasket 32, and is restrained in a non-rotating state.

The rotary sliding ring 33 of the mechanical seal 30 is provided on the outer peripheral surface of the rotary shaft 20 so as to be movable in the axial direction via a shaft packing 34, and is integrated with the rotary shaft 20 via a collar 35 and a compression ring 36. While rotating, it is pressed against the fixed slide ring 31 by the urging force of the spring 37 supported by the collar 35 to form a sealed slide surface S.

An annular recess 31b is formed in the anti-sealing sliding surface (abutting surface) 31a of the fixed sliding ring 31 that axially opposes the end surface (abutting surface) 10a in the accommodating portion 12. The electric heater 40 is housed in the recess 31b, and the electric heater 40 and the abutting surface 10a of the housing 10 are insulated by a heat insulating material 41 sealed in the opening of the recess 31b. A lead wire 42 extending from the electric heater 40 is led out to the outside through holes 14 and 15 formed in the flange portion 11 of the housing 10, and constitutes a circuit in which a power source 43, a switch 44 and a variable resistor 45 are connected in series.

According to this embodiment, when the liquid A to be sealed is a high viscosity liquid or a low temperature liquid of 0 ° C. or less, the switch 44 is closed and the electric heater 40 is caused to generate heat as necessary. The fixed sliding ring 31 is heated from the anti-sealing sliding surface (abutting surface 31a) side. For this reason, it is possible to easily release the fixed state of the sealing sliding surface S due to the high-viscosity liquid before starting the equipment, or to easily release the state where the moisture in the atmosphere freezes near the sealing sliding surface S due to the low temperature. it can.

Since the amount of heat generated by the electric heater 40 can be arbitrarily adjusted by controlling the current with the variable resistor 45, the temperature of the sealing sliding surface S can be appropriately adjusted according to individual use conditions. It is possible to control and obtain a good lubrication state, reduce the strain of the fixed sliding ring 31 due to the temperature difference between the sealing sliding surface S side that generates sliding heat and the abutting surface 31a side, and seal the sliding surface. It is possible to prevent an increase in leakage from the moving surface S.

Since the heat escape from the electric heater 40 to the housing 10 is blocked by the heat insulating material 41, the capacity of the heater can be reduced, and the increase in power consumption and the increase in size of the apparatus can be suppressed.

FIG. 2 shows a second embodiment of the present invention. Instead of the recess 31b of the fixed sliding ring 31 shown in FIG. 1, an annular ring is formed on the abutment surface 10a in the housing portion 12 of the housing 10. A recess 10b is formed, and the electric heater 40 is housed in the recess 10b via a heat insulating material 41 having a U-shaped cross section. Other configurations are the same as those in FIG.

According to the present embodiment, since the recess 10b can be easily processed in the housing 10 made of steel, for example, the fixed sliding ring 31 has a small size and a small diameter, and a hard or brittle material such as ceramic or cemented carbide. It is particularly useful when it is difficult to form the concave portion 31b in the fixed sliding ring 31, and has substantially the same effect as the previous embodiment shown in FIG.

[0017]

[Effect of the device]

 As described above, according to the present invention, the electric heater heats the fixed sliding ring of the mechanical seal from its anti-sealing sliding surface side with an arbitrary amount of heat, and the mechanical seal is sealed and slid by the high viscosity or low temperature liquid to be sealed. It is possible to easily fix the surface and release the freezing, and alleviate the distortion due to the thermal imbalance between the sealing sliding surface side and the anti-sealing sliding surface side of the fixed sliding ring, thus ensuring proper lubricity and sealing performance. Can be controlled.

[Brief description of drawings]

FIG. 1 is a schematic configuration explanatory view showing a first embodiment of the present invention.

FIG. 2 is a schematic structural explanatory view showing a second embodiment of the present invention.

[Explanation of symbols]

 10 Housings 10a, 31a Abutment surfaces 10b, 31b Recesses 12 Receiving part 20 Rotating shaft 30 Mechanical seal 31 Fixed sliding ring 33 Rotating sliding ring 40 Electric heater 41 Heat insulating material 45 Variable resistor

Claims (1)

[Claims for utility model registration] [Claim 1] A fixed sliding ring of a mechanical seal is airtightly fitted to a housing, and the fixed sliding ring and the housing abutting surface are in axial contact with each other. A shaft sealing device characterized in that a recess is formed in either one of the recesses, an electric heater through which an arbitrary current is conducted from the outside is accommodated, and a heat insulating material is interposed between the electric heater and the housing. .