JPH0741932U - Gas seal switch shaft seal device - Google Patents

Abstract

(57) [Summary] [Structure] Fixed in a container filled with arc-extinguishing gas in a shaft seal device for a drive shaft that drives a movable contactor that is brought into contact with and separated from a fixed contactor by operating a handle, provided in a gas charging switch The bearing housing, the drive shaft supported through the bearing provided in the bearing housing, the seal material provided between the inner peripheral surface of the bearing housing and the outer peripheral surface of the drive shaft with a space, and the seal material. Between the inner peripheral surface of the bearing housing and the outer peripheral surface of the drive shaft, a filling means for pressing the liquid and the liquid to press the liquid to the sealing surface is provided. [Effect] Since the liquid is filled between the outer peripheral surface of the drive shaft and the inner peripheral surface of the bearing housing, the arc-extinguishing gas sealed in the container is not affected even when the ambient temperature decreases and the rubber elastic force decreases. Never leak outside.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This proposal relates to a shaft sealing device for a drive shaft of a gas filled switch used in a low temperature atmosphere.

[0002]

[Prior art]

 As shown in FIG. 3, the shaft sealing device for the drive shaft, which drives the movable contactor that comes into contact with and separates from the fixed contactor provided in the gas-filled switch by operating the handle, is mounted on the bearing housing 16 fixed to the case 15. Two bearings 17, 17 are provided side by side in this direction, and a drive shaft 18 is attached to this bearing. Grooves 19, 19 are provided on the outer circumference of the drive shaft between the bearings, and O-rings 20, 20 are fitted in the grooves to seal the inner peripheral surface of the bearing housing and the groove surface of the drive shaft, and The arc-extinguishing gas filled in the unit is configured so as not to leak outside the device. A handle 21 is provided at one end of the drive shaft, and a movable contactor (not shown) is attached to the other end. For O-rings, the shaft sealing device becomes compatible with the sealing surface over time due to the compression deformation and reaction force of the O-ring, and there is almost no leakage from the interface, and the appropriate sealing surface roughness, compression rate, and rubber hardness are obtained. The leakage from the interface can be almost ignored by selecting the above, and the gas leakage is mainly permeation leakage that penetrates through the rubber, so a highly reliable shaft sealing device can be obtained relatively easily.

[0003]

[Problems to be solved by the device]

 In the conventional type, when the atmospheric temperature decreases, the rubber elastic force decreases, and the outer peripheral surface of the drive shaft and the O-ring or the inner peripheral surface of the bearing housing become incompatible with the O-ring, preventing leakage from the interface. There was a problem that I could not do it. Therefore, an object of the present invention is to provide a shaft seal device for a gas-filled switch which does not leak gas from the interface even in a low temperature region.

[0004]

[Means for Solving the Problems]

 The first invention is a shaft sealing device for a drive shaft, which is provided in a gas charging switch and drives a movable contact which comes into contact with and separates from a fixed contact by a hand operation. The housing, the drive shaft supported via the bearing provided in the bearing housing, the seal material provided side by side with an interval between the inner peripheral surface of the bearing housing and the outer peripheral surface of the drive shaft, and the bearing between the seal materials. A storage tank provided between the inner peripheral surface of the housing and the outer peripheral surface of the drive shaft, a liquid filled in the storage tank, and a pressing means for pressing the liquid to pump the liquid to the sealing surface are provided. . A second invention is mounted between a taper portion provided on the outer periphery of the drive shaft and the inner periphery of the bearing housing in the reservoir, the liquid filled in the reservoir, and the bearing housing and the protrusion of the drive shaft. A spring is provided. A third invention is to provide a communication hole provided in the bearing housing for communicating a high-pressure arc-extinguishing gas with the liquid filled in the storage tank between the bearing housing and the drive shaft.

[0005]

[Action]

 Therefore, since a storage tank is provided between the outer peripheral surface of the drive shaft and the inner peripheral surface of the bearing housing, the storage tank is filled with liquid, and the liquid is pumped to the sealing surface by the spring force or the gas pressure enclosed in the container. The arc-extinguishing gas enclosed in the container does not leak out of the device even if the ambient temperature decreases and the rubber elasticity decreases.

[0006]

【Example】

The present invention will be described with reference to the embodiment shown in FIGS. FIG. 1 is a schematic view showing an axial cross section of a shaft sealing device of the present invention, and FIG. 2 is a schematic view showing an axial cross section of a shaft sealing device of another embodiment. Reference numeral 1 is a switch container in which an arc-extinguishing gas is sealed, 2 is a bearing housing composed of a tubular body 3 and a flange 4 provided at an end of the tubular body, and the tubular body is opened from the opening of the vessel. It is inserted into the container, and the flange is fixed to the container wall of the container via a sealing material 5 with a bolt (not shown). Reference numeral 6 denotes a drive shaft supported by the bearing housing 3 via the bearings 7, 7, and has a handle (not shown) fixed to one end of the drive shaft and a movable contactor (not shown) at the other end. It is configured to be attached and detached from the fixed contact. Annular projections 8 and 8 and annular projections 9 and 9 are provided at intervals on the outer circumference of the drive shaft between the bearings 7 and 7. Sealing materials 10, 11 such as O-rings are mounted between the annular projections 8, 8 and 9, 9 to seal the circumferential surface of the bearing housing and the outer peripheral surface of the drive shaft. Reference numeral 12 denotes a storage tank formed between the seal members 10 and 11 and between the circumferential surface of the bearing housing and the outer peripheral surface of the drive shaft. The storage tank is filled with liquid. Reference numeral 14 is a spring stretched between the end surface of the bearing 7 and the end surface of the annular projection so as to press the drive shaft in the direction of arrow A. In the shaft seal device of the gas-filled switch thus configured, the rubber is not familiar to the seal surface of the drive shaft 6 in the low temperature region where the elasticity of the seal materials 10 and 11 is low, and this seal does not occur over time. At the interface of the surfaces, the liquid that is filled in the reservoir by pressing the drive shaft in the direction of arrow A by the spring 13 is on the sealing surface, and this liquid seals the leakage of gas in the sealed container. Liquid is more viscous than gas and less likely to leak from the seal interface, but even if a slight liquid leak occurs, or if the liquid expands or contracts due to temperature fluctuations, the drive shaft via a spring By sliding 1, the hydraulic pressure is always constant and stable sealing performance can be obtained. JISB2401 P30; 2104-70 (ethylene propylene rubber) O-ring manufactured by Mitsubishi Cable Industries, Ltd. is used as a sealing material, and the sealing conditions are a surface roughness of 1.5 S, a compression rate of 15%, and a sealed gas pressure of 5 kg / cm ^2. As a result of performing a leak test at low temperature using FOMBLIN Z03 manufactured by Montecatini Co. on the liquid (g), the leak rate after driving at −70 ° C. was 1 × 10 ^{−5 which} is the detection limit of the device. It was cc / sec or less. Further, the leak rate when the liquid 5 was not enclosed was 50 cc / sec or more. The reference numeral 15 designates a communication hole provided in the bearing housing, which communicates with the gas filled in the gas container and the liquid, so that the gas pressure of the extinguishing gas in the gas container is applied to the liquid.

[0007]

[Effect of device]

 As described above, the present invention is provided with means for applying a pumping force to the liquid filled in the storage tank between the seal material mounted axially between the inner peripheral surface of the bearing housing and the outer peripheral surface of the drive shaft. Even in the low temperature region where the rubber seal alone cannot drive the gas seal of the drive shaft due to the rubber elasticity decreasing or disappearing, the gas seal can be reliably provided with a relatively simple structure.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part of a shaft sealing device for a gas filled switch according to the present invention.

FIG. 2 is a sectional view of an essential part of a gas filled switch according to an embodiment of the present invention.

FIG. 3 is a sectional view of a main part of a conventional shaft sealing device for a gas filled switch.

[Explanation of symbols]

 1 Container 2 Bearing Housing 6 Drive Shaft 7 Bearings 8 and 9 Annular Protrusions 10 and 11 Sealing Material 12 Storage Tank 13 Liquid 14 Spring 15 Communication Hole

Claims (3)

[Scope of utility model registration request] 1. A shaft-sealing device for a drive shaft, wherein a movable contactor provided in a gas charging switch is connected to and separated from a fixed contactor by a handle operation, and a bearing housing fixed to a container filled with arc-extinguishing gas. A drive shaft supported via a bearing provided in the bearing housing, a seal material provided between the inner peripheral surface of the bearing housing and the outer peripheral surface of the drive shaft with a space therebetween, and the seal material between the seal material and the bearing housing. It is characterized in that a storage tank provided between the inner peripheral surface and the outer peripheral surface of the drive shaft, a liquid filled in the storage tank, and a pressing means for pressing the liquid to pump the liquid to the sealing surface are provided. A shaft seal device for a gas filled switch. 2. A taper portion provided on the outer circumference of the drive shaft in the storage tank and the inner circumference of the bearing housing, the liquid filled in the storage tank including the taper portion, and the protrusion between the bearing housing and the drive shaft. The shaft sealing device for a gas filled switch according to claim 1, further comprising a spring mounted on the shaft. 3. The shaft sealing device for a gas charging switch according to claim 1, further comprising a communication hole provided in the bearing housing, the communication hole communicating with a liquid filled in a reservoir between the bearing housing and the drive shaft.