JPS6256391B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sealing device for equipment that uses a refrigerant.

Conventionally, a large number of sealing devices have been used in various systems such as equipment that uses refrigerants, such as various air conditioning devices and refrigerators. Rubber O-rings or packings are used, and the material of these O-rings depends on the type of refrigerant and lubricant used in each system,
Selection is made taking into consideration the combination of ambient temperature, etc. For example, special fluoro rubber materials such as Freon R-22 (CHClF ₂ ) are used for high-temperature environments, and neoprene rubbers are used for low-temperature environments. However, in recent years, compressors, etc. have become more efficient,
In order to save resources, the refrigerant atmosphere conditions in which various rubber members are placed have become more severe due to changes in Freon gas, increases in ambient temperature, and pressure fluctuations within the system. Additionally, the refrigerant is a highly permeable gas and easily permeates into the rubber material, causing deterioration of the rubber material. For example, the deterioration phenomena of rubber materials immersed in refrigerant liquid include hardening, shrinkage, swelling, foaming, and cracking, which can fatally destroy the sealing function. The reality is that there is no rubber material that has all of the above-mentioned four resistances: oil resistance, refrigerant resistance, and sealing resistance, and the rubber material is used by compromising on any of the above. The present inventor has investigated the mechanism of foaming and cracking, which is particularly important among the four resistances mentioned above. As a result, we found that the main cause of foaming and cracking in rubber materials caused by refrigerants is when pressure fluctuations in the rubber atmosphere combine rapidly with deterioration phenomena represented by swelling or contraction of rubber materials due to refrigerants and lubricating oils. .

In view of the above points, the present invention prevents pressure fluctuations in the refrigerant atmosphere to the rubber material in a sealing device in equipment using refrigerant, etc., prevents foaming and cracking of the rubber material, and also The present invention provides a sealing device that allows the use of heat-resistant rubber materials.
The gist is that in refrigerant sealing devices for equipment that use refrigerants, the front surface of the rubber O-ring or packing on the refrigerant side is made of rubber or synthetic resin O-ring or packing, or Teflon, which has excellent oil and refrigerant resistance. The gasket is installed in combination with the rubber O-ring or packing.

The present invention will be explained in detail based on illustrated embodiments.

FIG. 1 shows a first embodiment of the present invention, in which 1 is a mechanical seal used in compressors of equipment that uses refrigerant, and a fixed side sliding body 3 fixed to a housing 2 and a , refrigerant and lubricating oil (hereinafter referred to as refrigerant, etc.) sealed in the outer periphery a of the mechanical seal 1 by sliding contact of the rotating side sliding body 5 that is crimped onto the rotating shaft 4 and rotates together with the rotating shaft 4. The fixed side sliding body 3 has an O-ring 6 in the center along the inner peripheral surface of the housing 2, and a synthetic resin packing 7 on the front surface on the refrigerant side to cover the pressure receiving surface. O-ring 6
The rotary side sliding body 5 has an O-ring 8 in the center of the surface to which the rotary shaft 4 is attached, and a synthetic resin packing 9 on the front surface on the refrigerant side. The O-ring is installed in 8 directions.

In the mechanical seal 1 having the above configuration, as the pressure of the refrigerant sealed in the outer periphery a of the mechanical seal increases, the packing 7,
9 separates from the housing 2 and rotating shaft 4, and the gaps between the O-rings 6, 8 and the packings 7, 9 are filled with refrigerant, resulting in a high pressure state. Later, if the pressure on the refrigerant side suddenly drops due to a stoppage of operation or a sudden change in the refrigerant ambient temperature, the packings 7, 9 will move their pressure-receiving surfaces to the high-pressure side between the O-rings 6, 8 and the packings 7, 9. Since the lip is oriented toward the housing 2 and the rotating shaft 4 side, a sudden drop in pressure is prevented. Therefore, since the O-rings 6 and 8 made of rubber material are prevented from encountering sudden pressure fluctuations, their refrigerant resistance is significantly improved, and it is also possible to use heat-resistant rubber. The packings 7 and 9 are used to prevent the inflow of refrigerant and pressure fluctuations, and any material having excellent refrigerant resistance and oil resistance, such as Teflon, is sufficient and an active sealing function is not necessary.

FIG. 2 shows a second embodiment of the present invention, and the same reference numerals indicate the same members in the drawings. A U-shaped packing 1 made of synthetic resin is provided on the front surface of the fixed side sliding body 3 on the refrigerant side of the surface that is in contact with the housing 2.
0 is installed with the concave portion facing the housing 2 and its lip slanting toward the refrigerant side. Further, an O-ring 8 is mounted on the rotating side sliding body 5 at the center of the surface to which the rotating shaft 4 is attached, and a synthetic resin packing 11 is mounted on the front surface on the refrigerant side with the pressure-receiving surface facing the refrigerant side.

In the mechanical seal 1 having the above configuration, even when the pressure of the refrigerant increases, the packing 1
The lip of 0 is inclined toward the refrigerant side, and the lip of packing 1
1 also has its pressure-receiving surface facing the refrigerant side, so that the refrigerant etc. does not suddenly flow into the gaps between the O-rings 6, 8 and the packings 10, 11. Therefore,
Packing for immersion in refrigerant, etc. and sudden changes in refrigerant atmosphere pressure, which are the main causes of foaming of rubber materials10,11
This makes it possible to prevent these effects on the O-rings 6 and 8.

FIG. 3 shows a third embodiment of the present invention, in which a U-shaped packing 12 made of synthetic resin is formed in a recess on the front surface of the fixed side sliding body 3 on the refrigerant side of the surface circumferentially contacting the housing 2 of the mechanical seal 1. It is installed with one pressure-receiving surface facing the refrigerant side. Furthermore, a Y-shaped packing 13 made of synthetic resin is attached to the front surface of the rotating side sliding body 5 on the refrigerant side with the pressure receiving surface facing the refrigerant side, and the lower part of the metal plate 14 is bent in the O ring 8 direction on the pressure receiving surface. The tip is inserted.

In the present embodiment having the above configuration, when the pressure of the refrigerant increases as in the second embodiment, the packing 12,
Since the pressure-receiving surface of 13 is completely in the direction of the refrigerant, the lip presses the housing 2 and the rotating shaft 4, and can prevent refrigerant etc. from flowing into the gap between the O-rings 6, 8 and the packings 12, 13. . The configuration of this embodiment is more conspicuous than the second embodiment.
The influence of different types on the rings 6 and 8 can be reduced. In addition, as shown in FIG. 4, the packing 15 of the fixed side sliding body 3 is in the state shown in FIG.
It is also conceivable that the packing 16 of the rotating sliding body 5 is installed in the state shown in FIG.

The fourth embodiment shown in FIG.
7, an O-ring 20 and a U-shaped packing 21 made of synthetic resin are isolated and sandwiched between the first sealing member 18 and the second sealing member 19 by the convex portion of the second sealing member 19, and the O-ring 20 is Second sealing member 1
A U-shaped packing 21 is installed in the center of the refrigerant 9 in a recess on the side b where the refrigerant is sealed, with the concave portion facing toward the first sealing member 18 and the lip inclined toward the refrigerant side.

The above U of the fixing sealing device 17 having the above configuration
The character packing 21 is the packing 1 of the second embodiment.
As shown in FIG. 6, an O-ring 20 is placed in the concave part of the second sealing member 19 on the atmosphere side, and a U-shaped packing 22 is placed in the concave part on the refrigerant side. Sealing members 18 and 19 are adjacent to the O-ring 20 in the direction of the sealing member 18.
This embodiment also includes the case where the device is sandwiched between the devices. In addition, the above packing 7, 10, 12, 1
5, 21, and 22 may be replaced by Teflon gaskets having a substantially rectangular cross section.

In view of the above, the present invention provides equipment that uses refrigerants, in which rubber O-rings or packings of rotary sealing devices and fixed sealing devices are provided with various types of rubber or synthetic resin packing or By installing a Teflon gasket in combination, it prevents the rubber O-ring or packing from being affected by pressure fluctuations of the refrigerant and from being immersed in the refrigerant and lubricating oil, and prevents deterioration of the rubber material, especially the sealing function. It is possible to prevent foaming, cracking, etc. that would destroy the refrigerant, and it also allows the use of heat-resistant rubber materials, such as the use of high-temperature fluoro rubber instead of the conventional refrigerant Freon R-22. In addition to providing equipment, it also expands the selection range of rubber materials that have traditionally been selected at the expense of heat resistance, oil resistance, refrigerant resistance, or sealing resistance in sealing devices for various compressors. Therefore, the present invention provides a sealing device with extremely high practical effects.

[Brief explanation of the drawing]

The drawings show embodiments of the invention,
1 to 4 are half-cut sectional views of an embodiment of a mechanical seal, and FIGS. 5 and 6 are half-cut sectional views of an embodiment of a fixing sealing device. 1... Mechanical seal, 2... Housing,
3... Fixed side sliding body, 4... Rotating shaft, 5... Rotating side sliding body, 6, 8, 20... Rubber O-ring,
7, 9, 10, 11, 12, 13, 15, 16,
21, 22... Packing, 17... Fixed sealing device, 18... First sealing member, 19... Second sealing member, a, b... Sealing location for refrigerant and lubricating oil.

Claims (1)

[Claims] 1. In a refrigerant sealing device for equipment that uses refrigerant, a rubber or synthetic resin packing or Teflon gasket with excellent oil and refrigerant resistance is attached to the front surface of the rubber O-ring or packing on the refrigerant side. A sealing device characterized by having a structure that is installed in combination with the rubber O-ring or packing.