JP2010138986A - Shaft sealing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shaft sealing device that is high in reliability and merchantability. <P>SOLUTION: The shaft sealing device includes: an outer case 4 provided so as to cover the shaft circumference of a rotary shaft 2; a synthetic-rubber made lip (a main lip 8) adjacent to the inner peripheral face of the outer case 4 and brought into sliding contact with the rotary shaft in a contact state. A resin coating 8a is applied on the surface of the main lip 8, thereby reducing a friction coefficient between the main lip 8 and the rotary shaft 2. Therefore, the main lip 8 is prevented from being excessively stuck or fixed to the rotary shaft 2 so as to allow the main lip to slide on the surface of the rotary shaft 2 while maintaining the capacity. Thus, wear of the main lip 8 or the rotary shaft 2 hardly occurs. Consequently, reliability is improved, and power required by the shaft seal device is reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a shaft seal device that seals a rotary shaft portion of a machine body used in a compressor for automobile air conditioning.

  Conventionally, this type of shaft seal device uses a rubber lip (see, for example, Patent Document 1).

4 and 5 show a conventional shaft seal device described in Patent Document 1, FIG. 4 is a sectional view of the shaft seal device, and FIG. 5 is an assembly drawing. As shown in FIGS. 4 and 5, an outer case 31 provided so as to cover the shaft periphery of the rotating shaft 32, is adjacent to the inner peripheral surface of the outer case and is slidably contacted with the rotating shaft 32 and compressed. Fluoro-resin lip 33 for reducing pressure, rubber lip 34 as a main seal, fluoro-resin lip 35 for preventing entry of foreign matter from the atmosphere side, and backup ring for suppressing deformation of lips 33, 34, 35 It is composed of
Japanese Patent Laid-Open No. 9-32931

  However, when the above-described conventional configuration is operated when the pressure in the compressor is high or the temperature is high, the surface pressure of each of the lips 33, 34, and 35, which are the seal portions, rises, and each lip rotates on the rotating shaft. The sliding portions 33a, 34a, and 35a that slide with 32 have worn out at an early stage and have a problem of impairing the sealing performance.

  Further, the compressor using the shaft seal device has a problem that the lip slides on the rotating shaft to increase resistance and increase required power.

  The present invention solves the above-described conventional problems, and an object thereof is to provide a shaft seal device having high reliability and commercial property.

  In order to solve the above-described conventional problems, the shaft seal device of the present invention includes an outer case provided so as to cover the shaft periphery of the rotating shaft, and is adjacent to the inner peripheral surface of the outer case and in contact with the rotating shaft. A shaft seal device having a synthetic rubber lip to be slidably contacted, and a resin film is applied to the surface of the synthetic rubber lip.

  As a result, since the resin film is formed on the surface of the lip, the coefficient of friction between the lip and the rotating shaft is reduced, and wear of the lip or the rotating shaft is less likely to occur, thereby improving the reliability.

  Moreover, with respect to the compressor using the shaft seal device, the friction coefficient between the lip and the rotating shaft is reduced, so that the resistance of the sliding portion is reduced and the required power by the lip can be reduced.

  The shaft seal device of the present invention can reduce the wear of the lip and the rotating shaft by applying a resin coating on the surface of the synthetic rubber lip.

  1st invention comprised the outer case provided so that the shaft periphery of a rotating shaft might be covered, and the synthetic rubber lip which is slidably contacted to a rotating shaft in contact with the outer case inner peripheral surface. In the shaft seal device, the resin film is formed on the surface of the lip made of synthetic rubber, and the resin film is formed on the surface of the lip, so that the coefficient of friction between the lip and the rotating shaft is reduced and is generated by friction. Wear on the lip or rotating shaft is less likely to occur.

  In addition, since the friction coefficient between the lip and the rotating shaft is reduced with respect to the compressor using the shaft seal device, the resistance of the sliding portion is reduced, so that the required power by the lip can be reduced.

  A second aspect of the invention is a shaft provided with a case provided so as to cover the shaft periphery of the rotating shaft, and a synthetic rubber lip that is slidably contacted with the rotating shaft while being adjacent to the inner peripheral surface of the case. A sealing device, in which a resin film is formed on the surface of the synthetic rubber lip, whereby a resin film is formed on the surface of the lip, so that a coefficient of friction between the lip and the rotating shaft decreases, and the lip or Wear on the rotating shaft is less likely to occur.

  Moreover, with respect to the compressor using the shaft seal device, the required power by the lip can be reduced by reducing the coefficient of friction between the lip and the rotating shaft.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a cross-sectional view of a shaft seal device according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view of a compressor using the shaft seal device.

  1 and 2, the shaft seal device 3 is slidably contacted with the rotary shaft 2 and the rotary shaft 2 that are axially supported in the front side plate 1 in the compressor so as to ensure sealing performance with the front side plate 1. is set up.

  The shaft seal device 3 includes an outer case 4 that is a housing of the shaft seal device 3, an O-ring 5 that seals the shaft seal device 3 and the front side plate 1, and a fluororesin that is in sliding contact with the rotary shaft 2 to reduce the pressure in the compressor. Liquid side lip 6, a backup ring 7 that holds the liquid side lip 6, a synthetic rubber main lip 8 that is in sliding contact with the rotating shaft 2 to prevent oil leakage, and a fluororesin that prevents entry of foreign matter from the atmosphere side The air side lip 9 and the backup ring 10 for holding the lips.

Further, a molybdenum disulfide-based resin film (coating 8a) containing molybdenum disulfide is applied to the surface of the rubber main lip 8 with a film thickness of 15 μm.
The operation and action of the shaft seal device configured as described above will be described below.

  Since the main lip 8 provided in the outer case 4 of the shaft seal device 3 is formed of a rubber material, the tightening force (tightening force) of the lip portion with respect to the drive shaft 2 is inside the machine (right side in FIG. 1). The lip portion is pushed against the drive shaft 2 and sealed. Generally, when the wear of the lip portion increases and the tightening margin becomes negative, oil leakage is likely to occur.

In the present embodiment, since the molybdenum disulfide-based coating 8a (resin film) is formed on the surface of the main lip 8, the friction coefficient between the main lip 8 and the rotating shaft 2 is reduced. By adjusting the type and film thickness of the resin to be coated, the main lip 8 made of rubber does not stick to the rotating shaft 2 excessively or adheres to it, while keeping the surface of the rotating shaft 2 sealed. Slide. For this reason, the main lip 8 or the rotating shaft 2 is hardly worn. Therefore, it is possible to prevent the occurrence of oil leakage due to wear of the main lip 8 and provide a highly reliable compressor with improved sealing performance.

  Moreover, the required power by the shaft seal device 3 can be reduced by reducing the coefficient of friction between the main lip 8 and the rotary shaft 2 with respect to the compressor using the shaft seal device 3. Thus, for example, when used in an air conditioning compressor, it is possible to provide an efficient air conditioner with low power consumption.

  In this embodiment, the surface of the main lip 8 is coated with the molybdenum disulfide-based coating 8a with a film thickness of 15 μm. However, the surface of the main lip 8 is coated with PTFE or FEP. Can achieve the same effect.

  Further, by similarly coating the surfaces of the liquid side lip 6 and the atmosphere side lip 9, it is possible to reduce wear due to friction between each lip and the rotary shaft 2.

(Embodiment 2)
FIG. 3 is a cross-sectional view of the shaft seal device according to the second embodiment of the present invention.

  In FIG. 3, a shaft seal device 11 is installed so as to be in sliding contact with the rotary shaft 2 and the rotary shaft 2 that are axially supported in the front side plate 1 in the compressor and to ensure sealing performance with the front side plate 1. Yes.

  The shaft seal device 11 in the present embodiment can be used mainly in a low-pressure type compressor in which the pressure compressed by the compressor is relatively low, and the number of lips slidingly contacting the rotating shaft 2 is two. This is different from the first embodiment. The shaft seal device 11 is bonded to a case 12 that is a housing of the shaft seal device 11, seals the shaft seal device 11 and the front side plate 1, and slidably contacts the rotary shaft 2 to seal the pressure in the compressor. The main lip 13 is made of rubber, the air-side lip 14 made of fluorine resin for preventing foreign substances from entering from the atmosphere side, and the backup ring 10 for holding the lips.

  Further, a PTFE resin film (coating 13a) containing PTFE is applied to the surface of the sliding portion of the rubber main lip 13 with a film thickness of 15 μm.

  About the shaft seal device comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  In the present embodiment, the PTFE coating 13a is formed on the surface of the main lip 13, so that the friction coefficient between the main lip 13 and the rotating shaft 2 is reduced. Therefore, the main lip 13 made of rubber does not excessively stick to or adhere to the rotating shaft 2 and slides on the surface of the rotating shaft 2 while maintaining the sealing performance. For this reason, the main lip 13 or the rotating shaft 2 is hardly worn.

  Moreover, the required power by the shaft seal device 11 can be reduced by reducing the coefficient of friction between the main lip 13 and the rotary shaft 2 with respect to the compressor using the shaft seal device 11. Therefore, oil leakage due to wear of the main lip 8 does not occur, and a highly reliable compressor can be provided.

  And in this Embodiment, since it uses for a low pressure type compressor, even if it is the structure where the main lip 13 contacts the liquid side directly, it is possible to maintain sealing performance. Therefore, the liquid side lip can be eliminated, and a highly reliable and inexpensive compressor can be provided.

  The main lip 13 is provided over the inner and outer surfaces of the case 12, and the portion located inside the case 12 functions as a sealing material that shuts off the compressor and the atmosphere side of the compressor as described above. The located part functions as a sealing material between the case 12 of the shaft seal device 11 and the front side plate 1. Therefore, by adopting the configuration of the present embodiment, the O-ring 5 for sealing between the case 12 and the front side plate 1 as shown in FIG. 1 is not necessary, and can be provided at a lower cost. It becomes.

  In the present embodiment, since the PTFE coating 13a is applied to the surface of the main lip 13 with a film thickness of 15 μm, the friction coefficient is lowered, and the main lip 13 or the rotating shaft 2 is worn. Although it is less likely to occur, the same effect can be obtained by applying a molybdenum disulfide-based or FEP-based coating.

  Furthermore, similarly, the surface of the atmosphere-side lip 14 is similarly coated with molybdenum disulfide, PTFE, or FEP, so that wear due to friction between the atmosphere-side lip 14 and the rotary shaft 2 can be reduced.

  As described above, the shaft seal device according to the present invention uses the shaft seal device because the resin coating is applied to the lip surface, so that the wear of the lip and the rotating shaft can be reduced and the reliability is improved. It can also be applied to other fields such as heater pumps, turbochargers and engines.

Sectional drawing of the shaft seal apparatus in Embodiment 1 of this invention Sectional drawing of the compressor which installed the shaft seal apparatus in Embodiment 1 Sectional drawing of the shaft seal apparatus in Embodiment 2 of this invention Sectional view of a conventional shaft seal device Assembly drawing of conventional shaft seal device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Front side plate 2 Rotating shaft 3 Shaft sealing device 4 Outer case 5 O ring 6 Liquid side lip 6a Coating 7 Backup ring 8 Main lip 8a Coating 9 Atmosphere side lip 10 Backup ring 11 Shaft sealing device 12 Case 13 Main lip 13a Coating 14 Atmosphere side lip 14a Coating 15 Backup ring

Claims (2)

A shaft seal device comprising an outer case provided so as to cover the shaft periphery of the rotating shaft, and a synthetic rubber lip that is adjacent to the inner peripheral surface of the outer case and is in sliding contact with the rotating shaft in a contact state. A shaft seal device in which a resin film is applied to the surface of the synthetic rubber lip. A shaft seal device provided with a case provided so as to cover the shaft periphery of the rotating shaft, and a synthetic rubber lip which is adjacent to the inner peripheral surface of the case and is slidably contacted with the rotating shaft in a contact state, A shaft seal device in which a resin film is applied to the surface of the synthetic rubber lip.