CA2152454C - Scroll compressor - Google Patents

Scroll compressor

Info

Publication number
CA2152454C
CA2152454C CA002152454A CA2152454A CA2152454C CA 2152454 C CA2152454 C CA 2152454C CA 002152454 A CA002152454 A CA 002152454A CA 2152454 A CA2152454 A CA 2152454A CA 2152454 C CA2152454 C CA 2152454C
Authority
CA
Canada
Prior art keywords
scroll
end plate
swivel
thrust
swivel scroll
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
CA002152454A
Other languages
French (fr)
Other versions
CA2152454A1 (en
Inventor
Takayuki Iio
Shigeki Miura
Ryuhei Tanigaki
Mikihiko Ishii
Makoto Takeuchi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Heavy Industries Ltd
Original Assignee
Mitsubishi Heavy Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Heavy Industries Ltd filed Critical Mitsubishi Heavy Industries Ltd
Publication of CA2152454A1 publication Critical patent/CA2152454A1/en
Application granted granted Critical
Publication of CA2152454C publication Critical patent/CA2152454C/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04CROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C18/00Rotary-piston pumps specially adapted for elastic fluids
    • F04C18/02Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents
    • F04C18/0207Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents both members having co-operating elements in spiral form
    • F04C18/0215Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents both members having co-operating elements in spiral form where only one member is moving
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04CROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C18/00Rotary-piston pumps specially adapted for elastic fluids
    • F04C18/02Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04CROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2230/00Manufacture
    • F04C2230/90Improving properties of machine parts
    • F04C2230/91Coating
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05BINDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
    • F05B2230/00Manufacture
    • F05B2230/90Coating; Surface treatment
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05CINDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
    • F05C2225/00Synthetic polymers, e.g. plastics; Rubber
    • F05C2225/04PTFE [PolyTetraFluorEthylene]

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Rotary Pumps (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)

Abstract

Unusual wearing and seizure on an outer surface 15a of an end plate 15 of a swivel scroll 14 and on a sliding surface 36a of a thrust slide bearing 36 which may occur at the time of re-starting of a compressor after a long time cessation are avoided.
Any one, or both, of the outer surface 15a of the end plate 15 of the swivel scroll 14 and the sliding surface 36a of the thrust slide bearing 36 contacting slidably thereto is/are applied to by a coating membrane 40 of a solid lubricating material.

Description

2152~

SCROLL COMPRESSOR

BACKGROUND OF THE INVENTION:
Field of the Invention:
The present invention relates to a scroll type compressor.
Description of the Prior Art:
One example of a conventional scroll compressor is shown in Fig. 3. In Fig. 3, a hermetic housing, being designated by numeral 1, consists of a cup-like body 2, a front end plate 4 fixed thereto by bolts 3 and a cylindrical element 6 fixed thereto by bolts 5. A rotating shaft 7, passing through said cylindrical element 6, is supported rotatably by bearings 8 and 9 in the hermetic housing 1.
A stationary scroll 10 and a swivel scroll 14 are built-in in the hermetic housing 1. Said stationary scroll 10 has an end plate 11 and a spiral wrap 12 provided standingly on its inner surface, said end plate 11 being tied to the cup-like body 2 by bolts 13 and the stationary scroll 10 being thereby fixed in the housing 1. The outer circumferential surface of the end plate 11 and the inner circumferential surface of the cup-like body 2 being sealingly contacted each other, thereby the inner space of the housing 1 being partitioned, a discharge cavity 31 is formed on the outer side of the end plate 11 and a suction 21524~

cell 28 is defined on the inner side of the end plate 11.
At the central part of the end plate 11, a discharge port 29 is digged so that opening and closing of the discharge port 29 is made by a discharge valve 30.
The swivel scroll 14 has an end plate 15 and a spiral wrap 16 provided standingly on its inner surface, said spiral wrap 16 being of substantially same dimensions and shape as the spiral wrap 12 of the stationary scroll 10.
The swivel scroll 14 and the stationary scroll 10 are provided each other eccentrically by a length of a radius of the revolution and engaged each other with a deviation of angle of 180 degrees, as shown in the figure.
Thus, a tip seal 17 provided burriedly on the top surface of the spiral wrap 12 being sealingly contacted to the inner surface of the end plate 15, and a tip seal 18 provided burriedly on the top surface of the spiral wrap 16 being sealingly contacted to the inner surface of the end plate 11, the side surfaces of spiral wraps 12 and 16 make line contacts each other at a plurality of places, thereby a plurality of compression chambers l9a and l9b, being nearly in a point symmetry each other around the centers of the spirals, are formed and a cell 22 is formed at the central part of the spirals.
Within a cylindrical boss 20 provided projectingly at the central part of the outer surface of the end plate - 2152~4 15, a drive bush 21 is insertedly provided and is rotatable on a revolutional bearing 23, and within a slide hole 24 digged in said drive bush 21, an eccentric drive pin 25, projecting from the inner end of the rotating shaft 7, is provided slidably. Said drive bush 21 is fitted with a balance weight 27 for balancing dynamic unbalances caused by revolutional swivel motions of the swivel scroll.
Numeral 26 designates a rotation preventing mechanism consisting of an Oldham link for allowing revolutional swivel motions of the swivel scroll 14 but preventing a rotation thereof, numeral 36 designates a thrust slide bearing and numeral 37 designates a balance weight fixed to the rotating shaft 7.
With rotation of the rotating shaft 7, the swivel scroll 14 is driven via swivel drive mechanism consisting of the eccentric drive pin 25, drive bush 21, boss 20, etc. and the swivel scroll 14, being prevented from rotating by the rotation preventing mechanism 26, does revolutional swivel motions on a circular track having a radius of the revolution, i.e. a radius being the eccentricity amount between the rotating shaft 7 and the eccentric drive pin 25.
Then, the line contact parts of the side surfaces of the spiral wraps 12 and 16 move gradually to the direction of the spiral centers. Accompanying therewith, a gas flown into the suction chamber 28 through a suction - 21524~4 inlet (not shown in the figures) is taken into each of the compression chambers l9a and l9b from openings of the outer finish ends of the spiral wraps 12 and 16. While being compressed, the gas comes in the central cell 22 and, passing through the discharge port 29 and opening the discharge valve 30, it is discharged into the discharge cavity 31 and flown out through a discharge outlet (not shown in the figures).
By the compressed gas in the compression chambers l9a and l9b, a thrust load works on the swivel scroll 14.
Said thrust load is supported by a thrust surface 4a formed on an inner end surface of a front end plate 4 via a thrust slide bearing 36 contacting slidably to an outer circumferential edge of an outer surface 15a of the end plate 15 of the swivel scroll 14.
Said thrust slide bearing 36, being made of a thin plate of steel like SK material (carbon tool steel), etc., is provided on the inner end surface of the front end plate 4 with a measure of preventing round motions so that the thrust slide bearing does not revolve together with the swivel scroll 14 even when the swivel scroll 14 is making revolutional swivel motions.
In said conventional scroll compressors, the outer surface 15a of the end plate 15 of the swivel scroll 14 and the sliding surface of the thrust slide bearing 36 2152~4 contacting slidably thereto are lubricated by mists of lubricating oil contained in the gas refrigerant sucked into the suction chamber 28.
However, if the compressor is operated for long hours, the refrigerant remains stagnantly in the hermetic housing 1 and dilutes the lubricating oil gradually, thereby such a case where the operation at the time of starting is done with the thrust slide bearing 36 being least lubricated, i.e. a dry operation, may happen.
Further, after the start of the compressor, it takes some time (for example, some tens of seconds) until the sliding surface of the thrust slide bearing 36 comes to be lubricated by mists of lubricating oil contained in the sucked gas refrigerant, and there is a fear of such an accident as seizure on the thrust slide bearing 36 occurring due to a dry operation and reliability of the compressor being harmed.

SUMMARY OF THE INVENTION:
It is therefore an object of the present invention to dissolve the above-mentioned shortcomings in the prior art, and a first invention relates to a scroll compressor in which a swivel scroll engaged with a stationary scroll fixed in a hermetic housing makes revolutionary swivel motions while it is prevented from rotating, and a thrust load -2152~

working on said swivel scroll is supported by a thrust receiving surface of said hermetic housing via a thrust slide bearing contacting slidably to an outer surface of an end plate of said swivel scroll, wherein at least one of said outer surface of the end plate of the swivel scroll and the sliding surface of said thrust slide bearing contacting slidably thereto is applied to by a coating membrane made of a solid lubricating material.
A second invention relates to a scroll compressor in which a swivel scroll engaged with a stationary scroll fixed in a hermetic housing makes revolutionary swivel motions while it is prevented from rotating, and a thrust load working on said swivel scroll is supported by a thrust receiving surface of said hermetic housing via a thrust slide bearing contacting slidably to an outer surface of an end plate of said swivel scroll, wherein at least one of said outer surface of the end plate of the swivel scroll and said thrust receiving surface is applied to by a coating membrane made of a solid lubricating material.
As for said solid lubricating material, a solid lubricating material made on the basis of 4-fluoroethylene resin can be used.
In the first invention, as the coating membrane of a solid lubricating material has an excellent anti-wearing and lubricating ability even under a condition where 21524~4 lubricating oil is not well supplied, unusual wearing of the sliding surfaces of the outer surface of the swivel scroll end plate and of the thrust slide bearing provided slidably thereon can be avoided even in a case where a dry operation or the like occurs at the time of re-starting of the compressor after a long time cessation.
In the second invention, unusual wearing and seizure of the outer surface of the swivel scroll end plate and of the thrust receiving surface contacting slidably thereto at the time of re-starting of the compressor after a long time cessation can be avoided.

BRIEF DESCRIPTION OF THE DRAWINGS:
In the accompanying drawings:
Fig. 1 shows a first preferred embodiment of the present invention, wherein Fig. (A) is a longitudinal cross section of a scroll compressor, Fig. (B) is a front view of a thrust slide bearing, Fig. (C) is a cross section taken on line C-C of Fig. (B). Fig. (D) is a partly enlarged cross section showing an example of modification and Fig. (E) is a partly enlarged cross section showing another example of modification.
Fig. 2 shows a second preferred embodiment of the present invention, wherein Fig. (A) is a longitudinal cross section of a scroll compressor, Fig. (B) is a partly 21S2~4 enlarged cross section, Fig. (C) is a partly enlarged cross section of an example of modification and Fig. (D) is a partly enlarged cross section of another example of modification.
Fig. 3 is a longitudinal cross section of a conventional scroll compressor.

DESCRIPTION OF THE PREFERRED EMBODIMENTS:
A first preferred embodiment of the present invention is shown in Fig. 1. As shown Fig. l(A), (B) and (C), the sliding surface 36a of the thrust slide bearing 36 is applied to by a coating membrane 40 made of a solid lubricating material based on PTFE resin (4-fluoroethylene resin, a trade name: TEFLON) being coated and burnt.
Further, as shown in Fig. l(D), the outer surface 15a of the end plate 15 of the swivel scroll 14 can be applied to by a like coating membrane 40, and as shown in Fig. l(E), both the slide surface of the thrust slide bearing 36 and the outer surface 15a of the end plate 15 of the swivel scroll 14 can be applied to by a like coating membrane.
As said coating membrane 40 has an excellent anti-wearing and lubricating ability even under a condition where lubricating oil is not well supplied and lubricating oil film is not well formed, unusual wearing and seizure of the ~ 2152454 .

sliding surface 36a and the outer surface 15a can be avoided even when a dry operatlon or the like may happen for a some while (for example, some tens of seconds) at the time of re-starting of the compressor after a long time cessation.
Further, as for a solid lubricating material, such of a solid lubricating material of a base material other than PTFE can be used, if such is excellent in anti-wearing and lubricating ability.
Other constructions and functions being same as those of conventional ones as shown in Fig. 3, corresponding elements are designated by same numerals.
A second preferred embodiment of the present invention is shown in Fig. 2.
In this second preferred embodiment, as shown in Fig. 2(A), the inner end surface of the front end plate 4, i.e. the thrust receiving surface 4a slides directly on the outer surface 15a of the end plate 15 of the swivel scroll 14. And, as shown in Fig. 2(B), the sliding surface 36a of the thrust slide bearing 36 is applied to by a coating membrane 40 made of a solid lubricating material based on PTFE resin (4-fluoroethylene resin, a trade name: TEFLON) being coated and burnt.
Further, the outer surface 15a of the end plate 15 of the swivel scroll 14, as shown in Fig. 2(C), or both the thrust receiving surface 4a and the outer surface 15a of the 21~ 2 4 5 4 end plate 15 of the swivel scroll 14, as shown in Fig. 2(D), can be applied to by a coating membrane 40.
As this coating membrane 40 has an excellent anti-wearing and lubricating ability even under a condition where lubricating oil is not well supplied and a lubricating oil film is not well formed, a lubrication insufficiency on the sliding surfaces of the outer surface 15a of the end plate 15 and the thrust receiving surface 4a does not occur even in a dry operation or the like, and unusual wearing and seizure of these surfaces can be avoided.
Further, both the front end plate 4 and the swivel scroll 14 being able to be made of an aluminium material and the thrust receiving surface 4a of the front end plate 4 and the outer surface 15a of the end plate 15 of the swivel scroll 14 being able to be slidably contacted each other, a good effect on a weight reduction of the compressor and on a cost reduction thereof can be obtained.
In the first invention, as any one or both of the outer surface of the end plate of the swivel scroll and the sliding surface of the thrust slide bearing is/are applied to by a coating membrane made of a solid lubricating material, unusual wearing and seizure of the outer surface of the end plate of the swivel scroll and the sliding surface of the thrust slide bearing can be avoided even at the time of re-starting of the compressor after a long time -cessation, and reliability of the compressor can be increased.
In the second invention, as any one or both of the outer surface of the end plate of the scroll and the thrust receiving surface is/are applied to by a coating membrane, unusual wearing and seizure of the outer surface of the end plate of the swivel scroll and the thrust receiving surface can be avoided, likewise as in the first invention, at the time of re-starting of the compressor after a long time cessation, and both the swivel sc~oll and the hermetic housing being able to be made of aluminium and the thrust slide bearing being able to be omitted, a weight reduction of the compressor and a cost reduction thereof becomes possible.
While the preferred form of the present invention has been described, variations thereto will occur to those skilled in the art within the scope of the present inventive concepts which are delineated by the following claims.

Claims (3)

1. A scroll compressor in which a swivel scroll (14) engaged with a stationary scroll (10) fixed in a hermetic housing (1) makes revolutionary swivel motions while it is prevented from rotating, and a thrust load working on said swivel scroll (14) is supported by a thrust receiving surface (4a) of said hermetic housing (1) via a thrust slide bearing (36) contacting slidably to an outer surface (15a) of an end plate (15) of said swivel scroll (14), characterized in that at least one of said outer surface (15a) of the end plate (15) of the swivel scroll (14) and the sliding surface (36a) of said thrust slide bearing (36) contacting slidably thereto is applied to by a coating membrane (40) made of a solid lubricating material.
2. A scroll compressor in which a swivel scroll (14) engaged with a stationary scroll (10) fixed in a hermetic housing (1) makes revolutionary swivel motions while it is prevented from rotating, and a thrust load working on said swivel scroll (14) is supported by a thrust receiving surface (4a) of said hermetic housing (1) via a thrust slide bearing (36) contacting slidably to an outer surface (15a) of an end plate (15) of said swivel scroll (14), characterized in that at least one of said outer surface (15a) of the end plate (15) of the swivel scroll (14) and said thrust receiving surface (4a) is applied to by a coating membrane (40) made of a solid lubricating material.
3. A scroll compressor as claimed in Claim 1 or in Claim 2, characterized in that a solid lubricating material (40) made on the basis of 4-fluoroehtylene resin, as said solid lubricating material, is used.
CA002152454A 1994-08-19 1995-06-22 Scroll compressor Expired - Lifetime CA2152454C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP21782494A JP3364016B2 (en) 1994-08-19 1994-08-19 Scroll compressor for refrigerator
JP6-217824 1994-08-19

Publications (2)

Publication Number Publication Date
CA2152454A1 CA2152454A1 (en) 1996-02-20
CA2152454C true CA2152454C (en) 1998-11-17

Family

ID=16710325

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002152454A Expired - Lifetime CA2152454C (en) 1994-08-19 1995-06-22 Scroll compressor

Country Status (6)

Country Link
EP (1) EP0697522A1 (en)
JP (1) JP3364016B2 (en)
KR (1) KR0156882B1 (en)
CN (1) CN1119704A (en)
AU (1) AU2183095A (en)
CA (1) CA2152454C (en)

Families Citing this family (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0732502B1 (en) * 1995-03-13 1999-10-13 Mitsubishi Jukogyo Kabushiki Kaisha Scroll type fluid machine
JP3918814B2 (en) * 2004-01-15 2007-05-23 ダイキン工業株式会社 Fluid machinery
JP4972952B2 (en) * 2006-02-17 2012-07-11 ダイキン工業株式会社 Fluid machinery
JP5039327B2 (en) 2006-06-14 2012-10-03 三菱重工業株式会社 Scroll compressor
JP2008286135A (en) * 2007-05-18 2008-11-27 Denso Corp Compressor
JP5358018B2 (en) * 2010-02-18 2013-12-04 東芝キヤリア株式会社 Rotary compressor and refrigeration cycle apparatus
JP5767959B2 (en) 2011-12-22 2015-08-26 大豊工業株式会社 Sliding member
KR20150066530A (en) * 2012-10-05 2015-06-16 아사히 가라스 가부시키가이샤 Roller conveyor, plate body inspecting device, and glass plate manufacturing device
CN103089622A (en) * 2012-11-14 2013-05-08 柳州易舟汽车空调有限公司 Scroll compressor
JP2014196680A (en) * 2013-03-29 2014-10-16 株式会社日立製作所 Refrigerant compressor
JP6442171B2 (en) * 2014-06-27 2018-12-19 三菱重工サーマルシステムズ株式会社 Scroll compressor
KR101783095B1 (en) 2015-08-24 2017-10-24 서울특별시 System and method of controling sequentially water clarifying place
CN114837947A (en) * 2022-05-05 2022-08-02 江苏太平洋精锻科技股份有限公司 Anti-rotation mechanism of air conditioner compressor of electric automobile

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0617674B2 (en) * 1983-11-09 1994-03-09 株式会社日立製作所 Scroll fluid machinery
JPS6140357A (en) * 1984-07-31 1986-02-26 Otsuka Chem Co Ltd Polyphenylene sulfide resin composition
JPH02197506A (en) * 1989-01-25 1990-08-06 Toshiba Corp Production of scroll vane

Also Published As

Publication number Publication date
JP3364016B2 (en) 2003-01-08
KR0156882B1 (en) 1999-01-15
AU2183095A (en) 1996-02-29
KR960008057A (en) 1996-03-22
CN1119704A (en) 1996-04-03
CA2152454A1 (en) 1996-02-20
JPH0861256A (en) 1996-03-08
EP0697522A1 (en) 1996-02-21

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Effective date: 20150622