Metal working – Method of mechanical manufacture – Prime mover or fluid pump making
Reexamination Certificate
1999-06-02
2001-03-06
Cuda, I (Department: 3726)
Metal working
Method of mechanical manufacture
Prime mover or fluid pump making
C029S888020, C418S063000
Reexamination Certificate
active
06195889
ABSTRACT:
BACKGROUND OF INVENTION
This invention pertains to hermetically sealed, positive displacement compressors for compressing refrigerant in refrigeration systems such as air conditioners, refrigerators and the like. In particular, the invention describes a rotary compressor mechanism of the type which includes a cylinder block having a cylindrical cavity, a bearing assembly and a motor assembly driving a roller piston disposed in the cylindrical cavity. More particularly, the cylinder block includes a vane slot extending completely axially through the cylinder block to accommodate a reciprocating vane therein and the vane being urged against the roller piston.
Rotary compressors are well known in the art, as exemplified by U.S. Pat. No. 4,889,475 which is assigned to assignee of the present application. Generally, the tolerances between the reciprocating vane and the slot sidewalls defining the vane slot of the cylinder block must be tightly controlled in order to optimize compressor efficiency. Proper vane clearances are necessary to allow free reciprocation of the vane in its slot and to allow sealing against discharge pressure gas blow-by therebetween. Maintaining these clearances in previous compressors often requires precision vane and/or slot machining, or select fitting of the individual vanes and cylinder blocks. A disadvantage arising from precision machining of the slot and/or vane is the associated cost of precision machining a pair of sidewalls defining the vane slot and vane. Always existent with precision machining is the immense cost associated with the act of “scrapping a part” when one of the final operations is spoiled due to a myriad of possible and easily made mistakes. A structure and method for easily providing uniform clearances between the vanes and their slots without resorting to costly and time consuming machining operations or select fitting is needed.
Generally, rotary compressor assembly entails first, laboriously preparing the vane and vane slot for an introduction of the vane into the vane slot, and second, the vane is introduced into the vane slot. A disadvantage, already mentioned hereinabove, is that laboriously preparing components, through precision machining and the like, has an increased cost associated therewith. Therefore, if components, such as the vane and vane slot, required less labor and the precise relationship required between the vane and vane slot were sustained through an inventive method of assembly, this inventive method would be highly desirous.
SUMMARY OF THE INVENTION
The present invention overcomes the disadvantages of the prior art described above by providing a rotary compressor assembly as herein described.
The present invention rotary compressor assembly is hermetically sealed and comprises a housing, a cylinder block and a bearing assembly disposed within the housing. The cylinder block and the bearing assembly define a cylindrical cavity which has a roller piston disposed therein. The rotary compressor assembly includes a motor drivingly coupled to the roller piston.
The present invention rotary compressor assembly also includes the cylinder block having a vane slot extending completely axially through the cylinder block and extending radially from an outside perimeter surface of the cylinder block to the cylindrical cavity. At least a portion of the vane slot is defined by a pair of substantially parallel sidewalls and a vane is disposed in and guided by the vane slot and is urged against said roller piston. The cylinder block, of the present invention rotary compressor assembly, is in a state of circumferentially oriented stress and is fixed in that state of stress.
The present invention also includes a method to assemble a rotary compressor assembly which include steps, one step being, spreading apart the sidewalls of the vane slot in the cylinder block. Another step includes inserting into the spread apart slot a gauge vane of thickness greater than the thickness of a reciprocating vane. Yet another step includes releasing the block to cause the slot sidewalls to engage the gauge vane. Remaining steps include fixing the cylinder block to hold the sidewalls substantially parallel, removing the gauge vane from the slot, and inserting the reciprocating vane in the slot, whereby a clearance is maintained between the reciprocating vane and slot sidewalls.
The present invention also provides yet another method to assemble a rotary compressor assembly which includes steps, one being, inserting into the vane slot in the cylinder block the gauge vane of thickness greater than a thickness of the reciprocating vane. Another step includes closing together sidewalls of the vane slot in the cylinder block to cause the slot sidewalls to engage the gauge vane with the cylinder block. Also included are the steps of fixing the cylinder block to hold the sidewalls substantially parallel, removing the gauge vane from the slot, and inserting the reciprocating vane in the slot, whereby a clearance is maintained between the reciprocating vane and slot sidewalls.
REFERENCES:
patent: 2758546 (1956-08-01), Gillette
patent: 3791780 (1974-02-01), Fritch et al.
patent: 4396365 (1983-08-01), Hayashi
patent: 4605362 (1986-08-01), Sturgeon et al.
patent: 4649612 (1987-03-01), Sakamaki et al.
patent: 4706353 (1987-11-01), Zgliczynski et al.
patent: 4790733 (1988-12-01), Vaccaro
patent: 5040946 (1991-08-01), Caoduro
patent: 5218762 (1993-06-01), Netto Da Costa
patent: 5314318 (1994-05-01), Hata et al.
patent: 5573376 (1996-11-01), Hayden et al.
patent: 60-101289 (1985-06-01), None
patent: 61-028784 (1986-02-01), None
patent: 61-258987 (1986-11-01), None
patent: 1-305188 (1989-12-01), None
patent: 5-79485 (1993-03-01), None
Baker & Daniels
Cuda I
Tecumseh Products Company
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