BACKGROUND OF THE INVENTION
The present invention relates to a compressor and, more particularly, to a compressor including a retainer gasket and a discharge valve forming plate.
Japanese Patent Application Publication No. 11-230040 discloses a swash plate type compressor used for a vehicle air conditioner. Referring to FIG. 14, a swash plate type compressor 71 includes a cylinder assembly 76 formed by joining a gasket 88 to the rear end surface of the front cylinder block 76A and joining the front end surface of a rear cylinder block 76B to the gasket 88. A front housing 77 is provided on the front end surface of the front cylinder block 76A and a rear housing 78 is provided on the rear end surface of the rear cylinder block 76B. A plurality of columnar cylinder bores 75 are formed in the cylinder assembly 76. A piston 74 which reciprocates in the cylinder bore 75 is provided in the cylinder bore 75. The piston 74 is connected to a swash plate 73 through a shoe 89. The swash plate 73 is mounted on a drive shaft 72 provided in the center of the cylinder assembly 76. A suction chamber 79 and a discharge chamber 80 are provided in the front housing 77 and the rear housing 78, respectively. Valve plates 81 are provided between both the end surfaces of the cylinder assembly 76 and the front and the rear housings 77 and 78, respectively.
Suction valve forming plates 82 including suction valves and gaskets 83 are provided between the valve plates 81 and both the end surfaces of the cylinder assembly 76, respectively. Discharge valve forming plates 84 having a flat plate shape and including discharge valves and retainer gaskets 85 are provided between the valve plate 81 and the front and the rear housings 77 and 78, respectively.
A sectional view of a state of assembly of the valve plate 81 and the discharge valve forming plate 84 is shown in FIG. 15. A plurality of dowels 86 are formed on the valve plate 81. Positioning holes 87 are formed in the discharge valve forming plate 84. When assembling the valve plate 81 and the discharge valve forming plate 84, the dowels 86 of the valve plate 81 are inserted into and fit in the positioning holes 87 of the discharge valve forming plate 84 and the distal ends of the dowels 86 are caulked to be expanded in the entire radial direction to integrally fix the valve plate 81 and the discharge valve forming plate 84. Consequently, assembly work for the compressor is made efficient.
However, in the swash plate type compressor 71 described in the above-described Publication, the dowels 86 need to be formed on the valve plate 81. As shown in FIG. 14, the compressor 71 being assembled is required to have high airtightness on contact surfaces of the valve plates 81, the suction valve forming plates 82, the gaskets 83 and the retainer gaskets 85. Among these members, the valve plate 81, which is thick and has high rigidity compared with the other members, is required to have high flatness in order to prevent leakage of gas. In order to ensure flatness, polishing is applied to the valve plate 81. However, a sophisticated technology is required to perform the polishing while leaving convex portions in the valve plate 81, leading to an increase in manufacturing costs.
The present invention is directed to providing a compressor which has a simple configuration and is formed by efficient assembly work.
SUMMARY OF THE INVENTION
In accordance with the present invention, a compressor includes a housing, a cylinder block, a valve plate, a discharge valve forming plate and a retainer gasket. A suction chamber and a discharge chamber are formed in the housing. A compression chamber is formed in the cylinder block. The valve plate includes a discharge port. The discharge chamber and the compression chamber communicate with each other through the discharge port. The discharge valve forming plate has a flat plate shape and includes a discharge valve, a connecting portion and a discharge valve engaging portion. The discharge valve is configured to open and close the discharge port. A plurality of discharge valve support portions extends from the connecting portion to support the discharge valve. The discharge valve engaging portion extends from the connecting portion. The retainer gasket includes a retainer, a gasket and a retainer gasket engaging portion. The retainer is configured to restrict an opening and closing operation of the discharge valve. The gasket is configured to ensure airtightness between the housing and the cylinder block. The retainer gasket engaging portion is formed by bending a part of the retainer gasket. The discharge valve forming plate and the retainer gasket are positioned by connecting the discharge valve engaging portion and the retainer gasket engaging portion.
Other aspects and advantages of the invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:
FIG. 1 is a sectional view of a reciprocating compressor according to a first preferred embodiment of the present invention;
FIG. 2 is a sectional view taken along the line II-II in FIG. 1;
FIG. 3 is a plan view of a valve plate of the reciprocating compressor of FIG. 1;
FIG. 4 is a plan view of a retainer gasket of the reciprocating compressor of FIG. 1;
FIG. 5 is a partially enlarged view of retainer gasket projections of the reciprocating compressor of FIG. 1;
FIG. 6 is a partial sectional view taken along the line VI-VI in FIG. 5;
FIG. 7 is a plan view of a discharge valve forming plate of the reciprocating compressor of FIG. 1;
FIG. 8 is a sectional view taken along the line VIII-VIII in FIG. 1;
FIG. 9 is an enlarged sectional view showing a state in which the retainer gasket projections and discharge valve forming plate projections are combined in the reciprocating compressor of FIG. 1;
FIG. 10 is a plan view of a valve plate of a reciprocating compressor according to a second preferred embodiment of the present invention;
FIG. 11 is an enlarged sectional view taken along the line XI-XI in FIG. 10 showing a state in which valve plate projections, retainer gasket projections, and discharge valve forming plate projections are combined in the reciprocating compressor of FIG. 10;
FIG. 12 is a partial sectional view of the front end of a front cylinder block of a reciprocating compressor according to a third preferred embodiment of the present invention;
FIG. 13 is a partial sectional view of the rear end of a rear cylinder block of the reciprocating compressor of FIG. 12;
FIG. 14 is a sectional view of a conventional swash plate type compressor according to a background art; and
FIG. 15 is a sectional view showing a state of assembly of a valve plate and a discharge plate forming plate in the conventional swash plate type compressor of FIG. 14.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following will describe a compressor according to a first preferred embodiment of the present invention with referring to FIGS. 1 through 9. Referring to FIG. 1, reference numeral 1 designates a swash plate type compressor according to the first preferred embodiment of the present invention. The swash plate type compressor 1 (hereinafter referred to as “compressor”) includes a front cylinder block 3 and a rear cylinder block 4 which have a column shape. The front end surface of the rear cylinder block 4 is joined to the rear end surface of the front cylinder block 3 thereby to form a cylinder assembly 2 of the swash plate type compressor. The cylinder assembly 2 serves as a cylinder block of the present invention. The front cylinder block 3 and the rear cylinder block 4 are formed of aluminum or aluminum alloy. A front housing 5 is provided on the front end surface of the front cylinder block 3 through a front valve port assembly 10 for covering the front end surface of the front cylinder block 3. A rear housing 6 is provided on the rear end surface of the rear cylinder block 4 through a rear valve port assembly 11 for covering the rear end surface of the rear cylinder block 4. The front and the rear housings 5 and 6 are formed of aluminum or an aluminum alloy. The front and the rear housings 5 and 6 serve as a housing of the present invention.
Shaft holes 7 and 8 are formed through the front and the rear cylinder blocks 3 and 4 so as to extend through the centers of the front and the rear cylinder blocks 3 and 4. A drive shaft 9 is inserted in the shaft holes 7 and 8. The drive shaft 9 is rotatably supported by sealing surfaces (not shown) formed on the surfaces of the shaft holes 7 and 8. Holes 12 and 13 are formed in the front and the rear valve port assemblies 10 and 11 at the center thereof, respectively. The drive shaft 9 is formed extending through the holes 12 and 13. The axis extending from the center of the circle of the upper surface of the columnar front cylinder block 3 to the center of the circle of the bottom surface of the columnar rear cylinder block 4 and the axis of the drive shaft 9 coincide with each other. The axes are represented as a center axis L. A space between the inner surface of the front housing 5 and the drive shaft 9 is sealed by a shaft seal 14.
A swash plate 16 formed of aluminum or an aluminum alloy is mounted to the drive shaft 9 around the axial center of the drive shaft 9. The swash plate 16 includes an annular base 17 and a boss 18 formed obliquely to the drive shaft 9. The swash plate 16 is accommodated in the crank chamber 19 which is formed in the front and the rear cylinder blocks 3 and 4 and includes front and rear end surfaces 54 and 55. A thrust bearing 20 is provided between the front end surface 54 of the crank chamber 19 and the base 17 of the swash plate 16. A thrust bearing 21 is provided between the rear end surface 55 of the crank chamber 19 and the base 17 of the swash plate 16. The thrust bearings 20 and 21 restricts the movement of the swash plate 16 in the axial direction of the drive shaft 9. The thrust bearings 20 and 21 are pressed against the front and the rear end surfaces 54 and 55, respectively.
Referring to FIG. 2, three front cylinder bores 22 are formed in the front cylinder block 3 at equal intervals around the drive shaft 9. Similarly, as shown in
FIG. 1, three rear cylinder bores 23 are formed in the rear cylinder block 4 at equal intervals around the drive shaft 9 (only one is shown in FIG. 1). The front cylinder bores 22 and the rear cylinder bores 23 are arranged to be paired in the axial direction of the drive shaft 9. A double-headed piston 24 is accommodated in the front and the rear cylinder bores 22 and 23. The front cylinder bores 22 are closed by the front valve port assembly 10 and the double-headed pistons 24. The rear cylinder bores 23 are closed by the rear valve port assembly 11 and the double-headed pistons 24.
The rotation of the swash plate 16 integrally rotating with the drive shaft 9 is transmitted to the double-headed pistons 24 through a pair of shoes 25 provided to hold the boss 18. The double-headed pistons 24 reciprocate in the front and the rear cylinder bores 22 and 23. Front compression chambers 26 are formed in the front cylinder bores 22 between the front valve port assembly 10 and the double-headed pistons 24, respectively. Rear compression chambers 27 are formed in the rear cylinder bores 23 between the rear valve port assembly 11 and the double-headed pistons 24, respectively.
The following will describe a front suction mechanism and a front discharge mechanism of the compressor 1. As shown in FIG. 1, three front suction chambers 28 are formed in the front housing 5 and the front cylinder block 3 so as to surround the drive shaft 9 and extend through the front valve port assembly 10 (only one is shown in FIG. 1). Each front suction chamber 28 is provided between the adjacent front cylinder bores 22 (refer to FIG. 2). Each front suction chamber 28 communicates with an accommodation chamber 15 formed in the front housing 5 through a passage (not shown).
Front discharge chambers 30 are respectively provided radially outward of the front suction chambers 28 on the circular cross-section of the front cylinder block 3 perpendicular to the center axis L of the drive shaft 9. Each front discharge chamber 30 extends through the front valve port assembly 10 and into the front cylinder block 3. Front discharge chambers 29 are provided so as to face the front compression chambers 26, respectively. Each front discharge chamber 29 and the corresponding front discharge chamber 30 communicate with each other through a passage (not shown).
The following will describe a rear suction mechanism and a rear discharge mechanism of the compressor 1. As shown in FIG. 1, three rear suction chambers 32 are formed around the drive shaft 9 in the rear housing 6 and the rear cylinder block 4 so as to extend into the rear housing 6 through the rear valve port assembly 11 (one is shown in FIG. 1). Each rear suction chamber 32 is provided between the adjacent rear cylinder bores 23, as in the case of the front suction chambers 28. Rear discharge chambers 34 are formed in the rear housing 6 so as to face the corresponding rear compression chambers 27, respectively. A rear housing-side suction chamber 33 is formed in the rear housing 6 at the center thereof. The front suction chamber 28, the rear suction chamber 32 and the rear housing-side suction chamber 33 serve as a suction chamber of the present invention. The front discharge chamber 29, the front discharge chamber 30, the rear discharge chamber 34 and the rear discharge chamber 35 serve as a discharge chamber of the present invention. The front compression chamber 26 and the rear compression chamber 27 serve as a compression chamber of the present invention.
Rear discharge chambers 35 are provided radially outward of the rear suction chambers 32 on the circular cross-section of the rear cylinder block 4 perpendicular to the center axis L of the drive shaft 9 (only one rear discharge chamber 35 is shown in FIG. 1). The rear discharge chambers 35 extend through the rear valve port assembly 11 and into the rear housing 6. Discharge ports 31 are formed in the rear valve port assembly 11 so as to face the rear discharge chambers 34. Each rear discharge chamber 34 and the corresponding rear compression chamber 27 communicate with each other through the corresponding discharge port 31. Discharge valves 52B are provided in the rear discharge chambers 34 for opening and closing the discharge ports 31, respectively. Each rear discharge chamber 34 and the corresponding rear discharge chamber 35 communicate with each other through a passage (not shown).
A suction passage 36 is provided in the front and the rear cylinder blocks 3 and 4. The suction passage 36 communicates with one front suction chamber 28 and one rear suction chamber 32. An inlet 37 is formed through the front cylinder block 3. One end of the inlet 37 is opened through the outer circumferential surface of the front cylinder block 3 and the other end of the inlet 37 is opened through the inner circumferential surface of the suction passage 36. One opening of the inlet 37 is connected to a circuit wire 38 of an external refrigerant circuit provided outside the compressor 1.
The following will describe the front valve port assembly 10 and the rear valve port assembly 11 in detail. As shown in FIG. 1, the front valve port assembly 10 is formed of a discharge valve forming plate 42, a valve plate 43 and a retainer gasket 44, and the rear valve port assembly 11 is formed of a discharge valve forming plate 42, a valve plate 43 and a retainer gasket 44. The valve plates 43 are a partitioning wall for partitioning the front compression chambers 26 and the front discharge chambers 29 and a partition wall for partitioning the rear compression chambers 27 and the rear discharge chambers 34. The discharge valve forming plate 42 is arranged between the valve plate 43 and the retainer gasket 44. The front valve port assembly 10 is formed such that the valve plate 43 and the front cylinder block 3 are adjacent to each other and the front housing 5 and the retainer gasket 44 are adjacent to each other. The rear valve port assembly 11 has the same structure as the front valve port assembly 10. The rear valve port assembly 11 is formed such that the valve plate 43 and the rear cylinder block 4 are adjacent to each other and the rear housing 6 and the retainer gasket 44 are adjacent to each other. As shown in FIG. 3, discharge ports 31 are provided in the valve plates 43 so as to face the corresponding front cylinder bores 22 and the corresponding rear cylinder bores 23 (refer to FIG. 1), respectively, and bolt holes 58 are provided in the valve plates 43 for fixing the valve plates 43 to the front and the rear cylinder blocks 3 and 4 (refer to FIG. 1), respectively. Valve plate suction ports 57 are formed in the valve plates 43 such that each valve plate suction port 57 is positioned between the adjacent discharge ports 31. Valve plate discharge ports 56 are provided in the valve plates 43 radially outward of the valve plate suction ports 57.
As shown in FIG. 4, the retainer gasket 44 is formed in a thin disc shape. The circumference of the side edge of the retainer gasket 44 is formed by a gasket 61. The gaskets 61 function to ensure airtightness between the front housing 5 and the front cylinder block 3 (refer to FIG. 1) and between the rear housing 6 and the rear cylinder block 4 (refer to FIG. 1), respectively. Retainer gasket discharge ports 50 are formed in the gasket 61 so as to have a shape projecting in three directions. Three retainers 49, one ends of which are connected to the gasket 61, are arranged at equal intervals in the circumferential direction of the retainer gasket 44 so as to face the corresponding front cylinder bores 22 and the corresponding rear cylinder bores 23 (refer to FIG. 1), respectively. A retainer gasket inner frame 62 is provided in the retainer gasket 44 radially inward of the retainer gasket discharge ports 50. The retainer gasket inner frame 62 is formed to have a thin belt-like shape of a closed loop projecting in three directions. A retainer gasket suction port 51 is formed in the retainer gasket 44 radially inward of the retainer gasket inner frame 62 so as to have a shape projecting in three directions. The retainer gasket inner frame 62 is connected to the other ends of the retainers 49. Pairs of two retainer gasket projections 45 are provided in projecting portions of the retainer gasket inner frame 62, respectively. The retainer gasket projection 45 serves as a retainer gasket engaging portion of the present invention. The retainers 49 are formed in the retainer gasket 44 by press working and, simultaneously, the retainer gasket projections 45 are formed by bending a part of the retainer gasket inner frame 62 by press working. Therefore, another process is not required for forming the retainer gasket projections 45. Six bolt holes 46 are provided in the gasket 61 for mounting the retainer gasket 44 to the valve plate 43 (refer to FIG. 1). As shown in FIG. 5, each retainer gasket projection 45 includes a distal end 45A. The distal ends 45A of the retainer gasket projections 45 are formed into a shape projecting in a substantially arcuate shape toward the paired retainer gasket projection 45, respectively. One pair of the distal ends 45A of the retainer gasket projections 45 forms an engaging portion. As shown in FIG. 6, the retainer gasket projection 45 is formed substantially perpendicular to the plane of the retainer gasket 44.
As shown in FIG. 7, the discharge valve forming plate 42 includes a connecting portion 64 having a thin belt-like frame shape of a closed loop projecting in three directions. The discharge valve forming plate 42 includes a discharge valve forming plate suction port 53 formed inside the discharge valve forming plate 42. Discharge valve supports 52A are formed in the connecting portion 64 of the discharge valve forming plate 42 to extend to the outer side of the discharge valve forming plate 42 at three positions where the connecting portion 64 of the discharge valve forming plate 42 is bent to the inner side of the discharge valve forming plate 42. The discharge valves 52B are provided at the distal ends of the discharge valve supports 52A, respectively. That is, the discharge valve support 52A supports the corresponding discharge valve 52B. The discharge valves 52B are provided at positions respectively overlapping the retainers 49 when the discharge valve forming plate 42 and the retainer gasket 44 (refer to FIG. 4) are overlapped with each other. The retainer 49 restricts the opening and closing operation of the discharge valve 52B. Discharge valve forming plate projections 47 are respectively formed in the discharge valve forming plate 42 at the center of the connecting portions 64 so as to extend from the connecting portion 64 toward the inner side of the discharge valve forming plate 42. The discharge valve forming plate projections 47 are formed on a plane which is the same as the plane of the discharge valve forming plate 42. The discharge valve forming plate projection 47 serve as a discharge valve engaging portion of the present invention.
The following will describe a method of assembling the front and the rear valve port assemblies 10 and 11 when assembling the compressor 1, in detail. As shown in FIG. 8, when the valve plate 43, the discharge valve forming plate 42, and the retainer gasket 44 are combined to assemble the front valve port assembly 10 (and the rear valve port assembly 11), the valve plate 43, the discharge valve forming plate 42 and the retainer gasket 44 are overlapped with one another. As shown in FIG. 9, the valve plate 43, the discharge valve forming plate 42 and the retainer gasket 44 are connected with one another such that the discharge valve forming plate projection 47 is inserted between one pair of the retainer gasket projections 45 so as to pass through between the distal ends 45A of the retainer gasket projections 45. The distal ends 45A of the retainer gasket projections 45 projecting from the plane of the discharge valve forming plate 42 are inserted into the valve plate suction ports 57 along a suction port inner wall surface 65 (refer to FIG. 3) of the valve plate 43 and accommodated in the valve plate suction ports 57. The valve plate suction port 57 serves as an accommodating portion. One discharge valve forming plate projection 47 is inserted between one pair of the retainer gasket projections 45 and, therefore, the positioning of the retainer gasket 44 and the discharge valve forming plate 42 may be reliably performed. As shown in FIG. 5, the distal ends 45A of one pair of the retainer gasket projections 45 are machined into a shape projecting in a substantially arcuate shape toward the inner side of the paired retainer gasket projections 45. The width of the discharge valve forming plate projections 47 (refer to FIG. 7) is machined slightly wider than the distance between the distal ends 45A of one pair of the retainer gasket projections 45. Therefore, when the retainer gasket 44 and the discharge valve forming plate 42 are overlapped with each other, the discharge valve forming plate projection 47 is inserted between one pair of the retainer gasket projections 45 thereby to expand the distance between the distal ends 45A of one pair of the retainer gasket projections 45. After the discharge valve forming plate projection 47 passes through between the distal ends 45A of one pair of the retainer gasket projections 45, the distal ends 45A of the retainer gasket projections 45 are returned to the original position due to the elasticity thereof. Similarly, the other two discharge valve forming plate projections 47 are inserted between the other two pairs of the retainer gasket projections 45, respectively, so that the retainer gasket 44 and the discharge valve forming plate 42 may easily positioned and engaged with each other. Consequently, work efficiency may be improved and a work time can be reduced. The assembling can be performed more easily than the assembling with machining of dowels or the like in the valve plate 43. Further, the retainer gasket 44 and the discharge valve forming plate 42 may be prevented from falling off during assembly work.
The discharge valve forming plate 42 and the retainer gasket 44 are positioned by connecting the discharge valve forming plate projections 47 and the retainer gasket projections 45 with each other. Therefore, the assembly work for the compressor 1 may be made efficient.
According to the first preferred embodiment, the retainer gasket 44 includes at least one pair of two retainer gasket projections 45 and the discharge valve forming plate 42 includes at least one discharge valve forming projection 47. Alternatively, the retainer gasket 44 may include at least one retainer gasket projection 45, the discharge valve forming plate 42 may include at least one pair of two discharge valve forming plate projections 47 and the retainer gasket projection 45 may be inserted between the discharge valve forming plate projections 47. In this case, the advantageous effects which is the same as the advantageous effects in the first preferred embodiment may be obtained.
The following will describe a compressor according to a second preferred embodiment of the present invention. In the following second and other preferred embodiments, like reference numerals or symbols denote the like elements or parts of the compressor used in the description of the first preferred embodiment and the detailed description of such elements or parts will be omitted. In the compressor according to the second preferred embodiment of the present invention, positioning of the valve plate, the retainer gasket and the discharge valve forming plate may be performed.
As shown in FIG. 10, the valve plate 43 includes valve plate projections 59 respectively formed on the edges of the valve plate suction ports 57 located radially outward of the valve plate 43. The valve plate projection 59 serves as an accommodating and engaging portion. The valve plate projections 59 are formed to be on the same plane as the valve plate 43. Other structures are the same as the first preferred embodiment.
As shown in FIG. 11, when assembling the front and the rear valve port assemblies 10 and 11, the discharge valve forming plate 42 is overlapped with the valve plate 43, and the retainer gasket 44 is overlapped with the discharge valve forming plate 42. In the assembling, the discharge valve forming plate projection 47 and the valve plate projection 59 are inserted between one pair of the retainer gasket projections 45. As in the first preferred embodiment, the discharge valve forming plate projection 47 and the valve plate projection 59 are inserted between the retainer gasket projections 45 such that the discharge valve forming plate projection 47 pass through between the distal ends 45A and the valve plate projection 59 is inserted between the distal ends 45A. Consequently, the positioning of the valve plate 43, the retainer gasket 44 and the discharge valve forming plate 42 may be easily performed when assembling the valve plate 43, the retainer gasket 44 and the discharge valve forming plate 42. Further, after the valve plate 43, the retainer gasket 44, and the discharge valve forming plate 42 are overlapped with one another, the valve plate 43, the retainer gasket 44 and the discharge valve forming plate 42 are engaged with one another. Therefore, the valve plate 43, the retainer gasket 44 and the discharge valve forming plate 42 are prevented from falling off and may be handled as one body. Consequently, work efficiency may be improved.
The following will describe a compressor according to a third preferred embodiment of the present invention. In the compressor according to the third preferred embodiment of the present invention, the valve plate and the cylinder block are integrally formed.
As shown in FIG. 12, a valve plate 63A is integrally formed with the front end of the front cylinder block 3. As shown in FIG. 13, a valve plate 63B is integrally formed with the rear end of the rear cylinder block 4. The surface of the valve plate 63A facing the front housing 5 and the surface of the valve plate 63B facing the rear housing 6 have a structure which is the same as the structure of the surface of the valve plate 43 of the second preferred embodiment (refer to FIG. 10). Other structures are the same as the second preferred embodiment.
When assembling the compressor 1, as shown in FIG. 11, the assembly is performed in the same manner as the second preferred embodiment. Consequently, the valve plates 63A and 63B (refer to FIGS. 12 and 13), the retainer gasket 44 and the discharge valve forming plate 42 may be easily positioned when assembling. Further, work efficiency for engaging the valve plates 63A and 63B, the retainer gasket 44 and the discharge valve forming plate 42 with one another may be improved.
According to the first through the third preferred embodiments of the present invention, the compressor 1 is a swash plate type compressor employing a gas suction system using a rotary valve. Alternatively, the compressor 1 may be swash plate type compressors of other systems and the compressor 1 is not limited to the swash plate type and may be any compressor as long as the compressor includes a piston. According to the first through the third preferred embodiments of the present invention, three pairs of the retainer gasket projections 45 are provided and three discharge valve forming plate projections 47 and three valve plate projections 59 are provided. Alternatively, at least one pair of the retainer gasket projections 45 may be provided and at least one of any one of the discharge valve forming plate projections 47 and the valve plate projections 59 may be provided with respect to the retainer gasket projections 45. Further, according to the first through the third preferred embodiments of the present invention, the distal ends 45A of one pair of the retainer gasket projections 45 are machined into the shape projecting in the substantially arcuate shape toward the inner side of the paired retainer gasket projections 45. Alternatively, the distal ends 45A may be projected in a shape other than the substantially arcuate shape.
Patent Application
20140294637
