Method for processing contact portions between valve plate and suction valve and/or discharge valve of reciprocating compressor, and reciprocating compressor
The present invention relates to a method for processing contact portions between a valve plate and a suction valve and/or discharge valve of a reciprocating compressor, and a reciprocating compressor.
Patent Document No. 1 teaches a method for processing contact portions between a valve plate and a suction valve and/or discharge valve of a reciprocating compressor to prevent the suction valve and/or the discharge valve from sticking on the valve plate at the portions contacting the valve plate, wherein the compressor comprises a cylinder bore, a piston fitted in the cylinder bore to be capable of reciprocal movement, a valve plate provided with a suction hole and a discharge hole communicating with the cylinder bore, a strap-shaped suction valve for opening and closing the suction hole, a strap-shaped discharge valve for opening and closing the discharge hole, a suction chamber communicating with the cylinder bore through the suction hole and the suction valve, and a discharge chamber communicating with the cylinder bore through the discharge valve and the discharge hole, and wherein the method comprises the steps of melting and sputtering the portion of the end face of the valve plate contacting the suction valve around the suction hole by laser beam machining and/or the portion of the end face of the valve plate contacting the discharge valve around the discharge hole by laser beam machining, and projecting the non-laser-beam-machined-portions from the laser-beam-machined-portions.
The method of the Patent Document No. 1 has various advantages over the conventional processing method wherein projections are made by shot blasting, including, for example, that the processing media do not remain, the projections are formed precisely, etc.
The method of the Patent Document No. 1 has a disadvantage in that the productivity is low because precise processing is required to melt and sputter a part of the valve plate, and thereby form the projections.
The present invention is directed to solving the aforementioned problem. An object of the present invention is to provide a method for processing contact portions between a valve plate and a suction valve and/or discharge valve of a reciprocating compressor to prevent the suction valve and/or the discharge valve from sticking on the valve plate at the portions contacting the valve plate, wherein the compressor comprises a cylinder bore, a piston fitted in the cylinder bore to be capable of reciprocal movement, a valve plate provided with a suction hole and a discharge hole communicating with the cylinder bore, a strap-shaped suction valve for opening and closing the suction hole, a strap-shaped discharge valve for opening and closing the discharge hole, a suction chamber communicating with the cylinder bore through the suction hole and the suction valve, and a discharge chamber communicating with the cylinder bore through the discharge valve and the discharge hole, and wherein the productivity is higher than that in the method of the Patent Document No. 1.
In accordance with the present invention, there is provided a method for processing contact portions between a valve plate and a suction valve and/or discharge valve of a reciprocating compressor to prevent the suction valve and/or the discharge valve from sticking on the valve plate at the portions contacting the valve plate, wherein the compressor comprises a cylinder bore, a piston fitted in the cylinder bore to be capable of reciprocal movement, a valve plate provided with a suction hole and a discharge hole communicating with the cylinder bore, a strap-shaped suction valve for opening and closing the suction hole, a strap-shaped discharge valve for opening and closing the discharge hole, a suction chamber communicating with the cylinder bore through the suction hole and the suction valve, and a discharge chamber communicating with the cylinder bore through the discharge valve and the discharge hole, and wherein the method comprises the steps of quenching the portion of the end face of the valve plate contacting the suction valve near the suction hole and/or the portion of the end face of the valve plate contacting the discharge valve near the discharge hole by laser beam machining without melting them, and grinding the end face of the valve plate contacting the suction valve and/or the end face of the valve plate contacting the discharge valve to project the quenched portions from the remaining unquenched portions.
In another aspect of the present invention, there is provided a method for processing contact portions between a valve plate and a suction valve and/or discharge valve of a reciprocating compressor to prevent the suction valve and/or the discharge valve from sticking on the valve plate at the portions contacting the valve plate, wherein the compressor comprises a cylinder bore, a piston fitted in the cylinder bore to be capable of reciprocal movement, a valve plate provided with a suction hole and a discharge hole communicating with the cylinder bore, a strap-shaped suction valve for opening and closing the suction hole, a strap-shaped discharge valve for opening and closing the discharge hole, a suction chamber communicating with the cylinder bore through the suction hole and the suction valve, and a discharge chamber communicating with the cylinder bore through the discharge valve and the discharge hole, and wherein the method comprises the steps of quenching the portion of the end face of the suction valve contacting the valve plate opposing the portion of the valve plate near the suction hole and/or the portion of the end face of the discharge valve contacting the valve plate opposing the portion of the valve plate near the discharge hole by laser beam machining without melting them, and grinding the end face of the suction valve and/or the end face of the discharge valve to project the quenched portions from the remaining unquenched portions.
In the present invention, a portion of the valve plate, or the suction valve, or the discharge valve is quenched by laser beam machining without being melted, and the valve plate, or the suction valve, or the discharge valve is ground to form a projection. Therefore, the productivity is higher in the present invention than that in the conventional method, wherein the valve plate is melted and sputtered partially to form projections.
In accordance with the present invention, there is provided a method for processing contact portions between a valve plate and a suction valve and/or discharge valve of a reciprocating compressor to prevent the suction valve and/or the discharge valve from sticking on the valve plate at the portions contacting the valve plate, wherein the compressor comprises a cylinder bore, a piston fitted in the cylinder bore to be capable of reciprocal movement, a valve plate provided with a suction hole and a discharge hole communicating with the cylinder bore, a strap-shaped suction valve for opening and closing the suction hole, a strap-shaped discharge valve for opening and closing the discharge hole, a suction chamber communicating with the cylinder bore through the suction hole and the suction valve, and a discharge chamber communicating with the cylinder bore through the discharge valve and the discharge hole, and wherein the method comprises the step of making any one of a resin coat, plated metal coat, thermal sprayed material coat, sintered metal coat and ceramic coat on the portion of the end face of the valve plate contacting the suction valve near the suction hole and/or the portion of the end face of the valve plate contacting the discharge valve near the discharge hole to project the coated portions from the remaining uncoated portions.
In another aspect of the present invention, there is provided a method for processing contact portions between a valve plate and a suction valve and/or discharge valve of a reciprocating compressor to prevent the suction valve and/or the discharge valve from sticking on the valve plate at the portions contacting the valve plate, wherein the compressor comprises a cylinder bore, a piston fitted in the cylinder bore to be capable of reciprocal movement, a valve plate provided with a suction hole and a discharge hole communicating with the cylinder bore, a strap-shaped suction valve for opening and closing the suction hole, a strap-shaped discharge valve for opening and closing the discharge hole, a suction chamber communicating with the cylinder bore through the suction hole and the suction valve, and a discharge chamber communicating with the cylinder bore through the discharge valve and the discharge hole, and wherein the method comprises the step of making any one of a resin coat, plated metal coat, thermal sprayed material coat, sintered metal coat and ceramic coat on the portion of the end face of the suction valve contacting the valve plate opposing the portion of the valve plate near the suction hole and/or the portion of the end face of the discharge valve contacting the valve plate opposing the portion of the valve plate near the discharge hole to project the coated portions from the remaining uncoated portions.
In the present invention, a portion of the valve plate, or the suction valve, or the discharge valve is provided with any one of a resin coat, plated metal coat, thermal sprayed material coat, sintered metal coat and ceramic coat to be projected. Therefore, the productivity is higher in the present invention than that in the conventional method, wherein the valve plate is melted and sputtered partially to form projections.
The portion near the suction hole may be any one of a continuous annular portion around the suction hole, an intermittent annular portion around the suction hole, a continuous arc portion extending along a part of the periphery of the suction hole, an intermittent arc portion extending along a part of the periphery of the suction hole, a continuous straight portion close to the periphery of the suction hole, and an intermittent straight portion close to the periphery of the suction hole. The portion near the discharge hole may be any one of a continuous annular portion around the discharge hole, an intermittent annular portion around the discharge hole, a continuous arc portion extending along a part of the periphery of the discharge hole, an intermittent arc portion extending along a part of the periphery of the discharge hole, a continuous straight portion close to the periphery of the discharge hole, and an intermittent straight portion close to the periphery of the discharge hole.
In a reciprocating compressor, wherein a plurality of cylinder bores are disposed to be circumferentially distanced from each other and located on the circumference of a first circle, a plurality of suction holes are disposed to be circumferentially distanced from each other and located on the circumference of a second circle, and a plurality of discharge holes are disposed to be circumferentially distanced from each other and located on the circumference of a third circle, it is possible to quench without melting the end face of the valve plate contacting the suction valves at an intermittent annular portion crossing all of the suction holes and/or the end face of the valve plate contacting the discharge valves at an intermittent annular portion crossing all of the discharge holes, or the end face of the valve plate contacting the suction valves at a continuous annular portion close to all of the suction holes and/or the end face of the valve plate contacting the discharge valves at a continuous annular portion close to all of the discharge holes by laser beam machining, and grind the end face of the valve plate contacting the suction valves and/or the end face of the valve plate contacting the discharge valves to project the quenched portions from the remaining unquenched portions. The productivity improves as the laser beam machining can be done by one pass or a small number of passes.
In a reciprocating compressor, wherein a plurality of cylinder bores are disposed to be circumferentially distanced from each other and located on the circumference of a first circle, a plurality of suction holes are disposed to be circumferentially distanced from each other and located on the circumference of a second circle, and a plurality of discharge holes are disposed to be circumferentially distanced from each other and located on the circumference of a third circle, it is possible to make any one of a resin coat, plated metal coat, thermal sprayed material coat, sintered metal coat and ceramic coat on the end face of the valve plate contacting the suction valves at an intermittent annular portion crossing all of the suction holes and/or the end face of the valve plate contacting the discharge valves at an intermittent annular portion crossing all of the discharge holes, or the end face of the valve plate contacting the suction valves at a continuous annular portion close to all of the suction holes and/or the end face of the valve plate contacting the discharge valves at a continuous annular portion close to all of the discharge holes to project the coated portions from the remaining uncoated portions. The productivity improves as the making of the coat can be done by one pass or a small number of passes.
If the width of the projection is too small, the projection wears easily. If the width of the projection is too large, the valve easily sticks on the projection. Therefore, the width of the projection is desirably 0.1 to 2.0 mm.
If the height of the projection is too small, the projection wears easily. If the height of the projection is too large, the valve is liable to close incompletely. Therefore, the height of the projection is desirably 0.01 to 0.5 mm.
If the surface roughness of the projection is too large, a gap is formed between the projection and the valve or the valve plate contacting the projection to cause leakage of gas during the compressing process or sucking process, thereby decreasing compression efficiency. Therefore, the surface roughness of the projection is desirably less than that of the remaining flat unquenched portions and desirably Rz10 or less.
If the difference of hardness between the quenched portion and the unquenched portion is small, no projection can be made by grinding. Therefore, the hardness of the quenched portion is desirably higher than that of the unquenched portions by HV100 or more.
A CO2 laser is suitable for the quenching process as its output is large.
A resin coat has an advantage in that it can be made easily. Among the various kinds of resin coats, a fluoride resin coat repels oil to suppress generation of oil film. Therefore, a fluoride resin coat is effective for preventing the suction valve and/or the discharge valve from sticking on the valve plate.
Desirably, a binder resin such as polyamideimide, epoxy, polyimide, polyamide, polyether ether ketone, etc. is used to enhance the adherence between the fluoride resin coat and the base material.
Forming the resin coat by screen printing is good in recovery of coating material.
Desirably, pre-coat treating such as chemical conversion treating. TuffLride processing, shot blasting, etc. is carried out on the base material to enhance the adherence between the resin coat and the base material.
A sintered metal coat has an advantage in that it is superior in wear resistance and peeling resistance. When the sintered metal coat is porous, it absorbs oil to suppress generation of oil film. Therefore, a porous sintered metal coat is effective for preventing the suction valve and/or discharge valve from sticking on the valve plate. When a porous sintered metal coat is used for preventing the suction valve and/or discharge valve from sticking on the valve plate, the porous sintered metal coat may cover the entire end surface of the valve plate opposing the suction valve and/or the discharge valve.
When the porous sintered metal coat is impregnated with PTFE, i.e., polytetrafluoroethylene, it repels oil to suppress generation of oil film. Therefore, the porous sintered metal coat impregnated with PTFE is effective for preventing the suction valve and/or discharge valve from sticking on the valve plate.
In the present invention, a portion of the valve plate, or the suction valve, or the discharge valve is quenched by laser beam machining without being melted, and the valve plate, or the suction valve, or the discharge valve is ground to form a projection. Therefore, the productivity is higher in the present invention than that in the conventional method, wherein the valve plate is melted and sputtered partially to form projections.
In the present invention, a portion of the valve plate, or the suction valve, or the discharge valve is provided with any one of a resin coat, plated metal coat, thermal sprayed material coat, sintered metal coat and ceramic coat to project. Therefore, the productivity is higher in the present invention than that in the conventional method, wherein the valve plate is melted and sputtered partially to form projections.
A method for processing contact portions between a valve plate and a suction valve and/or discharge valve of a reciprocating compressor in accordance with a preferred embodiment of the present invention will be described.
As shown in
The plurality of cylinder bores 2a are disposed circumferentially distanced from each other on the circumference of a first circle. The plurality of suction holes 8a are disposed circumferentially distanced from each other on the circumference of a second circle. The plurality of discharge holes 8b are disposed circumferentially distanced from each other on the circumference of a third circle.
The suction chamber 9a communicates with an evaporator of a car air conditioner not shown in
The discharge chamber 9b communicates with a condenser of a car air conditioner not shown in
A plurality of concaves 2b are formed on the end face of the cylinder block 2 opposing the valve plate 8 to restrict the lifts of the suction valves 10a.
As shown in
The continuous annular quenched portions may be constituted of many quenched dots made by a sharply focused thin laser beam or a quenched belt made by an unsharply focused thick laser beam.
As shown in
In the variable displacement swash plate compressor 1, the rotation shaft 5 is rotated by a car engine not shown in the Figures, the swash plate 6 rotates synchronously with the rotation of the rotation shaft 5, and the pistons 7 reciprocally move. Synchronously with the reciprocal movement of the pistons 7, coolant gas returns to the compressor from the evaporator of the car air conditioner, flows into the cylinder bores 2a through the suction port 9a′, the suction chamber 9a, the suction holes 8a and the suction valves 10a, becomes compressed in the cylinder bores 2a, and flows out of the compressor 1 to the condenser of the car air conditioner through the discharge holes 8b, the discharge valves 10b, the discharge chamber 9b and the discharge port 9b′.
In the variable displacement swash plate compressor 1, the end face of the valve plate 8 contacting the suction valves 10a is provided with projections at the portions near the suction holes 8a and the end face of the valve plate 8 contacting the discharge valves 10b is provided with projections at the portions near the discharge holes 8b. Therefore, the sticking of the suction valves 10a and the discharge valves 10b on the valve plate 8 caused by adhesion of lubricant oil dispersed in coolant gas is suppressed, delays in the opening actions of the suction valves 10a and the discharge valves 10b are prevented, and damage of the suction valves 10a and the discharge valves 10b and generation of noises caused by hard collisions between the tips of the suction valves 10a and the concaves 2b for restricting the lifts of the suction valves 10a and hard collisions between the discharge valves 10b and the valve retainers 11 due to delays in the opening actions of the suction valves 10a and the discharge valves 10b are prevented.
In the variable displacement swash plate compressor 1, some portions of the valve plate 8 are quenched by laser beam machining without being melted, and the valve plate 8 is ground to form projections. Therefore, the productivity of projection formation is high.
If the width of the projections is too small, the projections wear easily. If the width of the projections is too large, the valves easily stick on the projections. Therefore, the width of the projections is desirably 0.1 to 2.0 mm.
If the height of the projections is too small, the projections wear easily. If the height of the projections is too large, the valves are liable to close incompletely. Therefore, the height of the projections is desirably 0.01 to 0.5 mm.
If the surface roughness of the projections is too large, gaps are formed between the projections and the suction valves 10a and between the projections and the discharge valves 10b to cause leakage of gas during the compressing process or sucking process, thereby decreasing compression efficiency. Therefore, the surface roughness of the projections is desirably less than that of the remaining flat unquenched portions and desirably Rz10 or less.
If the difference of hardness between the quenched portions and the unquenched portions is small, no projection can be made by grinding. Therefore, the hardness of the quenched portions is desirably higher than that of the unquenched portions by HV100 or more.
A CO2 laser is suitable for the quenching process as its output is large.
The portions near the suction holes to be quenched may be any one of intermittent annular portions R2, R3 shown in
The portions near the discharge holes to be quenched may be any one of intermittent annular portions R2′, R3′ shown in
As shown in
As shown in
The annular quenched portions may be constituted of many quenched dots made by a sharply focused thin laser beam or a quenched belt made by an unsharply focused thick laser beam.
In
In the aforementioned embodiment, projections are formed on the end face of the valve plate 8 contacting the suction valve 10a and the end face of the valve plate 8 contacting the discharge valves 10b. The projections may be formed on either the end face of the valve plate 8 contacting the suction valve 10a or the end face of the valve plate 8 contacting the discharge valves 10b.
In the aforementioned embodiment, projections are formed on the valve plate 8. The projections shown in
Instead of quenching by laser beam machining and grinding to form projections, it is possible to form projections by any one of a resin coat, plated metal coat, such as plated nickel coat, plated chromium coat, plated iron coat, etc., thermal sprayed material coat, such as thermal sprayed metal coat, thermal sprayed ceramic coat, etc., sintered metal coat, such as sintered iron alloy coat, sintered copper alloy coat, etc., and ceramic coat, such as aluminum oxide coat, silicon oxide coat, etc. Productivity improves because forming projections by coating does not need machining so precise as forming projections by laser beam machining to melt and sputter.
A resin coat has an advantage in that it can be made easily. Among the various kinds of resin coats, fluoride resin coat repels oil to suppress generation of oil film. Therefore, fluoride resin coat is effective for preventing the suction valves 10a and/or the discharge valves 10b from sticking on the valve plate 8.
Desirably, binder resin such as polyamideimide, epoxy, polyimide, polyamide, polyether ether ketone, etc. is mixed with the fluoride resin so as to enhance the adherence between the fluoride resin coat and the base material.
Forming of the resin coat by screen printing is good in recovery of coating material.
Desirably, pre-coat surface treatment such as chemical conversion treating. Tufftride processing, shot blasting, etc. is carried out on the suction valves 10a, the discharge valves 10b or the valve plate 8 to enhance the adherence between the resin coat and the suction valves 10a, the discharge valves 10b or the valve plate 8.
A sintered metal coat has an advantage in that it is superior in wear resistance and peeling resistance. When the sintered metal coat is porous, it absorbs oil to suppress generation of oil film. Therefore, a porous sintered metal coat is effective for preventing the suction valves 10a and/or the discharge valves 10b from sticking on the valve plate 8. When a porous sintered metal coat is used for preventing the suction valves 10a and/or the discharge valves 10b from sticking on the valve plate 8, the porous sintered metal coat may cover the entire end surface of the valve plate 8 opposing the suction valves 10a and/or the discharge valves 10b.
When the porous sintered metal coat is impregnated with PTFE, i.e., polytetrafluoroethylene, it repels oil to suppress generation of oil film. Therefore, the porous sintered metal coat impregnated with PTFE is effective for preventing the suction valves 10a and/or discharge valves 10b from sticking on the valve plate 8.
The present invention can be widely used in various kinds of reciprocating compressors including swash plate compressors, wobble plate compressors, etc.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/JP2009/051902 | 2/4/2009 | WO | 00 | 8/4/2011 |