US20090180912A1 - Rotary compressor - Google Patents
Rotary compressor Download PDFInfo
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- US20090180912A1 US20090180912A1 US12/349,618 US34961809A US2009180912A1 US 20090180912 A1 US20090180912 A1 US 20090180912A1 US 34961809 A US34961809 A US 34961809A US 2009180912 A1 US2009180912 A1 US 2009180912A1
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- stage
- low
- cylinder
- discharge hole
- discharge
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
- F04C18/30—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members
- F04C18/34—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in group F04C18/08 or F04C18/22 and relative reciprocation between the co-operating members
- F04C18/356—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in group F04C18/08 or F04C18/22 and relative reciprocation between the co-operating members with vanes reciprocating with respect to the outer member
- F04C18/3562—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in group F04C18/08 or F04C18/22 and relative reciprocation between the co-operating members with vanes reciprocating with respect to the outer member the inner and outer member being in contact along one line or continuous surfaces substantially parallel to the axis of rotation
- F04C18/3564—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in group F04C18/08 or F04C18/22 and relative reciprocation between the co-operating members with vanes reciprocating with respect to the outer member the inner and outer member being in contact along one line or continuous surfaces substantially parallel to the axis of rotation the surfaces of the inner and outer member, forming the working space, being surfaces of revolution
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C23/00—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids
- F04C23/008—Hermetic pumps
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
- F04C29/12—Arrangements for admission or discharge of the working fluid, e.g. constructional features of the inlet or outlet
Definitions
- the present invention relates to a rotary compressor used in a refrigerating cycle of an air-conditioner.
- a rotary compressor configured so that a rotary compressor element and an electric element that drives the compressor element are pressed into and held in a cylindrical airtight container with an internal pressure of the container kept high. Furthermore, the rotary compressor is configured so that a discharge port (discharge hole) and a discharge valve opened or closed according to a magnitude of a discharge pressure are provided in each of an upper bearing (end plate) closing an upper opening of a cylindrical compression chamber of a cylinder and forming one bearing of a rotary shaft of the electric element and a lower bearing (end plate) closing a lower opening of the compression chamber and forming another bearing of the rotary shaft.
- the rotary compressor of this type is disclosed in, for example, Japanese Utility Model Application Laid-Open No. S56-175594.
- a two-stage rotary compressor configured so that two stages of rotary compressing sections are stacked and so that a compression target fluid is compressed by the low-stage compressing section and the high-stage compressing section by two stages. Furthermore, the two-stage rotary compressor is configured so that an inside diameter of a compression chamber of the low-stage compressing section is set larger than that of a compression chamber of the high-stage compressing section.
- a second discharge valve chamber (discharge hole) of the low-stage compressing section different from a first discharge valve chamber provided in a main bearing (end plate) is arranged at a position of a partition plate dividing a compressing section into the low-stage compressing section and the high-stage compressing section, which portion corresponds to an outer portion of the compression chamber of the low-stage compressing section.
- the compressor of this type is disclosed in, for example, Japanese Patent Application Laid-Open No. S63-272988.
- a compressor configured to include, in an airtight container, an electric element and a compressor element driven by the electric element and including a compression chamber that compresses a cooling medium containing lubricating oil.
- the compression chamber includes an introduction port for introducing the cooling medium containing the lubricating oil into the compression chamber, a first discharge port from which the compressed cooling medium is discharged, and a second discharge port from which the lubricating oil is discharged.
- a first discharge valve opened when a pressure of the compressed cooling medium reaches a first pressure in the compression chamber is provided in the first discharge port.
- a second discharge valve opened at a second pressure higher than the first pressure is provided in the second discharge port.
- An inverter-type rotary compressor has the following problems. Particularly during high-speed rotation, over-compression loss caused by a flow resistance of the cooling medium in the discharge port increases and the loss causes deterioration in efficiency of the rotary compressor. If a diameter of the discharge hole is increased to reduce the flow resistance, it is necessary to increase a thickness of the valve to ensure strength of the discharge port. If the valve is thicker, opening of the valve delays, resulting in the over-compression loss.
- the discharge ports are provided in both of the upper and lower bearings, respectively. Due to this, the structure of the compressing section is complicated, resulting in an increase in manufacturing cost of the rotary compressor. According to the technique disclosed in the Japanese Patent Application Laid-Open No. S63-272988, the discharge valve chambers (discharge holes) are provided in both the main baring and the partition plate, respectively. Similarly to the technique disclosed in Japanese Utility Model Application Laid-Open No. 56-175594, the structure of each of the compressing sections is complicated, resulting in an increase in manufacturing cost of the rotary compressor.
- a pressure of the front-stage (low-stage) compressing section is close to vacuum, the lubricating oil is impregnated into the front-stage compressing section from narrow gaps formed by components constituting a compression chamber of the front-side compressing section, and the compression chamber turns into a liquid compression state, thereby disadvantageously and greatly deteriorating efficiency of the compressor.
- the second discharge port is intended to discharge the lubricating oil from the compression chamber so as to prevent the deterioration in efficiency. Accordingly, during high-speed rotation of the compressor, the second discharge port is disadvantageously incapable of reducing the over-compression loss caused by the flow resistance of the cooling medium in the discharge port.
- a rotary compressor includes a compressing section.
- the compressing section includes a cylindrical cylinder; two end plates closing both ends of the cylinder, respectively; a piston held by an eccentric section of a rotary shaft driven to rotate by a motor, and revolving in the cylinder along a cylinder inner wall of the cylinder, a working chamber being formed between the piston and the cylinder inner wall; and a vane protruding from within a vane groove of the cylinder into the working chamber, abutting on the piston, and dividing the working chamber into a suction chamber and a compression chamber.
- the rotary compressor also includes an airtight compressor housing accommodating therein the compressing section; a suction hole provided in the cylinder and communicating the suction chamber with a low-pressure side of a refrigerating cycle; and a discharge hole provided in one of the end plates and communicating the compression chamber with a high-pressure side of the refrigerating cycle.
- an auxiliary discharge hole different from the discharge hole is provided in the one end plate.
- a rotary compressor includes a low-stage compressing section and a high-stage compressing section stacked on the low-stage compressing section via an intermediate partition plate.
- the low-stage compressing section includes a cylindrical low-stage cylinder; a low-stage end plate closing one end of the low-stage cylinder; a low-stage piston held by a low-stage eccentric section of a rotary shaft driven to rotate by a motor and revolving in the low-stage cylinder along a low-stage cylinder inner wall of the low-stage cylinder, a low-stage working chamber being formed between the low-stage piston and the low-stage cylinder inner wall; and a low-stage vane protruding from within a low-stage vane groove of the low-stage cylinder into the low-stage working chamber, abutting on the low-stage piston, and dividing the low-stage working chamber into a low-stage suction chamber and a low-stage compression chamber.
- the high-stage compressing section includes a cylindrical high-stage cylinder; a high-stage end plate closing one end of the high-stage cylinder; a high-stage piston held by a high-stage eccentric section of the rotary shaft driven to rotate by the motor and revolving in the high-stage cylinder along a high-stage cylinder inner wall of the high-stage cylinder, a high-stage working chamber being formed between the high-stage piston and the high-stage cylinder inner wall; and a high-stage vane protruding from within a high-stage vane groove of the high-stage cylinder into the high-stage working chamber, abutting on the high-stage piston, and dividing the high-stage working chamber into a high-stage suction chamber and a high-stage compression chamber.
- the rotary compressor also includes an airtight compressor housing accommodating therein the low-stage compressing section and the high-stage compressing section; a low-stage suction hole provided in the low-stage cylinder and communicating the low-stage suction chamber with a low-pressure side of a refrigerating cycle; a low-stage discharge hole provided in the low-stage end plate and communicating the low-stage compression chamber with a high-stage suction hole provided in the high-stage cylinder; and a high-stage discharge hole provided in the high-stage end plate and communicating the high-stage compression chamber with a high-pressure side of the refrigerating cycle.
- a low-stage auxiliary discharge hole different from the low-stage discharge hole is provided in the low-stage end plate.
- FIG. 1 is a longitudinal sectional view of a rotary compressor according to a first embodiment of the present invention
- FIG. 2 is a top view of a compressing section of the rotary compressor shown in FIG. 1 ;
- FIG. 3 is a perspective view of an upper surface of the compressing section closed by one of end plates;
- FIG. 4 is a chart showing the relationship between a revolution angle of a piston and a discharge pressure
- FIG. 5 is a chart showing the relationship between the revolution angle of the piston and a change of a volume of a compression chamber
- FIG. 6 is a chart showing the relationship between the revolution angle of the piston and a change rate of the volume of the compression chamber
- FIG. 7 is a longitudinal sectional view of a rotary compressor according to a second embodiment of the present invention.
- FIG. 8 is a bottom view of a low-stage compressing section of the rotary compressor shown in FIG. 7 ;
- FIG. 9 is a cross-sectional view of a high-stage compressing section of the rotary compressor shown in FIG. 7 ;
- FIG. 10 is a perspective view of a lower surface of the low-stage compressing section closed by a low-stage end plate
- FIG. 11 is a chart showing the relationship between a revolution angle of a piston and a discharge pressure of the low-stage compressing section
- FIG. 12 is a bottom view of a low-stage compressing section of a rotary compressor according to a modification of the second embodiment
- FIG. 13 is a perspective view of a lower surface of the low-stage compressing section closed by a low-stage end plate according to the modification of the second embodiment
- FIG. 14 is a longitudinal sectional view of a rotary compressor according to a third embodiment of the present invention.
- FIG. 15 is a cross-sectional view of first and second compressing sections of the rotary compressor shown in FIG. 14 ;
- FIG. 16 is a top view of a compressing section of a rotary compressor according to a fourth embodiment of the present invention.
- FIG. 17 is a top view of the compressing section of the rotary compressor according to the first embodiment for reference.
- FIG. 1 is a longitudinal sectional view of a rotary compressor according to a first embodiment of the present invention.
- FIG. 2 is a top view of a compressing section of the rotary compressor shown in FIG. 1 .
- FIG. 3 is a perspective view of an upper surface of the compressing section closed by one of end plates.
- FIG. 4 is a chart showing the relationship between a revolution angle of a piston and a pressure of a compression chamber.
- FIG. 5 is a chart showing the relationship between the revolution angle of the piston and a volume of the compression chamber.
- FIG. 6 is a chart showing the relationship between the revolution angle of the piston and a change rate of the volume of the compression chamber.
- a rotary compressor 1 includes, in an airtight cylindrical compressor housing 10 , a compressing section 12 , and a motor 11 driving the compressing section 12 .
- a stator 111 of the motor 11 is fixedly shrunk to an inner circumferential surface of the compressor housing 10 .
- a rotor 112 of the motor 11 is arranged in a central portion of the stator 111 and fixedly shrunk to a rotary shaft 15 mechanically connecting the motor 11 to the compressing section 12 .
- the compressing section 12 includes a short cylindrical cylinder 121 .
- a cylindrical cylinder inner wall 123 is formed on the cylinder 121 to be concentric with the motor 11 .
- a cylindrical piston 125 having an outside diameter smaller than a diameter of the cylinder inner wall 123 is arranged in the cylinder inner wall 123 , and a working chamber 130 (compression space) sucking in, compressing, and discharging a cooling medium is formed between the cylinder inner wall 123 and the piston 125 .
- a vane groove 128 is formed in the cylinder 121 in a range of an entire length of the cylinder 121 from the cylinder inner wall 123 in a radial direction of the cylinder 121 .
- a flat vane 127 is fitted into the vane groove 128 .
- a spring is arranged in an inner part of the vane groove 128 . In a normal state, the vane 127 protrudes from within the vane groove 128 into the working chamber 130 by a repulsive force of the spring, a tip end of the vane 127 abuts on an outer circumferential surface of the piston 125 , and the vane 127 divides the working chamber 130 (compression space) into a suction chamber 131 and a compression chamber 133 .
- a backpressure introduction path 129 communicating the inner part of the vane groove 128 with an interior of the compressor housing 10 and applying a backpressure to the vane 127 is formed on the cylinder 121 .
- a suction hole 135 communicating with the suction chamber 131 is provided in the cylinder 121 to suck the cooling medium into the suction chamber 131 .
- one end plate 160 A is disposed on an upper end of the cylinder 121 and closes an upper portion of the working chamber 130 of the cylinder 121 .
- the other end plate 160 B is disposed on a lower end of the cylinder 121 and closes a lower portion of the working chamber 130 .
- a sub bearing 161 B is formed on the other end plate 160 B and a sub bearing support 151 of the rotary shaft 15 is rotatably supported by the sub bearing 161 B.
- a main bearing 161 A is formed on one end plate 160 A and a main bearing support 153 of the rotary shaft 15 is rotatably supported by the main bearing 161 A.
- the rotary shaft 15 includes an eccentric section 152 and the eccentric section 152 rotatably holds the piston 125 of the compressing section 12 .
- the piston 125 revolves clockwise in the cylinder 121 along the cylinder inner wall 123 in FIGS. 2 and 3 and the vane 127 follows to reciprocate. Volumes of the suction chamber 131 and the compression chamber 133 continuously change by movements of the piston 125 and the vane 127 , and the compressing section 121 continuously sucks in, compresses, and discharges the cooling medium.
- a muffler cover 170 is disposed above one end plate 160 A and a muffler chamber 180 is formed between the muffler cover 170 and the end plate 160 A.
- a discharge portion of the compressing section 12 communicates with the interior of the compressor housing 10 via the muffler chamber 180 .
- a discharge hole 190 communicating the compression chamber 133 of the cylinder 121 with the muffler chamber 180 is provided in one end plate 160 A near the vane 127 and a discharge valve 200 preventing backflow of the compressed cooling medium is provided in the discharge hole 190 .
- a discharge valve holding member 201 as well as the discharge valve 200 is fixed to the end plate 160 A by a rivet so as to restrict a deflection opening amount of the discharge valve 200 .
- the muffler chamber 180 reduces pressure pulsation of the discharged cooling medium.
- the other end plate 160 B, the cylinder 121 , one end plate 160 A, and the muffler cover 170 are integrally fastened by a bolt that is not shown.
- an outer peripheral portion of one end plate 160 A is fixedly bonded to the compressor housing 10 by spot welding to thereby fix the compressing section 12 to the compressor housing 10 .
- a through hole 101 is provided in an outer circumferential wall of the cylindrical compressor housing 10 .
- An accumulator 25 formed of an independent and cylindrical airtight container is arranged outside of the compressor housing 10 and held by an accumulator holder 251 and an accumulator band 253 .
- a system connecting pipe 255 connecting the accumulator 25 to a low-pressure side of a refrigerating cycle is provided in a central portion of a top surface of the accumulator 25 .
- a low-pressure connecting pipe 31 having one end extending toward an upper portion of an interior of the accumulator 25 and the other end connected to the other end of a suction pipe 104 is connected to a bottom through hole 257 provided at a bottom of the accumulator 25 .
- the low-pressure connecting pipe 31 introducing a low-pressure cooling medium of the refrigerating cycle to the compressing section 12 via the accumulator 25 is connected to the suction hole 135 (see FIG. 2 ) via the through hole 101 and the suction pipe 104 . Accordingly, the suction hole 135 communicates with the low-pressure side of the refrigerating cycle.
- a discharge pipe 107 connected to a high-pressure side of the refrigerating cycle and discharging a high pressure cooling medium toward the high-pressure side of the refrigerating cycle is connected to a top of the compressor housing 10 . Accordingly, the discharge hole 190 communicates with the high-pressure side of the refrigerating cycle.
- the compressor housing 10 is filled with lubricating oil almost up to a height of the cylinder 121 .
- the lubricating oil circulates in the compressing section 12 by a vane pump, not shown, attached to a lower portion of the rotary shaft 15 and seals a portion defining the working chamber 130 (compression space) for the compressed cooling medium by lubrication of sliding components and narrow gaps.
- the rotary compressor 1 is characteristically configured so that an auxiliary discharge hole 190 A communicating the compression chamber 133 with the high-pressure side of the refrigerating cycle is provided in one end plate 160 A in which the discharge hole 190 is provided.
- the discharge valve 200 and the discharge valve holding member 201 are disposed in the auxiliary discharge hole 190 A similarly to the discharge hole 190 .
- a discharge groove 124 communicating with the discharge hole 190 is provided in a region of the cylinder inner wall 123 corresponding to a position of the discharge hole 190 provided in one end plate 160 A.
- a discharge groove 124 A communicating with the auxiliary discharge hole 190 A is provided in a region of the cylinder inner wall 123 corresponding to a position of the auxiliary discharge hole 190 A. The discharge grooves 124 and 124 A reduce the flow resistance of the cooling medium discharged from the compression chamber 133 into the discharge hole 190 and the auxiliary discharge hole 190 A.
- the auxiliary discharge hole 190 A is provided at a position away from the vane groove 128 by 230° to 300° in a direction of revolution of the piston 125 along the cylinder inner wall 123 .
- the reason is as follows.
- concave portions 190 K and 190 AK are provided in the end plate 160 A separately to accommodate the discharge valves 200 and the discharge valve holding members 201 (see FIG. 1 ) preventing backflow of the cooling medium in the discharge hole 190 and the auxiliary discharge hole 190 A, respectively. If the concave portions 190 K and 190 AK interfere with each other, a rib 190 R wears away and strength of the end plate 160 A weakens. To prevent this, the auxiliary discharge hole 190 A is provided at the position within 300° from the vane groove 128 in the direction of revolution of the piston 125 along the cylinder inner wall 123 .
- the rotary compressor 1 has a high change rate of a volume of the compression chamber 133 , that is, a high discharge flow speed when the piston 125 revolves by 135° to 225° from the position of the vane groove 128 .
- a flow speed of the discharged cooling medium is the highest and pressure loss is the greatest.
- the auxiliary discharge hole 190 A is communicable without being cut off by end surfaces of the compression chamber 133 and the piston 125 right after the discharge valve 200 opens by 210°, the auxiliary discharge hole 190 A operates effectively. Due to this, the auxiliary discharge hole 190 A is provided at the position away from the vane groove 128 at least by 230° in the direction of the revolution of the piston 125 along the cylinder inner wall 123 .
- the position of the auxiliary discharge hole 190 A is not limited to the above-stated position.
- the rib 190 R may not be provided and the auxiliary discharge hole 190 A may be provided at a position away from the vane groove 128 by 300° or more.
- the rotary compressor 1 If the rotary compressor 1 is actuated, the cooling medium flowing from the low-pressure side of the refrigerating cycle into the accumulator 25 through the system connecting pipe 255 is separated into a liquid cooling medium and a gas cooling medium. Specifically, the liquid cooling medium is accumulated in a lower portion of the accumulator 25 and the gas cooling medium is accumulated in an upper portion thereof.
- the pressure of the compressed cooling medium in the compression chamber 133 becomes equal to a pressure of the muffler chamber 180 located downstream of the discharge valves 200 provided in the discharge hole 190 and the auxiliary discharge hole 190 A, respectively, that is, discharge pressure, then the discharge valves 200 open, and the cooling medium is discharged into the muffler chamber 180 through the discharge hole 190 and the auxiliary discharge hole 190 A at low flow resistance and the pressure pulsation causing noise is reduced in the muffler chamber 180 .
- the cooling medium is discharged, as a high-pressure cooling medium, into the compressor housing 10 .
- the high-pressure cooling medium is fed to an upper portion of the motor 11 through a core notch, not shown, of the stator 111 of the motor 11 and a gap between a core and a coil, and discharged toward the high-pressure side of the refrigerating cycle through the discharge pipe 107 .
- the cooling medium is discharged into the muffler chamber 180 through the discharge hole 190 and the auxiliary discharge hole 190 A at the low flow resistance. Therefore, the over-compression loss can be reduced. Further, there is no need to work the concave portion 190 K accommodating therein the discharge hole 190 , the valve seat around the discharge hole 190 , and the discharge valve 200 to be provided on each of the end plates 160 A and 160 B. Therefore, working cost can be reduced.
- FIG. 7 is a longitudinal sectional view of a rotary compressor according to a second embodiment of the present invention.
- FIG. 8 is a bottom view of a low-stage compressing section of the rotary compressor shown in FIG. 7 .
- FIG. 9 is a cross-sectional view of a high-stage compressing section of the rotary compressor shown in FIG. 7 .
- FIG. 10 is a perspective view of a lower surface of the low-stage compressing section closed by a low-stage end plate.
- FIG. 11 is a chart showing the relationship between a revolution angle of a piston and a discharge pressure of the low-stage compressing section.
- FIG. 12 is a bottom view of a low-stage compressing section of a rotary compressor according to a modification of the second embodiment.
- FIG. 13 is a perspective view of a lower surface of the low-stage compressing section closed by a low-stage end plate according to the modification of the second embodiment.
- a rotary compressor 2 includes, in an airtight cylindrical compressor housing 10 , a compressing section 12 and a motor 11 driving the compressing section 12 .
- a stator 111 of the motor 11 is fixedly shrunk to an inner circumferential surface of the compressor housing 10 .
- a rotor 112 of the motor 11 is arranged in a central portion of the stator 111 and fixedly shrunk to a rotary shaft 15 mechanically connecting the motor 11 to the compressing section 12 .
- the compressing section 12 includes a low-stage compressing section 12 L and a high-stage compressing section 12 H connected in series to the low-stage compressing section 12 L and disposed to be stacked on an upper side of the low-stage compressing section 12 L.
- the low-stage compressing section 12 L includes a short cylindrical cylinder 121 L.
- the high-stage compressing section 12 H includes a short cylindrical cylinder 121 H.
- Cylindrical low-stage and high-stage cylinder inner walls 123 L and 123 H are formed on the low-stage cylinder 121 L and the high-stage cylinder 121 H to be concentric with the motor 11 , respectively.
- Cylindrical low-stage and high-stage pistons 125 L and 125 H having outside diameters smaller than diameters of the low-stage and high-stage cylinder inner walls 123 L and 123 H are arranged in the low-stage and high-stage cylinder inner walls 123 L and 123 H, respectively.
- low-stage and high-stage working chambers 130 L and 130 H compression spaces absorbing, compressing, and discharging a cooling medium are formed between the low-stage and high-stage cylinder inner walls 123 L and 123 H and the low-stage and high-stage pistons 125 L and 124 H, respectively.
- Low-stage and high-stage vane grooves 128 L and 128 H are formed in the low-stage and high-stage cylinders 121 L and 121 H in a range of entire lengths of the low-stage and high-stage cylinders 121 L and 121 H from the low-stage and high-stage cylinder inner walls 123 L and 123 H in a radial direction of the low-stage and high-stage cylinders 121 L and 121 H, respectively.
- Low-stage and high-stage flat vanes 127 L and 127 H are fitted into the low-stage and high-stage vane grooves 128 L and 128 H, respectively.
- the high-stage cylinder 121 H, the high-stage piston 125 H, and the high-stage vane 127 H are set lower in axial height than the low-stage cylinder 121 L, the low-stage piston 125 L, and the low-stage vane 127 L, respectively.
- Low-stage and high-stage springs are arranged in inner parts of the low-stage and high-stage vane grooves 128 L and 128 H, respectively.
- the low-stage and high-stage vanes 127 L and 127 H protrude from within the low-stage and high-stage vane grooves 128 L and 128 H into the low-stage and high-stage working chambers 130 L and 130 H by repulsive forces of the low-stage and high-stage springs, respectively.
- Tip end of the low-stage and high-stage vanes 127 L and 127 H abut on outer circumferential surfaces of the low-stage and high-stage pistons 125 L and 125 H, and the low-stage and high-stage vanes 127 L and 127 H divide the low-stage and high-stage working chambers 130 L and 130 H (compression spaces) into low-stage and high-stage suction chambers 131 L and 131 H and low-stage and high-stage compression chambers 133 L and 133 H, respectively.
- Low-stage and high-stage backpressure introduction paths 129 L and 129 H communicating the inner parts of the low-stage and high-stage vane grooves 128 L and 128 H with an interior of the compressor housing 10 and applying a backpressure to the low-stage and high-stage vanes 127 L and 127 H are formed on the low-stage and high-stage cylinders 121 L and 121 H, respectively.
- Low-stage and high-stage suction holes 135 L and 135 H communicating with the low-stage and high-stage suction chambers 131 L and 131 H are provided in the low-stage and high-stage cylinders 121 L and 121 H to absorb the cooling medium into the low-stage and high-stage suction chambers 131 L and 131 H, respectively.
- an intermediate partition plate 140 is provided between the low-stage cylinder 121 L and the high-stage cylinder 121 H to divide a working chamber into the low-stage working chamber 130 L of the low-stage cylinder 121 L and the high-stage working chamber 130 H of the high-stage cylinder 121 H.
- a low-stage end plate 160 L is disposed on a lower end of the low-stage cylinder 121 L and closes the low-stage working chamber 130 L of the low-stage cylinder 121 L.
- a high-stage end plate 160 H is disposed on an upper end of the high-stage cylinder 121 H and closes the high-stage working chamber 130 H of the high-stage cylinder 121 H.
- a sub bearing 161 L is formed on the low-stage end plate 160 L and a sub bearing support 151 of the rotary shaft 15 is rotatably supported by the sub bearing 161 L.
- a main bearing 161 H is formed on the high-stage end plate 160 H and a main bearing support 153 of the rotary shaft 15 is rotatably supported by the main bearing 161 H.
- the rotary shaft 15 includes low-stage and high-stage eccentric sections 152 L and 152 H eccentric to be shifted in phase by 180° from each other.
- the low-stage eccentric section 152 L rotatably holds the low-stage piston 125 L of the low-stage compressing section 12 L.
- the high-stage eccentric section 152 H rotatably holds the high-stage piston 125 H of the high-stage compressing section 12 H.
- the low-stage and high-stage pistons 125 L and 125 H revolve clockwise in the low-stage and high-stage cylinders 121 L and 121 H along the low-stage and high-stage cylinder inner walls 123 L and 123 H in FIG. 8 (revolve counterclockwise in FIG. 9 ), and the low-stage and high-stage vanes 127 L and 127 H follow to reciprocate.
- volumes of the low-stage and high-stage suction chambers 131 L and 131 H and the low-stage and high-stage compression chambers 133 L and 133 H continuously change by movements of the low-stage and high-stage pistons 125 L and 125 H and the low-stage and high-stage vanes 127 L and 127 H, respectively, and the compressing section 12 continuously absorbs, compresses, and discharges the cooling medium.
- a low-stage muffler cover 170 L is disposed below the low-stage end plate 160 L and a low-stage muffler chamber 180 L is formed between the low-stage muffler cover 170 L and the low-stage end plate 160 L.
- a discharge portion of the low-stage compressing section 12 L opens to the low-stage muffler chamber 180 L.
- a low-stage discharge hole 190 L communicating the low-stage compression chamber 133 L of the low-stage cylinder 121 L with the low-stage muffler chamber 180 L is provided in the low-stage end plate 160 L near the low-stage vane 127 L and a low-stage discharge valve 200 L preventing backflow of the compressed cooling medium is provided in the low-stage discharge hole 190 L.
- the low-stage muffler chamber 180 L is one annularly communicable chamber and a part of an intermediate communicating path communicating a discharge side of the low-stage compressing section 12 L with a suction side of the high-stage compressing section 12 H.
- the low-stage muffler chamber 180 L reduces pressure pulsation of the discharged cooling medium.
- a low-stage discharge valve holding member 201 L as well as the low-stage discharge valve 200 L is fixed to the low-stage end plate 160 L by a rivet so as to restrict a deflection opening amount of the low-stage discharge valve 200 L.
- a low-stage muffler discharge hole 210 L discharging the cooling medium in the low-stage muffler chamber 180 L to outside is provided in an outer peripheral wall of the low-stage end plate 160 L.
- the low-stage muffler discharge hole 210 L is provided radially at a position in a circumferential direction of the compressor housing 10 and different in phase from the low-stage and high-stage suction holes 135 L and 135 H of the compressing section 12 .
- a high-stage muffler cover 170 H is disposed above the high-stage end plate 160 H and a high-stage muffler chamber 180 H is formed between the high-stage muffler cover 170 H and the high-stage end plate 160 H.
- a high-stage discharge hole 190 H communicating the high-stage compression chamber 133 H of the high-stage cylinder 121 H with the high-stage muffler chamber 180 H is provided in the high-stage end plate 160 H near the high-stage vane 127 H and a high-stage discharge valve 200 H preventing backflow of the compressed cooling medium is provided in the high-stage discharge hole 190 H.
- a high-stage discharge valve holding member 201 H as well as the high-stage discharge valve 200 H is fixed to the high-stage end plate 160 H by a rivet so as to restrict a deflection opening amount of the high-stage discharge valve 200 H.
- the high-stage muffler chamber 180 H reduces pressure pulsation of the discharged cooling medium.
- the low-stage cylinder 121 L, the low-stage end plate 160 L, the low-stage muffler cover 170 L, the high-stage cylinder 121 H, the high-stage end plate 160 H, the high-stage muffler cover 170 H, and the intermediate partition plate 140 are integrally fastened by a bolt that is not shown.
- an outer peripheral portion of the high-stage end plate 160 H is fixedly bonded to the compressor housing 10 by spot welding to thereby fix the compressing section 12 to the compressor housing 10 .
- first, second, and third through holes 101 , 102 , and 103 are provided in an outer circumferential wall of the cylindrical compressor housing 10 to be axially away from one another in ascending order from a lower portion.
- An accumulator 25 formed of an independent and cylindrical airtight container is arranged outside of the compressor housing 10 and held by an accumulator holder 251 and an accumulator band 253 .
- a system connecting pipe 255 connecting the accumulator 25 to a low-pressure side of a refrigerating cycle is provided in a central portion of a top surface of the accumulator 25 .
- a low-pressure connecting pipe 31 having one end extending toward an upper portion of an interior of the accumulator 25 and the other end connected to the other end of a suction pipe 104 is connected to a bottom through hole 257 provided at a bottom of the accumulator 25 .
- the low-pressure connecting pipe 31 introducing a low-pressure cooling medium of the refrigerating cycle to the compressing section 12 via the accumulator 25 is connected to the low-stage suction hole 135 L of the low-stage cylinder 121 L via the second through hole 102 and the low-stage suction pipe 104 . Accordingly, the low-stage suction hole 135 L communicates with the low-pressure side of the refrigerating cycle.
- One end of the low-stage discharge pipe 105 is connected to the low-stage muffler discharge hole 210 L of the low-stage muffler chamber 180 L through the first through hole 101 .
- One end of the high-stage discharge suction pipe 106 is connected to the high-stage suction hole 135 H of the high-stage cylinder 121 H through the third through hole 103 .
- the other end of the low-stage discharge pipe 105 is connected to the other end of the high-stage suction pipe 106 by an intermediate connecting pipe 23 .
- a low-pressure connecting pipe 31 and the intermediate connecting pipe 23 are formed so as not to interfere with each other.
- a discharge portion of the high-stage compressing section 12 H communicates with the interior of the compressor housing 10 via the high-stage muffler chamber 180 H.
- the high-stage discharge hole 190 H communicating the high-stage compression chamber 133 H of the high-stage cylinder 121 H with the high-stage muffler chamber 180 H is provided in the high-stage end plate 160 H, and the high-stage discharge valve 200 H preventing backflow of the compressed cooling medium is disposed in the high-stage discharge hole 190 H.
- a discharge pipe 107 connected to a high-pressure side of the refrigerating cycle and discharging the high-pressure cooling medium toward the high-pressure side of the refrigerating cycle is connected to a top of the compressor housing 10 . Accordingly, the high-stage discharge hole 190 H communicates with the high-pressure side of the refrigerating cycle.
- the compressor housing 10 is filled with lubricating oil almost up to a height of the high-stage cylinder 121 H.
- the lubricating oil circulates in the compressing section 12 by a vane pump, not shown, attached to a lower portion of the rotary shaft 15 and seals a portion defining the low-stage and high-stage working chambers 130 L and 130 H (compression spaces) for the compressed cooling medium by lubrication of sliding components and narrow gaps.
- the rotary compressor 2 is characteristically configured so that a low-stage auxiliary discharge hole 190 LL communicating the low-stage compression chamber 133 L with the high-stage compressing section 12 H is provided in the low-stage end plate 160 L in which the low-stage discharge hole 190 L is provided.
- a low-stage discharge valve 200 L is disposed in the low-stage auxiliary discharge hole 190 LL similarly to the low-stage discharge hole 190 L.
- a discharge groove 124 L communicating with the low-stage discharge hole 190 L is provided in a region of the low-stage cylinder inner wall 123 L corresponding to a position of the low-stage discharge hole 190 L provided in the low-stage end plate 160 L.
- a discharge groove 124 LA communicating with the low-stage auxiliary discharge hole 190 LL is provided in a region of the low-stage cylinder inner wall 123 L corresponding to a position of the low-stage auxiliary discharge hole 190 LL.
- the discharge grooves 124 L and 124 LA reduce the flow resistance of the cooling medium discharged from the low-stage compression chamber 133 L into the low-stage discharge hole 190 L and the low-stage auxiliary discharge hole 190 LL.
- the low-stage auxiliary discharge hole 190 LL is provided at a position away from the low-stage vane groove 128 L by 190° to 300° in a direction of revolution of the low-stage piston 125 L along the low-stage cylinder inner wall 123 L.
- the reason for providing the low-stage auxiliary discharge hole 190 LL at the position within 300° is the same as that described in the first embodiment.
- the rotary compressor 2 has a high change rate of a volume of the low-stage compression chamber 133 L, that is, a high discharge flow speed when the low-stage piston 125 L revolves by 135° to 225° from the position of the low-stage vane groove 128 L. Accordingly, right after the low-stage discharge valve 200 L opens by 170°, a flow speed of the discharged cooling medium is the highest and pressure loss is the greatest.
- the low-stage auxiliary discharge hole 190 LL is communicable without being cut off by end surfaces of the low-stage compression chamber 133 L and the low-stage piston 125 L right after the low-stage discharge valve 200 opens by 170°, the low-stage auxiliary discharge hole 190 LL operates effectively. Due to this, the low-stage auxiliary discharge hole 190 LL is provided at the position away from the low-stage vane groove 128 L at least by 190° in the direction of the revolution of the low-stage piston 125 L along the low-stage cylinder inner wall 123 L.
- the cooling medium flowing from the low-pressure side of the refrigerating cycle into the accumulator 25 through the system connecting pipe 255 is separated into a liquid cooling medium and a gas cooling medium.
- the liquid cooling medium is accumulated in a lower portion of the accumulator 25 and the gas cooling medium is accumulated in an upper portion thereof.
- the gas cooling medium in the accumulator 25 is absorbed into the low-stage suction chamber 131 L of the low-stage compressing section 12 L through the low-pressure connecting pipe 31 , the low-stage suction pipe 104 L, and the low-stage suction hole 135 .
- the low-stage piston 125 L revolves once, the low-stage suction chamber 131 L is cut off from the low-stage suction hole 135 L and changed over to the low-stage compression chamber 133 L, and the cooling medium is compressed in the low-stage compression chamber 133 L.
- the pressure of the compressed cooling medium in the low-stage compression chamber 133 L becomes equal to the pressure of the low-stage muffler chamber 180 L located downstream of the low-stage discharge valves 200 L provided in the low-stage discharge hole 190 L and the low-stage auxiliary discharge hole 190 LL, respectively, that is, the intermediate pressure (low-stage discharge pressure), then the low-stage discharge valves 200 L open, and the cooling medium is discharged into the low-stage muffler chamber 180 L through the low-stage discharge hole 190 L and the low-stage auxiliary discharge hole 190 LL at low flow resistance and the pressure pulsation causing noise is reduced in the low-stage muffler chamber 180 L. Thereafter, the cooling medium is fed to the high-stage suction chamber 131 H of the high-stage compressing section 12 H through the low-stage discharge pipe 105 , the intermediate connecting pipe 23 , and the high-stage suction hole 135 H.
- the cooling medium fed to the high-stage suction chamber 131 H of the high-stage compressing section 12 H is compressed and discharged by similar operation to that of the low-stage compressing section 12 L and the pressure pulsation is reduced in the high-stage muffler chamber 180 H. Thereafter, the cooling medium is discharged, as a high-pressure cooling medium, into the compressor housing 10 . Thereafter, the high-pressure cooling medium is fed to an upper portion of the motor 11 through a core notch, not shown, of the stator 111 of the motor 11 and a gap between a core and a coil, and discharged toward the high-pressure side of the refrigerating cycle through the discharge pipe 107 .
- the cooling medium is discharged into the low-stage muffler chamber 180 L through the low-stage discharge hole 190 L and the low-stage auxiliary discharge hole 190 LL at the low flow resistance. Therefore, the over-compression loss can be reduced. Further, manufacturing cost can be reduced as compared with of the case in which the low-stage auxiliary discharge hole is provided in the intermediate partition plate 140 .
- the pressure ratio is shared between the two compression chambers and the low-stage pressure ratio is generally, therefore, as low as 1.5 to 2.0. Accordingly, since the cooling medium is discharged from the compression chambers in a state in which a volume of the cooling medium is large, it is effective to provide the auxiliary discharge hole particularly for reduction of the over-compression loss (flow resistance).
- FIG. 12 is a bottom view of a low-stage compressing section according to a modification of the second embodiment.
- FIG. 13 is a perspective view of a lower surface of the low-stage compressing section closed by a low-stage end plate according to the modification of the second embodiment.
- concave portions 190 K and 190 AK provided in the low-stage end plate 160 L are caused to interfere with each other, a rib 190 R is removed, a fixed portion 190 S common to integrated L-shaped lower-stage discharge valve and lower-stage discharge valve holding member is provided, thereby providing an L-shaped concave portion.
- the L-shaped concave portion accommodates therein the integrated L-shaped lower-stage discharge valve and lower-stage discharge valve holding member for preventing backflow in the low-stage discharge hole 190 L and the low-stage auxiliary discharge hole 190 LL.
- the low-stage end plate 160 L has sufficient strength by providing different concave portions near the low-stage discharge hole 190 L and the low-stage auxiliary discharge hole 190 LL, respectively. It is also possible to integrate the low-stage discharge valve with the low-stage discharge valve holding member by making only the fixed portion 190 S common to the low-stage discharge valve and the low-stage discharge valve holding member. Cost can be thereby reduced.
- FIG. 14 is a longitudinal sectional view of a rotary compressor according to a third embodiment of the present invention.
- FIG. 15 is a cross-sectional view of a second compressing section of the rotary compressor shown in FIG. 14 .
- a rotary compressor 3 includes, in an airtight cylindrical compressor housing 10 , a compressing section 12 and a motor 11 driving the compressing section 12 .
- a stator 111 of the motor 11 is fixedly shrunk to an inner circumferential surface of the compressor housing 10 .
- a rotor 112 of the motor 11 is arranged in a central portion of the stator 111 and fixedly shrunk to a rotary shaft 15 mechanically connecting the motor 11 to the compressing section 12 .
- the compressing section 12 includes a first compressing section 12 S and a second compressing section 12 T connected in parallel to the first compressing section 12 S and disposed to be stacked on an upper side of the first compressing section 12 S.
- the first and second compressing sections 12 S and 12 T include short cylindrical cylinders 121 S and 121 T, respectively.
- first and second cylinder inner walls 123 S and 123 T are formed on the first cylinder 121 S and the second cylinder 121 T to be concentric with the motor 11 , respectively.
- Cylindrical first and second pistons 125 S and 125 T having outside diameters smaller than diameters of the first and second cylinder inner walls 123 S and 123 T are arranged in the first and second cylinder inner walls 123 S and 123 T, respectively.
- first and second working chambers 130 S and 130 T compression spaces
- absorbing, compressing, and discharging a cooling medium are formed between the first and second cylinder inner walls 123 S and 123 T and the first and second pistons 125 S and 124 T, respectively.
- First and second vane grooves 128 S and 128 T are formed in the first and second cylinders 121 S and 121 T in a range of entire lengths of the first and second cylinders 121 S and 121 T from the first and second cylinder inner walls 123 S and 123 T in a radial direction of the first and second cylinders 121 S and 121 T, respectively.
- First and second flat vanes 127 S and 127 T are fitted into the first and second vane grooves 128 S and 128 T, respectively.
- the second cylinder 121 T, the second piston 125 T, and the second vane 127 T are set lower in axial height than the first cylinder 121 S, the first piston 125 S, and the first vane 127 S, respectively.
- First and second springs are arranged in inner parts of the first and second vane grooves 128 S and 128 T, respectively.
- the first and second vanes 127 S and 127 T protrude from within the first and second vane grooves 128 S and 128 T into the first and second working chambers 130 S and 130 T by repulsive forces of the first and second springs, respectively.
- first and second vanes 127 S and 127 T abut on outer circumferential surfaces of the first and second pistons 125 S and 125 T, and the first and second vanes 127 S and 127 T divide the first and second working chambers 130 S and 130 T (compression spaces) into first and second suction chambers 131 S and 131 T and first and second compression chambers 133 S and 133 T, respectively.
- First and second backpressure introduction paths 129 S and 129 T communicating the inner parts of the first and second vane grooves 128 S and 128 T with an interior of the compressor housing 10 and applying a backpressure to the first and second vanes 127 S and 127 T are formed on the first and second cylinders 121 S and 121 T, respectively.
- First and second suction holes 135 S and 135 T communicating with the first and second suction chambers 131 S and 131 T are provided in the first and second cylinders 121 S and 121 T to absorb the cooling medium into the first and second suction chambers 131 S and 131 T, respectively.
- an intermediate partition plate 140 is provided between the first cylinder 121 S and the second cylinder 121 T to divide a working chamber into the first working chamber 130 S of the first cylinder 121 S and the second working chamber 130 T of the second cylinder 121 T.
- a first end plate 160 S is disposed on a lower end of the first cylinder 121 S and closes the first working chamber 130 S of the first cylinder 121 S.
- a second end plate 160 T is disposed on an upper end of the second cylinder 121 T and closes the second working chamber 130 T of the second cylinder 121 T.
- a sub bearing 161 S is formed on the first end plate 160 S and a sub bearing support 151 of the rotary shaft 15 is rotatably supported by the sub bearing 161 S.
- a main bearing 161 T is formed on the second end plate 160 T and a main bearing support 153 of the rotary shaft 15 is rotatably supported by the main bearing 161 T.
- the rotary shaft 15 includes first and second eccentric sections 152 S and 152 T eccentric to be shifted in phase by 180° from each other.
- the first eccentric section 152 S rotatably holds the first piston 125 S of the first compressing section 12 S.
- the second eccentric section 152 T rotatably holds the second piston 125 T of the second compressing section 12 T.
- the first and second pistons 125 S and 125 T revolve clockwise in the first and second cylinders 121 S and 121 T along the first and second cylinder inner walls 123 S and 123 T, and the first and second vanes 127 S and 127 T follow to reciprocate.
- Volumes of the first and second suction chambers 131 S and 131 T and the first and second compression chambers 133 S and 133 T continuously change by movements of the first and second pistons 125 S and 125 T and the first and second vanes 127 S and 127 T, respectively, and the compressing section 12 continuously absorbs, compresses, and discharges the cooling medium.
- a first muffler cover 170 S is disposed below the first end plate 160 S and a first muffler chamber 180 S is formed between the first muffler cover 170 S and the first end plate 160 S.
- a discharge portion of the first compressing section 12 S opens to the first muffler chamber 180 S.
- a first discharge hole 190 S communicating the first compression chamber 133 S of the first cylinder 121 S with the first muffler chamber 180 S is provided in the first end plate 160 S near the first vane 127 S and a first discharge valve 200 S preventing backflow of the compressed cooling medium is provided in the first discharge hole 190 S.
- the first muffler chamber 180 S is one annularly communicable chamber and a part of an intermediate communicating path communicating a discharge side of the first compressing section 12 S with the interior of the compressor housing 10 .
- the first muffler chamber 180 S reduces pressure pulsation of the discharged cooling medium.
- a first discharge valve holding member 201 S as well as the first discharge valve 200 S is fixed on the first discharge valve 200 S by a rivet so as to restrict a deflection opening amount of the first discharge valve 200 S.
- a second muffler cover 170 T is disposed above the second end plate 160 T and a second muffler chamber 180 T is formed between the second muffler cover 170 T and the second end plate 160 T.
- a second discharge hole 190 T communicating the second compression chamber 133 T of the second cylinder 121 T with the second muffler chamber 180 T is provided in the second end plate 160 T near the second vane 127 T and a second discharge valve 200 T preventing backflow of the compressed cooling medium is provided in the second discharge hole 190 T.
- a second discharge valve holding member 201 T as well as the second discharge valve 200 T is fixed by a rivet so as to restrict a deflection opening amount of the second discharge valve 200 T.
- the second muffler chamber 180 T reduces pressure pulsation of the discharged cooling medium.
- the first cylinder 121 S, the first end plate 160 S, the first muffler cover 170 S, the second cylinder 121 T, the second end plate 160 T, the second muffler cover 170 T, and the intermediate partition plate 140 are integrally fastened by a bolt that is not shown.
- an outer peripheral portion of the second end plate 160 T is fixedly bonded to the compressor housing 10 by spot welding to thereby fix the compressing section 12 to the compressor housing 10 .
- first and second through holes 101 and 102 are provided in an outer circumferential wall of the cylindrical compressor housing 10 to be axially away from each other in ascending order from a lower portion.
- An accumulator 25 T formed of an independent and cylindrical airtight container is arranged outside of the compressor housing 10 and held by an accumulator holder 251 and an accumulator band 253 .
- a system connecting pipe 255 connecting the accumulator 25 T to a low-pressure side of a refrigerating cycle is provided in a central portion of a top surface of the accumulator 25 T.
- First and second connecting pipes 31 S and 31 T each having one end extending toward an upper portion of an interior of the accumulator 25 T and the other end connected to the other end of first and second suction pipes 104 and 105 are connected to bottom through holes 257 provided at a bottom of the accumulator 25 T, respectively.
- the first and second connecting pipes 31 S and 31 T introducing a low-pressure cooling medium of the refrigerating cycle to the first and second compressing sections 12 S and 12 T via the accumulator 25 T are connected to first and second suction holes 135 S and 135 T of the first and second cylinders 121 S and 121 T via the first and second through holes 101 and 102 and the first and second suction pipes 104 , respectively.
- the first and second suction holes 135 S and 135 T communicate with the low-pressure side of the refrigerating cycle in parallel.
- Discharge portions of the first and second compressing sections 12 S and 12 T communicate with the interior of the compressor housing 10 via the first and second muffler chambers 180 S and 180 H, respectively.
- the first and second discharge holes 190 S and 190 T communicating the first and second compression chambers 133 S and 133 T of the first and second cylinders 121 S and 121 T with the first and second muffler chambers 180 S and 180 H are provided in the first and second end plates 160 S and 160 T, and the first and second discharge valves 200 S and 200 T preventing backflow of the compressed cooling medium are disposed in the first and second discharge holes 190 S and 190 T, respectively.
- a discharge pipe 107 connected to a high-pressure side of the refrigerating cycle and discharging the high-pressure cooling medium toward the high-pressure side of the refrigerating cycle is connected to a top of the compressor housing 10 . accordingly, the first and second discharge holes 190 S and 190 T communicate with the high-pressure side of the refrigerating cycle.
- the compressor housing 10 is filled with lubricating oil almost up to a height of the second cylinder 121 T.
- the lubricating oil circulates in the compressing section 12 by a vane pump, not shown, attached to a lower portion of the rotary shaft 15 and seals a portion defining the first and second working chambers 130 S and 130 T (compression spaces) for the compressed cooling medium by lubrication of sliding components and narrow gaps.
- First and second auxiliary discharge holes 190 SS and 190 TT are provided at positions from the first and second vane grooves 128 S and 128 T by 230° to 300° in a direction of revolution of the first and second pistons 125 S and 125 T along the first and second cylinder inner walls 123 S and 123 T, respectively.
- the arrangement is similar to that of the auxiliary discharge hole 190 A according to the first embodiment since the two cylinders 121 S and 121 T are arranged in parallel and equal in responsible pressure ratio.
- the first and second auxiliary discharge holes 190 SS and 190 TT are provided in the first and second end plates 160 S and 160 T of the first and second compressing sections 12 S and 12 T, respectively.
- an auxiliary hole may be provided only in one of the end plates.
- the cooling medium flowing from the low-pressure side of the refrigerating cycle into the accumulator 25 T through the system connecting pipe 255 is separated into a liquid cooling medium and a gas cooling medium. Specifically, the liquid cooling medium is accumulated in a lower portion of the accumulator 25 T and the gas cooling medium is accumulated in an upper portion thereof.
- the gas cooling medium in the accumulator 25 T is absorbed into the first and second suction chambers 131 S and 131 T of the first and second compressing sections 12 S and 12 T through the first and second connecting pipes 31 S and 31 T, the first and second suction pipes 104 , and the first and second suction holes 135 S and 135 T.
- the first and second suction chambers 131 S and 131 T are cut off from the first and second suction holes 135 S and 135 T and changed over to the first and second compression chambers 133 S and 133 T, and the cooling medium is compressed in the first and second compression chambers 133 S and 133 T.
- each of the first and second compression chambers 133 S and 133 T becomes equal to the pressure of each of the first and second muffler chambers 180 S and 180 T located downstream of the first and second discharge valves 200 S and 200 T provided in the first and second discharge hole 190 S and 190 T and the first and second auxiliary discharge holes 190 SS and 190 TT, respectively, then the first and second discharge valves 200 S and 200 T open, and the cooling medium is discharged into the first and second muffler chambers 180 S and 180 T through the first and second discharge holes 190 S and 190 T and the first and second auxiliary discharge holes 190 SS and 190 TT at low flow resistance and the pressure pulsation causing noise is reduced in the first muffler chamber 180 S.
- the cooling medium is discharged, as a high-pressure cooling medium, into the compressor housing 10 . Thereafter, the high-pressure cooling medium is fed to an upper portion of the motor 11 through a core notch, not shown, of the stator 111 of the motor 11 and gaps between a core and a coil and discharged toward the high-pressure side of the refrigerating cycle through the discharge pipe 107 .
- the cooling medium is discharged into the compressor housing 10 through the first and second discharge holes 190 S and 190 T and the first and second auxiliary discharge holes 190 SS and 190 TT at the low flow resistance. Therefore, the over-compression loss can be reduced.
- FIG. 16 is a top view of a compressing section of a rotary compressor according to a fourth embodiment of the present invention.
- FIG. 17 is a top view of the compressing section of the rotary compressor according to the first embodiment for reference.
- a discharge groove 124 communicating with a discharge hole 190 is provided in a region of a cylinder inner wall 123 corresponding to a position of the discharge hole 190 provided in one end plate 160 A but no discharge groove is provided in a region of the cylinder inner wall 123 corresponding to a position of an auxiliary discharge hole 190 A.
- a discharge groove 124 A is provided in the region of the cylinder inner wall 123 corresponding to the position of the auxiliary discharge hole 190 A similarly to the rotary compressor 1 according to the first embodiment shown in FIG. 1 , the cooling medium compressed in the compression chamber 133 leaks into the suction chamber 131 through narrow gaps between corners of the discharge groove 124 A and the piston 125 when the eccentric section 152 of the piston 125 passes through the position of the discharge groove 124 A.
- a center of the auxiliary discharge hole 190 A is located inward of the cylinder inner wall 123 and no discharge groove is provided in the region of the cylinder inner wall 123 corresponding to the position of the auxiliary discharge hole 190 A, the cooling medium leaking from the compression chamber 133 into the suction chamber 131 can be reduced. Accordingly, efficiency can be improved, as compared with the case in which the discharge groove 124 is provided.
- the auxiliary discharge hole different from the discharge hole is provided in one end plate in which the discharge hole is provided to increase a total area of the discharge hole. Therefore, there is no need to work a concave portion for the discharge hole, the valve seat around the discharge hole, and the discharge valve to be provided on each of both end plates. It is thereby possible to reduce working cost.
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Abstract
A rotary compressor includes a compressing section including a cylindrical cylinder, two end plates closing both ends of the cylinder, respectively, and a piston held by an eccentric section of a rotary shaft driven to rotate by a motor. A working chamber is formed between the piston and the cylinder inner wall. The rotary compressor also includes a vane protruding from within a vane groove of the cylinder into the working chamber; an airtight compressor housing accommodating therein the compressing section; a suction hole provided in the cylinder and communicating the suction chamber with a low-pressure side of a refrigerating cycle; and a discharge hole provided in one of the end plates and communicating the compression chamber with a high-pressure side of the refrigerating cycle. An auxiliary discharge hole different from the discharge hole is provided in the one end plate.
Description
- 1. Field of the Invention
- The present invention relates to a rotary compressor used in a refrigerating cycle of an air-conditioner.
- 2. Description of the Related Art
- There is conventionally known a rotary compressor configured so that a rotary compressor element and an electric element that drives the compressor element are pressed into and held in a cylindrical airtight container with an internal pressure of the container kept high. Furthermore, the rotary compressor is configured so that a discharge port (discharge hole) and a discharge valve opened or closed according to a magnitude of a discharge pressure are provided in each of an upper bearing (end plate) closing an upper opening of a cylindrical compression chamber of a cylinder and forming one bearing of a rotary shaft of the electric element and a lower bearing (end plate) closing a lower opening of the compression chamber and forming another bearing of the rotary shaft. The rotary compressor of this type is disclosed in, for example, Japanese Utility Model Application Laid-Open No. S56-175594.
- There is also known a two-stage rotary compressor configured so that two stages of rotary compressing sections are stacked and so that a compression target fluid is compressed by the low-stage compressing section and the high-stage compressing section by two stages. Furthermore, the two-stage rotary compressor is configured so that an inside diameter of a compression chamber of the low-stage compressing section is set larger than that of a compression chamber of the high-stage compressing section. Moreover, a second discharge valve chamber (discharge hole) of the low-stage compressing section different from a first discharge valve chamber provided in a main bearing (end plate) is arranged at a position of a partition plate dividing a compressing section into the low-stage compressing section and the high-stage compressing section, which portion corresponds to an outer portion of the compression chamber of the low-stage compressing section. The compressor of this type is disclosed in, for example, Japanese Patent Application Laid-Open No. S63-272988.
- Furthermore, there is known a compressor configured to include, in an airtight container, an electric element and a compressor element driven by the electric element and including a compression chamber that compresses a cooling medium containing lubricating oil. The compression chamber includes an introduction port for introducing the cooling medium containing the lubricating oil into the compression chamber, a first discharge port from which the compressed cooling medium is discharged, and a second discharge port from which the lubricating oil is discharged. A first discharge valve opened when a pressure of the compressed cooling medium reaches a first pressure in the compression chamber is provided in the first discharge port. A second discharge valve opened at a second pressure higher than the first pressure is provided in the second discharge port. The compressor of this type is disclosed in, for example, Japanese Patent Application Laid-Open No. 2006-275035.
- An inverter-type rotary compressor has the following problems. Particularly during high-speed rotation, over-compression loss caused by a flow resistance of the cooling medium in the discharge port increases and the loss causes deterioration in efficiency of the rotary compressor. If a diameter of the discharge hole is increased to reduce the flow resistance, it is necessary to increase a thickness of the valve to ensure strength of the discharge port. If the valve is thicker, opening of the valve delays, resulting in the over-compression loss.
- Moreover, according to the technique disclosed in Japanese Utility Model Application Laid-Open No. S56-175594, the discharge ports (discharge holes) are provided in both of the upper and lower bearings, respectively. Due to this, the structure of the compressing section is complicated, resulting in an increase in manufacturing cost of the rotary compressor. According to the technique disclosed in the Japanese Patent Application Laid-Open No. S63-272988, the discharge valve chambers (discharge holes) are provided in both the main baring and the partition plate, respectively. Similarly to the technique disclosed in Japanese Utility Model Application Laid-Open No. 56-175594, the structure of each of the compressing sections is complicated, resulting in an increase in manufacturing cost of the rotary compressor.
- According to the conventional technique disclosed in Japanese Patent Application Laid-Open No. 2006-275035, if the compressor is actuated to perform only cooling operation in a refrigerating and cooling cycle, a cooling medium gas inlet path on a front-stage (low-stage) compressing section of the two-stage compressor is completely cut off and the cooling medium gas is sucked in only from a rear-stage (high-stage) compressing section. At this time, a pressure of the front-stage (low-stage) compressing section is close to vacuum, the lubricating oil is impregnated into the front-stage compressing section from narrow gaps formed by components constituting a compression chamber of the front-side compressing section, and the compression chamber turns into a liquid compression state, thereby disadvantageously and greatly deteriorating efficiency of the compressor. The second discharge port is intended to discharge the lubricating oil from the compression chamber so as to prevent the deterioration in efficiency. Accordingly, during high-speed rotation of the compressor, the second discharge port is disadvantageously incapable of reducing the over-compression loss caused by the flow resistance of the cooling medium in the discharge port.
- It is an object of the present invention to at least partially solve the problems in the conventional technology.
- According to an aspect of the present invention, a rotary compressor includes a compressing section. The compressing section includes a cylindrical cylinder; two end plates closing both ends of the cylinder, respectively; a piston held by an eccentric section of a rotary shaft driven to rotate by a motor, and revolving in the cylinder along a cylinder inner wall of the cylinder, a working chamber being formed between the piston and the cylinder inner wall; and a vane protruding from within a vane groove of the cylinder into the working chamber, abutting on the piston, and dividing the working chamber into a suction chamber and a compression chamber. The rotary compressor also includes an airtight compressor housing accommodating therein the compressing section; a suction hole provided in the cylinder and communicating the suction chamber with a low-pressure side of a refrigerating cycle; and a discharge hole provided in one of the end plates and communicating the compression chamber with a high-pressure side of the refrigerating cycle. In the one end plate, an auxiliary discharge hole different from the discharge hole is provided.
- According to another aspect of the present invention, a rotary compressor includes a low-stage compressing section and a high-stage compressing section stacked on the low-stage compressing section via an intermediate partition plate. The low-stage compressing section includes a cylindrical low-stage cylinder; a low-stage end plate closing one end of the low-stage cylinder; a low-stage piston held by a low-stage eccentric section of a rotary shaft driven to rotate by a motor and revolving in the low-stage cylinder along a low-stage cylinder inner wall of the low-stage cylinder, a low-stage working chamber being formed between the low-stage piston and the low-stage cylinder inner wall; and a low-stage vane protruding from within a low-stage vane groove of the low-stage cylinder into the low-stage working chamber, abutting on the low-stage piston, and dividing the low-stage working chamber into a low-stage suction chamber and a low-stage compression chamber. The high-stage compressing section includes a cylindrical high-stage cylinder; a high-stage end plate closing one end of the high-stage cylinder; a high-stage piston held by a high-stage eccentric section of the rotary shaft driven to rotate by the motor and revolving in the high-stage cylinder along a high-stage cylinder inner wall of the high-stage cylinder, a high-stage working chamber being formed between the high-stage piston and the high-stage cylinder inner wall; and a high-stage vane protruding from within a high-stage vane groove of the high-stage cylinder into the high-stage working chamber, abutting on the high-stage piston, and dividing the high-stage working chamber into a high-stage suction chamber and a high-stage compression chamber. The rotary compressor also includes an airtight compressor housing accommodating therein the low-stage compressing section and the high-stage compressing section; a low-stage suction hole provided in the low-stage cylinder and communicating the low-stage suction chamber with a low-pressure side of a refrigerating cycle; a low-stage discharge hole provided in the low-stage end plate and communicating the low-stage compression chamber with a high-stage suction hole provided in the high-stage cylinder; and a high-stage discharge hole provided in the high-stage end plate and communicating the high-stage compression chamber with a high-pressure side of the refrigerating cycle. In the low-stage end plate, a low-stage auxiliary discharge hole different from the low-stage discharge hole is provided.
- The above and other objects, features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings.
-
FIG. 1 is a longitudinal sectional view of a rotary compressor according to a first embodiment of the present invention; -
FIG. 2 is a top view of a compressing section of the rotary compressor shown inFIG. 1 ; -
FIG. 3 is a perspective view of an upper surface of the compressing section closed by one of end plates; -
FIG. 4 is a chart showing the relationship between a revolution angle of a piston and a discharge pressure; -
FIG. 5 is a chart showing the relationship between the revolution angle of the piston and a change of a volume of a compression chamber; -
FIG. 6 is a chart showing the relationship between the revolution angle of the piston and a change rate of the volume of the compression chamber; -
FIG. 7 is a longitudinal sectional view of a rotary compressor according to a second embodiment of the present invention; -
FIG. 8 is a bottom view of a low-stage compressing section of the rotary compressor shown inFIG. 7 ; -
FIG. 9 is a cross-sectional view of a high-stage compressing section of the rotary compressor shown inFIG. 7 ; -
FIG. 10 is a perspective view of a lower surface of the low-stage compressing section closed by a low-stage end plate; -
FIG. 11 is a chart showing the relationship between a revolution angle of a piston and a discharge pressure of the low-stage compressing section; -
FIG. 12 is a bottom view of a low-stage compressing section of a rotary compressor according to a modification of the second embodiment; -
FIG. 13 is a perspective view of a lower surface of the low-stage compressing section closed by a low-stage end plate according to the modification of the second embodiment; -
FIG. 14 is a longitudinal sectional view of a rotary compressor according to a third embodiment of the present invention; -
FIG. 15 is a cross-sectional view of first and second compressing sections of the rotary compressor shown inFIG. 14 ; -
FIG. 16 is a top view of a compressing section of a rotary compressor according to a fourth embodiment of the present invention; and -
FIG. 17 is a top view of the compressing section of the rotary compressor according to the first embodiment for reference. - Exemplary embodiments of a rotary compressor according to the present invention will be described below with reference to the accompanying drawings. It is to be noted that the present invention is not limited to the embodiments.
-
FIG. 1 is a longitudinal sectional view of a rotary compressor according to a first embodiment of the present invention.FIG. 2 is a top view of a compressing section of the rotary compressor shown inFIG. 1 .FIG. 3 is a perspective view of an upper surface of the compressing section closed by one of end plates.FIG. 4 is a chart showing the relationship between a revolution angle of a piston and a pressure of a compression chamber.FIG. 5 is a chart showing the relationship between the revolution angle of the piston and a volume of the compression chamber.FIG. 6 is a chart showing the relationship between the revolution angle of the piston and a change rate of the volume of the compression chamber. - As shown in
FIG. 1 , arotary compressor 1 according to the first embodiment includes, in an airtightcylindrical compressor housing 10, a compressingsection 12, and amotor 11 driving thecompressing section 12. - A
stator 111 of themotor 11 is fixedly shrunk to an inner circumferential surface of thecompressor housing 10. Arotor 112 of themotor 11 is arranged in a central portion of thestator 111 and fixedly shrunk to arotary shaft 15 mechanically connecting themotor 11 to thecompressing section 12. - As shown in
FIGS. 1 and 2 , the compressingsection 12 includes a shortcylindrical cylinder 121. A cylindrical cylinderinner wall 123 is formed on thecylinder 121 to be concentric with themotor 11. Acylindrical piston 125 having an outside diameter smaller than a diameter of the cylinderinner wall 123 is arranged in the cylinderinner wall 123, and a working chamber 130 (compression space) sucking in, compressing, and discharging a cooling medium is formed between the cylinderinner wall 123 and thepiston 125. - A
vane groove 128 is formed in thecylinder 121 in a range of an entire length of thecylinder 121 from the cylinderinner wall 123 in a radial direction of thecylinder 121. Aflat vane 127 is fitted into thevane groove 128. A spring, not shown, is arranged in an inner part of thevane groove 128. In a normal state, thevane 127 protrudes from within thevane groove 128 into the workingchamber 130 by a repulsive force of the spring, a tip end of thevane 127 abuts on an outer circumferential surface of thepiston 125, and thevane 127 divides the working chamber 130 (compression space) into asuction chamber 131 and acompression chamber 133. - A
backpressure introduction path 129 communicating the inner part of thevane groove 128 with an interior of thecompressor housing 10 and applying a backpressure to thevane 127 is formed on thecylinder 121. Asuction hole 135 communicating with thesuction chamber 131 is provided in thecylinder 121 to suck the cooling medium into thesuction chamber 131. - As shown in
FIG. 1 , oneend plate 160A is disposed on an upper end of thecylinder 121 and closes an upper portion of the workingchamber 130 of thecylinder 121. Theother end plate 160B is disposed on a lower end of thecylinder 121 and closes a lower portion of the workingchamber 130. - A
sub bearing 161B is formed on theother end plate 160B and asub bearing support 151 of therotary shaft 15 is rotatably supported by the sub bearing 161B. Amain bearing 161A is formed on oneend plate 160A and amain bearing support 153 of therotary shaft 15 is rotatably supported by themain bearing 161A. - The
rotary shaft 15 includes aneccentric section 152 and theeccentric section 152 rotatably holds thepiston 125 of the compressingsection 12. When therotary shaft 15 rotates, thepiston 125 revolves clockwise in thecylinder 121 along the cylinderinner wall 123 inFIGS. 2 and 3 and thevane 127 follows to reciprocate. Volumes of thesuction chamber 131 and thecompression chamber 133 continuously change by movements of thepiston 125 and thevane 127, and thecompressing section 121 continuously sucks in, compresses, and discharges the cooling medium. - As shown in
FIG. 1 , amuffler cover 170 is disposed above oneend plate 160A and amuffler chamber 180 is formed between themuffler cover 170 and theend plate 160A. A discharge portion of the compressingsection 12 communicates with the interior of thecompressor housing 10 via themuffler chamber 180. Accordingly, adischarge hole 190 communicating thecompression chamber 133 of thecylinder 121 with themuffler chamber 180 is provided in oneend plate 160A near thevane 127 and adischarge valve 200 preventing backflow of the compressed cooling medium is provided in thedischarge hole 190. - Furthermore, a discharge
valve holding member 201 as well as thedischarge valve 200 is fixed to theend plate 160A by a rivet so as to restrict a deflection opening amount of thedischarge valve 200. Themuffler chamber 180 reduces pressure pulsation of the discharged cooling medium. - The
other end plate 160B, thecylinder 121, oneend plate 160A, and themuffler cover 170 are integrally fastened by a bolt that is not shown. Among the integrally fastened constituent elements of the compressingsection 12, an outer peripheral portion of oneend plate 160A is fixedly bonded to thecompressor housing 10 by spot welding to thereby fix thecompressing section 12 to thecompressor housing 10. - As shown in
FIG. 1 , a throughhole 101 is provided in an outer circumferential wall of thecylindrical compressor housing 10. Anaccumulator 25 formed of an independent and cylindrical airtight container is arranged outside of thecompressor housing 10 and held by anaccumulator holder 251 and anaccumulator band 253. - A
system connecting pipe 255 connecting theaccumulator 25 to a low-pressure side of a refrigerating cycle is provided in a central portion of a top surface of theaccumulator 25. A low-pressure connecting pipe 31 having one end extending toward an upper portion of an interior of theaccumulator 25 and the other end connected to the other end of asuction pipe 104 is connected to a bottom throughhole 257 provided at a bottom of theaccumulator 25. - The low-
pressure connecting pipe 31 introducing a low-pressure cooling medium of the refrigerating cycle to thecompressing section 12 via theaccumulator 25 is connected to the suction hole 135 (seeFIG. 2 ) via the throughhole 101 and thesuction pipe 104. Accordingly, thesuction hole 135 communicates with the low-pressure side of the refrigerating cycle. - A
discharge pipe 107 connected to a high-pressure side of the refrigerating cycle and discharging a high pressure cooling medium toward the high-pressure side of the refrigerating cycle is connected to a top of thecompressor housing 10. Accordingly, thedischarge hole 190 communicates with the high-pressure side of the refrigerating cycle. - The
compressor housing 10 is filled with lubricating oil almost up to a height of thecylinder 121. The lubricating oil circulates in thecompressing section 12 by a vane pump, not shown, attached to a lower portion of therotary shaft 15 and seals a portion defining the working chamber 130 (compression space) for the compressed cooling medium by lubrication of sliding components and narrow gaps. - As shown in
FIG. 3 , therotary compressor 1 according to the first embodiment is characteristically configured so that anauxiliary discharge hole 190A communicating thecompression chamber 133 with the high-pressure side of the refrigerating cycle is provided in oneend plate 160A in which thedischarge hole 190 is provided. Thedischarge valve 200 and the dischargevalve holding member 201 are disposed in theauxiliary discharge hole 190A similarly to thedischarge hole 190. - As shown in
FIGS. 2 and 3 , adischarge groove 124 communicating with thedischarge hole 190 is provided in a region of the cylinderinner wall 123 corresponding to a position of thedischarge hole 190 provided in oneend plate 160A. Adischarge groove 124A communicating with theauxiliary discharge hole 190A is provided in a region of the cylinderinner wall 123 corresponding to a position of theauxiliary discharge hole 190A. Thedischarge grooves compression chamber 133 into thedischarge hole 190 and theauxiliary discharge hole 190A. - The
auxiliary discharge hole 190A is provided at a position away from thevane groove 128 by 230° to 300° in a direction of revolution of thepiston 125 along the cylinderinner wall 123. The reason is as follows. As shown inFIG. 3 ,concave portions 190K and 190AK are provided in theend plate 160A separately to accommodate thedischarge valves 200 and the discharge valve holding members 201 (seeFIG. 1 ) preventing backflow of the cooling medium in thedischarge hole 190 and theauxiliary discharge hole 190A, respectively. If theconcave portions 190K and 190AK interfere with each other, arib 190R wears away and strength of theend plate 160A weakens. To prevent this, theauxiliary discharge hole 190A is provided at the position within 300° from thevane groove 128 in the direction of revolution of thepiston 125 along the cylinderinner wall 123. - On the other hand, as shown in
FIG. 4 , when thepiston 125 revolves clockwise by about 210° from the position of thevane groove 128, a pressure of thecompression chamber 133 reaches a discharge pressure according to rated cooling conditions and thedischarge valves 200 that have closed thedischarge hole 190 and theauxiliary discharge hole 190A, respectively are opened. Furthermore, as shown inFIG. 6 , therotary compressor 1 has a high change rate of a volume of thecompression chamber 133, that is, a high discharge flow speed when thepiston 125 revolves by 135° to 225° from the position of thevane groove 128. - Accordingly, right after the
discharge valve 200 opens by 210°, a flow speed of the discharged cooling medium is the highest and pressure loss is the greatest. If theauxiliary discharge hole 190A is communicable without being cut off by end surfaces of thecompression chamber 133 and thepiston 125 right after thedischarge valve 200 opens by 210°, theauxiliary discharge hole 190A operates effectively. Due to this, theauxiliary discharge hole 190A is provided at the position away from thevane groove 128 at least by 230° in the direction of the revolution of thepiston 125 along the cylinderinner wall 123. However, in the present invention, the position of theauxiliary discharge hole 190A is not limited to the above-stated position. As long as theauxiliary discharge hole 190A is used under conditions that the strength of theend plate 160A is sufficiently high, therib 190R may not be provided and theauxiliary discharge hole 190A may be provided at a position away from thevane groove 128 by 300° or more. - Operation of the
rotary compressor 1 described so far will next be described. If therotary compressor 1 is actuated, the cooling medium flowing from the low-pressure side of the refrigerating cycle into theaccumulator 25 through thesystem connecting pipe 255 is separated into a liquid cooling medium and a gas cooling medium. Specifically, the liquid cooling medium is accumulated in a lower portion of theaccumulator 25 and the gas cooling medium is accumulated in an upper portion thereof. - When the
piston 125 revolves in thecylinder 121 and a volume of thesuction chamber 131 increases, the gas cooling medium in theaccumulator 25 is sucked into thesuction chamber 131 of the compressingsection 12 through the low-pressure connecting pipe 31, thesuction pipe 104, and thesuction hole 135. When thepiston 125 revolves once, thesuction chamber 131 is cut off from thesuction hole 135 and changed over to thecompression chamber 133, and the cooling medium is compressed in thecompression chamber 133. - If the pressure of the compressed cooling medium in the
compression chamber 133 becomes equal to a pressure of themuffler chamber 180 located downstream of thedischarge valves 200 provided in thedischarge hole 190 and theauxiliary discharge hole 190A, respectively, that is, discharge pressure, then thedischarge valves 200 open, and the cooling medium is discharged into themuffler chamber 180 through thedischarge hole 190 and theauxiliary discharge hole 190A at low flow resistance and the pressure pulsation causing noise is reduced in themuffler chamber 180. The cooling medium is discharged, as a high-pressure cooling medium, into thecompressor housing 10. Thereafter, the high-pressure cooling medium is fed to an upper portion of themotor 11 through a core notch, not shown, of thestator 111 of themotor 11 and a gap between a core and a coil, and discharged toward the high-pressure side of the refrigerating cycle through thedischarge pipe 107. - In the
rotary compressor 1 according to the first embodiment, the cooling medium is discharged into themuffler chamber 180 through thedischarge hole 190 and theauxiliary discharge hole 190A at the low flow resistance. Therefore, the over-compression loss can be reduced. Further, there is no need to work theconcave portion 190K accommodating therein thedischarge hole 190, the valve seat around thedischarge hole 190, and thedischarge valve 200 to be provided on each of theend plates -
FIG. 7 is a longitudinal sectional view of a rotary compressor according to a second embodiment of the present invention.FIG. 8 is a bottom view of a low-stage compressing section of the rotary compressor shown inFIG. 7 .FIG. 9 is a cross-sectional view of a high-stage compressing section of the rotary compressor shown inFIG. 7 .FIG. 10 is a perspective view of a lower surface of the low-stage compressing section closed by a low-stage end plate.FIG. 11 is a chart showing the relationship between a revolution angle of a piston and a discharge pressure of the low-stage compressing section.FIG. 12 is a bottom view of a low-stage compressing section of a rotary compressor according to a modification of the second embodiment.FIG. 13 is a perspective view of a lower surface of the low-stage compressing section closed by a low-stage end plate according to the modification of the second embodiment. - As shown in
FIG. 7 , arotary compressor 2 according to the second embodiment includes, in an airtightcylindrical compressor housing 10, a compressingsection 12 and amotor 11 driving thecompressing section 12. - A
stator 111 of themotor 11 is fixedly shrunk to an inner circumferential surface of thecompressor housing 10. Arotor 112 of themotor 11 is arranged in a central portion of thestator 111 and fixedly shrunk to arotary shaft 15 mechanically connecting themotor 11 to thecompressing section 12. - The compressing
section 12 includes a low-stage compressing section 12L and a high-stage compressing section 12H connected in series to the low-stage compressing section 12L and disposed to be stacked on an upper side of the low-stage compressing section 12L. As shown inFIGS. 7 and 8 , the low-stage compressing section 12L includes a shortcylindrical cylinder 121L. As shown inFIGS. 7 and 9 , the high-stage compressing section 12H includes a shortcylindrical cylinder 121H. - Cylindrical low-stage and high-stage cylinder
inner walls stage cylinder 121L and the high-stage cylinder 121H to be concentric with themotor 11, respectively. Cylindrical low-stage and high-stage pistons inner walls inner walls stage working chambers inner walls stage pistons 125L and 124H, respectively. - Low-stage and high-
stage vane grooves stage cylinders stage cylinders inner walls stage cylinders flat vanes stage vane grooves - To make a volume of the high-
stage working chamber 130H of the high-stage compressing section 12H smaller than that of the low-stage working chamber 130L of the low-stage compressing section 12L, the high-stage cylinder 121H, the high-stage piston 125H, and the high-stage vane 127H are set lower in axial height than the low-stage cylinder 121L, the low-stage piston 125L, and the low-stage vane 127L, respectively. - Low-stage and high-stage springs, not shown, are arranged in inner parts of the low-stage and high-
stage vane grooves stage vanes stage vane grooves stage working chambers stage vanes stage pistons stage vanes stage working chambers stage suction chambers stage compression chambers - Low-stage and high-stage
backpressure introduction paths stage vane grooves compressor housing 10 and applying a backpressure to the low-stage and high-stage vanes stage cylinders - Low-stage and high-stage suction holes 135L and 135H communicating with the low-stage and high-
stage suction chambers stage cylinders stage suction chambers - As shown in
FIG. 7 , anintermediate partition plate 140 is provided between the low-stage cylinder 121L and the high-stage cylinder 121H to divide a working chamber into the low-stage working chamber 130L of the low-stage cylinder 121L and the high-stage working chamber 130H of the high-stage cylinder 121H. A low-stage end plate 160L is disposed on a lower end of the low-stage cylinder 121L and closes the low-stage working chamber 130L of the low-stage cylinder 121L. A high-stage end plate 160H is disposed on an upper end of the high-stage cylinder 121H and closes the high-stage working chamber 130H of the high-stage cylinder 121H. - A sub bearing 161L is formed on the low-
stage end plate 160L and asub bearing support 151 of therotary shaft 15 is rotatably supported by the sub bearing 161L. Amain bearing 161H is formed on the high-stage end plate 160H and amain bearing support 153 of therotary shaft 15 is rotatably supported by themain bearing 161H. - The
rotary shaft 15 includes low-stage and high-stageeccentric sections eccentric section 152L rotatably holds the low-stage piston 125L of the low-stage compressing section 12L. The high-stageeccentric section 152H rotatably holds the high-stage piston 125H of the high-stage compressing section 12H. - When the
rotary shaft 15 rotates, the low-stage and high-stage pistons stage cylinders inner walls FIG. 8 (revolve counterclockwise inFIG. 9 ), and the low-stage and high-stage vanes stage suction chambers stage compression chambers stage pistons stage vanes compressing section 12 continuously absorbs, compresses, and discharges the cooling medium. - As shown in
FIG. 7 , a low-stage muffler cover 170L is disposed below the low-stage end plate 160L and a low-stage muffler chamber 180L is formed between the low-stage muffler cover 170L and the low-stage end plate 160L. A discharge portion of the low-stage compressing section 12L opens to the low-stage muffler chamber 180L. Accordingly, a low-stage discharge hole 190L communicating the low-stage compression chamber 133L of the low-stage cylinder 121L with the low-stage muffler chamber 180L is provided in the low-stage end plate 160L near the low-stage vane 127L and a low-stage discharge valve 200L preventing backflow of the compressed cooling medium is provided in the low-stage discharge hole 190L. - As shown in
FIG. 10 , the low-stage muffler chamber 180L is one annularly communicable chamber and a part of an intermediate communicating path communicating a discharge side of the low-stage compressing section 12L with a suction side of the high-stage compressing section 12H. The low-stage muffler chamber 180L reduces pressure pulsation of the discharged cooling medium. - Furthermore, a low-stage discharge
valve holding member 201L as well as the low-stage discharge valve 200L is fixed to the low-stage end plate 160L by a rivet so as to restrict a deflection opening amount of the low-stage discharge valve 200L. A low-stagemuffler discharge hole 210L discharging the cooling medium in the low-stage muffler chamber 180L to outside is provided in an outer peripheral wall of the low-stage end plate 160L. The low-stagemuffler discharge hole 210L is provided radially at a position in a circumferential direction of thecompressor housing 10 and different in phase from the low-stage and high-stage suction holes 135L and 135H of the compressingsection 12. - As shown in
FIG. 7 , a high-stage muffler cover 170H is disposed above the high-stage end plate 160H and a high-stage muffler chamber 180H is formed between the high-stage muffler cover 170H and the high-stage end plate 160H. A high-stage discharge hole 190H communicating the high-stage compression chamber 133H of the high-stage cylinder 121H with the high-stage muffler chamber 180H is provided in the high-stage end plate 160H near the high-stage vane 127H and a high-stage discharge valve 200H preventing backflow of the compressed cooling medium is provided in the high-stage discharge hole 190H. Furthermore, a high-stage dischargevalve holding member 201H as well as the high-stage discharge valve 200H is fixed to the high-stage end plate 160H by a rivet so as to restrict a deflection opening amount of the high-stage discharge valve 200H. The high-stage muffler chamber 180H reduces pressure pulsation of the discharged cooling medium. - The low-
stage cylinder 121L, the low-stage end plate 160L, the low-stage muffler cover 170L, the high-stage cylinder 121H, the high-stage end plate 160H, the high-stage muffler cover 170H, and theintermediate partition plate 140 are integrally fastened by a bolt that is not shown. Among the integrally fastened constituent elements of the compressingsection 12, an outer peripheral portion of the high-stage end plate 160H is fixedly bonded to thecompressor housing 10 by spot welding to thereby fix thecompressing section 12 to thecompressor housing 10. - As shown in
FIG. 7 , first, second, and third throughholes cylindrical compressor housing 10 to be axially away from one another in ascending order from a lower portion. Anaccumulator 25 formed of an independent and cylindrical airtight container is arranged outside of thecompressor housing 10 and held by anaccumulator holder 251 and anaccumulator band 253. - A
system connecting pipe 255 connecting theaccumulator 25 to a low-pressure side of a refrigerating cycle is provided in a central portion of a top surface of theaccumulator 25. A low-pressure connecting pipe 31 having one end extending toward an upper portion of an interior of theaccumulator 25 and the other end connected to the other end of asuction pipe 104 is connected to a bottom throughhole 257 provided at a bottom of theaccumulator 25. - The low-
pressure connecting pipe 31 introducing a low-pressure cooling medium of the refrigerating cycle to thecompressing section 12 via theaccumulator 25 is connected to the low-stage suction hole 135L of the low-stage cylinder 121L via the second throughhole 102 and the low-stage suction pipe 104. Accordingly, the low-stage suction hole 135L communicates with the low-pressure side of the refrigerating cycle. - One end of the low-
stage discharge pipe 105 is connected to the low-stagemuffler discharge hole 210L of the low-stage muffler chamber 180L through the first throughhole 101. One end of the high-stagedischarge suction pipe 106 is connected to the high-stage suction hole 135H of the high-stage cylinder 121H through the third throughhole 103. Further, the other end of the low-stage discharge pipe 105 is connected to the other end of the high-stage suction pipe 106 by an intermediate connectingpipe 23. A low-pressure connecting pipe 31 and the intermediate connectingpipe 23 are formed so as not to interfere with each other. - A discharge portion of the high-
stage compressing section 12H communicates with the interior of thecompressor housing 10 via the high-stage muffler chamber 180H. Namely, the high-stage discharge hole 190H communicating the high-stage compression chamber 133H of the high-stage cylinder 121H with the high-stage muffler chamber 180H is provided in the high-stage end plate 160H, and the high-stage discharge valve 200H preventing backflow of the compressed cooling medium is disposed in the high-stage discharge hole 190H. - A
discharge pipe 107 connected to a high-pressure side of the refrigerating cycle and discharging the high-pressure cooling medium toward the high-pressure side of the refrigerating cycle is connected to a top of thecompressor housing 10. Accordingly, the high-stage discharge hole 190H communicates with the high-pressure side of the refrigerating cycle. - The
compressor housing 10 is filled with lubricating oil almost up to a height of the high-stage cylinder 121H. The lubricating oil circulates in thecompressing section 12 by a vane pump, not shown, attached to a lower portion of therotary shaft 15 and seals a portion defining the low-stage and high-stage working chambers - As shown in
FIG. 10 , therotary compressor 2 according to the second embodiment is characteristically configured so that a low-stage auxiliary discharge hole 190LL communicating the low-stage compression chamber 133L with the high-stage compressing section 12H is provided in the low-stage end plate 160L in which the low-stage discharge hole 190L is provided. A low-stage discharge valve 200L is disposed in the low-stage auxiliary discharge hole 190LL similarly to the low-stage discharge hole 190L. - As shown in
FIGS. 8 and 10 , adischarge groove 124L communicating with the low-stage discharge hole 190L is provided in a region of the low-stage cylinderinner wall 123L corresponding to a position of the low-stage discharge hole 190L provided in the low-stage end plate 160L. A discharge groove 124LA communicating with the low-stage auxiliary discharge hole 190LL is provided in a region of the low-stage cylinderinner wall 123L corresponding to a position of the low-stage auxiliary discharge hole 190LL. Thedischarge grooves 124L and 124LA reduce the flow resistance of the cooling medium discharged from the low-stage compression chamber 133L into the low-stage discharge hole 190L and the low-stage auxiliary discharge hole 190LL. - The low-stage auxiliary discharge hole 190LL is provided at a position away from the low-
stage vane groove 128L by 190° to 300° in a direction of revolution of the low-stage piston 125L along the low-stage cylinderinner wall 123L. The reason for providing the low-stage auxiliary discharge hole 190LL at the position within 300° is the same as that described in the first embodiment. - On the other hand, as shown in
FIG. 11 , when the low-stage piston 125L revolves clockwise by about 170° from the position of the low-stage vane groove 128L, a pressure of the low-stage compression chamber 133L reaches a low-stage discharge pressure (an intermediate pressure) and the low-stage discharge valves 200L that have closed the low-stage discharge hole 190L and the low-stage auxiliary discharge hole 190LL, respectively are opened. In other words, since a pressure ratio is lower than that according to the first embodiment, the low-stage piston 125L opens quickly by about 40° as compared with the first embodiment. - Furthermore, similarly to the first embodiment, as shown in
FIG. 11 , therotary compressor 2 has a high change rate of a volume of the low-stage compression chamber 133L, that is, a high discharge flow speed when the low-stage piston 125L revolves by 135° to 225° from the position of the low-stage vane groove 128L. Accordingly, right after the low-stage discharge valve 200L opens by 170°, a flow speed of the discharged cooling medium is the highest and pressure loss is the greatest. If the low-stage auxiliary discharge hole 190LL is communicable without being cut off by end surfaces of the low-stage compression chamber 133L and the low-stage piston 125L right after the low-stage discharge valve 200 opens by 170°, the low-stage auxiliary discharge hole 190LL operates effectively. Due to this, the low-stage auxiliary discharge hole 190LL is provided at the position away from the low-stage vane groove 128L at least by 190° in the direction of the revolution of the low-stage piston 125L along the low-stage cylinderinner wall 123L. - Operation of the
rotary compressor 2 described so far will next be described. If therotary compressor 2 is actuated, the cooling medium flowing from the low-pressure side of the refrigerating cycle into theaccumulator 25 through thesystem connecting pipe 255 is separated into a liquid cooling medium and a gas cooling medium. Specifically, the liquid cooling medium is accumulated in a lower portion of theaccumulator 25 and the gas cooling medium is accumulated in an upper portion thereof. - When the low-
stage piston 125L revolves in the low-stage cylinder 121L and a volume of the low-stage suction chamber 131L increases, the gas cooling medium in theaccumulator 25 is absorbed into the low-stage suction chamber 131L of the low-stage compressing section 12L through the low-pressure connecting pipe 31, the low-stage suction pipe 104L, and the low-stage suction hole 135. When the low-stage piston 125L revolves once, the low-stage suction chamber 131L is cut off from the low-stage suction hole 135L and changed over to the low-stage compression chamber 133L, and the cooling medium is compressed in the low-stage compression chamber 133L. - If the pressure of the compressed cooling medium in the low-
stage compression chamber 133L becomes equal to the pressure of the low-stage muffler chamber 180L located downstream of the low-stage discharge valves 200L provided in the low-stage discharge hole 190L and the low-stage auxiliary discharge hole 190LL, respectively, that is, the intermediate pressure (low-stage discharge pressure), then the low-stage discharge valves 200L open, and the cooling medium is discharged into the low-stage muffler chamber 180L through the low-stage discharge hole 190L and the low-stage auxiliary discharge hole 190LL at low flow resistance and the pressure pulsation causing noise is reduced in the low-stage muffler chamber 180L. Thereafter, the cooling medium is fed to the high-stage suction chamber 131H of the high-stage compressing section 12H through the low-stage discharge pipe 105, the intermediate connectingpipe 23, and the high-stage suction hole 135H. - The cooling medium fed to the high-
stage suction chamber 131H of the high-stage compressing section 12H is compressed and discharged by similar operation to that of the low-stage compressing section 12L and the pressure pulsation is reduced in the high-stage muffler chamber 180H. Thereafter, the cooling medium is discharged, as a high-pressure cooling medium, into thecompressor housing 10. Thereafter, the high-pressure cooling medium is fed to an upper portion of themotor 11 through a core notch, not shown, of thestator 111 of themotor 11 and a gap between a core and a coil, and discharged toward the high-pressure side of the refrigerating cycle through thedischarge pipe 107. - In the
rotary compressor 2 according to the second embodiment, the cooling medium is discharged into the low-stage muffler chamber 180L through the low-stage discharge hole 190L and the low-stage auxiliary discharge hole 190LL at the low flow resistance. Therefore, the over-compression loss can be reduced. Further, manufacturing cost can be reduced as compared with of the case in which the low-stage auxiliary discharge hole is provided in theintermediate partition plate 140. - Moreover, in the two-
stage rotary compressor 2, the pressure ratio is shared between the two compression chambers and the low-stage pressure ratio is generally, therefore, as low as 1.5 to 2.0. Accordingly, since the cooling medium is discharged from the compression chambers in a state in which a volume of the cooling medium is large, it is effective to provide the auxiliary discharge hole particularly for reduction of the over-compression loss (flow resistance). -
FIG. 12 is a bottom view of a low-stage compressing section according to a modification of the second embodiment.FIG. 13 is a perspective view of a lower surface of the low-stage compressing section closed by a low-stage end plate according to the modification of the second embodiment. In the modification of the second embodiment shown inFIGS. 12 and 13 ,concave portions 190K and 190AK provided in the low-stage end plate 160L are caused to interfere with each other, arib 190R is removed, a fixedportion 190S common to integrated L-shaped lower-stage discharge valve and lower-stage discharge valve holding member is provided, thereby providing an L-shaped concave portion. The L-shaped concave portion accommodates therein the integrated L-shaped lower-stage discharge valve and lower-stage discharge valve holding member for preventing backflow in the low-stage discharge hole 190L and the low-stage auxiliary discharge hole 190LL. - According to the modification of the second embodiment, it is possible to ensure that the low-
stage end plate 160L has sufficient strength by providing different concave portions near the low-stage discharge hole 190L and the low-stage auxiliary discharge hole 190LL, respectively. It is also possible to integrate the low-stage discharge valve with the low-stage discharge valve holding member by making only the fixedportion 190S common to the low-stage discharge valve and the low-stage discharge valve holding member. Cost can be thereby reduced. -
FIG. 14 is a longitudinal sectional view of a rotary compressor according to a third embodiment of the present invention.FIG. 15 is a cross-sectional view of a second compressing section of the rotary compressor shown inFIG. 14 . - As shown in
FIG. 14 , arotary compressor 3 according to the third embodiment includes, in an airtightcylindrical compressor housing 10, a compressingsection 12 and amotor 11 driving thecompressing section 12. - A
stator 111 of themotor 11 is fixedly shrunk to an inner circumferential surface of thecompressor housing 10. Arotor 112 of themotor 11 is arranged in a central portion of thestator 111 and fixedly shrunk to arotary shaft 15 mechanically connecting themotor 11 to thecompressing section 12. - The compressing
section 12 includes afirst compressing section 12S and asecond compressing section 12T connected in parallel to thefirst compressing section 12S and disposed to be stacked on an upper side of thefirst compressing section 12S. The first andsecond compressing sections cylindrical cylinders - As shown in
FIG. 15 , circular first and second cylinderinner walls first cylinder 121S and thesecond cylinder 121T to be concentric with themotor 11, respectively. Cylindrical first andsecond pistons inner walls inner walls chambers inner walls second pistons 125S and 124T, respectively. - First and
second vane grooves second cylinders second cylinders inner walls second cylinders flat vanes second vane grooves - To make a volume of the
second working chamber 130T of thesecond compressing section 12T smaller than that of the first workingchamber 130S of thefirst compressing section 12S, thesecond cylinder 121T, thesecond piston 125T, and thesecond vane 127T are set lower in axial height than thefirst cylinder 121S, thefirst piston 125S, and thefirst vane 127S, respectively. - First and second springs, not shown, are arranged in inner parts of the first and
second vane grooves second vanes second vane grooves chambers second vanes second pistons second vanes chambers second suction chambers - First and second
backpressure introduction paths second vane grooves compressor housing 10 and applying a backpressure to the first andsecond vanes second cylinders - First and
second suction holes second suction chambers second cylinders second suction chambers - As shown in
FIG. 14 , anintermediate partition plate 140 is provided between thefirst cylinder 121S and thesecond cylinder 121T to divide a working chamber into the first workingchamber 130S of thefirst cylinder 121S and thesecond working chamber 130T of thesecond cylinder 121T. Afirst end plate 160S is disposed on a lower end of thefirst cylinder 121S and closes the first workingchamber 130S of thefirst cylinder 121S. Asecond end plate 160T is disposed on an upper end of thesecond cylinder 121T and closes thesecond working chamber 130T of thesecond cylinder 121T. - A sub bearing 161S is formed on the
first end plate 160S and asub bearing support 151 of therotary shaft 15 is rotatably supported by the sub bearing 161S. Amain bearing 161T is formed on thesecond end plate 160T and amain bearing support 153 of therotary shaft 15 is rotatably supported by themain bearing 161T. - The
rotary shaft 15 includes first and secondeccentric sections eccentric section 152S rotatably holds thefirst piston 125S of thefirst compressing section 12S. The secondeccentric section 152T rotatably holds thesecond piston 125T of thesecond compressing section 12T. - When the
rotary shaft 15 rotates, the first andsecond pistons second cylinders inner walls second vanes second suction chambers second pistons second vanes compressing section 12 continuously absorbs, compresses, and discharges the cooling medium. - As shown in
FIG. 14 , afirst muffler cover 170S is disposed below thefirst end plate 160S and afirst muffler chamber 180S is formed between thefirst muffler cover 170S and thefirst end plate 160S. A discharge portion of thefirst compressing section 12S opens to thefirst muffler chamber 180S. Namely, afirst discharge hole 190S communicating the first compression chamber 133S of thefirst cylinder 121S with thefirst muffler chamber 180S is provided in thefirst end plate 160S near thefirst vane 127S and afirst discharge valve 200S preventing backflow of the compressed cooling medium is provided in thefirst discharge hole 190S. - The
first muffler chamber 180S is one annularly communicable chamber and a part of an intermediate communicating path communicating a discharge side of thefirst compressing section 12S with the interior of thecompressor housing 10. Thefirst muffler chamber 180S reduces pressure pulsation of the discharged cooling medium. - Furthermore, a first discharge
valve holding member 201S as well as thefirst discharge valve 200S is fixed on thefirst discharge valve 200S by a rivet so as to restrict a deflection opening amount of thefirst discharge valve 200S. - As shown in
FIG. 14 , asecond muffler cover 170T is disposed above thesecond end plate 160T and asecond muffler chamber 180T is formed between thesecond muffler cover 170T and thesecond end plate 160T. Asecond discharge hole 190T communicating the second compression chamber 133T of thesecond cylinder 121T with thesecond muffler chamber 180T is provided in thesecond end plate 160T near thesecond vane 127T and asecond discharge valve 200T preventing backflow of the compressed cooling medium is provided in thesecond discharge hole 190T. - Furthermore, a second discharge
valve holding member 201T as well as thesecond discharge valve 200T is fixed by a rivet so as to restrict a deflection opening amount of thesecond discharge valve 200T. Thesecond muffler chamber 180T reduces pressure pulsation of the discharged cooling medium. - The
first cylinder 121S, thefirst end plate 160S, thefirst muffler cover 170S, thesecond cylinder 121T, thesecond end plate 160T, thesecond muffler cover 170T, and theintermediate partition plate 140 are integrally fastened by a bolt that is not shown. Among the integrally fastened constituent elements of the compressingsection 12, an outer peripheral portion of thesecond end plate 160T is fixedly bonded to thecompressor housing 10 by spot welding to thereby fix thecompressing section 12 to thecompressor housing 10. - As shown in
FIG. 14 , first and second throughholes cylindrical compressor housing 10 to be axially away from each other in ascending order from a lower portion. Anaccumulator 25T formed of an independent and cylindrical airtight container is arranged outside of thecompressor housing 10 and held by anaccumulator holder 251 and anaccumulator band 253. - A
system connecting pipe 255 connecting theaccumulator 25T to a low-pressure side of a refrigerating cycle is provided in a central portion of a top surface of theaccumulator 25T. First and second connectingpipes accumulator 25T and the other end connected to the other end of first andsecond suction pipes holes 257 provided at a bottom of theaccumulator 25T, respectively. - The first and second connecting
pipes second compressing sections accumulator 25T are connected to first andsecond suction holes second cylinders holes second suction pipes 104, respectively. Namely, the first andsecond suction holes - Discharge portions of the first and
second compressing sections compressor housing 10 via the first andsecond muffler chambers second cylinders second muffler chambers second end plates second discharge valves - A
discharge pipe 107 connected to a high-pressure side of the refrigerating cycle and discharging the high-pressure cooling medium toward the high-pressure side of the refrigerating cycle is connected to a top of thecompressor housing 10. accordingly, the first and second discharge holes 190S and 190T communicate with the high-pressure side of the refrigerating cycle. - The
compressor housing 10 is filled with lubricating oil almost up to a height of thesecond cylinder 121T. The lubricating oil circulates in thecompressing section 12 by a vane pump, not shown, attached to a lower portion of therotary shaft 15 and seals a portion defining the first and second workingchambers - First and second auxiliary discharge holes 190SS and 190TT are provided at positions from the first and
second vane grooves second pistons inner walls auxiliary discharge hole 190A according to the first embodiment since the twocylinders - In the
rotary compressor 3 according to the third embodiment, the first and second auxiliary discharge holes 190SS and 190TT are provided in the first andsecond end plates second compressing sections - Operation of the
rotary compressor 3 described so far will next be described. If therotary compressor 3 is actuated, the cooling medium flowing from the low-pressure side of the refrigerating cycle into theaccumulator 25T through thesystem connecting pipe 255 is separated into a liquid cooling medium and a gas cooling medium. Specifically, the liquid cooling medium is accumulated in a lower portion of theaccumulator 25T and the gas cooling medium is accumulated in an upper portion thereof. - When the first and
second pistons second cylinders second suction chambers accumulator 25T is absorbed into the first andsecond suction chambers second compressing sections pipes second suction pipes 104, and the first andsecond suction holes second pistons second suction chambers second suction holes - If the pressure of the compressed cooling medium in each of the first and second compression chambers 133S and 133T becomes equal to the pressure of each of the first and
second muffler chambers second discharge valves second discharge hole second discharge valves second muffler chambers first muffler chamber 180S. The cooling medium is discharged, as a high-pressure cooling medium, into thecompressor housing 10. Thereafter, the high-pressure cooling medium is fed to an upper portion of themotor 11 through a core notch, not shown, of thestator 111 of themotor 11 and gaps between a core and a coil and discharged toward the high-pressure side of the refrigerating cycle through thedischarge pipe 107. - In the
rotary compressor 3 according to the third embodiment, the cooling medium is discharged into thecompressor housing 10 through the first and second discharge holes 190S and 190T and the first and second auxiliary discharge holes 190SS and 190TT at the low flow resistance. Therefore, the over-compression loss can be reduced. -
FIG. 16 is a top view of a compressing section of a rotary compressor according to a fourth embodiment of the present invention.FIG. 17 is a top view of the compressing section of the rotary compressor according to the first embodiment for reference. As shown inFIG. 16 , in the rotary compressor according to the fourth embodiment, adischarge groove 124 communicating with adischarge hole 190 is provided in a region of a cylinderinner wall 123 corresponding to a position of thedischarge hole 190 provided in oneend plate 160A but no discharge groove is provided in a region of the cylinderinner wall 123 corresponding to a position of anauxiliary discharge hole 190A. - If a
discharge groove 124A is provided in the region of the cylinderinner wall 123 corresponding to the position of theauxiliary discharge hole 190A similarly to therotary compressor 1 according to the first embodiment shown inFIG. 1 , the cooling medium compressed in thecompression chamber 133 leaks into thesuction chamber 131 through narrow gaps between corners of thedischarge groove 124A and thepiston 125 when theeccentric section 152 of thepiston 125 passes through the position of thedischarge groove 124A. - As shown in the rotary compressor according to the fourth embodiment, if a center of the
auxiliary discharge hole 190A is located inward of the cylinderinner wall 123 and no discharge groove is provided in the region of the cylinderinner wall 123 corresponding to the position of theauxiliary discharge hole 190A, the cooling medium leaking from thecompression chamber 133 into thesuction chamber 131 can be reduced. Accordingly, efficiency can be improved, as compared with the case in which thedischarge groove 124 is provided. - In the rotary compressor according to an embodiment of the present invention, the auxiliary discharge hole different from the discharge hole is provided in one end plate in which the discharge hole is provided to increase a total area of the discharge hole. Therefore, there is no need to work a concave portion for the discharge hole, the valve seat around the discharge hole, and the discharge valve to be provided on each of both end plates. It is thereby possible to reduce working cost.
- Although the invention has been described with respect to a specific embodiment for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art that fairly fall within the basic teaching herein set forth.
Claims (8)
1. A rotary compressor comprising:
a compressing section including
a cylindrical cylinder,
two end plates closing both ends of the cylinder, respectively,
a piston held by an eccentric section of a rotary shaft driven to rotate by a motor, and revolving in the cylinder along a cylinder inner wall of the cylinder, a working chamber being formed between the piston and the cylinder inner wall, and
a vane protruding from within a vane groove of the cylinder into the working chamber, abutting on the piston, and dividing the working chamber into a suction chamber and a compression chamber;
an airtight compressor housing accommodating therein the compressing section;
a suction hole provided in the cylinder and communicating the suction chamber with a low-pressure side of a refrigerating cycle; and
a discharge hole provided in one of the end plates and communicating the compression chamber with a high-pressure side of the refrigerating cycle,
wherein an auxiliary discharge hole different from the discharge hole is provided in the one end plate.
2. The rotary compressor according to claim 1 , wherein
discharge valves are provided in the discharge hole and the auxiliary discharge hole, respectively, and
concave portions accommodating therein the discharge valves are separately provided in each of the end plates, respectively.
3. The rotary compressor according to claim 1 , wherein
integrated L-shaped discharge valves are provided in the discharge hole and the auxiliary discharge hole, respectively, and
a concave portion accommodating therein the integrated L-shaped discharge valves and having a fixed portion common to the L-shaped discharge valves is provided in each of the end plates.
4. The rotary compressor according to claim 1 ,
wherein a discharge groove communicating with the discharge hole is provided in a region of the cylinder inner wall corresponding to a position of the discharge hole provided in the one end plate, and no discharge groove is provided in a region of the cylinder inner wall corresponding to a position of the auxiliary discharge hole provided in the one end plate.
5. A rotary compressor comprising:
a low-stage compressing section including
a cylindrical low-stage cylinder,
a low-stage end plate closing one end of the low-stage cylinder,
a low-stage piston held by a low-stage eccentric section of a rotary shaft driven to rotate by a motor and revolving in the low-stage cylinder along a low-stage cylinder inner wall of the low-stage cylinder, a low-stage working chamber being formed between the low-stage piston and the low-stage cylinder inner wall, and
a low-stage vane protruding from within a low-stage vane groove of the low-stage cylinder into the low-stage working chamber, abutting on the low-stage piston, and dividing the low-stage working chamber into a low-stage suction chamber and a low-stage compression chamber;
a high-stage compressing section stacked on the low-stage compressing section via an intermediate partition plate, the high-stage compressing section including
a cylindrical high-stage cylinder,
a high-stage end plate closing one end of the high-stage cylinder,
a high-stage piston held by a high-stage eccentric section of the rotary shaft driven to rotate by the motor, and revolving in the high-stage cylinder along a high-stage cylinder inner wall of the high-stage, a high-stage working chamber being formed between the high-stage piston and the high-stage cylinder inner wall, and
a high-stage vane protruding from within a high-stage vane groove of the high-stage cylinder into the high-stage working chamber, abutting on the high-stage piston, and dividing the high-stage working chamber into a high-stage suction chamber and a high-stage compression chamber;
an airtight compressor housing accommodating therein the low-stage compressing section and the high-stage compressing section;
a low-stage suction hole provided in the low-stage cylinder and communicating the low-stage suction chamber with a low-pressure side of a refrigerating cycle;
a low-stage discharge hole provided in the low-stage end plate and communicating the low-stage compression chamber with a high-stage suction hole provided in the high-stage cylinder; and
a high-stage discharge hole provided in the high-stage end plate and communicating the high-stage compression chamber with a high-pressure side of the refrigerating cycle,
wherein a low-stage auxiliary discharge hole different from the low-stage discharge hole is provided in the low-stage end plate.
6. The rotary compressor according to claim 5 , wherein
discharge valves are provided in the low-stage discharge hole and the low-stage auxiliary discharge hole, respectively, and
concave portions accommodating therein the discharge valves are separately provided in the low-stage end plate, respectively.
7. The rotary compressor according to claim 5 , wherein
integrated L-shaped discharge valves are provided in the low-stage discharge hole and the low-stage auxiliary discharge hole, respectively, and
a concave portion accommodating therein the integrated L-shaped discharge valves and having a fixed portion common to the L-shaped discharge valves is provided in the low-stage end plate.
8. The rotary compressor according to claim 5 ,
wherein a discharge groove communicating with the low-stage discharge hole is provided in a region of the low-stage cylinder inner wall corresponding to a position of the low-stage discharge hole provided in the one end plate, and no discharge groove is provided in a region of the low-stage cylinder inner wall corresponding to a position of the low-stage auxiliary discharge hole provided in the low-stage end plate.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
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JP2008004337A JP2009167828A (en) | 2008-01-11 | 2008-01-11 | Rotary compressor |
JP2008-004337 | 2008-01-11 |
Publications (1)
Publication Number | Publication Date |
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US20090180912A1 true US20090180912A1 (en) | 2009-07-16 |
Family
ID=40601219
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US12/349,618 Abandoned US20090180912A1 (en) | 2008-01-11 | 2009-01-07 | Rotary compressor |
Country Status (4)
Country | Link |
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US (1) | US20090180912A1 (en) |
EP (1) | EP2078862A2 (en) |
JP (1) | JP2009167828A (en) |
CN (1) | CN101532493A (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
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US20100284847A1 (en) * | 2007-11-13 | 2010-11-11 | Jeong-Min Han | 2 stage rotary compressor |
US20110247622A1 (en) * | 2010-04-07 | 2011-10-13 | Chart Sequal Technologies Inc. | Portable Oxygen Delivery Device |
US20120085118A1 (en) * | 2009-06-11 | 2012-04-12 | Mitsubishi Electric Corporation | Refrigerant compressor and heat pump apparatus |
CN104976128A (en) * | 2015-07-15 | 2015-10-14 | 广东美芝制冷设备有限公司 | Rotary compressor and compression assembly thereof |
US20150377237A1 (en) * | 2014-06-27 | 2015-12-31 | Lg Electronics Inc. | Compressor |
US11384760B2 (en) | 2017-08-24 | 2022-07-12 | Fujitsu General Limited | Rotary compressor for enhancing efficiency and suppressing vibration |
US20230120434A1 (en) * | 2020-03-30 | 2023-04-20 | Fujitsu General Limited | Rotary compressor |
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JP5828075B2 (en) * | 2010-04-28 | 2015-12-02 | パナソニックIpマネジメント株式会社 | Rotary compressor |
EP2565460B1 (en) * | 2010-04-28 | 2019-06-26 | Panasonic Corporation | Rotary compressor |
JP5809852B2 (en) * | 2011-06-08 | 2015-11-11 | 東芝キヤリア株式会社 | Rotary compressor and refrigeration cycle apparatus |
CN104514722B (en) * | 2014-12-22 | 2017-01-18 | 重庆凌达压缩机有限公司 | Compressing assembly and rotary compressor with same |
CN104989645B (en) * | 2015-07-13 | 2017-04-12 | 同济大学 | Multiple-exhaust-pressure rolling rotor type compressor |
CN105927543A (en) * | 2016-06-29 | 2016-09-07 | 珠海凌达压缩机有限公司 | Upper flange of compressor and compressor comprising upper flange |
JP2019132254A (en) * | 2018-02-02 | 2019-08-08 | 東芝キヤリア株式会社 | Rotary compressor and refrigeration cycle device |
CN108533490A (en) | 2018-06-22 | 2018-09-14 | 珠海格力电器股份有限公司 | Compressor and air-conditioning system |
CN114017333B (en) * | 2021-11-08 | 2023-07-25 | 广东美芝制冷设备有限公司 | Rotary compressor and refrigeration equipment with same |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4137022A (en) * | 1976-06-02 | 1979-01-30 | Lassota Marek J | Rotary compressor and process of compressing compressible fluids |
US6974314B2 (en) * | 2001-11-30 | 2005-12-13 | Sanyo Electric Co., Ltd. | Rotary compressor, method for manufacturing the same, and defroster for refrigerant circuit |
US20060168996A1 (en) * | 2005-01-31 | 2006-08-03 | Sanyo Electric Co., Ltd. | Refrigerating device, refrigerator, compressor, and gas-liguid separator |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS56175594U (en) | 1980-05-30 | 1981-12-24 | ||
JPS63272988A (en) | 1987-04-30 | 1988-11-10 | Toshiba Corp | Two stage compression type compressor |
JP2006275035A (en) | 2005-03-30 | 2006-10-12 | Sanyo Electric Co Ltd | Refrigerating device, refrigerator and compressor |
-
2008
- 2008-01-11 JP JP2008004337A patent/JP2009167828A/en active Pending
-
2009
- 2009-01-07 US US12/349,618 patent/US20090180912A1/en not_active Abandoned
- 2009-01-09 CN CN200910001529A patent/CN101532493A/en active Pending
- 2009-01-09 EP EP09150282A patent/EP2078862A2/en not_active Withdrawn
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4137022A (en) * | 1976-06-02 | 1979-01-30 | Lassota Marek J | Rotary compressor and process of compressing compressible fluids |
US6974314B2 (en) * | 2001-11-30 | 2005-12-13 | Sanyo Electric Co., Ltd. | Rotary compressor, method for manufacturing the same, and defroster for refrigerant circuit |
US20060168996A1 (en) * | 2005-01-31 | 2006-08-03 | Sanyo Electric Co., Ltd. | Refrigerating device, refrigerator, compressor, and gas-liguid separator |
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20100284847A1 (en) * | 2007-11-13 | 2010-11-11 | Jeong-Min Han | 2 stage rotary compressor |
US8790097B2 (en) * | 2009-06-11 | 2014-07-29 | Mitsubishi Electric Corporation | Refrigerant compressor and heat pump apparatus |
US9011121B2 (en) | 2009-06-11 | 2015-04-21 | Mitsubishi Electric Corporation | Refrigerant compressor and heat pump apparatus |
US20120085118A1 (en) * | 2009-06-11 | 2012-04-12 | Mitsubishi Electric Corporation | Refrigerant compressor and heat pump apparatus |
US9974918B2 (en) | 2010-04-07 | 2018-05-22 | Caire Inc. | Portable oxygen delivery device |
US20110247621A1 (en) * | 2010-04-07 | 2011-10-13 | Chart Sequal Technologies Inc. | Portable Oxygen Delivery Device |
US9974920B2 (en) * | 2010-04-07 | 2018-05-22 | Caire Inc. | Portable oxygen delivery device |
US20110247622A1 (en) * | 2010-04-07 | 2011-10-13 | Chart Sequal Technologies Inc. | Portable Oxygen Delivery Device |
US9974919B2 (en) * | 2010-04-07 | 2018-05-22 | Caire Inc. | Portable oxygen delivery device |
US20150377237A1 (en) * | 2014-06-27 | 2015-12-31 | Lg Electronics Inc. | Compressor |
US10012232B2 (en) * | 2014-06-27 | 2018-07-03 | Lg Electronics Inc. | Compressor |
CN104976128A (en) * | 2015-07-15 | 2015-10-14 | 广东美芝制冷设备有限公司 | Rotary compressor and compression assembly thereof |
US11384760B2 (en) | 2017-08-24 | 2022-07-12 | Fujitsu General Limited | Rotary compressor for enhancing efficiency and suppressing vibration |
US20230120434A1 (en) * | 2020-03-30 | 2023-04-20 | Fujitsu General Limited | Rotary compressor |
US11933302B2 (en) * | 2020-03-30 | 2024-03-19 | Fujitsu General Limited | Rotary compressor |
Also Published As
Publication number | Publication date |
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CN101532493A (en) | 2009-09-16 |
EP2078862A2 (en) | 2009-07-15 |
JP2009167828A (en) | 2009-07-30 |
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