JP2013076337A - Rotary compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary compressor having improved compression efficiency and COP by reducing overcompression loss.SOLUTION: The rotary compressor includes a compression part which includes an annular cylinder having radial suction holes and vane grooves in the lateral side, end plates closing the ends of the cylinder, an annular piston fitted to the eccentric part of a rotating shaft to be rotationally driven by a motor for revolving in the cylinder along the cylinder inner wall of the cylinder to form a working chamber between the cylinder inner wall and itself, and vanes protruded from inside the vane grooves of the cylinder into the working chamber until abutting on the annular piston to partition the working chamber into a suction chamber and a compression chamber. The end plates have discharge holes near the vane grooves in communication with the compression chamber, and the discharge holes of the end plates have recessed parts at the sides of the vane grooves for releasing compressed refrigerant gas from the compression chamber into the discharge holes, respectively.

Description

  The present invention relates to a rotary compressor used in a refrigeration cycle of an air conditioner.

  The rotary compressor is fitted into an annular cylinder having suction holes and vane grooves formed radially on the side, an end plate that closes the end of the cylinder, and an eccentric part of a rotating shaft that is rotated by a motor. An annular piston that revolves along the cylinder inner wall of the cylinder and forms a working chamber with the cylinder inner wall, and protrudes from the vane groove provided in the cylinder into the working chamber and comes into contact with the annular piston. And a vane partitioning the suction chamber and the compression chamber, and a discharge hole for discharging the compressed refrigerant in the compression chamber to the outside of the compression chamber is provided in the vicinity of the vane groove of the end plate. In the rotary compressor having the above structure, after the annular piston revolves in the cylinder and passes through the discharge hole, the refrigerant gas that is not discharged from the discharge port in the small space surrounded by the cylinder inner wall, the annular piston, and the vane is generated. There is a problem that the compression causes an overcompression loss, the compression efficiency decreases, and the COP deteriorates.

  2. Description of the Related Art Conventionally, an airtight container and an electric element and a compression element accommodated in the airtight container are provided, and the compression element has a cylinder having a working chamber inside thereof, and a roller ( An annular piston), a vane that slides in a guide groove provided in the cylinder in contact with the roller and divides the working chamber of the cylinder into a compression chamber and a suction chamber; and a frame body that seals the working chamber of the cylinder ( In the hermetic compressor (rotary compressor) in which the frame body is provided with a discharge hole communicating with the compression chamber of the cylinder, the discharge hole is completely formed in the compression chamber of the cylinder. In the shape of a circle, a long hole, or a three-month shape that does not protrude from the inner peripheral edge of the roller, and the roller has a cylindrical shape or a thick end surface on the discharge hole side. Circle Hermetic compressor which is in the form has been disclosed (e.g., see Patent Document 1).

Further, an electric motor part and a rotary compression mechanism part connected to the electric motor part via a rotary shaft are accommodated in a sealed case, and the rotary compression mechanism part includes a cylinder forming a cylinder chamber, In a hermetic rotary compressor including first and second lid members provided on both end surfaces and covering the cylinder chamber, and a roller and a vane for separating the cylinder chamber into a compression chamber and a suction chamber. At least one of the first and second lid members is provided with a discharge hole for discharging the refrigerant compressed in the cylinder chamber, and the discharge hole is defined as a cross-sectional area of the compression chamber when the vane is located at the bottom dead center. When B (m ² ) and the cross-sectional area of the discharge hole are C (m ² ), C / B ≦ 0.15 is set, and the length of the discharge hole is set to 3 mm or less. Percentage of the area where the hole faces the cylinder chamber Discloses a hermetic rotary compressor in which the above-described cylinder is not provided with a cutout groove for refrigerant discharge (see, for example, Patent Document 2).

JP 05-133363 A JP 2007-198319 A

  However, according to the conventional technique disclosed in Patent Document 1, the discharge port is located completely inside the compression chamber of the cylinder, and the discharge notch is not provided in the compression chamber of the cylinder, thereby reducing reexpansion loss. However, after the roller passes through the discharge hole, in the space surrounded by the inner wall of the cylinder, the roller and the vane, the refrigerant gas that is not discharged is compressed, resulting in an overcompression loss, and the compression efficiency decreases and COP deteriorates. There is a problem that.

  Further, according to the conventional technique disclosed in Patent Document 2, since the ratio of the area where the discharge hole faces the cylinder chamber is set to 87% or more of the cross-sectional area of the discharge hole, it is more than that disclosed in Patent Document 1. After the roller passes through the discharge hole, the volume of the space surrounded by the inner wall of the cylinder, the roller and the vane is reduced, and the overcompression loss is slightly reduced, but the compression efficiency is still lowered and the COP is deteriorated.

  This invention is made | formed in view of the above, Comprising: It aims at obtaining the rotary compressor which reduced the overcompression loss, improved the compression efficiency, and improved COP.

  In order to solve the above-described problems and achieve the object, the present invention provides an annular cylinder having suction holes and vane grooves provided radially on the side, an end plate closing the end of the cylinder, and a motor. An annular piston that is fitted to an eccentric portion of a rotating shaft that is driven by rotation and revolves along the cylinder inner wall of the cylinder and forms an operating chamber between the cylinder inner wall and the cylinder. A rotary compressor having a compression section comprising a vane that protrudes from the vane groove into the working chamber and abuts against the annular piston and divides the working chamber into a suction chamber and a compression chamber. A discharge hole communicating with the compression chamber is provided in the vicinity of the vane groove, and a recess for allowing the compressed refrigerant gas in the compression chamber to escape to the discharge hole is provided on the vane groove side of the discharge hole of the end plate. Be

  According to the present invention, it is possible to obtain a rotary compressor with a small overcompression loss, high compression efficiency, and high COP.

FIG. 1 is a longitudinal sectional view showing an embodiment of a rotary compressor according to the present invention. FIG. 2 is a cross-sectional view illustrating the first and second compression units of the first embodiment. FIG. 3 is an enlarged view of a portion A in FIG. FIG. 4 is a bottom view showing the upper end plate of the first embodiment. FIG. 5 is a cross-sectional view illustrating the first and second compression units of the second embodiment. FIG. 6 is an enlarged view of a portion B in FIG.

  Embodiments of a rotary compressor according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

  FIG. 1 is a longitudinal sectional view showing an embodiment of a rotary compressor according to the present invention, FIG. 2 is a transverse sectional view showing first and second compression portions of Embodiment 1, and FIG. FIG. 4 is an enlarged view of a portion A in FIG. 2, and FIG. 4 is a bottom view showing the upper end plate of the first embodiment.

  As illustrated in FIG. 1, the rotary compressor 1 according to the first embodiment includes a compression unit 12 disposed at a lower portion of a sealed vertical cylindrical compressor housing 10 and an upper portion of the compressor housing 10. And a motor 11 that drives the compression unit 12 via the rotating shaft 15.

  The stator 111 of the motor 11 is fixed by being shrink-fitted on the inner peripheral surface of the compressor housing 10. The rotor 112 of the motor 11 is disposed at the center of the stator 111 and is fixed by being shrink-fitted to a rotating shaft 15 that mechanically connects the motor 11 and the compression unit 12.

  The compression unit 12 includes a first compression unit 12S and a second compression unit 12T that is installed in parallel with the first compression unit 12S and stacked on the upper side of the first compression unit 12S. As shown in FIG. 2, the first and second compression parts 12S and 12T are provided with first and second suction holes 135S and 135T, and first and second vane grooves 128S and 128T radially on the side parts. Annular first and second cylinders 121S and 121T are provided.

  As shown in FIG. 2, circular first and second cylinder inner walls 123 </ b> S and 123 </ b> T are formed in the first and second cylinders 121 </ b> S and 121 </ b> T concentrically with the rotating shaft 15 of the motor 11. In the first and second cylinder inner walls 123S and 123T, first and second annular pistons 125S and 125T having an outer diameter smaller than the cylinder inner diameter are arranged, respectively, and the first and second cylinder inner walls 123S and 123T, The first and second working chambers 130S and 130T are formed between the first and second annular pistons 125S and 125T for sucking, compressing and discharging the refrigerant gas.

  First and second vane grooves 128S and 128T are formed in the first and second cylinders 121S and 121T in the radial direction from the first and second cylinder inner walls 123S and 123T over the entire cylinder height. Flat plate-like first and second vanes 127S and 127T are slidably fitted into the second vane grooves 128S and 128T, respectively.

  As shown in FIG. 2, the first and second vane grooves 128S and 128T are communicated with the first and second vane grooves 128S and 128T from the outer periphery of the first and second cylinders 121S and 121T at the back of the first and second vane grooves 128S and 128T. First and second spring holes 124S and 124T are formed. Vane springs (not shown) that press the back surfaces of the first and second vanes 127S and 127T are inserted into the first and second spring holes 124S and 124T. When the rotary compressor 1 is started, the first and second vanes 127S and 127T are moved from the first and second vane grooves 128S and 128T to the first and second working chambers 130S and 130T by the repulsive force of the vane springs. The first and second working chambers 130S and 130T are moved to the first and second working chambers 130S and 130T by the first and second vanes 127S and 127T, respectively. The second suction chambers 131S and 131T and the first and second compression chambers 133S and 133T (the volume is substantially zero in FIG. 2).

  In addition, the first and second cylinders 121S and 121T communicate with the inner portions of the first and second vane grooves 128S and 128T and the interior of the compressor housing 10 through the opening R shown in FIG. First and second pressure introducing passages 129S and 129T are formed in which the compressed refrigerant gas in the housing 10 is introduced and back pressure is applied to the first and second vanes 127S and 127T by the pressure of the refrigerant gas. .

  In the first and second cylinders 121S and 121T, the first and second suction chambers 131S and 131T communicate with the outside in order to suck the refrigerant from the outside into the first and second suction chambers 131S and 131T. Second suction holes 135S and 135T are provided.

  Further, as shown in FIG. 1, an intermediate partition plate 140 is disposed between the first cylinder 121S and the second cylinder 121T, and the second operation of the first working chamber 130S of the first cylinder 121S and the second cylinder 121T. The room 130T is partitioned. A lower end plate 160S is installed at the lower end of the first cylinder 121S, and closes the first working chamber 130S of the first cylinder 121S. An upper end plate 160T is installed at the upper end of the second cylinder 121T, and closes the second working chamber 130T of the second cylinder 121T.

  A lower bearing portion 161S is formed on the lower end plate 160S, and the lower bearing support portion 151 of the rotary shaft 15 is rotatably supported by the lower bearing portion 161S. An upper bearing portion 161T is formed on the upper end plate 160T, and an upper bearing support portion 153 of the rotary shaft 15 is rotatably supported by the upper bearing portion 161T.

  The rotating shaft 15 includes a first eccentric portion 152S and a second eccentric portion 152T that are offset by 180 ° from each other. The first eccentric portion 152S is a first annular portion of the first compression portion 12S. The second eccentric portion 152T is rotatably fitted to the second annular piston 125T of the second compression portion 12T.

  When the rotary shaft 15 rotates, the first and second annular pistons 125S and 125T move in the first and second cylinders 121S and 121T counterclockwise in FIG. 2 along the first and second cylinder inner walls 123S and 123T. Revolving and following this, the first and second vanes 127S and 127T reciprocate. Due to the movement of the first and second annular pistons 125S and 125T and the first and second vanes 127S and 127T, the volumes of the first and second suction chambers 131S and 131T and the first and second compression chambers 133S and 133T are continuous. The compressor 12 continuously sucks, compresses and discharges the refrigerant gas.

  As shown in FIG. 1, a lower muffler cover 170S is arranged below the lower end plate 160S, and a lower muffler chamber 180S is formed between the lower end plate 160S and the lower muffler cover 170S. And the 1st compression part 12S is opened to lower muffler room 180S. That is, a first discharge hole 190S (see FIG. 2) that connects the first compression chamber 133S of the first cylinder 121S and the lower muffler chamber 180S is provided in the vicinity of the first vane 127S of the lower end plate 160S. A first discharge valve 200S that prevents the backflow of the compressed refrigerant gas is disposed in the hole 190S. Details of the first discharge hole 190S will be described later.

  The lower muffler chamber 180S is one chamber formed in an annular shape, and the lower end plate 160S, the first cylinder 121S, the intermediate partition plate 140, the second cylinder 121T, and the upper end plate 160T are arranged on the discharge side of the first compression unit 12S. This is a part of the communication passage that communicates with the upper muffler chamber 180T through the refrigerant passage 136 (see FIG. 2) that passes through the upper muffler chamber. The lower muffler chamber 180S reduces the pressure pulsation of the discharged refrigerant gas. In addition, a first discharge valve presser 201S for limiting the amount of flexure opening of the first discharge valve 200S is fixed to the first discharge valve 200S together with the first discharge valve 200S by a rivet.

  As shown in FIG. 1, an upper muffler cover 170T is installed above the upper end plate 160T, and an upper muffler chamber 180T is formed between the upper end plate 160T and the upper muffler cover 170T. In the vicinity of the second vane 127T of the upper end plate 160T, a second discharge hole 190T (see FIG. 2) that communicates the second compression chamber 133T of the second cylinder 121T and the upper muffler chamber 180T is provided, and the second discharge hole 190T. Is provided with a second discharge valve 200T for preventing the backflow of the compressed refrigerant gas. In addition, a second discharge valve presser 201T for limiting the deflection opening amount of the second discharge valve 200T is fixed to the second discharge valve 200T by a rivet together with the second discharge valve 200T. The upper muffler chamber 180T reduces the pressure pulsation of the discharged refrigerant. Details of the second discharge hole 190T will be described later.

  The first cylinder 121S, the lower end plate 160S, the lower muffler cover 170S, the second cylinder 121T, the upper end plate 160T, the upper muffler cover 170T, and the intermediate partition plate 140 are integrally fastened by through bolts 175 or the like. Out of the compression portion 12 that is integrally fastened by a through bolt 175 or the like, the outer peripheral portion of the upper end plate 160T is fixed to the compressor housing 10 by spot welding, and the compression portion 12 is fixed to the compressor housing 10. .

  The first and second through holes 101 and 102 are passed through the outer peripheral wall of the cylindrical compressor housing 10 in order from the lower part in the axial direction so as to pass the first and second suction pipes 104 and 105. Is provided. In addition, an accumulator 25 formed of an independent cylindrical sealed container is held by an accumulator holder 252 and an accumulator band 253 on the outer side of the compressor housing 10.

  A system connection tube 255 connected to the refrigeration cycle is connected to the center of the top of the accumulator 25, and one end of the bottom through hole 257 provided at the bottom of the accumulator 25 extends to the upper part inside the accumulator 25. The first and second low-pressure communication pipes 31S and 31T whose ends are connected to the other ends of the first and second suction pipes 104 and 105 are connected.

  The first and second low-pressure connecting pipes 31S and 31T that guide the low-pressure refrigerant of the refrigeration cycle to the first and second compression parts 12S and 12T through the accumulator 25 are the first and second suction pipes 104, The first and second cylinders 121S and 121T are connected to the first and second suction holes 135S and 135T (see FIG. 2) via the 105. That is, the first and second suction holes 135S and 135T communicate with the refrigeration cycle in parallel.

  A discharge pipe 107 is connected to the top of the compressor housing 10 as a discharge unit that is connected to the refrigeration cycle and discharges high-pressure refrigerant gas to the refrigeration cycle. That is, the first and second discharge holes 190S and 190T communicate with the refrigeration cycle.

  Lubricating oil is sealed in the compressor housing 10 up to the height of the second cylinder 121T. Further, the lubricating oil circulates in the compression section 12 by a blade pump (not shown) inserted in the lower part of the rotating shaft 15, and the compression space of the compressed refrigerant is partitioned by lubrication of sliding parts and a minute gap Have a seal.

  Next, a characteristic configuration of the rotary compressor 1 according to the first embodiment will be described with reference to FIGS. In the vicinity of the first and second vane grooves 128S and 128T on the first and second compression chambers 133S and 133T (see FIG. 2) side of the lower end plate 160S and the upper end plate 160T, the first and second compression chambers 133S, First and second discharge holes 190S and 190T communicating with 133T are provided.

  In the rotary compressor 1 of the first embodiment, the first and second discharge holes 190S and 190T are completely disposed inside the first and second cylinder inner walls 123S and 123T. The first and second discharge holes 190S and 190T have circular outlines, the first and second cylinder inner walls 123S and 123T, and the first and second compression chambers 133S of the first and second vane grooves 128S and 128T. It is arranged so as to be in contact with the extension lines 128Sa and 128Ta of the wall surface on the 133T side.

  The lower end plate 160S and the upper end plate 160T have first and second vane grooves 128S and 190T side contour lines of the first and second discharge holes 190S and 190T, and first and second cylinder inner walls 123S and 123T. And extension lines 128Sa and 128Ta on the wall surfaces of the first and second vane grooves 128S and 128T on the first and second compression chambers 133S and 133T sides, respectively (this line is the contour line and the extension line). Are formed in a substantially triangular shape with a depth of 1 to 2 mm and surrounded by recesses 190Sa and 190Ta. In the first embodiment, the recesses 190Sa and 190Ta are formed on both the lower end plate 160S and the upper end plate 160T. However, the recess 190Sa or 190Ta may be formed only on either the lower end plate 160S or the upper end plate 160T. Good. As the material of the lower end plate 160S and the upper end plate 160T, it is desirable to use a sintered alloy material in terms of lubricity and workability.

  In the recesses 190Sa and 190Ta, the first and second annular pistons 125S and 125T revolve counterclockwise, and the contact points between the first and second annular pistons 125S and 125T and the first and second cylinder inner walls 123S and 123T are the first. The first and second compression chambers 133S and 133T come close to the second vane grooves 128S and 128T and the first and second annular pistons 125S and 125T completely block the first and second discharge holes 190S and 190T. Is communicated with the first and second discharge holes 190S and 190T, and the compressed refrigerant gas in the first and second compression chambers 133S and 133T is released to the first and second discharge holes 190S and 190T, thereby preventing refrigerant over-compression. , Reduce over-compression loss, improve compression efficiency and improve COP.

  Next, a characteristic configuration of the rotary compressor 1 according to the second embodiment will be described with reference to FIGS. 5 and 6. FIG. 5 is a cross-sectional view showing the first and second compression portions of the second embodiment, and FIG. 6 is an enlarged view of a portion B in FIG. In the vicinity of the first and second vane grooves 128S and 128T on the first and second compression chambers 133S and 133T (see FIG. 5) side of the lower end plate 160S and the upper end plate 160T (see FIG. 1), First and second discharge holes 192S and 192T communicating with the two compression chambers 133S and 133T are provided.

  In the rotary compressor 1 of the second embodiment, a part of the first and second discharge holes 192S and 192T is disposed outside the first and second cylinder inner walls 123S and 123T. The first and second discharge holes 192S and 192T have circular outlines in contact with the extension lines 128Sa and 128Ta of the wall surfaces of the first and second vane grooves 128S and 128T on the first and second compression chambers 133S and 133T side. Are arranged as follows.

  In the lower end plate 160S and the upper end plate 160T, the first and second vane grooves 128S and 128T side contour lines of the first and second discharge holes 192S and 192T, and the first and second vane grooves 128S and 128T of the first line. The tangent between the corner of the wall on the second compression chamber 133S, 133T side and the outer contour of the first and second cylinder inner walls 123S, 123T of the first and second discharge holes 192S, 192T, and the first, first Lines extending along the extension lines 128Sa and 128Ta of the wall surfaces of the two vane grooves 128S and 128T on the first and second compression chambers 133S and 133T side (this line is slightly deviated from the contour line, tangential line, and extension line). The recesses 192Sa and 192Ta having a depth of 1 to 2 mm and surrounded by a circle may be formed (only one of the recesses 192Sa or 192Ta may be used). Discharge notches 123Sa and 123Ta are provided in portions of the first and second cylinder inner walls 123S and 123T that overlap the first and second discharge holes 192S and 192T.

  In the recesses 192Sa and 192Ta, the first and second annular pistons 125S and 125T revolve counterclockwise, and the contact points between the first and second annular pistons 125S and 125T and the first and second cylinder inner walls 123S and 123T are the first. The first and second compression chambers 133S, after approaching the second vane grooves 128S and 128T, passing through the discharge notches 123Sa and 123Ta and completely closing the first and second discharge holes 192S and 192T, 133T is communicated with the first and second discharge holes 192S and 192T, the compressed refrigerant gas in the first and second compression chambers 133S and 133T is released to the first and second discharge holes 192S and 192T, and the refrigerant is over-compressed. Prevent, reduce over-compression loss, improve compression efficiency and improve COP.

  In addition, although Example 1 and 2 demonstrated the Example of the 2 cylinder type rotary compressor, the rotary compressor of this invention is applied also to a single cylinder type rotary compressor and a 2 stage | paragraph compression type rotary compressor. Can do.

DESCRIPTION OF SYMBOLS 1 Rotary compressor 10 Compressor housing | casing 11 Motor 12 Compression part 15 Rotating shaft 25 Accumulator 31S 1st low pressure connection pipe 31T 2nd low pressure connection pipe 101 1st through-hole 102 2nd through-hole 104 1st suction pipe 105 2nd suction | inhalation Pipe 107 Discharge pipe (discharge part)
111 Stator 112 Rotor 12S First Compression Unit 12T Second Compression Unit 121S First Cylinder (Cylinder)
121T 2nd cylinder (cylinder)
123S 1st cylinder inner wall (cylinder inner wall)
123Sa Discharge notch 123T Second cylinder inner wall (cylinder inner wall)
123Ta Discharge cutout portion 124S First spring hole 124T Second spring hole 125S First annular piston (annular piston)
125T second annular piston (annular piston)
127S 1st vane (vane)
127T 2nd vane (vane)
128S 1st vane groove (vane groove)
128T 2nd vane groove (vane groove)
129S first pressure introduction path 129T second pressure introduction path 130S first working chamber (working chamber)
130T second working chamber (working chamber)
131S First suction chamber (suction chamber)
131T Second suction chamber (suction chamber)
133S 1st compression chamber (compression chamber)
133T Second compression chamber (compression chamber)
135S 1st suction hole (suction hole)
135T 2nd suction hole (suction hole)
136 Refrigerant passage 140 Intermediate partition plate 151 Lower bearing support portion 152S First eccentric portion (eccentric portion)
152T second eccentric part (eccentric part)
153 Upper bearing support 160S Lower end plate (end plate)
160T Top plate (end plate)
161S Lower bearing portion 161T Upper bearing portion 170S Lower muffler cover 170T Upper muffler cover 175 Through bolt 180S Lower muffler chamber 180T Upper muffler chamber 190S, 192S First discharge hole (discharge hole)
190Sa, 192Sa Concavity 190T, 192T Second discharge hole (discharge hole)
190Ta, 192Ta Concave part 200S 1st discharge valve 200T 2nd discharge valve 201S 1st discharge valve holder 201T 2nd discharge valve holder 252 Accum holder 253 Accum band 255 System connection pipe R Opening part of 1st, 2nd pressure introduction path

Claims (4)

An annular cylinder provided with suction holes and vane grooves radially on the side,
An end plate for closing the end of the cylinder;
An annular piston that is fitted to an eccentric portion of a rotating shaft that is driven to rotate by a motor, revolves along the cylinder inner wall of the cylinder, and forms an operation chamber between the cylinder inner wall;
A vane that protrudes from the vane groove provided in the cylinder into the working chamber and abuts against the annular piston and divides the working chamber into a suction chamber and a compression chamber;
In a rotary compressor having a compression section comprising:
A discharge hole communicating with the compression chamber is provided near the vane groove of the end plate,
A rotary compressor characterized in that a recess for allowing the compressed refrigerant gas in the compression chamber to escape to the discharge hole is provided on the vane groove side of the discharge hole of the end plate.   The rotary compressor according to claim 1, wherein the discharge hole is disposed completely inside the inner wall of the cylinder.   2. The discharge hole according to claim 1, wherein a part of the discharge hole is disposed outside the inner wall of the cylinder, and a discharge notch is provided in a portion overlapping the discharge hole of the inner wall of the cylinder. Rotary compressor. The rotary compressor according to any one of claims 1 to 3, wherein the rotary compressor is a two-cylinder type or a two-stage compression type.

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