JP2009115067A - Two-stage compression rotary compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a low-cost two-stage compression rotary compressor improving mechanical efficiency by suppressing sliding loss of a low-stage vane and a low-stage piston of a low-stage compression part, reducing wear amount of the low-stage vane and low-stage piston and having simple structure. <P>SOLUTION: The two-stage compression rotary compressor is provided with the low-stage compression part, a high-stage compression part laminated on the low-stage compression part via an intermediate partition wall, a sealed compressor casing storing the low-stage compression part and high-stage compression part, and back pressure introduction passages for communicating inside of the compressor casing with back parts of a low-stage vane groove and high-stage vane groove. The thickness of the low-stage vane and low-stage vane groove is set thinner than that of the high-stage vane and high-stage vane groove. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a two-stage compression rotary compressor (hereinafter also simply referred to as “rotary compressor”) used in a refrigeration cycle of an air conditioner.

  The two-stage compression rotary compressor has a low-stage compression section and a high-stage compression section, and a low-stage and a high-stage compression section with a low-stage and a high-stage piston inside a cylindrical compressor housing that is a sealed container. A motor driven by a stage and a high stage eccentric part, and an accumulator on the outer side of the compressor housing.

  Conventionally, a motor is housed in an upper part of a hermetic compressor housing, and a rotary shaft driven by the motor and having two eccentric parts, an upper bearing part supporting the rotary shaft at the lower part of the motor, and an intermediate partition plate In the two-stage compression rotary compressor, comprising: a compression section in which a low-stage compression section and a high-stage compression section are stacked in layers; and a lower bearing section that supports a rotating shaft at a lower portion of the compression section. Each of the compression section and the high-stage compression section includes a cylindrical cylinder, a cylindrical piston that rotates eccentrically along the inner wall of the cylinder, and a flat plate that partitions a space formed by the outer periphery of the piston and the inner wall of the cylinder. In which the angle θ1 from the vane of the low-stage compression portion to the position where the clearance between the inner wall of the cylinder and the outer periphery of the piston is minimized is set to 150 ° to 210 °. Is (e.g. See Patent Document 1).

JP 2005-127167 A

However, according to the above conventional technique, in the case of a high-pressure compressor inside the compressor housing, in the high stage side compression portion, the force F (H) that the tip of the vane is pressed against the outer peripheral portion of the piston, and low The force F (L) by which the tip of the vane is pressed against the outer peripheral portion of the piston in the stage side compression portion is neglected by the force of the vane spring that presses the vane in an auxiliary manner, and the compression chamber volume of the two-stage compression rotary compressor in FIG. And the compression chamber pressure and the pressure applied to the vanes of the low-stage compression section and the high-stage compression section in FIG. The pressure is Pd (H), the high-stage suction chamber pressure is Ps (H), the high-stage compression chamber pressure is Pc (H), the low-stage suction chamber pressure is Ps (L), and the low-stage suction chamber pressure is Ps (H). Side compression chamber pressure is Pc (L), vane height is h, vane thickness t, the thickness of the suction chamber side from the sealing point of the tip of the vane is in contact with the piston outer peripheral ts, if the seal point to the thickness of the compression chamber side and tc,
F (H) = (Pd (H) × t−Ps (H) × ts−Pc (H) × tc) × h
F (L) = (Pd (H) × t−Ps (L) × ts−Pc (L) × tc) × h
It becomes.

  Here, since Ps (H)> Ps (L) and Pc (H)> Pc (L), F (H) <F (L), that is, in the low-stage compression portion, the tip of the vane is more than necessary. This force pushes against the outer periphery of the piston, increasing the sliding loss and lowering the mechanical efficiency. Furthermore, there is a problem that the wear amount of the tip of the vane and the outer peripheral portion of the piston is increased, and the reliability of the compressor is lowered.

  Further, as a countermeasure to the above problem, there is a so-called compressor casing internal intermediate pressure type compressor in which the inside of the compressor casing is filled with the discharge gas of the low stage compression section. In this case, the back of the high stage vane is used. There is a problem that the pressure chamber needs to be partitioned from the inside of the compressor housing in a pressure manner, and the structure is complicated and the cost is increased.

  The present invention has been made in view of the above, and suppresses the sliding loss between the low-stage vane and the low-stage piston of the low-stage compression portion, improves the mechanical efficiency, reduces the wear amount of both, and An object is to obtain a two-stage compression rotary compressor having a simple structure and low cost.

  In order to solve the above-mentioned problems and achieve the object, the present invention provides a low-stage cylinder that is held by a cylindrical low-stage cylinder and a low-stage eccentric part of a rotary shaft that is driven to rotate by a motor. A low-stage piston that revolves in the low-stage cylinder along the cylinder inner wall and forms a low-stage working chamber with the inner wall of the low-stage cylinder; and the low-stage working chamber from within the low-stage vane groove of the low-stage cylinder A low-stage compression section that includes a low-stage vane that protrudes in contact with the low-stage piston and divides the low-stage working chamber into a low-stage suction chamber and a low-stage compression chamber, and an intermediate partition plate The high stage is laminated along the inner wall of the high stage cylinder, which is stacked on the low stage compression part and is held by a cylindrical high stage cylinder and a high stage eccentric part of a rotary shaft that is driven to rotate by the motor. A high-stage working chamber that revolves inside the cylinder and is between the inner wall of the high-stage cylinder A high-stage piston to be formed, protrudes from the high-stage vane groove of the high-stage cylinder into the high-stage working chamber, contacts the high-stage piston, and the high-stage working chamber becomes a high-stage suction chamber and a high-stage compression chamber. A high-stage compression section comprising a partitioning high-stage vane, a hermetically sealed compressor housing that houses the low-stage compression section and the high-stage compression section, and a low-stage suction communicating with the low-stage suction chamber A low pressure communication pipe that communicates a hole to the low pressure side of the refrigeration cycle, an intermediate communication pipe that communicates a low stage discharge hole that communicates with the low stage compression chamber and a high stage suction hole that communicates with the high stage suction chamber, A discharge pipe for communicating a high-stage discharge hole communicating with the high-stage compression chamber to a high-pressure side of the refrigeration cycle through the compressor housing, the compressor housing, the low-stage vane groove, and the high-stage vane groove A two-stage compression rotary compressor having a back pressure introduction path communicating with the inner part of There are, the thickness of the low-stage vanes and low-stage vane groove, characterized by being thinner than the thickness of the high-stage vanes and the high-stage vane groove.

  In the two-stage compression rotary compressor according to the present invention, the thickness of the low-stage vane of the low-stage compression section is made thinner than the thickness of the high-stage vane of the high-stage compression section, so that the tip of the low-stage vane has a low stage. It is possible to prevent the force pressed against the outer peripheral portion of the piston from becoming larger than necessary, and there are effects that the sliding loss is small, the mechanical efficiency is high, the structure is simple, and the cost is low.

  Also, when trying to reduce the suction pressure loss by enlarging the low stage suction hole of the low stage compression section, the low stage suction hole of the low stage cylinder interferes with the low stage vane groove, and the size of the low stage suction hole is reduced. Although it is restricted, by reducing the thickness of the low stage vane, the width (thickness) of the low stage vane groove can be reduced, and the low stage suction hole can be increased accordingly.

  Below, the Example of the two-stage compression rotary compressor concerning this invention is described in detail based on drawing. 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 of a low stage compression section, and FIG. 3 is a transverse sectional view of a high stage compression section. 4 is a cross-sectional view taken along the line AA in FIG. 1, FIG. 5 is a cross-sectional view of the low-stage end plate, and FIG. 6 is a cross-sectional view taken along the line BB in FIG. FIG.

  As shown in FIG. 1, the rotary compressor 1 according to the embodiment includes a compression unit 12 and a motor 11 that drives the compression unit 12 inside a sealed cylindrical compressor housing 10. .

  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 low-stage compression unit 12L and a high-stage compression unit 12H that is connected in series to the low-stage compression unit 12L and stacked and installed on the upper side of the low-stage compression unit 12L. As shown in FIG. 2, the low-stage compression section 12L includes a short cylindrical low-stage cylinder 121L, and as illustrated in FIG. 3, the high-stage compression section 12H includes a short cylindrical high-stage cylinder 121H. Yes.

  The low-stage cylinder 121L and the high-stage cylinder 121H are formed with cylindrical low-stage and high-stage cylinder inner walls 123L and 123H concentrically with the motor 11, respectively. In the low-stage and high-stage cylinder inner walls 123L and 123H, cylindrical low-stage and high-stage pistons 125L and 125H having an outer diameter smaller than the diameter of the low-stage and high-stage cylinder inner walls are arranged, respectively. Low-stage and high-stage working chambers 132L and 132H (compression spaces) are formed between the stage cylinder inner walls 123L and 123H and the low-stage and high-stage pistons 125L and 125H.

  Low-stage and high-stage cylinders 121L and 121H are formed with low-stage and high-stage vane grooves 128L and 128H extending in the radial direction from the low-stage and high-stage cylinder inner walls 123L and 123H, respectively. Flat low stages and high stage vanes 127L and 127H are fitted in the high stage vane grooves 128L and 128H, respectively.

  In order to make the volume of the high stage working chamber 130H of the high stage compression section 12H smaller than the volume of the low stage working chamber 130L of the low stage compression section 12L, the high stage cylinder 121H, the high stage piston 125H, and the high stage vane 127H are respectively provided. The height in the axial direction is lower than that of the low stage cylinder 121L, the low stage piston 125L, and the low stage vane 127L.

  Although not shown in the drawings, low and high springs are arranged in the back of the low and high vane grooves 128L and 128H. Normally, due to the repulsive force of the low and high stage springs, the low and high stage vanes 127L and 127H are moved from the low stage and high stage vane grooves 128L and 128H into the low and high stage working chambers 130L and 130H. Protruding and its tip abuts the outer peripheral surface of the low-stage and high-stage pistons 125L and 125H, and the low-stage and high-stage vanes 127L and 127H make the low-stage and high-stage working chambers 130L and 130H (compression space) low. The upper and lower suction chambers 131L and 131H are divided into the lower and higher compression chambers 133L and 133H.

  Further, the low-stage and high-stage cylinders 121L and 121H are connected to the low-stage and high-stage vanes 127L and 127H by communicating the inner portions of the low-stage and high-stage vane grooves 128L and 128H with the interior of the compressor housing 10. Back pressure introduction paths 129L and 129H for applying pressure are formed.

As a characteristic configuration of the present invention, the thickness t _L of the low stage vane 127L and the low stage vane groove 128L is made thinner than the thickness t _H of the high stage vane 127H and the high stage vane groove 128H. The thickness t _L of the low stage vane 127L and the low stage vane groove 128H may be 75% to 90% of the thickness t _H of the high stage vane 127H and the high stage vane groove 128H.

In the high-stage compression section, the force F (H) that the tip of the vane is pressed against the outer periphery of the piston, and the force F (L) that the tip of the vane is pressed against the outer periphery of the piston in the low-stage compression section is If the force of the vane spring that presses the vane auxiliary is ignored, the relationship between the compression chamber volume and the compression chamber pressure of the two-stage compression rotary compressor in FIG. 7 and the low-stage compression section and the high-stage compression section in FIG. As shown in the pressure applied to the vane of the compressor, the internal pressure of the compressor casing (pressure in the sealed container), that is, the high-stage side discharge pressure is Pd (H), the high-stage side suction chamber pressure is Ps (H), and the high-stage side pressure is The pressure in the compression chamber is Pc (H), the pressure in the lower suction chamber is Ps (L), the pressure in the lower compression chamber is Pc (L), the vane height is h, and the vane thickness is t, the thickness on the suction chamber side from the seal point where the tip of the vane contacts the piston outer circumference s, when the thickness of the compression chamber side and tc from the sealing point,
F (H) = (Pd (H) × t−Ps (H) × ts−Pc (H) × tc) × h
F (L) = (Pd (H) × t−Ps (L) × ts−Pc (L) × tc) × h
It becomes.

Here, since Ps (H)> Ps (L) and Pc (H)> Pc (L), F (H) <F (L). Accordingly, when the thicknesses t _L and t _H of the low stage and high stage compression parts 12L and 12H are made the same, the low stage compression part 12l has the tip of the low stage vane 127L at the low stage piston 125L with an excessive force. Is pushed against the outer periphery of the cylinder and the sliding loss is increased, the mechanical efficiency is reduced, and the wear amount of the outer end of the low stage vane 127L and the outer stage of the low stage piston 125L is increased, reducing the reliability of the compressor. End up.

In the present invention, as described above, the thickness t _L of the low stage vane 127L and the low stage vane groove 128H is 75% to 90% of the thickness t _H of the high stage vane 127H and the high stage vane groove 128H. In the low-stage compression portion 12L, the tip of the low-stage vane 127L is not pressed against the outer peripheral portion of the low-stage piston 125L with an excessive force.

  Since the differential pressure between the suction pressure and the discharge pressure is smaller in the lower stage, the bending moment acting on the vanes is smaller in the lower stage. Therefore, the lower stage vane 127L is thinner than the higher stage vane 127H. can do.

In general, the maximum pressure difference between the low pressure side and the high pressure side is ½ at the low stage compared to the high stage (in the air conditioner of R410A, the condition that the pressure difference becomes the largest is the highest stage 0. 3MPa → 4.3MPa (differential pressure 4MPa), low stage 1.5MPa → 3.3MPa (differential pressure 1.8MPa)), and the bending deflection of the vane is inversely proportional to the cube of the vane thickness. When the eccentric amount of the portion 152L and the eccentric amount of the high-stage eccentric portion 152H are the same, the thickness of the low-stage vane 127L is (1/2) ^1/3 ≈0 of the thickness of the high-stage vane 127H. .8 is sufficient.

The low-stage and high-stage cylinders 121L and 121H have low-stage and high-stage suction holes communicating with the low-stage and high-stage suction chambers 131L and 131H in order to suck the refrigerant into the low-stage and high-stage suction chambers 131L and 131H. 135L and 135H are provided. If the hole diameter of the low-stage intake hole 135L is made larger than the hole diameter of the high-stage intake hole 135H using the space of the low-stage cylinder inner wall 123L corresponding to the reduced thickness t _L of the low-stage vane groove 128H, the low The refrigerant suction resistance of the stage suction hole 135L can be reduced.

  Further, an intermediate partition plate 140 is installed between the low-stage cylinder 121L and the high-stage cylinder 121H to partition 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. Yes. A low-stage end plate 160L is installed below the low-stage cylinder 121L, and closes the lower part of the low-stage working chamber 130L of the low-stage cylinder 121L. A high stage end plate 160H is installed on the upper side of the high stage cylinder 121H, and closes the upper part of the high stage working chamber 130H of the high stage cylinder 121H.

  A sub-bearing portion 161L is formed on the low-stage end plate 160L, and a sub-bearing support portion 151 of the rotary shaft 15 is rotatably supported on the sub-bearing portion 161L. The high stage end plate 160H is formed with a main bearing portion 161H, and the main bearing support portion 153 of the rotary shaft 15 is rotatably supported by the main bearing portion 161H.

  The rotary shaft 15 includes a low-stage eccentric portion 152L and a high-stage eccentric portion 152H that are eccentric by shifting the phase by 180 °, and the low-stage eccentric portion 152L is a low-stage piston 125L of the low-stage compression portion 12L. The high-stage eccentric part 152H rotatably holds the high-stage piston 125H of the high-stage compression part 12H. The eccentric amount of the low-stage eccentric portion 152L and the eccentric amount of the high-stage eccentric portion 152H are the same.

  When the rotary shaft 15 rotates, the low-stage and high-stage pistons 125L and 125H revolve in the low-stage and high-stage cylinders 121L and 121H along the low-stage and high-stage cylinder inner walls 123L and 123H. The low and high vanes 127L and 127H reciprocate. Due to the movement of the low-stage and high-stage pistons 125L and 125H and the low-stage and high-stage vanes 127L and 127H, the volumes of the low-stage and high-stage suction chambers 131L and 131H and the low-stage and high-stage compression chambers 133L and 133H are continuously increased. The compressor 12 continuously sucks, compresses and discharges the refrigerant.

  A low-stage muffler cover 170L is installed below the low-stage end plate 160L, and a low-stage muffler chamber 180L is formed between the low-stage end plate 160L. And the discharge part of the low stage compression part 12L is opened to the low stage muffler chamber 180L. That is, the low-stage end plate 160L is provided with a low-stage discharge hole 190L that connects the low-stage compression chamber 133L and the low-stage muffler chamber 180L of the low-stage cylinder 121L, and the low-stage discharge hole 190L is compressed. A low-stage discharge valve 200 </ b> L that prevents the refrigerant from flowing backward is installed.

  If the hole diameter of the low-stage discharge hole 190L is made larger than the hole diameter of the high-stage discharge hole 190H described later, the flow resistance of the low-stage compression section 12L having a larger volume flow rate of refrigerant than the high-stage compression section 12H can be reduced. .

  As shown in FIGS. 4 and 5, the low-stage muffler chamber 180L is an annularly communicated chamber, and is an intermediate that communicates the high-pressure side of the low-stage compression unit 12L and the low-pressure side of the high-stage compression unit 12H. It is a part of the communication path. The low stage muffler chamber 180L reduces the pressure pulsation of the discharged refrigerant.

  Further, as shown in FIGS. 5 and 6, a low stage discharge valve presser 201L for limiting the amount of flexure opening of the low stage discharge valve 200L is provided on the low stage discharge valve 200L. At the same time, it is fixed by a rivet 203. Further, a low-stage muffler discharge hole 210L for discharging the refrigerant in the low-stage muffler chamber 180L to the outside is provided in the outer peripheral wall portion of the low-stage end plate 160L. The low-stage muffler discharge hole 210L is provided in the radial direction at the same phase position in the circumferential direction of the low-stage and high-stage suction holes 135L and 135H of the compression unit 12 and the compressor housing 10.

  A high-stage muffler cover 170H is installed above the high-stage end plate 160H, and a high-stage muffler chamber 180H is formed between the high-stage end plate 160H. The high stage end plate 160H is provided with a high stage discharge hole 190H that connects the high stage compression chamber 133H and the high stage muffler chamber 180H of the high stage cylinder 121H, and the high stage discharge hole 190H contains the compressed refrigerant. A high-stage discharge valve 200H that prevents backflow is installed. Further, on the high-stage discharge valve 200H, a high-stage discharge valve presser 201H is fixed with a rivet together with the high-stage discharge valve 200H in order to limit the deflection opening amount of the high-stage discharge valve 200H. The high stage muffler chamber 180H reduces the pressure pulsation of the discharged refrigerant.

  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 the intermediate partition plate 140 are integrally fastened by bolts (not shown). . Out of the compression part 12 fastened together by bolts, the outer peripheral part of the high-stage end plate 160H is fixed to the compressor casing 10 by spot welding, and the compression part 12 is fixed to the compressor casing 10.

  As shown in FIG. 1, first, second, and third communication holes 101, 102, and 103 are substantially the same on the outer peripheral wall of the cylindrical compressor housing 10 in the axial direction and in order from the bottom. It is provided at a circumferential position. Further, an accumulator 25 made of an independent cylindrical sealed container is held by an accumulator holder 251 and an accumulator band 253 on the outer side of the compressor housing 10.

  A system connection pipe 255 connected to the low pressure side of the refrigeration cycle is connected to the center of the top of the accumulator 25, and one end of the bottom communication hole 257 provided at the bottom of the accumulator 25 extends to the upper part inside the accumulator 25. The low pressure communication pipe 31 whose other end is connected to the other end of the low stage suction pipe 104 is connected.

  The low-pressure communication pipe 31 that guides the low-pressure refrigerant of the refrigeration cycle to the low-stage compression unit 12L via the accumulator 25 is connected to the low-stage suction hole 135L of the low-stage cylinder 121L via the second communication hole 102 and the low-stage suction pipe 104. Has been.

  One end of the low-stage discharge pipe 105 is connected to the low-stage discharge hole 210L of the low-stage muffler chamber 180L through the first communication hole 101, and the high-stage suction hole 135H of the high-stage cylinder 121H is connected to the low-stage discharge hole 210L through the third communication hole 103. One end of the high stage suction pipe 106 is connected, and the other end of the low stage discharge pipe 105 and the other end of the high stage suction pipe 106 are connected by an intermediate communication pipe 23. The low-pressure connecting pipe 31 and the intermediate connecting pipe 23 are bent so as not to interfere with each other.

  The discharge part of the high stage compression unit 12H communicates with the compressor housing 10 via the high stage muffler chamber 180H. That is, the high-stage end plate 160H is provided with a high-stage discharge hole 190H that connects the high-stage compression chamber 133H and the high-stage muffler chamber 180H of the high-stage cylinder 121H, and the high-stage discharge hole 190H is compressed. A high-stage discharge valve 200H that prevents the reverse flow of the refrigerant is installed. The discharge part of the high stage muffler chamber 180 </ b> H communicates with the compressor housing 10. A discharge pipe 107 that is connected to the high pressure side of the refrigeration cycle and discharges high-pressure refrigerant to the refrigeration cycle side is connected to the top of the compressor housing 10.

  Lubricating oil is sealed in the compressor casing 10 up to the height of the high-stage cylinder 121H, and the lubricating oil circulates through the compression unit 12 by a blade pump (not shown) attached to the lower part of the rotary shaft 15, A portion that partitions the compression space of the compressed refrigerant is sealed by lubrication of the sliding parts and a minute gap.

  Next, the operation of the two-stage compression rotary compressor 1 described above will be described. When the two-stage compression rotary compressor 1 is operated, the refrigerant flowing into the accumulator 25 through the system connection pipe 255 from the low pressure side of the refrigeration cycle is liquid refrigerant at the lower part of the accumulator 25 and gas refrigerant at the upper part of the accumulator 25. Separated.

  When the low-stage piston 125L revolves in the low-stage cylinder 121L and the volume of the low-stage suction chamber 131L is expanded, the gas refrigerant in the accumulator 25 passes through the low-pressure communication pipe 31 and the low-stage suction pipe 104 to form a low stage. The air is sucked into the lower suction chamber 131L of the compression unit 12L. 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 switched to the low stage compression chamber 133L, and the refrigerant is compressed.

  When the pressure of the compressed refrigerant in the low-stage compression chamber 133L reaches the pressure of the low-stage muffler chamber 180L downstream of the low-stage discharge valve 200L provided in the low-stage discharge hole 190L, that is, the intermediate pressure, The stage discharge valve 200L is opened, the refrigerant is discharged into the low stage muffler chamber 180L, and after the pressure pulsation that causes noise in the low stage muffler chamber 180L is reduced, the high stage compression section passes through the intermediate connecting pipe 23. It is sent to the 12H high-stage suction chamber 131H.

  The refrigerant sent to the high stage suction chamber 131H of the high stage compression section 12H is compressed and discharged by the same action as the low stage compression section 12L, and after reducing pressure pulsation in the high stage muffler chamber 180H, And discharged into the compressor housing 10. Thereafter, the high-pressure refrigerant is sent to the upper portion of the motor 11 through a notch of the stator 111 (not shown) of the motor 11 and a gap between the core and the winding, and is discharged to the high-pressure side of the refrigeration cycle through the discharge pipe 107. The

The high-pressure refrigerant in the compressor housing 10 passes through the back pressure introduction passages 129L and 129H and is sent to the back of the low and high stage vane grooves 128L and 128H, and back pressure is applied to the low and high stage vanes 127L and 127H. However, since the thickness t _L of the low stage vane 127L is 75% to 90% of the thickness t _H of the high stage vane 127H, the tip of the low stage vane 127L is more than necessary at the low stage compression portion 12L. Is not pressed against the outer peripheral portion of the low-stage piston 125L.

  Further, in the present invention, the injection pipe is connected to the intermediate connecting pipe so that the refrigerant having the intermediate pressure between the high pressure (condensation pressure) and the low pressure (evaporation pressure) of the refrigeration cycle can be sucked into the high stage cylinder 121H as the injection refrigerant. You may apply to a two-stage rotary compressor.

  As described above, the two-stage compression rotary compressor according to the present invention is highly efficient and useful for long-term use.

It is a longitudinal cross-sectional view which shows the Example of the rotary compressor concerning this invention. It is a cross-sectional view of a low stage compression part. It is a cross-sectional view of a high stage compression part. It is a cross-sectional view which follows the AA line of FIGS. It is a cross-sectional view of a low stage end plate. It is sectional drawing which follows the BB line of FIG. It is a figure which shows the relationship between the compression chamber volume and compression chamber pressure of a two-stage compression rotary compressor. It is a figure which shows the pressure concerning the vane of a low stage side compression part and a high stage side compression part.

Explanation of symbols

1 Two-stage compression rotary compressor (rotary compressor)
DESCRIPTION OF SYMBOLS 10 Compressor housing | casing 11 Motor 12 Compression part 15 Rotating shaft 23 Intermediate connection pipe 25 Accumulator 31 Low pressure connection pipe 101 1st communication hole 102 2nd communication hole 103 3rd communication hole 104 Low stage suction pipe 105 Low stage discharge pipe 106 High Stage suction pipe 107 Discharge pipe 111 Stator 112 Rotor 12L Low stage compression part 12H High stage compression part 121L Low stage cylinder 121H High stage cylinder 123L Low stage cylinder inner wall 123H High stage cylinder inner wall 125L Low stage piston 125H High stage piston 127L Low stage vane 127H High stage vane 128L Low stage vane groove 128H High stage vane groove 129L, 129H Back pressure introduction path 130L Low stage working chamber 130H High stage working chamber 131L Low stage suction chamber 131H High stage suction chamber 133L Low stage compression chamber 133H High stage compression Chamber 135L Low stage suction hole 13 H High stage suction hole 140 Intermediate partition plate 151 Sub bearing support part 152L Low stage eccentric part 152H High stage eccentric part 153 Main bearing support part 160L Low stage end plate 160H High stage end plate 161L Sub bearing part 161H Main bearing part 170L Low-stage muffler cover 170H High-stage muffler cover 180L Low-stage muffler chamber 180H High-stage muffler chamber 190L Low-stage discharge hole 190H High-stage discharge hole 200L Low-stage discharge valve 200H High-stage discharge valve 201L Low-stage discharge valve press 201H High-stage discharge valve Presser 203 Rivet 210L Low stage muffler discharge hole 251 Accum holder 253 Accum band 255 System connection pipe 257 Bottom communication hole

Claims (5)

A cylindrical low-stage cylinder and an inner wall of the low-stage cylinder that revolves around the low-stage cylinder inner wall of the low-stage cylinder held by a low-stage eccentric part of a rotary shaft that is driven to rotate by a motor. A low-stage piston that forms a low-stage working chamber between the low-stage piston, and a low-stage vane groove of the low-stage cylinder that protrudes into the low-stage working chamber and abuts against the low-stage piston to make the low-stage working chamber low A low-stage compression section comprising a low-stage vane that is divided into a suction chamber and a low-stage compression chamber;
A high-stage cylinder inner wall of the high-stage cylinder that is stacked on the low-stage compression section via an intermediate partition plate and is held by a cylindrical high-stage cylinder and a high-stage eccentric part of a rotary shaft that is driven to rotate by the motor. And a high stage piston that revolves in the high stage cylinder to form a high stage working chamber with the inner wall of the high stage cylinder, and projects into the high stage working chamber from within the high stage vane groove of the high stage cylinder. A high-stage compression portion comprising a high-stage vane that abuts the high-stage piston and divides the high-stage working chamber into a high-stage suction chamber and a high-stage compression chamber;
A hermetically sealed compressor housing that houses the low-stage compression section and the high-stage compression section;
A low-pressure communication pipe that communicates a low-stage suction hole communicating with the low-stage suction chamber to a low-pressure side of the refrigeration cycle;
An intermediate connecting pipe for communicating the low stage discharge hole communicating with the low stage compression chamber and the high stage suction hole communicating with the high stage suction chamber;
A discharge pipe that communicates a high-stage discharge hole communicating with the high-stage compression chamber to a high-pressure side of the refrigeration cycle through the compressor housing;
A back pressure introduction path that communicates the inside of the compressor housing with the back of the low-stage vane groove and the high-stage vane groove;
A two-stage compression rotary compressor comprising:
A two-stage compression rotary compressor, wherein the low-stage vane and the low-stage vane groove are thinner than the high-stage vane and the high-stage vane groove.   2. The two-stage compression rotary compression according to claim 1, wherein the thickness of the low stage vane and the low stage vane groove is 75% to 90% of the thickness of the high stage vane and the high stage vane groove. Machine.   The two-stage compression rotary compressor according to claim 1 or 2, wherein the low-stage suction hole is made larger than the high-stage suction hole.   The two-stage compression rotary compressor according to any one of claims 1 to 3, wherein the low-stage discharge hole is made larger than the high-stage discharge hole.   5. The two-stage compression rotary compressor according to claim 1, wherein the eccentric amount of the low-stage eccentric portion and the eccentric amount of the high-stage eccentric portion are the same. .

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