JP2018080612A - Rotary Compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the generation of disproportionation reaction in refrigerant when liquid compression occurs.SOLUTION: In a rotary compressor, the refrigerant is HFO1123 refrigerant or mixed refrigerant including the HFO1123 refrigerant, and a vane has a predetermined clearance opened between the front end of the vane and the outer peripheral face of a piston when a second pressure in a compression chamber is higher than a first pressure in a pressure introduction path on one end side of a vane groove by a predetermined pressure or higher.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a rotary compressor.

  In a refrigeration cycle apparatus including a compressor that compresses refrigerant, R410A refrigerant is widely used as the refrigerant. Since the R410A refrigerant has a large global warming potential (GWP), a related technology using a refrigerant containing hydrofluoroolefin (HFO) 1123 (hereinafter referred to as HFO1123 refrigerant) as a refrigerant having a relatively small GWP. Are known.

International Publication No. 2014/057036

  The HFO1123 refrigerant described above has a property of causing a disproportionation reaction when energy is given under a certain condition. When a disproportionation reaction occurs in the refrigerant, a large amount of heat is generated. Therefore, when a disproportionation reaction occurs in the refrigeration cycle apparatus, the operation reliability of the refrigeration cycle apparatus including the compressor is reduced or a sudden pressure is applied. May cause the refrigerant piping to be damaged.

  Further, in the rotary compressor, the compression portion is immersed in oil (lubricating oil) for ensuring the sliding property of the piston in the cylinder for compressing the refrigerant and ensuring the airtightness of the compression chamber. In such a rotary compressor, when the engine is stopped for a long time at a low outside air temperature, a so-called refrigerant stagnation phenomenon occurs in which a large amount of refrigerant melts into oil. When the compressor is started in the refrigerant stagnation state, when the low-pressure side refrigerant in the refrigerant circulation path of the refrigeration cycle apparatus is supplied into the rotary compressor, there is a possibility that liquid compression occurs in which the liquid refrigerant is compressed. is there. In the rotary compressor using the refrigerant having the property of causing the disproportionation reaction as described above, when liquid compression occurs, the pressure of the refrigerant in the compression chamber may locally rise to, for example, about 30 Mpa, This high pressure may cause a disproportionation reaction in the refrigerant.

  The disclosed technology has been made in view of the above, and an object of the present invention is to provide a rotary compressor capable of suppressing the occurrence of a disproportionation reaction in a refrigerant when liquid compression occurs.

  One aspect of the rotary compressor disclosed in the present application is a vertically-placed cylindrical compressor housing that is provided with a refrigerant discharge portion at an upper portion and a refrigerant suction portion at a lower portion, and is sealed, A compression unit that compresses the refrigerant sucked from the suction unit and is discharged from the discharge unit; and a motor that is disposed in the upper part of the compressor housing and drives the compression unit. The section includes an annular cylinder, an upper end plate that closes the upper side of the cylinder, a lower end plate that closes the lower side of the cylinder, a rotating shaft that has an eccentric portion and is rotated by the motor, and the eccentricity And a piston that revolves along the inner peripheral surface of the cylinder and forms a cylinder chamber in the cylinder, and protrudes into the cylinder chamber from a vane groove provided in the cylinder, and a tip portion contacts the piston. Said Siri A vane that divides the chamber into a suction chamber and a compression chamber, a spring that is disposed on one end side of the vane groove and biases the vane toward the cylinder chamber, one end side of the vane groove, and the inside of the compressor housing. In the rotary compressor having a pressure introduction path that communicates with and a discharge hole that discharges the refrigerant compressed in the compression chamber from the compression chamber, the refrigerant is HFO1123 refrigerant, or a mixed refrigerant containing HFO1123 refrigerant, When the second pressure in the compression chamber is larger than a predetermined pressure than the first pressure in the pressure introduction path on one end side of the vane groove, the vane has the tip of the vane and the piston. A predetermined gap is opened between the outer peripheral surface and the outer peripheral surface.

  According to one aspect of the rotary compressor disclosed in the present application, it is possible to suppress a disproportionation reaction from occurring in the refrigerant when liquid compression occurs.

FIG. 1 is a longitudinal sectional view showing a rotary compressor of an embodiment. FIG. 2 is an exploded perspective view illustrating a compression unit of the rotary compressor according to the embodiment. FIG. 3 is a cross-sectional view of the compression portion of the rotary compressor of the embodiment as viewed from above. FIG. 4 illustrates a gap generated between the tip of the upper vane and the outer peripheral surface of the upper piston and a gap generated between the tip of the lower vane and the outer peripheral surface of the lower piston in the rotary compressor of the embodiment. FIG.

  Hereinafter, embodiments of a rotary compressor disclosed in the present application will be described in detail with reference to the drawings. In addition, the rotary compressor which this application discloses is not limited by the following examples.

  FIG. 1 is a longitudinal sectional view showing a rotary compressor of an embodiment. FIG. 2 is an exploded perspective view illustrating a compression unit of the rotary compressor according to the embodiment. FIG. 3 is a cross-sectional view of the compression portion of the rotary compressor of the embodiment as viewed from above.

  As shown in FIG. 1, the rotary compressor 1 includes a compression unit 12 disposed at a lower portion in a sealed vertical cylindrical compressor housing 10 and a rotation portion disposed at an upper portion in the compressor housing 10. A motor 11 that drives the compression unit 12 via a shaft 15 and a vertically installed cylindrical accumulator 25 that is fixed and sealed to the outer peripheral surface of the compressor housing 10 are provided.

  The accumulator 25 is connected to the upper cylinder chamber 130T (see FIG. 2) of the upper cylinder 121T via the upper suction pipe 105 and the accumulator upper curved pipe 31T as the suction part, and the lower suction pipe 104 and the lower accumulator curve as the suction part. A lower cylinder chamber 130S (see FIG. 2) is connected to the lower cylinder 121S through a pipe 31S. In the present embodiment, the positions of the upper suction pipe 105 and the lower suction pipe 104 overlap in the circumferential direction of the compressor housing 10 and are located at the same position.

  The motor 11 includes a stator 111 disposed on the outside and a rotor 112 disposed on the inside. The stator 111 is fixed to the inner peripheral surface of the compressor housing 10 in a shrink-fitted state. The rotor 112 is fixed to the rotating shaft 15 in a shrink-fitted state.

  The rotary shaft 15 is rotatably supported at the sub-shaft portion 151 below the lower eccentric portion 152S by the sub-bearing portion 161S provided on the lower end plate 160S, and the main shaft portion 153 above the upper eccentric portion 152T is at the upper end. The main bearing portion 161T provided on the plate 160T is rotatably supported. The rotating shaft 15 is provided with an upper eccentric portion 152T and a lower eccentric portion 152S with a phase difference of 180 degrees from each other. The upper piston 125T is supported by the upper eccentric portion 152T, and the lower eccentric portion 152S. The lower piston 125S is supported on the bottom. As a result, the rotary shaft 15 is rotatably supported with respect to the entire compression unit 12, and the upper piston 125T is caused to revolve along the inner peripheral surface of the upper cylinder 121T by rotation, and the lower piston 125S is moved to the lower cylinder 121S. Revolve along the inner circumference of the.

  Inside the compressor housing 10, the lubricity of sliding parts such as the upper piston 125T and the lower piston 125S sliding in the compression part 12 is ensured, and the upper compression chamber 133T (see FIG. 2) and the lower compression chamber 133S are secured. In order to seal (refer FIG. 2), the lubricating oil 18 is enclosed by the quantity which substantially immerses the compression part 12. FIG. An attachment leg 310 (see FIG. 1) that fixes a plurality of elastic support members (not shown) that support the entire rotary compressor 1 is fixed to the lower side of the compressor housing 10.

  As shown in FIG. 2, the compression unit 12 compresses the refrigerant sucked from the upper suction pipe 105 and the lower suction pipe 104, and discharges the refrigerant from a discharge pipe 107 serving as a discharge unit described later. As shown in FIG. 2, the compression portion 12 includes, from above, an upper end plate cover 170 </ b> T having a bulging portion in which a hollow space is formed, an upper end plate 160 </ b> T, an annular upper cylinder 121 </ b> T, an intermediate partition plate 140, The lower cylinder 121S, the lower end plate 160S, and a flat plate-like lower end plate cover 170S are laminated. The entire compression unit 12 is fixed by a plurality of through bolts 174 and 175 and auxiliary bolts 176 arranged substantially concentrically from above and below. As shown in FIGS. 2 and 3, the lower end plate 160S, the lower end plate cover 170S, the lower cylinder 121S, the intermediate partition plate 140, the upper cylinder 121T, the upper end plate 160T, and the upper end plate cover 170T have substantially the same phase position on a concentric circle. In addition, a plurality of bolt through holes 137 through which the through bolts 174 and 175 and the auxiliary bolt 176 are passed are provided.

  As shown in FIG. 3, an upper cylinder inner wall 123 </ b> T is formed in the upper cylinder 121 </ b> T along a concentric circle with the rotation shaft 15 of the motor 11. In the upper cylinder inner wall 123T, an upper piston 125T having an outer diameter smaller than the inner diameter of the upper cylinder 121T is disposed. As shown in FIG. 3, refrigerant is passed between the upper cylinder inner wall 123T and the upper piston 125T. An upper compression chamber 133T is formed for suction, compression and discharge. Similarly, a lower cylinder inner wall 123S is formed on the lower cylinder 121S along a concentric circle with the rotating shaft 15 of the motor 11. A lower piston 125S having an outer diameter smaller than the inner diameter of the lower cylinder 121S is disposed in the lower cylinder inner wall 123S. As shown in FIG. 3, refrigerant is passed between the lower cylinder inner wall 123S and the lower piston 125S. A lower compression chamber 133S is formed for suction, compression and discharge.

  As shown in FIG. 3, the upper cylinder 121 </ b> T has an upper protrusion 122 </ b> T that protrudes from the circular outer peripheral portion in the radial direction of the rotating shaft 15. The upper protruding portion 122T is provided with an upper vane groove 128T that extends radially outward from the upper cylinder chamber 130T. An upper vane 127T is slidably disposed in the upper vane groove 128T. The lower cylinder 121 </ b> S includes a lower side protrusion 122 </ b> S that protrudes from the circular outer peripheral portion in the radial direction of the rotation shaft 15. The lower side protrusion 122S is provided with a lower vane groove 128S extending radially outward from the lower cylinder chamber 130S. A lower vane 127S is slidably disposed in the lower vane groove 128S.

  The upper side protruding portion 122T and the lower side protruding portion 122S are formed over a predetermined protruding range along the circumferential direction of the rotating shaft 15. The upper side protruding part 122T and the lower side protruding part 122S are used as chuck holding parts for fixing to the processing jig when the upper cylinder 121T and the lower cylinder 121S are processed.

  The upper cylinder 121T is provided with an upper spring hole 124T communicating with the upper vane groove 128T from the outer surface of the upper protrusion 122T at a depth that does not penetrate the upper cylinder chamber 130T. An upper spring 126T that presses the back surface of the upper vane 127T is disposed in the upper spring hole 124T. The lower cylinder 121S is provided with a lower spring hole 124S communicating with the lower vane groove 128S from the outer surface of the lower side protruding portion 122S so as not to penetrate the lower cylinder chamber 130S. A lower spring 126S that presses the back surface of the lower vane 127S is disposed in the lower spring hole 124S.

  Further, the refrigerant compressed in the compressor housing 10 is introduced into the lower cylinder 121S through the radially outer side of the lower vane groove 128S and the compressor housing 10, and the pressure of the refrigerant is applied to the lower vane 127S. Thus, a lower pressure introduction path 129S for applying back pressure is formed. Further, the compressed refrigerant in the compressor housing 10 is introduced into the upper cylinder 121T by communicating the radially outer side of the upper vane groove 128T with the inside of the compressor housing 10 through the opening, and the compressed air in the compressor housing 10 is introduced into the upper vane 127T. An upper pressure introduction path 129T that applies back pressure by the pressure of the refrigerant is formed.

  As shown in FIG. 2, an upper suction hole 135 </ b> T that fits into the upper suction pipe 105 is provided in the upper protrusion 122 </ b> T of the upper cylinder 121 </ b> T. A lower suction hole 135S that fits into the lower suction pipe 104 is provided in the lower side protruding portion 122S of the lower cylinder 121S.

  As shown in FIG. 3, the upper cylinder chamber 130T is closed by an upper end plate 160T and an intermediate partition plate 140 on the upper and lower sides, respectively. The lower cylinder chamber 130S is closed at the top and bottom by an intermediate partition plate 140 and a lower end plate 160S, respectively.

  As shown in FIG. 3, the upper vane 127T is pressed by the urging force of the upper spring 126T and protrudes into the upper cylinder 121T from the upper vane groove 128T, and the tip 138T of the upper vane 127T is brought into contact with the outer peripheral surface 139T of the upper piston 125T. Abut. As a result, the upper cylinder chamber 130T is partitioned into an upper suction chamber 131T that communicates with the upper suction hole 135T and an upper compression chamber 133T that communicates with the upper discharge hole 190T provided in the upper end plate 160T. Similarly, the lower vane 127S is pressed by the urging force of the lower spring 126S and protrudes into the lower cylinder 121S from the lower vane groove 128S, and the tip portion 138S of the lower vane 127S comes into contact with the outer peripheral surface 139S of the lower piston 125S. Thus, the lower cylinder chamber 130S is partitioned into a lower suction chamber 131S communicating with the lower suction hole 135S and a lower compression chamber 133S communicating with the lower discharge hole 190S provided in the lower end plate 160S.

  The upper discharge hole 190T is provided in the vicinity of the upper vane groove 128T, and the lower discharge hole 190S is provided in the vicinity of the lower vane groove 128S. The refrigerant compressed in the upper compression chamber 133T and the lower compression chamber 133S is discharged from the upper compression chamber 133T and the lower compression chamber 133S through the upper discharge hole 190T and the lower discharge hole 190S.

  As shown in FIG. 2, the upper end plate 160T is provided with an upper discharge hole 190T that penetrates the upper end plate 160T and communicates with the upper compression chamber 133T of the upper cylinder 121T. An upper valve seat (not shown) is formed around the upper discharge hole 190T so as to protrude toward the upper discharge valve 200T, which will be described later, at the opening edge on the outlet side of the upper discharge hole 190T. The upper end plate 160T is formed with an upper discharge valve accommodating recess 164T extending in a groove shape from the position of the upper discharge hole 190T toward the outer periphery of the upper end plate 160T.

  The upper discharge valve accommodating recess 164T includes a reed valve type upper discharge valve 200T whose proximal end is fixed by an upper rivet 202T in the upper discharge valve accommodating recess 164T and whose distal end opens and closes the upper discharge hole 190T, and a proximal end Is overlaid on the upper discharge valve 200T and fixed in the upper discharge valve housing recess 164T by the upper rivet 202T, and the tip is curved (warped) in the direction in which the upper discharge valve 200T opens, thereby opening the upper discharge valve 200T. The entire upper discharge valve presser 201T to be regulated is accommodated.

  The lower end plate 160S is provided with a lower discharge hole 190S that penetrates the lower end plate 160S and communicates with the lower compression chamber 133S of the lower cylinder 121S. An annular lower valve seat surrounding the lower discharge hole 190S is formed on the opening edge of the lower discharge hole 190S on the outlet side so as to protrude toward the lower discharge valve 200S described later. The lower end plate 160S is formed with a lower discharge valve accommodating recess (not shown) extending in a groove shape from the position of the lower discharge hole 190S toward the outer periphery of the lower end plate 160S.

  The lower discharge valve housing recess accommodates a reed valve type lower discharge valve 200S that opens and closes the lower discharge hole 190S and the entire lower discharge valve presser 201S that regulates the opening degree of the lower discharge valve 200S. The lower discharge valve 200S is formed in a leaf spring shape from a metal material. The lower discharge valve 200S has a base end portion fixed to the lower discharge valve housing recess by a lower rivet 202S, and the distal end portion opens and closes the lower discharge hole 190S by elastic deformation. The lower discharge valve presser 201S has a base end overlapped with the lower discharge valve 200S and is fixed in the lower discharge valve housing recess by a lower rivet 202S, and a distal end is bent in a direction in which the lower discharge valve 200S opens ( The opening of the lower discharge valve 200S is regulated by the tip of the warped contact with the lower discharge valve 200S.

  An upper end plate cover chamber 180T is formed between the upper end plate 160T and the upper end plate cover 170T having a bulging portion that are closely fixed to each other. A lower end plate cover chamber 180S (see FIG. 1) is formed between the lower end plate 160S and the flat plate-like lower end plate cover 170S which are closely fixed to each other. A refrigerant passage hole 136 that penetrates the lower end plate 160S, the lower cylinder 121S, the intermediate partition plate 140, the upper cylinder 121T, and the upper end plate 160T and communicates the lower end plate cover chamber 180S and the upper end plate cover chamber 180T is provided.

  Below, the flow of the refrigerant | coolant by rotation of the rotating shaft 15 is demonstrated. In the upper cylinder chamber 130T, the upper piston 125T fitted to the upper eccentric portion 152T of the rotary shaft 15 is rotated on the outer peripheral surface of the upper cylinder chamber 130T (the inner peripheral surface of the upper cylinder 121T) by the rotation of the rotary shaft 15. The upper suction chamber 131T sucks refrigerant from the upper suction pipe 105 while expanding the volume, and the upper compression chamber 133T compresses the refrigerant while reducing the volume, and the pressure of the compressed refrigerant is discharged upward. When the pressure is higher than the pressure in the upper end plate cover chamber 180T outside the valve 200T, the upper discharge valve 200T is opened and the refrigerant is discharged from the upper compression chamber 133T to the upper end plate cover chamber 180T. The refrigerant discharged into the upper end plate cover chamber 180T is discharged into the compressor housing 10 from an upper end plate cover discharge hole 172T (see FIG. 1) provided in the upper end plate cover 170T.

  Further, in the lower cylinder chamber 130S, the lower piston 125S fitted to the lower eccentric portion 152S of the rotary shaft 15 by the rotation of the rotary shaft 15 causes the outer peripheral surface of the lower cylinder chamber 130S (the inner peripheral surface of the lower cylinder 121S). ), The lower suction chamber 131S sucks in the refrigerant from the lower suction pipe 104 while increasing the volume, and the lower compression chamber 133S compresses the refrigerant while reducing the volume, and the pressure of the compressed refrigerant is reduced. When the pressure in the lower end plate cover chamber 180S outside the lower discharge valve 200S becomes higher, the lower discharge valve 200S opens and the refrigerant is discharged from the lower compression chamber 133S to the lower end plate cover chamber 180S. The refrigerant discharged into the lower end plate cover chamber 180S passes through the refrigerant passage hole 136 and the upper end plate cover chamber 180T and is discharged into the compressor housing 10 from the upper end plate cover discharge hole 172T provided in the upper end plate cover 170T. .

  The refrigerant discharged into the compressor housing 10 is notched (not shown) provided on the outer periphery of the stator 111 and communicated with the upper and lower sides, or a gap (not shown) between winding portions of the stator 111, or the stator 111. Is guided to the upper side of the motor 11 through a gap 115 (see FIG. 1) between the rotor 112 and the rotor 112, and is discharged from a discharge pipe 107 serving as a discharge portion disposed on the upper portion of the compressor housing 10.

(Characteristic configuration of rotary compressor)
Next, a characteristic configuration of the rotary compressor 1 of the embodiment will be described. FIG. 4 shows a gap generated between the tip portion 138T of the upper vane 127T and the outer peripheral surface 139T of the upper piston 125T, the tip portion 138S of the lower vane 127S and the outer peripheral surface 139S of the lower piston 125S in the rotary compressor 1 of the embodiment. It is a cross-sectional view for demonstrating the gap | interval which arises between these.

  In the rotary compressor 1 of the present embodiment, as the refrigerant, an HFO1123 refrigerant having a property of causing a disproportionation reaction when energy is given under a condition of a constant temperature or pressure, or a mixed refrigerant containing an HFO1123 refrigerant is used. It has been. Therefore, in the rotary compressor 1 of the present embodiment, liquid compression of the refrigerant occurs in the upper compression chamber 133T (hereinafter, the same applies to the lower compression chamber 133S, and the description of the lower compression chamber 133S is omitted). In order to avoid a high pressure in the upper compression chamber 133T, the refrigerant is actively released from the upper compression chamber 133T when the pressure in the upper compression chamber 133T reaches a predetermined pressure. It is characterized in that it suppresses the occurrence of a disproportionation reaction in the refrigerant when compression occurs.

  When the rotary compressor is driven at a low pressure ratio, the pressure that presses the upper vane (lower vane) to the upper piston (lower piston) decreases, and when driven at a high speed, it acts on the upper vane (lower vane). Since the centrifugal force to be increased becomes large, there is a possibility that the tip of the upper vane (lower vane) and the outer peripheral surface of the upper piston (lower piston) located at the top dead center are separated. The displacement of the upper spring when the upper vane retracts relative to the upper piston, and the displacement of the lower spring when the lower vane retracts relative to the lower piston may increase, leading to damage to the upper spring and lower spring. Becomes higher. For this reason, in general, in a rotary compressor, it is preferable to make the gap between the tip of the upper vane (lower vane) and the outer peripheral surface of the upper piston (lower piston) as small as possible.

  On the other hand, the rotary compressor 1 of the present embodiment is premised on the use of a refrigerant that may cause a disproportionation reaction due to liquid compression. The tip 138T of the upper vane 127T and the upper piston 125T are used. The outer peripheral surface 139T of the lower vane 127S and the outer surface 139S of the lower piston 125S are intentionally opened.

  Specifically, as shown in FIG. 4, the upper vane 127T has a second pressure P2 in the upper compression chamber 133T that is higher than the first pressure P1 in the upper pressure introduction path 129T on one end side of the upper vane groove 128T. When the pressure is larger than a predetermined pressure, the upper vane groove is formed so that a predetermined gap D for allowing the refrigerant to pass is opened between the tip 138T (sliding surface) of the upper vane 127T and the outer peripheral surface 139T of the upper piston 125T. 128T. Similarly, when the second pressure P2 in the lower compression chamber 133S is greater than a predetermined pressure, the lower vane 127S is larger than the first pressure P1 in the lower pressure introduction path 129S on one end side of the lower vane groove 128S. A lower vane groove 128S is provided between the tip 138S of the lower vane 127S and the outer peripheral surface 139S of the lower piston 125S so as to open a predetermined gap D for allowing the refrigerant to pass therethrough. In each of the upper cylinder 121T and the lower cylinder 121S, the first pressure P1 and the second pressure P2 are equal.

  That is, when the second pressure P2 in the upper compression chamber 133T becomes equal to or higher than a predetermined pressure, the refrigerant (liquid refrigerant and gas refrigerant) in the upper compression chamber 133T is passed through the gap D between the upper vane 127T and the upper piston 125T. For example, in order to sufficiently escape to the upper suction chamber 131T and to sufficiently escape into the compressor housing 10 through the upper vane groove 128T and the upper pressure introducing portion 129T, the upper vane 127T is retreated into the upper vane groove 128T. A vane 127T is provided in the upper vane groove 128T. Similarly, when the second pressure P2 in the lower compression chamber 133S becomes equal to or higher than a predetermined pressure, the refrigerant (liquid refrigerant and gas refrigerant) in the lower compression chamber 133S passes through the gap D between the lower vane 127S and the lower piston 125S. For example, the lower vane 127S is retreated into the lower vane groove 128S in order to sufficiently escape to the lower suction chamber 131S and to sufficiently escape into the compressor housing 10 through the lower vane groove 128S and the lower pressure introducing portion 129S. A lower vane 127S is provided in the lower vane groove 128S. Thus, when the pressure in the upper compression chamber 133T becomes equal to or higher than a predetermined pressure, the upper vane 127T retracts into the upper vane groove 128T, and the gap between the tip 138T of the upper vane 127T and the outer peripheral surface 139T of the upper piston 125T. The biasing force and mechanical strength of the upper spring 126T, the length of the upper vane 127T and the length of the upper vane groove 128T with respect to the advancing and retreating direction of the upper vane 127T are set so that a gap D of a predetermined dimension d is opened. (The same applies to the lower vane 127S).

  The thickness of the upper vane 127T with respect to the circumferential direction of the upper cylinder 121T and the thickness of the lower vane 127S with respect to the circumferential direction of the lower cylinder 121S are set to, for example, 3.2 mm or more. The movable range of the upper vane 127T in the upper vane groove 128T associated with the revolution of the upper piston 125T with respect to the advance / retreat direction and the movable range of the lower vane 127S within the lower vane groove 128S associated with the revolution of the lower piston 125S include, for example, It is set to about 11 mm. This movable range includes a dimensional tolerance (for example, about 0.5 mm) of the lengths of the upper vane 127T and the lower vane 127S.

  In the rotary compressor 1 of the embodiment, the first pressure P1 is about 3 Mpa and the second pressure P2 is about 5 MPa. When the second pressure P2 becomes 1.5 times or more of the first pressure P1, the tip portion 138T of the upper piston 127T and the outer peripheral surface 139T of the upper piston 125T and the tip portion of the lower piston 127S are A gap D having a predetermined dimension d is opened between 138S and the outer peripheral surface 139S of the upper and lower pistons 125S. Further, the upper vane 127T and the lower vane 127S are configured to open the gap D having a predetermined dimension d when the second pressure P2 becomes 5 MPa or more, for example. Since the upper pressure introduction path 129T and the lower pressure introduction path 129S communicate with the compressor housing 10, the first pressure P1 in the upper pressure introduction path 129T and the lower pressure introduction path 129S is the compressor housing. Equal to the pressure in the body 10.

  The gap D having the predetermined dimension d is 0.5 mm or more and 1.0 mm in the forward / backward direction of the upper vane 127T (the radial direction of the upper cylinder 121T) with the upper piston 125T positioned at the top dead center. The following are set (the same applies to the lower vane 127S). When the dimension d of the gap D exceeds 1.0 mm, the amount of displacement of the upper spring 126T when the upper vane 127T is retracted with respect to the upper piston 125T, and when the lower vane 127S is retracted with respect to the lower piston 125S The amount of displacement of the lower spring 126S becomes large, and there is a high possibility that the upper spring 126T and the lower spring 126S will be damaged. On the other hand, when the dimension d of the gap D is less than 0.5 mm, it is difficult to properly release the high-pressure refrigerant from the upper compression chamber 133T and the lower compression chamber 133S.

  Even when the upper piston 125T is located at the top dead center, when the second pressure P2 in the upper compression chamber 133T reaches a predetermined pressure or more due to the occurrence of liquid compression in the upper compression chamber 133T. Further, the upper vane 127T is retracted from the upper piston 125T, and the gap D having a predetermined dimension d is opened. The refrigerant in the upper compression chamber 133T is discharged from the gap D into the compression housing 10 through the upper suction chamber 131T, the upper vane groove 128T, and the like. For this reason, the second pressure P2 in the upper compression chamber 133T is appropriately reduced. Accordingly, it is possible to suppress the disproportionation reaction in the refrigerant when liquid compression occurs in the upper compression chamber 133T (the same applies to the lower compression chamber 133S).

  As described above, the rotary compressor 1 of the embodiment uses the HFO 1123 refrigerant or the mixed refrigerant containing the HFO 1123 refrigerant as the refrigerant, and the first pressure P1 in the upper pressure introduction path 129T on one end side of the upper vane groove 128T. When the second pressure P2 in the upper compression chamber 133T is greater than or equal to a predetermined pressure, a gap D having a predetermined dimension d is formed between the tip 138T of the upper vane 127T and the outer peripheral surface 139T of the upper piston 125T. open. Thereby, when liquid compression occurs in the upper compression chamber 133T, the refrigerant can be released from the upper compression chamber 133T through the gap D between the upper vane 127T and the upper piston 125T. For this reason, since it can suppress that the inside of the upper compression chamber 133T becomes high pressure by liquid compression, it can suppress that disproportionation reaction arises in a refrigerant | coolant (same also about lower vane 127S).

  Further, the upper vane 127T in the rotary compressor 1 of the embodiment opens the gap D having a predetermined dimension d when the second pressure P2 becomes 1.5 times or more the first pressure P1. As a result, when liquid compression occurs in the upper compression chamber 133T, it is possible to properly release the refrigerant from the upper compression chamber 133T, and the pressure in the upper compression chamber 133T is effectively reduced to disproportionate the refrigerant. It is possible to prevent the reaction from occurring (the same applies to the lower vane 127S).

  Further, the upper vane 127T in the rotary compressor 1 of the embodiment opens the gap D having a predetermined dimension d when the second pressure P2 becomes 5 MPa or more. As a result, when liquid compression occurs in the upper compression chamber 133T, it is possible to properly release the refrigerant from the upper compression chamber 133T, and the pressure in the upper compression chamber 133T is effectively reduced to disproportionate the refrigerant. It is possible to prevent the reaction from occurring (the same applies to the lower vane 127S).

  Further, in the rotary compressor 1 of the embodiment, the gap D having the predetermined dimension d is 0.5 mm or more and 1.0 mm or less in the advance / retreat direction of the upper vane 127T. Thereby, it is possible to prevent the upper spring 126T from being damaged, and to properly release the high-pressure refrigerant from the upper compression chamber 133T (the same applies to the lower vane 127S).

  The above-described embodiment is applied to the two-cylinder rotary compressor 1, but may be applied to a one-cylinder rotary compressor, and the one-cylinder type has the same effect as the two-cylinder type. Can be obtained.

DESCRIPTION OF SYMBOLS 1 Rotary compressor 10 Compressor housing 11 Motor 12 Compression part 15 Rotating shaft 25 Accumulator 105 Upper suction pipe (suction part)
104 Lower suction pipe (suction part)
107 Discharge pipe (discharge section)
111 Stator 112 Rotor 121T Upper cylinder 121S Lower cylinder 124T Upper spring hole 124S Lower spring hole 125T Upper piston 125S Lower piston 126T Upper spring 126S Lower spring 127T Upper vane 127S Lower vane 128T Upper vane groove 128S Lower vane groove 129T Upper pressure introduction path 129S Lower pressure introduction path 130T Upper cylinder chamber 130S Lower cylinder chamber 131T Upper suction chamber 131S Lower suction chamber 133T Upper compression chamber 133S Lower compression chamber 138T, 138S Tip portion 139T, 139S Outer peripheral surface 152T Upper eccentric portion 152S Lower eccentric portion 160T Upper end Plate 160S Lower end plate 190T Upper discharge hole 190S Lower discharge hole d Size D Gap P1 First pressure P2 Second pressure

Claims (4)

A vertically-placed cylindrical compressor casing that is provided with a refrigerant discharge section at the top and a refrigerant suction section at the bottom and sealed, and a refrigerant that is disposed at the bottom of the compressor casing and is sucked from the suction section A compression unit that compresses and discharges from the discharge unit, and a motor that is disposed at an upper part in the compressor housing and drives the compression unit,
The compression portion includes an annular cylinder, an upper end plate that closes the upper side of the cylinder, a lower end plate that closes the lower side of the cylinder, a rotating shaft that has an eccentric portion and is rotated by the motor, A piston that fits in the eccentric part and revolves along the inner peripheral surface of the cylinder to form a cylinder chamber in the cylinder, and projects from the vane groove provided in the cylinder into the cylinder chamber, and has a tip portion on the piston. A vane that divides the cylinder chamber into a suction chamber and a compression chamber by abutment, a spring that is disposed on one end side of the vane groove and biases the vane toward the cylinder chamber, one end side of the vane groove, and the compression A pressure introduction path communicating with the inside of the machine casing, a discharge hole for discharging the refrigerant compressed in the compression chamber from the compression chamber,
In a rotary compressor having
The refrigerant is HFO1123 refrigerant or a mixed refrigerant containing HFO1123 refrigerant,
When the second pressure in the compression chamber is larger than a predetermined pressure than the first pressure in the pressure introduction path on one end side of the vane groove, the vane has the tip of the vane and the piston. A rotary compressor characterized in that a predetermined gap is opened between the outer peripheral surface and the outer peripheral surface. The vane opens the predetermined gap when the second pressure becomes 1.5 times or more of the first pressure.
The rotary compressor according to claim 1. The vane opens the predetermined gap when the second pressure becomes 5 MPa or more.
The rotary compressor according to claim 1 or 2. The predetermined gap is 0.5 mm or more and 1.0 mm or less in the advancing and retracting direction of the vane.
The rotary compressor according to any one of claims 1 to 3.

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