JP2017031887A - Scroll compressor and heat cycle system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll compressor and a heat cycle system, which have a multistate compression mechanism and can achieve downsizing of the device with a simple configuration even if a refrigerant circulation amount introduced in the low-stage compression mechanism is different from a refrigerant circulation amount introduced in the high-stage compression mechanism.SOLUTION: A scroll compressor has a division wall for dividing a compression chamber into an outer compression part and an inner compression part between a winding start on the center side and a winding end on the outer side of a fixed scroll plate-shaped spiral tooth 11b. An orbital scroll plate-shaped spiral tooth 12b is formed with a division region at a position corresponding to the division wall so as not to interfere with the division wall in association with an orbital motion. A height h2 of a fixed scroll plate-shaped spiral tooth 31 and an orbital scroll plate-shaped spiral tooth 33, which form the inner compression part, is set higher than a height h1 of a fixed scroll plate-shaped spiral tooth 30 and an orbital scroll plate-shaped spiral tooth 32, which form the outer compression part.SELECTED DRAWING: Figure 5

Description

  The present invention has a multi-stage compression mechanism, and the apparatus has a simple configuration even when the refrigerant circulation amount introduced into the low-stage compression mechanism and the refrigerant circulation amount introduced into the high-stage compression mechanism are different. The present invention relates to a scroll compressor and a thermal cycle system that can realize downsizing.

  Conventionally, there is one in which a two-stage compression mechanism is provided in one scroll compressor. For example, Patent Document 1 includes a land portion that divides the compression chamber of the fixed scroll into two stages, and a low-stage compression mechanism on the outer peripheral side and a high-stage compression mechanism on the inner peripheral side divided by the land part. A two-stage compression scroll compressor is described in which air compressed by a low-stage compression mechanism is introduced into a high-stage compression mechanism.

JP 2004-332556 A

  By the way, the above-described two-stage compression scroll compressor compresses the refrigerant circulation amount compressed by the low-stage compression mechanism as it is by the high-stage compression mechanism. Here, when a two-stage compression scroll compressor is to be applied to a two-stage compression two-stage expansion cycle compressor, an intermediate-pressure refrigerant expanded by a high-stage expansion valve is introduced into the high-stage compression mechanism. Therefore, the refrigerant circulation amount introduced into the high-stage compression mechanism is larger than the refrigerant circulation amount introduced into the low stage, and it has been difficult to realize the two-stage compression. In order to realize this two-stage compression / two-stage expansion cycle, a pair of scroll compressors including a low-stage scroll compressor and a high-stage scroll compressor is required. For this reason, the scroll compressor of the two-stage compression / two-stage expansion cycle has an increased apparatus configuration and a complicated piping configuration.

  The present invention has been made in view of the above, and has a multi-stage compression mechanism, and the refrigerant circulation amount introduced into the low-stage compression mechanism is different from the refrigerant circulation amount introduced into the high-stage compression mechanism. Even if it is a case, it aims at providing the scroll compressor and thermal cycle system which can implement | achieve size reduction of an apparatus with a simple structure.

  In order to solve the above-described problems and achieve the object, a scroll compressor according to the present invention forms a compression chamber by meshing fixed scroll plate-like spiral teeth and orbiting scroll plate-like spiral teeth, and said orbiting scroll A scroll compressor that compresses the refrigerant in the compression chamber by revolving the plate-like spiral teeth, wherein the compression chamber is disposed between a center start and an outer end of the fixed scroll plate spiral teeth. Is divided into an outer compression portion and an inner compression portion, and the orbiting scroll plate-like spiral teeth are divided into positions corresponding to the division walls so as not to interfere with the division wall with the revolution movement. The fixed scroll plate-like spiral teeth that form a region and form the inner compression portion and the height of the orbiting scroll plate-like spiral teeth are the fixed scroll plate that forms the outer compression portion Higher than the height of the spiral tooth and the orbiting scroll plate-like spiral tooth and it said.

  In the scroll compressor according to the present invention, in the above invention, the outer compression portion compresses and discharges an outer suction port that sucks in the low-pressure refrigerant and a refrigerant sucked from the outer suction port to an intermediate pressure. An outer discharge port, and the inner compression portion has an inner suction port for sucking in the refrigerant discharged from the outer discharge port and a refrigerant introduced from the outside, and the refrigerant sucked in from the inner suction port up to a high pressure. It has an inside discharge port which discharges by compressing.

  In the scroll compressor according to the present invention, in the above invention, the outer winding end position of the fixed scroll plate-like spiral teeth is an extension angle θa from the winding end position of the fixed scroll plate-like spiral teeth in the symmetrical scroll. Is stretched at 0 ° <θa ≦ 180 °.

  In the scroll compressor according to the present invention, in the above invention, the fixed scroll plate-like spiral teeth and the orbiting scroll plate-like spiral teeth are each erected on a base plate, and one of the base plates has the other An outer wall that slides with the base plate is formed, and a ring-shaped seal is provided on the sliding surface between the tip of the outer wall and the other base plate.

  Moreover, the scroll compressor according to the present invention is characterized in that, in the above invention, the ring-shaped seal has a thermal expansion absorbing portion that absorbs thermal expansion.

  The scroll compressor according to the present invention is characterized in that, in the above invention, the thermal expansion absorbing portion is one or more divided gaps inclined with respect to an axial direction of the revolution motion.

  The scroll compressor according to the present invention is characterized in that, in the above invention, the thermal expansion absorbing portion is one or more divided gaps inclined with respect to a circumferential direction of the ring-shaped seal.

  The scroll compressor according to the present invention is characterized in that, in the above invention, the scroll compressor is one or more space portions formed in a region sandwiched between an outer peripheral surface and an inner peripheral surface of the ring-shaped seal.

  The thermal cycle system according to the present invention includes a scroll compressor described above, a condenser that condenses the high-pressure refrigerant compressed by the scroll compressor, and a refrigerant condensed by the condenser under reduced pressure. The intermediate-stage high-pressure expansion valve and the intermediate-pressure refrigerant introduced from the high-stage expansion valve are separated into gas and liquid, and the gas is introduced into the inner compression section as the intermediate-pressure refrigerant of the scroll compressor. A gas-liquid separator; a low-stage expansion valve that decompresses and expands the liquid in the gas-liquid separator as an intermediate-pressure refrigerant; and a low-pressure refrigerant introduced from the low-stage expansion valve is evaporated, And an evaporator that is introduced into the outer compression portion as the refrigerant.

  The thermal cycle system according to the present invention is characterized in that, in the above invention, a supercooler is provided between the condenser and the high stage expansion valve.

  The heat cycle system according to the present invention is characterized in that, in the above invention, a heat exchanger is provided for performing heat exchange between the refrigerant derived from the gas-liquid separator and the refrigerant derived from the evaporator. And

  The heat cycle system according to the present invention is the above invention, further comprising a heat exchanger that performs heat exchange between the refrigerant just before being introduced into the high stage expansion valve and the refrigerant derived from the evaporator. It is characterized by that.

  Moreover, the thermal cycle system according to the present invention includes the scroll compressor described above, a condenser that condenses the high-pressure refrigerant compressed by the scroll compressor, and a branch point that condenses the refrigerant condensed by the condenser. An intermediate expansion valve that branches at one of the branches and decompresses and expands one of the refrigerants to an intermediate pressure; an intermediate-pressure refrigerant introduced from the intermediate expansion valve; and another high-pressure refrigerant branched at the branch point A heat exchanger for introducing the heat-exchanged intermediate pressure refrigerant into the inner compression section as an intermediate-pressure refrigerant of the scroll compressor, and a high-pressure refrigerant heat-exchanged by the heat exchanger. An expansion valve that generates a low-pressure refrigerant by decompression and expansion, and an evaporator that evaporates the low-pressure refrigerant introduced from the expansion valve and introduces the low-pressure refrigerant into the outer compression unit as the low-pressure refrigerant of the scroll compressor. That And butterflies.

  The thermal cycle system according to the present invention is characterized in that, in the above invention, a supercooler is provided between the condenser and the branch point.

  According to the present invention, the orbiting scroll plate is provided with a dividing wall that divides the compression chamber into an outer compression portion and an inner compression portion between the center winding start and the outer winding end of the fixed scroll plate spiral tooth. The fixed scroll plate-like spiral teeth and the swivel teeth that form a divided region at a position corresponding to the dividing wall and form the inner compression portion so that the helical spiral teeth do not interfere with the dividing wall along with a revolving motion The height of the scroll plate-like spiral teeth is higher than the height of the fixed scroll plate-like spiral teeth and the orbiting scroll plate-like spiral teeth that form the outer compression portion. Thereby, even when the refrigerant circulation amount introduced into the low-stage compression mechanism is different from the refrigerant circulation amount introduced into the high-stage compression mechanism, the apparatus can be reduced in size with a simple configuration. it can.

FIG. 1 is a circuit diagram showing a schematic configuration of a thermal cycle system to which a scroll compressor according to a first embodiment of the present invention is applied. FIG. 2 is a PH diagram of the thermal cycle system shown in FIG. FIG. 3 is a cross-sectional view showing the structure of the scroll compressor. 4 is a cross-sectional view taken along line AA shown in FIG. FIG. 5 is a cross-sectional view of the fixed scroll and the orbiting scroll shown in FIG. 6 is a perspective view of the fixed scroll shown in FIG. 4 as viewed obliquely from below. FIG. 7 is a perspective view of the orbiting scroll shown in FIG. 4 as viewed obliquely from above. FIG. 8 is an explanatory diagram for explaining the compression operation of the symmetric scroll compressor. FIG. 9 is an explanatory diagram for explaining the compression operation of the asymmetric scroll compressor. FIG. 10 is an explanatory diagram showing the relationship between the position on the involute curve and the extension angle. FIG. 11 is a diagram comparing the compression operations of the symmetric scroll compressor and the asymmetric scroll compressor. FIG. 12 is an explanatory diagram for explaining reduction of recompression loss by the compression operation of the asymmetric scroll compressor. FIG. 13 is a cross-sectional view showing a state where the orbiting scroll is tilted. FIG. 14 is an explanatory diagram for explaining a decrease in compression efficiency of the outer compression unit in the state of FIG. FIG. 15 is an explanatory diagram for explaining a decrease in volume efficiency of the inner compression portion in the state of FIG. 13. FIG. 16 is a cross-sectional view showing a state in which the ring-shaped seal is provided on the front end surface of the outer wall of the fixed scroll. FIG. 17 is a cross-sectional view taken along line BB in the case where the scroll compressor shown in FIG. 3 is provided with a ring-shaped seal. FIG. 18 is a cross-sectional view showing a state in which the ring-shaped seal is provided on the base plate of the orbiting scroll. FIG. 19 is a diagram showing an example in which a split gap is provided in the ring-shaped seal. FIG. 20 is a diagram showing an example in which a split gap is provided in the ring-shaped seal. FIG. 21 is a diagram illustrating an example in which a space portion is provided in the ring-shaped seal. FIG. 22 is a circuit diagram illustrating an example of a thermal cycle system. 23 is a PH diagram of the thermal cycle system shown in FIG. FIG. 24 is a circuit diagram illustrating an example of a thermal cycle system. 25 is a PH diagram of the heat cycle system shown in FIG. FIG. 26 is a circuit diagram illustrating an example of a thermal cycle system. 27 is a PH diagram of the thermal cycle system shown in FIG. FIG. 28 is a circuit diagram illustrating an example of a thermal cycle system. 29 is a PH diagram of the heat cycle system shown in FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings.

[Embodiment 1]
(Overview of applicable systems)
FIG. 1 is a circuit diagram showing a schematic configuration of a thermal cycle system 1 to which a scroll compressor 2 according to Embodiment 1 of the present invention is applied. FIG. 2 is a PH diagram of the thermal cycle system 1 shown in FIG. The scroll compressor 2 is a two-stage compressor. Furthermore, the thermal cycle of the thermal cycle system 1 is a two-stage compression two-stage expansion cycle.

  The high-stage side compression chamber of the scroll compressor 2 generates a high-pressure refrigerant RH having a refrigerant circulation amount GH and introduces it into the condenser 3 (from point P2 to point P3 in FIG. 2). The high-pressure refrigerant RH is radiated and condensed by the condenser 3 and further subcooled by the supercooler 4 (from point P3 to point P4 in FIG. 2). Thereafter, the high-pressure refrigerant RH is decompressed and expanded by the high stage expansion valve 5 (from the point P4 to the point P5 in FIG. 2) and becomes an intermediate-pressure refrigerant RM and introduced into the gas-liquid separator 6. The intermediate-pressure refrigerant RM1 in the gaseous state that is the vapor of the intermediate-pressure refrigerant RM is introduced into the high-stage compression chamber of the scroll compressor 2 (point P2 in FIG. 2). On the other hand, the intermediate-pressure refrigerant RM2 in the liquid state among the intermediate-pressure refrigerant RM is decompressed and expanded by the low-stage expansion valve 7 (from point P6 to point P7 in FIG. 2) and becomes the low-pressure refrigerant RL and is introduced into the evaporator 8. The The evaporator 8 evaporates the low-pressure refrigerant RL (from the point P7 to the point P1 in FIG. 2) and introduces it into the low-stage compression chamber of the scroll compressor 2 (the point P1 in FIG. 2).

  Thereafter, the lower stage compression chamber of the scroll compressor 2 compresses the introduced low-pressure refrigerant RL to the intermediate-pressure refrigerant RM3. The high pressure side compression chamber of the scroll compressor 2 compresses the intermediate pressure refrigerants RM1, RM3 to the high pressure refrigerant RH. Therefore, the refrigerant circulation amount GL in the liquid state separated by the gas-liquid separator 6 is introduced into the lower stage compression chamber of the scroll compressor 2. On the other hand, the refrigerant circulation amount GM in the gas state separated by the gas-liquid separator 6 and the refrigerant circulation amount GL introduced from the low-stage compression chamber are added to the high-stage compression chamber of the scroll compressor 2. Refrigerant circulation amount GH is introduced. That is, the refrigerant circulation amount introduced into the higher stage compression chamber is larger than the refrigerant circulation amount introduced into the lower stage compression chamber.

(Scroll compressor)
FIG. 3 is a cross-sectional view showing the structure of the scroll compressor 2. 4 is a cross-sectional view taken along the line AA shown in FIG. 5 is a cross-sectional view of the fixed scroll 11 and the orbiting scroll 12 shown in FIG. FIG. 6 is a perspective view of the fixed scroll 11 shown in FIG. 4 as viewed obliquely from below. FIG. 7 is a perspective view of the orbiting scroll 12 shown in FIG.

  The fixed scroll 11 and the orbiting scroll 12 form a two-stage compression by forming a later-described outer compression portion 40 that functions as a low-pressure side compression chamber and a later-described inner compression portion 41 that functions as a high-pressure side compression chamber. As shown in FIG. 3, the fixed scroll 11 and the orbiting scroll 12 are provided in the housing 10 formed by the housings 10a and 10b. Two-stage compression is performed by the revolving motion of the orbiting scroll 12 with respect to the fixed scroll 11 in the rotational direction AL. The crankshaft 13 transmits a rotational force from a rotational drive source (not shown) to the orbiting scroll 12. The thrust bearing 14 is pivotally supported in the thrust direction with respect to the rotation of the orbiting scroll 12. An intermediate pressure chamber 16 and a high pressure chamber 17 are formed in the housing 10. The crankshaft 13 is provided with a balance weight 15 for balancing the rotation of the orbiting scroll 12 with respect to the revolving motion.

  The low-pressure refrigerant suction pipe L <b> 1 is a pipe that introduces the low-pressure refrigerant RL into the outer compression unit 40. The intermediate pressure refrigerant suction pipe L <b> 2 is a pipe that introduces the intermediate pressure refrigerant RM <b> 1 into the intermediate pressure chamber 16. The high-pressure refrigerant discharge pipe L3 is a pipe that discharges the high-pressure refrigerant RH discharged from the inner compression portion 41 through the discharge valve 18 and the high-pressure chamber 17 to the outside of the housing 10.

(2-stage compression mechanism)
As shown in FIGS. 4-7, the fixed scroll 11 has the fixed scroll plate-shaped spiral tooth 11b erected on the base plate 11a. The orbiting scroll 12 has an orbiting scroll plate-like spiral tooth 12b erected on the base plate 12a. The fixed scroll 11 and the orbiting scroll 12 form the outer compression part 40 and the inner compression part 41 by meshing the tip of the fixed scroll plate-like spiral tooth 11b and the tip of the orbiting scroll plate-like spiral tooth 12b. Then, in the outer compression part 40 and the inner compression part 41, compression chambers are formed on the outer side and the inner side of the orbiting scroll 12, and the orbiting scroll 12 is revolved to reduce the volume of the compression chamber so that the compression chamber is centered. To compress the refrigerant in the compression chamber.

  As shown in FIG. 4, between the fixed scroll plate-like spiral teeth 11b adjacent so as to divide the compression chamber between the winding start position PA on the center side of the fixed scroll plate-like spiral teeth 11b and the outer winding end position PB. A dividing wall 20 connected to each other is provided. Further, the orbiting scroll plate-like spiral tooth 12b is formed with a divided region E (see FIG. 7) that is divided so as not to interfere with the dividing wall 20 along with the revolving motion of the orbiting scroll 12 at a position corresponding to the dividing wall 20. . The dividing wall 20 forms an outer compression part 40 and an inner compression part 41. Further, as shown in FIGS. 5 to 7, the orbiting scroll plate-like spiral teeth 12 b are formed inside the inner compression portion 41 and the orbiting scroll plate-like spiral teeth 32 revolving in the outer compression portion 40 by forming the dividing region E. And orbiting scroll plate-like spiral teeth 33 revolving. Further, the fixed scroll plate-like spiral teeth 11 b have a fixed scroll plate-like spiral tooth 30 that forms the outer compression portion 40 by the dividing wall 20 and a fixed scroll plate-like spiral tooth 31 that forms the inner compression portion 41. .

  A low-pressure refrigerant suction port 21 is formed at the outer winding end position of the orbiting scroll plate-like spiral tooth 32 in the outer compression unit 40 and connected to the low-pressure refrigerant suction pipe L1. Further, an intermediate pressure refrigerant discharge port 23 for discharging the intermediate pressure refrigerant RM3 compressed in the outer compression section 40 to the intermediate pressure chamber 16 is formed at the winding start position of the orbiting scroll plate-like spiral teeth 32 in the outer compression section 40. The Further, an intermediate pressure refrigerant suction port 22 that sucks the intermediate pressure refrigerants RM1 and RM3 through the intermediate pressure chamber 16 is formed at the outer winding end position of the orbiting scroll plate-like spiral teeth 33 in the inner compression portion 41. A high-pressure refrigerant discharge port 24 is formed at the inner winding start position, that is, at the center of the orbiting scroll plate-like spiral tooth 33 in the inner compression portion 41. The high-pressure refrigerant discharge port 24 communicates with the high-pressure chamber 17 via the discharge valve 18 and discharges the high-pressure refrigerant RH compressed by the inner compression portion 41 to the outside via the high-pressure refrigerant discharge pipe L3.

  Here, since the refrigerant circulation amount sucked into the inner compression portion 41 is larger than the refrigerant circulation amount sucked into the outer compression portion 40, the fixed scroll plate-like spiral teeth forming the inner compression portion 41 as shown in FIG. 31 and the height h2 of the orbiting scroll plate-like spiral teeth 33 are set higher than the height h1 of the fixed scroll plate-like spiral teeth 30 and the orbiting scroll plate-like spiral teeth 32 forming the outer compression portion 40. By adjusting the heights h1 and h2, the compression volume of the inner compression part 41 can be made larger than the compression volume of the outer compression part 40. As a result, the intermediate-pressure refrigerant expanded by the high-stage expansion valve is introduced into the high-stage compression mechanism, and the refrigerant circulation amount introduced into the high-stage compression mechanism is larger than the refrigerant circulation amount introduced into the low-stage compression mechanism. Even so, the apparatus can be downsized with a simple configuration.

  As shown in FIG. 5, tip seals 51 and 52 are provided on the distal end side of the fixed scroll plate-like spiral tooth 11b and the distal end side of the orbiting scroll plate-like spiral tooth 12b, respectively. During compression by the inner compression portion 41, refrigerant leakage between the outside and the inside of the fixed scroll plate-like spiral teeth 11b and refrigerant leakage between the outside and the inside of the orbiting scroll plate-like spiral teeth 12b are prevented.

[Embodiment 2]
(Application of asymmetric scroll compressor structure)
By the way, as shown in FIG. 8, in the scroll compressor 2 according to the second embodiment, the winding end position PB10 of the fixed scroll 11 and the winding end position PB11 of the orbiting scroll 12 are centered (position of the high-pressure refrigerant discharge port 24). Are arranged symmetrically.

  For this reason, as shown in FIG. 8A, in the outer compression section 40, the low-pressure refrigerant RL is first supplied to the first inner compression chamber 60-1 inside the orbiting scroll 12 and the first outer outside the orbiting scroll 12. The compression chamber 61-1 is formed. On the other hand, after one rotation (360 °) of the orbiting scroll 12, the first inner compression chamber 60-1 becomes the compressed second inner compression chamber 60-2, and the first outer compression chamber 61-1 becomes the compressed first. 2 becomes the outer compression chamber 61-2. That is, the first inner compression chamber 60-1 and the first outer compression chamber 61-1 show the state before one rotation of the second inner compression chamber 60-2 and the second outer compression chamber 61-2, respectively.

  FIG. 8B shows a state in which the orbiting scroll 12 has rotated from the state of FIG. 8A by the communication angle θA at which the second inner compression chamber 60-2 communicates with the intermediate pressure refrigerant discharge port 23. In this case, the intermediate pressure refrigerant in the second inner compression chamber 60-2 communicates with and discharges from the intermediate pressure refrigerant discharge port 23, and at the same time, communicates with the first outer compression chamber 61-1, as indicated by the arrow A1. The compressed intermediate pressure refrigerant in the second inner compression chamber 60-2, which has a relatively higher pressure than the outer compression chamber 61-1, leaks into the first outer compression chamber 61-1. As a result, recompression loss occurs, and compression efficiency decreases.

  Therefore, as shown in FIG. 9, the winding end position PB20 of the fixed scroll 11 and the winding end position PB21 of the orbiting scroll 12 are preferably arranged asymmetrically with respect to the center (position of the high-pressure refrigerant discharge port 24). Here, as shown in FIG. 9, in the asymmetric scroll compressor, the winding end position PB10 of the fixed scroll 11 in the symmetrical scroll compressor is set so that the extension angle θa from the winding end position PB10 is 0 ° <θa ≦ 180. Stretched at °. In FIG. 9, the winding end position PB20 is set so that the extension angle θa is 180 °.

Here, each inner wall and each outer wall of the fixed scroll 11 and the orbiting scroll 12 form an involute curve LI. The involute curve LI is a plane curve whose normal is always in contact with a certain circle (basic circle C). As shown in FIG. 10, assuming that the extension angle of the involute curve LI is θ (°) and the radius of the basic circle C is R, the position PB (θ) = {PBx (θ), PBy (θ) on the involute curve L1. )} Can be expressed by the following equation.
PBx (θ) = R {cos θ + (θ × π / 180) sin θ}
PBy (θ) = R {sin θ− (θ × π / 180) cos θ}
Therefore, the above-described expansion angle θa is θa = θ2−θ1, where the expansion angle at the winding end position PB10 is θ1 and the expansion angle at the winding end position PB20 is θ2. In other words, the winding end position PB20 is extended from the winding end position PB10 by an amount corresponding to the extension angle θa.

  FIG. 9 shows an asymmetric scroll compressor in which the winding end position PB20 of the fixed scroll 11 and the winding end position PB21 of the orbiting scroll 12 are arranged at the same angular position with respect to the symmetrical scroll compressor shown in FIG. It is what was made. In the arrangement of the asymmetric scroll compressor, when the first inner compression chamber 60-1 and the first outer compression chamber 61-1 shown in FIG. 8A are formed, the outer compression chamber 61 before half rotation is formed. -0 has already been formed. The outer compression chamber 61-0 becomes the first outer compression chamber 61-1 after one rotation. That is, when the first inner compression chamber 60-1 is formed, the first outer compression chamber 61-1 is already compressed from the half cycle before. Therefore, when the communication angle θA shown in FIG. 8B is obtained, the pressure in the first outer compression chamber 61-1 is substantially the same as the pressure in the second inner compression chamber 60-2, and the second inner compression chamber 61-2 is compressed. The amount of the intermediate pressure refrigerant compressed in the chamber 60-2 leaks into the first outer compression chamber 61-1. As a result, the recompression loss is reduced, and a reduction in compression efficiency can be prevented.

  FIG. 11 is a diagram comparing the pressure change between the inner compression chamber and the outer compression chamber and the pressure difference at the communication angle θA between the symmetric scroll compressor shown in FIG. 8 and the asymmetric scroll compressor shown in FIG. is there. The characteristic curves L60-1, L60-2, L61-0, L61-1, and L61-2 are the first inner compression chamber 60-1, the second inner compression chamber 60-2, the outer compression chamber 61-0, and the first, respectively. The pressure change of the 1st outer side compression chamber 61-1 and the 2nd outer side compression chamber 61-2 is shown. As shown in FIG. 11 (b), in the asymmetric scroll compressor, the outer compression chamber 61-, which becomes the first outer compression chamber 61-1, from the rotation angle θ1 before one rotation at which the rotation angle becomes 0 °. Since 0 is compressed, the pressure at the beginning (rotation angle 0 °) of the first outer compression chamber 61-1 is raised and increased, and the pressure difference PR 2 at the communication angle θA is shown in FIG. The pressure difference ΔPR is smaller than the pressure difference PR1 of the symmetric scroll compressor shown in FIG.

  As a result, as shown in FIG. 12, the recompression loss S2 of the asymmetric scroll compressor is smaller than the repressure loss S1 of the symmetric scroll compressor.

  The configuration of the asymmetric scroll compressor can be applied not only to the two-stage compression / two-stage expansion cycle shown in the first embodiment, but also to the two-stage compression / one-stage expansion cycle. Specifically, the height h2 of the fixed scroll plate-like spiral teeth 31 and the orbiting scroll plate-like spiral teeth 33 forming the inner compression portion 41 is set as the fixed scroll plate-like spiral teeth 30 and the orbiting scroll forming the outer compression portion 40. A configuration in which the height of the plate-like spiral teeth 32 is higher than the height h1 may not be adopted.

[Embodiment 3]
(Refrigerant leakage prevention mechanism)
Incidentally, the intermediate pressure chamber 16 has an intermediate pressure PM in the housing 10. When the pressure in the housing 10 is set to the intermediate pressure PM, the intermediate pressure PM is applied to the back surface of the orbiting scroll 12, so that the thrust load of the orbiting scroll 12 is reduced, and mechanical loss is reduced and wear of the thrust bearing 14 is reduced. The reliability of the scroll compressor 2 can be improved.

  However, as shown in FIG. 13, the orbiting scroll plate-like spiral teeth 12b of the orbiting scroll 12 receive a load in the radial direction A2, so that the orbiting scroll 12 is in a motion state that swings due to revolution with a slight inclination. There is a case. In this case, a gap d is generated between the distal end surface of the outer peripheral portion of the fixed scroll 11 on the side of the orbiting scroll 12 and the upper surface of the base plate 12 a of the orbiting scroll 12. When this gap d occurs, the intermediate pressure refrigerant RM in the intermediate pressure chamber 16 leaks to the outer compression section 40 that compresses the low pressure refrigerant RL. The leakage of the intermediate pressure refrigerant RM to the outer compression unit 40 decreases the compression efficiency of the outer compression unit 40.

  As shown in FIG. 14, the compression efficiency of the outer compression unit 40 is reduced because the pressure of the outer compression unit 40 increases due to the increase in the intermediate pressure refrigerant RM in the outer compression unit 40 and the compression power for the region E10 increases. It is. Further, as shown in FIG. 15, when the intermediate pressure refrigerant having a temperature higher than that of the low pressure refrigerant in the outer compression unit 40 leaks to the outer compression unit 40, the low pressure refrigerant is heated as indicated by an arrow A <b> 10 and compressed by the outer compression unit 40. The intermediate pressure refrigerant thus produced becomes higher in temperature than the ideal intermediate pressure refrigerant as indicated by an arrow A11. When this high-temperature intermediate pressure refrigerant is introduced into the inner compression portion 41, the density of the intermediate pressure refrigerant in the inner compression portion 41 decreases, so that the volume efficiency of the inner compression portion 41 decreases.

  For this reason, in the third embodiment, as shown in FIG. 13, the fixed scroll 11 is formed with an outer wall 11c having a U-shaped cross section in the axial direction of the orbiting scroll 12, and the front end surface of the outer wall 11c and the orbiting scroll. A ring-shaped seal is provided on the sliding surface with the 12 base plates 12a. In FIG. 16 and FIG. 17, the ring-shaped seal 70 is provided on the distal end surface side of the outer wall 11c.

  The ring-shaped seal 70 may be provided on the base plate 12a side of the orbiting scroll 12, as shown in FIG. The shape of the ring-shaped seal 70 is not limited to a circle, and may be an ellipse or a polygon according to the usage pattern.

(Thermal expansion absorbing part of the ring seal)
By the way, the ring-shaped seal 70 is formed of, for example, resin or metal. However, the ring-shaped seal 70 undergoes thermal expansion due to a temperature rise accompanying the operation of the scroll compressor 2. In particular, the ring-shaped seal 70 has a longer circumference than the width and thickness, and during thermal expansion, the circumferential extension is placed and restrained in the groove, so that thermal stress is generated, and further in the axial direction. There is a case where the deformation due to the deformation of the material causes damage.

  For this reason, it is preferable to provide the ring-shaped seal 70 with a thermal expansion absorbing portion that absorbs thermal expansion during thermal expansion. For example, as shown in FIG. 19, a split gap 71 is provided in part of the ring-shaped seal 70 as a clearance for thermal expansion. The division gap 71 in FIG. 19 is inclined with respect to the axial direction of the orbiting scroll 12. Here, the circumferential width d10 of the division gap 71 is a value corresponding to the amount of thermal expansion during thermal expansion. Moreover, since the division | segmentation gap 71 is restrained by a groove | channel, it is preferable to provide with two or more in the circumferential direction. By providing the dividing gap 71, it is possible to avoid the curling at the time of thermal expansion and to reliably block the refrigerant leakage.

  Further, as shown in FIG. 20, a division gap 72 may be provided instead of the division gap 71. The division gap 72 is inclined with respect to the circumferential direction of the orbiting scroll 12 or the fixed scroll 11. Here, the circumferential width d20 of the dividing gap 72 is a value corresponding to the amount of thermal expansion during thermal expansion. Moreover, since the division | segmentation gap 72 is restrained by a groove | channel, it is preferable to provide with two or more in the circumferential direction. By providing the dividing gap 72, it is possible to avoid the curling at the time of thermal expansion, and it is possible to reliably block the refrigerant leakage.

  Furthermore, as shown in FIG. 21, it is formed not in the divided gaps 71 and 72 but in the region sandwiched between the outer peripheral surface 70a and the inner peripheral surface 70b of the ring-shaped seal 70 and not including the outer peripheral surface 70a and the inner peripheral surface 70b. One or more space portions 73 may be provided. This space portion 73 absorbs thermal expansion due to the collapse of the space portion 73 during thermal expansion, suppresses deformation of the outer shape of the ring-shaped seal 70, and more reliably leaks refrigerant than a ring-shaped seal having a split gap. Can be blocked.

  The third embodiment can also be applied to a general scroll compressor other than the two-stage compression scroll compressor shown in the first embodiment. For example, the present invention can also be applied to a one-stage compression scroll compressor.

(Applicable heat cycle example)
In Embodiments 1 to 3 described above, the thermal cycle system shown in FIGS. 1 and 2 is shown as an example of a thermal cycle system that employs a two-stage compression and two-stage expansion cycle. However, the scroll compressor 2 shown in the first to third embodiments can be applied to a heat cycle system other than the heat cycle system shown in FIGS.

  For example, as shown in FIGS. 22 and 23, the supercooler 4 may be omitted from the thermal cycle system 1 shown in FIG.

  Further, as shown in FIGS. 24 and 25, in the thermal cycle system of FIGS. 22 and 23, the intermediate pressure refrigerant RM2 separated by the gas-liquid separator 6 and the low-pressure refrigerant RL derived from the evaporator 8 are used. An internal heat exchanger 9 that performs heat exchange may be provided.

  Further, as shown in FIGS. 26 and 27, in the thermal cycle system of FIGS. 1 and 2, the high-pressure refrigerant RH just before being introduced into the high stage expansion valve 5 and the low-pressure refrigerant RL derived from the evaporator 8 You may make it provide the internal heat exchanger 9a which heat-exchanges between.

  Further, as shown in FIGS. 28 and 29, the gas-liquid separator 6 of the thermal cycle system 1 shown in FIG. 1 is deleted, and the high-pressure refrigerant RH derived from the supercooler 4 is branched at the branch point PS. One of the branched high-pressure refrigerants RH is introduced into the intermediate expansion valve 5a and decompressed and expanded, and an internal heat exchanger performs heat exchange between the decompressed and expanded intermediate-pressure refrigerant and the other high-pressure refrigerant that is not decompressed and expanded. 9b is provided. The internal heat exchanger 9b uses the heat of the other high-pressure refrigerant that is not decompressed and expanded to heat the adiabatic-expanded intermediate-pressure refrigerant. This intermediate-pressure refrigerant is introduced into the high-stage compression chamber of the scroll compressor 2 as it is. On the other hand, the high-pressure refrigerant that is not adiabatically expanded via the internal heat exchanger 9b is introduced into the low-stage expansion valve 7 and expanded under reduced pressure to become an intermediate-pressure refrigerant.

  In addition, when heating using the condenser 3 mentioned above, a thermal cycle system becomes a heat pump system, and when cooling using the evaporator 8, a thermal cycle system becomes a normal refrigeration system.

  Moreover, although the scroll compressor 2 mentioned above was a two-stage compressor which has the outer side compression part 40 and the inner side compression part 41, it is good not only as this but a multistage compressor.

DESCRIPTION OF SYMBOLS 1 Thermal cycle system 2 Scroll compressor 3 Condenser 4 Supercooler 5 High stage expansion valve 5a Intermediate expansion valve 6 Gas-liquid separator 7 Low stage expansion valve 8 Evaporator 9, 9a, 9b Internal heat exchanger 10, 10a, DESCRIPTION OF SYMBOLS 10b Case 11 Fixed scroll 11a, 12a Base plate 11b Fixed scroll plate-like spiral tooth 11c Outer wall 12 Orbiting scroll 12b Orbiting scroll plate-like spiral tooth 13 Crankshaft 14 Thrust bearing 15 Balance weight 16 Intermediate pressure chamber 17 High pressure chamber 18 Discharge valve 20 Partition wall 21 Low pressure refrigerant suction port 22 Intermediate pressure refrigerant suction port 23 Intermediate pressure refrigerant discharge port 24 High pressure refrigerant discharge port 30, 31 Fixed scroll plate-like spiral teeth 32, 33 Orbiting scroll plate-like spiral teeth 40 Outer compression portion 41 Inner compression portion 51, 52 Tip seal 60-1 First inner compression chamber 60-2 Second inner pressure Chamber 61-0 Outer compression chamber 61-1 First outer compression chamber 61-2 Second outer compression chamber 70 Ring-shaped seal 70a Outer peripheral surface 70b Inner peripheral surface 71, 72 Dividing gap 73 Space portion AL Rotating direction d Gap E Dividing region GH, GL, GM Refrigerant circulation amount L1 Low-pressure refrigerant suction pipe L2 Intermediate-pressure refrigerant suction pipe L3 High-pressure refrigerant discharge pipe θA Communication angle

Claims (14)

A scroll compressor that compresses the refrigerant in the compression chamber by reciprocating the orbiting scroll plate-like spiral teeth by forming a compression chamber by meshing the fixed scroll plate-like spiral teeth and the orbiting scroll plate-like spiral teeth. And
A dividing wall that divides the compression chamber into an outer compression portion and an inner compression portion between a winding start on the center side of the fixed scroll plate-like spiral teeth and an outer winding end;
The orbiting scroll plate-like spiral teeth form a divided region at a position corresponding to the dividing wall so as not to interfere with the dividing wall with the revolution movement,
The heights of the fixed scroll plate-like spiral teeth and the orbiting scroll plate-like spiral teeth forming the inner compression portion are the heights of the fixed scroll plate-like spiral teeth and the orbiting scroll plate-like spiral teeth forming the outer compression portion. A scroll compressor characterized by being higher than its height. The outer compression section has an outer suction port that sucks in a low-pressure refrigerant, and an outer discharge port that compresses and discharges the refrigerant sucked from the outer suction port to an intermediate pressure,
The inner compression section includes an inner suction port that sucks refrigerant discharged from the outer discharge port and refrigerant introduced from the outside, and an inner discharge port that compresses and discharges the refrigerant sucked from the inner suction port to a high pressure. The scroll compressor according to claim 1, further comprising:   The outer scroll end position of the fixed scroll plate-like spiral tooth is characterized in that the extension angle θa from the winding end position of the fixed scroll plate-like spiral tooth in the symmetrical scroll is extended at 0 ° <θa ≦ 180 °. The scroll compressor according to claim 1 or 2.   The fixed scroll plate-like spiral teeth and the orbiting scroll plate-like spiral teeth are each erected on a base plate, and one of the base plates is formed with an outer wall that slides on the other base plate, and the tip of the outer wall The scroll compressor according to any one of claims 1 to 3, wherein a ring-shaped seal is provided on a sliding surface between the first base plate and the other base plate.   The scroll compressor according to claim 4, wherein the ring-shaped seal has a thermal expansion absorbing portion that absorbs thermal expansion.   The scroll compressor according to claim 5, wherein the thermal expansion absorption part is one or more divided gaps inclined with respect to an axial direction of the revolving motion.   The scroll compressor according to claim 5, wherein the thermal expansion absorption part is one or more divided gaps inclined with respect to a circumferential direction of the ring-shaped seal.   The scroll compressor according to claim 5, wherein the thermal expansion absorption part is one or more space parts formed in a region sandwiched between an outer peripheral surface and an inner peripheral surface of the ring-shaped seal. A scroll compressor according to claims 1-8;
A condenser that condenses the high-pressure refrigerant compressed by the scroll compressor;
A high stage expansion valve that decompresses and expands the refrigerant condensed by the condenser to an intermediate pressure;
A gas-liquid separator that gas-liquid separates the intermediate-pressure refrigerant introduced from the high-stage expansion valve and introduces gas into the inner compression section as an intermediate-pressure refrigerant of the scroll compressor;
A low-stage expansion valve that decompresses and expands the liquid in the gas-liquid separator as an intermediate-pressure refrigerant;
An evaporator that evaporates the low-pressure refrigerant introduced from the low-stage expansion valve and introduces it into the outer compression section as the low-pressure refrigerant of the scroll compressor;
A heat cycle system characterized by comprising:   The thermal cycle system according to claim 9, wherein a supercooler is provided between the condenser and the high stage expansion valve.   The heat cycle system according to claim 9 or 10, further comprising a heat exchanger for performing heat exchange between the refrigerant derived from the gas-liquid separator and the refrigerant derived from the evaporator.   The heat cycle system according to claim 9 or 10, further comprising a heat exchanger that performs heat exchange between the refrigerant immediately before being introduced into the high stage expansion valve and the refrigerant derived from the evaporator. . A scroll compressor according to claims 1-8;
A condenser that condenses the high-pressure refrigerant compressed by the scroll compressor;
An intermediate expansion valve that branches the refrigerant condensed by the condenser at a branch point, and decompresses and expands one of the branched refrigerants to an intermediate pressure;
The intermediate pressure refrigerant introduced from the intermediate expansion valve exchanges heat with another high pressure refrigerant branched at the branch point, and the heat exchanged intermediate pressure refrigerant is used as the intermediate pressure refrigerant of the scroll compressor. A heat exchanger introduced into the inner compression section as
An expansion valve that generates a low-pressure refrigerant by decompressing and expanding the high-pressure refrigerant heat-exchanged in the heat exchanger;
An evaporator that evaporates the low-pressure refrigerant introduced from the expansion valve and introduces it into the outer compression section as the low-pressure refrigerant of the scroll compressor;
A heat cycle system characterized by comprising:   The thermal cycle system according to claim 13, wherein a supercooler is provided between the condenser and the branch point.

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