EP3842640B1 - Multi-stage compressor - Google Patents
Multi-stage compressor Download PDFInfo
- Publication number
- EP3842640B1 EP3842640B1 EP19863099.8A EP19863099A EP3842640B1 EP 3842640 B1 EP3842640 B1 EP 3842640B1 EP 19863099 A EP19863099 A EP 19863099A EP 3842640 B1 EP3842640 B1 EP 3842640B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- pressure refrigerant
- medium
- chamber
- pressure
- stage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000003507 refrigerant Substances 0.000 claims description 313
- 230000006835 compression Effects 0.000 claims description 204
- 238000007906 compression Methods 0.000 claims description 204
- 230000006698 induction Effects 0.000 claims description 12
- 230000007246 mechanism Effects 0.000 description 23
- 238000000926 separation method Methods 0.000 description 22
- 238000010586 diagram Methods 0.000 description 15
- 239000007788 liquid Substances 0.000 description 10
- 238000005192 partition Methods 0.000 description 9
- 238000004891 communication Methods 0.000 description 5
- 230000002093 peripheral effect Effects 0.000 description 5
- 238000004781 supercooling Methods 0.000 description 4
- 238000004804 winding Methods 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
- F04C18/02—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents
- F04C18/0207—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents both members having co-operating elements in spiral form
- F04C18/0215—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents both members having co-operating elements in spiral form where only one member is moving
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
- F04C18/02—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents
- F04C18/0207—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents both members having co-operating elements in spiral form
- F04C18/0246—Details concerning the involute wraps or their base, e.g. geometry
- F04C18/0269—Details concerning the involute wraps
- F04C18/0276—Different wall heights
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C23/00—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids
- F04C23/001—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids of similar working principle
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C27/00—Sealing arrangements in rotary-piston pumps specially adapted for elastic fluids
- F04C27/005—Axial sealings for working fluid
Definitions
- the present invention relates to a multi-stage compressor with a multi-stage compression mechanism, the multi-stage compressor capable of achieving compactness of a system with an uncomplicated configuration even when an amount of circulating refrigerant introduced to a low-stage compression mechanism differs from that introduced to a high-stage compression mechanism.
- Compressors including a two-stage compression mechanism inside one scroll compressor have been conventionally known.
- Japanese Laid-open Patent Publication No. 2004-332556 discloses a two-stage compression scroll compressor that is provided with a land portion for dividing a compression chamber of a fixed scroll into two stages, that forms a low-stage compression mechanism and a high-stage compression mechanism respectively on the outer periphery and the inner periphery, which are divided by the land, and that introduces air compressed by the low-stage compression mechanism to the high-stage compression mechanism.
- JP 2017 031887 A describes a scroll compressor, which 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.
- An orbital scroll plate-shaped spiral tooth 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 of a fixed scroll plate-shaped spiral tooth and an orbital scroll plate-shaped spiral tooth, which form the inner compression part is set higher than a height of a fixed scroll plate-shaped spiral tooth and an orbital scroll plate-shaped spiral tooth, which form the outer compression part.
- JP 2018 028313 A describes a scroll compressor, in which a division wall for dividing a compression chamber into an outside compression part and an inside compression part between a center-side winding start and an outside winding end of fixed-scroll plate-shaped spiral teeth is arranged, and turning-scroll plate-shaped spiral teeth are divided so as not to interfere with a division wall accompanied by a revolution motion.
- An intermediate refrigerant discharge port for compressing a refrigerant which is sucked from a low-pressure refrigerant suction port to intermediate pressure, and discharging it is arranged so as to possess an opening at the division wall side of a fixed-scroll side slide face at which tip sides of the turning scroll plate-shaped spiral teeth slide in the outside compression part, and the opening has a center of gravity at the inside rather than a center line in a width direction of the fixed-scroll side slide face.
- the circulating refrigerant compressed in the low-stage compression mechanism is compressed in the high-stage compression mechanism as it is.
- medium-pressure refrigerant expanded by a high-stage expansion valve is introduced into the high-stage compression mechanism. Consequently, the amount of circulating refrigerant introduced to the high-stage compression mechanism becomes larger than the amount of circulating refrigerant introduced to the low-stage compression mechanism, and this makes it difficult to achieve two-stage compression.
- Achieving this two-stage compression two-stage expansion cycle needs a pair of scroll compressors constituted of a low-stage scroll compressor and a high-stage scroll compressor. Accordingly, a two-stage compression two-stage expansion cycle scroll compressor increases in size and has a complex layout of tubes.
- the present invention aims to provide a multi-stage compressor having a large number of valves, openings, and tubes, which are specific to the two-stage compression, arranged in an integrated manner so as to improve the maintainability and compactness of the multi-stage compressor.
- a multi-stage compressor includes: a plurality of compression chambers formed in a housing; a medium-pressure refrigerant discharge port that discharges medium-pressure refrigerant from a low-stage compression chamber of the compression chambers; a medium-pressure refrigerant suction port that is open in a same direction as the medium-pressure refrigerant discharge port and induces the medium-pressure refrigerant into a high-stage side of the compression chambers; a high-pressure refrigerant discharge port that is open in a same direction as the medium-pressure refrigerant discharge port and discharges high-pressure refrigerant discharged from a high-stage compression chamber of the compression chambers; and a refrigerant connection cover that is detachably mounted on the housing, wherein the refrigerant connection cover forms a medium-pressure refrigerant chamber, which communicates with the medium-pressure refrigerant suction port and the medium-pressure refrigerant discharge port and which has an external medium-pressure refrigerant connection
- the housing has a housing medium-pressure refrigerant suction port that is open in a same direction as the medium-pressure refrigerant discharge port and that discharges medium-pressure refrigerant through a seal in the housing, and the medium-pressure refrigerant suction port and the external medium-pressure refrigerant connection induction port are connected with each other with a tube.
- a high-pressure relief unit that allows the high-stage compression chamber and the high-pressure refrigerant chamber to communicate with each other when an inner pressure of the high-stage compression chamber becomes equal to or greater than a predetermined value is provided in the high-pressure refrigerant chamber of the housing.
- a medium-pressure relief unit that allows the low-stage compression chamber and the medium-pressure refrigerant chamber to communicate with each other when an inner pressure of the low-stage compression chamber becomes equal to or greater than a predetermined value is provided in the medium-pressure refrigerant chamber of the housing.
- a check valve for preventing circulating back to the low-stage compression chamber through the medium-pressure refrigerant discharge port is provided in the medium-pressure refrigerant chamber of the housing.
- a check valve for preventing circulating back to the high-stage compression chamber through the high-pressure refrigerant discharge port is provided in the high-pressure refrigerant chamber of the housing.
- a capacity of the medium-pressure refrigerant chamber is larger than a capacity of the high-pressure refrigerant chamber.
- a cross-sectional area of the medium-pressure refrigerant chamber is larger than a cross-sectional area of the high-pressure refrigerant chamber, with a depth of the medium-pressure refrigerant chamber being the same as a depth of the high-pressure refrigerant chamber.
- a depth of the medium-pressure refrigerant chamber is larger than a depth of the high-pressure refrigerant chamber.
- a notch for positioning is formed on the refrigerant connection cover.
- the multi-stage compressor is used for a two-stage compression two-stage expansion thermal cycle system.
- valves, openings, and tubes which are specific to two-stage compression, are arranged in an integrated manner so as to be able to improve the maintainability and compactness of the multi-stage compressor.
- FIG. 1 is a circuit diagram that illustrates a schematic configuration of a thermal cycle system 1 that uses a scroll compressor 2, which is a multi-stage compressor of a first example not falling under the scope of the claims.
- FIG. 2 is a p-h diagram of the thermal cycle system 1 of FIG. 1 .
- the scroll compressor 2 is a two-stage compressor and is an example multi-stage compressor.
- the thermal cycle of the thermal cycle system 1 is particularly a two-stage compression two-stage expansion cycle.
- a high-stage compression chamber of the scroll compressor 2 generates a high-pressure refrigerant RH of circulating refrigerant amount GH and introduces the refrigerant to a condenser 3 (from point P2 to point P3 of FIG. 2 ).
- the high-pressure refrigerant RH is condensed by the condenser 3 and rejects heat thereof.
- the high-pressure refrigerant RH is then supercooled by a supercooling device 4 (from point P3 to point P4 of FIG. 2 ).
- the high-pressure refrigerant RH is depressurized by a high-stage expansion valve 5 and expands (from point P4 to point P5 of FIG.
- a gaseous medium-pressure refrigerant RM1 which is vapor of the medium-pressure refrigerant RM, is introduced to the high-stage compression chamber of the scroll compressor 2 (point P2 of FIG. 2 ).
- a liquid medium-pressure refrigerant RM2 of the medium-pressure refrigerant RM is depressurized by a low-stage expansion valve 7 and expands and turns into a low-pressure refrigerant RL (from point P6 to point P7 of FIG. 2 ), and is introduced to an evaporator 8.
- the low-pressure refrigerant RL is evaporated by the evaporator 8 (from point P7 to point P1 of FIG. 2 ), and is introduced to a low-stage compression chamber of the scroll compressor 2 (point P1 of FIG. 2 ).
- the low-stage compression chamber of the scroll compressor 2 compresses the introduced low-pressure refrigerant RL into the medium-pressure refrigerant RM3.
- the high-stage compression chamber of the scroll compressor 2 compresses the medium-pressure refrigerants RM1 and RM3 into the high-pressure refrigerant RH.
- the low-stage compression chamber of the scroll compressor 2 receives circulating refrigerant amount GL in a liquid state separated by the gas-liquid separator 6.
- the high-stage compression chamber of the scroll compressor 2 receives circulating refrigerant amount GH the amount of which is the sum of circulating refrigerant amount GM in a gaseous state separated by the gas-liquid separator 6 and the circulating refrigerant amount GL introduced from the low-stage compression chamber.
- the amount of circulating refrigerant introduced to the high-stage compression chamber is therefore larger than that introduced to the low-stage compression chamber.
- FIG. 3 is a sectional view that illustrates the configuration of the scroll compressor 2.
- FIG. 4 is a sectional view along A-A line of FIG. 3 .
- FIG. 5 is a sectional view of a fixed scroll 11 and an orbiting scroll 12 illustrated in FIG. 3 .
- FIG. 6 is a perspective view of the fixed scroll 11 of FIG. 4 viewed from diagonally below.
- FIG. 7 is a perspective view of the orbiting scroll 12 of FIG. 4 viewed from diagonally above.
- the fixed scroll 11 and the orbiting scroll 12 form a later-described outer compression area 40, functioning as a low-pressure compression chamber, and a later-described inner compression area 41, functioning as a high-pressure compression chamber, and conduct two-stage compression.
- the fixed scroll 11 and the orbiting scroll 12 are arranged in a housing 10 including housings 10a and 10b.
- Two-stage compression is conducted with the orbiting scroll 12 making orbital motion with respect to the fixed scroll 11 in a rotational direction AL.
- a crankshaft 13 transfers torque from a rotary drive source (not illustrated) to the orbiting scroll 12.
- a thrust bearing 14 supports rotation of the orbiting scroll 12 in the thrust direction.
- a medium-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 orbital motion of the orbiting scroll 12.
- a low-pressure refrigerant suction tube L1 is a tube to introduce the low-pressure refrigerant RL into the outer compression area 40.
- a medium-pressure refrigerant suction tube L2 is a tube to introduce the medium-pressure refrigerant RM1 into the medium-pressure chamber 16.
- a high-pressure refrigerant discharge tube L3 is a tube to discharge the high-pressure refrigerant RH, discharged from the inner compression area 41 through a discharge valve 18 and the high-pressure chamber 17, outside the housing 10.
- the fixed scroll 11 includes fixed scroll plate-like spiral tooth 11b vertically arranged on a base plate 11a.
- the orbiting scroll 12 includes orbiting scroll plate-like spiral tooth 12b vertically arranged on a base plate 12a.
- the fixed scroll plate-like spiral tooth 11b of the fixed scroll 11 and the orbiting scroll plate-like spiral tooth 12b of the orbiting scroll 12 mesh with each other at respective front ends.
- This structure forms the outer compression area 40 and the inner compression area 41.
- compression chambers are formed outside and inside the orbiting scroll 12. With orbital motion of the orbiting scroll 12, the capacity of the compression chamber is reduced, and the compression chamber is shifted toward the center. This process compresses refrigerant in the compression chamber.
- a partition wall 20 is provided that connects the adjacent fixed scroll plate-like spiral tooth 11b so as to partition the compression chamber between a spiral start point PA in the center side of the fixed scroll plate-like spiral tooth 11b, and a spiral end point PB close to the outside.
- the orbiting scroll plate-like spiral tooth 12b has a separation area E (see FIG. 7 ) formed therein that splits the orbiting scroll plate-like spiral tooth 12b so as not to interfere with the partition wall 20 in accordance with orbital motion of the orbiting scroll 12 at a location corresponding to the partition wall 20.
- the partition wall 20 defines the outer compression area 40 and the inner compression area 41. As illustrated in FIG. 5 to FIG.
- providing the separation area E allows the orbiting scroll plate-like spiral tooth 12b to have an orbiting scroll plate-like spiral tooth 32 that orbits in the outer compression area 40 and an orbiting scroll plate-like spiral tooth 33 that orbits in the inner compression area 41.
- the partition wall 20 allows the fixed scroll plate-like spiral tooth 11b to have a fixed scroll plate-like spiral tooth 30 that forms the outer compression area 40 and a fixed scroll plate-like spiral tooth 31 that forms the inner compression area 41.
- a low-pressure refrigerant suction port 21 is formed and is connected with the low-pressure refrigerant suction tube L1. Furthermore, at the inner end of the spiral of the orbiting scroll plate-like spiral tooth 32 in the outer compression area 40, a medium-pressure refrigerant discharge port 23 is formed that discharges the medium-pressure refrigerant RM3 compressed in the outer compression area 40 to the medium-pressure chamber 16.
- a medium-pressure refrigerant suction port 22 is formed so as to be connected to the medium-pressure chamber 16 to suck the medium-pressure refrigerants RM1 and RM3. Furthermore, at an inner end, which is the center, of the spiral of the orbiting scroll plate-like spiral tooth 33 in the inner compression area 41, a high-pressure refrigerant discharge port 24 is formed.
- the high-pressure refrigerant discharge port 24 is connected to the high-pressure chamber 17 through the discharge valve 18, and discharges the high-pressure refrigerant RH compressed in the inner compression area 41 outside through the high-pressure refrigerant discharge tube L3.
- heights h2 of the fixed scroll plate-like spiral tooth 31 and the orbiting scroll plate-like spiral tooth 33 of the inner compression area 41 are set larger than heights h1 of the fixed scroll plate-like spiral tooth 30 and the orbiting scroll plate-like spiral tooth 32 of the outer compression area 40.
- the compression capacity of the inner compression area 41 can be larger than that of the outer compression area 40.
- tip seals 51 and 52 are attached to the respective front ends of the fixed scroll plate-like spiral tooth 11b and the orbiting scroll plate-like spiral tooth 12b.
- the tip seals 51 and 52 prevent the refrigerant from leaking between the outside and the inside of the fixed scroll plate-like spiral tooth 11b and from leaking between the outside and the inside of the orbiting scroll plate-like spiral tooth 12b during compression by the above-described outer compression area 40 and inner compression area 41.
- the scroll compressor 2 of a second example has a spiral end point PB10 of the fixed scroll 11 and a spiral end point PB11 of the orbiting scroll 12 symmetrically arranged with respect to the center (the location of the high-pressure refrigerant discharge port 24).
- first the low-pressure refrigerant RL forms a first inner compression chamber 60-1 inside the orbiting scroll 12 and a first outer compression chamber 61-1 outside the orbiting scroll 12. Meanwhile, a full turn (360°) of the orbiting scroll 12 changes the first inner compression chamber 60-1 into a compressed second inner compression chamber 60-2 and changes the first outer compression chamber 61-1 into a compressed second outer compression chamber 61-2.
- the first inner compression chamber 60-1 and the first outer compression chamber 61-1 have respective statuses of chambers before the full turn of the second inner compression chamber 60-2 and second outer compression chamber 61-2.
- FIG. 8(b) illustrates a state in which the orbiting scroll 12 of FIG. 8(a) has turned by a communication angle ⁇ A at which the second inner compression chamber 60-2 communicates with the medium-pressure refrigerant discharge port 23.
- the medium-pressure refrigerant in the second inner compression chamber 60-2 communicates with the medium-pressure refrigerant discharge port 23 and is discharged therefrom, and at the same time, communicates with the first outer compression chamber 61-1.
- the compressed medium-pressure refrigerant in the second inner compression chamber 60-2 the pressure of which is relatively higher than that of the first outer compression chamber 61-1, leaks into the first outer compression chamber 61-1. This leakage causes loss of recompression and thus reduces the efficiency of compression.
- a spiral end point PB20 of the fixed scroll 11 and a spiral end point PB21 of the orbiting scroll 12 be asymmetrically arranged with respect to the center (the location of the high-pressure refrigerant discharge port 24).
- This asymmetric-type scroll compressor as illustrated in FIG. 9 , has a spiral end point of the fixed scroll 11 moved by an involute roll angle ⁇ a in the range of 0° ⁇ ⁇ a ⁇ 180° from the spiral end point PB10 of the fixed scroll 11 of the symmetric-type scroll compressor.
- the spiral end point PB20 is such that the involute roll angle ⁇ a is 180°.
- the inner walls and the outer walls of the fixed scroll 11 and the orbiting scroll 12 form involute curves LI.
- the involute curve LI is a plane curve the normal of which is constantly in contact with a specific circle (a basic circle C).
- ⁇ a ⁇ 2 - ⁇ 1
- ⁇ 1 an involute roll angle of the spiral end point PB10
- ⁇ 2 an involute roll angle of the spiral end point PB20.
- the spiral end point PB20 is a point extended from the spiral end point PB10 by the involute roll angle ⁇ a.
- the asymmetric-type scroll compressor of FIG. 9 has the spiral end point PB20 of the fixed scroll 11 and the spiral end point PB21 of the orbiting scroll 12 located at the same angular position.
- an outer compression chamber 61-0 that is half turn behind has already been formed.
- the outer compression chamber 61-0 changes into the first outer compression chamber 61-1 after a full turn. In other words, when the first inner compression chamber 60-1 is formed, the first outer compression chamber 61-1 has been compressed since a half cycle before.
- the pressure of the first outer compression chamber 61-1 becomes substantially equal to the pressure of the second inner compression chamber 60-2. This reduces the amount of the medium-pressure refrigerant compressed in the second inner compression chamber 60-2 to be leaked into the first outer compression chamber 61-1. Accordingly, the loss of recompression decreases and a reduction in the efficiency of compression can be prevented.
- FIGS. 11 are diagrams for comparison between the symmetric-type scroll compressor of FIG. 8 and the asymmetric-type scroll compressor of FIG. 9 regarding changes in the pressure of the inner compression chamber and the outer compression chamber and a difference in the pressure therebetween at the communication angle ⁇ A.
- the characteristic curves L60-1, L60-2, L61-0, L61-1, and L61-2 indicate changes in the pressure of the first inner compression chamber 60-1, the second inner compression chamber 60-2, the outer compression chamber 61-0, the first outer compression chamber 61-1, and the second outer compression chamber 61-2, respectively.
- the asymmetric-type scroll compressor has a recompression loss S2 that is smaller than a recompression loss S1 of the symmetric-type scroll compressor.
- the configuration of the asymmetric-type scroll compressor is applicable to the two-stage compression two-stage expansion cycle of the first example and to a two-stage compression single-stage expansion cycle. Specifically, it is not necessary to employ a configuration in which the heights h2 of the fixed scroll plate-like spiral tooth 31 and the orbiting scroll plate-like spiral tooth 33 forming the inner compression area 41 is larger than the heights h1 of the fixed scroll plate-like spiral tooth 30 and the orbiting scroll plate-like spiral tooth 32 forming the outer compression area 40.
- the medium-pressure chamber 16 has medium pressure PM.
- the medium pressure PM is applied to the back surface of the orbiting scroll 12, which reduces the thrust load of the orbiting scroll 12. Reducing the mechanical loss and protecting the thrust bearing 14 from wearing can therefore enhance reliability of the scroll compressor 2.
- the orbiting scroll plate-like spiral tooth 12b of the orbiting scroll 12 receives load in a radial direction A2.
- the load may cause the orbiting scroll 12 to oscillate when orbiting at a small slant angle.
- a gap d is formed between the front end surface, closer to the orbiting scroll 12, of the outer peripheral portion of the fixed scroll 11 and the upper surface of the base plate 12a of the orbiting scroll 12.
- the gap d permits the medium-pressure refrigerant RM in the medium-pressure chamber 16 to leak into the outer compression area 40 where the low-pressure refrigerant RL is compressed. Leakage of the medium-pressure refrigerant RM into the outer compression area 40 reduces the efficiency of compression in the outer compression area 40.
- the compression efficiency in the outer compression area 40 is reduced, as illustrated in FIG. 14 , with an increase in the amount of the medium-pressure refrigerant RM in the outer compression area 40.
- the increase raises the pressure of the outer compression area 40, and power necessary for compression is increased by a region E10.
- the low-pressure refrigerant when the medium-pressure refrigerant, the temperature of which is higher than that of the low-pressure refrigerant in the outer compression area 40, leaks into the outer compression area 40, the low-pressure refrigerant is heated as indicated by an arrow A10.
- the temperature of the medium-pressure refrigerant compressed in the outer compression area 40 is accordingly increased relative to the temperature of ideal medium-pressure refrigerant, as indicated by an arrow A11.
- the high-temperature medium-pressure refrigerant introduced into the inner compression area 41 reduces the density of the medium-pressure refrigerant in the inner compression area 41, which reduces the volumetric efficiency of the inner compression area 41.
- the fixed scroll 11 has an outer wall 11c formed such that the sectional surface of the orbiting scroll 12 in the axial direction is in a U shape.
- An annular seal is disposed on a sliding surface between the front end surface of the outer wall 11c and the base plate 12a of the orbiting scroll 12.
- an annular seal 70 is mounted on the front end surface of the outer wall 11c.
- the annular seal 70 may be mounted on the base plate 12a of the orbiting scroll 12, as illustrated in FIG. 18 . Without being limited to a circular shape, the annular seal 70 may be oval, polygonal, or the like depending on the purpose.
- the annular seal 70 is made of resin, metal, or other materials.
- the annular seal 70 is subjected to thermal expansion with an increase in the temperature occurring upon operation of the scroll compressor 2.
- the annular seal 70 has a long circumferential length relative to the width and the thickness, and when being subjected to thermal expansion, the annular seal 70 is stretched in the circumferential direction to be constrained by the channel, causes thermal stress to occur, and also generates scuffing due to deformation in the axial direction, and thus may be broken.
- the annular seal 70 therefore preferably has a thermal expansion absorbing portion for absorbing thermal expansion on the occasion of thermal expansion.
- a separation gap 71 functioning as a clearance during thermal expansion is provided on a part of the annular seal 70.
- the separation gap 71 of FIG. 19 is slanted with respect to the axial direction of the orbiting scroll 12.
- a width d10 of the separation gap 71 in the circumferential direction is determined based on the amount of thermal expansion when thermal expansion occurs. Since the separation gap 71 is constrained by the channel, a plurality of the separation gaps 71 are preferably formed in the circumferential direction. Providing the separation gap 71 can prevent scuffing during thermal expansion and can certainly block leakage of refrigerant.
- the separation gap 71 may be replaced by a separation gap 72.
- the separation gap 72 is slanted with respect to the circumferential direction of the orbiting scroll 12 or the fixed scroll 11.
- a width d20 of the separation gap 72 in the circumferential direction is determined based on the amount of thermal expansion during thermal expansion. Since the separation gap 72 is constrained by the channel, a plurality of the separation gaps 72 are preferably formed in the circumferential direction. Formation of the separation gap 72 can prevent scuffing during thermal expansion and can certainly block leakage of refrigerant.
- the separation gaps 71 and 72 may be replaced by one or a plurality of hollow portions 73 formed in the area between, but not including, an outer peripheral surface 70a and an inner peripheral surface 70b of the annular seal 70.
- the hollow portion 73 breaks to absorb the thermal expansion, thereby reducing deformation of the outer shape of the annular seal 70.
- the hollow portion 73 can more certainly block leakage of refrigerant than an annular seal having a separation gap can.
- the third example is applicable to the two-stage compression scroll compressor of the above-described first example and, other than this, applicable to a common scroll compressor.
- the third example is applicable to a single-stage compression scroll compressor.
- the above first to third examples describe the thermal cycle system illustrated in FIG. 1 and FIG. 2 as an example thermal cycle system using a two-stage compression two-stage expansion cycle.
- the scroll compressor 2 of the first to the third examples is applicable to thermal cycle systems other than the thermal cycle system of FIG. 1 and FIG. 2 .
- the supercooling device 4 may be removed from the thermal cycle system 1 of FIG. 1 .
- an internal heat exchanger 9 may be provided to the thermal cycle system of FIG. 22 and FIG. 23 .
- the internal heat exchanger 9 transfers heat between the medium-pressure refrigerant RM2 separated by the gas-liquid separator 6 and the low-pressure refrigerant RL ejected from the evaporator 8.
- the thermal cycle system of FIG. 1 and FIG. 2 may include an internal heat exchanger 9a for transferring heat between the high-pressure refrigerant RH right before introduction to the high-stage expansion valve 5 and the low-pressure refrigerant RL ejected from the evaporator 8.
- the gas-liquid separator 6 included in the thermal cycle system 1 of FIG. 1 is removed, the high-pressure refrigerant RH ejected from the supercooling device 4 is branched at a separation point PS, one part of the branched high-pressure refrigerant RH is introduced into an intermediate expansion valve 5a, so as to be depressurized and expanded, and an internal heat exchanger 9b is provided that performs heat exchange between the depressurized and expanded medium-pressure refrigerant and the other part of the separated high-pressure refrigerant that is not depressurized and expanded.
- the internal heat exchanger 9b uses heat of the other part of the high-pressure refrigerant that is not depressurized and expanded to heat the depressurized and expanded medium-pressure refrigerant.
- the heated medium-pressure refrigerant is then directly introduced to the high-stage compression chamber of the scroll compressor 2. Meanwhile, the high-pressure refrigerant that is not depressurized and expanded passing the internal heat exchanger 9b is introduced into the low-stage expansion valve 7 and turns into medium-pressure refrigerant by being depressurized and expanded.
- FIG. 30 is a vertical sectional view of a scroll compressor 102 according to the invention
- FIG. 31 is a perspective view of the scroll compressor 102 of FIG. 30 viewed diagonally from the right.
- FIG. 32 is a perspective view of the scroll compressor 102 of FIG. 30 viewed diagonally from the left.
- FIG. 33 is a perspective view of a refrigerant connection cover 100 of FIG. 30 viewed from the back (in the Y direction) thereof.
- FIG. 34 is a front view with the refrigerant connection cover 100 mounted.
- FIG. 35 is a front view with the refrigerant connection cover 100 removed.
- a housing 10a including the medium-pressure chamber 16 and the high-pressure chamber 17 covers the back surface, facing outside, of the fixed scroll 11.
- the housing 10a is connected to the housing 10b.
- the refrigerant connection cover 100 including a medium-pressure refrigerant chamber 116 and a high-pressure refrigerant chamber 117 is directly mounted on the back surface facing the outside (in the Y direction) of the fixed scroll 11.
- the medium-pressure refrigerant chamber 116 sucks the medium-pressure refrigerants RM1 and RM3 and discharges a medium-pressure refrigerant RM4 into which the medium-pressure refrigerants RM1 and RM3 have been merged.
- the high-pressure refrigerant chamber 117 sucks and discharges the high-pressure refrigerant RH.
- the medium-pressure refrigerant chamber 116 and the high-pressure refrigerant chamber 117 that are formed between the refrigerant connection cover 100 and the fixed scroll 11 are each sealed with O-rings or similar members.
- a thrust bearing mechanism 114 includes a thrust bearing mechanism and a rotation control mechanism to control rotation of the orbiting scroll 12. More specifically, three units of the thrust bearing mechanisms 114 are disposed on the XZ plane.
- the refrigerant connection cover 100 is detachably mounted on the housing 10.
- the refrigerant connection cover 100 When the refrigerant connection cover 100 is directly mounted on the fixed scroll 11, the refrigerant connection cover 100 can be removed independently from the housing 10 (a housing 10c) including housings 10c and 10d, without being affected by the housing 10. This structure is therefore beneficial in maintainability and compactness. As illustrated in FIG. 30 , the housing 10c is fixed to the fixed scroll 11, and the fixed scroll 11 constitutes a part of the housing 10. Because the refrigerant connection cover 100 has no necessity of functioning as a housing, a number of valves, openings, and tubes necessary for two-stage compression, can be arranged in an integrated manner.
- the medium-pressure refrigerant chamber 116 includes a recess portion 105 of the fixed scroll 11 and a recess portion 106 of the refrigerant connection cover 100 that are facing each other.
- the high-pressure refrigerant chamber 117 includes a recess portion 107 of the fixed scroll 11 and a recess portion 108 of the refrigerant connection cover 100 that are facing each other.
- the medium-pressure refrigerant chamber 116 and the high-pressure refrigerant chamber 117 are partitioned from each other by a partition wall 101.
- the recess portion 105 has a medium-pressure refrigerant discharge port 123 corresponding to the medium-pressure refrigerant discharge port 23 communicating with the outer compression area 40, a medium-pressure refrigerant suction port 122 corresponding to the medium-pressure refrigerant suction port 22 communicating with the inner compression area 41, and an outlet opening 151 of a medium-pressure relief hole 141 communicating with the outer compression area 40.
- the recess portion 106 has an external medium-pressure refrigerant connection induction port 126 to suck gaseous medium-pressure refrigerant RM1 introduced from the external gas-liquid separator 6.
- the medium-pressure refrigerant RM1 is introduced into the housing 10d through an external medium-pressure refrigerant suction port 130 along with oil, and reaches a housing medium-pressure refrigerant suction port 131 through a seal in the housing 10.
- the housing medium-pressure refrigerant suction port 131 and the external medium-pressure refrigerant connection induction port 126 are connected with each other through an intermediate tube LM.
- the medium-pressure refrigerant RM1 sucked through the housing medium-pressure refrigerant suction port 131 is introduced to the medium-pressure refrigerant chamber 116 through the external medium-pressure refrigerant connection induction port 126.
- the intermediate tube LM (see FIG. 1 ) is a tube to introduce gaseous medium-pressure refrigerant RM1 separated by the gas-liquid separator 6 into the medium-pressure refrigerant chamber 116.
- the intermediate tube LM passes the housing 10 in the middle thereof.
- the fixed scroll 11 has a low-pressure refrigerant suction port 121 corresponding to the low-pressure refrigerant suction port 21.
- the low-pressure refrigerant RL is sucked into the outer compression area 40 through the low-pressure refrigerant suction port 121.
- the recess portion 107 has a high-pressure refrigerant discharge port 124 corresponding to the high-pressure refrigerant discharge port 24 and an outlet opening 152 of a high-pressure relief hole 142 communicating with the outer compression area 40.
- the recess portion 108 has a high-pressure refrigerant ejection port 125 to discharge the high-pressure refrigerant RH in the high-pressure refrigerant chamber 117 outside.
- the recess portion 105 of the medium-pressure refrigerant chamber 116 is provided with a check valve V1 for preventing the medium-pressure refrigerant RM3 from circulating back into the outer compression area 40 through the medium-pressure refrigerant discharge port 123.
- the recess portion 107 of the high-pressure refrigerant chamber 117 is provided with a check valve V2 for preventing the high-pressure refrigerant RH from circulating back into the inner compression area 41 through the high-pressure refrigerant discharge port 124.
- the recess portion 105 of the medium-pressure refrigerant chamber 116 is provided with a medium-pressure relief valve V11 serving as a medium-pressure relief unit, at the outlet opening 151 of the medium-pressure relief hole 141 (see FIG. 6 and FIG. 35 ) to control the pressure of refrigerant in the outer compression area 40 under a first predetermined pressure.
- the recess portion 107 of the high-pressure refrigerant chamber 117 is provided with a high-pressure relief valve V12, serving as a high-pressure relief unit, at the outlet opening 152 of a high-pressure relief hole 142 (see FIG. 6 and FIG. 35 ) to control the pressure of refrigerant in the inner compression area 41 under a second predetermined pressure.
- the medium-pressure refrigerant discharge port 123, the medium-pressure refrigerant suction port 122, and the high-pressure refrigerant discharge port 124 are arranged on the housing 10.
- the refrigerant connection cover 100 including an external medium-pressure refrigerant connection induction port 126 and a high-pressure refrigerant ejection port 125 is mounted on the housing 10, whereby the medium-pressure refrigerant chamber 116 and the high-pressure refrigerant chamber 117 are formed.
- the medium-pressure refrigerant suction port 122, the medium-pressure refrigerant discharge port 123, and the external medium-pressure refrigerant connection induction port 126 communicate with the medium-pressure refrigerant chamber 116.
- the high-pressure refrigerant discharge port 124 and the high-pressure refrigerant ejection port 125 communicate with a high-pressure refrigerant chamber 117.
- the medium-pressure refrigerant suction port 122 and the high-pressure refrigerant discharge port 124 are open in the same direction as the medium-pressure refrigerant discharge port 123.
- the housing medium-pressure refrigerant suction port 131 and the medium-pressure refrigerant discharge port 123 are open in the same direction to discharge medium-pressure refrigerant through a seal in the housing 10.
- the above medium-pressure relief valve V11, the high-pressure relief valve V12, the check valve V1, and the check valve V2 are exposed on the surface of the housing 10 when the refrigerant connection cover 100 is removed, whereby maintainability is enhanced.
- the medium-pressure refrigerant chamber 116 has a larger capacity than that of the high-pressure refrigerant chamber 117.
- the medium-pressure refrigerants RM1, RM3, and RM4 have smaller density than that of the high-pressure refrigerant RH and easily cause pressure loss.
- the medium-pressure refrigerant chamber 116 is increased in a capacity to reduce the pressure loss.
- the medium-pressure refrigerant chamber 116 has an increased capacity by making the cross-sectional area of the medium-pressure refrigerant chamber 116 larger than that of the high-pressure refrigerant chamber 117 with a depth d1 of the medium-pressure refrigerant chamber 116 being the same as a depth d2 of the high-pressure refrigerant chamber 117.
- the medium-pressure refrigerant chamber 116 may have an increased capacity by making the depth d1 of the medium-pressure refrigerant chamber 116 larger than the depth d2 of the high-pressure refrigerant chamber 117.
- the pressure of the medium-pressure refrigerant is smaller than that of the high-pressure refrigerant, and the refrigerant connection cover 100 is allowed to reduce the thickness of a portion around the medium-pressure refrigerant chamber 116, which makes it easy to increase the depth d2.
- the capacity of the medium-pressure refrigerant chamber 116 or the high-pressure refrigerant chamber 117 is to be changed, the capacity (the depth) of the recess portion 106 or the recess portion 108 formed on the refrigerant connection cover 100 is controlled.
- the capacity of the medium-pressure refrigerant chamber 116 or the high-pressure refrigerant chamber 117 can be thus changed without changing the structure of the housing 10 side.
- Notches 140 formed in the refrigerant connection cover 100 are used for positioning the refrigerant connection cover 100 to be mounted.
- the thermal cycle system is a heat pump system in the case of heating using the above-described condenser 3 and the thermal cycle system is an ordinary freezing system in the case of cooling using the evaporator 8.
- scroll compressor 2 is a two-stage compressor including the outer compression area 40 and the inner compression area 41, it is not limited thereto, and the scroll compressor 2 may be a multi-stage compressor.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Rotary Pumps (AREA)
- Applications Or Details Of Rotary Compressors (AREA)
Description
- The present invention relates to a multi-stage compressor with a multi-stage compression mechanism, the multi-stage compressor capable of achieving compactness of a system with an uncomplicated configuration even when an amount of circulating refrigerant introduced to a low-stage compression mechanism differs from that introduced to a high-stage compression mechanism.
- Compressors including a two-stage compression mechanism inside one scroll compressor have been conventionally known. For example,
Japanese Laid-open Patent Publication No. 2004-332556 -
JP 2017 031887 A -
JP 2018 028313 A - In the above-described two-stage compression scroll compressor, the circulating refrigerant compressed in the low-stage compression mechanism is compressed in the high-stage compression mechanism as it is. When the two-stage compression scroll compressor is to be applied for a two-stage compression two-stage expansion cycle compressor, medium-pressure refrigerant expanded by a high-stage expansion valve is introduced into the high-stage compression mechanism. Consequently, the amount of circulating refrigerant introduced to the high-stage compression mechanism becomes larger than the amount of circulating refrigerant introduced to the low-stage compression mechanism, and this makes it difficult to achieve two-stage compression. Achieving this two-stage compression two-stage expansion cycle needs a pair of scroll compressors constituted of a low-stage scroll compressor and a high-stage scroll compressor. Accordingly, a two-stage compression two-stage expansion cycle scroll compressor increases in size and has a complex layout of tubes.
- Considering the above-described fact, the present invention aims to provide a multi-stage compressor having a large number of valves, openings, and tubes, which are specific to the two-stage compression, arranged in an integrated manner so as to improve the maintainability and compactness of the multi-stage compressor.
- The above problem is solved and the above object is attained by a multi-stage compressor according to
claim 1.Claims 2 to 11 refer to specifically advantageous realizations of the multi-stage compressor according toclaim 1. - A multi-stage compressor according to an aspect of the present invention includes: a plurality of compression chambers formed in a housing; a medium-pressure refrigerant discharge port that discharges medium-pressure refrigerant from a low-stage compression chamber of the compression chambers; a medium-pressure refrigerant suction port that is open in a same direction as the medium-pressure refrigerant discharge port and induces the medium-pressure refrigerant into a high-stage side of the compression chambers; a high-pressure refrigerant discharge port that is open in a same direction as the medium-pressure refrigerant discharge port and discharges high-pressure refrigerant discharged from a high-stage compression chamber of the compression chambers; and a refrigerant connection cover that is detachably mounted on the housing, wherein the refrigerant connection cover forms a medium-pressure refrigerant chamber, which communicates with the medium-pressure refrigerant suction port and the medium-pressure refrigerant discharge port and which has an external medium-pressure refrigerant connection induction port that is open toward an outside wherein the refrigerant connection cover forms a high-pressure refrigerant chamber, which communicates with the high-pressure refrigerant discharge port and which has a high-pressure refrigerant ejection port open toward an outside,
wherein the multi-stage compressor is a scroll compressor including an orbiting scroll and a fixed scroll, and the fixed scroll constitutes a part of the housing, and the refrigerant connection cover is mounted on the fixed scroll, wherein the medium-pressure refrigerant chamber includes a recess portion of the fixed scroll and a recess portion of the refrigerant connection cover that are facing each other,wherein the high-pressure refrigerant chamber includes a recess portion of the fixed scroll and a recess portion of the refrigerant connection cover that are facing each other. - Further, in the multi-stage compressor according to an aspect of the present invention, the housing has a housing medium-pressure refrigerant suction port that is open in a same direction as the medium-pressure refrigerant discharge port and that discharges medium-pressure refrigerant through a seal in the housing, and the medium-pressure refrigerant suction port and the external medium-pressure refrigerant connection induction port are connected with each other with a tube.
- Further, in the multi-stage compressor according to an aspect of the present invention, a high-pressure relief unit that allows the high-stage compression chamber and the high-pressure refrigerant chamber to communicate with each other when an inner pressure of the high-stage compression chamber becomes equal to or greater than a predetermined value is provided in the high-pressure refrigerant chamber of the housing.
- Further, in the multi-stage compressor according to an aspect of the present invention, a medium-pressure relief unit that allows the low-stage compression chamber and the medium-pressure refrigerant chamber to communicate with each other when an inner pressure of the low-stage compression chamber becomes equal to or greater than a predetermined value is provided in the medium-pressure refrigerant chamber of the housing.
- Further, in the multi-stage compressor according to an aspect of the present invention, a check valve for preventing circulating back to the low-stage compression chamber through the medium-pressure refrigerant discharge port is provided in the medium-pressure refrigerant chamber of the housing.
- Further, in the multi-stage compressor according to an aspect of the present invention, a check valve for preventing circulating back to the high-stage compression chamber through the high-pressure refrigerant discharge port is provided in the high-pressure refrigerant chamber of the housing.
- Further, in the multi-stage compressor according to an aspect of the present invention, a capacity of the medium-pressure refrigerant chamber is larger than a capacity of the high-pressure refrigerant chamber.
- Further, in the multi-stage compressor according to an aspect of the present invention, a cross-sectional area of the medium-pressure refrigerant chamber is larger than a cross-sectional area of the high-pressure refrigerant chamber, with a depth of the medium-pressure refrigerant chamber being the same as a depth of the high-pressure refrigerant chamber.
- Further in the multi-stage compressor according to an aspect of the present invention, a depth of the medium-pressure refrigerant chamber is larger than a depth of the high-pressure refrigerant chamber.
- Further, in the multi-stage compressor according to an aspect of the present invention, a notch for positioning is formed on the refrigerant connection cover.
- Further, in the multi-stage compressor according to an aspect of the present invention, the multi-stage compressor is used for a two-stage compression two-stage expansion thermal cycle system.
- According to the present invention, a large number of valves, openings, and tubes, which are specific to two-stage compression, are arranged in an integrated manner so as to be able to improve the maintainability and compactness of the multi-stage compressor.
-
-
FIG. 1 is a circuit diagram that illustrates a schematic configuration of a thermal cycle system that uses a scroll compressor, which is a multi-stage compressor of a first example not falling under the scope of the claims. -
FIG. 2 is a p-h diagram of the thermal cycle system ofFIG. 1 . -
FIG. 3 is a sectional view that illustrates the configuration of the scroll compressor. -
FIG. 4 is a sectional view along A-A line ofFIG. 3 . -
FIG. 5 is a sectional view of a fixed scroll and an orbiting scroll illustrated inFIG. 3 . -
FIG. 6 is a perspective view of the fixed scroll ofFIG. 4 viewed from diagonally below. -
FIG. 7 is a perspective view of the orbiting scroll ofFIG. 4 viewed from diagonally above. -
FIGS. 8 is an illustrative drawing to illustrate compression operation of a symmetric-type scroll compressor. -
FIG. 9 is an illustrative drawing to explain compression operation of an asymmetric-type scroll compressor. -
FIG. 10 is an illustrative drawing to explain relation between a point on an involute curve and an involute roll angle. -
FIG. 11 is a diagram for comparison of compression operation of the symmetric-type scroll compressor and the asymmetric-type scroll compressor. -
FIG. 12 is an illustrative diagram to explain compression operation of the asymmetric-type scroll compressor that reduces the loss of recompression. -
FIG. 13 is a sectional view of a slanted orbiting scroll. -
FIG. 14 is an illustrative drawing to explain a reduction in the compression efficiency occurring at an outer compression area under the condition ofFIG. 13 . -
FIG. 15 is an illustrative drawing to explain a reduction in the volumetric efficiency occurring at an inner compression area under the condition ofFIG. 13 . -
FIG. 16 is a sectional view of an annular seal mounted on a front end surface of an outer wall of the fixed scroll. -
FIG. 17 is a sectional view of the scroll compressor with the annular seal, along B-B line ofFIG. 3 . -
FIG. 18 is a sectional view of the annular seal mounted on a base plate of the orbiting scroll. -
FIG. 19 is an example drawing of the annular seal having a separation gap. -
FIG. 20 is another example drawing of the annular seal having a separation gap. -
FIG. 21 is an example drawing of the annular seal having hollow portions. -
FIG. 22 is a circuit diagram that illustrates an example thermal cycle system. -
FIG. 23 is a p-h diagram of the thermal cycle system ofFIG. 22 . -
FIG. 24 is a circuit diagram that illustrates an example thermal cycle system. -
FIG. 25 is a p-h diagram of the thermal cycle system ofFIG. 24 . -
FIG. 26 is a circuit diagram that illustrates an example thermal cycle system. -
FIG. 27 is a p-h diagram of the thermal cycle system ofFIG. 26 . -
FIG. 28 is a circuit diagram that illustrates an example thermal cycle system. -
FIG. 29 is a p-h diagram of the thermal cycle system ofFIG. 28 . -
FIG. 30 is a vertical sectional view that illustrates the configuration of a scroll compressor of an embodiment of the invention. -
FIG. 31 is a perspective view of the scroll compressor ofFIG. 30 viewed diagonally from the right. -
FIG. 32 is a perspective view of the scroll compressor ofFIG. 30 viewed diagonally from the left. -
FIG. 33 is a perspective view of a refrigerant connection cover ofFIG. 30 viewed from the back thereof. -
FIG. 34 is a front view with the refrigerant connection cover mounted. -
FIG. 35 is a front view with the refrigerant connection cover removed. - Examples and an embodiment of the present invention will now be described with reference to the accompanying drawings.
- First example not falling under the scope of the claims
-
FIG. 1 is a circuit diagram that illustrates a schematic configuration of athermal cycle system 1 that uses ascroll compressor 2, which is a multi-stage compressor of a first example not falling under the scope of the claims.FIG. 2 is a p-h diagram of thethermal cycle system 1 ofFIG. 1 . Thescroll compressor 2 is a two-stage compressor and is an example multi-stage compressor. The thermal cycle of thethermal cycle system 1 is particularly a two-stage compression two-stage expansion cycle. - A high-stage compression chamber of the
scroll compressor 2 generates a high-pressure refrigerant RH of circulating refrigerant amount GH and introduces the refrigerant to a condenser 3 (from point P2 to point P3 ofFIG. 2 ). The high-pressure refrigerant RH is condensed by thecondenser 3 and rejects heat thereof. The high-pressure refrigerant RH is then supercooled by a supercooling device 4 (from point P3 to point P4 ofFIG. 2 ). The high-pressure refrigerant RH is depressurized by a high-stage expansion valve 5 and expands (from point P4 to point P5 ofFIG. 2 ) to be a medium-pressure refrigerant RM and is introduced to a gas-liquid separator 6. A gaseous medium-pressure refrigerant RM1, which is vapor of the medium-pressure refrigerant RM, is introduced to the high-stage compression chamber of the scroll compressor 2 (point P2 ofFIG. 2 ). A liquid medium-pressure refrigerant RM2 of the medium-pressure refrigerant RM is depressurized by a low-stage expansion valve 7 and expands and turns into a low-pressure refrigerant RL (from point P6 to point P7 ofFIG. 2 ), and is introduced to anevaporator 8. The low-pressure refrigerant RL is evaporated by the evaporator 8 (from point P7 to point P1 ofFIG. 2 ), and is introduced to a low-stage compression chamber of the scroll compressor 2 (point P1 ofFIG. 2 ). - The low-stage compression chamber of the
scroll compressor 2 compresses the introduced low-pressure refrigerant RL into the medium-pressure refrigerant RM3. The high-stage compression chamber of thescroll compressor 2 compresses the medium-pressure refrigerants RM1 and RM3 into the high-pressure refrigerant RH. The low-stage compression chamber of thescroll compressor 2 receives circulating refrigerant amount GL in a liquid state separated by the gas-liquid separator 6. The high-stage compression chamber of thescroll compressor 2 receives circulating refrigerant amount GH the amount of which is the sum of circulating refrigerant amount GM in a gaseous state separated by the gas-liquid separator 6 and the circulating refrigerant amount GL introduced from the low-stage compression chamber. The amount of circulating refrigerant introduced to the high-stage compression chamber is therefore larger than that introduced to the low-stage compression chamber. -
FIG. 3 is a sectional view that illustrates the configuration of thescroll compressor 2.FIG. 4 is a sectional view along A-A line ofFIG. 3 .FIG. 5 is a sectional view of a fixedscroll 11 and anorbiting scroll 12 illustrated inFIG. 3 .FIG. 6 is a perspective view of the fixedscroll 11 ofFIG. 4 viewed from diagonally below.FIG. 7 is a perspective view of the orbitingscroll 12 ofFIG. 4 viewed from diagonally above. - The fixed
scroll 11 and the orbitingscroll 12 form a later-describedouter compression area 40, functioning as a low-pressure compression chamber, and a later-describedinner compression area 41, functioning as a high-pressure compression chamber, and conduct two-stage compression. As illustrated inFIG. 3 , the fixedscroll 11 and the orbitingscroll 12 are arranged in ahousing 10 includinghousings scroll 12 making orbital motion with respect to the fixedscroll 11 in a rotational direction AL. Acrankshaft 13 transfers torque from a rotary drive source (not illustrated) to theorbiting scroll 12. Athrust bearing 14 supports rotation of the orbitingscroll 12 in the thrust direction. A medium-pressure chamber 16 and a high-pressure chamber 17 are formed in thehousing 10. Thecrankshaft 13 is provided with abalance weight 15 for balancing orbital motion of the orbitingscroll 12. - A low-pressure refrigerant suction tube L1 is a tube to introduce the low-pressure refrigerant RL into the
outer compression area 40. A medium-pressure refrigerant suction tube L2 is a tube to introduce the medium-pressure refrigerant RM1 into the medium-pressure chamber 16. A high-pressure refrigerant discharge tube L3 is a tube to discharge the high-pressure refrigerant RH, discharged from theinner compression area 41 through adischarge valve 18 and the high-pressure chamber 17, outside thehousing 10. - As illustrated in
FIG. 4 to FIG. 7 , the fixedscroll 11 includes fixed scroll plate-like spiral tooth 11b vertically arranged on abase plate 11a. The orbitingscroll 12 includes orbiting scroll plate-like spiral tooth 12b vertically arranged on abase plate 12a. The fixed scroll plate-like spiral tooth 11b of the fixedscroll 11 and the orbiting scroll plate-like spiral tooth 12b of the orbitingscroll 12 mesh with each other at respective front ends. This structure forms theouter compression area 40 and theinner compression area 41. In theouter compression area 40 and theinner compression area 41, compression chambers are formed outside and inside the orbitingscroll 12. With orbital motion of the orbitingscroll 12, the capacity of the compression chamber is reduced, and the compression chamber is shifted toward the center. This process compresses refrigerant in the compression chamber. - As illustrated in
FIG. 4 , apartition wall 20 is provided that connects the adjacent fixed scroll plate-like spiral tooth 11b so as to partition the compression chamber between a spiral start point PA in the center side of the fixed scroll plate-like spiral tooth 11b, and a spiral end point PB close to the outside. The orbiting scroll plate-like spiral tooth 12b has a separation area E (seeFIG. 7 ) formed therein that splits the orbiting scroll plate-like spiral tooth 12b so as not to interfere with thepartition wall 20 in accordance with orbital motion of the orbitingscroll 12 at a location corresponding to thepartition wall 20. Thepartition wall 20 defines theouter compression area 40 and theinner compression area 41. As illustrated inFIG. 5 to FIG. 7 , providing the separation area E allows the orbiting scroll plate-like spiral tooth 12b to have an orbiting scroll plate-like spiral tooth 32 that orbits in theouter compression area 40 and an orbiting scroll plate-like spiral tooth 33 that orbits in theinner compression area 41. Thepartition wall 20 allows the fixed scroll plate-like spiral tooth 11b to have a fixed scroll plate-like spiral tooth 30 that forms theouter compression area 40 and a fixed scroll plate-like spiral tooth 31 that forms theinner compression area 41. - At an outer end of the spiral of the orbiting scroll plate-
like spiral tooth 32 in theouter compression area 40, a low-pressurerefrigerant suction port 21 is formed and is connected with the low-pressure refrigerant suction tube L1. Furthermore, at the inner end of the spiral of the orbiting scroll plate-like spiral tooth 32 in theouter compression area 40, a medium-pressurerefrigerant discharge port 23 is formed that discharges the medium-pressure refrigerant RM3 compressed in theouter compression area 40 to the medium-pressure chamber 16. At the outer end of the spiral of the orbiting scroll plate-like spiral tooth 33 in theinner compression area 41, a medium-pressurerefrigerant suction port 22 is formed so as to be connected to the medium-pressure chamber 16 to suck the medium-pressure refrigerants RM1 and RM3. Furthermore, at an inner end, which is the center, of the spiral of the orbiting scroll plate-like spiral tooth 33 in theinner compression area 41, a high-pressurerefrigerant discharge port 24 is formed. The high-pressurerefrigerant discharge port 24 is connected to the high-pressure chamber 17 through thedischarge valve 18, and discharges the high-pressure refrigerant RH compressed in theinner compression area 41 outside through the high-pressure refrigerant discharge tube L3. - Because the amount of circulating refrigerant sucked into the
inner compression area 41 is larger than that sucked into theouter compression area 40, as illustrated inFIG. 5 , heights h2 of the fixed scroll plate-like spiral tooth 31 and the orbiting scroll plate-like spiral tooth 33 of theinner compression area 41 are set larger than heights h1 of the fixed scroll plate-like spiral tooth 30 and the orbiting scroll plate-like spiral tooth 32 of theouter compression area 40. By adjusting the heights h1 and h2, the compression capacity of theinner compression area 41 can be larger than that of theouter compression area 40. With this configuration, even when medium-pressure refrigerant expanded by the high-stage expansion valve is introduced to the high-stage compression mechanism, and the amount of circulating refrigerant in the high-stage compression mechanism is increased relative to the amount of circulating refrigerant introduced in the low-stage compression mechanism, it is possible to achieve compactness of the system with a simple configuration. - As illustrated in
FIG. 5 , tip seals 51 and 52 are attached to the respective front ends of the fixed scroll plate-like spiral tooth 11b and the orbiting scroll plate-like spiral tooth 12b. The tip seals 51 and 52 prevent the refrigerant from leaking between the outside and the inside of the fixed scroll plate-like spiral tooth 11b and from leaking between the outside and the inside of the orbiting scroll plate-like spiral tooth 12b during compression by the above-describedouter compression area 40 andinner compression area 41. - Second example not falling under the scope of the claims.
- As illustrated in
FIG. 8 , thescroll compressor 2 of a second example has a spiral end point PB10 of the fixedscroll 11 and a spiral end point PB11 of the orbitingscroll 12 symmetrically arranged with respect to the center (the location of the high-pressure refrigerant discharge port 24). - As illustrated in
FIG. 8(a) , in theouter compression area 40, first the low-pressure refrigerant RL forms a first inner compression chamber 60-1 inside the orbitingscroll 12 and a first outer compression chamber 61-1 outside the orbitingscroll 12. Meanwhile, a full turn (360°) of the orbitingscroll 12 changes the first inner compression chamber 60-1 into a compressed second inner compression chamber 60-2 and changes the first outer compression chamber 61-1 into a compressed second outer compression chamber 61-2. The first inner compression chamber 60-1 and the first outer compression chamber 61-1 have respective statuses of chambers before the full turn of the second inner compression chamber 60-2 and second outer compression chamber 61-2. -
FIG. 8(b) illustrates a state in which theorbiting scroll 12 ofFIG. 8(a) has turned by a communication angle θA at which the second inner compression chamber 60-2 communicates with the medium-pressurerefrigerant discharge port 23. In this state, the medium-pressure refrigerant in the second inner compression chamber 60-2 communicates with the medium-pressurerefrigerant discharge port 23 and is discharged therefrom, and at the same time, communicates with the first outer compression chamber 61-1. Thus, as indicated by an arrow A1, the compressed medium-pressure refrigerant in the second inner compression chamber 60-2, the pressure of which is relatively higher than that of the first outer compression chamber 61-1, leaks into the first outer compression chamber 61-1. This leakage causes loss of recompression and thus reduces the efficiency of compression. - For the above issue, as illustrated in
FIG. 9 , it is preferable that a spiral end point PB20 of the fixedscroll 11 and a spiral end point PB21 of the orbitingscroll 12 be asymmetrically arranged with respect to the center (the location of the high-pressure refrigerant discharge port 24). This asymmetric-type scroll compressor, as illustrated inFIG. 9 , has a spiral end point of the fixedscroll 11 moved by an involute roll angle θa in the range of 0° < θa ≤ 180° from the spiral end point PB10 of the fixedscroll 11 of the symmetric-type scroll compressor. InFIG. 9 , the spiral end point PB20 is such that the involute roll angle θa is 180°. - The inner walls and the outer walls of the fixed
scroll 11 and the orbitingscroll 12 form involute curves LI. The involute curve LI is a plane curve the normal of which is constantly in contact with a specific circle (a basic circle C). As illustrated inFIG. 10 , a position on the involute curve PB(θ) = {PBx(θ), PBy(θ)} is given by the following formula, where θ(°) is the involute roll angle of the involute curve LI and R is the radius of the basic circle C. - In comparison with the symmetric-type scroll compressor of
FIG. 8(a) , the asymmetric-type scroll compressor ofFIG. 9 has the spiral end point PB20 of the fixedscroll 11 and the spiral end point PB21 of the orbitingscroll 12 located at the same angular position. In this layout of the asymmetric-type scroll compressor, when the first inner compression chamber 60-1 and the first outer compression chamber 61-1 ofFIG. 8(a) are formed, an outer compression chamber 61-0 that is half turn behind has already been formed. The outer compression chamber 61-0 changes into the first outer compression chamber 61-1 after a full turn. In other words, when the first inner compression chamber 60-1 is formed, the first outer compression chamber 61-1 has been compressed since a half cycle before. At the communication angle θA inFIG. 8(b) , the pressure of the first outer compression chamber 61-1 becomes substantially equal to the pressure of the second inner compression chamber 60-2. This reduces the amount of the medium-pressure refrigerant compressed in the second inner compression chamber 60-2 to be leaked into the first outer compression chamber 61-1. Accordingly, the loss of recompression decreases and a reduction in the efficiency of compression can be prevented. -
FIGS. 11 are diagrams for comparison between the symmetric-type scroll compressor ofFIG. 8 and the asymmetric-type scroll compressor ofFIG. 9 regarding changes in the pressure of the inner compression chamber and the outer compression chamber and a difference in the pressure therebetween at the communication angle θA. The characteristic curves L60-1, L60-2, L61-0, L61-1, and L61-2 indicate changes in the pressure of the first inner compression chamber 60-1, the second inner compression chamber 60-2, the outer compression chamber 61-0, the first outer compression chamber 61-1, and the second outer compression chamber 61-2, respectively. In the asymmetric-type scroll compressor illustrated inFIG. 11(b) , compression in the outer compression chamber 61-0, which turns into the first outer compression chamber 61-1, starts at an angle of rotation θ1 one turn behind at which the angle of rotation is 0°. This cycle therefore raises the initial pressure (at an angle of rotation of 0°) of the first outer compression chamber 61-1. A pressure difference PR2 at the communication angle θA is therefore reduced in comparison with a pressure difference PR1 of the symmetric-type scroll compressor ofFIG. 11(a) by a pressure difference ΔPR. - As a result of this, as illustrated in
FIG. 12 , the asymmetric-type scroll compressor has a recompression loss S2 that is smaller than a recompression loss S1 of the symmetric-type scroll compressor. - The configuration of the asymmetric-type scroll compressor is applicable to the two-stage compression two-stage expansion cycle of the first example and to a two-stage compression single-stage expansion cycle. Specifically, it is not necessary to employ a configuration in which the heights h2 of the fixed scroll plate-
like spiral tooth 31 and the orbiting scroll plate-like spiral tooth 33 forming theinner compression area 41 is larger than the heights h1 of the fixed scroll plate-like spiral tooth 30 and the orbiting scroll plate-like spiral tooth 32 forming theouter compression area 40. - Third example not falling under the scope of the claims.
- In the
housing 10, the medium-pressure chamber 16 has medium pressure PM. When the pressure of thehousing 10 is the medium pressure PM, the medium pressure PM is applied to the back surface of the orbitingscroll 12, which reduces the thrust load of the orbitingscroll 12. Reducing the mechanical loss and protecting the thrust bearing 14 from wearing can therefore enhance reliability of thescroll compressor 2. - As illustrated in
FIG. 13 , however, the orbiting scroll plate-like spiral tooth 12b of the orbitingscroll 12 receives load in a radial direction A2. The load may cause theorbiting scroll 12 to oscillate when orbiting at a small slant angle. In this state, a gap d is formed between the front end surface, closer to theorbiting scroll 12, of the outer peripheral portion of the fixedscroll 11 and the upper surface of thebase plate 12a of the orbitingscroll 12. The gap d permits the medium-pressure refrigerant RM in the medium-pressure chamber 16 to leak into theouter compression area 40 where the low-pressure refrigerant RL is compressed. Leakage of the medium-pressure refrigerant RM into theouter compression area 40 reduces the efficiency of compression in theouter compression area 40. - The compression efficiency in the
outer compression area 40 is reduced, as illustrated inFIG. 14 , with an increase in the amount of the medium-pressure refrigerant RM in theouter compression area 40. The increase raises the pressure of theouter compression area 40, and power necessary for compression is increased by a region E10. Furthermore, as illustrated inFIG. 15 , when the medium-pressure refrigerant, the temperature of which is higher than that of the low-pressure refrigerant in theouter compression area 40, leaks into theouter compression area 40, the low-pressure refrigerant is heated as indicated by an arrow A10. The temperature of the medium-pressure refrigerant compressed in theouter compression area 40 is accordingly increased relative to the temperature of ideal medium-pressure refrigerant, as indicated by an arrow A11. The high-temperature medium-pressure refrigerant introduced into theinner compression area 41 reduces the density of the medium-pressure refrigerant in theinner compression area 41, which reduces the volumetric efficiency of theinner compression area 41. - In a third example not falling under the scope of the claims, as illustrated in
FIG. 13 , the fixedscroll 11 has anouter wall 11c formed such that the sectional surface of the orbitingscroll 12 in the axial direction is in a U shape. An annular seal is disposed on a sliding surface between the front end surface of theouter wall 11c and thebase plate 12a of the orbitingscroll 12. InFIG. 16 and FIG. 17 , anannular seal 70 is mounted on the front end surface of theouter wall 11c. - The
annular seal 70 may be mounted on thebase plate 12a of the orbitingscroll 12, as illustrated inFIG. 18 . Without being limited to a circular shape, theannular seal 70 may be oval, polygonal, or the like depending on the purpose. - The
annular seal 70 is made of resin, metal, or other materials. Theannular seal 70 is subjected to thermal expansion with an increase in the temperature occurring upon operation of thescroll compressor 2. In particular, theannular seal 70 has a long circumferential length relative to the width and the thickness, and when being subjected to thermal expansion, theannular seal 70 is stretched in the circumferential direction to be constrained by the channel, causes thermal stress to occur, and also generates scuffing due to deformation in the axial direction, and thus may be broken. - The
annular seal 70 therefore preferably has a thermal expansion absorbing portion for absorbing thermal expansion on the occasion of thermal expansion. For example, as illustrated inFIG. 19 , aseparation gap 71 functioning as a clearance during thermal expansion is provided on a part of theannular seal 70. Theseparation gap 71 ofFIG. 19 is slanted with respect to the axial direction of the orbitingscroll 12. A width d10 of theseparation gap 71 in the circumferential direction is determined based on the amount of thermal expansion when thermal expansion occurs. Since theseparation gap 71 is constrained by the channel, a plurality of theseparation gaps 71 are preferably formed in the circumferential direction. Providing theseparation gap 71 can prevent scuffing during thermal expansion and can certainly block leakage of refrigerant. - As illustrated in
FIG. 20 , theseparation gap 71 may be replaced by aseparation gap 72. Theseparation gap 72 is slanted with respect to the circumferential direction of the orbitingscroll 12 or the fixedscroll 11. A width d20 of theseparation gap 72 in the circumferential direction is determined based on the amount of thermal expansion during thermal expansion. Since theseparation gap 72 is constrained by the channel, a plurality of theseparation gaps 72 are preferably formed in the circumferential direction. Formation of theseparation gap 72 can prevent scuffing during thermal expansion and can certainly block leakage of refrigerant. - As illustrated in
FIG. 21 , theseparation gaps hollow portions 73 formed in the area between, but not including, an outerperipheral surface 70a and an innerperipheral surface 70b of theannular seal 70. During thermal expansion, thehollow portion 73 breaks to absorb the thermal expansion, thereby reducing deformation of the outer shape of theannular seal 70. Thehollow portion 73 can more certainly block leakage of refrigerant than an annular seal having a separation gap can. - The third example is applicable to the two-stage compression scroll compressor of the above-described first example and, other than this, applicable to a common scroll compressor. For example, the third example is applicable to a single-stage compression scroll compressor.
- The above first to third examples describe the thermal cycle system illustrated in
FIG. 1 and FIG. 2 as an example thermal cycle system using a two-stage compression two-stage expansion cycle. Thescroll compressor 2 of the first to the third examples is applicable to thermal cycle systems other than the thermal cycle system ofFIG. 1 and FIG. 2 . - For example, as illustrated in
FIG. 22 and FIG. 23 , thesupercooling device 4 may be removed from thethermal cycle system 1 ofFIG. 1 . - As illustrated in
FIG. 24 and FIG. 25 , aninternal heat exchanger 9 may be provided to the thermal cycle system ofFIG. 22 and FIG. 23 . Theinternal heat exchanger 9 transfers heat between the medium-pressure refrigerant RM2 separated by the gas-liquid separator 6 and the low-pressure refrigerant RL ejected from theevaporator 8. - As illustrated in
FIG. 26 and FIG. 27 , the thermal cycle system ofFIG. 1 and FIG. 2 may include aninternal heat exchanger 9a for transferring heat between the high-pressure refrigerant RH right before introduction to the high-stage expansion valve 5 and the low-pressure refrigerant RL ejected from theevaporator 8. - As illustrated in
FIG. 28 and FIG. 29 , the gas-liquid separator 6 included in thethermal cycle system 1 ofFIG. 1 is removed, the high-pressure refrigerant RH ejected from thesupercooling device 4 is branched at a separation point PS, one part of the branched high-pressure refrigerant RH is introduced into anintermediate expansion valve 5a, so as to be depressurized and expanded, and aninternal heat exchanger 9b is provided that performs heat exchange between the depressurized and expanded medium-pressure refrigerant and the other part of the separated high-pressure refrigerant that is not depressurized and expanded. Theinternal heat exchanger 9b uses heat of the other part of the high-pressure refrigerant that is not depressurized and expanded to heat the depressurized and expanded medium-pressure refrigerant. The heated medium-pressure refrigerant is then directly introduced to the high-stage compression chamber of thescroll compressor 2. Meanwhile, the high-pressure refrigerant that is not depressurized and expanded passing theinternal heat exchanger 9b is introduced into the low-stage expansion valve 7 and turns into medium-pressure refrigerant by being depressurized and expanded. - An embodiment of the invention will now be described.
FIG. 30 is a vertical sectional view of ascroll compressor 102 according to the inventionFIG. 31 is a perspective view of thescroll compressor 102 ofFIG. 30 viewed diagonally from the right.FIG. 32 is a perspective view of thescroll compressor 102 ofFIG. 30 viewed diagonally from the left.FIG. 33 is a perspective view of arefrigerant connection cover 100 ofFIG. 30 viewed from the back (in the Y direction) thereof.FIG. 34 is a front view with therefrigerant connection cover 100 mounted.FIG. 35 is a front view with therefrigerant connection cover 100 removed. - In the first to the third examples, a
housing 10a including the medium-pressure chamber 16 and the high-pressure chamber 17 covers the back surface, facing outside, of the fixedscroll 11. Thehousing 10a is connected to thehousing 10b. As illustrated inFIG. 30 to FIG. 35 , in the embodiment, therefrigerant connection cover 100 including a medium-pressurerefrigerant chamber 116 and a high-pressurerefrigerant chamber 117 is directly mounted on the back surface facing the outside (in the Y direction) of the fixedscroll 11. The medium-pressurerefrigerant chamber 116 sucks the medium-pressure refrigerants RM1 and RM3 and discharges a medium-pressure refrigerant RM4 into which the medium-pressure refrigerants RM1 and RM3 have been merged. The high-pressurerefrigerant chamber 117 sucks and discharges the high-pressure refrigerant RH. The medium-pressurerefrigerant chamber 116 and the high-pressurerefrigerant chamber 117 that are formed between therefrigerant connection cover 100 and the fixedscroll 11 are each sealed with O-rings or similar members. Athrust bearing mechanism 114 includes a thrust bearing mechanism and a rotation control mechanism to control rotation of the orbitingscroll 12. More specifically, three units of thethrust bearing mechanisms 114 are disposed on the XZ plane. Therefrigerant connection cover 100 is detachably mounted on thehousing 10. - When the
refrigerant connection cover 100 is directly mounted on the fixedscroll 11, therefrigerant connection cover 100 can be removed independently from the housing 10 (ahousing 10c) includinghousings housing 10. This structure is therefore beneficial in maintainability and compactness. As illustrated inFIG. 30 , thehousing 10c is fixed to the fixedscroll 11, and the fixedscroll 11 constitutes a part of thehousing 10. Because therefrigerant connection cover 100 has no necessity of functioning as a housing, a number of valves, openings, and tubes necessary for two-stage compression, can be arranged in an integrated manner. - The medium-pressure
refrigerant chamber 116 includes arecess portion 105 of the fixedscroll 11 and arecess portion 106 of therefrigerant connection cover 100 that are facing each other. Likewise, the high-pressurerefrigerant chamber 117 includes arecess portion 107 of the fixedscroll 11 and arecess portion 108 of therefrigerant connection cover 100 that are facing each other. The medium-pressurerefrigerant chamber 116 and the high-pressurerefrigerant chamber 117 are partitioned from each other by apartition wall 101. - The
recess portion 105 has a medium-pressurerefrigerant discharge port 123 corresponding to the medium-pressurerefrigerant discharge port 23 communicating with theouter compression area 40, a medium-pressurerefrigerant suction port 122 corresponding to the medium-pressurerefrigerant suction port 22 communicating with theinner compression area 41, and anoutlet opening 151 of a medium-pressure relief hole 141 communicating with theouter compression area 40. Therecess portion 106 has an external medium-pressure refrigerantconnection induction port 126 to suck gaseous medium-pressure refrigerant RM1 introduced from the external gas-liquid separator 6. - As illustrated in
FIG. 30 to FIG. 32 , the medium-pressure refrigerant RM1 is introduced into thehousing 10d through an external medium-pressurerefrigerant suction port 130 along with oil, and reaches a housing medium-pressurerefrigerant suction port 131 through a seal in thehousing 10. The housing medium-pressurerefrigerant suction port 131 and the external medium-pressure refrigerantconnection induction port 126 are connected with each other through an intermediate tube LM. The medium-pressure refrigerant RM1 sucked through the housing medium-pressurerefrigerant suction port 131 is introduced to the medium-pressurerefrigerant chamber 116 through the external medium-pressure refrigerantconnection induction port 126. The intermediate tube LM (seeFIG. 1 ) is a tube to introduce gaseous medium-pressure refrigerant RM1 separated by the gas-liquid separator 6 into the medium-pressurerefrigerant chamber 116. The intermediate tube LM passes thehousing 10 in the middle thereof. - The medium-pressure refrigerant RM1 introduced in the medium-pressure
refrigerant chamber 116 and the medium-pressure refrigerant RM3 discharged through the medium-pressurerefrigerant discharge port 123 merge with each other in the medium-pressurerefrigerant chamber 116, and are discharged to theinner compression area 41 through the medium-pressurerefrigerant suction port 122 as the medium-pressure refrigerant RM4. - The fixed
scroll 11 has a low-pressurerefrigerant suction port 121 corresponding to the low-pressurerefrigerant suction port 21. The low-pressure refrigerant RL is sucked into theouter compression area 40 through the low-pressurerefrigerant suction port 121. - The
recess portion 107 has a high-pressurerefrigerant discharge port 124 corresponding to the high-pressurerefrigerant discharge port 24 and anoutlet opening 152 of a high-pressure relief hole 142 communicating with theouter compression area 40. Therecess portion 108 has a high-pressurerefrigerant ejection port 125 to discharge the high-pressure refrigerant RH in the high-pressurerefrigerant chamber 117 outside. - The
recess portion 105 of the medium-pressurerefrigerant chamber 116 is provided with a check valve V1 for preventing the medium-pressure refrigerant RM3 from circulating back into theouter compression area 40 through the medium-pressurerefrigerant discharge port 123. Therecess portion 107 of the high-pressurerefrigerant chamber 117 is provided with a check valve V2 for preventing the high-pressure refrigerant RH from circulating back into theinner compression area 41 through the high-pressurerefrigerant discharge port 124. - The
recess portion 105 of the medium-pressurerefrigerant chamber 116 is provided with a medium-pressure relief valve V11 serving as a medium-pressure relief unit, at the outlet opening 151 of the medium-pressure relief hole 141 (seeFIG. 6 andFIG. 35 ) to control the pressure of refrigerant in theouter compression area 40 under a first predetermined pressure. Therecess portion 107 of the high-pressurerefrigerant chamber 117 is provided with a high-pressure relief valve V12, serving as a high-pressure relief unit, at the outlet opening 152 of a high-pressure relief hole 142 (seeFIG. 6 andFIG. 35 ) to control the pressure of refrigerant in theinner compression area 41 under a second predetermined pressure. - The medium-pressure
refrigerant discharge port 123, the medium-pressurerefrigerant suction port 122, and the high-pressurerefrigerant discharge port 124 are arranged on thehousing 10. Therefrigerant connection cover 100 including an external medium-pressure refrigerantconnection induction port 126 and a high-pressurerefrigerant ejection port 125 is mounted on thehousing 10, whereby the medium-pressurerefrigerant chamber 116 and the high-pressurerefrigerant chamber 117 are formed. - The medium-pressure
refrigerant suction port 122, the medium-pressurerefrigerant discharge port 123, and the external medium-pressure refrigerantconnection induction port 126 communicate with the medium-pressurerefrigerant chamber 116. The high-pressurerefrigerant discharge port 124 and the high-pressurerefrigerant ejection port 125 communicate with a high-pressurerefrigerant chamber 117. The medium-pressurerefrigerant suction port 122 and the high-pressurerefrigerant discharge port 124 are open in the same direction as the medium-pressurerefrigerant discharge port 123. The housing medium-pressurerefrigerant suction port 131 and the medium-pressurerefrigerant discharge port 123 are open in the same direction to discharge medium-pressure refrigerant through a seal in thehousing 10. - The above medium-pressure relief valve V11, the high-pressure relief valve V12, the check valve V1, and the check valve V2 are exposed on the surface of the
housing 10 when therefrigerant connection cover 100 is removed, whereby maintainability is enhanced. - The medium-pressure
refrigerant chamber 116 has a larger capacity than that of the high-pressurerefrigerant chamber 117. The medium-pressure refrigerants RM1, RM3, and RM4 have smaller density than that of the high-pressure refrigerant RH and easily cause pressure loss. The medium-pressurerefrigerant chamber 116 is increased in a capacity to reduce the pressure loss. - In
FIG. 30 to FIG. 35 , the medium-pressurerefrigerant chamber 116 has an increased capacity by making the cross-sectional area of the medium-pressurerefrigerant chamber 116 larger than that of the high-pressurerefrigerant chamber 117 with a depth d1 of the medium-pressurerefrigerant chamber 116 being the same as a depth d2 of the high-pressurerefrigerant chamber 117. Without being limited thereto, the medium-pressurerefrigerant chamber 116 may have an increased capacity by making the depth d1 of the medium-pressurerefrigerant chamber 116 larger than the depth d2 of the high-pressurerefrigerant chamber 117. The pressure of the medium-pressure refrigerant is smaller than that of the high-pressure refrigerant, and therefrigerant connection cover 100 is allowed to reduce the thickness of a portion around the medium-pressurerefrigerant chamber 116, which makes it easy to increase the depth d2. - When the capacity of the medium-pressure
refrigerant chamber 116 or the high-pressurerefrigerant chamber 117 is to be changed, the capacity (the depth) of therecess portion 106 or therecess portion 108 formed on therefrigerant connection cover 100 is controlled. The capacity of the medium-pressurerefrigerant chamber 116 or the high-pressurerefrigerant chamber 117 can be thus changed without changing the structure of thehousing 10 side. -
Notches 140 formed in therefrigerant connection cover 100 are used for positioning therefrigerant connection cover 100 to be mounted. - The thermal cycle system is a heat pump system in the case of heating using the above-described
condenser 3 and the thermal cycle system is an ordinary freezing system in the case of cooling using theevaporator 8. - Although the above-described
scroll compressor 2 is a two-stage compressor including theouter compression area 40 and theinner compression area 41, it is not limited thereto, and thescroll compressor 2 may be a multi-stage compressor. -
- 1 THERMAL CYCLE SYSTEM
- 2, 102 SCROLL COMPRESSOR
- 3 CONDENSER
- 4 SUPERCOOLING DEVICE
- 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, 10b, 10c, 10d HOUSING
- 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 MEDIUM-PRESSURE CHAMBER
- 17 HIGH-PRESSURE CHAMBER
- 18 DISCHARGE VALVE
- 20 PARTITION WALL
- 21, 121 LOW-PRESSURE REFRIGERANT SUCTION PORT
- 22, 122 MEDIUM-PRESSURE REFRIGERANT SUCTION PORT (MEDIUM-PRESSURE REFRIGERANT EJECTION PORT)
- 23, 123 MEDIUM-PRESSURE REFRIGERANT DISCHARGE PORT (MEDIUM-PRESSURE REFRIGERANT INDUCTION PORT)
- 24, 124 HIGH-PRESSURE REFRIGERANT DISCHARGE PORT (HIGH-PRESSURE REFRIGERANT INDUCTION PORT)
- 30, 31 FIXED SCROLL PLATE-LIKE SPIRAL TOOTH
- 32, 33 ORBITING SCROLL PLATE-LIKE SPIRAL TOOTH
- 40 OUTER COMPRESSION AREA
- 41 INNER COMPRESSION AREA
- 51, 52 TIP SEAL
- 60-1 FIRST INNER COMPRESSION CHAMBER
- 60-2 SECOND INNER COMPRESSION CHAMBER
- 61-0 OUTER COMPRESSION CHAMBER
- 61-1 FIRST OUTER COMPRESSION CHAMBER
- 61-2 SECOND OUTER COMPRESSION CHAMBER
- 70 ANNULAR SEAL
- 70a OUTER PERIPHERAL SURFACE
- 70b INNER PERIPHERAL SURFACE
- 71, 72 SEPARATION GAP
- 73 HOLLOW PORTION
- 100 REFRIGERANT CONNECTION COVER
- 101 PARTITION WALL
- 105 to 108 RECESS PORTION
- 116 MEDIUM-PRESSURE REFRIGERANT CHAMBER
- 117 HIGH-PRESSURE REFRIGERANT CHAMBER
- 114 THRUST BEARING MECHANISM
- 125 HIGH-PRESSURE REFRIGERANT EJECTION PORT
- 126 EXTERNAL MEDIUM-PRESSURE REFRIGERANT CONNECTION INDUCTION PORT
- 130 EXTERNAL MEDIUM-PRESSURE REFRIGERANT SUCTION PORT
- 131 HOUSING MEDIUM-PRESSURE REFRIGERANT SUCTION PORT
- 141 MEDIUM-PRESSURE RELIEF HOLE
- 142 HIGH-PRESSURE RELIEF HOLE
- 151, 152 OUTLET OPENING
- AL ROTATIONAL DIRECTION
- d GAP
- E SEPARATION AREA
- GH, GL, GM CIRCULATING REFRIGERANT AMOUNT
- L1 LOW-PRESSURE REFRIGERANT SUCTION TUBE
- L2 MEDIUM-PRESSURE REFRIGERANT SUCTION TUBE
- L3 HIGH-PRESSURE REFRIGERANT DISCHARGE TUBE
- LM INTERMEDIATE TUBE
- V1, V2 CHECK VALVE
- V11 MEDIUM-PRESSURE RELIEF VALVE (MEDIUM-PRESSURE RELIEF UNIT)
- V12 HIGH-PRESSURE RELIEF VALVE (HIGH-PRESSURE RELIEF UNIT)
- θA COMMUNICATION ANGLE
Claims (11)
- A multi-stage compressor (2,102), comprising:a plurality of compression chambers (40,41) formed in a housing (10);a medium-pressure refrigerant discharge port (23,123) that discharges medium-pressure refrigerant from a low-stage compression chamber (40) of the compression chambers (40,41);a medium-pressure refrigerant suction port (22,122) that is open in a same direction as the medium-pressure refrigerant discharge port (23,123) and induces the medium-pressure refrigerant into a high-stage compression chamber (41) of the compression chambers (40,41);a high-pressure refrigerant discharge port (24,124) that is open in a same direction as the medium-pressure refrigerant discharge port (23,123) and discharges high-pressure refrigerant discharged from the high-stage compression chamber (41) of the compression chambers (40,41); anda refrigerant connection cover (100) that is detachably mounted on the housing (10),wherein the refrigerant connection cover (100) forms a medium-pressure refrigerant chamber (116), which communicates with the medium-pressure refrigerant suction port (22,122) and the medium-pressure refrigerant discharge port (23,123) and which has an external medium-pressure refrigerant connection induction port (126) that is open toward an outside, wherein the refrigerant connection cover (100) forms a high-pressure refrigerant chamber (117), which communicates with the high-pressure refrigerant discharge port (24,124) and which has a high-pressure refrigerant ejection port (125) open toward an outside,wherein the multi-stage compressor (2,102) is a scroll compressor including an orbiting scroll (12) and a fixed scroll (11), and the fixed scroll (11) constitutes a part of the housing (10), and the refrigerant connection cover (100) is mounted on the fixed scroll (11),wherein the medium-pressure refrigerant chamber (116) includes a recess portion (105) of the fixed scroll (11) and a recess portion (106) of the refrigerant connection cover (100) that are facing each other,wherein the high-pressure refrigerant chamber (117) includes a recess portion (107) of the fixed scroll (11) and a recess portion (108) of the refrigerant connection cover (100) that are facing each other.
- The multi-stage compressor (2,102) according to claim 1, whereinthe housing (10) has a housing medium-pressure refrigerant suction port (131) that is open in a same direction as the medium-pressure refrigerant discharge port (23,123) and that discharges medium-pressure refrigerant through a seal (51,52,70) in the housing (10), andthe housing medium-pressure refrigerant suction port (131) and the external medium-pressure refrigerant connection induction port (126) are connected with each other with a tube (LM).
- The multi-stage compressor (2,102) according to claim 1, wherein a high-pressure relief unit (V12) that allows the high-stage compression chamber (41) and the high-pressure refrigerant chamber (117) to communicate with each other when an inner pressure of the high-stage compression chamber (41) becomes equal to or greater than a predetermined value is provided in the high-pressure refrigerant chamber (117) of the housing (10).
- The multi-stage compressor (2,102) according to claim 1, wherein a medium-pressure relief unit (V11) that allows the low-stage compression chamber (40) and the medium-pressure refrigerant chamber (116) to communicate with each other when an inner pressure of the low-stage compression chamber (40) becomes equal to or greater than a predetermined value is provided in the medium-pressure refrigerant chamber (116) of the housing (10).
- The multi-stage compressor (2,102) according to claim 1, wherein a check valve (V1) for preventing circulating back to the low-stage compression chamber (40) through the medium-pressure refrigerant discharge port (23,123) is provided in the medium-pressure refrigerant chamber (116) of the housing (10).
- The multi-stage compressor (2,102) according to claim 1, wherein a check valve (V2) for preventing circulating back to the high-stage compression chamber (41) through the high-pressure refrigerant discharge port (24,124) is provided in the high-pressure refrigerant chamber (117) of the housing (10).
- The multi-stage compressor (2,102) according to claim 1, wherein a capacity of the medium-pressure refrigerant chamber (116) is larger than a capacity of the high-pressure refrigerant chamber (117).
- The multi-stage compressor (2, 102) according to claim 7, wherein a cross-sectional area of the medium-pressure refrigerant chamber (116) is larger than a cross-sectional area of the high-pressure refrigerant chamber (117), with a depth (d1) of the medium-pressure refrigerant chamber (116) being the same as a depth (d2) of the high-pressure refrigerant chamber (117).
- The multi-stage compressor (2, 102) according to claim 7, wherein a depth (d1) of the medium-pressure refrigerant chamber (116) is larger than a depth (d2) of the high-pressure refrigerant chamber (117).
- The multi-stage compressor (2,102) according to claim 1, wherein a notch (140) for positioning is formed on the refrigerant connection cover (100).
- The multi-stage compressor (2,102) according to any one of claims 1 to 10, wherein the multi-stage compressor (2,102) is used for a two-stage compression two-stage expansion thermal cycle system.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2018034517 | 2018-09-18 | ||
PCT/JP2019/035772 WO2020059608A1 (en) | 2018-09-18 | 2019-09-11 | Multiple-stage compressor |
Publications (3)
Publication Number | Publication Date |
---|---|
EP3842640A1 EP3842640A1 (en) | 2021-06-30 |
EP3842640A4 EP3842640A4 (en) | 2021-10-27 |
EP3842640B1 true EP3842640B1 (en) | 2024-03-20 |
Family
ID=69887654
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19863099.8A Active EP3842640B1 (en) | 2018-09-18 | 2019-09-11 | Multi-stage compressor |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP3842640B1 (en) |
JP (1) | JP6943345B2 (en) |
CN (1) | CN111868384B (en) |
WO (1) | WO2020059608A1 (en) |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4911620A (en) * | 1988-05-12 | 1990-03-27 | Tecumseh Products Company | Scroll compressor top cover plate |
JPH06159278A (en) * | 1992-04-01 | 1994-06-07 | Nippon Soken Inc | Rolling piston type compressor |
JP4031223B2 (en) * | 2001-09-27 | 2008-01-09 | アネスト岩田株式会社 | Scroll type fluid machine |
JP2004332556A (en) | 2003-04-30 | 2004-11-25 | Tokico Ltd | Multistage compressor |
JP4699109B2 (en) * | 2005-06-29 | 2011-06-08 | 株式会社ケーヒン | Scroll compressor |
FR2947308B1 (en) * | 2009-06-30 | 2014-04-18 | Danfoss Commercial Compressors | MULTI-STAGE VOLUME MACHINE |
KR101280155B1 (en) * | 2009-11-06 | 2013-06-28 | 미쓰비시덴키 가부시키가이샤 | Heat pump device, two-stage compressor, and method of operating heat pump device |
JP6661916B2 (en) * | 2015-07-31 | 2020-03-11 | 富士電機株式会社 | Scroll compressor and heat cycle system |
JP2018009565A (en) * | 2016-06-30 | 2018-01-18 | 株式会社デンソー | Multi-stage compressor |
JP6926635B2 (en) * | 2016-08-16 | 2021-08-25 | 富士電機株式会社 | Scroll compressor |
JP2018127903A (en) * | 2017-02-06 | 2018-08-16 | 株式会社Soken | Compressor |
CN107044416A (en) * | 2017-03-07 | 2017-08-15 | 无锡五洋川普涡旋科技有限公司 | A kind of water-cooled three stage compression oil-free vortex air compressor |
-
2019
- 2019-09-11 CN CN201980016332.XA patent/CN111868384B/en active Active
- 2019-09-11 JP JP2020548408A patent/JP6943345B2/en active Active
- 2019-09-11 EP EP19863099.8A patent/EP3842640B1/en active Active
- 2019-09-11 WO PCT/JP2019/035772 patent/WO2020059608A1/en unknown
Also Published As
Publication number | Publication date |
---|---|
CN111868384B (en) | 2022-06-03 |
JPWO2020059608A1 (en) | 2021-02-15 |
EP3842640A1 (en) | 2021-06-30 |
CN111868384A (en) | 2020-10-30 |
WO2020059608A1 (en) | 2020-03-26 |
EP3842640A4 (en) | 2021-10-27 |
JP6943345B2 (en) | 2021-09-29 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP2574791B1 (en) | Scroll compressor | |
US8568118B2 (en) | Compressor having piston assembly | |
US7775783B2 (en) | Refrigeration system including a scroll expander | |
US9239053B2 (en) | Hermetically sealed scroll compressor | |
EP1820970A1 (en) | Compressor | |
JP6661916B2 (en) | Scroll compressor and heat cycle system | |
US10563891B2 (en) | Variable displacement scroll compressor | |
JP2007064005A (en) | Scroll compressor and air conditioner | |
KR20060030521A (en) | Scroll-type fluid machine | |
EP3842640B1 (en) | Multi-stage compressor | |
US7556485B2 (en) | Rotary compressor with reduced refrigeration gas leaks during compression while preventing seizure | |
US10190586B2 (en) | Scroll compressor and air conditioner | |
US12012963B2 (en) | Scroll compressor with economizer injection | |
US8118577B2 (en) | Scroll compressor having optimized cylinder oil circulation rate of lubricant | |
WO2016157688A1 (en) | Rotating cylinder type compressor | |
WO2019163628A1 (en) | Scroll fluid machine | |
WO2023182457A1 (en) | Screw compressor and freezer | |
JP2018028313A (en) | Scroll compressor | |
JP5404100B2 (en) | Scroll compressor and air conditioner | |
US12000396B2 (en) | Scroll compressor | |
JP2019085912A (en) | Multistage scroll compressor | |
EP3751142A1 (en) | Compressor and refrigeration cycle device | |
CN118103598A (en) | Scroll compressor having a rotor with a rotor shaft having a rotor shaft with a | |
CN118057029A (en) | Compressor and refrigeration cycle device | |
JP2019090389A (en) | Scroll compressor |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE |
|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
17P | Request for examination filed |
Effective date: 20200901 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
A4 | Supplementary search report drawn up and despatched |
Effective date: 20210924 |
|
RIC1 | Information provided on ipc code assigned before grant |
Ipc: F04C 28/26 20060101ALI20210920BHEP Ipc: F04C 23/00 20060101ALI20210920BHEP Ipc: F04C 18/02 20060101AFI20210920BHEP |
|
DAV | Request for validation of the european patent (deleted) | ||
DAX | Request for extension of the european patent (deleted) | ||
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: GRANT OF PATENT IS INTENDED |
|
INTG | Intention to grant announced |
Effective date: 20231017 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE PATENT HAS BEEN GRANTED |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: EP |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R096 Ref document number: 602019048773 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D |