Patent Grant
11506201
The present disclosure relates to a scroll compressor.
A scroll compressor includes a housing that accommodates a compression mechanism. The compression mechanism includes compression chambers. The compression chambers compress refrigerant that has been drawn into the compression chambers. The compression mechanism discharges the compressed refrigerant. The compression mechanism includes a fixed scroll and a movable scroll. The compression chambers are formed by the fixed scroll and the movable scroll meshing with each other.
Japanese Laid-Open Patent Publication No. 2015-129475 discloses a scroll compressor that includes a housing incorporating a compression mechanism. The housing includes an intermediate pressure chamber. Refrigerant of an intermediate pressure is introduced into the intermediate pressure chamber from the external refrigerant circuit. The intermediate pressure is higher than the suction pressure of the refrigerant drawn into the compression chambers and lower than the discharge pressure of the refrigerant discharged from the compression chambers. The compression mechanism includes two injection ports, which respectively introduce the refrigerant of the intermediate pressure in the intermediate pressure chamber into two of the compression chambers. The housing includes two supply passages, which are connected to the intermediate pressure chamber and supply the refrigerant of the intermediate pressure chamber to the injection ports. The housing further incorporates a check valve. The check valve prevents backflow of the refrigerant from the compression chambers via the supply passages and the injection ports. During a high load operation of the scroll compressor, the check valve opens, so that refrigerant of the intermediate pressure, which is introduced into the intermediate pressure chamber from the external refrigerant circuit, is introduced into two of the compression chambers via the supply passages and the injection ports. This increases the flow rate of the refrigerant introduced to the compression chambers, thereby improving the performance of the motor-driven compressor during a high load operation.
In order to increase the flow rate of the refrigerant of the intermediate pressure introduced into the compression chambers from the injection ports, the diameter of the injection ports may be increased. However, an increase in the diameter of the injection ports may prevent the openings of the injection ports on the side corresponding to the compression chambers from being completely closed by the movable scroll during a compression process of the scroll compressor. This may cause the refrigerant to flow to the intermediate pressure chamber from the compression chambers in a compression process through the injection ports and the supply passages, reducing the compression efficiency. Therefore, the space in the intermediate pressure chamber that is between the check valve and the supply passages may become a dead volume, which is desired to be minimized.
It is an objective of the present disclosure to provide a scroll compressor that limits reduction in compression efficiency.
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
In one general aspect, a scroll compressor includes a compression mechanism and a housing. The compression mechanism that includes a fixed scroll and a movable scroll, and compression chambers, which are formed by meshing of the fixed scroll and the movable scroll. The compression mechanism compresses refrigerant that has been drawn into the compression chambers, and discharges the compressed refrigerant. The housing includes an intermediate pressure chamber. Refrigerant of an intermediate pressure is introduced into the intermediate pressure chamber from an external refrigerant circuit. The intermediate pressure is higher than a suction pressure of the refrigerant drawn into the compression chambers and lower than a discharge pressure of the refrigerant discharged from the compression chambers. The compression mechanism includes two injection ports, which respectively introduce the refrigerant of the intermediate pressure in the intermediate pressure chamber into two of the compression chambers. The housing includes two supply passages and a check valve. The two supply passages are connected to the intermediate pressure chamber and respectively supply the refrigerant of the intermediate pressure to the two injection ports. The check valve prevents backflow of the refrigerant from the compression chambers via the supply passages and the injection ports. A distance between openings of the two supply passages that are closest to the intermediate pressure chamber is less than a distance between openings of the two injection ports that are closest to the compression chambers.
Other features and aspects will be apparent from the following detailed description, the drawings, and the claims.
Throughout the drawings and the detailed description, the same reference numerals refer to the same elements. The drawings may not be to scale, and the relative size, proportions, and depiction of elements in the drawings may be exaggerated for clarity, illustration, and convenience.
This description provides a comprehensive understanding of the methods, apparatuses, and/or systems described. Modifications and equivalents of the methods, apparatuses, and/or systems described are apparent to one of ordinary skill in the art. Sequences of operations are exemplary, and may be changed as apparent to one of ordinary skill in the art, with the exception of operations necessarily occurring in a certain order. Descriptions of functions and constructions that are well known to one of ordinary skill in the art may be omitted.
Exemplary embodiments may have different forms, and are not limited to the examples described. However, the examples described are thorough and complete, and convey the full scope of the disclosure to one of ordinary skill in the art.
A scroll compressor 10 according to an embodiment will now be described with reference to
As shown in
The housing 11 includes a motor housing member 15, a discharge housing member 16, an intermediate housing member 17, and a shaft support housing member 18. The motor housing member 15, the discharge housing member 16, the intermediate housing member 17, and the shaft support housing member 18 are made of metal such as aluminum.
The motor housing member 15 has a bottom wall 15a and a tubular peripheral wall 15b, which extends from the outer circumference of the bottom wall 15a. The motor housing member 15 has a tubular shape with a closed end. An axial direction of the peripheral wall 15b agrees with an axial direction of the rotary shaft 12. The peripheral wall 15b has internal thread holes 15c at the open end. The peripheral wall 15b also has a suction port 15h. The suction port 15h is formed in a part of the peripheral wall 15b that is relatively close to the bottom wall 15a. The suction port 15h connects the inside and the outside of the motor housing member 15 to each other.
The bottom wall 15a has a cylindrical boss 15f protruding from the inner surface. The rotary shaft 12 has a first end inserted into the boss 15f. A bearing 19 is provided between the inner circumferential surface of the boss 15f and the outer circumferential surface of a first end of the rotary shaft 12. The bearing 19 is, for example, a rolling-element bearing. The first end of the rotary shaft 12 is rotationally supported by the motor housing member 15 with the bearing 19.
As shown in
The shaft support housing member 18 has a flange 23 at an end of the peripheral wall 22 of the main body 20 on the side opposite to the bottom wall 21. The flange 23 extends outward in the radial direction of the rotary shaft 12. The flange 23 is annular. The flange 23 has an end face 23a located closest to the bottom wall 21. The end face 23a has a first surface 231a and a second surface 232a, which extend in the radial direction. The first surface 231a and the second surface 232a are annular. The first surface 231a is continuous with the outer circumferential surface of the peripheral wall 22 and extends in the radial direction from the end of the outer circumferential surface of the peripheral wall 22 that is on the side opposite to the bottom wall 21. The second surface 232a is located outward of the first surface 231a in the radial direction. The second surface 232a is farther from the bottom wall 21 than the first surface 231a in the axial direction of the rotary shaft 12. The outer peripheral edge of the first surface 231a on the outer side in the radial direction is connected to the inner peripheral edge of the second surface 232a on the inner side in the radial direction by a step surface 233a, which extends in the axial direction. The step surface 233a is annular.
The second surface 232a faces an open end face 15e of the peripheral wall 15b of the motor housing member 15. The flange 23 has bolt insertion holes 23h in the outer circumference. The bolt insertion holes 23h extend through the flange 23 in the thickness direction. The bolt insertion holes 23h open in the second surface 232a of the flange 23. The bolt insertion holes 23h are connected to the internal thread holes 15c of the motor housing member 15. The motor housing member 15 and the shaft support housing member 18 define a motor chamber 24 formed in the housing 11. Refrigerant is drawn into the motor chamber 24 from an external refrigerant circuit 25 via the suction port 15h. The motor chamber 24 is thus a suction chamber, into which refrigerant is drawn through the suction port 15h.
An end face 12e of the second end of the rotary shaft 12 is located on the inner side of the peripheral wall 22 of the main body 20. A bearing 26 is provided between the inner circumferential surface of the peripheral wall 22 and the outer circumferential surface of the rotary shaft 12. The bearing 26 is, for example, a rolling-element bearing. The rotary shaft 12 is rotationally supported by the shaft support housing member 18 with the bearing 26. The shaft support housing member 18 thus rotationally supports the rotary shaft 12.
As shown in
The intermediate housing member 17 has a bottom wall 17a and a tubular peripheral wall 17b, which extends from the outer circumference of the bottom wall 17a. The axial direction of the peripheral wall 17b agrees with the axial direction of the rotary shaft 12. The peripheral wall 17b has an end face 17e, which faces an end face 23b of the flange 23 on the side opposite to the bottom wall 21. The intermediate housing member 17 has bolt insertion holes 17h in the outer circumference. The bolt insertion holes 17h are connected to the bolt insertion holes 23h of the flange 23. The bolt insertion holes 17h extend through the bottom wall 17a and the peripheral wall 17b.
The discharge housing member 16 is block-shaped. The discharge housing member 16 is attached to the bottom wall 17a of the intermediate housing member 17 with a plate-shaped gasket 29. The discharge housing member 16 is attached to an end face of the bottom wall 17a on the side opposite to the peripheral wall 17b. The gasket 29 serves as a seal between the discharge housing member 16 and the intermediate housing member 17. The gasket 29 has bolt insertion holes 29h in the outer circumference. The bolt insertion holes 29h are connected to the bolt insertion holes 17h of the intermediate housing member 17. The discharge housing member 16 has bolt insertion holes 16h in the outer circumference. The bolt insertion holes 16h are connected to the bolt insertion holes 29h.
Bolts 30, which are passed through the bolt insertion holes 16h, 17h, 29h, are threaded into bolt insertion holes 23h of the flange 23 and the internal thread holes 15c of the motor housing member 15 in that order. This couples the shaft support housing member 18 to the peripheral wall 15b of the motor housing member 15, and couples the intermediate housing member 17 to the flange 23 of the shaft support housing member 18. Further, the discharge housing member 16 is coupled to the intermediate housing member 17 together with the gasket 29. Accordingly, the motor housing member 15, the shaft support housing member 18, the intermediate housing member 17, and the discharge housing member 16 are arranged in that order in the axial direction of the rotary shaft 12.
The flange 23 is held between the peripheral wall 17b of the intermediate housing member 17 and the peripheral wall 15b of the motor housing member 15. The intermediate housing member 17 is arranged between the discharge housing member 16 and the motor housing member 15. The intermediate housing member 17, the shaft support housing member 18, and the motor housing member 15 are integrally fixed by the bolts 30, which extend through the intermediate housing member 17 and the flange 23 and are threaded to the motor housing member 15. A plate-shaped gasket (not shown) is arranged between the outer circumference of the flange 23 and the open end face 15e of the peripheral wall 15b of the motor housing member 15. This gasket serves as a seal between the flange 23 and the peripheral wall 15b of the motor housing member 15. Also, a plate-shaped gasket (not shown) is arranged between the outer circumference of the flange 23 and the open end face 17e of the peripheral wall 17b of the intermediate housing member 17. This gasket serves as a seal between the flange 23 and the peripheral wall 17b of the intermediate housing member 17.
As shown in
The fixed scroll 31 is located between the movable scroll 32 and the bottom wall 17a of the intermediate housing member 17 in the axial direction of the rotary shaft 12. The fixed scroll 31 has a disc-shaped fixed base plate 31a and a fixed volute wall 31b, which extends from the fixed base plate 31a in a direction away from the bottom wall 17a of the intermediate housing member 17. The fixed scroll 31 has a tubular fixed outer peripheral wall 31c, which extends from the outer circumference of the fixed base plate 31a. The fixed outer peripheral wall 31c surrounds the fixed volute wall 31b. The fixed outer peripheral wall 31c has an open end face that is located at a position farther from the fixed base plate 31a than the distal end face of the fixed volute wall 31b.
The movable scroll 32 has a disc-shaped movable base plate 32a, which faces the fixed base plate 31a, and a movable volute wall 32b, which extends from the movable base plate 32a toward the fixed base plate 31a. The fixed volute wall 31b and the movable volute wall 32b mesh with each other. The movable volute wall 32b is located on the inner side of the fixed outer peripheral wall 31c. The distal end face of the fixed volute wall 31b contacts the movable base plate 32a. The distal end face of the movable volute wall 32b contacts the fixed base plate 31a. Compression chambers 33, which compress refrigerant, are defined by the fixed base plate 31a, the fixed volute wall 31b, the fixed outer peripheral wall 31c, the movable base plate 32a, and the movable volute wall 32b. Therefore, the compression mechanism 13 has the compression chambers 33, which are formed by meshing of the fixed scroll 31 and the movable scroll 32, and compress refrigerant that has been drawn into the compression chambers 33. The compression mechanism 13 discharges the compressed refrigerant.
The fixed base plate 31a has a circular discharge port 31h at the central portion. The discharge port 31h extends through the fixed base plate 31a in the thickness direction. A discharge valve mechanism 34, which selectively opens and closes the discharge port 31h, is attached to an end face of fixed base plate 31a that is on the side opposite to the movable scroll 32.
The movable base plate 32a has a boss 32f, which projects from an end face 32e on the side opposite to the fixed base plate 31a. The boss 32f is cylindrical. The axial direction of the boss 32f agrees with the axial direction of the rotary shaft 12. Multiple recesses 35 are formed in the end face 32e around the boss 32f. The recesses 35 are circular holes. The recesses 35 are arranged at predetermined intervals in the circumferential direction of the rotary shaft 12. An annular ring member 36 is fitted in each of the recesses 35. The shaft support housing member 18 has pins 37, which protrude from an end face closest to the intermediate housing member 17. The pins 37 are inserted into the corresponding ring members 36.
The fixed scroll 31 is positioned in relation to the shaft support housing member 18 while being restricted from rotating about the axis L1 of the rotary shaft 12 on the inner side of the peripheral wall 17b of the intermediate housing member 17. The end face of the shaft support housing member 18 that is closest to the intermediate housing member 17 contacts the open end face of the fixed outer peripheral wall 31c. The fixed scroll 31 is held between the bottom wall 17a of the intermediate housing member 17 and the end face of the shaft support housing member 18 that is closest to the intermediate housing member 17. The fixed scroll 31 is thus arranged on the inner side of the peripheral wall 17b of the intermediate housing member 17, while being restricted from moving in the axial direction of the rotary shaft 12 on the inner side of the peripheral wall 17b of the intermediate housing member 17.
The rotary shaft 12 has an eccentric shaft 38, which projects from the end face 12e of the second end and is located at a position eccentric from the axis L1 of the rotary shaft 12. The eccentric shaft 38 protrudes toward the movable scroll 32. The axial direction of the eccentric shaft 38 agrees with the axial direction of the rotary shaft 12. The eccentric shaft 38 is inserted into the boss 32f.
A bushing 40, which is integrated with a balance weight 39, is fitted to the outer circumferential surface of the eccentric shaft 38. The balance weight 39 is integral with the bushing 40. The balance weight 39 is accommodated inside the peripheral wall 22 of the shaft support housing member 18. The movable scroll 32 is supported by the eccentric shaft 38 with the bushing 40 and a rolling-element bearing 40a so as to be rotational relative to the eccentric shaft 38.
Rotation of the rotary shaft 12 is transmitted to the movable scroll 32 via the eccentric shaft 38, the bushing 40, and the rolling-element bearing 40a, so that the movable scroll 32 orbits. At this time, contact between the pins 37 and the inner circumferential surfaces of the respective ring members 36 prevents the movable scroll 32 from rotating and only allows the movable scroll 32 to orbit. This causes the movable scroll 32 to orbit with the movable volute wall 32b contacting the fixed volute wall 31b. Accordingly, the volume of each compression chamber 33 decreases to compress the refrigerant. In this manner, the rotation of the rotary shaft 12 drives the compression mechanism 13. The balance weight 39 cancels out the centrifugal force acting on the movable scroll 32 when the movable scroll 32 orbits, thereby reducing the amount of imbalance of the movable scroll 32.
The motor housing member 15 has a first groove 41 formed in a part of the inner circumferential surface of the peripheral wall 15b. The first groove 41 opens in the open end of the peripheral wall 15b. Also, the flange 23 of the shaft support housing member 18 has a first hole 42 in the outer circumference. The first hole 42 is connected to the first groove 41. The first hole 42 extends through the flange 23 in the thickness direction. Further, the peripheral wall 17b of the intermediate housing member 17 has a second groove 43 in a part of the inner circumferential surface. The second groove 43 is connected to the first hole 42. The fixed outer peripheral wall 31c of the fixed scroll 31 has a second hole 44, which extends through the fixed outer peripheral wall 31c in the thickness direction. The second hole 44 is connected to the second groove 43. The second hole 44 is connected to the outermost part of each compression chamber 33.
The refrigerant in the motor chamber 24 is drawn into the outermost part of each compression chamber 33 through the first groove 41, the first hole 42, the second groove 43, and the second hole 44. The refrigerant that has been drawn into the outermost part of each compression chamber 33 is compressed in the compression chamber 33 by orbiting motion of the movable scroll 32.
The housing 11 has a back pressure chamber 45. The back pressure chamber 45 is arranged on the inner side of the peripheral wall 22 of the shaft support housing member 18. In the housing 11, the back pressure chamber 45 is therefore formed between the inner surface of the shaft support housing member 18 and the surface of the movable base plate 32a on the side opposite to the fixed base plate 31a. The shaft support housing member 18 defines the back pressure chamber 45 and the motor chamber 24.
The movable scroll 32 has a back pressure introducing passage 46. The back pressure introducing passage 46 extends through the movable base plate 32a and the movable volute wall 32b and introduces the refrigerant in the compression chambers 33 to the back pressure chamber 45. Since the refrigerant in the compression chambers 33 is introduced into the back pressure chamber 45 via the back pressure introducing passage 46, the pressure in the back pressure chamber 45 is higher than that of the motor chamber 24. The high pressure in the back pressure chamber 45 urges the movable scroll 32 toward the fixed scroll 31, so that the distal end face of the movable volute wall 32b is pressed against the fixed base plate 31a.
The rotary shaft 12 has an in-shaft passage 47. The in-shaft passage 47 has a first end that opens in the end face 12e of the rotary shaft 12. The in-shaft passage 47 has a second end that is open in a part of the outer circumferential surface of the rotary shaft 12 that is supported by the bearing 19. The in-shaft passage 47 thus connects the back pressure chamber 45 and the motor chamber 24 to each other.
As shown in
As shown in
The discharge housing member 16 has a discharge chamber defining recess 52 in the end face closest to the intermediate housing member 17. The interior of the discharge chamber defining recess 52 is connected to the connecting passage 51. The discharge housing member 16 has a discharge port 53 and an oil separation chamber 54 connected to the discharge port 53. The discharge housing member 16 further has a passage 55 that connects the interior of the discharge chamber defining recess 52 and the oil separation chamber 54 to each other. The oil separation chamber 54 accommodates an oil separation tube 56.
The intermediate housing member 17 includes an introduction port 60, an accommodating recess 62, and two supply passages 63. Refrigerant of the intermediate pressure from the external refrigerant circuit 25 is introduced into the introduction port 60. The accommodating recess 62 is connected to the introduction port 60. The two supply passages 63 are connected to the accommodating recess 62, and supply the refrigerant of the intermediate pressure in the accommodating recess 62 to the injection ports 50. The accommodating recess 62 is formed in the end face of the intermediate housing member 17 that is closest to the discharge housing member 16. The accommodating recess 62 substantially has a rectangular shape in plan view. The opening of the accommodating recess 62 faces the discharge chamber defining recess 52. The two supply passages 63 open in the bottom surface of the accommodating recess 62.
As shown in
As shown in
The valve plate 71 is flat. The valve plate 71 is made of metal such as iron. The valve plate 71 has an outer shape conforming to the inner surface of the first recess 62a. The valve plate 71 has a single valve hole 71h at the center. The valve hole 71h is rectangular in a plan view. The valve hole 71h extends through the valve plate 71 in the thickness direction. The valve plate 71 has two bolt insertion holes 71a in the outer periphery.
The reed valve forming plate 72 is relatively thin. The reed valve forming plate 72 is made of metal such as iron. The reed valve forming plate 72 has an outer shape conforming to the inner surface of the first recess 62a. The reed valve forming plate 72 has an outer frame 72a and a reed valve 72v. The reed valve 72v protrudes from a part of the inner edge of the outer frame 72a toward the center of the outer frame 72a. The reed valve 72v is plate-shaped and has a trapezoidal shape in a plan view. The distal end of the reed valve 72v has a size capable of covering the valve hole 71h. The reed valve 72v is thus capable of opening and closing the valve hole 71h. The outer frame 72a also has two bolt insertion holes 72h.
The retainer forming plate 73 is relatively thin. The retainer forming plate 73 is made of rubber. The retainer forming plate 73 has an outer shape conforming to the inner surface of the first recess 62a. The retainer forming plate 73 has an outer frame 73a and a retainer 73v. The retainer 73v curves and protrudes from a part of the inner edge of the outer frame 73a. The retainer 73v limits the opening degree of the reed valve 72v. The retainer 73v is accommodated in the second recess 62b. The outer frame 73a also has two bolt insertion holes 73h.
The retainer forming plate 73, the reed valve forming plate 72, and the valve plate 71 are arranged in that order on the bottom surface of the first recess 62a. In a state in which the retainer forming plate 73, the reed valve forming plate 72, and the valve plate 71 are accommodated in the first recess 62a, the bolt insertion holes 71a, 72h, 73h are aligned. The retainer forming plate 73, the reed valve forming plate 72, and the valve plate 71 are fastened to bottom surface of the first recess 62a by inserting fastening bolts 74 into the bolt insertion holes 71a, 72h, 73h and threading the fastening bolts 74 to the internal thread holes 62h.
As shown in
A lid 65 is attached to the intermediate housing member 17 to close the opening of the accommodating recess 62. The lid 65 has a plate-shaped lid bottom wall 65a and a tubular lid peripheral wall 65b, which extends from the outer periphery of the lid bottom wall 65a. The lid 65 has a tubular shape with a closed end. The lid 65 is fastened to the intermediate housing member 17 with fastening bolts 65c. The lid 65 is arranged inside the discharge chamber defining recess 52. A part of the gasket 29 serves as a seal between the lid 65 and the intermediate housing member 17. Accordingly, the gasket 29 serves as a seal between the interior of the accommodating recess 62 and the discharge chamber defining recess 52.
The gasket 29, the discharge chamber defining recess 52, and the lid 65 define a discharge chamber 68. The discharge housing member 16 therefore has the discharge chamber 68. The accommodating recess 62 faces the discharge chamber 68. The lid 65 separates the accommodating recess 62 and the discharge chamber 68 from each other. The discharge chamber 68 is connected to the connecting passage 51. The refrigerant that has been compressed in the compression chambers 33 is discharged to the discharge chamber 68 via the discharge port 31h and the connecting passage 51. Therefore, the refrigerant of the discharge pressure is discharged to the discharge chamber 68 from the compression mechanism 13. The refrigerant that has been discharged to the discharge chamber 68 flows into the oil separation chamber 54 via the passage 55, and the oil separation tube 56 separates oil from the refrigerant in the oil separation chamber 54. The refrigerant, from which oil has been separated, is discharged to the external refrigerant circuit 25 from the discharge port 53.
The valve plate 71 divides the interior of the accommodating recess 62 into a first chamber 621 relatively close to the introduction port 60 and a second chamber 622 relatively close to the supply passages 63. The first chamber 621 is defined by the valve plate 71, the inner surface of the first recess 62a, and the lid 65. The second chamber 622 is defined by the valve plate 71 and the second recess 62b. The outer frame 73a of the retainer forming plate 73 serves as a seal between the first chamber 621 and the second chamber 622. The sealing between the first chamber 621 and the second chamber 622 in the outer frame 73a is ensured by fastening the fastening bolts 74.
As shown in
As shown in
Each second port section 50b connects the associated first port section 50a to the associated supply passage 63. Each second port section 50b has a first end, which is connected to the opening of the associated supply passage 63 on the side opposite to the accommodating recess 62. Each second port section 50b has a second end, which is connected to the end of the associated first port section 50a on the opposite side to the compression chambers 33. The second end of each first port section 50a corresponds to an end of the first port section 50a that is on the side opposite to the compression chambers 33.
Each second port section 50b extends in a direction diagonally intersecting the axis P1 of the associated supply passage 63 and the axis P2 of the associated first port section 50a. Thus, each injection port 50 includes a portion that extends at a predetermined angle with respect to the axis P1 of the associated supply passage 63 and the axis P2 of the associated first port section 50a. The second port sections 50b approach each other from the second ends toward the first ends. Each supply passage 63 is connected to the associated first port section 50a via the associated second port section 50b. A distance H1 between the openings of the two supply passages 63 that are closest to the accommodating recess 62 is less than a distance H2 between the openings of the two injection ports 50 that are closest to the compression chambers 33.
An operation of the present embodiment will now be described.
For example, in a high load operation of the scroll compressor 10, refrigerant of the intermediate pressure is introduced to the introduction port 60 from the external refrigerant circuit 25. This opens the check valve 70. Specifically, when the refrigerant of the intermediate pressure is introduced to the introduction port 60 from the external refrigerant circuit 25, the refrigerant of the intermediate pressure passes through the introduction port 60, enters the first chamber 621 of the accommodating recess 62, and flows toward the valve hole 71h. Therefore, the accommodating recess 62 functions as an intermediate pressure chamber, into which refrigerant of the intermediate pressure is introduced from the external refrigerant circuit 25.
After flowing into the valve hole 71h, the refrigerant of the intermediate pressure flexes the reed valve 72v. This causes the reed valve 72v to open the valve hole 71h, so that the check valve 70 is in an open state. In this state, the refrigerant of the intermediate pressure passes through the valve hole 71h and flows into the second chamber 622 of the accommodating recess 62. The refrigerant of the intermediate pressure is then introduced into two of the compression chambers 33 that are in a compression process via the supply passages 63 and the injection ports 50. The injection ports 50 thus introduce the refrigerant of the intermediate pressure in the accommodating recess 62 into two of the compression chambers 33. This increases the flow rate of the refrigerant introduced to the compression chambers 33, thereby improving the performance of the scroll compressor 10 in the high load operation.
The check valve 70 closes to prevent refrigerant from flowing to the introduction port 60 from the injection ports 50 via the supply passages 63 and the accommodating recess 62. Specifically, when the refrigerant of the intermediate pressure stops being introduced to the introduction port 60 from the external refrigerant circuit 25, the reed valve 72v returns to the original position (i.e. the position before being flexed by the refrigerant of the intermediate pressure). This closes the valve hole 71h, so that the check valve 70 is in a closed state. Accordingly, after flowing from the compression chambers 33 to the injection ports 50, the supply passages 63, and the second chamber 622, the refrigerant is prevented from flowing to the first chamber 621 via the valve hole 71h. This prevents backflow of refrigerant from the introduction port 60 to the external refrigerant circuit 25. That is, the check valve 70 prevents backflow of refrigerant from the compression chambers 33 via the supply passages 63 and the injection ports 50.
In order to increase the flow rate of the refrigerant of the intermediate pressure introduced into the compression chambers 33 from the injection ports 50, the diameter of the injection ports 50 may be increased. However, an increase in the diameter of the injection ports 50 may prevent the openings of the injection ports 50 on the side corresponding to the compression chambers 33 from being completely closed by the movable scroll 32 during a compression process of the scroll compressor 10. This may cause the refrigerant to flow to the second chamber 622 of the accommodating recess 62 from the compression chambers 33 in a compression process via the injection ports 50 and the supply passages 63.
In the present embodiment, the distance H1 between the openings of the two supply passages 63 that are closest to the accommodating recess 62 is less than a distance H2 between the openings of the two injection ports 50 that are closest to the compression chambers 33. This configuration minimizes the volume of the second chamber 622, which is the space in the accommodating recess 62 between the check valve 70 and the supply passages 63, unlike a case in which the distance H1 is greater than or equal to the distance H2. This reduces the flow rate of the refrigerant that flows into the second chamber 622 from the compression chambers 33 in a compression process through the injection ports 50 and the supply passages 63. This limits reduction in the compression efficiency of the scroll compressor 10.
The above-described embodiment has the following advantages.
(1) The distance H1 between the openings of the two supply passages 63 that are closest to the accommodating recess 62 is less than a distance H2 between the openings of the two injection ports 50 that are closest to the compression chambers 33. This configuration minimizes the volume of the space in the accommodating recess 62 between the check valve 70 and the two supply passages 63, unlike a case in which the distance H1 between the openings of the supply passages 63 that are closest to the accommodating recess 62 is greater than or equal to the distance H2 between the openings of the two injection ports 50 that are closest to the compression chambers 33. This reduces the flow rate of the refrigerant that flows into the accommodating recess 62 from the compression chambers 33 in a compression process through the injection ports 50 and the supply passages 63. This limits reduction in the compression efficiency of the scroll compressor 10.
(2) The two injection ports 50 each include a portion that extends in the same direction as and parallel with each of the two supply passages 63. Also, each injection port 50 includes a portion that extends at a predetermined angle with respect to the axis P1 of the associated supply passage 63 and the axis P2 of the associated first port section 50a. This configuration is suitable to cause the distance H1 between the openings of the two supply passages 63 that are closest to the accommodating recess 62 to be less than the distance H2 between the openings of the two injection ports 50 that are closest to the compression chambers 33.
(3) The flange 23 is held by the peripheral wall 17b of the intermediate housing member 17 and the peripheral wall 15b of the motor housing member 15. In this state, the bolts 30 are passed through the intermediate housing member 17 and the flange 23 and are threaded to the peripheral wall 15b of the motor housing member 15, thereby integrally fixing the shaft support housing member 18 to the intermediate housing member 17 and the motor housing member 15. Thus, the shaft support housing member 18 sufficiently receives the fastening force of the bolts 30. The vibration of the shaft support housing member 18 is therefore easily suppressed. Thus, noise caused by vibration of the shaft support housing member 18 is suppressed. Also, the intermediate housing member 17 has the peripheral wall 17b. Thus, the intermediate housing member 17 has a higher stiffness than in a case in which the intermediate housing member 17 does not have the peripheral wall 17b. Therefore, even if the opening and closing actions of the check valve 70 transmit vibrations to the intermediate housing member 17, the vibration of the intermediate housing member 17 is easily suppressed. This suppresses generation of noise due to vibration of the intermediate housing member 17. This suppresses generation of noise in the scroll compressor 10.
(4) The intermediate housing member 17 includes the lid 65, which closes the opening of the accommodating recess 62 and separates the accommodating recess 62 and the discharge chamber 68 from each other. The lid 65 has the tubular lid bottom wall 65a and the tubular lid peripheral wall 65b, which extends from the outer periphery of the lid bottom wall 65a. The lid 65 has a tubular shape with a closed end. This increases the stiffness of the lid 65 as compared to a case in which the lid 65 is flat. Accordingly, the stiffness of the intermediate housing member 17, to which the lid 65 is attached, is further increased. Therefore, even if the opening and closing actions of the check valve 70 transmit vibrations to the intermediate housing member 17, the vibration of the intermediate housing member 17 is further easily suppressed. This further suppresses generation of noise due to vibration of the intermediate housing member 17.
(5) The intermediate housing member 17 has the mount legs 75 protruding from the outer circumferential surface. This structure further increases the stiffness of the intermediate housing member 17 as compared to a case in which the intermediate housing member 17 does not have the mount legs 75 on the outer circumferential surface. Therefore, even if the opening and closing actions of the check valve 70 transmit vibrations to the intermediate housing member 17, the vibration of the intermediate housing member 17 is further easily suppressed. This further suppresses generation of noise due to vibration of the intermediate housing member 17.
(6) The peripheral wall 17b of the intermediate housing member 17 covers the compression mechanism 13 from the outer side in the radial direction of the rotary shaft 12. The peripheral wall 17b of the intermediate housing member 17 thus limits external transmission, from the scroll compressor 10, of noise generated in the compression mechanism 13, such as contact sound of the fixed scroll 31 and the movable scroll 32. This further suppresses generation of noise in the scroll compressor 10.
(7) The lid 65 has a tubular shape with a closed end. This structure increases the volume of the first chamber 621 as compared to a case in which the lid 65 is flat, and thus reduces pulsation of the refrigerant in the first chamber 621. This suppresses generation of noise due to pulsation of the refrigerant. This further suppresses generation of noise in the scroll compressor 10.
The above-described embodiment may be modified as follows. The above-described embodiment and the following modifications can be combined as long as the combined modifications remain technically consistent with each other.
As shown in
As shown in
In one of the two injection ports 50, the first port section 50a and the second port section 50b may be directly connected to each other with the axis P2 of the first port section 50a and the axis P3 of the second port section 50b displaced from each other. In this case, a portion of the second port sections 50b overlaps with the first port sections 50a when viewed in the direction of the axes P2, P3 of the first port section 50a and the second port section 50b.
The other one of the two injection ports 50 (the lower injection port 50 in
The two supply passages 63 may extend to approach each other from the inner surface of the bottom wall 17a of the intermediate housing member 17 toward the bottom surface of the second recess 62b of the accommodating recess 62. Also, in the fixed base plate 31a, the two injection ports 50 may extend to approach each other from the surface that is closest to the movable scroll 32 toward the surface on the side opposite to the movable scroll 32. The injection ports 50 are respectively connected to the supply passages 63. This configuration may be employed to cause the distance H1 between the openings of the two supply passages 63 that are closest to the accommodating recess 62 to be less than the distance H2 between the openings of the two injection ports 50 that are closest to the compression chambers 33.
Like the injection ports 50, each supply passage 63 may include a first port section 50a and a second port section 50b. That is, any configuration may be employed as long as the two injection ports 50 (or 50′ shown in dashed lines) include a portion that extends in the same direction as and parallel with the two supply passages 63, and at least one of the injection ports 50 or the supply passages 63 includes a portion (second port section 50b or section 50b′ (shown in dashed lines), respectfully) that extends at a predetermined angle with respect to an axis extending in the same direction as the supply passages 63. This configuration allows the distance H1 between the openings of the two supply passages 63 that are closest to the accommodating recess 62 to be less than the distance H2 between the openings of the two injection ports 50 that are closest to the compression chambers 33.
The bolt insertion holes 17h do not necessarily need to extend through the peripheral wall 17b of the intermediate housing member 17, but may extend only through the bottom wall 17a of the intermediate housing member 17. That is, the bolts 30, which extend through the intermediate housing member 17 and the flange 23 and are threaded to the motor housing member 15, may extend through the bottom wall 17a of the intermediate housing member 17 and pass through, for example, the inner side of the peripheral wall 17b of the intermediate housing member 17, without extending through the peripheral wall 17b.
The lid 65 does not necessarily need to have a tubular shape with a closed end, but may be flat. That is, the shape of the lid 65 is not particularly limited as long as the lid 65 can close the opening of the accommodating recess 62 and separate the accommodating recess 62 and the discharge chamber 68 from each other.
The number of the mount legs 75, which protrude from the outer circumferential surface of the intermediate housing member 17, may be one.
The mount legs 75 may be omitted from the outer circumferential surface of the intermediate housing member 17.
The scroll compressor 10 may be configured such that the peripheral wall 17b of the intermediate housing member 17 does not cover the compression mechanism 13 from the outer side in the radial direction of the rotary shaft 12. For example, a wall that protrudes from the inner surface of the bottom wall 17a of the intermediate housing member 17 may be used as the fixed volute wall 31b, and the peripheral wall 17b of the intermediate housing member 17 may be used as a fixed outer peripheral wall, which surrounds the fixed volute wall 31b. That is, it suffices if a portion of the intermediate housing member 17 has the function of the fixed scroll 31. In this case, a part of the intermediate housing member 17 that functions as the fixed scroll 31 forms a part of the compression mechanism 13.
The shape of the reed valve 72v is not particularly limited. It suffices if the distal end of the reed valve 72v have a shape capable of opening and closing the valve hole 71h.
The shape of the valve hole 71h is not particularly limited. In this case, the shape of the distal end of the reed valve 72v must be changed to a shape capable of opening and closing the valve hole 71h.
The check valve 70 does not necessarily need to have the reed valve 72v. For example, the check valve 70 may include a spool valve that reciprocates between an opening position and a closing position depending on the relationship between the urging force of a coil spring and the intermediate pressure of the refrigerant from the introduction port 60. That is, the configuration of the check valve 70 is not particularly limited as long as the check valve 70 is capable of opening when the refrigerant of the intermediate pressure is introduced to the introduction port 60 from the external refrigerant circuit 25, and closing to prevent the refrigerant from flowing to the introduction port 60 from the injection ports 50 via the supply passages 63 and the accommodating recess 62.
The shapes of the two injection ports 50 and the two supply passages 63 do not necessarily need to be circular, but may be elliptic or rectangular. That is, the shapes of the two injection ports 50 and the two supply passages 63 are not particularly limited as long as the distance H1 between the openings of the two supply passages 63 that are closest to the accommodating recess 62 is less than the distance H2 between the openings of the two injection ports 50 that are closest to the compression chambers 33.
The scroll compressor 10 does not need to be of a type that is driven by the electric motor 14, but may be of a type that is driven by a vehicle engine.
In the above-described embodiment, the scroll compressor 10 is used in the vehicle air conditioner. However, the scroll compressor 10 may be used in other apparatuses. For example, the scroll compressor 10 may be mounted on a fuel cell vehicle and use the compression mechanism 13 to compress air, which is fluid supplied to the fuel cell.
Various changes in form and details may be made to the examples above without departing from the spirit and scope of the claims and their equivalents. The examples are for the sake of description only, and not for purposes of limitation. Descriptions of features in each example are to be considered as being applicable to similar features or aspects in other examples. Suitable results may be achieved if sequences are performed in a different order, and/or if components in a described system, architecture, device, or circuit are combined differently, and/or replaced or supplemented by other components or their equivalents. The scope of the disclosure is not defined by the detailed description, but by the claims and their equivalents. All variations within the scope of the claims and their equivalents are included in the disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| JP2020-064653 | Mar 2020 | JP | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 20150192126 | Nagano et al. | Jul 2015 | A1 |
| 20150192127 | Nagano | Jul 2015 | A1 |
| Number | Date | Country |
|---|---|---|
| 2015-129468 | Jul 2015 | JP |
| 2015-129475 | Jul 2015 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20210301820 A1 | Sep 2021 | US |
