SCROLL COMPRESSOR

Abstract

A scroll compressor includes a housing, a first scroll, a second scroll being configured to rotate relative to the first scroll about a driving axis of the scroll compressor. The second scroll has an end plate, a spiral element, and an adjustment portion adjusting a center-of-gravity of the second scroll. The adjustment portion has a bottom surface, a peripheral surface enclosing the bottom surface, and a connection surface connecting the bottom surface to the peripheral surface. The peripheral surface has a first peripheral surface and a second peripheral surface. A length of the first peripheral surface in a direction in which the driving axis extends is shorter than a length of the second peripheral surface in the direction in which the driving axis extends.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Japanese Patent Application No. 2022-103204 filed on Jun. 28, 2022, the entire disclosure of which is incorporated herein by reference.

BACKGROUND ART

The present disclosure relates to a scroll compressor.

There is known a scroll compressor disclosed in International Patent Application Publication No. 2018/003032. The scroll compressor includes a housing, a first scroll, and a second scroll. The first scroll is fixed in the housing. The second scroll is disposed in the housing. The second scroll is rotated relative to the first scroll about a driving axis of the scroll compressor to form a compression chamber in which fluid is compressed, between the second scroll and the first scroll.

The second scroll includes an end plate, a spiral element, and a plurality of adjustment portions. The end plate is formed in a disc shape and extends orthogonally to the driving axis. The end plate has a first surface facing the first scroll and a second surface opposite to the first surface. The spiral element is integrally formed with the end plate, and spirally protrudes from the first surface toward the first scroll in a direction in which the driving axis extends. The adjustment portions are formed in the end plate, and recessed from the second surface toward the first surface. That is, the adjustment portions are located opposite to the spiral element in the end plate. The plurality of adjustment portions is formed in the end plate.

In such a scroll compressor, the adjustment portions adjust a center-of-gravity of the second scroll to cause the center-of-gravity of the second scroll to approach the driving axis as closely as possible. As a result, in the scroll compressor, the second scroll is suitably rotated about the driving axis, thereby preventing noise generated during an operation of the scroll compressor.

This type of scroll compressor is required to increase a capacity for compressing fluid. To meet the above needs, it is considered that in the above-described known scroll compressor, the compression chamber, which is formed between the second scroll and the first scroll, is increased in size by increasing a length of the spiral element in the direction in which the driving axis extends (hereinafter simply called the driving axis direction).

However, the increasing of the length of the spiral element in the driving axis direction shifts the center-of-gravity of the second scroll from the driving axis, which causes the second scroll not to be suitably rotated about the driving axis. As a result, noise generated during an operation of the scroll compressor is increased. For that reason, it is necessary that according to the increasing of the length of the spiral element in the driving axis direction, the adjustment portions are formed so as to be further deeply recessed into the end plate to adjust the center-of gravity of the second scroll. The second scroll, which also includes the adjustment portions, is generally formed by casting. As the adjustment portions are formed so as to be recessed further deeply, fluidity of molten metal to form the adjustment portions is reduced, which makes it difficult to produce the adjustment portions and therefore the second scroll. This reduces an efficiency of producing the scroll compressor, and causes an increase in production cost.

The present disclosure has been made in view of the above-described known circumstances and is directed to providing a scroll compressor that is superior in quietness while a capacity for compressing fluid is increased, the scroll compressor being produced at low cost.

SUMMARY

In accordance with an aspect of the present disclosure, there is provided a scroll compressor that includes a housing, a first scroll disposed in the housing, and a second scroll disposed in the housing and facing the first scroll to form a compression chamber between the first scroll and the second scroll The second scroll is configured to rotate relative to the first scroll about a driving axis of the scroll compressor to compress fluid in the compression chamber. The second scroll has an end plate formed in a disc shape extending orthogonally to the driving axis, the end plate having a first surface facing the first scroll and a second surface located opposite to the first surface, a spiral element integrally formed with the end plate and spirally protruding from the first surface toward the first scroll in a direction in which the driving axis extends, and an adjustment portion formed in the end plate and recessed from the second surface toward the first surface, the adjustment portion adjusting a center-of-gravity of the second scroll. The adjustment portion has a bottom surface extending in parallel with the second surface, a peripheral surface enclosing the bottom surface and extending in the direction in which the driving axis extends, and a connection surface located between the bottom surface and the peripheral surface, and connecting the bottom surface to the peripheral surface. The peripheral surface has a first peripheral surface located close to an outer periphery of the end plate and a second peripheral surface located closer to the driving axis than the first peripheral surface and facing the first peripheral surface in a radial direction of the end plate. A length of the first peripheral surface in the direction in which the driving axis extends is shorter than a length of the second peripheral surface in the direction in which the driving axis extends.

In accordance with another aspect of the present disclosure, there is provided a scroll compressor that includes a housing, a first scroll disposed in the housing, and a second scroll disposed in the housing and facing the first scroll to form a compression chamber between the first scroll and the second scroll. The second scroll is configured to rotate relative to the first scroll about a driving axis of the scroll compressor to compress fluid in the compression chamber. The second scroll has an end plate formed in a disc shape extending orthogonally to the driving axis, the end plate having a first surface facing the first scroll and a second surface located opposite to the first surface, a spiral element integrally formed with the end plate and spirally protruding from the first surface toward the first scroll in a direction in which the driving axis extends, and an adjustment portion formed in the end plate and recessed from the second surface toward the first surface, the adjustment portion adjusting a center-of-gravity of the second scroll. The adjustment portion has a bottom surface extending in parallel with the second surface, a peripheral surface enclosing the bottom surface and extending in the direction in which the driving axis extends, and a connection surface located between the bottom surface and the peripheral surface, and connecting the bottom surface to the peripheral surface. The peripheral surface has a first peripheral surface located close to an outer periphery of the end plate and a second peripheral surface located closer to the driving axis than the first peripheral surface and facing the first peripheral surface in a radial direction of the end plate. A length of the second peripheral surface in the direction in which the driving axis extends is shorter than a length of the first peripheral surface in the direction in which the driving axis extends.

Other aspects and advantages of the disclosure will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure, together with objects and advantages thereof, may best be understood by reference to the following description of the embodiments together with the accompanying drawings in which:

FIG. 1 is a cross-sectional view illustrating a scroll compressor according to a first embodiment;

FIG. 2 is a front view illustrating a second scroll which is seen from a front of the second scroll according to the scroll compressor of the first embodiment;

FIG. 3 is a cross-sectional view taken along a line A-A of FIG. 2 according to the scroll compressor of the first embodiment;

FIG. 4 is a cross-sectional view taken along the line A-A of FIG. 2, illustrating an enlarged main part of an adjustment portion according to the scroll compressor of the first embodiment;

FIG. 5 is a cross-sectional view taken along a line B-B of FIG. 2, illustrating an enlarged main part of the adjustment portion according to the scroll compressor of the first embodiment;

FIG. 6 is a cross-sectional view taken along a line C-C of FIG. 2, illustrating an enlarged main part of the adjustment portion according to the scroll compressor of the first embodiment;

FIG. 7 is a schematic view illustrating a process of producing the second scroll according to the scroll compressor of the first embodiment;

FIG. 8 is a front view illustrating a second scroll which is seen from a front of the second scroll according to a scroll compressor of a second embodiment;

FIG. 9 is a cross-sectional view taken along a line D-D of FIG. 8 according to the scroll compressor of the second embodiment;

FIG. 10 is a cross-sectional view taken along the line D-D of FIG. 8, illustrating an enlarged main part of an adjustment portion according to the scroll compressor of the second embodiment;

FIG. 11 is a cross-sectional view taken along a line E-E of FIG. 8, illustrating an enlarged main part of the adjustment portion according to the scroll compressor of the second embodiment;

FIG. 12 is a cross-sectional view taken along a line F-F of FIG. 8, illustrating an enlarged main part of the adjustment portion according to the scroll compressor of the second embodiment;

FIG. 13 is a schematic view illustrating a process of producing the second scroll according to the scroll compressor of the second embodiment;

FIG. 14 is a cross-sectional view illustrating an enlarged main part of an adjustment portion according to a scroll compressor of a third embodiment, similarly to FIG. 4; and

FIG. 15 is a cross-sectional view illustrating an enlarged main part of an adjustment portion according to a scroll compressor of a fourth embodiment, similarly to FIG. 10.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The following will describe a first embodiment to fourth embodiment according to the present disclosure with reference to the drawings. A scroll compressor (hereinafter, simply called the compressor) in each of the first embodiment to the fourth embodiment is mounted on a vehicle (not illustrated), and is one of parts constituting a refrigeration circuit of the vehicle.

First Embodiment

As illustrated in FIG. 1, the compressor of the first embodiment includes a housing 1, a driving shaft 5, an electric motor 7, a fixed scroll 9, and a movable scroll 11. The fixed scroll 9 corresponds to the “first scroll” in the present disclosure. The movable scroll 11 corresponds to the “second scroll” in the present disclosure.

In the present embodiments, an arrow in FIG. 1, which is drawn by a solid line, indicates a front direction and a rear direction of the compressor. In FIG. 3 and the subsequent figures, the front direction and the rear direction of the compressor are shown in correspondence with FIG. 1. The front direction and the rear direction are one example used for convenience of explanation, and a posture of the compressor is changed as appropriate in correspondence with a vehicle on which the compressor is mounted, or the like.

As illustrated in FIG. 1, the housing 1 is formed of a motor housing 13, a compressor housing 14, and a fixed block 15. The motor housing 13 serves as a front portion of the housing 1, and the compressor housing 14 serves as a rear portion of the housing 1.

The motor housing 13 has a front wall 13a and a first peripheral wall 13b. The front wall 13a is located at a front end of the motor housing 13, and extends in a radial direction of the motor housing 13. The first peripheral wall 13b is connected to the front wall 13a, and extends in the rear direction from the front wall 13a. The front wall 13a and the first peripheral wall 13b constitute the motor housing 13 formed in a bottomed tubular shape, which opens in the rear direction. A suction chamber 17 is formed in the motor housing 13.

The motor housing 13 also has a suction opening 13c and a supporting portion 13d. The suction opening 13c is formed in the first peripheral wall 13b, and communicates with the suction chamber 17. The suction opening 13c is connected to an evaporator (not illustrated) through a pipe (not illustrated), and refrigerant gas flowing from the evaporator is sucked into the suction chamber 17 through the suction opening 13c. The refrigerant gas corresponds to the “fluid” in the present disclosure.

The supporting portion 13d protrudes from the front wall 13a into the suction chamber 17. The supporting portion 13d is formed in a cylindrical shape, and has therein a first radial bearing 19. The suction opening 13c may be formed in the front wall 13a.

The compressor housing 14 has a rear wall 14a and a second peripheral wall 14b. The rear wall 14a is located in a rear end of the compressor housing 14, and extends in a radial direction of the compressor housing 14. The second peripheral wall 14b is connected to the rear wall 14a, and extends in the front direction from the rear wall 14a. The rear wall 14a and the second peripheral wall 14b constitute the compressor housing 14 formed in a bottomed tubular shape, which opens in the front direction.

The compressor housing 14 has an oil separation chamber 14c, a first discharge recess 14d, a discharge passage 14e, and a discharge opening 14f. The oil separation chamber 14c is located in a rear portion of the compressor housing 14, and extends in the radial direction of the compressor housing 14. The first discharge recess 14d is located in front of the oil separation chamber 14c in the compressor housing 14, and recessed toward the oil separation chamber 14c. The discharge passage 14e extends in a longitudinal direction of the compressor, and provides communication between the oil separation chamber 14c and the first discharge recess 14d. The discharge opening 14f communicates with an upper end of the oil separation chamber 14c, and opens to the outside of the compressor housing 14. The discharge opening 14f is connected to a condenser (not illustrated) through a pipe.

A separation cylinder 21 is fixed in the oil separation chamber 14c. The separation cylinder 21 has an outer peripheral surface 21a formed in a cylindrical shape. An axis of the outer peripheral surface 21a coincides with an axis of an inner peripheral surface 140 of the oil separation chamber 14c. The outer peripheral surface 21a and the inner peripheral surface 140 constitute a separator. In the oil separation chamber 14c, a filter 23 is disposed below the separation cylinder 21.

The fixed block 15 is formed between the motor housing 13 and the compressor housing 14. The motor housing 13, the fixed block 15, and the compressor housing 14 are fastened by a plurality of bolts 25, which is inserted from the compressor housing 14 to the motor housing 13. While the fixed block 15 is held between the motor housing 13 and the compressor housing 14, the fixed block 15 is fixed to the motor housing 13 and the compressor housing 14. Thus, the fixed block 15 is located between the suction chamber 17 and the movable scroll 11 in the longitudinal direction of the compressor. FIG. 1 illustrates only one bolt 25 of the plurality of bolts 25. A method of fixing the motor housing 13, the compressor housing 14, and the fixed block 15 may be designed as appropriate.

A boss 15a protruding in the front direction is formed in the fixed block 15. The boss 15a has, in an end thereof, an insertion hole 15b. A second radial bearing 27 and a sealing member 29 are disposed in the boss 15a. A suction passage 55 is formed in the fixed block 15. The suction passage 55 is located on a radially outward side of the boss 15a in the fixed block 15, and extends through the fixed block 15 in the longitudinal direction of the compressor. The number of the suction passage 55 may be designed as appropriate.

A plurality of anti-rotation pins 31 is fixed in the fixed block 15. The anti-rotation pins 31 extend in the rear direction from the fixed block 15. FIG. 1 illustrates one of the plurality of anti-rotation pins 31.

The driving shaft 5 is disposed in the housing 1. The driving shaft 5 has a columnar shape extending in the longitudinal direction of the compressor. The driving shaft 5 is formed of a small diameter portion 5a, a large diameter portion 5b, and a taper portion 5c. The small diameter portion 5a is located close to a front end of the driving shaft 5. The large diameter portion 5b is located in a rear of the small diameter portion 5a, and has a larger diameter than that of the small diameter portion 5a. The large diameter portion 5b has, in a rear end thereof, a rear end surface 5d formed in a flat shape. The taper portion 5c is located between the small diameter portion 5a and the large diameter portion 5b. A front end of the taper portion 5c is connected to the small diameter portion 5a. A diameter of the taper portion 5c increases as the taper portion 5c extends in the rear direction, and a rear end of the taper portion 5c is connected to the large diameter portion 5b.

The driving shaft 5, in particular, the small diameter portion 5a of the driving shaft 5, is rotatably supported by the supporting portion 13d of the motor housing 13 through the first radial bearing 19. A rear end portion of the large diameter portion 5b is inserted into the insertion hole 15b of the fixed block 15, and enters the boss 15a. In the boss 15a, the rear end portion of the large diameter portion 5b is rotatably supported by the second radial bearing 27. Thus, the rotary shaft 5 is rotatable about a rotating axis X in the housing 1. The rotating axis X extends in parallel with the longitudinal direction of the compressor. The sealing member 29 is interposed between the fixed block 15 and the driving shaft to form a seal.

In the driving shaft 5, an eccentric pin 50 is fixed to the large diameter portion 5b. The eccentric pin 50 is disposed at a position of the rear end surface 5d, which is shifted from the rotating axis X. The eccentric pin 50 is formed in a columnar shape having a smaller diameter than that of the driving shaft 5, and extends in the rear direction from the rear end surface 5d. An axis of the eccentric pin 50 is referred to as a driving axis O. As described above, the eccentric pin 50 is disposed at the position, which is shifted from the rotating axis X, and thus, the driving axis O is also disposed at the position, which is shifted from the rotating axis X. The driving axis O extends in the longitudinal direction of the compressor in parallel with the rotating axis X. The rear end portion of the large diameter portion 5b is inserted into the insertion hole 15b, and the eccentric pin 50 enter the boss 15a. The eccentric pin 50 is fitted to a bushing 50a in the boss 15a.

Furthermore, in the driving shaft 5, a balance weight 33 is integrally formed with the large diameter portion 5b. The balance weight 33 is disposed at a position distant from the rotating axis X in the large diameter portion 5b. More specifically, the balance weight 33 is disposed at the position distant from the eccentric pin 50 across the rotating axis X.

Although not illustrated in detail, the balance weight 33 is formed in a substantially fan-like plate shape. The balance weight 33 extends in a direction away from the large diameter portion 5b in a radial direction of the driving shaft 5. The radial direction of the driving shaft 5 is a direction orthogonal to the longitudinal direction of the compressor. That is, the balance weight 33 extends from the large diameter portion 5b toward the first peripheral wall 13b of the motor housing 13. The driving shaft 5 is disposed in the housing 1, and the balance weight 33 is located in the suction chamber 17. More specifically, the balance weight 33 is located between the fixed block 15 and the electric motor 7 in the suction chamber 17. The balance weight 33 may be designed in any shape as appropriate.

The electric motor 7 is accommodated in the suction chamber 17. That is, the suction chamber 17 also serves as a motor chamber, which accommodates the electric motor 7. The electric motor 7 is located in front of the balance weight 33 in the suction chamber 17.

The electric motor 7 includes a stator 7a and a rotor 7b. The stator 7a is fixed on an inner peripheral surface of the first peripheral wall 13b. The stator 7a is connected to an inverter (not illustrated) provided outside the motor housing 13.

The stator 7a has a stator core 22 and coil ends 24. The stator core 22 is formed in a cylindrical shape. A coil 26 is wound around the stator core 22. The coil ends 24 are each formed in a ring shape protruding from the stator core 22 to the front and the rear of the stator core 22 in an axial direction of the stator core 22. Each of the coil ends 24 is a part of the coil 26. An inner portion of a rear end portion of the coil end 24 is inclined so as to avoid interference with the balance weight 33.

The rotor 7b is disposed in the stator 7a. The large diameter portion 5b of the driving shaft 5 is press-fitted into the rotor 7b. Thus, the driving shaft 5 is fixed to the rotor 7b. The rotor 7b rotates in the stator 7a, thereby rotating the driving shaft 5 about the rotating axis X.

The fixed scroll 9 is fixed to the compressor housing 14, and disposed in the compressor housing 14. The fixed scroll 9 has a fixed scroll end plate 9a, a fixed scroll peripheral wall 9b, and a fixed scroll spiral element 9c. The fixed scroll end plate 9a is located at a rear end of the fixed scroll 9, and formed in a disc shape extending in the radial direction of the driving shaft 5. The fixed scroll end plate 9a has a front surface 901 and a rear surface 902, and also has a second discharge recess 9d and a discharge port 9e. The front surface 901 is oriented in the front direction, that is, faces the movable scroll 11. The rear surface 902 is located opposite to the front surface 901, and oriented in the rear direction.

The second discharge recess 9d is recessed in the front direction from the rear surface 902. The fixed scroll 9 is fixed to the compressor housing 14, which causes the second discharge recess 9d to face the first discharge recess 14d. Thus, the first discharge recess 14d cooperates with the second discharge recess 9d to form a discharge chamber 35. The discharge chamber 35 communicates with the oil separation chamber 14c through the discharge passage 14e. The discharge port 9e extends in the longitudinal direction of the compressor through the fixed scroll end plate 9a, and communicates with the discharge chamber 35.

A discharge reed valve 39 and a retainer 41 are attached on the fixed scroll end plate 9a with a pin 37. The pin 37, the discharge reed valve 39, and the retainer 41 are disposed in the discharge chamber 35. The discharge reed valve 39 is elastically deformed to open and close the discharge port 9e. The retainer 41 adjusts an amount of elastic deformation of the discharge reed valve 39.

The fixed scroll peripheral wall 9b is connected to the fixed scroll end plate 9a at an outer periphery thereof, and has a cylindrical shape extending in the front direction, that is, toward the movable scroll 11. A suction port 9f is formed in the fixed scroll peripheral wall 9b. The suction port 9f extends through the fixed scroll peripheral wall 9b in a radial direction thereof. Thus, the suction port 9f opens into the compressor housing 14. The fixed scroll spiral element 9c is formed on the front surface 901 of the fixed scroll end plate 9a, and integrally formed with the fixed scroll peripheral wall 9b inside the fixed scroll peripheral wall 9b. The fixed scroll spiral element 9c spirally protrudes from the front surface 901 toward the movable scroll 11, and extends in a direction in which the driving axis O extends (hereinafter, called the driving axis O direction).

An oil supply passage 43 is formed in the fixed scroll 9. The oil supply passage 43 extends through the fixed scroll end plate 9a and the fixed scroll peripheral wall 9b. That is, a rear end of the oil supply passage 43 opens on the rear surface 902 of the fixed scroll end plate 9a, and a front end of the oil supply passage 43 opens on a front end surface of the fixed scroll peripheral wall 9b. The oil supply passage 43 communicates with the oil separation chamber 14c through the filter 23. The oil supply passage 43 may be designed in any shape as appropriate.

The movable scroll 11 is disposed in the compressor housing 14, and located between the fixed scroll 9 and the fixed block 15. The movable scroll 11 has a movable scroll end plate 11a and a movable scroll spiral element 11b. The movable scroll end plate 11a corresponds to the “end plate” in the present disclosure, and the movable scroll spiral element 11b corresponds to the “spiral element” in the present disclosure.

As illustrated in FIGS. 2 and 3, the movable scroll end plate 11a is located at a front end of the movable scroll 11, and formed in a disc shape extending in the radial direction of the driving shaft 5. In other word, the movable scroll end plate 11a is formed in the disc shape extending orthogonally to the rotating axis X and the driving axis O. The movable scroll end plate 11a has a rear surface 111, a front surface 112, and an outer peripheral surface 113. The rear surface 111 corresponds to the “first surface” in the present disclosure, and the front surface 112 corresponds to the “second surface” in the present disclosure. The rear surface 111 is oriented in the rear direction, that is, faces the fixed scroll 9. The front surface 112 is located opposite to the rear surface 111 in the movable scroll end plate 11a, and oriented in the front direction. The outer peripheral surface 113 is located between the rear surface 111 and the front surface 112. The outer peripheral surface 113 extends in parallel with the rotating axis X and the driving axis O and extends around a periphery of the movable scroll end plate 11a in a circumferential direction thereof. The outer peripheral surface 113 is continuous with the rear surface 111 and the front surface 112. That is, the outer peripheral surface 113 serves as an outer edge portion of the movable scroll end plate 11a.

A holding portion 61, three first adjustment portions 63, and six accommodation portions 65 are formed in the movable scroll end plate 11a. Each of the first adjustment portions 63 corresponds to the “adjustment portion” in the present disclosure.

The holding portion 61 is disposed at a center position of the movable scroll end plate 11a, that is, at a position of the movable scroll end plate 11a close to the driving axis O. The holding portion 61 is formed in a cylindrical shape protruding in the front direction from the front surface 112. As illustrated in FIG. 1, in the holding portion 61, the bushing 50a is rotatably supported through a third radial bearing 45. With this configuration, the movable scroll 11 is connected to the driving shaft 5 through the bushing 50a and the eccentric pin 50 at a position, which is shifted from the rotating axis X.

As illustrated in FIG. 2, the first adjustment portions 63 have the same configuration, and are disposed in the circumferential direction of the movable scroll end plate 11a. The first adjustment portions 63 are each formed in a substantially rectangular shape that is recessed from the front surface 112 toward the rear surface 111. More specifically, the first adjustment portions 63 are each formed in the rectangular shape in which a portion closest to an outer periphery of the movable scroll end plate 11a extends longer than a portion closest to the driving axis O in the circumferential direction of the movable scroll end plate 11a. More specifically, the first adjustment portions 63 are each formed in the rectangular shape in which a portion closest to the outer peripheral surface 113 in the radial direction of the movable scroll end plate 11a extends longer than the portion closest to the driving axis O in the circumferential direction of the movable scroll end plate 11a.

Each of the first adjustment portions 63 is formed of a bottom surface 63a, a peripheral surface 63b, and a connection surface 63c. The bottom surface 63a is formed in a substantially rectangular and plane shape that extends in the radial direction of the movable scroll end plate 11a from a portion of the bottom surface 63a close to the outer periphery of the movable scroll end plate 11a toward the driving axis O, and extends in the circumferential direction of the movable scroll end plate 11a. Thus, the bottom surface 63a is a plane extending in parallel with the front surface 112. The bottom surface 63a is located closest to the rear surface 111 in the first adjustment portion 63, and serves as a bottom of the first adjustment portion 63. The portion of the bottom surface 63a close to the outer periphery of the movable scroll end plate 11a extends longer in the circumferential direction of the movable scroll end plate 11a than a portion of the bottom surface 63a close to the driving axis O.

The peripheral surface 63b extends around a periphery of the bottom surface 63a, and encloses the bottom surface 63a. As illustrated in FIG. 3, the peripheral surface 63b extends in the driving axis O direction from the bottom surface 63a. That is, the peripheral surface 63b extends in the front direction from the bottom surface 63a to the front surface 112.

As illustrated in FIG. 2, the peripheral surface 63b has a first peripheral surface 601, a second peripheral surface 602, a third peripheral surface 603, and a fourth peripheral surface 604. The first peripheral surface 601 is located closest to the outer periphery of the movable scroll end plate 11a in the peripheral surface 63b, that is, closest to the outer peripheral surface 113. The second peripheral surface 602 is located closest to the driving axis O in the peripheral surface 63b. The second peripheral surface 602 faces the first peripheral surface 601 in the radial direction of the movable scroll end plate 11a.

The third peripheral surface 603 is located between the first peripheral surface 601 and the second peripheral surface 602 in the peripheral surface 63b, and connects the first peripheral surface 601 to the second peripheral surface 602. In the peripheral surface 63b, the fourth peripheral surface 604 faces the third peripheral surface 603 in the circumferential direction of the movable scroll end plate 11a, and is located between the first peripheral surface 601 and the second peripheral surface 602. The fourth peripheral surface 604 connects the first peripheral surface 601 to the second peripheral surface 602.

In the peripheral surface 63b, the first peripheral surface 601 extends longer in the circumferential direction of the movable scroll end plate 11a than the second peripheral surface 602. As the third peripheral surface 603 and the fourth peripheral surface 604 extend from the first peripheral surface 601 to the second peripheral surface 602, the third peripheral surface 603 and the fourth peripheral surface 604 approach each other in the circumferential direction of the movable scroll end plate 11a.

The connection surface 63c is located between the bottom surface 63a and the peripheral surface 63b, and connects the bottom surface 63a to the peripheral surface 63b. The connection surface 63c has a first connection portion 611, a second connection portion 612, a third connection portion 613, and a fourth connection portion 614.

As illustrated in FIGS. 4 and 5, the first connection portion 611 is located between the bottom surface 63a and the first peripheral surface 601, and connects the bottom surface 63a to the first peripheral surface 601. As illustrated in FIGS. 4 and 6, the second connection portion 612 is located between the bottom surface 63a and the second peripheral surface 602. As illustrated in FIG. 2, the third connection portion 613 is located between the bottom surface 63a and the third peripheral surface 603. The fourth connection portion 614 is located between the bottom surface 63a and the fourth peripheral surface 604. In the connection surface 63c, the first connection portion 611 is located closest to the outer periphery of the movable scroll end plate 11a, and the second connection portion 612 is located closest to the driving axis O.

As illustrated in FIGS. 4 and 5, the first connection portion 611 has a bottom surface side first connection part 611a, a peripheral surface side first connection part 611b, and a first flat part 611c. The bottom surface side first connection part 611a is connected to the bottom surface 63a, and extends to be curved toward the first peripheral surface 601. The peripheral surface side first connection part 611b is connected to the first peripheral surface 601, and extends to be curved toward the bottom surface 63a. The first flat part 611c is located between the bottom surface side first connection part 611a and the peripheral surface side first connection part 611b. The first flat part 611c extends in a flat shape, and connects the bottom surface side first connection part 611a to the peripheral surface side first connection part 611b.

With the bottom surface side first connection part 611a, the peripheral surface side first connection part 611b, and the first flat part 611c, the first connection portion 611 has an overall shape that is upwardly inclined from the bottom surface 63a toward the first peripheral surface 601, and connects the bottom surface 63a to the first peripheral surface 601. In other word, the first connection portion 611 has a shape in which a portion connecting the bottom surface 63a to the first peripheral surface 601 is chamfered, when the first adjustment portion 63 is seen in a cross-section taken along a line A-A of FIG. 2. The cross-section taken along the line A-A corresponds to the reference cross-section in the present disclosure, and the cross-section is a cross-section of the movable scroll end plate 11a extending in the driving axis O direction through the first peripheral surface 601, the second peripheral surface 602, and the driving axis O.

On the other hand, as illustrated in FIGS. 4 and 6, the second connection portion 612 does not have the bottom surface side first connection part 611a, the peripheral surface side first connection part 611b, and the first flat part 611c, unlike the first connection portion 611. When seen in the cross-section taken along the line A-A, as illustrated in FIG. 4, the second connection portion 612 is curved in an arc shape with a predetermined radius of curvature, and connects the bottom surface 63a to the second peripheral surface 602.

The third connection portion 613 and the fourth connection portion 614 illustrated in FIG. 2 are symmetrical to each other in the circumferential direction of the movable scroll end plate 11a. The third connection portion 613 is curved in an arc shape and connects the bottom surface 63a to the third peripheral surface 603, and the fourth connection portion 614 is curved in an arc shape and connects the bottom surface 63a to the fourth peripheral surface 604. Furthermore, the third connection portion 613 and the fourth connection portion 614 are located between the first connection portion 611 and the second connection portion 612 in the radial direction of the movable scroll end plate 11a. Thus, the third connection portion 613 and the fourth connection portion 614 are each connected to the first connection portion 611 and the second connection portion 612.

As illustrated in FIG. 4, in the cross-section taken along the line A-A, the followings are assumed: a first imaginary line Y1 extending straight from the bottom surface 63a toward the outer periphery of the movable scroll end plate 11a; a second imaginary line Y2 extending straight from the first peripheral surface 601 toward the first imaginary line Y1; and a first imaginary arc R1 equal to an arc of the second connection portion 612. The first imaginary arc R1 is in contact with the first imaginary line Y1 and the second imaginary line Y2, and located between the bottom surface 63a and the first peripheral surface 601. As a result, the first connection portion 611, more specifically, the bottom surface side first connection part 611a, the peripheral surface side first connection part 611b, and the first flat part 611c face an intersection M1 of the first imaginary line Y1 and the second imaginary line Y2 across the first imaginary arc R1.

As compared with a case where the bottom surface 63a and the second peripheral surface 602 are connected in an arc shape by the second connection portion 612, the bottom surface 63a and the first peripheral surface 601 are more gently connected by the first connection portion 611. Although not illustrated in detail, the first connection portion 611 is also more gently curved than the third connection portion 613 and the fourth connection portion 614.

Thus, the first connection portion 611 more gently connects the bottom surface 63a to the first peripheral surface 601 than the second connection portion 612 connects the bottom surface 63a to the second peripheral surface 602 in the arc shape, so that the first peripheral surface 601 extends shorter in the driving axis O direction than the second peripheral surface 602. Specifically, while the second peripheral surface 602 extends by a second length L12 from the bottom surface 63a to the front surface 112, the first peripheral surface 601 extends by a first length L11 shorter than the second length L12 from the bottom surface 63a to the front surface 112.

As described above, the third peripheral surface 603 connects the first peripheral surface 601 to the second peripheral surface 602. In addition, the third connection portion 613 connects the first connection portion 611 to the second connection portion 612. This means that in the third connection portion 613, a portion close to the first connection portion 611 more gently connects the bottom surface 63a to the third peripheral surface 603, as compared with a portion close to the second connection portion 612. With these configurations, the third peripheral surface 603 extends by the second length L12 from the bottom surface 63a to the front surface 112 at a connection portion between the third peripheral surface 603 and the second peripheral surface 602, whereas the third peripheral surface 603 extends by the first length L11 from the bottom surface 63a to the front surface 112 at a connection portion between the third peripheral surface 603 and the first peripheral surface 601. That is, a length of the third peripheral surface 603 in the driving axis O direction is gradually decreased from the second length L12 to the first length 11, as the third peripheral surface 603 extends from the second peripheral surface 602 to the first peripheral surface 601. Although not illustrated, a length of the fourth peripheral surface 604 in the driving axis O direction is also gradually decreased from the second length L12 to the first length 11, as the fourth peripheral surface 604 extends from the second peripheral surface 602 to the first peripheral surface 601. The third peripheral surface 603, the fourth peripheral surface 604, the third connection portion 613, and the fourth connection portion 614 may be designed in any shape as appropriate.

As illustrated in FIG. 2, the accommodation portions 65 have the same configuration, and are disposed in the circumferential direction of the movable scroll end plate 11a. The accommodation portions 65 are each formed in a substantially columnar shape that is recessed from the front surface 112 toward the rear surface 111. The number of the first adjustment portions 63 and the number of the accommodation portions 65 formed in the movable scroll end plate 11a may be designed as appropriate.

As illustrated in FIG. 3, the movable scroll spiral element 11b is integrally formed with the rear surface 111 of the movable scroll end plate 11a. The movable scroll spiral element 11b spirally protrudes from the rear surface 111 toward the fixed scroll 9 in the rear direction, that is, in a direction in which the rotating axis X extends and the driving axis O direction. As illustrated in FIG. 1, an air supply port 11d is disposed near a center of the movable scroll spiral element 11b. The air supply port 11d opens at a front end of the movable scroll spiral element 11b, and extends in the longitudinal direction of the compressor to the movable scroll end plate 11a through the movable scroll spiral element 11b. As illustrated in FIGS. 2 and 3, for ease of explanation, the air supply port 11d is not illustrated. This goes for FIGS. 8 and 9 as described later.

In forming such a movable scroll 11, firstly, a preparation process of preparing a first casting mold 81 and a second casting mold 83 illustrated in FIG. 7 is performed. The first casting mold 81 has a first forming surface 81a, and the second casting mold 83 has a second forming surface 83a. When the first casting mold 81 and the second casting mold 83 are clamped while the first forming surface 81a and the second forming surface 83a face each other, a first mold cavity 85 is defined by the first forming surface 81a and the second forming surface 83a.

Here, the second forming surface 83a has a holding portion forming part 831 used for forming the holding portion 61, a first adjustment portion forming part 832 used for forming the first adjustment portions 63, and an accommodation portion forming part 833 used for forming the accommodation portions 65.

A first pouring hole 87 is formed in the first casting mold 81. The first pouring hole 87 is connected to the first mold cavity 85. The first pouring hole 87 is connected to a portion of the first mold cavity 85 to form the outer peripheral surface 113 of the movable scroll end plate 11a, that is, to form an outer peripheral portion of the movable scroll end plate 11a. The first pouring hole 87 may be formed in the second casting mold 83, and connected to the outer peripheral portion of the movable scroll end plate 11a.

Next, a casting process is performed. In the casting process, as indicated by an arrow in FIG. 7, which is drawn by a solid line, molten metal is supplied from the first pouring hole 87, and poured into the first mold cavity 85 through the first pouring hole 87. Here, while the molten metal is pressurized as appropriate by a plunger (not illustrated), the molten metal is poured into the first mold cavity 85. The molten metal poured into the first mold cavity 85 is locally pressurized by a squeeze pin (not illustrated).

The first pouring hole 87 is connected to a portion of the first mold cavity 85 to be the outer peripheral portion of the movable scroll end plate 11a. Accordingly, the molten metal supplied through the first pouring hole 87, in the first mold cavity 85, flows from a portion to form the outer peripheral portion of the movable scroll end plate 11a toward the driving axis O, that is, the center of the movable scroll end plate 11a. Then, when the first mold cavity 85 is filled with the molten metal, the pouring of the molten metal completes. Consequently, the casting process ends.

Next, a finishing process is performed. In the finishing process, the molten metal is cooled and solidified in the first mold cavity 85 to form a preformed workpiece (not illustrated) of the movable scroll 11. Then, when the preformed workpiece is removed from the first mold cavity 85, and a finishing treatment such as polishing is applied on the preformed workpiece, the forming of the movable scroll 11 completes. Consequently, the finishing process ends.

Thus, in the first embodiment, not only the movable scroll spiral element 11b but also the holding portion 61, the first adjustment portions 63, and the accommodation portions 65 are integrally formed with the movable scroll end plate 11a at the same time by casting the movable scroll 11. That is, in the first adjustment portions 63 formed by the casting, as described above, the first adjustment portion forming part 832 of the second forming surface 83a is formed such that the length of the first peripheral surface 601 in the driving axis O direction is shorter than the length of the second peripheral surface 602 in the driving axis O direction, the first connection portion 611 is more gently curved than the second connection portion 612, and the lengths of the third peripheral surface 603 and the fourth peripheral surface 604 in the driving axis O direction are gradually decreased as the third peripheral surface 603 and the fourth peripheral surface 604 extend from the second peripheral surface 602 to the first peripheral surface 601. Although neither described in detail nor illustrated, the fixed scroll 9 is also formed by casting.

As illustrated in FIG. 1, in the compressor housing 14, the fixed scroll spiral element 9c of the fixed scroll 9 and the movable scroll spiral element 11b of the movable scroll 11 are engaged with each other. With this configuration, the fixed scroll end plate 9a, the fixed scroll spiral element 9c, the movable scroll end plate 11a, and the movable scroll spiral element 11b define a compression chamber 49 between the fixed scroll 9 and the movable scroll 11. The compression chamber 49 communicates with the discharge port 9e.

A thrust plate 51 is disposed between the fixed scroll 9 and the fixed block 15, and between the movable scroll 11 and the fixed block 15. The fixed scroll 9 and the movable scroll 11 are in contact with the fixed block 15 through the thrust plate 51. The thrust plate 51 is made of a thin metal plate.

The movable scroll end plate 11a and the thrust plate 51 define a back-pressure chamber 53 in the boss 15a of the fixed block 15. The back-pressure chamber 53 communicates with the air supply port 11d.

In the movable scroll 11, a ring 47 formed in a cylindrical shape is accommodated in each of the accommodation portions 65 of the movable scroll end plate 11a. The rings 47 and the anti-rotation pins 31 are coupled by inserting end portions of the anti-rotation pins 31 to the rings 47, respectively. The anti-rotation pins 31 and the rings 47 constitute an anti-rotation mechanism 16. Thus, the fixed block 15, the thrust plate 51, and the movable scroll 11 are coupled by the anti-rotation mechanism 16.

In this compressor, the electric motor 7 is controlled by the inverter to operate, which rotates the driving shaft 5 about the rotating axis X. The rotation of the driving shaft 5 rotates the movable scroll 11. The rotation of the movable scroll 11 is regulated by the anti-rotation mechanism 16, so that the movable scroll 11 only orbits the driving axis O, which is shifted from the rotating axis X. That is, the movable scroll 11 rotates about the driving axis O relative to the fixed scroll 9. This causes the movable scroll end plate 11a to slide on an end of the fixed scroll spiral element 9c, and causes the movable scroll spiral element 11b to slide relative to the fixed scroll spiral element 9c. With this movement, the refrigerant gas in the suction chamber 17 flows into the suction port 9f through the suction passage 55, and then, is sucked into the compression chamber 49 through the suction port 9f. The compression chamber 49 is reduced in volume by the rotation of the movable scroll 11, thereby compressing the refrigerant gas inside the compression chamber 49.

The refrigerant gas of high pressure, which has been compressed in the compression chamber 49, is discharged to the discharge chamber 35 through the discharge port 9e, and flows from the discharge chamber 35 to the oil separation chamber 14c through the discharge passage 14e. While the refrigerant gas of the high pressure flows between the outer peripheral surface 21a of the separation cylinder 21 and the inner peripheral surface 140 of the oil separation chamber 14c again and again, lubricant oil is separated from the refrigerant gas of the high pressure. Then, the refrigerant gas is discharged from the discharge opening 14f through an inside of the separation cylinder 21.

On the contrary, the lubricant oil separated from the refrigerant gas is stored in the oil separation chamber 14c. The lubricant oil flows into the oil supply passage 43 through the filter 23, and is supplied to a sliding portion between the fixed scroll 9 and the movable scroll 11 to smooth the sliding portion. The lubricant oil flowing through the oil supply passage 43 is also supplied to the suction chamber 17, or the like, in addition to a space between the second radial bearing 27 and the driving shaft 5.

The part of the refrigerant gas of the high pressure, which has been compressed in the compression chamber 49, is supplied to the back-pressure chamber 53 through the air supply port 11d. This increases pressure in the back-pressure chamber 53. As a result, the movable scroll 11 is urged toward the compression chamber 49 through the thrust plate 51 by the pressure in the back-pressure chamber 53. The movable scroll 11 is urged toward the compression chamber 49 also by an elastic force of the thrust plate 51.

In this compressor, in order to increase a size of the compression chamber 49, the fixed scroll spiral element 9c and the movable scroll spiral element 11b are each formed longer in the driving axis O direction, as compared with those of the conventional compressor. With this configuration, the movable scroll 11 has the first adjustment portions 63 that are more deeply recessed into the movable scroll end plate 11a to adjust a center-of-gravity of the movable scroll 11.

In this compressor, in forming the movable scroll 11 by the casting, the molten metal flows from the portion of the first mold cavity 85 to form the outer peripheral portion of the movable scroll end plate 11a toward the driving axis O. That is, the first peripheral surface 601 is located upstream of the second peripheral surface 602 in a flowing direction of the molten metal, and the first connection portion 611 is located upstream of the second connection portion 612 in the flowing direction of the molten metal.

In this compressor, the connection surface 63c of each of the first adjustment portions 63 has the first connection portion 611, the second connection portion 612, the third connection portion 613, and the fourth connection portion 614. Here, the first connection portion 611 connects the first peripheral surface 601 of the peripheral surface 63b to the bottom surface 63a, that is, the first connection portion 611 is located closest to the outer periphery of the movable scroll end plate 11a, of the connection surface 63c. In contrast, the second connection portion 612 connects the second peripheral surface 602 of the peripheral surface 63b to the bottom surface 63a, that is, the second connection portion 612 is located closest to the driving axis O, of the connection surface 63c. As described above, the first connection portion 611 faces the intersection M1 of the first imaginary line Y1 and the second imaginary line Y2 across the first imaginary arc R1, and connects the bottom surface 63a to the first peripheral surface 601 with a gentler curve than that of the second connection portion 612 formed in an arc shape.

While the second peripheral surface 602 extends from the bottom surface 63a to the front surface 112 by the second length L12, the first peripheral surface 601 extends from the bottom surface 63a to the front surface 112 by the first length L11 shorter than the second length L12.

In this compressor, these configurations increase fluidity of the molten metal to form the first peripheral surface 601 and the first connection portion 611 when the movable scroll 11 is casted, as indicated in arrows of FIG. 5, which are drawn by a broken line. In other word, the molten metal suitably flows on portions of the first mold cavity 85 to form the first peripheral surface 601 and the first connection portion 611. For this reason, in this compressor, even when the first adjustment portions 63 are deeply recessed, the first adjustment portions 63 each including the first peripheral surface 601 and the first connection portion 611 are suitably formed.

Thus, in this compressor, the fixed scroll spiral element 9c and the movable scroll spiral element 11b are made longer in the driving axis O direction to increase the compression chamber 49 in size, and the center-of-gravity of the movable scroll 11 is suitably adjusted by the first adjustment portions 63. In addition, in this compressor, the fluidity of the molten metal to form the first peripheral surface 601 and the first connection portion 611 is increased, thereby making it difficult to reduce an efficiency of producing the compressor, even when the first adjustment portions 63 are formed so as to be recessed deeply.

Therefore, the compressor according to the first embodiment is superior in quietness while a capacity for compressing the refrigerant gas is increased, and produced at low cost.

Specifically, in this compressor, the first connection portion 611 has the bottom surface side first connection part 611a, the peripheral surface side first connection part 611b, and the first flat part 611c. With this configuration, when each of the first adjustment portions 63 is seen in the cross-section taken along the line A-A, the first connection portion 611, which connects the bottom surface 63a to the first peripheral surface 601, has the chamfered shape. Due to the first flat part 611c, the fluidity of the molten metal to form the first connection portion 611 is sufficiently increased.

In this compressor, the lengths of the third peripheral surface 603 and the fourth peripheral surface 604 of the peripheral surface 63b in the driving axis O direction are gradually shortened as the third peripheral surface 603 and the fourth peripheral surface 604 extends from the second peripheral surface 602 to the first peripheral surface 601. This also increases the fluidity of the molten metal to form the first peripheral surface 601 and the first connection portion 611.

In this compressor, in forming the first adjustment portions 63, the portion required for securing the fluidity of the molten metal to form the connection surface 63c, that is, the first connection portion 611, is formed in a gentle curve, so that all of the first connection portion 611 to the fourth connection portion 614 need not to be formed in a gentle curve like the first connection portion 611. Accordingly, in this compressor, while the efficiency of producing the compressor is increased as described above, a degree of freedom in design of the connection surface 63c and therefore a degree of freedom in design of the first adjustment portions 63 is also increased. For that reason, each of the first adjustment portions 63 is formed in a shape suitable for adjusting the center-of-gravity of the movable scroll 11. As a result, the center-of-gravity of the movable scroll 11 is suitably adjusted by the first adjustment portions 63, which causes the center-of-gravity of the movable scroll 11 to approach the driving axis O suitably.

Second Embodiment

The compressor of the second embodiment includes a movable scroll 12 illustrated in FIGS. 8 and 9, instead of the movable scroll 11. The movable scroll 12 also corresponds to the “second scroll” in the present embodiment.

The movable scroll 12 has a movable scroll end plate 12a and a movable scroll spiral element 12b. The movable scroll end plate 12a corresponds to the “end plate” in the present disclosure, and the movable scroll spiral element 12b also corresponds to the “spiral element” in the present disclosure. The movable scroll end plate 12a is located at a front end of the movable scroll 12, and formed in a disc shape extending in a radial direction of the driving shaft 5. The movable scroll end plate 12a has a rear surface 121, a front surface 122, and an outer peripheral surface 123. The rear surface 121 also corresponds to the “first surface” in the present disclosure, and the front surface 122 also corresponds to the “second surface” in the present disclosure. The rear surface 121 faces the fixed scroll 9. The front surface 122 is located opposite to the rear surface 121, and oriented in the front direction. The outer peripheral surface 123 is located between the rear surface 121 and the front surface 122. The outer peripheral surface 123 extends in parallel with the rotating axis X and the driving axis O, extends around a periphery of the movable scroll end plate 12a in a circumferential direction thereof, and is continuous with the rear surface 121 and the front surface 122. That is, the outer peripheral surface 123 serves as an outer edge portion of the movable scroll end plate 12a.

As illustrated in FIG. 8, a holding portion 71, three second adjustment portions 73, and six accommodation portions 75 are formed in the movable scroll end plate 12a. Each of the second adjustment portions 73 also corresponds to the “adjustment portion” in the present disclosure. The holding portion 71 and the accommodation portions 75 in the second embodiment have the same configuration as those of the holding portion 61 and the accommodation portions 65 in the first embodiment, except only that the holding portion 71 and the accommodation portions 75 each have a smaller diameter than those of the holding portion 61 and the accommodation portions 65. The number of the second adjustment portions 73 and the number of the accommodation portions 75 may be designed as appropriate.

The second adjustment portions 73 have the same configuration, and are disposed in the circumferential direction of the movable scroll end plate 12a. The second adjustment portions 73 are each formed in a substantially rectangular shape that is recessed from the front surface 122 toward the rear surface 121. More specifically, the second adjustment portions 73 are each formed in a rectangular shape in which a portion closest to the driving axis O extends longer in the circumferential direction of the movable scroll end plate 12a than a portion closest to an outer periphery of the movable scroll end plate 12a. In other word, the second adjustment portions 73 are each formed in the rectangular shape in which a portion closest to the driving axis O in a radial direction of the movable scroll end plate 12a extends longer in the circumferential direction of the movable scroll end plate 12a than a portion closest to the outer peripheral surface 123.

Each of the second adjustment portions 73 is formed of a bottom surface 73a, a peripheral surface 73b, and a connection surface 73c. The bottom surface 73a is formed in a substantially rectangular and plane shape that extends in the radial direction of the movable scroll end plate 12a from a portion of the bottom surface 73a close to the outer periphery of the movable scroll end plate 12a toward the driving axis O, and extends in the circumferential direction of the movable scroll end plate 12a. Thus, the bottom surface 73a is a plane extending in parallel with the front surface 122. The bottom surface 73a is located closest to the rear surface 121 in each of the second adjustment portions 73, and serves as a bottom of the second adjustment portion 73. A portion of the bottom surface 73a close to the driving axis O extends longer in the circumferential direction of the movable scroll end plate 12a than a portion of the bottom surface 73a close to the outer periphery of the movable scroll end plate 12a.

The peripheral surface 73b extends around a periphery of the bottom surface 73a, and encloses the bottom surface 73a. As illustrated in FIG. 10, the peripheral surface 73b extends in the driving axis O direction from the bottom surface 73a.

As illustrated in FIG. 8, the peripheral surface 73b has a first peripheral surface 701, a second peripheral surface 702, a third peripheral surface 703, and a fourth peripheral surface 704. The first peripheral surface 701 is located closest to the outer periphery of the movable scroll end plate 12a, in the peripheral surface 73b, that is, close to the outer peripheral surface 123. The second peripheral surface 702 is located closest to the driving axis O in the peripheral surface 73b. The second peripheral surface 702 faces the first peripheral surface 701 in the radial direction of the movable scroll end plate 12a.

The third peripheral surface 703 is located between the first peripheral surface 701 and the second peripheral surface 702 in the peripheral surface 73b, and connects the first peripheral surface 701 to the second peripheral surface 702. The fourth peripheral surface 704 faces the third peripheral surface 703 in the circumferential direction of the movable scroll end plate 12a in the peripheral surface 73b, and is located between the first peripheral surface 701 and the second peripheral surface 702. The fourth peripheral surface 704 connects the first peripheral surface 701 to the second peripheral surface 702.

In the peripheral surface 73b, the second peripheral surface 702 extends longer in the circumferential direction of the movable scroll end plate 12a than the first peripheral surface 701. As the third peripheral surface 703 and the fourth peripheral surface 704 extend from the second peripheral surface 702 to the first peripheral surface 701, the third peripheral surface 703 and the fourth peripheral surface 704 approach each other in the circumferential direction of the movable scroll end plate 12a.

The connection surface 73c is located between the bottom surface 73a and the peripheral surface 73b, and connects the bottom surface 73a to the peripheral surface 73b. The connection surface 73c has a first connection portion 711, a second connection portion 712, a third connection portion 713, and a fourth connection portion 714.

As illustrated in FIGS. 10 and 11, the first connection portion 711 is located between the bottom surface 73a and the first peripheral surface 701. As illustrated in FIGS. 10 and 12, the second connection portion 712 is located between the bottom surface 73a and the second peripheral surface 702, and connects the bottom surface 73a to the second peripheral surface 702. As illustrated in FIG. 8, the third connection portion 713 is located between the bottom surface 73a and the third peripheral surface 703. The fourth connection portion 714 is located between the bottom surface 73a and the fourth peripheral surface 704. In the connection surface 73c, the first connection portion 711 is located closest to the outer periphery of the movable scroll end plate 12a, and the second connection portion 712 is located closest to the driving axis O.

As illustrated in FIGS. 10 and 12, the second connection portion 712 has a bottom surface side second connection part 712a, a peripheral surface side second connection part 712b, and a second flat part 712c. The bottom surface side second connection part 712a is connected to the bottom surface 73a, and extends to be curved toward the second peripheral surface 702. The peripheral surface side second connection part 712b is connected to the second peripheral surface 702, and extends to be curved toward the bottom surface 73a. The second flat part 712c is located between the bottom surface side second connection part 712a and the peripheral surface side second connection part 712b. The second flat part 712c extends in a flat shape, and connects the bottom surface side second connection part 712a to the peripheral surface side second connection part 712b.

With the bottom surface side second connection part 712a, the peripheral surface side second connection part 712b, and the second flat part 712c, the second connection portion 712 has an overall shape that is upwardly inclined from the bottom surface 73a toward the second peripheral surface 702, and connects the bottom surface 73a to the second peripheral surface 702. In other word, the second connection portion 712 has a shape in which a portion connecting the bottom surface 73a to the second peripheral surface 702 is chamfered, when the second adjustment portion 73 is seen in a cross-section taken along a line D-D of FIG. 8. The cross-section taken along the line D-D also corresponds to the reference cross-section in the present disclosure, and the cross-section is a cross-section of the movable scroll end plate 12a extending in the driving axis O direction through the first peripheral surface 701, the second peripheral surface 702, and the driving axis O.

On the other hand, as illustrated in FIGS. 10 and 11, unlike the second connection portion 712, the first connection portion 711 does not have the bottom surface side second connection part 712a, the peripheral surface side second connection part 712b, and the second flat part 712c. Accordingly, as illustrated in FIG. 10, the first connection portion 711 is curved in an arc shape with a predetermined radius of curvature, when seen in the cross-section taken along the line D-D, and connects the bottom surface 73a to the first peripheral surface 701.

The third connection portion 713 and the fourth connection portion 714 illustrated in FIG. 8 are symmetrical to each other in the circumferential direction of the movable scroll end plate 12a. The third connection portion 713 is curved in an arc shape and connects the bottom surface 73a to the third peripheral surface 703, and the fourth connection portion 714 is curved in an arc shape and connects the bottom surface 73a to the fourth peripheral surface 704. Furthermore, the third connection portion 713 and the fourth connection portion 714 are located between the first connection portion 711 and the second connection portion 712 in the radial direction of the movable scroll end plate 12a. Thus, the third connection portion 713 and the fourth connection portion 714 are each connected to the first connection portion 711 and the second connection portion 712.

As illustrated in FIG. 10, in the cross-section taken along the line D-D, the followings are assumed: a third imaginary line Y3 extending straight from the bottom surface 73a toward the driving axis O; a fourth imaginary line Y4 extending straight from the second peripheral surface 702 toward the third imaginary line Y3; and a second imaginary arc R2 equal to an arc of the first connection portion 711. The second imaginary arc R2 is in contact with the third imaginary line Y3 and the fourth imaginary line Y4, and located between the bottom surface 73a and the second peripheral surface 702. As a result, the second connection portion 712, more specifically, the bottom surface side second connection part 712a, the peripheral surface side second connection part 712b, and the second flat part 712c face an intersection M2 of the third imaginary line Y3 and the fourth imaginary line Y4 across the second imaginary arc R2.

As compared with a case where the bottom surface 73a and the first peripheral surface 701 are connected by the first connection portion 711 in an arc shape, the bottom surface 73a and the second peripheral surface 702 are more gently connected by the second connection portion 712. Although not illustrated in detail, the second connection portion 712 is more gently curved than the third connection portion 713 and the fourth connection portion 714.

Thus, the second connection portion 712 more gently connects the bottom surface 73a to the second peripheral surface 702 than the first connection portion 711 connects the bottom surface 73a to the first peripheral surface 701 in an arc shape, so that the second peripheral surface 702 extends shorter in the driving axis O direction than the first peripheral surface 701. Specifically, while the first peripheral surface 701 extends by a fourth length L14 from the bottom surface 73a to the front surface 122, the second peripheral surface 702 extends by a third length L13 shorter than the fourth length L14 from the bottom surface 73a to the front surface 122.

As described above, the third peripheral surface 703 connects the first peripheral surface 701 to the second peripheral surface 702. In addition, the third connection portion 713 connects the first connection portion 711 to the second connection portion 712. This means that in the third connection portion 713, a portion close to the second connection portion 712 more gently connects the bottom surface 73a to the third peripheral surface 703, as compared with a portion close to the first connection portion 711. With these configurations, the third peripheral surface 703 extends by the third length L13 from the bottom surface 73a to the front surface 122 at a connection portion between the third peripheral surface 703 and the second peripheral surface 702, whereas the third peripheral surface 703 extends by the fourth length L14 from the bottom surface 73a to the front surface 122 at a connection portion between the third peripheral surface 703 and the first peripheral surface 701. That is, a length of the third peripheral surface 703 in the driving axis O direction is gradually decreased from the fourth length L14 to the third length L13, as the third peripheral surface 703 extends from the first peripheral surface 701 to the second peripheral surface 702. Although not illustrated, a length of the fourth peripheral surface 704 in the driving axis O direction is also gradually decreased from the fourth length L14 to the third length L13, as the fourth peripheral surface 704 extends from the first peripheral surface 701 to the second peripheral surface 702. The third peripheral surface 703, the fourth peripheral surface 704, the third connection portion 713, and the fourth connection portion 714 may be designed in any shape as appropriate.

As illustrated in FIG. 9, the movable scroll spiral element 12b is integrally formed with the rear surface 121 of the movable scroll end plate 12a. The movable scroll spiral element 12b spirally protrudes from the rear surface 121 toward the fixed scroll 9 in the direction in which the rotating axis X extends and the driving axis O direction. The other configurations of the movable scroll spiral element 12b are the same as those of the movable scroll spiral element 11b in the first embodiment, and the detail description thereof is omitted.

Similarly to the movable scroll 11 in the first embodiment, the movable scroll 12 is also formed by a preparation process, a casting process, and a finishing process. Specifically, in the preparation process, a third casting mold 91 and a fourth casting mold 93 illustrated in FIG. 13 are prepared. The third casting mold 91 has a third forming surface 91a, and the fourth casting mold 93 has a fourth forming surface 93a. When the third casting mold 91 and the fourth casting mold 93 are clamped while the third forming surface 91a and the fourth forming surface 93a face each other, a second mold cavity 95 is defined by the third forming surface 91a and the fourth forming surface 93a.

The fourth forming surface 93a has a holding portion forming part 931 used for forming the holding portion 71, a second adjustment portion forming portion 932 used for forming the second adjustment portions 73, and an accommodation portion forming part 933 used for forming the accommodation portions 75.

A second pouring hole 97 is formed in the fourth casting mold 93. The second pouring hole 97 is connected to a portion of the second mold cavity 95 close to the driving axis O, that is, a portion of the movable scroll end plate 12a closer to the driving axis O than the outer periphery of the movable scroll end plate 12a.

Then, in the casting process, molten metal is supplied from the second pouring hole 97, and poured into the second mold cavity 95. Here, while the molten metal is pressurized as appropriate by a plunger (not illustrated), the molten metal is poured into the second mold cavity 95. The molten metal poured into the second mold cavity 95 is locally pressurized by a squeeze pin (not illustrated).

The second pouring hole 97 is connected to the portion of the second mold cavity 95 close to the driving axis O. Accordingly, the molten metal supplied through second pouring hole 97, in the second mold cavity 95, flows from a portion to form the movable scroll end plate 12a close to the driving axis O, that is, the center of the movable scroll end plate 12a, toward the outer periphery of the movable scroll end plate 12a. Then, in the finishing process, the molten metal is cooled and solidified in the second mold cavity 95 to form a preformed workpiece (not illustrated) of the movable scroll 12. Then, similarly to the movable scroll 11 in the first embodiment, when a finishing treatment is applied on the preformed workpiece, the forming of the movable scroll 12 completes.

Thus, also in the second embodiment, not only the movable scroll spiral element 12b but also the holding portion 71, the second adjustment portion 73, and the accommodation portions 75 are integrally formed with the movable scroll end plate 12a at the same time by casting the movable scroll 12. That is, in the second adjustment portion 73 formed by the casting, as described above, the second adjustment portion forming portion 932 of the fourth forming surface 93a is formed such that the length of the second peripheral surface 702 in the driving axis O direction is shorter than the length of the first peripheral surface 701 in the driving axis O direction, the second connection portion 712 is more gently curved than the first connection portion 711, and the lengths of the third peripheral surface 703 and the fourth peripheral surface 704 in the driving axis O direction are gradually decreased as the third peripheral surface 703 and the fourth peripheral surface 704 extend from first peripheral surface 701 to the second peripheral surface 702. The other configurations of this compressor are the same as those of the compressor in the first embodiment, and the detailed description thereof will be omitted.

In this compressor, in forming the movable scroll 12 by the casting, the molten metal flows from the portion of the second mold cavity 95 to form a portion of the movable scroll end plate 12a close to the driving axis O toward the outer periphery of the movable scroll end plate 12a. That is, in the peripheral surface 73b, the second peripheral surface 702 is located upstream of the first peripheral surface 701 in a flowing direction of the molten metal, and in the connection surface 73c, the second connection portion 712 is located upstream of the first connection portion 711 in the flowing direction of the molten metal. Here, the second connection portion 712 faces the intersection M2 of the third imaginary line Y3 and the fourth imaginary line Y4 across the second imaginary arc R2, and connects the bottom surface 73a to the second peripheral surface 702 with a gentler curve than that of the first connection portion 711 formed in an arc shape.

While the first peripheral surface 701 extends from the bottom surface 73a to the front surface 122 by the fourth length L14, the second peripheral surface 702 extends from the bottom surface 73a to the front surface 122 by the third length L13 shorter than the fourth length L14.

In this compressor, these configurations increase fluidity of the molten metal to form the second peripheral surface 702 and the second connection portion 712 when the movable scroll 12 is casted, as indicated in arrows of FIG. 12, which are drawn by a broken line. In other word, the molten metal suitably flows on portions of the second mold cavity 95 to form the second peripheral surface 702 and the second connection portion 712. For this reason, in this compressor, even when the second adjustment portions 73 are deeply recessed, the second adjustment portions 73 each including the second peripheral surface 702 and the second connection portion 712 are suitably formed.

In this compressor, the second connection portion 712 has the bottom surface side second connection part 712a, the peripheral surface side second connection part 712b, and the second flat part 712c. With this configuration, when each of the second adjustment portions 73 is seen in the cross-section taken along the line D-D, the second connection portion 712, which connects the bottom surface 73a to the second peripheral surface 702, has the chamfered shape. Due to the second flat part 712c, the fluidity of the molten metal to form the second connection portion 712 is sufficiently increased. The other effects of this compressor are the same as those of the compressor in the first embodiment.

Third Embodiment

As illustrated in FIG. 14, in the compressor according to the third embodiment, the connection surface 63c has a first connection portion 615, instead of the first connection portion 611. That is, in this compressor, the connection surface 63c has the first connection portion 615, the second connection portion 612, the third connection portion 613, and the fourth connection portion 614. Thus, the third connection portion 613 and the fourth connection portion 614 are each connected to the first connection portion 615 and the second connection portion 612.

The first connection portion 615, when seen in the cross-section taken along the line A-A, is curved in an arc shape with a radius of curvature larger than that of the second connection portion 612, and connects the bottom surface 63a to the first peripheral surface 601. Accordingly, the first connection portion 615 faces the intersection M1 of the first imaginary line Y1 and the second imaginary line Y2 across the first imaginary arc R1. The first connection portion 615 is more gently curved than the second connection portion 612. The other configurations of this compressor are the same as those of the compressor in the first embodiment.

As described above, since the first connection portion 615 is more gently curved than the second connection portion 612, also in this compressor in the third embodiment, similarly to the compressor in the first embodiment, while the second peripheral surface 602 extends from the bottom surface 63a to the front surface 112 by the second length L12, the first peripheral surface 601 extends from the bottom surface 63a to the front surface 112 by the first length L11 shorter than the second length L12. In addition, in the third connection portion 613, a portion close to the first connection portion 615 more gently connects the bottom surface 63a to the third peripheral surface 603, as compared with a portion close to the second connection portion 612. Similarly, also in the fourth connection portion 614, a portion close to the first connection portion 615 more gently connects the bottom surface 63a to the fourth peripheral surface 604, as compared with a portion close to the second connection portion 612. That is, lengths of the third peripheral surface 603 and the fourth peripheral surface 604 are gradually decreased from the second length L12 to the first length L11, as the third peripheral surface 603 and the fourth peripheral surface 604 extend from the second peripheral surface 602 to the first peripheral surface 601.

As a result, also in this compressor, in forming the movable scroll 11 by the casting, when molten metal flows from the portion of the first mold cavity 85 to form the outer peripheral portion of the movable scroll end plate 11a toward the driving axis O, fluidity of the molten metal to form the first peripheral surface 601 and the first connection portion 615 is increased. The other effects of this compressor are the same as those of the compressor in the first embodiment.

Fourth Embodiment

As illustrated in FIG. 15, in the compressor according to the fourth embodiment, the connection surface 73c has a second connection portion 715, instead of the second connection portion 712. That is, in this compressor, the connection surface 73c has the first connection portion 711, the second connection portion 715, the third connection portion 713, and the fourth connection portion 714. Thus, the third connection portion 713 and the fourth connection portion 714 are each connected to the first connection portion 711 and the second connection portion 715.

The second connection portion 715, when seen in the cross-section taken along the line D-D, is curved in an arc shape with a radius of curvature larger than that of the first connection portion 711, and connects the bottom surface 73a to the second peripheral surface 702. Accordingly, the second connection portion 715 faces the intersection M2 of the third imaginary line Y3 and the fourth imaginary line Y4 across the second imaginary arc R2. The second connection portion 715 is more gently curved than the first connection portion 711. The other configurations of this compressor are the same as those of the compressor in the second embodiment.

As described above, since the second connection portion 715 is more gently curved than the first connection portion 711, also in this compressor in the fourth embodiment, similarly to the compressor in the second embodiment, while the first peripheral surface 701 extends from the bottom surface 73a to the front surface 122 by the fourth length L14, the second peripheral surface 702 extends from the bottom surface 73a to the front surface 122 by the third length L13 shorter than the fourth length L14. In addition, in the third connection portion 713, a portion close to the second connection portion 715 more gently connects the bottom surface 73a to the third peripheral surface 703, as compared with a portion close to the first connection portion 711. Similarly, also in the fourth connection portion 714, a portion close to the second connection portion 715 more gently connects the bottom surface 73a to the fourth peripheral surface 704, as compared with a portion close to the first connection portion 711. That is, lengths of the third peripheral surface 703 and the fourth peripheral surface 704 are gradually decreased from the fourth length L14 to the third length L13, as the third peripheral surface 703 and the fourth peripheral surface 704 extend from the first peripheral surface 701 to the second peripheral surface 702.

As a result, also in this compressor, in forming the movable scroll 12 by the casting, when molten metal flows from the portion of the second mold cavity 95 to form the movable scroll end plate 11a close to the driving axis O toward the outer periphery of the movable scroll end plate 12a, fluidity of the molten metal to form the second peripheral surface 702 and the second connection portion 715 is increased. The other effects of this compressor are the same as those of the compressor in the first embodiment.

The present disclosure is not limited to the above-described first embodiment to fourth embodiment, and may be modified as appropriate within the gist of the disclosure.

For example, in the compressor in each of the first embodiment to the fourth embodiment, the fixed scroll 9 corresponds to the “first scroll” in the present disclosure. However, the present disclosure is not limited to this aspect, and the present disclosure may have a configuration in which the movable scrolls 11, 12 rotate about the driving axis O relative to the first scroll rotating about the rotating axis X.

In the compressor of each of the first embodiment and the third embodiment, the first connection portions 611, 615 and the second connection portion 612 may be designed in any shape as appropriate, as long as the length of the first peripheral surface 601 in the driving axis O direction is shorter than the length of the second peripheral surface 602 in the driving axis O direction. Similarly, in the compressor of each of the second embodiment and the fourth embodiment, as long as the length of the second peripheral surface 702 in the driving axis O direction is shorter than the length of the first peripheral surface 701 in the driving axis O direction, the first connection portion 711 and the second connection portions 712, 715 may be designed in any shape as appropriate.

In the compressor of each of the first embodiment and the third embodiment, the lengths of the third peripheral surface 603 and the fourth peripheral surface 604 in the driving axis O direction may be decreased step by step, as the third peripheral surface 603 and the fourth peripheral surface 604 extend from the second peripheral surface 602 to the first peripheral surface 601. Similarly, in the compressor of each of the second embodiment and the fourth embodiment, the lengths of the third peripheral surface 703 and the fourth peripheral surface 704 in the driving axis O direction may be decreased step by step, as the third peripheral surface 703 and the fourth peripheral surface 704 extend from the first peripheral surface 701 to the second peripheral surface 702.

In the compressor of each of the first embodiment to the fourth embodiment, the plurality of rings 47 and the plurality of anti-rotation pins 31 constitute the anti-rotation mechanism 16. However, the present disclosure is not limited to this aspect, and the anti-rotation mechanism 16 may be configured in other ways.

In the compressor of each of the first embodiment to the fourth embodiment, the refrigerant gas as the fluid is compressed in the compression chamber 49. However, the present disclosure is not limited to this aspect, fluid such as air supplied to a fuel cell may be compressed in the compression chamber 49.

INDUSTRIAL APPLICABILITY

The present disclosure is usable for an air conditioner in a vehicle, or the like.

Claims

1. A scroll compressor comprising: a housing;a first scroll disposed in the housing; anda second scroll disposed in the housing and facing the first scroll to form a compression chamber between the first scroll and the second scroll, the second scroll being configured to rotate relative to the first scroll about a driving axis of the scroll compressor to compress fluid in the compression chamber,the second scroll having: an end plate formed in a disc shape extending orthogonally to the driving axis, the end plate having a first surface facing the first scroll and a second surface located opposite to the first surface;a spiral element integrally formed with the end plate and spirally protruding from the first surface toward the first scroll in a direction in which the driving axis extends; andan adjustment portion formed in the end plate and recessed from the second surface toward the first surface, the adjustment portion adjusting a center-of-gravity of the second scroll, whereinthe adjustment portion has: a bottom surface extending in parallel with the second surface;a peripheral surface enclosing the bottom surface and extending in the direction in which the driving axis extends; anda connection surface located between the bottom surface and the peripheral surface, and connecting the bottom surface to the peripheral surface,the peripheral surface has a first peripheral surface located close to an outer periphery of the end plate and a second peripheral surface located closer to the driving axis than the first peripheral surface and facing the first peripheral surface in a radial direction of the end plate, anda length of the first peripheral surface in the direction in which the driving axis extends is shorter than a length of the second peripheral surface in the direction in which the driving axis extends.

2. The scroll compressor according to claim 1, wherein the connection surface has a first connection portion connecting the bottom surface to the first peripheral surface, andthe first connection portion has: a bottom surface side first connection part connected to the bottom surface and extending to be curved toward the first peripheral surface;a peripheral surface side first connection part connected to the first peripheral surface and extending to be curved toward the bottom surface; anda first flat part located between the bottom surface side first connection part and the peripheral surface side first connection part, extending in a flat shape, and connecting the bottom surface side first connection part to the peripheral surface side first connection part.

3. The scroll compressor according to claim 1, wherein a cross-section of the end plate extending in the direction in which the driving axis extends through the first peripheral surface, the second peripheral surface, and the driving axis is defined as a reference cross-section,the connection surface has a first connection portion connecting the bottom surface to the first peripheral surface, andthe first connection portion is formed in an arc shape when seen in the reference cross-section.

4. The scroll compressor according to claim 1, wherein the peripheral surface has a third peripheral surface connecting the first peripheral surface to the second peripheral surface, anda length of the third peripheral surface in the direction in which the driving axis extends is gradually decreased as the third peripheral surface extends from the second peripheral surface to the first peripheral surface.

5. A scroll compressor, comprising: a housing;a first scroll disposed in the housing; anda second scroll disposed in the housing and facing the first scroll to form a compression chamber between the first scroll and the second scroll, the second scroll being configured to rotate relative to the first scroll about a driving axis of the scroll compressor to compress fluid in the compression chamber,the second scroll having: an end plate formed in a disc shape extending orthogonally to the driving axis, the end plate having a first surface facing the first scroll and a second surface located opposite to the first surface;a spiral element integrally formed with the end plate and spirally protruding from the first surface toward the first scroll in a direction in which the driving axis extends; andan adjustment portion formed in the end plate and recessed from the second surface toward the first surface, the adjustment portion adjusting a center-of-gravity of the second scroll, whereinthe adjustment portion has: a bottom surface extending in parallel with the second surface;a peripheral surface enclosing the bottom surface and extending in the direction in which the driving axis extends; anda connection surface located between the bottom surface and the peripheral surface, and connecting the bottom surface to the peripheral surface,the peripheral surface has a first peripheral surface located close to an outer periphery of the end plate and a second peripheral surface located closer to the driving axis than the first peripheral surface and facing the first peripheral surface in a radial direction of the end plate, anda length of the second peripheral surface in the direction in which the driving axis extends is shorter than a length of the first peripheral surface in the direction in which the driving axis extends.

6. The scroll compressor according to claim 5, wherein the connection surface has a second connection portion connecting the bottom surface to the second peripheral surface, andthe second connection portion has: a bottom surface side second connection part connected to the bottom surface, and extending to be curved toward the second peripheral surface;a peripheral surface side second connection part connected to the second peripheral surface, and extending to be curved toward the bottom surface; anda second flat part located between the bottom surface side second connection part and the peripheral surface side second connection part, extending in a flat shape, and connecting the bottom surface side second connection part to the peripheral surface side second connection portion.

7. The scroll compressor according to claim 5, wherein a cross-section of the end plate extending in the direction in which the driving axis extends through the first peripheral surface, the second peripheral surface, and the driving axis is defined as a reference cross-section,the connection surface has a second connection portion connecting the bottom surface to the second peripheral surface, andthe second connection portion is formed in an arc shape when seen in the reference cross-section.

8. The scroll compressor according to claim 5, wherein the peripheral surface has a third peripheral surface connecting the first peripheral surface to the second peripheral surface, anda length of the third peripheral surface in the direction in which the driving axis extends is gradually decreased as the third peripheral surface extends from the first peripheral surface to the second peripheral surface.