JP6394888B2 - Scroll compressor - Google Patents

Description

  The present invention relates to a scroll compressor.

  For example, as disclosed in Patent Document 1, a scroll compressor generally includes a fixed scroll fixed to a housing and a movable scroll that revolves with respect to the fixed scroll. The fixed scroll has a fixed side substrate and a fixed side spiral wall erected from the fixed side substrate, and the movable scroll has a movable side substrate and a movable side vortex wall erected from the movable side substrate. . The fixed-side spiral wall and the movable-side spiral wall are meshed with each other, so that a compression chamber is defined in which the volume is reduced and the refrigerant is compressed based on the revolving motion of the movable scroll.

  A rotating shaft is rotatably supported by the housing. The rotating shaft is provided with an eccentric shaft that protrudes toward the movable scroll. The rotation axis of the eccentric shaft is set at a position eccentric with respect to the rotation axis of the rotation shaft. A bush with an integrated balance weight is fitted to the eccentric shaft. The balance weight cancels the centrifugal force acting on the movable scroll when the movable scroll revolves and reduces the amount of unbalance of the movable scroll. An eccentric hole is formed in the bush at a position eccentric with respect to the center of the bush, and the bush can be rotated (swinged) around the eccentric shaft by fitting the eccentric shaft into the eccentric hole. It has become.

  A cylindrical boss portion into which a bush is fitted through a bearing is protruded from the movable side substrate. The center of the movable substrate coincides with the center of the bush. Further, the center of the bush is located on the outer side in the radial direction of the rotation shaft with respect to the rotation axis of the rotation shaft. The distance between the center of the bush and the rotation axis of the rotation shaft is the revolution radius of the movable scroll. The revolution radius of the orbiting scroll varies as the bush swings around the eccentric shaft and the distance between the center of the bush and the rotation axis of the rotating shaft changes. As described above, the eccentric shaft, the bush, and the bearing constitute a so-called driven crank mechanism that varies the revolution radius of the movable scroll. Such a driven crank mechanism is already known.

  By the way, the movable scroll and the fixed scroll have minute processing errors and assembly errors, so that a backlash (gap) is provided in advance between the movable-side spiral wall and the fixed-side spiral wall. Then, when the rotation shaft rotates in the positive direction and the bush swings around the eccentric shaft based on the compression reaction force acting on the movable scroll, the distance between the center of the bush and the rotation axis of the rotation shaft increases. The revolution radius of the movable scroll increases. According to this, the movable-side spiral wall can be brought into contact with the fixed-side spiral wall, and the movable scroll revolves while the movable-side spiral wall is in contact with the fixed-side spiral wall, so that the refrigerant leaks from the compression chamber. Is suppressed.

  On the other hand, when assembling the movable scroll to the fixed scroll, the bush is swung around the eccentric shaft in the direction opposite to that when the rotating shaft rotates in the forward direction. Then, the distance between the center of the bush and the rotation axis of the rotating shaft is reduced, and the revolution radius of the movable scroll is reduced. According to this, the relative position of the movable-side spiral wall with respect to the fixed-side spiral wall can be set to a position where the movable-side spiral wall does not contact the fixed-side spiral wall, and the movable scroll can be easily made with respect to the fixed scroll. It can be assembled.

JP 2013-204568 A

  By the way, in particular, when the centrifugal force acting on the movable scroll increases as during high-speed rotation, the amount of unbalance of the movable scroll increases, and the noise during the revolving motion of the movable scroll increases. Therefore, in order to suppress this noise, it is desired to increase the physique of the balance weight and reduce the unbalance amount of the movable scroll.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to reduce the amount of imbalance of the movable scroll without increasing the size of the scroll compressor.

  A scroll compressor that solves the above-described problems is a fixed scroll that is fixed to a housing and has a fixed spiral wall, a movable scroll that has a movable spiral wall meshing with the fixed spiral wall, and the fixed scroll in the movable scroll. A compression chamber that compresses the refrigerant by reducing the volume based on a revolving motion with respect to the scroll, a rotary shaft that is rotatably supported by the housing, and a position that is eccentric with respect to the rotation axis of the rotary shaft toward the movable scroll. A scroll type compressor comprising: an eccentric shaft that protrudes; a bush fitted to the eccentric shaft and rotatable about the eccentric shaft; and a balance weight provided integrally with the bush. The housing has an inner peripheral surface centered on the rotation axis of the rotation shaft and accommodates the balance weight. The balance weight includes a first virtual circle centered on the center of the bush, at least near the rotation direction of the bush where the distance between the center of the bush and the rotation axis of the rotation shaft decreases. Further, it has a protruding portion protruding outward in the radial direction.

  For example, consider a case where the entire outer peripheral surface of the balance weight extends along a first virtual circle centered on the center of the bush. In order to suppress the leakage of the refrigerant from the compression chamber, it is preferable to bring the movable side spiral wall into contact with the fixed side spiral wall. Therefore, the bush rotates around the eccentric shaft in the rotation direction of the bush, where the distance between the center of the bush and the rotation axis of the rotating shaft increases until the movable spiral wall contacts the fixed spiral wall. As a result, the gap between the bushing in the outer peripheral surface of the balance weight where the distance between the center of the bush and the rotation axis of the rotating shaft increases and the inner peripheral surface of the housing wall becomes smaller.

  On the other hand, in order to assemble the movable scroll with respect to the fixed scroll, the movable-side spiral wall needs to be positioned so as not to contact the fixed-side spiral wall. Therefore, when the movable scroll is assembled to the fixed scroll, the bush is rotated around the eccentric shaft in the rotation direction of the bush in which the distance between the center of the bush and the rotation axis of the rotation shaft decreases. At this time, in order to make the movable-side spiral wall not in contact with the fixed-side spiral wall, the bush is arranged in an eccentric shaft in the rotational direction of the bush in which the distance between the center of the bush and the rotational axis of the rotational shaft decreases. It is only necessary to rotate it slightly around. Therefore, there is a relatively large space between the portion near the rotation direction of the bush, where the distance between the center of the bush and the rotation axis of the rotation shaft on the outer peripheral surface of the balance weight decreases, and the inner peripheral surface of the housing wall. There is.

  Therefore, the balance weight of the present invention has a protruding portion that protrudes radially outward from the first virtual circle at least near the rotation direction of the bush, where the distance between the center of the bush and the rotation axis of the rotation shaft decreases. According to this, compared with the case where the whole outer peripheral surface of a balance weight is extended along the 1st virtual circle centering on the center of a bush, the space between a balance weight and the inner peripheral surface of a storage wall is sufficient. Can be used effectively to increase the balance weight. As a result, the balance weight can easily cancel the centrifugal force acting on the movable scroll when the movable scroll revolves, and the size of the scroll compressor does not increase in size, and the amount of unbalance of the movable scroll can be increased. Can be reduced.

  In the scroll compressor, an outer peripheral surface of the protruding portion extends along a second virtual circle having a diameter larger than that of the first virtual circle, and the center of the second virtual circle is the center of the bush. The distance between the center of the bush and the rotation axis of the rotary shaft is smaller than the center, and is closer to the rotation direction of the bush, and is more radially outward than the first virtual circle at the protruding portion. It is preferable that the amount of protrusion increases as the distance from the center of the bush to the rotation axis of the rotary shaft decreases toward the bush turning direction.

  According to this, the shape of the balance weight can be simplified, and the space between the balance weight and the inner peripheral surface of the containing wall can be efficiently and effectively used to increase the balance weight in a well-balanced manner. Can do.

  According to the present invention, the unbalanced amount of the movable scroll can be reduced without increasing the size of the scroll compressor.

A side sectional view showing a scroll type compressor in an embodiment. FIG. 2A is a cross-sectional view taken along line 2a-2a in FIG. 1, and the bush is rotated around the eccentric shaft in the rotational direction of the bush in which the distance between the center of the bush and the rotational axis of the rotational shaft increases. The longitudinal cross-sectional view which shows a state, (b) is a longitudinal cross-section which shows the state which the bush is rotating around the eccentric shaft in the rotation direction of the bush in which the distance between the center of the bush and the rotation axis of the rotation shaft decreases. Figure. The longitudinal cross-sectional view which shows the bush periphery in another embodiment.

An embodiment embodying a scroll compressor will be described below with reference to FIGS. 1 and 2. The scroll compressor is used for a vehicle air conditioner.
As shown in FIG. 1, the housing 11 of the scroll compressor 10 has a covered cylindrical front housing 13 connected to one end of a bottomed cylindrical center housing 12 (shell). A covered cylindrical rear housing 14 is connected to the end. The center housing 12 is open to the front housing 13 side, and a fixed scroll 15 is integrally formed therein. The fixed scroll 15 includes a disk-shaped fixed side substrate 15 a that forms the bottom wall of the center housing 12, and a fixed side spiral wall 15 b that is erected from the fixed side substrate 15 a toward the front housing 13. .

  A movable scroll 16 is accommodated in the center housing 12. The movable scroll 16 is composed of a movable substrate 16a having a disk shape and a movable spiral wall 16b standing from the movable substrate 16a toward the fixed substrate 15a. The fixed scroll 15 and the movable scroll 16 are disposed to face each other. The fixed-side spiral wall 15b and the movable-side spiral wall 16b are meshed with each other. The distal end surface of the fixed spiral wall 15b is in contact with the movable substrate 16a, and the distal surface of the movable spiral wall 16b is in contact with the fixed substrate 15a. The compression chamber 17 is defined by the fixed substrate 15a and the fixed spiral wall 15b, and the movable substrate 16a and the movable spiral wall 16b.

  A large-diameter portion 18 a of the rotation shaft 18 is rotatably supported on the front housing 13 via a radial bearing 19. A vehicle engine E as an external drive source is operatively connected to the tip of the small diameter portion 18b of the rotating shaft 18 via a power transmission mechanism PT. In the large-diameter portion 18a of the rotary shaft 18, an eccentric shaft 20 that protrudes toward the movable scroll 16 from a position eccentric to the rotary axis L1 of the rotary shaft 18 is integrally formed on the end surface 18c on the movable scroll 16 side. Yes.

  A bush 22 with an integrated balance weight 21 is fitted to the eccentric shaft 20. The balance weight 21 is integrally formed with the bush 22. The balance weight 21 cancels the centrifugal force acting on the movable scroll 16 when the movable scroll 16 revolves, and reduces the unbalance amount of the movable scroll 16. An eccentric hole 22 h is formed in the bush 22 at a position eccentric with respect to the center L <b> 2 of the bush 22. The bush 22 can be rotated (swinged) around the eccentric shaft 20 by fitting the eccentric shaft 20 into the eccentric hole 22h.

  On the end surface 18c of the large-diameter portion 18a of the rotating shaft 18, a circular recess 18d is formed. An insertion pin 22a to be inserted into the recess 18d is projected from the end surface of the bush 22 on the large diameter portion 18a side of the rotary shaft 18. Then, the swing around the eccentric shaft 20 in the bush 22 is restricted by the insertion pin 22a and the recess 18d coming into contact with each other.

  A cylindrical boss portion 16c into which the bush 22 is fitted and inserted via a bearing 23 is formed to protrude from the movable substrate 16a. The movable side substrate 16 a is supported by the bush 22 via the bearing 23 so as to be rotatable relative to the bush 22. The center L2 of the bush 22 is located on the outer side in the radial direction of the rotary shaft 18 with respect to the rotary axis L1 of the rotary shaft 18. The center of the movable side substrate 16 a coincides with the center L 2 of the bush 22, and the distance between the center L 2 of the bush 22 and the rotation axis L 1 of the rotary shaft 18 becomes the revolution radius of the movable scroll 16. Then, when the bush 22 swings around the eccentric shaft 20, the distance between the center L <b> 2 of the bush 22 and the rotation axis L <b> 1 of the rotary shaft 18 changes, and thus the revolution radius of the movable scroll 16 changes. Thus, the eccentric shaft 20, the bush 22 and the bearing 23 constitute a so-called driven crank mechanism 25 that varies the revolution radius of the movable scroll 16. Such a driven crank mechanism 25 is already known.

  The front housing 13 has a cylindrical accommodation wall 13a that accommodates the balance weight 21 therein. The housing wall 13 a has an inner peripheral surface 13 b centering on the rotation axis L <b> 1 of the rotation shaft 18. The housing wall 13a surrounds the boss portion 16c. A rotation prevention mechanism 26 is disposed between the movable side substrate 16a and the accommodation wall 13a (front housing 13). The rotation prevention mechanism 26 includes a plurality of (in the present embodiment, six) circular recesses 27 provided on the outer peripheral portion of the end surface of the movable side substrate 16a opposite to the movable spiral wall 16b, and the accommodation wall 13a. It comprises a pin 28 protruding from the outer peripheral portion of the end face on the side facing the movable substrate 16a, and a ring member 29 fitted in each recess 27. A pin 28 is inserted into each ring member 29.

  A suction chamber 30 is defined between the outer peripheral wall of the center housing 12 and the outermost peripheral part of the movable spiral wall 16b. A suction port 31 communicating with the suction chamber 30 is formed on the outer peripheral wall of the center housing 12. A discharge port 32 is formed in the fixed side substrate 15 a and the discharge port 32 communicates with the compression chamber 17. The discharge port 32 is opened and closed by a discharge valve 33 fixed to the fixed side substrate 15a. The opening degree of the discharge valve 33 is regulated by a retainer 34 fixed to the fixed side substrate 15a. The discharge port 32 communicates with a discharge chamber 35 defined by the center housing 12 and the rear housing 14. A discharge port 36 communicating with the discharge chamber 35 is formed in the rear housing 14. The discharge port 36 and the suction port 31 are communicated with each other by an external refrigerant circuit (not shown).

  As shown in FIGS. 2A and 2B, the balance weight 21 has a rotational direction of the bush 22 in which the distance between the center L2 of the bush 22 and the rotational axis L1 of the rotational shaft 18 decreases (FIG. 2A). And in the direction of the arrow R1 shown in (b), a protruding portion 21a that protrudes radially outward from the first virtual circle C1 centered on the center L2 of the bush 22 is provided. The outer peripheral surface 21b of the protruding portion 21a is the outer peripheral surface of the balance weight 21 and has a semicircular arc shape extending along the second virtual circle C2 having a larger diameter than the first virtual circle C1. The center P2 of the second virtual circle C2 is located closer to the rotation direction of the bush 22 where the distance between the center L2 of the bush 22 and the rotation axis L1 of the rotation shaft 18 is smaller than the center L2 of the bush 22.

  The balance weight 21 is located in the rotation direction of the bush 22 (the direction of the arrow R2 shown in FIGS. 2A and 2B) in which the distance between the center L2 of the bush 22 and the rotation axis L1 of the rotation shaft 18 increases. It has the 1st end edge 21c. Further, the balance weight 21 has a second end edge 21d positioned in the rotation direction of the bush 22 in which the distance between the center L2 of the bush 22 and the rotation axis L1 of the rotation shaft 18 decreases. The first end edge 21c, the second end edge 21d, the center of the first imaginary circle C1 (center L2 of the bush 22) and the center P2 of the second imaginary circle C2 are arranged on the same straight line. The first edge 21c is located on the first virtual circle C1 and the second virtual circle C2. That is, the first virtual circle C1 and the second virtual circle C2 are in a positional relationship inscribed in each other. The amount of protrusion of the protruding portion 21a radially outward from the first imaginary circle C1 is closer to the rotational direction of the bush 22 where the distance between the center L2 of the bush 22 and the rotational axis L1 of the rotating shaft 18 decreases. As it increases.

Next, the operation of this embodiment will be described.
By the way, the movable scroll 16 and the fixed scroll 15 have minute processing errors and assembly errors, so that a backlash (gap) is provided in advance between the movable spiral wall 16b and the fixed spiral wall 15b.

  As shown in FIG. 2A, when the driving force of the engine E is transmitted to the rotary shaft 18 via the power transmission mechanism PT and the rotary shaft 18 rotates in the forward direction, the bush 22 acts on the movable scroll 16. Swing around the eccentric shaft 20 based on the compression reaction force. When the bush 22 swings around the eccentric shaft 20, the distance between the center L <b> 2 of the bush 22 and the rotation axis L <b> 1 of the rotary shaft 18 increases, and the revolution radius of the movable scroll 16 increases. When the movable spiral wall 16b comes into contact with the fixed spiral wall 15b, the swing around the eccentric shaft 20 in the bush 22 is restricted, and the revolution radius of the movable scroll 16 is fixed.

  Further, the rotation of the rotary shaft 18 is transmitted to the movable scroll 16 via the eccentric shaft 20, the bush 22 and the bearing 23, and the movable scroll 16 rotates in the forward direction. When the movable spiral wall 16b comes into contact with the fixed spiral wall 15b, the pin 28 and the ring member 29 come into contact with each other, the rotation of the movable scroll 16 is prevented, and the movable scroll 16 revolves in the forward direction. Only allowed. As a result, the movable scroll 16 revolves in the forward direction while the movable spiral wall 16b is in contact with the fixed spiral wall 15b. Therefore, leakage of the refrigerant from the compression chamber 17 is suppressed, and the volume of the compression chamber 17 is reduced to compress the refrigerant.

  As shown in FIG. 2 (b), when the movable scroll 16 is assembled to the fixed scroll 15, the bush 22 is moved in the direction opposite to that when the rotary shaft 18 is rotating in the forward direction. Swing around. Then, the distance between the center L2 of the bush 22 and the rotation axis L1 of the rotary shaft 18 decreases, and the revolution radius of the movable scroll 16 decreases. As a result, the relative position of the movable spiral wall 16b with respect to the fixed spiral wall 15b becomes a position where the movable spiral wall 16b does not contact the fixed spiral wall 15b, and the movable scroll 16 can be easily moved with respect to the fixed scroll 15. It can be assembled.

  When the bushing 22 swings around the eccentric shaft 20 in the direction opposite to that when the rotary shaft 18 rotates in the forward direction, when the insertion pin 22a comes into contact with the recess 18d, The swing radius of the movable scroll 16 is fixed. As a result, when the bush 22 swings around the eccentric shaft 20 in the direction opposite to that when the rotating shaft 18 rotates in the forward direction, the center L2 of the bush 22 and the rotating axis L1 of the rotating shaft 18 Until the distance increases, the bush 22 is restricted from swinging around the eccentric shaft 20. When the bush 22 swings around the eccentric shaft 20 in a direction opposite to the direction in which the rotation shaft 18 rotates in the forward direction, the distance between the center L2 of the bush 22 and the rotation axis L1 of the rotation shaft 18 is When the shortest distance is reached, the insertion pin 22a comes into contact with the recess 18d, and the swing around the eccentric shaft 20 in the bush 22 is restricted. FIG. 2B shows a state where the distance between the center L2 of the bush 22 and the rotation axis L1 of the rotation shaft 18 is the shortest distance.

  For example, consider the case where the entire outer peripheral surface of the balance weight 21 passes on the first virtual circle C1 centered on the center L2 of the bush 22. In order to suppress the leakage of the refrigerant from the compression chamber 17, it is preferable to bring the movable side spiral wall 16b into contact with the fixed side spiral wall 15b. Therefore, the bush 22 has an eccentric shaft in the rotational direction of the bush 22 in which the distance between the center L2 of the bush 22 and the rotational axis L1 of the rotary shaft 18 increases until the movable spiral wall 16b contacts the fixed spiral wall 15b. Rotate around 20. Then, the gap between the portion near the rotation direction of the bush where the distance between the center L2 of the bush 22 and the rotation axis L1 of the rotary shaft 18 increases on the outer peripheral surface of the balance weight 21 and the inner peripheral surface 13b of the housing wall 13a. It gets smaller.

  On the other hand, in order to assemble the movable scroll 16 to the fixed scroll 15, the movable side spiral wall 16b needs to be in a position that does not contact the fixed side spiral wall 15b. Therefore, when the movable scroll 16 is assembled to the fixed scroll 15, the bush 22 is eccentrically placed in the rotational direction of the bush 22 in which the distance between the center L 2 of the bush 22 and the rotational axis L 1 of the rotational shaft 18 decreases. Rotate around. At this time, in order to place the movable-side spiral wall 16b in a position not in contact with the fixed-side spiral wall 15b, the bush 22 is a bush in which the distance between the center L2 of the bush 22 and the rotation axis L1 of the rotary shaft 18 is reduced. Only a slight rotation around the eccentric shaft 20 in the 22 rotation directions is required. Therefore, between the portion of the outer peripheral surface of the balance weight 21 near the rotational direction of the bush 22 where the distance between the center L2 of the bush 22 and the rotational axis L1 of the rotary shaft 18 decreases, and the inner peripheral surface 13b of the housing wall 13a. Has a relatively large space.

  Therefore, the balance weight 21 having the above configuration protrudes outward in the radial direction from the first virtual circle C1 toward the rotation direction of the bush 22 where the distance between the center L2 of the bush 22 and the rotation axis L1 of the rotation shaft 18 decreases. It has a protruding portion 21a. The amount of protrusion of the protruding portion 21a radially outward from the first imaginary circle C1 is closer to the rotational direction of the bush 22 where the distance between the center L2 of the bush 22 and the rotational axis L1 of the rotating shaft 18 decreases. As it increases. Therefore, compared with the case where the entire outer peripheral surface of the balance weight 21 extends along the first virtual circle C1, the space between the balance weight 21 and the inner peripheral surface 13b of the accommodation wall 13a is effectively used. The physique of the balance weight 21 is increasing. As a result, the balance weight 21 makes it easy to cancel the centrifugal force acting on the movable scroll 16 when the movable scroll 16 revolves, and the unbalance amount of the movable scroll 16 is reduced.

In the above embodiment, the following effects can be obtained.
(1) The balance weight 21 protrudes outward in the radial direction from the first virtual circle C1 toward the rotation direction of the bush 22 where the distance between the center L2 of the bush 22 and the rotation axis L1 of the rotation shaft 18 decreases. 21a. According to this, compared with the case where the entire outer peripheral surface of the balance weight 21 extends along the first virtual circle C1, the space between the balance weight 21 and the inner peripheral surface 13b of the accommodation wall 13a is effectively used. Thus, the physique of the balance weight 21 can be increased. As a result, the balance weight 21 can easily cancel out the centrifugal force acting on the movable scroll 16 when the movable scroll 16 revolves, and the movable scroll 16 does not increase in size, and the movable scroll is not enlarged. The amount of unbalance of 16 can be reduced.

  (2) The outer peripheral surface 21b of the protruding portion 21a extends on the second virtual circle C2 having a larger diameter than the first virtual circle C1. The center P2 of the second virtual circle C2 is located closer to the rotation direction of the bush 22 where the distance between the center L2 of the bush 22 and the rotation axis L1 of the rotation shaft 18 is smaller than the center L2 of the bush 22. The amount of protrusion of the protruding portion 21a radially outward from the first imaginary circle C1 is closer to the rotational direction of the bush 22 where the distance between the center L2 of the bush 22 and the rotational axis L1 of the rotating shaft 18 decreases. As it increases. According to this, the shape of the balance weight 21 can be simplified, and the space between the balance weight 21 and the inner peripheral surface 13b of the accommodating wall 13a can be efficiently and effectively used to increase the size of the balance weight 21. It can be increased in a balanced manner.

  (3) According to this embodiment, in order to increase the physique of the balance weight 21, it is not necessary to secure the accommodation space of the balance weight 21 inside the accommodation wall 13a wider than the existing space. Therefore, the physique of the balance weight 21 can be increased without increasing the physique of the scroll compressor 10.

In addition, you may change the said embodiment as follows.
As shown in FIG. 3, the balance weight 21 is closer to the rotation direction of the bush 22 where the distance between the center L2 of the bush 22 and the rotation axis L1 of the rotation shaft 18 is smaller than the first virtual circle C1. What is necessary is just to have the protrusion part 21A which protrudes to radial direction outer side. In this case, the balance weight 21 has a first outer peripheral surface 211 extending along the first virtual circle C1 and a second outer peripheral surface 212 of the protruding portion 21A. The second outer peripheral surface 212 is continuous with the first outer peripheral surface 211. In short, the shape of the balance weight 21 is not particularly limited.

  In the embodiment, the center of the first imaginary circle C1 (center L2 of the bush 22) and the center P2 of the second imaginary circle C2 are displaced with respect to the straight line connecting the first end edge 21c and the second end edge 21d. It may be arranged at a position.

  In the embodiment, the first edge 21c may not be located on the first virtual circle C1. That is, the first virtual circle C1 and the second virtual circle C2 do not have to be in a positional relationship inscribed in each other.

  In the embodiment, the protruding amount of the protruding portion 21a outward in the radial direction from the first virtual circle C1 is the rotational direction of the bush 22 in which the distance between the center L2 of the bush 22 and the rotational axis L1 of the rotating shaft 18 decreases. You may set so that the amount of protrusion of the protrusion part 21a may decrease gradually, after increasing as it approaches.

  In the embodiment, the balance weight 21 may not be integrally formed with the bush 22, and the balance weight 21, which is a separate member from the bush 22, may be provided integrally with the bush 22.

  In the embodiment, the fixed scroll 15 may not be integrally formed with the center housing 12, and the fixed scroll 15, which is a separate member from the center housing 12, may be fixed inside the center housing 12.

  In the embodiment, the rotary shaft 18 may be rotationally driven by the driving force of the electric motor.

  DESCRIPTION OF SYMBOLS 10 ... Scroll type compressor, 11 ... Housing, 13a ... Housing wall, 13b ... Inner peripheral surface, 15 ... Fixed scroll, 15b ... Fixed side spiral wall, 16 ... Movable scroll, 16b ... Movable side spiral wall, 17 ... Compression chamber , 18 ... rotating shaft, 20 ... eccentric shaft, 21 ... balance weight, 21a, 21A ... protruding portion, 21b ... outer peripheral surface, 22 ... bush.

Claims (2)

A fixed scroll having a fixed spiral wall fixed to the housing, a movable scroll having a movable spiral wall meshing with the fixed spiral wall, and a volume reduction based on a revolving motion of the movable scroll with respect to the fixed scroll. A compression chamber for compressing the refrigerant; a rotating shaft rotatably supported by the housing; an eccentric shaft protruding toward the movable scroll from a position eccentric with respect to a rotation axis of the rotating shaft; and the eccentric shaft A scroll compressor including a bush fitted and rotatable around the eccentric shaft, and a balance weight provided integrally with the bush,
The housing has an inner peripheral surface centering on the rotation axis of the rotation shaft and a receiving wall for receiving the balance weight, and the balance weight includes at least the center of the bush and the rotation axis of the rotation shaft. possess distance in the rotational direction toward the bushing to be decreased, the first protruding portion protruding radially outward from an imaginary circle centered on the center of the bush and,
The outer peripheral surface of the protruding portion extends along a second imaginary circle having a diameter larger than that of the first imaginary circle,
The balance weight has a first end edge located in a rotation direction of the bush in which a distance between a center of the bush and a rotation axis of the rotation shaft increases,
The scroll compressor according to claim 1, wherein the first end edge is located on the first virtual circle and the second virtual circle . Center before Symbol second imaginary circle is also the center of the bush is positioned in the rotational direction toward the bush the distance between the axis of rotation of the center with the rotation axis of the bush is reduced,
The amount of protrusion of the protruding portion outward in the radial direction from the first imaginary circle increases as the distance from the center of the bush to the rotation axis of the rotating shaft decreases toward the rotating direction of the bush. The scroll compressor according to claim 1.