JP2017078361A - Scroll fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure rigidity of joint between a bush and a connection part in a bush assembly.SOLUTION: In a scroll compressor, a bush assembly 37 includes: a bush 41 having a contact end surface 41b which comes in contact with an end surface 19a of a rotary shaft 19 when an eccentric pin 25 is inserted thereinto, the bush 41 configured to be inserted into a cylindrical boss 35c provided on a bottom surface of a revolving scroll 35; a balance weight 43 having a connection part 43A, which is disposed at an outer periphery part of the bush 41 and near the contact end surface 41b, and a weight 43B which protrudes in a direction away from the contact end surface 41b at a part of an outer periphery fo the connection part 43A and is provided in a cantilever manner; a step part 47 provided between the connection part 43A and the contact end surface 41b of the bush 41; and a joint part 49 which is provided at the step part 47 and joins the bush 41 to the connection part 43A.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a scroll fluid machine.

  A scroll compressor, which is a scroll fluid machine, mainly includes a fixed scroll, a turning scroll, a rotating shaft, and a drive unit inside a hermetic housing. Then, the rotating shaft is rotated by the drive unit, and the orbiting scroll to which the rotation is transmitted meshes with the fixed scroll and rotates to compress the fluid.

  Conventionally, for example, Patent Document 1 discloses a slide bush that adjusts the revolution radius of a orbiting scroll according to a spiral shape in a scroll fluid machine. Each of the spiral wraps of the orbiting scroll and the fixed scroll is designed based on a predetermined optimum revolution radius, but if a gap occurs between the meshing of each lap due to dimensional tolerance, fluid flows from the gap. There is a problem of leakage. The slide bush is inserted into the cylindrical boss in the orbiting scroll, and the bush into which the eccentric pin of the rotary shaft is inserted, the connecting portion connected to the side portion of the bush, and the balance formed integrally with the connecting portion. And weights. The slide bush is configured such that the bush is slidable in the radial direction of the rotary shaft with respect to the eccentric pin. Therefore, the diameter of the slide bush depends on the gas pressure in the scroll compression chamber, the centrifugal force on the orbiting scroll, and the centrifugal force on the balance weight. By sliding in the direction and changing the revolution radius of the boss in which the bush is inserted, the laps of the orbiting scroll and the fixed scroll are brought into contact with each other, thereby preventing the occurrence of a gap between them.

JP 2003-343454 A

  By the way, in recent years, high performance of the scroll fluid machine is demanded, and it is desired to use the rotational speed of the rotary shaft as a higher rotational speed than the current state. However, if the rotational speed of the rotary shaft becomes high, the centrifugal force acts excessively on the balance weight, so the connecting part (balance weight) comes off from the bush or the connecting part (balance weight) There is a risk of displacement. Therefore, it is desired to ensure the rigidity of the joint between the bush and the connecting portion (balance weight).

  The present invention solves the above-described problems, and an object of the present invention is to provide a scroll fluid machine that can ensure the rigidity of joining between a bush and a connecting portion in a bush assembly.

  In order to achieve the above-mentioned object, a scroll fluid machine of the present invention includes a fixed scroll fixed to a housing, a turning scroll provided so as to be able to turn while being engaged with the fixed scroll, and rotatable with respect to the housing. A rotating shaft having an eccentric pin supported by the shaft and having an eccentric pin, and a bushing assembly interposed between the eccentric pin and the orbiting scroll to transmit the rotational movement of the eccentric pin as the orbiting scroll. The bush assembly has a contact end surface that contacts the end surface of the rotating shaft with the eccentric pin inserted therein, and a cylindrical boss provided on the bottom surface of the orbiting scroll. The bush to be inserted and the outer periphery of the bush and arranged near the contact end surface A connecting weight and a balance weight having a weight provided in a cantilevered manner extending in a direction away from the contact end surface on a part of the outer periphery of the connection portion, and between the connection portion and the contact end surface of the bush And a joint portion provided at the step portion and joining the bush and the connecting portion.

  According to this scroll fluid machine, the moment starting from the connecting portion is caused by the centrifugal force of the weight provided in a cantilevered manner in a direction away from the contact end surface on a part of the outer periphery of the connecting portion. This moment acts to bring the connecting portion closer to the bush side at the stepped portion. For this reason, an excessive load is not applied to the joint portion provided in the step portion, and the rigidity of the joint between the bush and the connection portion can be secured, and the connection portion is detached from the bush or connected to the bush. To prevent the position of the shift.

  Moreover, according to this scroll fluid machine, since the joint portion joining the bush and the connecting portion is provided in the stepped portion, the situation where the joint portion protrudes from the contact end surface of the bush that contacts the end surface of the rotating shaft is prevented. In addition, the joint portion does not interfere with the end surface of the rotating shaft, and processing of the joint portion for preventing the interference can be omitted. In addition, the weight is provided so as to protrude from the connecting portion in a cantilevered direction away from the contact end surface, and the step portion is provided with a joining portion between the contact end surface on the opposite side where the weight extends and the connecting portion. The joining portion can be easily provided regardless of the presence of the weight.

  In the scroll fluid machine of the present invention, the bush assembly is characterized in that the joint portion is provided at a plurality of locations in the circumferential direction of the bush.

  According to this scroll fluid machine, when the joint is formed by welding, the joint is provided at a plurality of locations in the circumferential direction of the bush rather than being provided at the entire circumference of the bush. Thermal deformation of the bush and the connecting portion due to welding heat can be suppressed.

  Further, in the scroll fluid machine according to the present invention, the bush assembly is characterized in that the joint portion is evenly arranged in a circumferential direction of the bush.

  According to this scroll fluid machine, when the joint is formed by welding, the joint is evenly arranged in the circumferential direction of the bush, so that even if the bush or the joint is thermally deformed by welding heat, the joint is uniform. And local deformation can be suppressed.

  Further, in the scroll fluid machine of the present invention, the bush assembly is characterized in that a large number of the joint portions are arranged in the vicinity of the weight.

  According to this scroll fluid machine, with the action of the centrifugal force of the weight, the moment starting from the connecting part acts in the vicinity where the weight is provided, so the joints are provided at multiple locations in the circumferential direction of the bush. In such a case, the effect of ensuring the rigidity of the joining between the bush and the connecting portion can be significantly obtained by arranging many joining portions in the vicinity where the weight is provided.

  Further, in the scroll fluid machine of the present invention, the bush assembly is provided with an oil supply groove along a cylindrical extending direction in an outer peripheral portion of the bush, and the joint portion is provided in a radial direction of the oil supply groove. It is characterized by being arranged away from the range.

  According to this scroll fluid machine, the oil supply groove is for supplying lubricating oil, and when the joint is formed by welding, the joint is disposed away from the radial range of the oil supply groove. By being, it can suppress the thermal deformation of the oil supply groove | channel by welding heat, and can supply lubricating oil by an oil supply groove | channel smoothly.

  In the scroll fluid machine according to the present invention, the bush assembly is characterized in that the bush is formed of a sintered material and the balance weight is formed of a cast iron material.

  According to this scroll fluid machine, since the bush is a sliding member connected to the eccentric pin or the orbiting scroll, it is preferably formed of a sintered material having a relatively high hardness. Moreover, since the balance weight has a weight that balances the dynamic unbalance generated by the unbalanced weight accompanying the revolving orbiting motion of the orbiting scroll, the balance weight is preferably formed of a relatively high-density cast iron material.

  In the scroll fluid machine of the present invention, the bush assembly is characterized in that the bush and the connecting portion of the balance weight are fixed by shrink fitting or interference fitting.

  According to this scroll fluid machine, since the bush and the connection portion of the balance weight are fixed by shrinkage fitting or interference fit, the rigidity of the joint between the bush and the connection portion is increased in synergy with the provision of the joint portion. The effect to ensure can be acquired notably.

  Further, in the scroll fluid machine according to the present invention, the bush assembly is provided with a bush side slide surface in contact with a pin side slide surface provided on a side portion of the eccentric pin on an inner peripheral portion of the bush. It is provided so as to be slidable with respect to the eccentric pin, and the joint portion is arranged away from the radial range of the bush side slide surface.

  According to this scroll fluid machine, the bush side slide surface is a portion that supports the sliding movement of the bush assembly, and when the joint portion is formed by welding, the joint portion is removed from the radial range of the bush side slide surface. By being arranged apart, thermal deformation of the bush side slide surface due to welding heat can be suppressed, and the slide movement of the bush assembly can be performed smoothly.

  In the scroll fluid machine according to the present invention, the bush assembly is configured such that the bush is rotatably provided with respect to the eccentric pin and is inserted into a limit hole formed in an end surface of the rotary shaft to restrict a rotation range. A limit pin is provided, and the joint portion is arranged away from a radial range of a portion to which the limit pin is attached.

  According to this scroll fluid machine, when the joint is formed by welding, the joint is disposed away from the radial range of the part to which the limit pin is attached, and the part to which the limit pin is attached by welding heat Therefore, it is possible to suppress a situation in which the attachment of the limit pin is hindered.

  Further, in the scroll fluid machine according to the present invention, the bush assembly is configured such that the bush is rotatably provided with respect to the eccentric pin, and a limit pin fixed to an end surface of the rotating shaft is inserted to restrict a rotation range. A limit hole is provided, and the joint portion is disposed away from a radial range of a portion where the limit hole is formed.

  According to this scroll fluid machine, when the joint portion is formed by welding, the joint portion is arranged away from the radial range of the portion forming the limit hole, so that the limit hole is formed by welding heat. It is possible to suppress the thermal deformation of the part to be performed, and it is possible to suppress the situation where the accuracy of the rotation range regulated by the limit hole is lowered.

  In the scroll fluid machine of the present invention, the maximum rotational speed of the rotary shaft exceeds 145 rps.

  According to this scroll fluid machine, with the above-described configuration, it is possible to secure the rigidity of the joint between the bush and the connecting portion in the bush assembly, so that a scroll fluid machine in which the maximum rotational speed of the rotary shaft exceeds 145 rps is realized. Can do.

  According to the present invention, the rigidity of joining between the bush and the connecting portion in the bush assembly can be ensured.

FIG. 1 is an overall cross-sectional view of a scroll fluid machine according to an embodiment of the present invention. FIG. 2 is a plan view of the rotating shaft in the scroll fluid machine according to the embodiment of the present invention. FIG. 3 is a cross-sectional side view of a combined rotary shaft and bush assembly in a scroll fluid machine according to an embodiment of the present invention. FIG. 4 is a plan view of the bush assembly in the scroll fluid machine according to the embodiment of the present invention. FIG. 5 is a bottom view of the bush assembly in the scroll fluid machine according to the embodiment of the present invention. FIG. 6 is a plan view of a rotary shaft of another example of the scroll fluid machine according to the embodiment of the present invention. FIG. 7 is an overall cross-sectional view of another example of the scroll fluid machine according to the embodiment of the present invention. FIG. 8 is a side cross-sectional view of another example of a scroll fluid machine according to an embodiment of the present invention in which a rotary shaft and a bush assembly are combined. FIG. 9 is a bottom view of another example bush assembly of a scroll fluid machine according to an embodiment of the present invention.

  Embodiments according to the present invention will be described below in detail with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, constituent elements in the following embodiments include those that can be easily replaced by those skilled in the art or those that are substantially the same.

  FIG. 1 is an overall cross-sectional view of the scroll fluid machine according to the present embodiment.

  FIG. 1 shows a scroll compressor 1 that compresses and discharges a sucked fluid as a scroll fluid machine. Moreover, the scroll compressor 1 of this embodiment is interposed in the refrigerant | coolant flow path which circulates a refrigerant | coolant in an air conditioner, a refrigerator, etc.

  As shown in FIG. 1, the scroll compressor 1 includes a motor 5 serving as a driving unit and a scroll compression mechanism 7 driven by the motor 5 inside a housing 3.

  The housing 3 includes a cylindrical housing body 3a that extends vertically, a bottom 3b that closes the lower end of the housing body 3a, and a lid 3c that closes the upper end of the housing body 3a, and is entirely sealed. It is a pressure vessel. The housing main body 3a is provided with a suction pipe 9 for introducing a refrigerant into the housing 3 at a side portion thereof. The lid 3c is provided with a discharge pipe 11 at the top thereof for discharging the refrigerant compressed by the scroll compression mechanism 7. The housing 3 is provided with a discharge cover 13 between the housing main body 3a and the lid 3c, and the interior of the housing 3 includes a low pressure chamber 3A below the discharge cover 13 and a high pressure chamber 3B above the discharge cover 13. It is divided into and. The discharge cover 13 is formed with an opening hole 13a that connects the low pressure chamber 3A and the high pressure chamber 3B, and a discharge reed valve 13b that opens and closes the opening hole 13a. Further, the bottom in the housing 3 is configured as an oil reservoir in which lubricating oil is accumulated.

  The motor 5 includes a stator 15, a rotor 17, and a rotating shaft 19. The stator 15 is fixed to the inner wall surface at substantially the center in the vertical direction of the housing body 3a. The rotor 17 is provided to be rotatable with respect to the stator 15. The rotating shaft 19 is arranged vertically with respect to the rotor 17. The motor 5 rotates the rotor 17 when power is supplied from the outside of the housing 3, and the rotating shaft 19 rotates together with the rotor 17.

  The rotating shaft 19 is provided with an end protruding above and below the rotor 17, and an axial center CE that extends upward and downward with respect to the housing body 3 a by an upper bearing 21 at the upper end and a lower bearing 23 at the lower end. Is supported rotatably. An eccentric pin 25 is formed at the upper end of the rotating shaft 19 and protrudes upward along an eccentric LE that is offset with respect to the axis CE. The scroll compression mechanism 7 is connected to the upper end of the rotary shaft 19 having the eccentric pin 25. The detailed configuration of the eccentric pin 25 will be described later. Further, the rotary shaft 19 and the eccentric pin 25 are formed with an oil supply hole 27 penetrating vertically. Further, the rotary shaft 19 is provided with a lower end reaching an oil reservoir, and an oil supply pump 29 is provided. The oil supply pump 29 feeds the lubricating oil accumulated in the oil reservoir with the rotation of the rotary shaft 19 into the oil supply hole 27 of the rotary shaft 19.

  The upper bearing 21 penetrates the upper end portion of the rotating shaft 19 and supports the rotating shaft 19 rotatably. The upper bearing 21 has a recess 21 a formed on the upper surface thereof so as to surround the upper end of the penetrated rotary shaft 19. The recess 21 a accommodates a bush assembly 37 described later, and stores the lubricating oil fed by the oil supply pump 29 through the oil supply hole 27. The stored lubricating oil is supplied to the scroll compression mechanism 7.

  Further, the upper bearing 21 is formed with a notch 21b in a part of the outer periphery so as to have a gap with the inner wall surface of the housing main body 3a of the housing 3, and an oil drain hole 21c that connects the notch 21b and the recess 21a is formed. ing. A cover plate 31 is provided below the notch 21 b of the upper bearing 21. The cover plate 31 is provided extending in the vertical direction. The cover plate 31 is formed to bend toward the inner wall surface of the housing body 3a so as to cover the periphery of the notch 21b, and is bent so that the lower end gradually approaches the inner wall surface of the housing body 3a. Has been. And the oil drain hole 21c discharges the lubricating oil excessively stored in the recess 21a to the outer periphery of the upper bearing 21 from the notch 21b. The cover plate 31 receives the lubricating oil discharged from the notch 21b and guides it toward the inner wall surface of the housing body 3a. The lubricating oil guided toward the inner wall surface by the cover plate 31 is returned to the oil reservoir at the bottom in the housing 3 along the inner wall surface by the cover plate 31.

  The scroll compression mechanism 7 is disposed in the housing 3 in the low pressure chamber 3A below the discharge cover 13 and above the upper bearing 21, and includes a fixed scroll 33, a turning scroll 35, a bush assembly 37, and the like. It is equipped with.

  In the fixed scroll 33, a spiral fixed side wrap 33 b is formed on the inner surface (the lower surface in FIG. 1) of the fixed side end plate 33 a fixed inside the housing 3. The fixed-side end plate 33a has a discharge hole 33c formed at the center thereof.

  The orbiting scroll 35 is formed with a spiral movable side wrap 35b on the inner surface (upper surface in FIG. 1) of the movable side end plate 35a facing the inner surface of the fixed side end plate 33a of the fixed scroll 33. Then, the movable side wrap 35b of the orbiting scroll 35 and the fixed side wrap 33b of the fixed scroll 33 are engaged with each other with the phases shifted from each other, so that the compression is defined by the end plates 33a and 35a and the wraps 33b and 35b. A chamber is formed. The orbiting scroll 35 has a cylindrical boss 35c to which the eccentric pin 25 of the rotary shaft 19 is connected to the outer surface (the lower surface in FIG. 1) of the movable side end plate 35a and the eccentric rotation of the eccentric pin 25 is transmitted. Is formed. Further, the orbiting scroll 35 is prevented from rotating based on the eccentric rotation of the eccentric pin 25 by a rotation prevention mechanism 39 such as a well-known Oldham link arranged between the outer surface of the movable side end plate 35a and the upper bearing 21. While turning around.

  The bush assembly 37 is accommodated in the concave portion 21 a of the upper bearing 21 described above, and is interposed between the eccentric pin 25 of the rotary shaft 19 and the boss 35 c of the orbiting scroll 35, and controls the rotational movement of the eccentric pin 25 of the orbiting scroll 35. It is transmitted as a swivel movement. Further, the bush assembly 37 is provided so as to be slidable in the radial direction of the eccentric pin 25 in order to maintain the meshing between the movable side wrap 35 b of the orbiting scroll 35 and the fixed side wrap 33 b of the fixed scroll 33. The detailed configuration of the bush assembly 37 will be described later.

  In the scroll compression mechanism 7, the low-pressure refrigerant introduced into the low-pressure chamber 3 </ b> A in the housing 3 through the suction pipe 9 is compressed between the fixed scroll 33 and the orbiting scroll 35 by the orbiting scroll 35 revolving. It is compressed while inhaling indoors. The compressed high-pressure refrigerant is discharged from the discharge hole 33c of the fixed scroll 33 to the outer surface side of the fixed-side end plate 33a, opens the discharge reed valve 13b of the discharge cover 13 by its own pressure, and opens from the opening hole 13a to the high-pressure chamber. 3B and discharged to the outside of the housing 3 through the discharge pipe 11.

  FIG. 2 is a plan view of a rotating shaft in the scroll fluid machine according to the present embodiment. FIG. 3 is a cross-sectional side view in which the rotary shaft and the bush assembly are combined in the scroll fluid machine according to the present embodiment.

  As shown in FIG. 2, the rotating shaft 19 is formed with an eccentric pin 25 having an eccentric LE that is eccentric with respect to the axis CE as described above. The eccentric pin 25 is formed to protrude upward from the upper end surface 19 a of the rotary shaft 19. The eccentric pin 25 is mainly composed of a first arc 25a, a second arc 25b, and a pin-side slide surface 25c whose outer shape is projected in the extending direction of the axis CE (or the eccentric LE). Yes.

  The first arc 25a is in the range of P1-P2 in FIG. 2 and is rotated by a first radius Ra centering on the position of the eccentric LE with a length exceeding a part of the outer edge 19b of the outer shape of the rotary shaft 19. It is formed within the range of the outer shape of the shaft 19.

  The second arc 25b is in the range of P2-P3 in FIG. 2 and is equal to or less than the radius R forming the outer edge 19b of the rotating shaft 19 in a portion where the first radius Ra exceeds the outer edge 19b of the outer shape of the rotating shaft 19. The length is formed by a second radius Rb centered on the position of the axis CE.

  That is, in the scroll compressor 1 of the present embodiment, the eccentric pin 25 of the rotary shaft 19 has a first outer shape whose length exceeds the part of the outer edge 19b of the rotary shaft 19 and centered on the position of the eccentric LE. The first arc 25a formed within the range of the outer shape of the rotary shaft 19 by the radius Ra, and the position of the axis CE with a length equal to or less than the radius R forming the outer edge 19b in a portion where the first radius Ra exceeds the outer edge 19b. And a second arc 25b formed by a second radius Rb as a center.

  According to the scroll compressor 1, the outer shape of the eccentric shaft 25 is longer than a part of the outer edge 19 b of the rotating shaft 19 and the outer shape of the rotating shaft 19 by the first radius Ra centering on the position of the eccentric LE. By having the first arc 25a formed within the range, a large diameter that can exceed a part of the outer edge 19b of the rotating shaft 19 can be obtained, and the rigidity of the eccentric pin 25 can be improved. As a result, the occurrence of deflection of the eccentric pin 25 can be suppressed.

  Moreover, the outer shape of the eccentric pin 25 is formed by a second radius Rb having a length equal to or less than the radius R forming the outer edge 19b at a portion where the first radius Ra exceeds the outer edge 19b and centering on the position of the axis CE. By having the two circular arcs 25 b, the outer shape of the eccentric pin 25 is prevented from protruding from the outer edge 19 b of the rotating shaft 19. When the outer shape of the eccentric pin 25 protrudes from the outer edge 19b of the rotary shaft 19, the eccentric pin 25 interferes with the processing of the rotary shaft 19, and the processing takes time. When the rotary shaft 19 is inserted into the bearings 21 and 23, However, the eccentric pin 25 is in the way, and it takes time to assemble, but such inconvenience can be eliminated.

In the scroll compressor 1 of the present embodiment, the first radius Ra, the second radius Rb, the radius R, and the distance ρ between the position of the axis CE and the position of the eccentric LE are (Ra ² + ρ ^2). ) It is preferable to satisfy the relationship of ^1/2 ≦ Rb ≦ R.

The second arc 25b is formed by a second radius Rb having a length equal to or less than the radius R forming the outer edge 19b of the rotary shaft 19 and centering on the position of the axis CE, but if the second radius Rb is less than or equal to the radius R, The outer shape of the eccentric pin 25 is reduced in diameter. According to the scroll compressor 1, by setting the lower limit of the second radius Rb according to the relationship of (Ra ² + ρ ² ) ^1/2 ≦ Rb ≦ R, the outer shape of the eccentric pin 25 prevents the diameter reduction. Can do. As a result, the rigidity of the eccentric pin 25 can be improved, and the effect of suppressing the deflection of the eccentric pin 25 can be significantly obtained.

  FIG. 4 is a plan view of the bush assembly in the scroll fluid machine according to the present embodiment.

  As shown in FIGS. 3 and 4, the bush assembly 37 includes a bush 41 and a balance weight 43.

  As shown in FIGS. 3 and 4, the bush 41 has an eccentric pin 25 inserted into a hole 41 a formed in a cylindrical shape. The bush 41 has a contact end surface 41b that contacts the upper end surface 19a of the rotary shaft 19 by inserting the eccentric pin 25 into the hole 41a. The bush 41 is inserted into the boss 35c of the orbiting scroll 35 as shown in FIG. For this reason, the bush 41 is formed in a circular shape in accordance with the cylindrical shape of the boss 35c. A cylindrical orbiting bearing 45 is interposed between the outer peripheral surface of the bush 41 and the inner peripheral surface of the boss 35 c in order to smoothly transmit the eccentric rotation of the bush 41 to the revolution rotation of the orbiting scroll 35.

  Further, the bush 41 is provided with a bush side slide surface 41c facing the pin side slide surface 25c of the eccentric pin 25 in the inner shape of the hole 41a. The bush 41 is formed to have a larger diameter in the inner shape of the hole 41a than the outer shape of the eccentric pin 25 in a direction along the radial direction of the eccentric LE on the pin-side slide surface 25c. For this reason, the bush 41 has a larger diameter than the outer shape of the eccentric pin 25, and the bush side slide surface 41c slides with respect to the pin side slide surface 25c. It is provided so that sliding movement is possible along.

  The balance weight 43 includes a connecting portion 43A and a weight 43B.

  The connecting portion 43 </ b> A is formed in a ring shape, and the hole 43 </ b> Aa is joined to the outer peripheral portion of the bush 41. As described above, since the bush 41 is inserted into the boss 35c of the orbiting scroll 35, the connecting portion 43A is located at a position near the rotary shaft 19 (contact end surface 41b) in order to prevent interference with the boss 35c of the orbiting scroll 35. It is joined to the bush 41.

  The weight 43B is provided in a cantilever manner so as to protrude in a direction away from the contact end surface 41b of the bush 41 (upward in FIG. 3) on a part of the outer periphery of the connecting portion 43A. As shown in FIGS. 3 and 4, the weight 43 </ b> B is opposite to the direction in which the eccentric pin 25 is biased with respect to the rotating shaft 19 in a state where the bush assembly 37 is inserted and attached to the eccentric pin 25 of the rotating shaft 19. Arranged in the direction. The weight 43B is positioned when the bush-side slide surface 41c of the hole 41a in the bush 41 faces the pin-side slide surface 25c of the eccentric pin 25. That is, the bush assembly 37 is slidable with respect to the eccentric pin 25, but is attached in a state in which the rotation is prevented.

  Further, as described above, since the bush 41 is inserted into the boss 35c of the orbiting scroll 35, the weight 43B is disposed at an interval through which the boss 35c (and the orbiting bearing 45) can be inserted. And, it is arranged in an arc shape (or fan shape) along the outer shape of the bush 41.

  The bush assembly 37 configured as described above transmits the rotational movement of the eccentric pin 25 as the rotational movement of the orbiting scroll 35. At this time, the bush assembly 37 is opposite to the deviation of the eccentric pin 25 with respect to the axis CE. The weight 43 </ b> B disposed on the rotary shaft 25 rotates together with the eccentric pin 25, so that the rotation generated by the unbalanced weight of the orbiting scroll 35, the boss 35 c, the orbiting bearing 45, the bush assembly 37, etc. The mechanical imbalance is balanced by the centrifugal force acting on the weight 43B. Moreover, the bush assembly 37 is slidable with respect to the eccentric pin 25, so that the revolution radius of the boss 35c into which the bush 41 is inserted is changed (that is, the orbiting scroll 35 is slid), and the fixed scroll 33 is moved. The revolving orbiting radius of the orbiting scroll 35 is adjusted so as to eliminate the gap due to the dimensional tolerance between the fixed side wrap 33b and the movable side wrap 35b of the orbiting scroll 35, and the laps 33b and 35b are brought into contact with each other. The generation of gaps is suppressed and fluid leakage from the gaps is prevented.

  Here, in the bush assembly 37, a moment acts in a direction away from the bush 41 together with the balance weight 43 from the connecting portion 43A by a centrifugal force acting on the weight 43B. Since this moment acts on the joint portion between the bush 41 and the connecting portion 43 </ b> A, there is a problem that the connecting portion 43 </ b> A is detached from the bush 41 or the position of the connecting portion 43 </ b> A is displaced with respect to the bush 41.

  Therefore, in the present embodiment, in the bush assembly 37, the connection between the bush 41 and the balance weight 43 is devised.

  As shown in FIG. 3, in the scroll compressor 1 of the present embodiment, the connecting portion 43 </ b> A is disposed so as to be shifted in the length direction of the bush 41 (upward in FIG. 3) with respect to the bush 41. A stepped portion 47 is formed between the contact end surface 41b of the bush 41, which is a surface facing the end surface 19a, and the lower surface 43Ab of the connecting portion 43A. The step portion 47 is formed by attaching the connecting portion 43A to the bush 41 so that the lower surface 43Ab of the connecting portion 43A is slightly separated from the upper end surface 19a of the rotating shaft 19 rather than the contact end surface 41b of the bush 41. The step portion 47 is provided with a joint portion 49 that joins the bush 41 and the connecting portion 43A. The joint portion 49 is formed on the lower surface 43Ab of the connecting portion 43A and the side surface of the bush 41 at the step portion 47, and is formed so as not to protrude from the contact end surface 41b of the bush 41 toward the upper end surface 19a of the rotary shaft 19. . The joint portion 49 is formed by laser welding. Note that the joint portion 49 is not limited to laser welding, and may be formed by other welding.

  As described above, in the scroll compressor 1 of the present embodiment, the bush assembly 37 has the contact end surface 41 b into which the eccentric pin 25 is inserted and contacts the end surface 19 a of the rotary shaft 19, and is provided on the bottom surface of the orbiting scroll 35. A bush 41 to be inserted into the cylindrical boss 35c, a connecting portion 43A disposed on the outer periphery of the bush 41 in the vicinity of the contact end surface 41b, and a part of the outer periphery of the connecting portion 43A from the contact end surface 41b. A balance weight 43 having a weight 43B provided in a cantilever manner projecting away from the distance, a stepped portion 47 provided between the connecting portion 43A and the contact end surface 41b of the bush 41, and a bush provided in the stepped portion 47. 41 and the joining part 49 which joined 43 A of connection parts are provided.

  According to the scroll compressor 1, the connecting portion 43A starts from the centrifugal force of the weight 43B provided in a cantilevered manner in a direction away from the contact end face 41b on a part of the outer periphery of the connecting portion 43A. The moment acts to rotate the weight 43B in the direction in which the contact end face 41b is present, but this moment acts to bring the connecting portion 43A closer to the bush 41 in the stepped portion 47. For this reason, an excessive load is not applied to the joint portion 49 provided in the stepped portion 47, the rigidity of the joint between the bush 41 and the connecting portion 43A can be ensured, the connecting portion 43A can be detached from the bush 41, This prevents a situation where the position of the connecting portion 43 </ b> A shifts with respect to the bush 41.

  In addition, since the joint portion 49 that joins the bush 41 and the connecting portion 43A is provided in the stepped portion 47, the situation where the joint portion 49 protrudes to the contact end surface 41b of the bush 41 that contacts the end surface 19a of the rotary shaft 19 occurs. It is possible to prevent the joint 49 from interfering with the end surface 19a of the rotary shaft 19, and the processing of the joint 49 to prevent the interference can be omitted. Further, the weight 43B is provided so as to protrude from the connecting portion 43A in a cantilevered direction in a direction away from the contact end surface 41b, and the step portion 47 is joined between the contact end surface 41b on the opposite side where the weight 43B extends and the connecting portion 43A. Since the portion 49 is provided, the joint portion 49 can be easily provided regardless of the presence of the weight 43B.

  FIG. 5 is a bottom view of the bush assembly in the scroll fluid machine according to the present embodiment.

  Further, in the scroll compressor 1 of the present embodiment, the bush assembly 37 may be provided with the joint portion 49 on the entire circumference in the circumferential direction of the bush 41, but as shown in FIG. It is preferable that the bush 41 is provided at a plurality of locations (three locations in FIG. 5) in the circumferential direction. Note that the circumferential direction of the bush 41 refers to a circumferential direction based on the position of the eccentric LE of the eccentric pin 25.

  According to the scroll compressor 1, when the joint portion 49 is formed by welding, the joint portion 49 is provided at a plurality of locations in the circumferential direction of the bush 41 rather than provided at the entire circumference of the bush 41. It is possible to suppress thermal deformation of the bush 41 and the connecting portion 43A due to welding heat.

  Further, in the scroll compressor 1 according to the present embodiment, the bush assembly 37 has the joint portions 49 arranged evenly in the circumferential direction of the bush 41 when the joint portions 49 are provided at a plurality of locations in the circumferential direction of the bush 41. It is preferable that In FIG. 5, the joint portions 49 are provided at three locations in the circumferential direction of the bush 41, and are evenly arranged every 120 ° with respect to the eccentric LE of the eccentric pin 25.

  According to the scroll compressor 1, when the joint portion 49 is formed by welding, the joint portion 49 is evenly arranged in the circumferential direction of the bush 41, so that the heat of the bush 41 and the connecting portion 43A due to welding heat. Even if deformation occurs, it can be equalized and local deformation can be suppressed.

  Further, in the scroll compressor 1 of the present embodiment, the bush assembly 37 has the joint portion 49 provided in a plurality of locations in the circumferential direction of the bush 41, and the joint portion 49 is provided in the vicinity where the weight 43B is provided. It is preferable that many are arranged. In addition, when the junction part 49 is equally arrange | positioned in the circumferential direction of the bush 41, as shown in FIG. 5, in the structure by which the junction part 49 is provided in the odd number place of the circumferential direction of the bush 41, the junction part 49 is provided. However, many are arranged in the vicinity where the weight 43B is provided.

  According to the scroll compressor 1, the moment from the connecting portion 43 </ b> A acts in the vicinity where the weight 43 </ b> B is provided with the action of the centrifugal force of the weight 43 </ b> B. When provided at a plurality of locations in the direction, the effect of ensuring the rigidity of the joining between the bush 41 and the connecting portion 43A is remarkably obtained by arranging many joining portions 49 in the vicinity where the weight 43B is provided. be able to.

  In the scroll compressor 1 of the present embodiment, as shown in FIGS. 4 and 5, the bush assembly 37 is provided with an oil supply groove 51 on the outer peripheral portion of the bush 41 along the cylindrical extending direction. It is preferable that the joint portion 49 is disposed away from the radial range of the oil supply groove 51.

  According to this scroll compressor 1, the oil supply groove 51 is for supplying lubricating oil to the scroll compression mechanism 7, and when the joint portion 49 is formed by welding, the joint portion 49 is not connected to the oil supply groove 51. By being arranged away from the radial range, thermal deformation of the oil supply groove 51 due to welding heat can be suppressed, and supply of lubricating oil through the oil supply groove 51 can be performed smoothly.

  Moreover, in the scroll compressor 1 of this embodiment, it is preferable that the bush assembly 37 has the bush 41 formed of a sintered material and the balance weight 43 formed of a cast iron material.

  According to the scroll compressor 1, since the bush 41 is a sliding member connected to the eccentric pin 25 and the boss 35c of the orbiting scroll 35, it is preferable that the bush 41 is formed of a relatively high hardness sintered material. Further, the balance weight 43 has a weight 43B that balances dynamic unbalance generated by the unbalanced weight of the orbiting scroll 35, the boss 35c, the orbiting bearing 45, the bush assembly 37, and the like with the revolution orbiting motion of the orbiting scroll 35. For this reason, it is preferably formed of a relatively high-density cast iron material.

  Moreover, in the scroll compressor 1 of this embodiment, it is preferable that the bush assembly 37 fixes the bush 41 and the connection part 43A of the balance weight 43 by shrink fitting or interference fitting.

  According to the scroll compressor 1, the bush 41 and the connecting portion 43 </ b> A of the balance weight 43 are fixed by shrink fitting or interference fitting, so that the bush 41 and the connecting portion are combined with the joint portion 49. The effect of ensuring the rigidity of joining with 43A can be remarkably obtained. Note that when the bush 41 and the connecting portion 43A are joined (when the joining portion 49 is provided), the inner diameter of the hole 43Aa of the connecting portion 43A is made smaller than the outer diameter of the bush 41, and shrink fitting or interference fitting is performed. Thus, the bush 41 and the connecting portion 43A are fitted together, and then the joint portion 49 is formed by welding. In this manner, the bushing 41 and the connecting portion 43A are fitted in advance by shrink fitting or interference fitting, so that the joint portion 49 can be formed by welding without causing a deviation between the bush 41 and the connecting portion 43A. .

  Moreover, in the scroll compressor 1 of this embodiment, when the joint part 49 is provided in the several location of the circumferential direction of the bush 41, as shown in FIG. It is preferable that the side slide surface 41c is disposed away from the radial range.

  According to the scroll compressor 1, the bush side slide surface 41 c is a portion that supports the sliding movement of the bush assembly 37. When the joint portion 49 is formed by welding, the joint portion 49 becomes the bush side slide surface 41 c. Since the thermal deformation of the bush side slide surface 41c due to welding heat can be suppressed, the slide movement of the bush assembly 37 can be performed smoothly.

  Moreover, in the scroll compressor 1 of this embodiment, the maximum rotation speed of the rotating shaft 19 exceeds 145 rps.

  According to the scroll compressor 1, the occurrence of deflection of the eccentric pin 25 can be suppressed by the above-described configuration, and the rigidity of the joint between the bush 41 and the connecting portion 43 </ b> A in the bush assembly 37 can be ensured. Therefore, the scroll compressor 1 in which the maximum rotational speed of the rotary shaft 19 exceeds 145 rps can be realized.

  Here, FIG. 7 is an overall cross-sectional view of another example of the scroll fluid machine according to the present embodiment. FIG. 8 is a side cross-sectional view in which another example of the scroll fluid machine according to the present embodiment is combined with a rotating shaft and a bush assembly. FIG. 9 is a bottom view of a bush assembly of another example of the scroll fluid machine according to the present embodiment.

  FIG. 7 shows a scroll compressor 101 that compresses and discharges a sucked fluid as a scroll fluid machine. The scroll compressor 101 is interposed in a refrigerant flow path that circulates a refrigerant in an air conditioner, a refrigerator, or the like, and is used particularly in a vehicle air conditioner.

  As shown in FIG. 7, the scroll compressor 101 includes a housing 103, an inverter motor 105, a fixed scroll 133 and a orbiting scroll 135 that compress refrigerant, a rotating shaft 119 that drives the orbiting scroll 135, and a bush assembly 137. , Is provided. As shown in FIG. 8, the fixed scroll 133, the orbiting scroll 135, and the bush assembly 137 constitute a scroll compression mechanism 107 that is driven by the inverter motor 105.

  The housing 103 is a housing that houses the fixed scroll 133, the orbiting scroll 135, the rotating shaft 119, the inverter motor 105, and the like, and includes a first housing 103a, a second housing 103b, a motor case 103c, Is provided.

  The first housing 103a is a member formed in a bottomed cylindrical shape, and a fixed scroll 133 is fixed to the bottom surface. A discharge chamber 103A into which the refrigerant compressed by the fixed scroll 133 and the orbiting scroll 135 flows is formed between the fixed scroll 133 and the first housing 103a.

  The first housing 103a is provided with a discharge portion (not shown) for guiding the refrigerant in the discharge chamber 103A to the outside, and a first flange portion 103aa. The first flange portion 103aa is used when the first housing 103a, the second housing 103b, and the motor case 103c are integrally fixed using the housing bolt 104, and is an end portion on the opening side of the first housing 103a. And a member extending radially outward.

  As shown in FIG. 7, the second housing 103b is a member provided with a first bearing 121 formed in a cylindrical shape and a flange 103ba extending radially outward from the end on the first housing 103a side. is there. The second housing 103b is disposed so that the flange 103ba is sandwiched between the first housing 103a and the motor case 103c.

  In the second housing 103b, a radial bearing 122 that rotatably supports the rotary shaft 119 is provided in the first bearing 121. The first bearing 121 is provided with a suction passage 124 extending along the axis CE of the rotary shaft 119 in the wall surface. Further, the second housing 103b is provided with a second flange portion 103bb that is used when the first housing 103a, the second housing 103b, and the motor case 103c are integrally fixed using the housing bolt 104 on the flange portion 103ba. Yes. The second flange portion 103bb is a member that extends radially outward from the flange portion 103ba.

  As shown in FIG. 7, the motor case 103c is a member formed in a bottomed cylindrical shape, and a stator 115 of the inverter motor 105 is fixed therein. The motor case 103c is provided with a suction portion (not shown) through which refrigerant flows from the outside, a box 103ca, and a case flange portion 103cb.

  The box 103ca opens toward the outside in the radial direction of the motor case 103c, and the inverter portion 179 of the inverter motor 105 is accommodated therein. The case flange portion 103cb is used when the first housing 103a, the second housing 103b, and the motor case 103c are integrally fixed using the housing bolt 104, and has a radius from the end of the motor case 103c on the opening side. This is a member extending outward in the direction.

  The inverter motor 105 is a motor that is rotationally driven by a frequency-controlled alternating current, and is an electric part that drives the orbiting scroll 135 to revolve. As shown in FIG. 7, the inverter motor 105 includes a rotor 117 and a stator 115 that revolve the orbiting scroll 135 via a rotating shaft 119 and a bush assembly 137, and an inverter unit 179 that controls an alternating current supplied to the stator 115. , Is provided.

  The rotor 117 generates a rotational driving force by an alternating magnetic field formed by the stator 115, and is a permanent magnet formed in a cylindrical shape. The rotor 117 has a rotating shaft 119 fixed thereto. The stator 115 forms an alternating magnetic field based on the alternating current supplied from the inverter unit 179 and rotates the rotor 117. The stator 115 is fixed to the inner peripheral surface of the motor case 103c using a fixing method such as shrink fitting.

  The inverter unit 179 controls an alternating current supplied to the stator 115, and is disposed in the box 103ca. The inverter unit 179 is provided with a capacitor 181, a plurality of substrates 185 including electronic elements such as a power transistor 183, and a terminal 187.

  The capacitor 181 temporarily stores current. Electronic elements such as the power transistor 183 provided on the substrate 185 are for controlling the frequency of the alternating current supplied from the outside. The terminal 187 supplies an alternating current to the stator 115. The substrate 185 provided with the power transistor 183 is fixed in contact with the motor case 103c in the box 103ca, and is configured to release heat generated from the power transistor 183 to the motor case 103c. The other substrate 185 is fixed at a position away from the motor case 103c. In other words, the substrate 185 is fixed in a stacked state. The terminal 187 supplies an alternating current controlled by the power transistor 183 and the like to the stator 115.

  As described above, the inverter motor 105 may be used as the electric part, and other known motors may be used as the electric part, and there is no particular limitation.

  As shown in FIG. 7, the fixed scroll 133 and the orbiting scroll 135 form a closed compression chamber C to compress the refrigerant. The fixed scroll 133 is provided with a fixed side end plate 133 a and a spiral fixed side wrap 133 b extending from the fixed side end plate 133 a toward the orbiting scroll 135. The fixed scroll 133 is fixed to the bottom surface of the first housing 103a. The fixed end plate 133a is provided with a discharge hole 133c at the center thereof. The refrigerant compressed in the compression chamber C is discharged into the discharge chamber 103A through the discharge hole 133c.

  On the other hand, the orbiting scroll 135 is provided with a movable side end plate 135 a and a spiral movable side wrap 135 b extending from the movable side end plate 135 a toward the fixed scroll 133. The orbiting scroll 135 is supported by the rotary shaft 119 and the rotation preventing portion 139 so as to be able to revolve. The orbiting scroll 135 is provided with a cylindrical boss 135c extending toward the rotating shaft 119 on a surface (also referred to as a bottom surface) facing the rotating shaft 119 of the movable side end plate 135a. The revolving driving force by the rotating shaft 119 is transmitted to the boss 135c via the bush assembly 137.

  As shown in FIG. 7, the rotating shaft 119 is a columnar member that extends from the inverter motor 105 toward the orbiting scroll 135. The rotating shaft 119 can rotate with respect to the housing 103 based on an axis CE extending in the horizontal direction (left-right direction in FIG. 7) by the first bearing 121 at one end and the second bearing 123 at the other end. It is supported by. As shown in FIG. 8, the rotating shaft 119 has a disc portion 119 </ b> A, an eccentric pin 125, and a limit hole 126.

  The disc portion 119A is provided at one end of the rotary shaft 119 and has a diameter larger than that of the rotary shaft 119 with the axis CE as the center. The disc portion 119A is disposed inside a through portion 121a formed in the first bearing 121, and a circumferential surface is supported by a bearing 122 fixed to the through portion 121a, and the axial center with respect to the first bearing 121. It is provided to be rotatable around CE. The eccentric pin 125 is formed in a cylindrical shape extending along an eccentric LE that is offset from the end surface 119Aa of the disc portion 119A with respect to the axis CE. The limit hole 126 is a hole that is recessed from the end surface 119Aa of the disc portion 119A, and is formed along another eccentricity LE 'that is offset with respect to the axis CE.

  As shown in FIG. 8, the bush assembly 137 is accommodated in the penetrating portion 121 a of the first bearing 121, and is interposed between the eccentric pin 125 of the rotating shaft 119 and the boss 135 c of the orbiting scroll 135. The rotational movement is transmitted as the turning movement of the turning scroll 135. The bush assembly 137 includes a bush 141, a limit pin 142, and a balance weight 143.

  In the bush 141, an eccentric pin 125 is inserted into a circular hole portion 141a formed in a cylindrical shape. And the bush 141 has the contact end surface 141b which contacts the end surface 119Aa of the disc part 119A in the rotating shaft 119 by inserting the eccentric pin 125 in the circular hole part 141a. The bush 141 is inserted into the boss 135 c of the orbiting scroll 135. For this reason, the bush 141 is formed in a circular shape in accordance with the cylindrical shape of the boss 135c. A cylindrical orbiting bearing 145 is interposed between the outer peripheral surface of the bush 141 and the inner peripheral surface of the boss 135c in order to smoothly transmit the eccentric rotation of the bush 141 to the revolution rotation of the orbiting scroll 135.

  The limit pin 142 is a cylindrical member that is disposed between the bush 141 and the disk portion 119 </ b> A and adjusts the revolution radius of the orbiting scroll 135 together with the limit hole 126. As shown in FIG. 8, the limit pin 142 is provided by being fitted into a fitting hole 141 c formed in the bush 141, and the eccentric pin 125 is inserted into the circular hole portion 141 a of the bush 141, and the limit hole 126 is inserted. So as to protrude from the contact end surface 141b along the eccentric LE '. The limit pin 142 is inserted into the limit hole 126 and a gap is formed between the peripheral surfaces thereof. Further, the limit pin 142 has a concave fitting groove 142 a formed on the side surface of the portion inserted into the limit hole 126 over the circumferential surface. The elastic portion 142b is fitted in the fitting groove 142a. The limit pin 142 may be formed as a columnar member, or may be formed as a columnar member having another cross-sectional shape, and is not particularly limited.

  The elastic portion 142 b is fitted in the fitting groove 142 a of the limit pin 142, and contacts the outer peripheral surface of the limit pin 142 and the inner peripheral surface of the limit hole 126 with the limit pin 142 inserted into the limit hole 126. Are substantially cylindrical elastic members. As a material for forming the elastic portion 142b, it is desirable to use a rubber that does not swell while having compatibility with the refrigerant or the lubricating oil of the scroll compressor 101. Specifically, HNBR (hydrogenated nitrile rubber) or the like can be exemplified, but a suitable rubber can be used according to the refrigerant or lubricating oil used.

  The elastic portion 142 b is formed so that the diameter of the outer peripheral surface is equal to or larger than the diameter of the limit hole 126 and the diameter of the inner peripheral surface is equal to or smaller than the diameter of the limit pin 142. The elastic portion 142b is provided with a hook-shaped convex portion that fits into the fitting groove 142a over the inner peripheral surface thereof. The elastic portion 142b has at least rigidity to support the weight of the orbiting scroll 135 and hold the limit pin 142 away from the inner peripheral surface of the limit hole 126 when the orbiting scroll 135 is not driven to be orbited. On the other hand, the rigidity of the elastic portion 142b is such that when the orbiting scroll 135 is driven to rotate and a reaction force due to centrifugal force and refrigerant compression is applied, the limit pin 142 directly contacts the inner peripheral surface of the limit hole 126. It is suppressed to the extent to do.

  As shown in FIG. 9, when the bush assembly 137 is viewed from the disk portion 119A side (the left side in FIGS. 7 and 8), the circular hole portion 141a has two relative positional relationships between the circular hole portion 141a and the limit pin 142. A case where the limit pin 142 is arranged in the 8 o'clock direction when it is arranged in the hour direction can be exemplified.

  The balance weight 143 is a member that adjusts the pressing force of the orbiting scroll 135 against the fixed scroll 133 and balances it. As shown in FIGS. 8 and 9, the balance weight 143 is a bowl-shaped member that extends in a semicircular shape from the circumferential surface on the disk portion 119 </ b> A side of the bush 141 toward the outside in the radial direction. As shown in FIG. 9, the range in which the balance weight 143 extends is a range between the 3 o'clock direction and the 9 o'clock direction when the circular hole portion 141 a is arranged in the 2 o'clock direction. It is offset from the line passing through the center of the bush 141 in the 6 o'clock direction.

  The balance weight 143 includes a connecting portion 143A and a weight 143B. The connecting portion 143 </ b> A is formed in a ring shape, and the hole portion 143 </ b> Aa is joined to the outer peripheral portion of the bush 141. As described above, since the bush 141 is inserted into the boss 135c of the orbiting scroll 135, the connecting portion 143A is disposed at a position near the rotary shaft 119 (contact end surface 141b) in order to prevent interference with the boss 135c of the orbiting scroll 135. It is joined to the bush 141. The weight 143B is provided in a cantilever shape so as to protrude in a direction away from the contact end surface 141b on a part of the outer periphery of the connecting portion 143A.

  As shown in FIG. 8, the rotary shaft 119 and the bush assembly 137 are combined so that the eccentric pin 125 is inserted into the circular hole portion 141 a and the limit pin 142 is inserted into the limit hole 126. The elastic portion 142 b of the limit pin 142 is inserted into the limit hole 126 together with the limit pin 142 and is in contact with the inner peripheral surface of the limit hole 126. Because of this combination, the bush assembly 137 is rotatable within a range regulated by the limit pin 142 and the limit hole 126 with the eccentric pin 125 as the rotation center.

  When the orbiting scroll 135 is driven to revolve, the compression chamber C formed between the fixed scroll 133 takes in and compresses the refrigerant flowing into the scroll compressor 101 from the motor case 103c. Specifically, the compression chamber C takes in the refrigerant at the outer peripheral ends of the fixed scroll 133 and the orbiting scroll 135. Then, due to the revolution of the orbiting scroll 135, the compression chamber C decreases in volume as it moves from the outer peripheral end toward the center side along the fixed side wrap 133b and the movable side wrap 135b, and compresses the taken-in refrigerant. The refrigerant compressed in the compression chamber C is discharged into the discharge chamber 103A through the discharge hole 133c of the fixed scroll 133, and is discharged from the discharge chamber 103A to the outside of the first housing 103a.

  On the orbiting scroll 135, the centrifugal force due to the revolution orbit and the compression reaction force of the refrigerant compressed by the compression chamber C act in the direction of expanding the revolution orbit radius. By these forces, the orbiting scroll 135 and the bush assembly 137 rotate about the eccentric pin 125 and the revolution orbit radius is increased. Then, the limit pin 142 and the limit hole 126 approach each other while pressing the elastic portion 142b and come into contact with each other. When the limit pin 142 and the limit hole 126 are in contact with each other, the rotation range of the bush assembly 137 and the orbiting scroll 135 around the eccentric pin 125 is restricted. Note that the centrifugal force and the compression reaction force acting on the orbiting scroll 135 are large enough to crush the elastic portion 142b. For example, the magnitude of a force of about several thousand N can be exemplified.

  In connection with such an operation, for example, a liquid refrigerant (hereinafter referred to as a liquid refrigerant) exists in the compression chamber C, or a foreign object is caught between the orbiting scroll 135 and the fixed scroll 133. In this case, the revolution scroll radius of the orbiting scroll 135 becomes small, and a passage for liquid refrigerant and foreign matters is formed. That is, the bushing assembly 137 together with the orbiting scroll 135 crushes the elastic portion 142b and centers the eccentric pin 125 by the liquid compression reaction force generated when the liquid refrigerant is compressed and the resistance force generated when the foreign matter is bitten. And rotate in the direction to reduce the revolution turning radius. By this rotation, an escape passage is formed between the orbiting scroll 135 and the fixed scroll 133.

  On the other hand, when the operation of the scroll compressor 101 is stopped and the revolution orbit of the orbiting scroll 135 is stopped, the centrifugal force and the compression reaction force acting on the orbiting scroll 135 disappear, and the force for increasing the revolution radius of the orbiting scroll 135 disappears. . The orbiting scroll 135 is rotated about the eccentric pin 125 by gravity acting downward in the vertical direction, and the limit pin 142 and the limit hole 126 are separated from each other. The elastic part 142b crushed between the limit pin 142 and the limit hole 126 by centrifugal force or the like during the operation of the scroll compressor 101 is also connected to the limit pin 142 and the limit hole 126 by the force of returning from the crushed shape to the original shape. Separate them. Further, the elastic portion 142b holds the limit pin 142 in a state of being separated from the limit hole 126. The elastic portion 142b has a crushing force due to the gravity acting on the orbiting scroll 135 and the bush assembly 137, but its size is about several N and is smaller than the centrifugal force and the compression reaction force. Can be held away from the limit hole 126. Therefore, when the operation of the scroll compressor 101 is stopped, the rattling sound generated by the contact between the limit pin 142 and the limit hole 126 is suppressed.

  Further, when the operation of the scroll compressor 101 is stopped and the liquid refrigerant exists in the compression chamber C, the revolution radius of the orbiting scroll 135 becomes small as described above. That is, the limit pin 142 and the limit hole 126 are separated from each other, and the revolution radius of the orbiting scroll 135 is reduced. At this time, when the limit pin 142 is separated from a predetermined region on the inner peripheral surface of the limit hole 126 and contacts (collises) with the opposite region, the shape of the elastic portion 142b is deformed and the limit pin 142 and the limit portion 142 are limited. The momentum at the time of contact with the hole 126 is reduced. Therefore, the rattling noise generated when the limit pin 142 and the limit hole 126 come into contact with each other when the liquid refrigerant is present in the compression chamber C is suppressed.

  Further, the rattling noise when the revolution turning radius of the turning scroll 135 is not stable or when a foreign object is caught between the turning scroll 135 and the fixed scroll 133 is similarly suppressed by the action of the elastic portion 142b. Is done.

  The configuration is not limited to the configuration in which the escape path is formed between the turning scroll 135 and the fixed scroll 133 by the limit pin 142 and the limit hole 126. For example, although not shown in the figure, a clearance is provided between the circular hole portion 141a of the bush 141 in the bush assembly 137 and the eccentric pin 125 so that the bush assembly 137 can move in the radial direction of the eccentric pin 125, thereby turning An escape passage may be formed between the scroll 135 and the fixed scroll 133.

  FIG. 6 is a plan view of a rotating shaft of another example of the scroll fluid machine according to the present embodiment. As shown in FIG. 6, in the configuration in which a gap is provided between the circular hole portion 141 a of the bush 141 and the eccentric pin 125 in the bush assembly 137, the eccentric pin 125 extends in the extending direction of the axis CE (or the eccentric LE). The outer shape projected onto the head is mainly composed of a first arc 125a and a second arc 125b.

  The first arc 125a is in a range of P11-P12 in FIG. 6 and has a length that exceeds a part of the outer edge 119Ab of the outer shape of the disk portion 119A of the rotating shaft 119 and is centered on the position of the eccentric LE. It is formed within the range of the outer shape of the rotating shaft 119 (here, the disc portion 119A) by one radius Ra.

  The second arc 125b is in the range of P12-P11 in FIG. 6 and has a radius R equal to or less than the radius R forming the outer edge 119Ab of the rotary shaft 119 in a portion where the first radius Ra exceeds the outer edge 119Ab of the outer shape of the rotary shaft 119. The length is formed by a second radius Rb centered on the position of the axis CE.

  That is, in the scroll compressor 101 of the present embodiment, the eccentric pin 125 of the rotating shaft 119 has an eccentric shape LE whose outer shape exceeds a part of the outer edge 119Ab of the rotating shaft 119 (here, the disc portion 119A). A first arc 125a formed within the outer shape range of the rotary shaft 119 by the first radius Ra centered on the position of λ, and a length equal to or less than the radius R forming the outer edge 119Ab at a portion where the first radius Ra exceeds the outer edge 119Ab The second arc 125b is formed by a second radius Rb centered on the position of the axis CE.

  According to the scroll compressor 101, the outer shape of the eccentric pin 125 has a length that exceeds a part of the outer edge 119Ab of the rotating shaft 119 (here, the disc portion 119A) and a first radius centered on the position of the eccentric LE. By having the first arc 125a formed within the range of the outer shape of the rotating shaft 119 by Ra, it is possible to have a large diameter that can exceed a part of the outer edge 119Ab of the rotating shaft 119, and the rigidity of the eccentric pin 125 can be increased. It can be improved. As a result, the occurrence of deflection of the eccentric pin 125 can be suppressed.

  Moreover, the outer shape of the eccentric pin 125 is formed by a second radius Rb having a length equal to or less than the radius R forming the outer edge 119Ab at a portion where the first radius Ra exceeds the outer edge 119Ab and centering on the position of the axis CE. By having the two circular arcs 125b, the outer shape of the eccentric pin 125 is prevented from protruding from the outer edge 119Ab of the rotating shaft 119. If the outer shape of the eccentric pin 125 protrudes from the outer edge 119Ab of the rotary shaft 119 (here, the disk portion 119A), the eccentric pin 125 interferes with the processing of the rotary shaft 119, and the processing takes time. When inserting into the bearings 121 and 123, the eccentric pin 125 gets in the way and takes time to assemble, but such inconvenience can be eliminated.

In the scroll compressor 101 of the present embodiment, the first radius Ra, the second radius Rb, the radius R, and the distance ρ between the position of the axis CE and the position of the eccentric LE are (Ra ² + ρ ^2). ) It is preferable to satisfy the relationship of ^1/2 ≦ Rb ≦ R.

The second arc 125b is formed by a second radius Rb having a length equal to or less than the radius R forming the outer edge 119Ab of the rotary shaft 119 and centered on the position of the axis CE. If the second radius Rb is less than the radius R, The outer shape of the eccentric pin 125 is reduced in diameter. According to the scroll compressor 101, the outer shape of the eccentric pin 125 prevents a reduction in diameter by setting the lower limit of the second radius Rb according to the relationship of (Ra ² + ρ ² ) ^1/2 ≦ Rb ≦ R. Can do. As a result, the rigidity of the eccentric pin 125 can be improved, and the effect of suppressing the deflection of the eccentric pin 125 can be significantly obtained.

  In the bush assembly 137 configured as described above, a moment acts in a direction away from the bush 141 together with the balance weight 143 from the connecting portion 143A by a centrifugal force acting on the weight 143B. Since this moment acts on the joint portion between the bush 141 and the connecting portion 143A, there is a problem that the connecting portion 143A is detached from the bush 141 or the position of the connecting portion 143A is shifted from the bush 141.

  Therefore, in this embodiment, the bush assembly 137 is devised to join the bush 141 and the balance weight 143.

  As shown in FIG. 8, in the scroll compressor 101 of the present embodiment, the connecting portion 143 </ b> A is arranged so as to be shifted in the length direction of the bush 141 (rightward in FIG. 8) with respect to the bush 141. A stepped portion 147 is formed between the contact end surface 141b of the bush 141, which is the surface facing the end surface 119Aa of the disc portion 119A, and the end surface 143Ab of the connecting portion 143A. The stepped portion 147 is formed by attaching the connecting portion 143A to the bush 141 such that the end surface 143Ab of the connecting portion 143A is slightly separated from the end surface 119Aa of the disk portion 119A of the rotating shaft 119 than the contact end surface 141b of the bush 141. The step portion 147 is provided with a joint portion 149 that joins the bush 141 and the connecting portion 143A. The joint portion 149 is formed on the end surface 143Ab of the coupling portion 143A and the side surface of the bush 141 at the stepped portion 147, and does not protrude from the contact end surface 141b of the bush 141 toward the end surface 119Aa side of the disk portion 119A of the rotary shaft 119. Is formed. The joint portion 149 is formed by laser welding. Note that the joint portion 149 may be formed not only by laser welding but also by other welding.

  Thus, in the scroll compressor 101 of the present embodiment, the bush assembly 137 has the contact end surface 141b into which the eccentric pin 125 is inserted and contacts the end surface 119Aa of the rotating shaft 119 (the disk portion 119A), and A bush 141 inserted into a cylindrical boss 135c provided on the bottom surface of the orbiting scroll 135, a connecting portion 143A disposed in the vicinity of the contact end surface 141b on the outer periphery of the bush 141, and an outer periphery of the connecting portion 143A A balance weight 143 having a weight 143B provided in a cantilever shape protruding in part in a direction away from the contact end surface 141b, a stepped portion 147 provided between the connecting portion 143A and the contact end surface 141b of the bush 141, Bush 141 and connecting portion 143A provided on stepped portion 147 are joined. It was provided with a joint portion 149, a.

  According to the scroll compressor 101, the connecting portion 143A is started from the centrifugal force of the weight 143B provided in a cantilevered manner in a direction away from the contact end surface 141b on a part of the outer periphery of the connecting portion 143A. The moment acts to rotate the weight 143B in the direction in which the contact end surface 141b is present, but this moment acts at the stepped portion 147 to bring the connecting portion 143A closer to the bush 141 side. For this reason, an excessive load is not applied to the joint portion 149 provided in the stepped portion 147, the rigidity of the joint between the bush 141 and the connecting portion 143A can be secured, and the connecting portion 143A comes off from the bush 141, This prevents a situation in which the position of the connecting portion 143A is shifted with respect to the bush 141.

  Moreover, since the joint portion 149 that joins the bush 141 and the connecting portion 143A is provided in the stepped portion 147, there is a situation in which the joint portion 149 protrudes from the contact end surface 141b of the bush 141 that contacts the end surface 119Aa of the rotating shaft 119. This prevents the joint 149 from interfering with the end surface 119Aa of the rotary shaft 119, and the processing of the joint 149 for preventing the interference can be omitted. Further, the weight 143B is provided so as to protrude from the connecting portion 143A in a cantilevered direction away from the contact end surface 141b, and the stepped portion 147 is joined between the contact end surface 141b on the opposite side where the weight 143B extends and the connecting portion 143A. Since the portion 149 is provided, the joint portion 149 can be easily provided regardless of the presence of the weight 143B.

  Further, in the scroll compressor 101 of the present embodiment, the bush assembly 37 may be provided with the joint portion 149 on the entire circumference in the circumferential direction of the bush 141, but as shown in FIG. The bush 141 is preferably provided at a plurality of locations (three locations in FIG. 9) in the circumferential direction. The circumferential direction of the bush 141 refers to a direction along the circumferential surface of the bush 141 with the center O of the bush 141 as a reference.

  According to the scroll compressor 101, when the joint portion 149 is formed by welding, the joint portion 149 is provided at a plurality of locations in the circumferential direction of the bush 141 rather than provided at the entire circumference of the bush 141. It is possible to suppress thermal deformation of the bush 141 and the connecting portion 143A due to welding heat.

  Further, in the scroll compressor 101 of the present embodiment, the bush assembly 137 has the joint portions 149 arranged evenly in the circumferential direction of the bush 141 when the joint portions 149 are provided at a plurality of locations in the circumferential direction of the bush 141. It is preferable that In FIG. 9, the joint portions 149 are provided at three locations in the circumferential direction of the bush 141, and are evenly arranged every 120 ° with the center O of the bush 141 as a reference.

  According to the scroll compressor 101, when the joint portion 149 is formed by welding, the joint portion 149 is evenly arranged in the circumferential direction of the bush 141, so that the heat of the bush 141 and the connecting portion 143A due to welding heat. Even if deformation occurs, it can be equalized and local deformation can be suppressed.

  Further, in the scroll compressor 101 of the present embodiment, the bush assembly 137 has the joint portion 149 in the vicinity where the weight 143B is provided when the joint portion 149 is provided at a plurality of locations in the circumferential direction of the bush 141. It is preferable that many are arranged. In addition, when the joining part 149 is evenly arranged in the circumferential direction of the bush 141, as shown in FIG. 9, in the configuration in which the joining part 149 is provided at an odd number in the circumferential direction of the bush 141, the joining part 149 is provided. However, many are arranged in the vicinity where the weight 143B is provided.

  According to the scroll compressor 101, the moment starting from the connecting portion 143 </ b> A acts in the vicinity of the weight 143 </ b> B with the action of the centrifugal force of the weight 143 </ b> B. When provided at a plurality of locations in the direction, the effect of ensuring the rigidity of the joint between the bush 141 and the connecting portion 143A is remarkably obtained by arranging many joint portions 149 near the weight 143B. be able to.

  Further, in the scroll compressor 101 of the present embodiment, as shown in FIG. 9, the bush assembly 137 is provided with an oil supply groove 151 on the outer peripheral portion of the bush 141 along the cylindrical extending direction. It is preferable that 149 is disposed away from the radial range of the oil supply groove 151.

  According to the scroll compressor 101, the oil supply groove 151 is for supplying lubricating oil to the scroll compression mechanism 107. When the joint portion 149 is formed by welding, the joint portion 149 is provided in the oil supply groove 151. By being arranged away from the radial range, thermal deformation of the oil supply groove 151 due to welding heat can be suppressed, and the lubricating oil can be supplied smoothly by the oil supply groove 151.

  Moreover, in the scroll compressor 101 of this embodiment, it is preferable that the bush assembly 137 has the bush 141 formed of a sintered material and the balance weight 143 formed of a cast iron material.

  According to the scroll compressor 101, the bush 141 is a sliding member connected to the eccentric pin 125 and the boss 135c of the orbiting scroll 135, and is preferably formed of a relatively high hardness sintered material. Further, the balance weight 143 includes a weight 143B that balances dynamic unbalance generated by unbalanced weights of the orbiting scroll 135, the boss 135c, the orbiting bearing 145, the bush assembly 137, and the like with the revolution orbiting motion of the orbiting scroll 135. For this reason, it is preferably formed of a relatively high-density cast iron material.

  Moreover, in the scroll compressor 101 of this embodiment, it is preferable that the bush assembly 137 has the bush 141 and the connecting portion 143A of the balance weight 143 fixed by shrink fitting or interference fitting.

  According to the scroll compressor 101, the bush 141 and the connecting portion 143A of the balance weight 143 are fixed by shrink fitting or interference fitting, so that the bush 141 and the connecting portion are combined with the joint portion 149. The effect of ensuring the rigidity of joining with 143A can be remarkably obtained. When the bush 141 and the connecting portion 143A are joined (when the joining portion 149 is provided), the inner diameter of the hole portion 143Aa of the connecting portion 143A is made smaller than the outer diameter of the bush 141, and shrink fitting or interference fitting is performed. Thus, the bush 141 and the connecting portion 143A are fitted together, and then the joint portion 149 is formed by welding. In this manner, the bush 141 and the connecting portion 143A are fitted together in advance by shrink fitting or interference fitting, so that the joint 141 can be formed by welding without causing a deviation between the bush 141 and the connecting portion 143A. .

  Further, in the scroll compressor 101 of the present embodiment, the bush assembly 137 is provided with the bush 141 so as to be rotatable with respect to the eccentric pin 125, and is inserted into the limit hole 126 formed in the end surface 119Aa of the rotary shaft 119 to rotate. A limit pin 142 for restricting the range is provided, and the joint portion 149 is disposed away from a radial range of a portion to which the limit pin 142 is attached (a fitting hole 141c for fitting the limit pin 142). Is preferred.

  According to the scroll compressor 101, when the joint portion 149 is formed by welding, the joint portion 149 is disposed away from the radial range of the part to which the limit pin 142 is attached, so that the limit is caused by welding heat. The thermal deformation of the part where the pin 142 is attached can be suppressed, and the situation where the attachment of the limit pin 142 is hindered can be suppressed.

  In the scroll compressor 101 described above, the limit hole 126 is formed in the end surface 119Aa of the rotary shaft 119 and the limit pin 142 is attached to the bush 141, but this is not restrictive. Although not shown in the drawing, the limit pin 142 may be attached to the end surface 119Aa of the rotating shaft 119, and the limit hole 126 may be formed in the bush 141.

  In this case, in the scroll compressor 101 of the present embodiment, the bush assembly 137 includes a limit pin 142 that is provided on the end surface 119Aa of the rotary shaft 119, and the bush 141 is rotatably provided to the eccentric pin 125. It is preferable that a limit hole 126 for restricting the rotation range is provided, and the joint portion 149 is disposed away from a radial range of a portion where the limit hole 126 is formed.

  According to the scroll fluid machine 101, when the joint portion 149 is formed by welding, the joint portion 149 is arranged away from the radial range of the portion where the limit hole 126 is formed, so that the welding heat It is possible to suppress thermal deformation of a portion where the limit hole 126 is formed, and it is possible to suppress a situation in which the accuracy of the rotation range regulated by the limit hole 126 is lowered.

  Moreover, in the scroll compressor 101 of this embodiment, the maximum rotation speed of the rotating shaft 119 exceeds 145 rps.

  According to the scroll compressor 101, the occurrence of deflection of the eccentric pin 125 can be suppressed by the above-described configuration, and the rigidity of the joint between the bush 141 and the connecting portion 143A in the bush assembly 137 can be ensured. Therefore, the scroll compressor 101 in which the maximum rotational speed of the rotary shaft 119 exceeds 145 rps can be realized.

  The scroll fluid machine is not limited to the scroll compressors 1 and 101, but may be a scroll expander. A scroll expander that is a scroll fluid machine, although not explicitly shown in the figure, generates a rotational driving force on the rotary shaft while the orbiting scroll that meshes with the fixed scroll rotates by expanding the fluid. That is, the configuration of the eccentric pins 25 and 125 of the rotary shafts 19 and 119 and the configuration of the bush assemblies 37 and 137 of the scroll compression mechanisms 7 and 107 can be applied to the scroll expander.

1,101 Scroll compressor (scroll fluid machine)
3,103 Housing 19,119 Rotating shaft 19a, 119Aa Upper end surface (end surface)
19b, 119Ab Outer edge 25, 125 Eccentric pin 25c Pin side slide surface 33, 133 Fixed scroll 35, 135 Orbiting scroll 35c, 135c Boss 37, 137 Bush assembly 41, 141 Bush 41b, 141b Contact end surface 41c Bush side slide surface 43, 143 Balance weight 43A, 143A Connecting portion 43Aa, 143Aa Hole portion 43B, 143B Weight 47, 147 Stepped portion 49, 149 Joint portion 51, 151 Oil supply groove CE Axle LE Eccentric

Claims (11)

A fixed scroll fixed to the housing;
A orbiting scroll provided to be capable of orbiting while meshing with the fixed scroll;
A rotating shaft having an eccentric pin supported rotatably with respect to the housing and eccentric with respect to an axis;
A bushing assembly interposed between the eccentric pin and the orbiting scroll to transmit the rotational movement of the eccentric pin as the orbiting scroll;
A scroll fluid machine comprising:
The bush assembly is
A bush that has a contact end surface that is inserted into the eccentric pin and contacts an end surface of the rotary shaft, and that is inserted into a cylindrical boss provided on the bottom surface of the orbiting scroll;
A balance weight having a connecting portion disposed in the vicinity of the contact end surface at the outer peripheral portion of the bush, and a weight provided in a cantilever manner extending in a direction away from the contact end surface at a part of the outer periphery of the connecting portion When,
A step portion provided between the connecting portion and the contact end surface of the bush;
A joint provided on the stepped portion and joining the bush and the connecting portion;
A scroll fluid machine comprising:   2. The scroll fluid machine according to claim 1, wherein the bush assembly is provided with a plurality of joint portions in a circumferential direction of the bush. 3.   3. The scroll fluid machine according to claim 2, wherein the joint portion of the bush assembly is evenly arranged in a circumferential direction of the bush.   4. The scroll fluid machine according to claim 2, wherein the bush assembly has a large number of joints disposed in the vicinity of the weight. 5.   In the bush assembly, an oil supply groove is provided along a cylindrical extending direction in an outer peripheral portion of the bush, and the joint portion is disposed away from a radial range of the oil supply groove. The scroll fluid machine according to any one of claims 2 to 4, wherein   The scroll fluid machine according to any one of claims 1 to 5, wherein the bush assembly is formed of a sintered material, and the balance weight is formed of a cast iron material.   The scroll fluid machine according to any one of claims 1 to 6, wherein in the bush assembly, the bush and the connecting portion of the balance weight are fixed by shrink fitting or interference fitting.   The bush assembly is provided with a bush side slide surface in contact with a pin side slide surface provided on a side of the eccentric pin on an inner peripheral portion of the bush so as to be slidable with respect to the eccentric pin. The scroll fluid machine according to any one of claims 2 to 7, wherein the joint portion is disposed apart from a radial range of the bush side slide surface.   The bush assembly is provided with a limit pin that is provided so that the bush is rotatable with respect to the eccentric pin and is inserted into a limit hole formed in an end surface of the rotary shaft to restrict a rotation range, The scroll fluid machine according to any one of claims 2 to 7, wherein the portion is disposed apart from a radial range of a portion to which the limit pin is attached.   The bush assembly is provided with a limit hole for restricting a rotation range by inserting a limit pin fixed to an end surface of the rotating shaft, the bush being provided rotatably with respect to the eccentric pin, and the joining The scroll fluid machine according to any one of claims 2 to 7, wherein the portion is disposed apart from a radial range of a portion where the limit hole is formed.   The scroll fluid machine according to any one of claims 1 to 10, wherein a maximum rotation speed of the rotary shaft exceeds 145 rps.

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