JP6685689B2 - Scroll fluid machinery - Google Patents

Description

  The present invention relates to a scroll fluid machine.

  A scroll compressor, which is a scroll fluid machine, mainly includes a fixed scroll, an orbiting scroll, a rotary 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 to orbit and compresses the fluid.

  Conventionally, for example, Patent Literature 1 discloses a slide bush that adjusts the revolution radius of an orbiting scroll in a scroll fluid machine in accordance with a spiral shape. The spiral wraps of the orbiting scroll and the fixed scroll are designed based on a predetermined optimum revolution radius, but if a gap occurs between the meshes of the wraps due to dimensional tolerance, fluid will flow from the gap. There is a leaking problem. The slide bush is inserted into a cylindrical boss of an orbiting scroll, and a bush into which an eccentric pin of a rotary shaft is inserted, a connecting portion connected to a side portion of the bush, and a balance integrally formed with the connecting portion. It consists of a weight and. This slide bush is constructed so that the bush can slide in the radial direction of the rotating shaft with respect to the eccentric pin, so that the diameter of the slide bush is affected by the gas pressure in the scroll compression chamber, the centrifugal force on the orbiting scroll, and the centrifugal force on the balance weight. By slidingly moving in the direction to change the revolution radius of the boss in which the bush is inserted, the wraps of the orbiting scroll and the fixed scroll are brought into contact with each other and the generation of a gap therebetween is suppressed.

JP, 2003-343454, A

  By the way, the force acting on the bush also acts on the eccentric pin inserted in the bush. When the rotary shaft is rotated at a high speed to improve the capacity, the centrifugal force increases, and the centrifugal force acts on the eccentric pin excessively, causing the eccentric pin to bend in the radial direction. Due to the deflection of the eccentric pin, there is a problem that the bearing supporting the rotary shaft is partially biased.

  The present invention solves the above-mentioned problems, and an object of the present invention is to provide a scroll fluid machine capable of suppressing the occurrence of deflection of an eccentric pin.

  To achieve the above object, a scroll fluid machine according to the present invention includes a fixed scroll fixed to a housing, an orbiting scroll provided so as to orbit while meshing with the fixed scroll, and rotatable with respect to the housing. A rotating shaft having an eccentric pin eccentrically supported by the eccentric shaft, and a bush interposed between the eccentric pin and the orbiting scroll for transmitting the rotational movement of the eccentric pin as the orbiting movement of the orbiting scroll. In the scroll fluid machine, the outer shape of the eccentric pin has an outer shape of the rotating shaft with a first radius Ra centered on the position of the eccentricity with a length exceeding a part of an outer edge of the rotating shaft. And a radius that forms the outer edge in a portion where the first radius Ra exceeds the outer edge. And having a, a second circular arc which is formed by a second radius Rb to around the position of the axis in the following length.

  According to this scroll fluid machine, the outer shape of the eccentric pin is formed within the range of the outer shape of the rotating shaft by the first radius Ra centered on the position of the eccentricity with a length exceeding a part of the outer edge of the rotating shaft. By having the first arc, the diameter of the rotary shaft can exceed a part of the outer edge of the rotary shaft, and the rigidity of the eccentric pin can be improved. As a result, the deflection of the eccentric pin can be suppressed.

  Moreover, according to this scroll fluid machine, the outer shape of the eccentric pin has a second radius Rb centered on the position of the axial center with a length equal to or shorter than the radius R forming the outer edge in the portion where the first radius Ra exceeds the outer edge. By having the second arc formed, the outer shape of the eccentric pin is prevented from protruding from the outer edge of the rotary shaft. If the outer shape of the eccentric pin protrudes from the outer edge of the rotating shaft, the eccentric pin interferes with the processing of the rotating shaft, and it takes time to process, or the eccentric pin interferes when the rotating shaft is inserted into the bearing. It takes time and effort, but such inconvenience can be eliminated.

In the scroll fluid machine of the present invention, the first radius Ra, the second radius Rb, the radius R, and the distance ρ between the axial center position and the eccentric position are (Ra ² + ρ). ² ) It is characterized in that the relationship of ^1/2 ≤ Rb ≤ R is satisfied.

The second arc is formed by a second radius Rb having a length equal to or less than the radius R forming the outer edge of the rotary shaft and centered on the axial center position. However, when the second radius Rb is equal to or less than the radius R, the eccentric pin is outside. The shape becomes smaller. According to this scroll fluid machine, it is possible to prevent the outer shape of the eccentric pin from being thinned by setting the lower limit of the second radius Rb according to the relationship of (Ra ² + ρ ² ) ^1/2 ≦ Rb ≦ R. . As a result, the rigidity of the eccentric pin can be improved, and the effect of suppressing the deflection of the eccentric pin can be remarkably obtained.

  Further, in the scroll fluid machine of the present invention, the eccentric pin has a contact end surface that comes into contact with the end surface of the rotating shaft, and is inserted into a cylindrical boss provided on the bottom surface of the orbiting scroll. A bush, a connecting portion arranged in the outer peripheral portion of the bush in the vicinity of the contact end surface, and a weight provided in a cantilever shape on a part of the outer periphery of the connecting portion so as to project in a direction away from the contact end surface. A bush including a balance weight having, a step portion provided between the connecting 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. It is characterized by having an assembly.

  According to this scroll fluid machine, the moment generated from the connecting portion as a starting point is caused by the action of the centrifugal force of the weight, which is provided on a part of the outer periphery of the connecting portion in a cantilever manner in the direction away from the contact end surface. Acts to rotate the contact end surface in a certain direction, and this moment acts to bring the connecting portion closer to the bush side in the step portion. For this reason, an excessive load is not applied to the joint provided in the step portion, the rigidity of the joint between the bush and the connecting portion can be secured, the connecting portion is disengaged from the bush, or the connecting portion is not connected to the bush. Prevents the situation where the position of is shifted.

  Moreover, according to this scroll fluid machine, since the joint portion that joins the bush and the connecting portion is provided in the step portion, it is possible to prevent the joint portion from protruding from the contact end surface of the bush that contacts the end surface of the rotating shaft. Therefore, the joint portion does not interfere with the end surface of the rotary shaft, and the machining of the joint portion for preventing the interference can be omitted. In addition, since the weight is provided in a cantilever manner so as to project from the connecting portion in a direction away from the contact end surface, and the step portion has a joining portion between the contact end surface on the opposite side from which the weight projects and the connecting portion. The joint can be easily provided regardless of the presence of the weight.

  Further, in the scroll fluid machine of the present invention, the bush assembly is characterized in that the joint portions are provided at a plurality of positions in the circumferential direction of the bush.

  According to this scroll fluid machine, when the joint portion is formed by welding, it is more preferable that the joint portion is provided at a plurality of positions in the circumferential direction of the bush rather than being provided at the entire circumference in the circumferential direction of the bush. It is possible to suppress thermal deformation of the bush and the connecting portion due to welding heat.

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

  According to this scroll fluid machine, when the joints are formed by welding, the joints are evenly arranged in the circumferential direction of the bush, so that even if thermal deformation of the bushes and the connecting portion due to welding heat occurs. Can be suppressed 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 near the weight.

  According to this scroll fluid machine, as the centrifugal force of the weight acts, the moment originating from the connecting portion acts near the weight, so that the joints are provided at a plurality of positions in the circumferential direction of the bush. In such a case, by arranging a large number of joints in the vicinity of the weight, the effect of ensuring the rigidity of the joint between the bush and the connecting portion can be remarkably obtained.

  Further, in the scroll fluid machine of the present invention, the bush assembly is provided with an oil supply groove on an outer peripheral portion of the bush along a tubular extending direction, and the joint portion is provided in a radial direction of the oil supply groove. It is characterized in that it is placed away from the range.

  According to this scroll fluid machine, the oil supply groove is for supplying the lubricating oil, and when the joint portion is formed by welding, the joint portion is arranged away from the radial range of the oil supply groove. By this, it is possible to suppress thermal deformation of the oil supply groove due to welding heat, and it is possible to smoothly supply the lubricating oil through the oil supply groove.

  Further, in the scroll fluid machine of the present invention, the bush assembly is characterized in that the bush is made of a sintered material and the balance weight is made 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 preferable that the bush is made of a relatively high hardness sintered material. Further, since the balance weight has a weight that balances the dynamic unbalance generated by the unbalanced weight caused by the orbiting motion of the orbiting scroll, it is preferable that the balance weight is formed of a relatively high density cast iron material.

  Further, 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 shrink fitting.

  According to this scroll fluid machine, since the bush and the connecting portion of the balance weight are fixed by shrink fitting or shrink fitting, the rigidity of the joint between the bush and the connecting portion is increased in synergy with the provision of the joint portion. The effect of securing can be remarkably obtained.

  Further, in the scroll fluid machine of the present invention, the bush assembly is provided with a bush-side slide surface that is 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 apart from a 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 moves from the radial range of the bush-side slide surface. Since they are arranged apart from each other, thermal deformation of the bush-side sliding surface due to welding heat can be suppressed, and the bush assembly can be smoothly moved.

  Further, the scroll fluid machine of the present invention is characterized in that 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 suppress the occurrence of deflection of the eccentric pin, and it is possible to secure the rigidity of the joint between the bush and the connecting portion in the bush assembly, so that the rotary shaft It is possible to realize a scroll fluid machine whose maximum rotation speed exceeds 145 rps.

  According to the present invention, it is possible to suppress the occurrence of bending of the eccentric pin.

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 rotary shaft in the scroll fluid machine according to the embodiment of the present invention. FIG. 3 is a side sectional view of a combination of the rotating shaft and the bush assembly in the scroll fluid machine according to the 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 sectional view of another example of the scroll fluid machine according to the embodiment of the present invention. FIG. 8 is a side sectional view in which a rotary shaft and a bush assembly of another example of the scroll fluid machine according to the embodiment of the present invention are combined. FIG. 9 is a bottom view of a bush assembly of another example of the scroll fluid machine according to the embodiment of the present invention.

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

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

  In FIG. 1, as a scroll fluid machine, a scroll compressor 1 that compresses and discharges a sucked fluid is shown. Further, the scroll compressor 1 of the present embodiment is interposed in a refrigerant flow path that circulates a refrigerant in an air conditioner, a refrigerator, or the like.

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

  The housing 3 is provided with a cylindrical housing body 3a extending vertically, a bottom portion 3b closing the lower end of the housing body 3a, and a lid portion 3c closing the upper end of the housing body 3a, and the whole is sealed. It is a pressure vessel. The housing body 3a is provided with a suction pipe 9 on its side part for introducing a refrigerant into the housing 3. A discharge pipe 11 for discharging the refrigerant compressed by the scroll compression mechanism 7 is provided on the top of the lid 3c. The housing 3 is provided with a discharge cover 13 between the housing body 3 a and the lid portion 3 c, and the inside of the housing 3 has a low pressure chamber 3 A below the discharge cover 13 and a high pressure chamber 3 B above the discharge cover 13. It is divided into The discharge cover 13 is provided 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 inside the housing 3 is configured as an oil reservoir in which lubricating oil is stored.

  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 of the housing body 3a in the vertical direction. The rotor 17 is rotatably provided with respect to the stator 15. The rotary 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.

  An end portion of the rotary shaft 19 is provided above and below the rotor 17 so as to project, and an upper center portion of the housing main body 3a extends in the vertical direction by an upper bearing 21 and a lower end portion thereof extends in a vertical direction CE. It is rotatably supported on the basis of. An eccentric pin 25 is formed at the upper end of the rotary shaft 19 so as to project upward along an eccentricity LE that is eccentric 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 provided with oil supply holes 27 that penetrate vertically in the interior thereof. Further, the lower end of the rotary shaft 19 reaches the oil sump, 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 of the rotary shaft 19 and rotatably supports the rotary shaft 19. The upper bearing 21 is formed with a recess 21a on the upper surface thereof so as to surround the upper end of the rotating shaft 19 which is penetrated. The recess 21a accommodates a bush assembly 37, which will be described later, and stores the lubricating oil fed by the oil supply pump 29 through the oil supply hole 27. Then, the stored lubricating oil is supplied to the scroll compression mechanism 7.

  Further, the upper bearing 21 has a notch 21b formed in a part of its outer periphery so as to have a gap with the inner wall surface of the housing body 3a of the housing 3, and an oil drain hole 21c which communicates the notch 21b with the recess 21a. ing. A cover plate 31 is provided below the notch 21b of the upper bearing 21. The cover plate 31 is provided so as to extend in the vertical direction. The cover plate 31 is formed so as to be curved with its both ends facing the inner wall surface of the housing body 3a so as to cover the periphery of the cutout 21b, and is bent so that the lower end gradually approaches the inner wall surface of the housing body 3a. Has been done. Then, the oil drain hole 21c discharges the excess lubricant oil stored in the recess 21a to the outer periphery of the upper bearing 21 through 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 by the cover plate 31 toward the inner wall surface is returned to the bottom oil sump in the housing 3 along the inner wall surface by the cover plate 31.

  The scroll compression mechanism 7 is disposed inside the housing 3 in the low pressure chamber 3A below the discharge cover 13 and above the upper bearing 21. The scroll compression mechanism 7 includes a fixed scroll 33, an orbiting scroll 35, and a bush assembly 37. , Are provided.

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

  In the orbiting scroll 35, a spiral movable side wrap 35b is formed 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 meshed with each other with their phases shifted from each other, thereby compressing the end plates 33a, 35a and the respective wraps 33b, 35b. A chamber is formed. Further, 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 (lower surface in FIG. 1) of the movable side end plate 35a and the eccentric rotation of the eccentric pin 25 is transmitted. Are formed. The orbiting scroll 35 is prevented from rotating on the basis of the eccentric rotation of the eccentric pin 25 by a rotation preventing mechanism 39 such as a well-known Oldham link arranged between the outer surface of the movable end plate 35a and the upper bearing 21. While being orbited.

  The bush assembly 37 is housed in the recess 21a of the upper bearing 21 described above, and is interposed between the eccentric pin 25 of the rotating shaft 19 and the boss 35c of the orbiting scroll 35 to prevent the eccentric pin 25 from rotating. It is transmitted as turning 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 mesh between the movable side wrap 35b of the orbiting scroll 35 and the fixed side wrap 33b of the fixed scroll 33. The detailed structure of the bush assembly 37 will be described later.

  In this scroll compression mechanism 7, the low-pressure refrigerant introduced into the low-pressure chamber 3A in the housing 3 via the suction pipe 9 is compressed between the fixed scroll 33 and the orbiting scroll 35 by the orbiting scroll 35 revolving around. It is compressed while being sucked into the room. 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 end plate 33a, and the discharge reed valve 13b of the discharge cover 13 is opened by its own pressure, and the high pressure chamber is opened from the opening hole 13a. 3B, and is discharged to the outside of the housing 3 via the discharge pipe 11.

  FIG. 2 is a plan view of the rotary shaft in the scroll fluid machine according to the present embodiment. FIG. 3 is a side sectional 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 the eccentric pin 25 having the eccentricity LE which is eccentric with respect to the axis CE as described above. The eccentric pin 25 is formed so as to project upward from the upper end surface 19a of the rotary shaft 19. The eccentric pin 25 has an outer shape projected in the extending direction of the axis CE (or the eccentric LE) mainly composed of a first circular arc 25a, a second circular arc 25b, and a pin side sliding surface 25c. There is.

  The first arc 25a is a range of P1-P2 in FIG. 2, and is rotated by a first radius Ra centered 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 outer shape of the shaft 19.

  The second circular arc 25b is in the range of P2-P3 in FIG. 2, and in a portion where the first radius Ra exceeds the outer edge 19b of the outer shape of the rotating shaft 19, the radius R is equal to or less than the radius R forming the outer edge 19b of the rotating shaft 19. It is formed by a second radius Rb whose length is 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 length whose outer shape exceeds a part of the outer edge 19b of the rotary shaft 19 and is centered on the position of the eccentric LE. The first circular arc 25a formed by the radius Ra within the outer shape of the rotating shaft 19 and the position of the axis CE at a length equal to or shorter than the radius R that forms the outer edge 19b at the portion where the first radius Ra exceeds the outer edge 19b. And a second arc 25b formed by a second radius Rb which is the center.

  According to this scroll compressor 1, the outer shape of the eccentric pin 25 has a length that exceeds a part of the outer edge 19b of the rotary shaft 19 and has a first radius Ra centered on the position of the eccentric LE. By having the first circular arc 25a formed within the range, the diameter can be made large enough to exceed a part of the outer edge 19b of the rotary shaft 19, and the rigidity of the eccentric pin 25 can be improved. As a result, the deflection of the eccentric pin 25 can be suppressed.

  Moreover, the outer shape of the eccentric pin 25 is formed by the second radius Rb centered at the position of the axis CE with a length equal to or shorter than the radius R forming the outer edge 19b in the portion where the first radius Ra exceeds the outer edge 19b. Having the two arcs 25b prevents the outer shape of the eccentric pin 25 from protruding from the outer edge 19b of the rotary shaft 19. If 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 machining of the rotary shaft 19 and the machining is troublesome, or when the rotary shaft 19 is inserted into the bearings 21 and 23. In addition, the eccentric pin 25 becomes a hindrance and it takes a lot of time to assemble, but such inconvenience can be eliminated.

Further, 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 axial center 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 circular arc 25b is formed by a second radius Rb having a length equal to or shorter than the radius R forming the outer edge 19b of the rotary shaft 19 and centered on the position of the axial center CE, but when the second radius Rb is equal to or smaller than the radius R. The outer shape of the eccentric pin 25 is reduced in diameter. According to this scroll compressor 1, by setting the lower limit of the second radius Rb in accordance with the relationship of (Ra ² + ρ ² ) ^1/2 ≦ Rb ≦ R, the outer shape of the eccentric pin 25 prevents the diameter from being reduced. You can 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 remarkably 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, in the bush 41, the eccentric pin 25 is inserted into a cylindrical hole portion 41a. The bush 41 has a contact end surface 41b that comes into contact with the upper end surface 19a of the rotary shaft 19 by inserting the eccentric pin 25 into the hole 41a. Further, the bush 41 is inserted into the boss 35c of the orbiting scroll 35 as shown in FIG. Therefore, the bush 41 is formed into a circular outer shape in conformity 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 35c in order to smoothly transfer the eccentric rotation of the bush 41 to the orbiting 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. Further, the bush 41 is formed so that the inner shape of the hole 41a is larger than the outer shape of the eccentric pin 25 in the direction along the radial direction of the eccentric LE on the pin side slide surface 25c. Therefore, in the bush 41, since the hole 41a has a larger diameter than the outer shape of the eccentric pin 25, the bush side slide surface 41c slides with respect to the pin side slide surface 25c. It is provided so as to be slidable along.

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

  The connecting portion 43A is formed in a ring shape, and the hole portion 43Aa 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 provided 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 shape on a part of the outer periphery of the connecting portion 43A so as to project in a direction away from the contact end surface 41b of the bush 41 (upward in FIG. 3). As shown in FIGS. 3 and 4, the weight 43B is opposite to the direction in which the eccentric pin 25 is biased with respect to the rotary shaft 19 when the bush assembly 37 is inserted and attached to the eccentric pin 25 of the rotary shaft 19. Arranged in the direction. The weight 43B is positioned by positioning the bush-side slide surface 41c of the hole 41a of the bush 41 against the pin-side slide surface 25c of the eccentric pin 25. That is, the bush assembly 37 can be slid with respect to the eccentric pin 25, but is attached in a state in which it is prevented from rotating.

  Further, as described above, since the bush 41 is inserted into the boss 35c of the orbiting scroll 35, the weight 43B is arranged with a space allowing the boss 35c (and the orbiting bearing 45) to be inserted between the weight 43B and the bush 41. Further, they are arranged in an arc shape (or a fan shape) along the outer shape of the bush 41.

  The bush assembly 37 configured in this manner transmits the rotational movement of the eccentric pin 25 as the orbital movement of the orbiting scroll 35. At this time, the bush assembly 37 is on the opposite side of the eccentric pin 25 from the axis CE. The weight 43B disposed in the rotative movement of the eccentric pin 25 rotates with the eccentric pin 25. The mechanical imbalance is balanced by the centrifugal force acting on the weight 43B. Moreover, since the bush assembly 37 is slidable with respect to the eccentric pin 25, the revolution radius of the boss 35c in which the bush 41 is inserted is changed (that is, the orbiting scroll 35 is slid), and the fixed scroll 33 is moved. Of the orbiting scroll 35 by adjusting the orbiting radius of the orbiting scroll 35 so as to eliminate the gap due to the dimensional tolerance between the fixed side wrap 33b and the orbiting scroll 35 movable side wrap 35b. Generation of a gap is suppressed and fluid leakage is prevented from the gap.

  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 as a starting point by a centrifugal force acting on the weight 43B. Since this moment acts on the joint between the bush 41 and the connecting portion 43A, there is a problem that the connecting portion 43A is disengaged from the bush 41 or the position of the connecting portion 43A is displaced with respect to the bush 41.

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

  As shown in FIG. 3, in the scroll compressor 1 according to the present embodiment, the connecting portion 43A is arranged so as to be displaced from the bush 41 in the longitudinal direction of the bush 41 (the upper side in FIG. 3), and A step 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 apart from the contact end surface 41b of the bush 41 from the upper end surface 19a of the rotary shaft 19. The step portion 47 is provided with a joint portion 49 that joins the bush 41 and the connecting portion 43A. The joining portion 49 is formed on the lower surface 43Ab of the connecting portion 43A and the side surface of the bush 41 in the step portion 47 so as not to project to the upper end surface 19a side of the rotary shaft 19 beyond the contact end surface 41b of the bush 41. . The joint 49 is formed by laser welding. The joint 49 is not limited to laser welding and may be formed by other welding.

  As described above, in the scroll compressor 1 according to the present embodiment, the eccentric pin 25 is inserted and has the contact end surface 41 b that comes into contact with the end surface 19 a of the rotating shaft 19, and has a cylindrical shape provided on the bottom surface of the orbiting scroll 35. The bush 41 inserted into the boss 35c, the connecting portion 43A arranged in the outer peripheral portion of the bush 41 near the contact end surface 41b, and a part of the outer periphery of the connecting portion 43A projecting in a direction away from the contact end surface 41b. A balance weight 43 having a cantilevered weight 43B, a step portion 47 provided between the connecting portion 43A and the contact end surface 41b of the bush 41, and a bush 41 and the connecting portion 43A provided on the step portion 47. And a bushing assembly 37 including a joint portion 49 in which

  According to this scroll compressor 1, the connecting portion 43A is used as a starting point in accordance with the action of the centrifugal force of the weight 43B, which is provided on a part of the outer periphery of the connecting portion 43A in a cantilever manner in the direction away from the contact end surface 41b. The generated moment acts to rotate the weight 43B in the direction in which the contact end surface 41b is present, but in the step portion 47, the moment acts to bring the connecting portion 43A closer to the bush 41 side. Therefore, an excessive load is not applied to the joint portion 49 provided on the stepped portion 47, the rigidity of the joint between the bush 41 and the joint portion 43A can be secured, and the joint portion 43A is disengaged from the bush 41, The situation where the position of the connecting portion 43A is displaced with respect to the bush 41 is prevented.

  Moreover, since the joint portion 49 that joins the bush 41 and the connecting portion 43A is provided in the step portion 47, it is possible to prevent the joint portion 49 from protruding from the contact end surface 41b of the bush 41 that contacts the end surface 19a of the rotary shaft 19. It is possible to prevent the joint portion 49 from interfering with the end surface 19a of the rotary shaft 19, and it is possible to omit the processing of the joint portion 49 for preventing the interference. In addition, the weight 43B is provided in a cantilever manner so as to project from the connecting portion 43A 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 from which the weight 43B projects 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 have the joint portion 49 provided on the entire circumference in the circumferential direction of the bush 41, but as shown in FIG. The bush 41 is preferably provided at a plurality of positions (three positions in FIG. 5) in the circumferential direction. The circumferential direction of the bush 41 refers to the circumferential direction based on the position of the eccentric LE of the eccentric pin 25.

  According to this scroll compressor 1, when the joint portion 49 is formed by welding, the joint portion 49 is provided at a plurality of positions in the circumferential direction of the bush 41 rather than being provided at the entire circumference in the circumferential direction of the bush 41. By doing so, thermal deformation of the bush 41 and the connecting portion 43A due to welding heat can be suppressed.

  Further, in the scroll compressor 1 of the present embodiment, in the bush assembly 37, when the joint portions 49 are provided at a plurality of positions in the circumferential direction of the bush 41, the joint portions 49 are evenly arranged in the circumferential direction of the bush 41. Is preferably provided. In FIG. 5, the joints 49 are provided at three locations in the circumferential direction of the bush 41 and are evenly arranged at every 120 ° with the eccentricity LE of the eccentric pin 25 as a reference.

  According to this scroll compressor 1, when the joint portion 49 is formed by welding, the joint portions 49 are 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 the welding heat. Even if deformation occurs, it is possible to equalize and suppress local deformation.

  Further, in the scroll compressor 1 of the present embodiment, in the bush assembly 37, when the joint portions 49 are provided at a plurality of positions in the circumferential direction of the bush 41, the joint portions 49 are provided near the weight 43B. It is preferable that a large number of them are arranged. When the joint portions 49 are evenly arranged in the circumferential direction of the bush 41, as shown in FIG. 5, in the configuration in which the joint portions 49 are provided at odd-numbered locations in the circumferential direction of the bush 41, the joint portions 49 are provided. However, many are arranged near the weight 43B.

  According to the scroll compressor 1, the moment from the connecting portion 43A as a starting point acts in the vicinity of the weight 43B in accordance with the action of the centrifugal force of the weight 43B. In the case of being provided at a plurality of positions in the direction, by arranging a large number of the joint portions 49 in the vicinity of the weight 43B, the effect of ensuring the rigidity of the joint between the bush 41 and the connecting portion 43A is obtained remarkably. be able to.

  Further, in the scroll compressor 1 of the present embodiment, as shown in FIGS. 4 and 5, the bush assembly 37 is provided with the oil supply groove 51 on the outer peripheral portion of the bush 41 along the tubular extending direction. It is preferable that the joint portion 49 is arranged 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 the lubricating oil to the scroll compression mechanism 7, and when the joint portion 49 is formed by welding, the joint portion 49 is formed in the oil supply groove 51. By disposing the oil supply groove 51 away from the radial range, thermal deformation of the oil supply groove 51 due to welding heat can be suppressed, and lubricating oil can be smoothly supplied by the oil supply groove 51.

  Further, in the scroll compressor 1 of the present embodiment, it is preferable that in the bush assembly 37, the bush 41 is made of a sintered material and the balance weight 43 is made of a cast iron material.

  According to this 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 made of a relatively high hardness sintered material. Further, the balance weight 43 has a weight 43B that balances the 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 in accordance with the orbiting movement of the orbiting scroll 35. Therefore, it is preferably formed of a relatively high density cast iron material.

  In the scroll compressor 1 of the present embodiment, it is preferable that the bush assembly 37 has the bush 41 and the connecting portion 43A of the balance weight 43 fixed by shrink fitting or shrink fitting.

  According to the scroll compressor 1, since the bush 41 and the connecting portion 43A of the balance weight 43 are fixed by shrink fitting or shrink fitting, the bush 41 and the connecting portion are synergistic with the provision of the joint 49. The effect of ensuring the rigidity of the joint with 43A can be remarkably obtained. When the bush 41 and the connecting portion 43A are joined (when the joining portion 49 is provided), the inner diameter of the hole portion 43Aa of the connecting portion 43A is formed smaller than the outer diameter of the bush 41, and the shrink fitting or shrink fitting is performed. The bush 41 and the connecting portion 43A are fitted with each other, and then the joint portion 49 is formed by welding. In this way, by fitting the bush 41 and the connecting portion 43A in advance by shrink fitting or shrink fitting, the bushing 41 and the connecting portion 43A can be welded to each other to form the joint portion 49 without displacement. .

  Further, in the scroll compressor 1 of the present embodiment, in the bush assembly 37, when the joint portions 49 are provided at a plurality of positions in the circumferential direction of the bush 41, as shown in FIG. It is preferably arranged away from the radial range of the side slide surface 41c.

  According to this scroll compressor 1, the bush-side slide surface 41c is a portion that supports the sliding movement of the bush assembly 37, and when the joint portion 49 is formed by welding, the joint portion 49 forms the bush-side slide surface 41c. Since the bush side slide surface 41c is arranged away from the radial range, the bush side slide surface 41c can be prevented from being thermally deformed, and the bush assembly 37 can be smoothly moved.

  Further, in the scroll compressor 1 of the present embodiment, the maximum rotation speed of the rotary shaft 19 exceeds 145 rps.

  According to this scroll compressor 1, with the above-described configuration, it is possible to suppress the occurrence of deflection of the eccentric pin 25, and to secure the rigidity of the joint between the bush 41 and the connecting portion 43A in the bush assembly 37. Therefore, it is possible to realize the scroll compressor 1 in which the maximum rotation speed of the rotating shaft 19 exceeds 145 rps.

  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 sectional view in which a rotating shaft and a bush assembly of another example of the scroll fluid machine according to the present embodiment are combined. FIG. 9 is a bottom view of a bush assembly of another example of the scroll fluid machine according to the present embodiment.

  In FIG. 7, as a scroll fluid machine, a scroll compressor 101 that compresses and discharges the sucked fluid is shown. Further, the scroll compressor 101 is interposed in a refrigerant flow path that circulates a refrigerant in an air conditioner, a refrigerator, etc., and is particularly used for 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. , Are provided. As shown in FIG. 8, the fixed scroll 133, the orbiting scroll 135, and the bush assembly 137 form a scroll compression mechanism 107 driven by the inverter motor 105.

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

  The first housing 103a is a member having a cylindrical shape with a bottom, and the 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) that guides the refrigerant in the discharge chamber 103A to the outside, and a first flange portion 103aa. The first flange portion 103aa is used when integrally fixing the first housing 103a, the second housing 103b, and the motor case 103c with the housing bolt 104, and is an end portion on the opening side of the first housing 103a. Is 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 portion 103ba extending radially outward from an end portion on the first housing 103a side. is there. The second housing 103b is arranged such that the flange portion 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 rotating shaft 119 is provided inside a first bearing 121. The first bearing 121 is provided with a suction passage 124 extending in the wall surface along the axis CE of the rotary shaft 119. Further, the second housing 103b is provided with a flange portion 103ba and a second flange portion 103bb used when integrally fixing the first housing 103a, the second housing 103b and the motor case 103c with the housing bolt 104. There is. The second flange portion 103bb is a member that extends outward in the radial direction from the flange portion 103ba.

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

  The box 103ca is opened outward in the radial direction of the motor case 103c, and the inverter unit 179 of the inverter motor 105 is housed inside. The case flange portion 103cb is used when integrally fixing the first housing 103a, the second housing 103b, and the motor case 103c using the housing bolt 104, and the radius from the end of the motor case 103c on the opening side. The member extends 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 portion 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 orbit 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. , Are provided.

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

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

  The capacitor 181 temporarily stores a current. The electronic element such as the power transistor 183 provided on the substrate 185 controls 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 so that heat generated from the power transistor 183 is released to the motor case 103c. The other substrate 185 is fixed at a position away from the motor case 103c. In other words, the substrates 185 are fixed in a laminated state. The terminal 187 supplies an alternating current controlled by the power transistor 183 or the like to the stator 115.

  It should be noted that the inverter motor 105 may be used as the electric drive unit as described above, or any other known motor may be used as the electric drive unit without any 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 133a and a spiral fixed side wrap 133b extending from the fixed side end plate 133a toward the orbiting scroll 135. The fixed scroll 133 is fixed to the bottom surface of the first housing 103a. The fixed side 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 135a and a spiral movable side wrap 135b extending from the movable side end plate 135a toward the fixed scroll 133. The orbiting scroll 135 is rotatably supported by the rotating shaft 119 and the rotation preventing portion 139. The orbiting scroll 135 is provided with a cylindrical boss 135c extending toward the rotary shaft 119 on a surface (also referred to as a bottom surface) of the movable side end plate 135a facing the rotary shaft 119. The rotative driving force of 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 cylindrical member extending from the inverter motor 105 toward the orbiting scroll 135. The rotary shaft 119 is rotatable with respect to the housing 103 on the basis of an axial center CE that extends in the horizontal direction (left-right direction in FIG. 7) by the first bearing 121 at the one end and the second bearing 123 at the other end. Supported by. As shown in FIG. 8, the rotary shaft 119 has a disc portion 119A, an eccentric pin 125, and a limit hole 126.

  The disk 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 arranged inside the penetrating portion 121a formed in the first bearing 121, the peripheral surface of which is supported by the bearing 122 fixed to the penetrating portion 121a, and the axial center of the disc bearing 119A. It is rotatably provided around the CE. The eccentric pin 125 is formed in a cylindrical shape that extends from the end surface 119Aa of the disc portion 119A along an eccentric LE that is eccentric with respect to the axis CE. The limit hole 126 is a hole that is recessed from the end surface 119Aa of the disk portion 119A, and is formed along another eccentricity LE 'that is biased with respect to the axis CE.

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

  In the bush 141, the eccentric pin 125 is inserted into a circular hole portion 141a formed in a tubular shape. The bush 141 has a contact end surface 141b that comes into contact with the end surface 119Aa of the disc portion 119A of the rotary shaft 119 by inserting the eccentric pin 125 into the circular hole portion 141a. Further, the bush 141 is inserted into the boss 135c of the orbiting scroll 135. For this reason, the bush 141 is formed in a circular outer shape so as to match 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 transfer the eccentric rotation of the bush 141 to the revolution of the orbiting scroll 135.

  The limit pin 142 is a cylindrical member that is arranged between the bush 141 and the disc portion 119A and that 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 141c formed in the bush 141, and the eccentric pin 125 is inserted into the circular hole portion 141a of the bush 141. It is provided so as to protrude from the contact end surface 141b along the eccentricity LE 'so as to be inserted into the. A gap is formed between the peripheral surfaces of the limit pins 142 while being inserted in the limit holes 126. Further, the limit pin 142 has a concave fitting groove 142a formed on the side surface of the portion to be 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 a columnar member having another cross-sectional shape, and is not particularly limited.

  The elastic portion 142b is fitted in the fitting groove 142a 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 when the limit pin 142 is inserted in the limit hole 126. It is a substantially cylindrical elastic member arranged. As a material for forming the elastic portion 142b, it is desirable to use a rubber that has compatibility with the refrigerant and the lubricating oil of the scroll compressor 101 and does not swell. Specific examples thereof include HNBR (hydrogenated nitrile rubber) and the like, but a rubber suitable for the refrigerant or lubricating oil used can be used.

  The elastic portion 142b is formed such that the outer peripheral surface has a diameter not smaller than the diameter of the limit hole 126, and the inner peripheral surface has a diameter not larger than the diameter of the limit pin 142. The elastic portion 142b is provided with a ridge-shaped convex portion that fits into the fitting groove 142a on the inner peripheral surface over the inner peripheral surface. The elastic portion 142 b has at least rigidity to support the own 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 orbitally driven. On the other hand, the rigidity of the elastic portion 142b is crushed and the limit pin 142 directly contacts the inner peripheral surface of the limit hole 126 when the orbiting scroll 135 is orbitally driven and the reaction force due to the centrifugal force and the compression of the refrigerant is working. It is suppressed to the extent that it does.

  As shown in FIG. 9, the relative positional relationship between the circular hole portion 141a and the limit pin 142 is such that when the bush assembly 137 is viewed from the circular plate portion 119A side (left side in FIGS. 7 and 8), the circular hole portion 141a is 2 The case where the limit pin 142 is arranged in the 8 o'clock direction can be exemplified as the case where the limit pin 142 is arranged in the time direction.

  The balance weight 143 is a member that adjusts the pressing force of the orbiting scroll 135 against the fixed scroll 133 and balances the force. As shown in FIGS. 8 and 9, the balance weight 143 is a brim-shaped member that extends in a semicircular shape from the circumferential surface of the bush 141 on the side of the disk portion 119A toward the outer side 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 141a is arranged in the 2 o'clock direction, and the balance weight 143 is It is provided 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 143A is formed in a ring shape, and its hole portion 143Aa 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 located 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 on a part of the outer periphery of the connecting portion 143A so that the weight becomes thicker in the direction away from the contact end surface 141b and overhangs.

  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 142b 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. Due to such combination, the bush assembly 137 is rotatable about the eccentric pin 125 as a rotation center within a range regulated by the limit pin 142 and the limit hole 126.

  When the orbiting scroll 135 is revolved, the compression chamber C formed between the orbiting scroll 135 and the fixed scroll 133 takes in and compresses the refrigerant flowing from the motor case 103c into the scroll compressor 101. Specifically, the compression chamber C takes in the refrigerant at the outer peripheral ends of the fixed scroll 133 and the orbiting scroll 135. The orbit of the orbiting scroll 135 causes the compression chamber C to have a smaller 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 holes 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 revolution and the compression reaction force of the refrigerant compressed by the compression chamber C act in the direction of expanding the revolution revolution radius. Due to these forces, the orbiting scroll 135 and the bush assembly 137 rotate about the eccentric pin 125, and the orbiting radius increases. Then, the limit pin 142 and the limit hole 126 approach while contacting each other while crushing the elastic portion 142b. By contacting the limit pin 142 and the limit hole 126, the rotation range of the bush assembly 137 and the orbiting scroll 135 around the eccentric pin 125 is restricted. The centrifugal force and the compression reaction force acting on the orbiting scroll 135 are large enough to crush the elastic portion 142b, and the magnitude of the force can be, for example, about several thousand N.

  Due to such an operation, for example, a liquid refrigerant (hereinafter referred to as a liquid refrigerant) is present in the compression chamber C, or a foreign matter is caught between the orbiting scroll 135 and the fixed scroll 133. In such a case, the orbiting scroll 135 has a small orbiting radius, and an escape passage for liquid refrigerant and foreign matter is formed. That is, due to the liquid compression reaction force generated when the liquid refrigerant is compressed and the resistance force generated when the foreign matter is bitten, the bushing assembly 137 together with the orbiting scroll 135 crushes the elastic portion 142b to center the eccentric pin 125. As a result, it rotates in the direction of reducing the revolution 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 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 orbiting radius of the orbiting scroll 135 disappears. . The orbiting scroll 135 rotationally moves around the eccentric pin 125 due to gravity acting vertically downward, and the limit pin 142 and the limit hole 126 are separated from each other. The elastic portion 142b that has been crushed between the limit pin 142 and the limit hole 126 due to centrifugal force or the like when the scroll compressor 101 is operating also causes the limit pin 142 and the limit hole 126 to move due to the force of returning from the crushed shape to the original shape. Separate. 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 exerts a crushing force due to the gravity acting on the orbiting scroll 135 and the bush assembly 137, but the magnitude thereof is about several N, which is smaller than the centrifugal force and the compression reaction force. Can be kept apart from the limit hole 126. Therefore, when the operation of the scroll compressor 101 is stopped, rattling noise generated by 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 is present 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 separates from a predetermined region on the inner peripheral surface of the limit hole 126 and comes into contact (collision) with a region on the opposite side, the shape of the elastic portion 142b is deformed to limit the limit pin 142 and the limit pin 142. The momentum at the time of contact with the hole 126 is reduced. Therefore, rattling noise generated when the limit pin 142 and the limit hole 126 contact each other when the liquid refrigerant is present in the compression chamber C is suppressed.

  Further, the rattling noise when the orbiting radius of the orbiting scroll 135 is not stable or when foreign matter is caught between the orbiting scroll 135 and the fixed scroll 133 is similarly suppressed by the action of the elastic portion 142b described above. To be done.

  The limit pin 142 and the limit hole 126 are not limited to the configuration in which the escape passage is formed between the orbiting scroll 135 and the fixed scroll 133. For example, although not clearly shown in the figure, the limit pin 142 and the limit hole 126 are not provided, and a gap 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 is not eccentric. It may be movable in the radial direction of 125, thereby forming an escape passage between the orbiting scroll 135 and the fixed scroll 133.

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

  The first arc 125a is in the 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 disc portion 119A of the rotary shaft 119 and is centered at the position of the eccentric LE. It is formed within the outer shape range of the rotary shaft 119 (here, the disc portion 119A) by the one radius Ra.

  The second arc 125b is in the range of P12-P11 in FIG. 6, and in a portion where the first radius Ra exceeds the outer edge 119Ab of the outer shape of the rotating shaft 119, the second arc 125b is less than or equal to the radius R forming the outer edge 119Ab of the rotating shaft 119. It is formed by a second radius Rb whose length is 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 rotary shaft 119 has an outer shape that is eccentric LE with a length exceeding a part of the outer edge 119Ab of the rotary shaft 119 (here, the disc portion 119A). The first arc 125a formed within the range of the outer shape of the rotating shaft 119 by the first radius Ra centering on the position of and the length equal to or less than the radius R forming the outer edge 119Ab at the portion where the first radius Ra exceeds the outer edge 119Ab. And a second arc 125b formed by a second radius Rb centered on the position of the axis CE.

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

  Moreover, the outer shape of the eccentric pin 125 is formed by the second radius Rb centered at the position of the axial center CE with a length equal to or shorter than the radius R forming the outer edge 119Ab in the portion where the first radius Ra exceeds the outer edge 119Ab. By having the two arcs 125b, the outer shape of the eccentric pin 125 is prevented from protruding from the outer edge 119Ab of the rotary 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 rotary shaft 119 requires time and labor. Although the eccentric pin 125 interferes with the insertion of the bearings 121 and 123, and the assembly is troublesome, such inconvenience can be eliminated.

In addition, 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 axial center 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 circular arc 125b is formed by a second radius Rb having a length equal to or shorter than the radius R forming the outer edge 119Ab of the rotary shaft 119 and centered on the position of the axial center CE, but when the second radius Rb is equal to or smaller than the radius R. The outer shape of the eccentric pin 125 is reduced in diameter. According to this scroll compressor 101, 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 125 is prevented from being thinned. You can 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 remarkably 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 due to the centrifugal force acting on the weight 143B from the connecting portion 143A as a starting point. Since this moment acts on the joint between the bush 141 and the connecting portion 143A, there is a problem that the connecting portion 143A is disengaged from the bush 141 or the position of the connecting portion 143A is displaced with respect to the bush 141.

  Therefore, in the present embodiment, in the bush assembly 137, the joining of the bush 141 and the balance weight 143 is devised.

  As shown in FIG. 8, in the scroll compressor 101 of the present embodiment, the connecting portion 143A is arranged so as to be displaced from the bush 141 in the longitudinal direction of the bush 141 (right side in FIG. 8), and A step portion 147 is formed between the contact end surface 141b of the bush 141, which is a surface facing the end surface 119Aa of the disc portion 119A, and the end surface 143Ab of the coupling portion 143A. The step portion 147 is formed by attaching the connecting portion 143A to the bush 141 so that the end surface 143Ab of the connecting portion 143A is slightly separated from the contact end surface 141b of the bush 141 from the end surface 119Aa of the disc portion 119A of the rotating shaft 119. The step 147 is provided with a joint 149 that joins the bush 141 and the connecting portion 143A. The joint portion 149 is formed on the end surface 143Ab of the connecting portion 143A and the side surface of the bush 141 at the step portion 147 so as not to project to the end surface 119Aa side of the disk portion 119A of the rotary shaft 119 beyond the contact end surface 141b of the bush 141. Has been formed. The joint 149 is formed by laser welding. The joining portion 149 is not limited to laser welding and may be formed by other welding.

  As described above, in the scroll compressor 101 of the present embodiment, the bush assembly 137 has the contact end surface 141b that is in contact with the end surface 119Aa of (the disc portion 119A of) the rotating shaft 119 by inserting the eccentric pin 125, and The bush 141 inserted into the cylindrical boss 135c provided on the bottom surface of the orbiting scroll 135, the connecting portion 143A arranged on the outer peripheral portion of the bush 141 near the contact end surface 141b, and the outer peripheral portion of the connecting portion 143A. A balance weight 143 having a weight 143B that is provided in a cantilever shape so as to partly project in a direction away from the contact end surface 141b, and a step portion 147 provided between the connecting portion 143A and the contact end surface 141b of the bush 141, The bush 141 and the connecting portion 143A provided on the step portion 147 are joined together. It was provided with a joint portion 149, a.

  According to this scroll compressor 101, the connecting portion 143A is used as a starting point due to the action of the centrifugal force of the weight 143B, which is provided in a cantilever manner in a part of the outer circumference of the connecting portion 143A in a direction away from the contact end surface 141b. The generated moment acts so as to rotate the weight 143B in the direction in which the contact end surface 141b is present, but at the stepped portion 147, this moment acts so as to bring the connecting portion 143A closer to the bush 141 side. Therefore, an excessive load is not applied to the joint portion 149 provided in the step portion 147, the rigidity of the joint between the bush 141 and the coupling portion 143A can be secured, and the coupling portion 143A is disengaged from the bush 141, This prevents the position of the connecting portion 143A from being displaced with respect to the bush 141.

  Moreover, since the joining portion 149 joining the bush 141 and the connecting portion 143A is provided in the step portion 147, it is possible to prevent the joining portion 149 from protruding from the contact end surface 141b of the bush 141 that comes into contact with 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 processing of the joint 149 for preventing the interference can be omitted. The weight 143B is provided in a cantilever manner so as to project from the connecting portion 143A in a direction away from the contact end surface 141b, and the step portion 147 is provided between the contact end surface 141b on the opposite side from which the weight 143B projects 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 bushing assembly 37 may have the joint portion 149 provided on the entire circumference in the circumferential direction of the bush 141, but as shown in FIG. It is preferable that the bushes 141 are provided at a plurality of positions (three positions in FIG. 9) in the circumferential direction. The circumferential direction of the bush 141 is a direction along the circumferential surface of the bush 141 with the center O of the bush 141 as a reference.

  According to this scroll compressor 101, when the joint portion 149 is formed by welding, the joint portion 149 is provided at a plurality of positions in the circumferential direction of the bush 141 rather than being provided at the entire circumferential direction of the bush 141. By doing so, thermal deformation of the bush 141 and the connecting portion 143A due to welding heat can be suppressed.

  Further, in the scroll compressor 101 of the present embodiment, in the bush assembly 137, when the joint portions 149 are provided at a plurality of positions in the circumferential direction of the bush 141, the joint portions 149 are evenly arranged in the circumferential direction of the bush 141. Is preferably provided. In FIG. 9, the joints 149 are provided at three locations in the circumferential direction of the bush 141, and they 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 portions 149 are evenly arranged in the circumferential direction of the bush 141, so that the heat of the bush 141 and the coupling portion 143A due to welding heat is generated. Even if deformation occurs, it is possible to equalize and suppress local deformation.

  Further, in the scroll compressor 101 of the present embodiment, in the bush assembly 137, when the joint portions 149 are provided at a plurality of positions in the circumferential direction of the bush 141, the joint portions 149 are provided near the weight 143B. It is preferable that a large number of them are arranged. When the joints 149 are evenly arranged in the circumferential direction of the bush 141, as shown in FIG. 9, in the configuration in which the joints 149 are provided at odd-numbered locations in the circumferential direction of the bush 141, the joints 149 are arranged. However, many are arranged near the weight 143B.

  According to the scroll compressor 101, the moment from the connecting portion 143A as a starting point acts in the vicinity of the weight 143B provided with the centrifugal force of the weight 143B. In the case of being provided at a plurality of positions in the direction, by arranging a large number of joints 149 near the weight 143B, the effect of ensuring the rigidity of the joint between the bush 141 and the connecting portion 143A can be obtained remarkably. be able to.

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

  According to this scroll compressor 101, the oil supply groove 151 is for supplying lubricating oil to the scroll compression mechanism 107, and when the joint portion 149 is formed by welding, the joint portion 149 corresponds to 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 lubricating oil can be smoothly supplied by the oil supply groove 151.

  Further, in the scroll compressor 101 of the present embodiment, in the bush assembly 137, the bush 141 is preferably made of a sintered material, and the balance weight 143 is preferably made of a cast iron material.

  According to the scroll compressor 101, since the bush 141 is a sliding member connected to the eccentric pin 125 and the boss 135c of the orbiting scroll 135, it is preferable that the bush 141 is made of a sintered material having a relatively high hardness. In addition, the balance weight 143 has a weight 143B that balances the dynamic imbalance generated by the unbalanced weight of the orbiting scroll 135, the boss 135c, the orbiting bearing 145, the bush assembly 137, etc. accompanying the orbiting movement of the orbiting scroll 135. Therefore, it is preferably formed of a relatively high density cast iron material.

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

  According to this scroll compressor 101, since the bush 141 and the connecting portion 143A of the balance weight 143 are fixed by shrink fitting or shrink fitting, the bush 141 and the connecting portion synergize with the provision of 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 the shrink fitting or shrink fitting is performed. The bush 141 and the connecting portion 143A are fitted to each other by means of, and then the joint portion 149 is formed by welding. In this way, by fitting the bush 141 and the connecting portion 143A in advance by shrink fitting or shrink fitting, the bush 141 and the connecting portion 143A can be welded to each other to form the joint 149 without displacement. .

  In the scroll compressor 101 of the present embodiment, the bush assembly 137 has the bush 141 rotatably provided 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 that restricts the range is provided, and the joint portion 149 is arranged away from the radial range of the part to which the limit pin 142 is attached (fitting hole 141c into which the limit pin 142 is fitted). Is preferred.

  According to this scroll compressor 101, when the joint 149 is formed by welding, the joint 149 is arranged away from the radial range of the portion to which the limit pin 142 is attached, so that the limit due to welding heat is generated. It is possible to suppress the thermal deformation of the part to which the pin 142 is attached, and to prevent the situation where the attachment of the limit pin 142 is obstructed.

  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 the configuration is not limited to this. Although not shown in the drawing, the limit pin 142 may be attached to the end surface 119Aa of the rotary 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, in the bush assembly 137, the bush 141 is rotatably provided with respect to the eccentric pin 125, and the limit pin 142 fixed to the end surface 119Aa of the rotary shaft 119 is inserted. It is preferable that the limit hole 126 that restricts the rotation range be provided, and that the joint portion 149 be arranged away from the radial range of the portion that forms the limit hole 126.

  According to this 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 forming the limit hole 126, so that the welding heat is generated. It is possible to suppress thermal deformation of the portion forming the limit hole 126, and it is possible to suppress a situation in which the accuracy of the rotation range regulated by the limit hole 126 is reduced.

  Further, in the scroll compressor 101 of the present embodiment, the maximum rotation speed of the rotary shaft 119 exceeds 145 rps.

  According to this scroll compressor 101, with the above-described configuration, it is possible to suppress the occurrence of bending of the eccentric pin 125, and also to secure the rigidity of the joint between the bush 141 and the connecting portion 143A in the bush assembly 137. Therefore, it is possible to realize the scroll compressor 101 in which the maximum rotation speed of the rotating shaft 119 exceeds 145 rps.

  The scroll fluid machine is not limited to the scroll compressors 1 and 101, and may be a scroll expander. Although not explicitly shown in the figure, a scroll expander, which is a scroll fluid machine, orbits a orbiting scroll that meshes with a fixed scroll by the compressed fluid to cause the fluid to expand and generate a rotational driving force on a rotating shaft. That is, the configurations of the eccentric pins 25 and 125 of the rotary shafts 19 and 119 and the configurations of the bush assemblies 37 and 137 of the scroll compression mechanisms 7 and 107 described above can be applied to a 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 25a, 125a First arc 25b, 125b Second arc 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 face 41c Bush side slide face 43,143 Balance weight 43A, 143A Connecting part 43Aa, 143Aa Hole part 43B, 143B Weight 47, 147 Step part 49, 149 Joint part 51, 151 Oil supply groove CE Shaft center LE Eccentric R radius Ra first radius Rb second radius ρ distance

Claims (9)

A fixed scroll fixed to the housing,
An orbiting scroll provided so as to be able to orbit while meshing with the fixed scroll,
A rotating shaft having an eccentric pin rotatably supported with respect to the housing and eccentric with respect to an axis;
A bush interposed between the eccentric pin and the orbiting scroll to transmit the rotational movement of the eccentric pin as the orbiting movement of the orbiting scroll;
In a scroll fluid machine including
The eccentric pin is
A first arc whose outer shape is formed within a range of the outer shape of the rotary shaft by a first radius Ra having a length exceeding a part of an outer edge of the rotary shaft and centered on the position of the eccentricity; In a portion where the first radius Ra exceeds the outer edge, a second arc formed by a second radius Rb having a length equal to or shorter than the radius R forming the outer edge and centered on the position of the axis, the first arc and the second arc. and one pin side slide surface to slidably move said bush is arranged between the second circular arc, was perforated,
In the inner shape of the hole into which the eccentric pin is inserted, the bush has one bush-side slide surface facing the pin-side slide surface, a portion that matches the first arc, and a second arc that is larger than the second arc. A portion formed to have a large diameter, and the eccentric radial opposite side of the bush side slide surface is provided so as to be able to contact the eccentric pin together with the bush side slide surface.
A scroll fluid machine characterized by the above. The first radius Ra, the second radius Rb, the radius R, and the distance ρ between the axial center position and the eccentric position are (Ra ² + ρ ² ) ^1/2 ≦ Rb ≦ R The scroll fluid machine according to claim 1, wherein the relationship is satisfied. The bush, which has a contact end surface into which the eccentric pin is inserted and contacts the end surface of the rotating shaft, and which is inserted into a cylindrical boss provided on the bottom surface of the orbiting scroll;
A balance weight having an outer peripheral portion of the bush, which is arranged in the vicinity of the contact end surface, and a weight which is provided in a cantilever shape in a part of the outer periphery of the connecting portion so as to project in a direction away from the contact end surface. When,
A step portion provided between the connecting portion and the contact end surface of the bush,
A joint portion provided at the step portion and joining the bush and the connecting portion,
The scroll fluid machine according to claim 1 or 2, further comprising a bush assembly including the.   The scroll fluid machine according to claim 3, wherein the bush assembly has the joint portions provided at a plurality of positions in the circumferential direction of the bush.   The scroll fluid machine according to claim 4, wherein in the bush assembly, the joint portions are evenly arranged in a circumferential direction of the bush.   The scroll fluid machine according to claim 4 or 5, wherein the bushing assembly has a large number of the joints in the vicinity of where the weight is provided. Said bushing assembly, said bushing is formed by sintered material, a scroll fluid machine according to any one of claims 3-6, wherein the balance weight is characterized in that it is formed by cast iron. The bushing assembly includes a scroll fluid machine according to any one of claims 3-7, characterized in that said connecting portion of said bushing and said balance weight is fixed by shrink fit or interference fit. Scroll fluid machine according to any one of claims 1-8 for the maximum rotational speed of the rotating shaft is equal to or more than 145Rps.

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