Scroll fluid machinery

Abstract

Lubricating oil is well supplied to the bearing supporting the eccentric bushing. The scroll compressor (100) has a fixed scroll (122) fixed to the housing (140), an orbiting scroll (124) that orbits relative to the fixed scroll, and a conversion mechanism (300) that converts the rotational motion of the drive shaft (166) and the orbiting motion of the orbiting scroll. The conversion mechanism includes: an eccentric shaft (260) that is arranged on the end face of the drive shaft and is eccentric relative to the drive shaft; an eccentric bushing (270) that has a through hole (271) for the eccentric shaft to be embedded; a bearing (280) that is pressed into a sleeve portion (250) formed on the orbiting scroll and supports the outer peripheral surface (272) of the eccentric bushing, and a lubricating oil supply flow path (350) for supplying lubricating oil to the bearing is formed through the eccentric bushing. The outflow port (356) of the lubricating oil supply flow path is arranged on the outer peripheral surface (272) of the eccentric bushing.

Description

Technical Field

[0001] The present invention relates to a scroll type fluid machine such as a scroll type compressor and a scroll type expander. Background Art

[0002] Patent Document 1 discloses a scroll compressor as an example of a scroll fluid machine. In this scroll compressor, a drive shaft is connected to an orbiting scroll via a crank mechanism. The crank mechanism comprises a sleeve portion formed on the back-pressure chamber-side end surface of the bottom plate of the orbiting scroll, and an eccentric bushing eccentrically mounted on a crank pin provided at the end of the drive shaft. The eccentric bushing is rotatably supported on the inner circumferential surface of the sleeve portion via a bearing.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2019-015188 Summary of the Invention

[0006] Technical problem to be solved by the invention

[0007] However, the bearings are lubricated by the scattering of lubricating oil from a back pressure chamber formed on the back side of the orbiting scroll. Therefore, there is a possibility that the lubricating oil may not be supplied sufficiently to the bearings.

[0008] Therefore, an object of the present invention is to satisfactorily supply lubricating oil to a bearing that supports an eccentric bushing.

[0009] Technical solutions used to solve technical problems

[0010] According to one aspect of the present invention, a scroll-type fluid machinery has a rotating main shaft arranged to rotate freely within a housing, a fixed scroll fixed to the housing, an orbiting scroll that performs an orbiting motion relative to the fixed scroll, and a conversion mechanism that converts the rotational motion of the rotating main shaft and the orbiting motion of the orbiting scroll into each other. The conversion mechanism includes: an eccentric shaft, which is arranged on the end face of the rotating main shaft and is eccentric relative to the rotating main shaft; an eccentric bushing, which has a through hole for the eccentric shaft to be embedded; and a bearing, which is pressed into a sleeve portion formed in the orbiting scroll to support the outer peripheral surface of the eccentric bushing, and a lubricating oil supply flow path is formed through the eccentric bushing, and the lubricating oil supply flow path is used to supply lubricating oil to the bearing. Here, the outflow port of the lubricating oil supply flow path is arranged on the outer peripheral surface of the eccentric bushing.

[0011] Effects of the Invention

[0012] According to one aspect of the present invention, the outlet of the lubricating oil supply passage is disposed on the outer peripheral surface of the eccentric bushing. Thus, lubricating oil can be directly supplied to the bearing from the outlet of the lubricating oil supply passage, thereby enabling lubricating oil to be well supplied to the bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a longitudinal sectional view of the scroll compressor according to the first embodiment of the present invention.

[0014] Figure 2 This is a block diagram illustrating the flows of the gas refrigerant and the lubricating oil according to the first embodiment.

[0015] Figure 3 This is an enlarged cross-sectional view of the conversion mechanism according to the first embodiment. Figure 4 This is a perspective view of the eccentric bushing according to the first embodiment.

[0016] Figure 5 This is a cross-sectional view of the eccentric bushing according to the first embodiment.

[0017] Figure 6 It is an enlarged cross-sectional view of a conversion mechanism according to a second embodiment of the present invention. DETAILED DESCRIPTION

[0018] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The scroll fluid machine of the present invention will be described herein as a scroll compressor. However, it goes without saying that the present invention can also be applied to a scroll expander.

[0019] Figure 1 It is a longitudinal sectional view of the scroll compressor 100 according to the first embodiment of the present invention.

[0020] The scroll compressor 100 is installed in the refrigerant circuit of a vehicle air conditioning system, for example, and compresses and discharges gaseous refrigerant (fluid) drawn in from the low-pressure side of the refrigerant circuit. The scroll compressor 100 includes a scroll unit 120; a housing 140 that houses a suction chamber H1 and a discharge chamber H2 for the gaseous refrigerant; an electric motor 160 that drives the scroll unit 120; and an inverter 180 that drives and controls the electric motor 160. Alternatively, the scroll unit 120 can be driven by, for example, engine output instead of the electric motor 160. Furthermore, the inverter 180 does not need to be installed in the scroll compressor 100.

[0021] The scroll unit 120 includes a fixed scroll 122 and an orbiting scroll (orbiting scroll) 124 that mesh with each other. The fixed scroll 122 includes: a circular plate-shaped bottom plate 122A; and a gradually opening (vortex-shaped) surround member 122B that stands upright from one side of the bottom plate 122A. The orbiting scroll 124, like the fixed scroll 122, includes: a circular plate-shaped bottom plate 124A; and a gradually opening surround member 124B that stands upright from one side of the bottom plate 124A. Here, the so-called circular plate-shaped may be such that it can be identified as a circular plate from the appearance, or may have protrusions, recesses, grooves, etc. formed on the outer surface (the same shall apply to the shape below).

[0022] The fixed scroll 122 and the orbiting scroll 124 are arranged so that their wraps 122B and 124B mesh with each other. Specifically, the front end of the wrap 122B of the fixed scroll 122 contacts one surface of the bottom plate 124A of the orbiting scroll 124, while the front end of the wrap 124B of the orbiting scroll 124 contacts one surface of the bottom plate 122A of the fixed scroll 122. Chip-shaped seals (not shown) are attached to the front ends of the wraps 122B and 124B, respectively.

[0023] Furthermore, the fixed scroll 122 and the orbiting scroll 124 are arranged so that, with their wraps 122B and 124B angularly offset from each other in the circumferential direction, their side walls partially contact each other. Consequently, a crescent-shaped, enclosed space serving as a compression chamber H3 is formed between the wrap 122B of the fixed scroll 122 and the wrap 124B of the orbiting scroll 124.

[0024] The orbiting scroll 124 orbits relative to the fixed scroll 122. While its rotation is prevented, the orbiting scroll 124 is configured to orbit around the axis of the fixed scroll 122 via a conversion mechanism 300 (described later). Consequently, the scroll unit 120 moves the compression chamber H3, defined by the surround 122B of the fixed scroll 122 and the surround 124B of the orbiting scroll 124, to the center, gradually reducing its volume. As a result, the scroll unit 120 compresses the gas refrigerant drawn into the compression chamber H3 from the outer ends of the surrounds 122B and 124B.

[0025] The housing 140 includes a front housing 142 that houses the electric motor 160 and the inverter 180, an intermediate housing 144 that houses the scroll unit 120, a rear housing 146, and an inverter cover 148. The front housing 142, the intermediate housing 144, the rear housing 146, and the inverter cover 148 are integrally fastened together using fasteners (not shown) such as bolts and washers, thereby forming the housing 140 of the scroll compressor 100.

[0026] The front housing 142 has a cylindrical peripheral wall portion 142A and a thin plate-shaped partition wall portion 142B. The interior space of the front housing 142 is divided by the partition wall portion 142B into a space for accommodating the electric motor 160 and a space for accommodating the inverter 180. The opening on one end of the peripheral wall portion 142A, i.e., the space for accommodating the inverter 180, is blocked by the inverter cover 148. Furthermore, the opening on the other end of the peripheral wall portion 142A, i.e., the space for accommodating the electric motor 160, is blocked by the intermediate housing 144. A cylindrical support portion 142B1 is provided in the partition wall portion 142B, projecting toward the other end of the peripheral wall portion 142A. This support portion 142B1 rotatably supports one end of a drive shaft 166, described later, at its radial center. The drive shaft 166 is an example of a "rotating spindle" of the present invention and is rotatably disposed within the housing 140.

[0027] In addition, the suction chamber H1 for the gas refrigerant is defined by the peripheral wall portion 142A of the front housing 142, the partition wall portion 142B, and the intermediate housing 144. The gas refrigerant is introduced into the suction chamber H1 from the low-pressure side of the refrigerant circuit via the suction port P1 formed in the peripheral wall portion 142A. In addition, in the suction chamber H1, the gas refrigerant circulates around the electric motor 160 and can cool the electric motor 160, and a suction chamber H1 is formed that connects the space on one side of the electric motor 160 with the space on the other side. An appropriate amount of lubricating oil is stored in the suction chamber H1 for lubricating sliding parts such as the drive shaft 166 that is driven to rotate. Therefore, in the suction chamber H1, the gas refrigerant flows as a mixed fluid with the lubricating oil.

[0028] The intermediate housing 144 is in the shape of a bottomed cylinder that is open on the side opposite to the fastening side of the front housing 142, and can accommodate the scroll unit 120 inside. The intermediate housing 144 has a cylindrical portion 144A and a bottom wall portion 144B on one end side thereof. The scroll unit 120 is accommodated in the space demarcated by the cylindrical portion 144A and the bottom wall portion 144B. A fitting portion 144A1 is formed on the other end side of the cylindrical portion 144A, and the fitting portion 144A1 is fitted with the fixed scroll 122. Therefore, the opening of the intermediate housing 144 is blocked by the fixed scroll 122. In addition, the bottom wall portion 144B is formed in such a manner that its radial center portion bulges toward the electric motor 160. A through hole for allowing the other end portion of the drive shaft 166 to pass through is formed in the radial center portion of the raised portion 144B1 of the bottom wall portion 144B. Furthermore, a fitting portion is formed on the scroll unit 120 side of the raised portion 144B1 , into which a bearing 200 rotatably supports the other end portion of the drive shaft 166 is fitted.

[0029] A thin, annular thrust plate 210 is disposed between the bottom wall 144B of the intermediate housing 144 and the bottom plate 124A of the orbiting scroll 124. The outer periphery of the bottom wall 144B receives thrust from the orbiting scroll 124 via the thrust plate 210. Seal members 220 are embedded in the areas of the bottom wall 144B and the bottom plate 124A that contact the thrust plate 210.

[0030] Furthermore, a back-pressure chamber H4 is formed between the end surface of the bottom plate 124A on the electric motor 160 side and the bottom wall portion 144B—that is, between the end surface of the orbiting scroll 124 opposite the fixed scroll 122 and the intermediate housing 144. A refrigerant inlet passage L1 is formed in the intermediate housing 144. This refrigerant inlet passage L1 introduces gaseous refrigerant from the suction chamber H1 into a space H5 near the outer ends of the surrounds 122B and 124B of the scroll unit 120. Because the refrigerant inlet passage L1 connects space H5 with the suction chamber H1, the pressure in space H5 is equal to the pressure in the suction chamber H1 (suction pressure Ps).

[0031] The rear housing 146 is fastened to one end of the fitting portion 144A1 of the cylindrical portion 144A of the intermediate housing 144 via fasteners. Consequently, the bottom plate 122A of the fixed scroll 122 is clamped between the fitting portion 144A1 and the rear housing 146 and secured. In other words, the fixed scroll 122 is secured to the housing 140. The rear housing 146, on the side fastened to the intermediate housing 144, has an open, bottomed cylindrical shape and includes a cylindrical portion 146A and a bottom wall portion 146B at the other end of the cylindrical portion 146A.

[0032] The cylindrical portion 146A and bottom wall portion 146B of the rear housing 146, along with the bottom plate 122A of the fixed scroll 122, define a discharge chamber H2 for the gas refrigerant. A discharge passage (discharge hole) L2 for the gas refrigerant is formed in the center of the bottom plate 122A. A check valve 230, such as a needle valve, is attached to the discharge passage L2 to restrict the flow of the gas refrigerant from the discharge chamber H2 to the scroll unit 120. In the discharge chamber H2, the gas refrigerant compressed in the compression chamber H3 of the scroll unit 120 is discharged through the discharge passage L2 and the check valve 230.

[0033] Although not shown, the rear housing 146 is equipped with an oil separator that separates lubricating oil from the refrigerant gas in the discharge chamber H2. The refrigerant gas from which the lubricating oil has been separated by the oil separator is discharged to the high-pressure side of the refrigerant circuit via a discharge port P2 formed in the bottom wall portion 146B of the rear housing 146. Meanwhile, the lubricating oil separated by the oil separator is supplied to the back-pressure chamber H4 via a back-pressure supply passage L3, described later.

[0034] The electric motor 160 is constituted by, for example, a three-phase AC motor and includes a rotor 162 and a stator core unit 164 disposed radially outward of the rotor 162. Furthermore, a DC current, for example, from an onboard battery (not shown) is converted into an AC current by an inverter 180 and supplied to the stator core unit 164 of the electric motor 160.

[0035] The rotor 162 is rotatably supported on the radial inner side of the stator core unit 164 via a drive shaft 166 that is pressed into an axial hole formed in the radial center of the rotor 162. One end of the drive shaft 166 is rotatably supported on the support portion 142B1 of the front housing 142 via a sliding bearing 240. The other end of the drive shaft 166 passes through a through hole formed in the intermediate housing 144 and is rotatably supported by a bearing 200. If a magnetic field is generated in the stator core unit 164 by power supply from the inverter 180, a rotational force will act on the rotor 162, and the drive shaft 166 will be driven to rotate. The other end of the drive shaft 166 is connected to the orbiting scroll 124 via a conversion mechanism 300.

[0036] The conversion mechanism 300 has the function of converting the rotational motion of the aforementioned rotating main shaft (the driving shaft 166 in this embodiment) and the orbiting motion of the orbiting scroll 124. The details of the conversion mechanism 300 will be described later. Figures 3 to 5 In this embodiment, the orbiting scroll 124 is prevented from rotating and is able to revolve around the axis of the fixed scroll 122 via the conversion mechanism 300. Furthermore, a balancing weight 290 is attached to the other end of the drive shaft 166 to overcome the centrifugal force of the orbiting scroll 124.

[0037] Figure 2 This is a block diagram for explaining the flows of gas refrigerant and lubricating oil in the scroll compressor 100 .

[0038] like Figure 1 as well as Figure 2 As shown, low-temperature, low-pressure gas refrigerant from the low-pressure side of the refrigerant circuit is introduced into the suction chamber H1 via the suction port P1. It is then directed through the refrigerant inlet passage L1 to the space H5 near the outer end of the scroll unit 120. The gas refrigerant in space H5 is then drawn into the compression chamber H3 of the scroll unit 120 and compressed. The gas refrigerant compressed in the compression chamber H3 is then discharged into the discharge chamber H2 via the discharge passage L2 and the check valve 230, and then discharged to the high-pressure side of the refrigerant circuit via the discharge port P2. In this manner, the scroll unit 120 is configured such that the gas refrigerant flowing in through the suction chamber H1 is compressed by the compression chamber H3 and discharged through the discharge chamber H2.

[0039] Here, if Figure 1 As shown, the scroll compressor 100 further includes a backpressure control valve 400 that controls the backpressure Pm in the backpressure chamber H4. The backpressure control valve 400 is a mechanical (autonomous) pressure regulating valve that operates based on the pressure difference between the discharge pressure Pd of the discharge chamber H2 and the backpressure Pm in the backpressure chamber H4, automatically adjusting its valve opening to bring the backpressure Pm in the backpressure chamber H4 closer to the target backpressure Pc. The backpressure control valve 400 is housed in a housing chamber 146C, which is formed in the bottom wall portion 146B of the rear housing 146 so as to extend from the outer peripheral surface of the bottom wall portion 146B in a direction perpendicular to the central axis of the drive shaft 166 of the electric motor 160.

[0040] Scroll compressor 100 Figure 1 as well as Figure 2 In addition to the refrigerant introduction passage L1 and the discharge passage L2 , the refrigerant system further includes a back pressure supply passage L3 , a pressure relief passage L4 , and a suction pressure sensing passage L5 .

[0041] A backpressure supply passage L3 is formed in the rear housing 146 and the intermediate housing 144 so as to communicate between the discharge chamber H2 and the backpressure chamber H4. The backpressure supply passage L3 in the rear housing 146 passes through the accommodation chamber 146C that houses the backpressure control valve 400. Furthermore, lubricating oil separated from the gas refrigerant in the discharge chamber H2 by the oil separator is directed to the backpressure chamber H4 via the backpressure control valve 400 and the backpressure supply passage L3 to lubricate the various sliding parts and increase the backpressure Pm in the backpressure chamber H4.

[0042] Back-pressure control valve 400 is positioned midway along back-pressure supply passage L3, forming a portion of it. Therefore, lubricating oil separated from the gaseous refrigerant in discharge chamber H2 is appropriately decompressed by back-pressure control valve 400 and supplied to back-pressure chamber H4 via back-pressure supply passage L3, located downstream of the valve. Specifically, by adjusting the opening of back-pressure supply passage L3, which is connected to the inlet (upstream) of back-pressure chamber H4, back-pressure control valve 400 increases or decreases the flow rate of lubricating oil flowing into back-pressure chamber H4, thereby regulating back-pressure Pm.

[0043] The pressure relief passage L4 is formed to extend through the drive shaft 166 in the axial direction, connecting the backpressure chamber H4 with the suction chamber H1. An orifice OL is provided midway through the pressure relief passage L4, for example, at the end of the drive shaft 166 on the suction chamber H1 side. Therefore, the lubricating oil in the backpressure chamber H4 is restricted in flow by the orifice OL and flows back into the suction chamber H1.

[0044] The suction pressure sensing passage L5 connects the space H5 near the outer end of the scroll unit 120 with the accommodation chamber 146C, enabling sensing of the suction pressure Ps in the suction chamber H1 in the backpressure control valve 400. Specifically, the suction pressure sensing passage L5 is formed in the bottom plate 122A of the fixed scroll 122 and the rear housing 146. While the suction pressure sensing passage L5 indirectly senses the suction pressure Ps in the suction chamber H1 via the space H5, it can also directly sense the suction pressure Ps in the suction chamber H1.

[0045] Here, a back-pressure chamber H4 (a mechanical chamber housing orbiting drive elements such as the drive shaft 166) is formed on the back side of the orbiting scroll 124 (i.e., the end surface of the orbiting scroll 124 opposite the fixed scroll 122). The back-pressure chamber H4 generates a back-pressure Pm that presses the orbiting scroll 124 toward the fixed scroll 122. Therefore, the back-pressure Pm in the back-pressure chamber H4 presses the orbiting scroll 124 toward the fixed scroll 122. During the compression operation of scroll unit 120, if the resultant force of back pressure Pm acting on the end surface of bottom plate 124A on the back pressure chamber H4 side of orbiting scroll 124 is too low compared to the compression reaction force acting on the end surface of compression chamber H3 on bottom plate 124A, resulting in a back pressure deficiency, a gap will form between the front end of orbiting scroll 124B's surround 124B and bottom plate 122A of fixed scroll 122, and a gap will also form between bottom plate 124A of orbiting scroll 124 and the front end of surround 122B of fixed scroll 122, thereby reducing the volumetric efficiency of the compressor. When back pressure Pm is less than target back pressure Pc, back pressure control valve 400 increases back pressure Pm and approaches target back pressure Pc to avoid a back pressure deficiency.

[0046] On the other hand, when the resultant force generated by the back pressure Pm in the back pressure chamber H4 is too high compared to the compression reaction force, that is, when the back pressure becomes excessive, the friction between the fixed scroll 122 and the orbiting scroll 124 increases, thereby reducing the mechanical efficiency of the compressor. When the back pressure Pm exceeds the target back pressure Pc, the back pressure control valve 400 reduces the back pressure Pm and approaches the target back pressure Pc to avoid the excessive back pressure.

[0047] Then, except Figure 1 In addition, also use Figures 3 to 5 The details of the conversion mechanism 300 will be described. Figure 3 It is an enlarged cross-sectional view of the conversion mechanism 300 . Figure 4 It is a perspective view of the eccentric bushing 270 . Figure 5 It is a cross-sectional view of the eccentric bushing 270 .

[0048] The conversion mechanism 300 includes an eccentric shaft (crank pin) 260, an eccentric bushing 270, and a bearing 280. The eccentric shaft 260 is disposed on the other end surface of the drive shaft 166 and is eccentric (offset) relative to the drive shaft 166. The eccentric bushing 270 is cylindrical and has a through hole 271, eccentric from its center axis BS, into which the eccentric shaft 260 is inserted. Therefore, the eccentric bushing 270 is attached to the eccentric shaft 260 in an eccentric state via the through hole 271.

[0049] The bearing 280 is pressed into the cylindrical sleeve portion 250 protruding from the end surface of the back pressure chamber H4 on the bottom plate 124A of the orbiting scroll 124, and supports the outer peripheral surface 272 of the eccentric bushing 270. In this embodiment, a sliding bearing is used as the bearing 280. Therefore, the eccentric bushing 270 is rotatably supported on the inner peripheral surface of the sleeve portion 250 via the bearing 280. In this way, the orbiting scroll 124 can revolve around the axis of the fixed scroll 122 via the conversion mechanism 300 while its rotation is prevented.

[0050] A lubricating oil supply passage 350 is formed through the eccentric bushing 270 to supply lubricating oil to the bearing 280. The lubricating oil supply passage 350 includes an axial passage portion 351 extending in the axial direction of the eccentric bushing 270 and a radial passage portion 352 extending in the radial direction of the eccentric bushing 270.

[0051] The axial flow path portion 351 extends substantially parallel to the center axis BS of the eccentric bushing 270 and the center axis RS of the drive shaft 166, and penetrates the eccentric bushing 270. The radial flow path portion 352 branches from the middle of the axial flow path portion 351 and extends radially in the eccentric bushing 270 to the outer peripheral surface 272 of the eccentric bushing 270.

[0052] A recessed portion 273 extending radially along the eccentric bushing 270 is formed on the end surface of the eccentric bushing 270 adjacent to the other end surface of the drive shaft 166. An opening at one end of the axial flow path portion 351 is located at the bottom surface of the recessed portion 273. This opening functions as an inlet 355 for the lubricating oil supply flow path 350. In other words, the axial flow path portion 351 includes the inlet 355 for the lubricating oil supply flow path 350.

[0053] An opening at one end of the radial flow path portion 352 on the outer circumferential surface 272 of the eccentric bushing 270 functions as an outlet 356 of the lubricating oil supply path 350. Specifically, the radial flow path portion 352 includes the outlet 356 of the lubricating oil supply path 350. The outlet 356 of the lubricating oil supply path 350 faces the inner circumferential surface (support surface) 281 of the bearing 280. Furthermore, the outlet 356 of the lubricating oil supply path 350 is preferably positioned so as to face the axial center of the inner circumferential surface 281 of the bearing 280.

[0054] like Figure 5 As shown, in this embodiment, when the eccentric bushing 270 is divided into a first region T1 and a second region T2 by a first imaginary plane PL1 including the center axis RS of the drive shaft 166, the center axis BS of the eccentric bushing 270, the lubricating oil supply flow path 350, and the through hole 271 are located within the first region T1. The first imaginary plane PL1 is an imaginary plane orthogonal to a second imaginary plane PL2 including both the center axis RS of the drive shaft 166 and the center axis BS of the eccentric bushing 270.

[0055] In this embodiment, when the distance between the first imaginary plane PL1 and the center axis BS of the eccentric bushing 270 is N1, and the distance between the first imaginary plane PL1 and the center axis WS of the axial flow path portion 351 is N2, the relationship N1 < N2 is satisfied. That is, when viewed from the first imaginary plane PL1, the center axis WS of the axial flow path portion 351 is farther from the center axis BS of the eccentric bushing 270. Furthermore, when viewed from the first imaginary plane PL1, the lubricating oil supply flow path 350 is farther from the center axis BS of the eccentric bushing 270.

[0056] In this embodiment, if the distance between the center axis RS of the drive shaft 166 and the center axis BS of the eccentric bushing 270 is N3, and the distance between the center axis RS of the drive shaft 166 and the center axis WS of the axial flow path portion 351 is N4, then the relationship N3 < N4 is satisfied. That is, when viewed from the center axis RS of the drive shaft 166, the center axis WS of the axial flow path portion 351 is farther from the center axis BS of the eccentric bushing 270. Furthermore, when viewed from the center axis RS of the drive shaft 166, the lubricating oil supply flow path 350 is farther from the center axis BS of the eccentric bushing 270.

[0057] Here, refer to Figure 1 as well as Figures 3 to 5 Supply of lubricating oil to bearing 280 will be described.

[0058] A portion of the lubricating oil in the backpressure chamber H4 flows through the recessed portion 273 of the eccentric bushing 270 from the inlet 355 into the axial flow path portion 351. Furthermore, due to the centrifugal force generated by the rotation of the drive shaft 166 about the central axis RS of the drive shaft 166, most of the lubricating oil in the axial flow path portion 351 flows into the radial flow path portion 352 and is supplied from the outlet 356 to the inner circumferential surface 281 of the bearing 280. In order to fully utilize the aforementioned centrifugal force, the layout of the lubricating oil supply flow path 350 is adopted in this embodiment.

[0059] According to this embodiment, a scroll compressor 100, an example of a scroll-type fluid machine, includes a rotatable drive shaft 166 (rotating main shaft) within a housing 140; a fixed scroll 122 fixed to the housing 140; an orbiting scroll 124 orbiting relative to the fixed scroll 122; and a conversion mechanism 300 for converting the rotational motion of the drive shaft 166 (rotating main shaft) into the orbiting motion of the orbiting scroll 124. The conversion mechanism 300 includes an eccentric shaft 260 disposed on an end surface of the drive shaft 166 (rotating main shaft) and eccentric relative to the drive shaft 166 (rotating main shaft); an eccentric bushing 270 having a through hole 271 into which the eccentric shaft 260 is inserted; and a bearing 280 press-fitted into a boss portion 250 formed in the orbiting scroll 124 and supporting an outer peripheral surface 272 of the eccentric bushing 270. A lubricating oil supply passage 350 is formed through the eccentric bushing 270 to supply lubricating oil to the bearing 280. An outlet 356 of the lubricating oil supply passage 350 is disposed on the outer peripheral surface 272 of the eccentric bushing 270. Thus, lubricating oil can be directly supplied to the bearing 280 from the outlet 356 of the lubricating oil supply passage 350, thereby ensuring good lubricating oil supply to the bearing 280.

[0060] Furthermore, according to the present embodiment, the outflow port 356 of the lubricating oil supply flow path 350 faces the inner peripheral surface 281 of the bearing 280 . This allows the lubricating oil to be well supplied to the inner peripheral surface 281 of the bearing 280 .

[0061] Furthermore, according to this embodiment, the lubricating oil supply passage 350 includes an axial flow path portion 351 extending in the axial direction of the eccentric bushing 270 and a radial flow path portion 352 extending in the radial direction of the eccentric bushing 270. The axial flow path portion 351 has an inlet 355 for the lubricating oil supply passage 350. The radial flow path portion 352 has an outlet 356 for the lubricating oil supply passage 350. This facilitates the formation of the lubricating oil supply passage 350.

[0062] Furthermore, according to this embodiment, when viewed from the center axis RS of the drive shaft 166 (rotating main shaft), the lubricating oil supply passage 350 is further away from the center axis BS of the eccentric bushing 270. This allows the centrifugal force generated by the rotation of the drive shaft 166 to be used to actively supply lubricating oil to the bearing 280.

[0063] Furthermore, according to this embodiment, when the eccentric bushing 270 is divided into a first region T1 and a second region T2 by a first imaginary plane PL1 including the center axis RS of the drive shaft 166 (rotational main shaft), the center axis BS of the eccentric bushing 270, the lubricating oil supply passage 350, and the through-hole 271 are located within the first region T1. When viewed from the first imaginary plane PL1, the lubricating oil supply passage 350 is further away from the center axis BS of the eccentric bushing 270. This allows the centrifugal force generated by the rotation of the drive shaft 166 to be actively utilized to supply lubricating oil to the bearing 280.

[0064] Furthermore, according to this embodiment, the scroll compressor 100, an example of a scroll-type fluid machine, further includes a back-pressure chamber H4 formed on the back side of the orbiting scroll 124. This back-pressure chamber H4 generates back pressure that presses the orbiting scroll 124 toward the fixed scroll 122. The inlet 355 of the lubricating oil supply passage 350 communicates with the back-pressure chamber H4. Therefore, the lubricating oil in the back-pressure chamber H4 can be smoothly supplied to the bearing 280.

[0065] Furthermore, according to this embodiment, the inlet 355 of the lubricating oil supply flow path 350 is arranged in the recess 273 formed on the end surface of the eccentric bushing 270. This allows the lubricating oil from the back pressure chamber H4 to be smoothly introduced into the lubricating oil supply flow path 350.

[0066] Furthermore, according to this embodiment, a sliding bearing is used as the bearing 280. Thus, the eccentric bushing 270 can be rotatably supported with a simple structure.

[0067] Next, use Figure 6 A second embodiment of the present invention will be described.

[0068] Figure 6 It is an enlarged cross-sectional view of the conversion mechanism 300 according to this embodiment.

[0069] Points different from the aforementioned first embodiment will be described.

[0070] A balancing weight (balance weight) 290' is integrally provided with the eccentric bushing 270. The balancing weight 290' is disposed on the side opposite the through-hole 271, sandwiching the center axis RS of the drive shaft 166. The eccentric bushing 270, which is integrally provided with the balancing weight 290', preferably also includes a lubricating oil supply passage 350, similar to that described above.

[0071] Furthermore, in the aforementioned first and second embodiments, the balancing weights 290 and 290 ′ may be omitted.

[0072] In the aforementioned first and second embodiments, the case where the scroll fluid machinery of the present invention is a scroll compressor is described, but it goes without saying that the present invention can also be applied to a scroll expander. When applied to a scroll expander, the scroll expander can be constructed, for example, by being installed in the refrigerant circuit of a vehicle steam cycle device, and expanding the refrigerant introduced from the refrigerant circuit to generate power (recovering power from the refrigerant). In addition, when applied to a scroll expander, the aforementioned drive shaft 166 becomes an output shaft. That is, if the scroll fluid machinery of the present invention is a scroll compressor, the "rotating main shaft" of the present invention functions as a drive shaft, and if the scroll fluid machinery of the present invention is a scroll expander, the "rotating main shaft" of the present invention functions as an output shaft.

[0073] While preferred embodiments of the present invention have been described above, the present invention is not limited to the aforementioned embodiments, and it is natural that further modifications and the like are possible based on the technical concept of the present invention.

[0074] (Explanation of Symbols)

[0075] 100 scroll compressors (scroll fluid machinery);

[0076] 122 fixed scroll;

[0077] 124 vortex disk;

[0078] 140 shell;

[0079] 166 driving shaft (rotating spindle);

[0080] 250 sleeve department;

[0081] 260 eccentric shaft;

[0082] 270 eccentric bushing;

[0083] 271 through-holes;

[0084] 272 outer peripheral surface;

[0085] 273 concavity;

[0086] 280 bearings;

[0087] 290, 290' balanced counterweight;

[0088] 281 inner circumference;

[0089] 300 conversion mechanism;

[0090] 350 lubricating oil supply flow path;

[0091] 351 axial flow path portion;

[0092] 352 radial flow path part;

[0093] 355 inlet;

[0094] 356 outflow;

[0095] BS, RS, WS center axis;

[0096] H4 back pressure chamber;

[0097] PL1 first imaginary plane;

[0098] PL2 second imaginary plane;

[0099] T1 first area;

[0100] T2 second area.

Claims

1. A scroll-type fluid machine comprising a rotating main shaft arranged to rotate freely within a housing, a fixed scroll fixed to the housing, an orbiting scroll that orbits relative to the fixed scroll, and a conversion mechanism for converting the rotating motion of the rotating main shaft into the orbiting motion of the orbiting scroll, wherein: The conversion mechanism comprises: an eccentric shaft, the eccentric shaft being arranged on an end surface of the rotating main shaft and being eccentric relative to the rotating main shaft; an eccentric bushing having a through hole for the eccentric shaft to be embedded in; and A bearing is press-fitted into a boss portion formed on the orbiting scroll to support the outer peripheral surface of the eccentric bushing. A lubricating oil supply passage is formed through the eccentric bushing, and the lubricating oil supply passage is used to supply lubricating oil to the bearing. The outlet of the lubricating oil supply passage is arranged on the outer peripheral surface of the eccentric bushing and faces the inner peripheral surface of the bearing. When the lubricating oil is supplied to the bearing by utilizing the centrifugal force generated by the rotation of the rotating main shaft, When viewed from the central axis of the rotating main shaft, the lubricating oil supply flow path is further than the central axis of the eccentric bushing, and The lubricating oil supply flow path includes an axial flow path portion extending along the axial direction of the eccentric bushing and a radial flow path portion extending along the radial direction of the eccentric bushing. The axial flow path portion has an inlet of the lubricating oil supply flow path, and the radial flow path portion has an outlet of the lubricating oil supply flow path.

2. The scroll fluid machine according to claim 1, wherein: When the eccentric bush is divided into a first region and a second region by an imaginary plane including the central axis of the rotating main shaft, the central axis of the eccentric bush, the lubricating oil supply flow path, and the through hole are located in the first region.

3. The scroll fluid machine according to claim 2, wherein: The lubricating oil supply flow path is located farther than the central axis of the eccentric bushing when viewed from the imaginary plane.

4. The scroll fluid machine according to claim 1, wherein: The invention also includes a back pressure chamber formed on the back side of the orbiting scroll and generating a back pressure for pressing the orbiting scroll toward the fixed scroll. In order to supply the lubricating oil in the back pressure chamber to the bearing, an inlet of the lubricating oil supply flow path communicates with the back pressure chamber.

5. The scroll fluid machine according to claim 1, wherein: An inlet of the lubricating oil supply flow path is arranged in a recessed portion formed on an end surface of the eccentric bushing.

6. The scroll fluid machine according to claim 1, wherein: As the bearing, a sliding bearing is used.

Images