Spiral type compressor

Abstract

A spiral-type compressor is provided with which the influence of centrifugal force and the like due to the circular motion of a rotating spiral can be effectively limited compared to the prior art. If, in the spiral-type compressor, when viewed in the axial direction of a rotating shaft 30, a straight line passing through a centerline CL0 of the rotating shaft 30 and a centerline CL2 of an eccentric bushing 72 is defined as a first straight line VL, and a straight line passing through the centerline CL0 of the rotating shaft 30 and orthogonal to the first straight line VL is defined as a second straight line HL, and a center of gravity G1 of the bushing compensator 721, which is integrally provided with the eccentric bushing 72, lies with the second straight line HL between it on the side opposite to the centerline CL2 of the eccentric bushing 72 and with the first straight line VL between it on the side opposite to a centerline CL1 of an eccentric pin 71,and a center of gravity G2 of a shaft compensator 31 provided in one piece with the rotating shaft 30 with the second straight line HL in between lies on the side opposite to the center line CL2 of the eccentric bushing 72 and is on the same side as the center line CL1 of the eccentric pin 71 with respect to the first straight line VL.

Description

TECHNICAL AREA

[0001] The present invention relates to a spiral-type compressor. STATE OF THE ART

[0002] A spiral-type compressor has a stationary spiral and a rotating spiral arranged so that their spiral walls mesh with each other. As the rotating spiral moves in a circular motion relative to the stationary spiral, the volume of a compression chamber formed between their respective spiral walls changes, thereby compressing any fluid drawn into the chamber. A counterweight (also called a balance weight or counterweight) is typically provided in a spiral-type compressor to reduce vibrations and other disturbances caused by the circular motion of the rotating spiral.

[0003] For example, in a spiral-type compressor from patent document 1, a drive force transmission mechanism that transmits drive force to the rotating spiral includes a rotating driven rotary shaft, a crank pin provided at one end of the rotary shaft, and an eccentric bushing that is rotatably mounted on the crank pin from the outside and inserted into a cylinder section provided via a shaft bearing on a rear surface of the rotating spiral, with a compensator being formed integrally with the eccentric bushing. LIST OF REFERENCE DOCUMENTS PATENT DOCUMENTS

[0004] Patent Document 1: JP 2019-100246 A BRIEF SUMMARY OF THE INVENTIONAL TASKS OF THE INVENTION

[0005] For several years now, there has been a demand for even further noise reduction (vibration reduction) in spiral compressors. To achieve this further noise reduction, the influence of centrifugal force and similar factors due to the circular motion of the rotating spiral must be effectively limited compared to the current state of the art.

[0006] The present invention is therefore based on the objective of providing a spiral-type compressor with which the influence of centrifugal force and the like due to the circular motion of a rotating spiral can be effectively limited compared to the prior art. SOLUTION OF THE TASKS

[0007] The inventors of the present invention, through intensive investigations and experiments, have discovered a combination of compensators that effectively limits the influence of centrifugal force and the like due to the circular motion of the rotating spiral, compared to the prior art. The present invention was developed based on these findings.

[0008] According to one aspect of the present invention, a spiral-type compressor comprises a stationary spiral with a stationary support and a stationary spiral wall projecting from the stationary support, a rotating spiral with a rotating support, a rotating spiral wall projecting from a surface of the rotating support and engaging with the stationary spiral wall, and a cylindrical section projecting from another surface of the rotating support, a compression chamber formed by the stationary spiral and the rotating spiral, and A drive force transmission mechanism is employed, comprising a rotating driven shaft, an eccentric pin at one end of the shaft, and an eccentric bushing rotatably mounted on the eccentric pin and rotatably inserted into the interior of the cylinder section via a shaft bearing, transmitting the drive force to the rotating spiral. The spiral compressor is designed such that the volume of the compression chamber changes as the rotating spiral, driven by the drive force, performs a circular motion relative to the stationary spiral, thereby compressing a fluid drawn into the compression chamber.The spiral-type compressor features a bushing compensator that is provided integrally with the eccentric bushing and has a first weight section located on a radially outer side of the eccentric bushing, and a shaft compensator that is provided integrally with the rotating shaft and has a second weight section located on a radially outer side of the rotating shaft.If, when viewed in the axial direction of the rotating shaft, a straight line passing through a centerline of the rotating shaft and a centerline of the eccentric bushing is defined as a first straight line, and a straight line passing through the centerline of the rotating shaft and orthogonal to the first straight line is defined as a second straight line, then a center of gravity of the bushing compensator lies with the second straight line between it on the side opposite to the centerline of the eccentric bushing and with the first straight line between it on the side opposite to the centerline of the eccentric pin, and a center of gravity of the shaft compensator lies with the second straight line between it on the side opposite to the centerline of the eccentric bushing and, with respect to the first straight line, on the same side as the centerline of the eccentric pin. EFFECTS OF THE INVENTION

[0009] According to one aspect of the present invention, a spiral-type compressor can be provided which effectively limits the influence of centrifugal force and the like due to the circular motion of a rotating spiral compared to the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] They show: Fig. 1 a sectional view which schematically illustrates the design of a spiral-type compressor according to a first embodiment; Fig. 2 an enlarged view of essential elements from Fig. 1; Fig. 3 a schematic perspective view illustrating, among other things, a rotating shaft, a bushing compensator and a shaft compensator; Fig. 4 a schematic perspective view illustrating, among other things, the rotating shaft, the bushing compensator and the shaft compensator; Fig. 5 a view of, among other things, the rotating shaft, the bushing compensator and the shaft compensator when viewed from the axial direction of the rotating shaft; and Fig. 6 A view of, among other things, the rotating shaft, the bushing compensator and the shaft compensator when viewed from the axial direction of the rotating shaft (from the to Fig. 5 opposite side). DESCRIPTION OF THE EXECUTION FORMS

[0011] With reference to the attached figures, an embodiment of the present invention is described below.

[0012] Fig. Figure 1 is a sectional view that schematically illustrates the design of a spiral-type compressor according to a first embodiment of the present invention. The spiral-type compressor 10 of this embodiment is, for example, installed in a refrigerant circuit of a vehicle air conditioning system and is designed such that it takes gaseous refrigerant (fluid) of low pressure from the refrigerant circuit, compresses it, pressurizes it, and returns it to the refrigerant circuit. The left side in Fig. 1 is the left side of the compressor 10 of the spiral type, the right side in Fig. 1 is the right side of the compressor 10 of the spiral type, the upper side in Fig. 1 is the upper side of the compressor 10 of the spiral type and the lower side in Fig. 1 is the bottom side of the spiral-type compressor 10. The paper front of Fig. 1 is the left side of the compressor 10 of the spiral type and the paper back of Fig. 1 is the right side of compressor 10 of the spiral type.

[0013] The spiral compressor 10 comprises a housing 20, a rotating shaft 30, an electric motor 40 that rotates the rotating shaft 30, a spiral unit 50 driven by the rotating shaft 30 and which compresses gaseous refrigerant (at low pressure), and an inverter 60 that drives the electric motor 40. The rotating shaft 30, the electric motor 40, the spiral unit 50, and the inverter 60 are housed in the housing 20. The spiral unit 50 includes a stationary spiral 51 and a rotating spiral 52, which performs a circular motion relative to the stationary spiral 51.

[0014] The housing 20 comprises a front housing 21, a cover element 22, a middle housing 23 and a rear housing 24. By connecting these by means of fasteners and the like (not shown), the housing 20 of the spiral-type compressor 10 is formed.

[0015] The front housing 21 has a cylindrical circumferential wall section 211 extending in a front-to-back direction (hereinafter referred to as the "first circumferential wall section") and a partition wall section 212 dividing the interior of the first circumferential wall section 211 in a front-to-back direction (hereinafter referred to as the "first partition wall section"). A front end face of the first circumferential wall section 211 forms a front end face of the front housing 21, and a rear end face of the first circumferential wall section 211 forms a rear end face of the front housing 21. The interior of the first circumferential wall section 211 (i.e., the interior of the front housing 21) is divided by the first partition wall section 212 into a front inverter mounting space, in which the inverter 60 is mounted, and a rear motor mounting space, in which the electric motor 40 is mounted. The electric motor 40 and the inverter 60 are therefore housed in the front casing 21.

[0016] A bearing section 213 is provided on the first partition wall section 212, which supports a front end section of the rotating shaft 30. The bearing section 213 is designed such that it projects cylindrically from the rear surface of the first partition wall section 212 into the engine mounting space and is configured such that it rotatably supports the front end section of the rotating shaft 30 via a first shaft bearing 214.

[0017] A cover element 22 is attached to the front end face of the front housing 21, thereby closing the inverter receiving space (forming an inverter receiving chamber). The front end face of the middle housing 23 is attached to the rear end face of the front housing 21. A sealing element can be arranged between the front housing 21 and the cover element 22, and between the front housing 21 and the middle housing 23, if required.

[0018] The central housing 23 has a cylindrical circumferential wall section 231 extending in a front-to-back direction (hereinafter referred to as the "second circumferential wall section") and a partition wall section 232 dividing the interior of the second circumferential wall section 231 in a front-to-back direction (hereinafter referred to as the "second partition wall section"). A front end face of the second circumferential wall section 231 forms a front end face of the central housing 23, and a rear end face of the second circumferential wall section 231 forms a rear end face of the central housing 23. The interior of the second circumferential wall section 231 (i.e., the interior of the central housing 23) is divided by the second partition wall section 232 into a front connecting space, which is connected to the motor receiving space of the front housing 21, and a rear spiral receiving space in which the spiral unit 50 is received.The spiral unit 50 is therefore included in the middle case 23.

[0019] The second partition wall section 232 has a hollow projection section 233 extending towards the front housing 21 (engine mounting space). The hollow projection section 233 is positioned centrally in the radial direction of the second partition wall section 232, such that it is opposite the bearing section 213 provided on the first partition wall section 212 of the front housing 21. A shaft passage 234 is formed at a crown section (front end) of the hollow projection section 233, connecting the interior and exterior of the hollow projection section 233 and through which the rotating shaft 30 is guided. A second shaft bearing 235 is provided inside the hollow projection section 233, rotatably supporting a portion at the rear end of the rotating shaft 30.In the present embodiment, the rotary shaft 30 extends in the front-back direction in the housing 20 and is rotatably supported by the first shaft bearing 214 provided on the side of the front housing 21 and the second shaft bearing 235 provided on the side of the middle housing 23.

[0020] The front end surface of the rear housing 24 is attached to the rear end surface of the middle housing 23. In the present embodiment, a recessed section 236 is formed on the rear end surface of the middle housing 23, i.e., the rear end surface of the second circumferential wall section 231. This recessed section receives an outer edge section of a stationary support 511 (described below) of a stationary spiral 51 forming the spiral unit 50. The outer edge section of the stationary support 511 is received in the recessed section 236 and clamped between the middle housing 23 and the rear housing 24. In this way, the stationary spiral 51 is fixed, and a rear opening of the second circumferential wall section 231 is closed by the stationary support 511 of the stationary spiral 51. A sealing element can be arranged between the middle housing 23 and the rear housing 24 if required.

[0021] The rear housing 24 is formed in the form of a cylinder with a base and has a cylindrical circumferential wall section 241 extending in a front-to-back direction (hereinafter referred to as the "third circumferential wall section") and a base wall section 242, which closes the opening on the rear side of the third circumferential wall section 241. A front end surface of the third circumferential wall section 241, which forms the front end surface of the rear housing 24, is attached to the rear end surface of the second circumferential wall section 231, which is the rear end surface of the middle housing 23, thereby closing the opening at the front end of the third circumferential wall section 241 by the stationary support 511 of the stationary spiral 51.

[0022] The electric motor 40, for example, is designed as a three-phase motor and includes a stator core unit 41 and a rotor 42.

[0023] The stator core unit 41 is fixed to the inner circumferential surface of the first circumferential wall section 211 of the front housing 21. Direct current, converted to alternating current by the inverter 60, is supplied to the stator core unit 41 from a battery (not shown) installed in the vehicle or the like.

[0024] The rotor 42 is arranged with a defined gap on the radially inner side of the stator core unit 41. A permanent magnet is integrated into the rotor 42. The rotor 42 is cylindrical and fixed to the rotating shaft 30 in a position in which the rotating shaft 30 passes through its hollow inner section. Thus, the rotor 42 is integral with the rotating shaft 30 and rotates integrally with it.

[0025] When an electric field is generated at the stator core unit 41 of the electric motor 40 due to the current supply from the inverter 60, a torque acts on the permanent magnet of the rotor 42, causing the rotor 42 to rotate, which in turn rotates (rotatingly drives) the rotating shaft 30.

[0026] As discussed above, the spiral unit 50 includes a stationary spiral 51 and a rotating spiral 52, which performs a circular motion in relation to the stationary spiral 51.

[0027] The stationary spiral 51 has a circular stationary support 511 and a stationary spiral wall 512 projecting from one surface of the stationary support 511. The stationary spiral wall 512 extends in a helical (involute) shape on one surface of the stationary support 511 from the inner end section (winding start section) on the radially inner side to the outer end section on the radially outer side (winding end section). In the stationary spiral 51, when one surface of the stationary support 511 (the surface on which the stationary spiral wall 512 projects) is facing forward, the outer edge section of the stationary support 511 is received in the recess section 236 and clamped and fixed between the middle housing 23 and the rear housing 24.

[0028] The rotating spiral 52 comprises a circular rotating support 521, a rotating spiral wall 522 projecting from one surface of the rotating support 521, and a cylindrical section 523 projecting from the other surface of the rotating support 521. The rotating spiral wall 522 extends in a helical (involute) shape on one surface of the rotating support 521 from the inner end section (winding start section) on the radially inner side to the outer end section on the radially outer side (winding end section). The cylindrical section 523 projects from the other surface of the rotating support 521 approximately from the middle section. The rotating spiral 52 is arranged such that the rotating spiral wall 522 engages with the stationary spiral wall 512 of the stationary spiral 51.The rotating spiral 52 is thus arranged between the second partition section 232 of the central housing 23 and the stationary spiral 51 in a state in which one surface of the rotating support 521 (the surface from which the rotating spiral wall 522 protrudes) faces rearward. The other surface of the rotating support 521 is sometimes also referred to as the rear surface of the rotating support 521.

[0029] The rotating spiral 52 is driven by a driving force transmitted through the rotating shaft 30 and a crank mechanism 70. The driven rotating spiral 52 is designed such that, in a state where its rotation is inhibited by a self-rotation-inhibiting mechanism 80, it performs a circular motion relative to the stationary spiral 51, i.e., in other words, a circular motion around the axis center of the stationary spiral 51. In the present embodiment, the "driving force transmission mechanism" of the present invention is thus formed by the rotating shaft 30 and the crank mechanism 70.

[0030] The spiral unit 50 receives low-pressure gaseous refrigerant and compresses it by the rotating spiral 52 performing a circular motion relative to the stationary spiral 51. An annular pressure plate 90 is arranged between the rotating support 521 of the rotating spiral 52 and the second partition section 232 of the central housing 23, the rear surface of the second partition section 232 being subjected to a thrust force from the rotating spiral 52 via the pressure plate 90.

[0031] Fig. Figure 2 is an enlarged view of essential elements of Fig. 1 and shows the crank mechanism 70 and the self-rotation inhibiting mechanism 80.

[0032] The crank mechanism 70 couples the rotating shaft 30 and the rotating spiral 52 and is designed to convert the rotary motion of the rotating shaft 30 into the circular motion of the rotating spiral 52. As shown in Fig. As shown in Figure 2, the crank mechanism 70 includes an eccentric pin 71 provided at the rear end of the rotating shaft 30 and an eccentric bushing 72 to which the eccentric pin 71 is attached.

[0033] The eccentric pin 71 extends from the rear end face of the rotating shaft 30 in the axial direction of the rotating shaft 30. The eccentric pin 71 is eccentric with respect to the rotating shaft 30. A center line CL1 of the eccentric pin 71 is therefore offset from a center line CL0 of the rotating shaft 30.

[0034] The eccentric bushing 72 is rotatably mounted on the eccentric pin 71 and rotatably inserted into the cylindrical section 523 of the rotating spiral 52 via a shaft bearing 73. Specifically, the eccentric bushing 72 is cylindrical in shape. Furthermore, a pin passage hole 72a is formed in the eccentric bushing 72, through which the eccentric pin 71 is rotatably guided. The pin passage hole 72a is located eccentrically to the center line CL2 of the eccentric bushing 72 and extends axially through the eccentric bushing 72. The eccentric bushing 72 is rotatably mounted on the eccentric pin 71 by passing the eccentric pin 71 through the pin passage hole 72a. Consequently, the center line of the pin through hole 72a coincides with the center line CL1 of the eccentric pin 71.

[0035] By mounting the eccentric bushing 72 on its outer circumferential surface 72b on the shaft bearing 73 located in the cylindrical section 523 of the rotating spiral 52, it is rotatably inserted into the cylindrical section 523 of the rotating spiral 52 via the shaft bearing 73. The center of gravity of the rotating spiral 52 lies approximately on the center line CL2 of the eccentric bushing 72.

[0036] The self-rotation inhibiting mechanism 80 is designed as a pin-ring-type self-rotation inhibiting mechanism and includes several self-rotation inhibiting sections 81. The self-rotation inhibiting section 81 of the self-rotation inhibiting mechanism 80 is, as in Fig. 2 shown, formed by a ring 82, which is pressed into an annular hole formed on the other surface (rear surface) of the rotating carrier 521, and a pin 83, which is fixed to the second partition section 232 of the central housing 23, extends through the pressure plate 90 and reaches to the inside of the ring 82. In the present embodiment, six annular holes are formed at equal intervals on the other surface (rear surface) of the rotating carrier 521, such that they surround the cylinder section 523, and the rings 82 are pressed into the individual annular holes (see Fig. 3) Six pins 83 are fixed to the second partition section 232 of the central housing 23, corresponding to the six rings 82. In the present embodiment, the self-rotation inhibiting mechanism 80 thus has six self-rotation inhibiting sections 81 arranged at uniform intervals in the circumferential direction. However, there is no limitation to this. As long as three or more self-rotation inhibiting sections 81 are present, the number of self-rotation inhibiting sections 81 can be determined as desired.

[0037] Returning to Fig. 1 The spiral-type compressor 10 has an intake chamber H1 into which low-pressure gaseous refrigerant flows, a compression chamber H2 which compresses the low-pressure gaseous refrigerant, a discharge chamber H3 through which the gaseous refrigerant compressed in the compression chamber H2 is discharged, a gas-liquid separation chamber H4 in which lubricating oil is separated from the gaseous refrigerant compressed by the compression chamber H2, and a compression chamber H5 which is provided on the side of the other surface of the rotating support 521 of the rotating spiral 52 (rear surface).

[0038] The intake chamber H1 is formed by partitions created by the first circumferential wall section 211 of the front housing 21, the first partition wall section 212 of the front housing 21, the second circumferential wall section 231 of the middle housing 23, and the second partition wall section 232 of the middle housing 23. In the present embodiment, the intake chamber H1 is formed by the motor mounting space of the front housing 21 and the connecting section of the middle housing 23. An intake opening P1 is formed in the first circumferential wall section 211. The intake opening P1 is connected to the refrigerant circuit (its low-pressure side) via a connecting line or the like (not shown). Therefore, low-pressure refrigerant flows from the refrigerant circuit through the intake opening P1 into the intake chamber H1.In the central housing 23, a refrigerant channel L1 is formed to direct the gaseous refrigerant from low pressure in the intake chamber H1 to a space H6 near the outer end section of the spiral unit 50.

[0039] The compression chamber H2 is formed between the stationary spiral 51 and the rotating spiral 52. Specifically, during a circular movement of the rotating spiral 52 relative to the stationary spiral 51, the rotating spiral wall 522 of the spiral unit 50 comes into contact with the stationary spiral wall 512, such that a crescent-shaped, hermetically sealed space is formed on the radially outer side by the stationary support 511, the stationary spiral wall 512, the rotating support 521, and the rotating spiral wall 522. The crescent-shaped, hermetically sealed space gradually moves radially inward while its volume decreases. The crescent-shaped, hermetically sealed space formed between the stationary spiral 51 and the rotating spiral 52 constitutes the compression chamber H2.The spiral unit 50 is designed in such a way that, when forming the crescent-shaped hermetically sealed space (i.e., the compression chamber H2), it takes in the low-pressure gaseous refrigerant from space H6 and thus compresses the low-pressure gaseous refrigerant.

[0040] The discharge chamber H3 is formed by partitioning it through the third circumferential wall section 241 of the rear housing 24, the bottom wall section 242 of the rear housing 24, and the stationary support 511 of the stationary spiral 51. The interior of the third circumferential wall section 241 of the rear housing 24 thus forms the discharge chamber H3. A discharge port L2 is formed radially centrally in the stationary support 511 of the stationary spiral 51, connecting the compression chamber H2, which has moved maximally inwards, and the discharge chamber H3. Therefore, in the discharge chamber H3, the gaseous refrigerant compressed by the compression chamber H2 of the spiral unit 50 is discharged through the discharge port L2.A non-return valve (reed valve) 95 is fitted at the discharge port L2, which allows the gaseous refrigerant to flow from the compression chamber H2 into the discharge chamber H3, but prevents the gaseous refrigerant from flowing from the discharge chamber H3 into the compression chamber H2.

[0041] The gas-liquid separation chamber H4 is provided in the rear housing 24. In the present embodiment, the gas-liquid separation chamber H4 is specifically formed as a column-shaped space extending downwards from the outer circumferential surface towards the interior through the bottom wall section 242 of the rear housing 24. The discharge chamber H3 and the gas-liquid separation chamber H4 are connected to each other via a connecting hole L3. An oil separator 100 is arranged in the gas-liquid separation chamber H4, which separates the lubricating oil contained in the gaseous refrigerant. A centrifugal oil separator is used here, but there is no restriction to this type, and another type of oil separator can also be used. A discharge opening P2 is provided above the oil separator 100 in the gas-liquid separation chamber H4.The discharge port P2 is connected to the refrigerant circuit (its high-pressure side) via a connecting line or similar not shown.

[0042] The compression chamber H5 is formed between the rotating support 521 of the rotating spiral 52 and the second partition section 232 of the central housing 23. In the present embodiment, the compression chamber H5 includes the interior of the hollow projecting section 233 of the second partition section 232. A lubricating oil channel L4 is formed in the central housing 23 and rear housing 24, connecting the discharge chamber H3 and the compression chamber H5, and the gas-liquid separation chamber H4 and the compression chamber H5. A constriction (nozzle section) OL is arranged at the lubricating oil channel L4. The compression chamber H5 communicates with the intake chamber H1 via a tiny gap between the inner circumferential surface of the shaft bore 234 and the outer circumferential surface of the rotating shaft 30. However, there is no limitation to this.The compression chamber H5 can also be designed in such a way that it is connected to the intake chamber H1 via a pressure relief channel, on which a constriction or a pressure control valve is provided, or in such a way that it is connected to the compression chamber H2 via a pressure relief channel, on which a throttle valve or a check valve is provided.

[0043] The following is a brief description of the operation of the spiral-type compressor 10.

[0044] When the electric motor 40 rotates the rotating shaft 30 due to the power supply from the inverter 60, the rotation of the rotating shaft 30 is transmitted via the crank mechanism 70 to the rotating spiral 52, causing the rotating spiral 52 to perform a circular motion relative to the stationary spiral 51. Subsequently, the low-pressure gaseous refrigerant from the refrigerant circuit flows through the intake opening P1 into the intake chamber H1, passes through the refrigerant channel L1 into the chamber H6, and is then drawn in and compressed in the compression chamber H2 formed between the stationary spiral 51 and the rotating spiral 52. The gaseous refrigerant (high-pressure gaseous refrigerant) compressed by the compression chamber H2 is discharged through the discharge port L2 (and the check valve 95) into the discharge chamber H3 and then flows through the connecting port L3 into the gas-liquid separation chamber H4.The lubricating oil contained in the gaseous refrigerant flowing into the gas-liquid separation chamber H4 is separated by the oil separator 100. After the lubricating oil has been separated by the oil separator 100, the gaseous refrigerant is fed into the refrigerant circuit through the discharge opening P2. The lubricating oil separated from the gaseous refrigerant by the oil separator 100 collects at the bottom of the gas-liquid separation chamber H4. A portion of the lubricating oil contained in the gaseous refrigerant discharged into the discharge chamber H3 also collects at the bottom of the discharge chamber H3.

[0045] The compression chamber H5 is connected to the discharge chamber H3 and the gas-liquid separation chamber H4 via the lubricating oil channel L4 and to the intake chamber H1 via the tiny gap between the inner circumferential surface of the shaft bore 234 and the outer circumferential surface of the rotating shaft 30. The lubricating oil that has accumulated at the bottom of the discharge chamber H3 and / or the bottom of the gas-liquid separation chamber H4 is therefore fed to the compression chamber H5 via the lubricating oil channel L4, but its pressure is reduced by the constriction OL. The compression chamber H5 and the intake chamber H1 are connected via this tiny gap, and the flow of lubricating oil (and / or gaseous refrigerant) from the compression chamber H5 into the intake chamber H1 is restricted.The pressure in the compression chamber H5 is therefore maintained at an intermediate pressure Pm between the pressure Ps of the intake chamber H1 and the pressure Pd of the discharge chamber H3 (= pressure of the gas-liquid separation chamber H4). This intermediate pressure Pm pushes the rotating spiral 52 towards the stationary spiral 51. Thus, the compression chamber H5 exerts pressure Pm (back pressure) on the rotating spiral 52, which pushes it towards the stationary spiral 51.

[0046] Next, the design for preventing the influence of centrifugal force and the like due to the circular motion of the rotating spiral 52 in the spiral-type compressor 10 is described.

[0047] The fact that the spiral-type compressor 10 has this design is primarily due to the fact that it prevents the occurrence of disruptive noise caused by vibrations of the first shaft bearing 214 and the second shaft bearing 235, which support the rotating shaft 30. It also serves to prevent wear on the stationary spiral wall 512 and / or the rotating spiral wall 522 from increasing with the increasing contact force of the rotating spiral wall 522 against the stationary spiral wall 512, or from damaging the stationary spiral wall 512 and / or the rotating spiral wall 522.

[0048] As a design to prevent the influence of centrifugal force and the like due to the circular motion of the rotating spiral 52, the spiral-type compressor 10 mainly has a compensator 721 provided in one piece with the eccentric bushing 72 (hereinafter referred to as "bushing compensator") and a compensator 31 provided in one piece with the rotating shaft 30 (hereinafter referred to as "shaft compensator").

[0049] Fig. 3 and Fig. Figure 4 shows schematic perspective views illustrating, among other things, the rotary shaft 30, the bushing compensator 721 and the shaft compensator 31. Fig. Figure 5 shows the condition of, among other things, the rotating shaft 30, the bushing compensator 721 and the shaft compensator 31 when viewed from the axial direction of the rotating shaft 30 and Fig. Figure 6 shows the condition of, among other things, the rotating shaft 30, the bushing compensator 721, and the shaft compensator 31 when viewed from the axial direction of the rotating shaft 30 (from the to Fig. 5 opposite side). In the following description, a dimension in the front-back direction, or in other words a dimension corresponding to the axial direction of the rotating shaft 30, denotes the thickness, and a dimension corresponding to the left-right direction denotes the width.

[0050] The bushing compensator 721 is fixed to the outer circumferential surface near the front end of the eccentric bushing 72 (i.e., near the end section on the side of the rotating shaft 30). The bushing compensator 721 rotates integrally with the eccentric bushing 72. The bushing compensator 721 is arranged in the compression chamber H5 (see Fig. 1 and Fig. 2). Reference numeral 74 from Fig. Figure 4 shows a snap ring that secures the eccentric bushing 72 attached to the eccentric pin 71.

[0051] The bushing compensator 721 has a fixing section (hereinafter referred to as the "first fixing section") 722, which is fixed by being placed on an outer circumferential surface 72b of the eccentric bushing 72, a weight section (hereinafter referred to as the "first weight section") 723, which is provided spaced apart from the first fixing section 722 (the eccentric bushing 72) on the radially outer side of the first fixing section 722 (in other words, the eccentric bushing 72), and a coupling section (hereinafter referred to as the "first coupling section") 724, which connects the first fixing section 722 and the first weight section 723.

[0052] The first weight section 723 is block-shaped. In contrast, the first coupling section 724 is plate-shaped. In other words, the first weight section 723 is thicker than the first coupling section 724. When viewing the bushing compensator 721 from the axial direction of the rotating shaft 30, the first weight section 723 and the first coupling section 724 are together semicircular or essentially fan-shaped.

[0053] The first weight section 723 has a rearward projection section 723a (projecting towards the rotating spiral 52) relative to the first coupling section 724, and a first forward projection section 723b and a second forward projection section 723c (projecting towards the rotating shaft 30) relative to the first coupling section 724. In other words, the rear projection section 723a, the first forward projection section 723b, and the second forward projection section 723c each form part of the first weight section 723. The first forward projection section 723b and the second forward projection section 723c are spaced apart from each other in the left-right direction, or in other words, in the direction of rotation R of the rotating shaft 30.In the present embodiment, the first front projection section 723b is formed smaller than the rear projection section 723a, and the second front projection section 723c is formed smaller than the rear projection section 723a and the first front projection section 723b.

[0054] The shaft compensator 31 is fixed to an outer circumferential surface near the rear end of the rotating shaft 30 (i.e., near the end section on the side of the eccentric pin 71). The shaft compensator 31 rotates integrally with the rotating shaft 30. The shaft compensator 31, like the bushing compensator 721, is located in the compression chamber H5. The shaft compensator 31 is situated in the compression chamber H5 in front of the bushing compensator 721 (see Fig. 1 and Fig. 2).

[0055] The shaft compensator 31 has a fixing section (hereinafter referred to as the "second fixing section") 32, which is fixed by being placed on an outer circumferential surface of the rotating shaft 30, a weight section (hereinafter referred to as the "second weight section") 33, which is provided spaced apart from the second fixing section 32 (the rotating shaft 30) on the radially outer side of the second fixing section 32 (in other words, the rotating shaft 30), and a coupling section (hereinafter referred to as the "second coupling section") 34, which connects the second fixing section 32 and the second weight section 33.

[0056] The wave compensator 31 is formed with a generally constant thickness. The second coupling section 34 is narrower than the second fixing section 32 and the second weight section 33.

[0057] In the present embodiment, the distance between the first front projection section 723b and the second front projection section 723c of the bushing compensator 721 in the direction of rotation R of the rotating shaft 30 is set greater than the width of the second coupling section 34 of the shaft compensator 31. The second coupling section 34 of the shaft compensator 31 is arranged between the front projection section 723b and the second front projection section 723c of the bushing compensator 721 (see figure). Fig. 5) Consequently, the bushing compensator 721 rotates integrally with the shaft compensator 31 and can displace a certain amount relative to the shaft compensator 31.

[0058] If in the present embodiment, as in Fig. 5 and Fig.As shown in Figure 6, when viewed from the axial direction of the rotating shaft 30, a straight line passing through the centerline CL0 of the rotating shaft 30 and the centerline CL2 of the eccentric bushing 72 is defined as a first straight line VL, and a straight line passing through the centerline CL0 of the rotating shaft 30 and orthogonal to the first straight line VL is defined as a second straight line HL. Then the first weight section 723 of the bushing compensator 721, with the second straight line HL between it, lies on a side opposite the centerline of the pin through-hole 72a (= centerline CL1 of the eccentric pin 71). A center of gravity G1 of the bushing compensator 721, with the second straight line HL between it, lies on the side opposite the centerline CL2 of the eccentric bushing 72. As discussed above, the center of gravity of the rotating spiral 52 lies approximately on the centerline CL2 of the eccentric bushing 72.Consequently, when viewed from the axial direction of the rotating shaft 30 with the second straight line HL between them, the center of gravity G1 of the bushing compensator 721 lies on the side opposite the center of gravity of the rotating spiral 52. Likewise, the center of gravity G1 of the bushing compensator 721 with the first straight line VL between them lies on the side opposite the center line CL1 of the eccentric pin 71.

[0059] Viewed from the axial direction of the rotating shaft 30, the second weight section 33 of the shaft compensator 31, with the second straight line HL between it, lies on the side opposite the eccentric pin 71. The second coupling section 34 of the shaft compensator 31 is inclined from the second fixing section 32 to the second weight section 33 with respect to the first straight line VL, thus extending at a fixed angle θ (here approximately 20°). A center of gravity G2 of the shaft compensator 31, with the second straight line HL between it, lies on the side opposite the center line CL2 of the eccentric bushing 72. The center of gravity G2 of the shaft compensator 31, like the center of gravity G1 of the bushing compensator 721 with the second straight line HL between them, is therefore located on the side opposite the center of gravity of the rotating spiral 52.The center of gravity G2 of the wave compensator 31 is also on the same side with respect to the first straight line VL as the center line CL1 of the eccentric pin 71.

[0060] According to the compressor 10 of the spiral type of embodiment, the following effects can be achieved.

[0061] The spiral-type compressor 10 has the bushing compensator 721 provided in one piece with the eccentric bushing 72 and the bushing compensator 721 has the first weight section 723 located on the radially outer side of the eccentric bushing 72.

[0062] The centrifugal force resulting from the circular motion of the rotating spiral 52 is therefore canceled out by the centrifugal force occurring at the bushing compensator 721, so that the contact force of the rotating spiral wall 522 against the stationary spiral wall 512 can be maintained appropriately. Consequently, increased wear of the stationary spiral wall 512 and / or the rotating spiral wall 522, or damage to the stationary spiral wall 512 and / or the rotating spiral wall 522, can be prevented. Furthermore, a good seal (hermetic seal) of the compression chamber H2 formed between the stationary spiral 51 and the rotating spiral 52 can be ensured.

[0063] The spiral-type compressor 10 also features the shaft compensator 31, which is integrally formed with the rotating shaft 30. The shaft compensator 31 has the second weight section 33 located on the radially outer side of the rotating shaft 30. Viewed from the axial direction of the rotating shaft 30, the center of gravity G1 of the bushing compensator 721 lies with the second straight line HL between it on the side opposite the center line CL2 of the eccentric bushing 72 and with the first straight line VL between it on the side opposite the center line CL1 of the eccentric pin 71. The center of gravity G2 of the shaft compensator 31 lies with the second straight line HL between it on the side opposite the center line CL2 of the eccentric bushing 72 and, with respect to the first straight line VL, on the same side as the center line CL1 of the eccentric pin 71.

[0064] This design allows for weight balancing in the up-down direction (i.e., along the first straight line VL) and in the left-right direction (i.e., along the second straight line HL, which is orthogonal to the first straight line VL) of the spiral-type compressor 10 according to the embodiment. In particular, the shaft compensator 31 makes it possible to limit the influence of the moment generated by the centrifugal force of the rotating spiral 52 and the bushing compensator 721. Consequently, vibrations / noise from the first shaft bearing 214 and the second shaft bearing 235 supporting the spiral-type compressor 30 are suppressed, thus improving quiet operation (low-vibration operation).

[0065] The bushing compensator 721 has the first front projection section 723b and the second front projection section 723c, which project forward (i.e. towards the shaft compensator 31) and are spaced apart from each other in the direction of rotation of the rotating shaft 30, and the second coupling section 34 of the shaft compensator 31 is arranged between the first front projection section 723b and the second front projection section 723c.

[0066] Therefore, the second coupling section 34 of the shaft compensator 31 serves as a stop that limits the reciprocating movement range of the bushing compensator 721, thus preventing the bushing compensator 721 from moving unnecessarily far back and forth due to inertia and the like. Furthermore, the space required to arrange the shaft compensator 31 and the bushing compensator 721 can be reduced in the axial direction of the rotating shaft 30.

[0067] The combination of the bushing compensator 721 and the shaft compensator 31 described above can also counteract problems resulting from the higher speed and lower weight of the spiral-type compressor 10 (for example, a thinner spiral wall), such as an increase in vibrations / noise during high-speed operation. An example of this is described below.

[0068] If, as a design to limit the influence of centrifugal force and the like due to the circular motion of the rotating spiral 52, the shaft compensator 31 and the bushing compensator 721 are used, a design results in which an imbalance in the course of the circular motion of the rotating spiral 52 (hereinafter referred to as "imbalance (A)"), an imbalance due to the bushing compensator 721 (hereinafter referred to as "imbalance (B)") and an imbalance due to the shaft compensator 31 (hereinafter referred to as "imbalance (C)") cancel each other out.

[0069] Normally, the rotating spiral 52, the bushing compensator 721, and the shaft compensator 31 are in dynamic equilibrium. That is, the following applies: imbalance (A) = imbalance (B) + imbalance (C). However, due to the higher speed and lower weight of the spiral compressor 10, the contact force of the rotating spiral wall 522 against the stationary spiral wall 512 increases during high-speed operation, causing the stationary spiral wall 512 to tilt outwards (elastically).

[0070] When the stationary spiral wall 512 tilts outwards, the radius of rotation AOR of the rotating spiral 52 increases due to the contact between the rotating spiral wall 522 and the stationary spiral wall 512. As the radius of rotation AOR of the rotating spiral 52 increases, the dynamic imbalance of the rotating spiral 52 increases (Imbalance (A) ⇒ Imbalance (A') > Imbalance (A)). As the radius of rotation AOR of the rotating spiral 52 increases, the eccentric bushing 72 (i.e., the bushing compensator 721) moves back and forth on the center point of the eccentric pin 71, thereby decreasing the dynamic imbalance of the bushing compensator 721 (Imbalance (B) ⇒ Imbalance (B')). <Unwucht (B)).

[0071] Even if the rotating spiral 52, the bushing compensator 721 and the shaft compensator 31 are in dynamic equilibrium during operation at low to medium speed, the dynamic equilibrium of the rotating spiral 52, the bushing compensator 721 and the shaft compensator 31 is lost during high-speed operation and "unbalance (A')>unbalance (B')+unbalance (C)" results, so that vibrations / noise increase.

[0072] Vibrations / noise during operation at low to medium speeds are generally low compared to vibrations / noise during high-speed operation. Even if vibrations / noise increase somewhat during operation at low to medium speeds, an overall reduction in vibrations / noise can be achieved for the spiral compressor 10, as long as vibrations / noise decrease during high-speed operation.

[0073] To reduce vibrations / noise during high-speed operation, the imbalance (B) of the shaft compensator 31 is set larger than the imbalance (B) for the case where the radius of circular motion AOR of the rotating spiral 52 is at a design value and compensation between the rotating spiral 52, the bushing compensator 721 and the shaft compensator 31 can be achieved, thus ensuring compensation between the rotating spiral 52, the bushing compensator 721 and the shaft compensator 31 during high-speed operation, i.e.: imbalance (A') = imbalance (B') + imbalance (C).

[0074] As an example, assume that the radius of circular motion AOR of the rotating spiral 52 is about 0.5 to 2% higher than a reference value (design value) during high-speed operation, in which case the imbalance (B) of the bushing compensator 721 can be adjusted so that the dynamic imbalance of the rotating spiral 52 (imbalance (A')) is compensated by the imbalance (C) of the shaft compensator 31 and the dynamic imbalance of the bushing compensator 721 (imbalance (B')) after the reciprocating element of the eccentric bushing 72 due to the increase in the radius of circular motion AOR.

[0075] In this case, vibrations / noise can be reduced during high-speed operation, while during low to medium-speed operation no longer occurs between the rotating spiral 52, the bushing compensator 721, and the shaft compensator 31. This results in "imbalance (A)" <Unwucht (B)+Unwucht (C)“, was bedeutet, dass die Schwingungen / Störgeräusche im Betrieb bei niedriger bis mittlerer Geschwindigkeit zunehmen könnten. Versuchen der Erfinder zufolge wurde jedoch festgestellt, dass durch Anwenden der Kombination des Buchsenausgleichers 721 und des Wellenausgleichers 31 die Schwingungen / Störgeräusche im Betrieb bei niedriger bis mittlerer Geschwindigkeit zwar zunehmen, aber ihr Einfluss gering ist, während sich die Schwingungen / Störgeräusche für den Verdichter 10 des Spiraltyps insgesamt reduzieren lassen.Consequently, the increase in vibrations / noise during high-speed operation can be effectively counteracted due to the higher speed and lower weight of the spiral-type compressor 10.

[0076] In the embodiment described above, the bushing compensator 721 is formed separately from the eccentric bushing 72 and fixed to the outer circumferential surface of the eccentric bushing 72. However, this is not the only possible configuration. The eccentric bushing 72 and the bushing compensator 721 can also be formed as a single component (for example, an eccentric bushing provided with a compensator).

[0077] The foregoing description was made with reference to one embodiment of the present invention and one example of modification, but it is understood that the present invention is not limited to the embodiment and example of modification discussed above and that, of course, further modifications are possible based on the technical concept of the present invention. LIST OF REFERENCE MARKS 10 spiral-type compressors 30 Rotary axis 31 shaft compensators 32 second fixation section 33 second weight section 34 second coupling section 51 stationary spiral 52 rotating spirals 71 eccentric pins 72 Eccentric bushing 73 shaft bearings 511 Fixation carriers 512 stationary spiral wall 521 rotating beam 522 rotating spiral wall 523 cylindrical section 721 Bushing Compensator 722 first fixation section 723 first weight section 723a rear lead section 723b first leading section 723c second front lead section G1 Center of gravity of the bushing compensator G2 Center of gravity of the shaft compensator CL0 Centerline of the axis of rotation CL1 Midline of the eccentric pin CL2 center line of the eccentric bushing H1 Intake chamber H2 compression chamber H3 Discharge chamber H5 Counterpressure chamber HL second straight VL first straight QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2019-100246 A

[0004]

Claims

[1] Scroll type compressor comprising: a stationary spiral with a stationary support and a stationary spiral wall projecting from the stationary support, a rotating scroll having a rotating support, a rotating scroll wall projecting from one surface of the rotating support and engaging with the stationary scroll wall, and a cylinder portion projecting from another surface of the rotating support, a compression chamber formed by the stationary scroll and the rotating scroll, and a drive force transmission mechanism including a rotationally driven rotary shaft, an eccentric pin provided at one end of the rotary shaft, and an eccentric bushing rotatably mounted on the eccentric pin and rotatably inserted into the interior of the cylinder portion via a shaft bearing, and transmitting drive force to the rotating scroll, wherein the volume of the compression chamber changes as the rotating scroll performs a circular movement with respect to the stationary scroll due to the driving force, whereby a fluid taken into the compression chamber is compressed, comprising a bushing balancer provided integrally with the eccentric bushing and having a first weight portion located on a radially outer side of the eccentric bushing, and a shaft balancer provided integrally with the rotary shaft and having a second weight portion located on a radially outer side of the rotary shaft, wherein, when viewed in the axial direction of the rotary shaft, when a straight line passing through a center line of the rotary shaft and a center line of the eccentric bushing is defined as a first straight line and a straight line passing through the center line of the rotary shaft and orthogonal to the first straight line is defined as a second straight line, a center of gravity of the bushing balancer with the second straight line therebetween is on the side opposite to the center line of the eccentric bushing and with the first straight line therebetween is on the side opposite to the center line of the eccentric pin, and a center of gravity of the shaft balancer with the second straight line therebetween is on the side opposite to the center line of the eccentric bushing and is on the same side as the center line of the eccentric pin with respect to the first straight line. [2] The scroll type compressor according to claim 1, wherein the bushing balancer has a first protruding portion and a second protruding portion protruding to the shaft balancer side and spaced apart from each other in the axial direction of the rotary shaft, and a portion of the shaft balancer is disposed between the first protruding portion and the second protruding portion. [3] The scroll type compressor according to claim 2, wherein the bushing balancer further comprises a first fixing portion fixed to an outer peripheral surface of the eccentric bushing, and a first coupling portion connecting the first fixing portion and the first weight portion, wherein the first projection portion and the second projection portion are provided on the first weight portion. [4] The scroll type compressor according to claim 2, wherein the wave balancer further comprises a second fixing portion fixed to an outer peripheral surface of the rotary shaft, and a second coupling portion connecting the second fixing portion and the second weight portion, the second coupling portion being disposed between the first protrusion portion and the second protrusion portion. [5] The scroll type compressor according to claim 4, wherein the second coupling portion extends obliquely with respect to the first straight line when viewed in the axial direction of the rotary shaft.

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