JP6097234B2 - Scroll compressor - Google Patents

Description

  The present invention relates to a scroll compressor that pressurizes fluid in multiple stages.

  Conventionally, in Patent Document 1, as a compressor applied to a so-called gas injection cycle (economizer refrigeration cycle), a low-stage scroll compression mechanism (hereinafter referred to as a low-stage compression mechanism) and a high-stage side are disclosed. There is disclosed a scroll compressor that includes a scroll compression mechanism (hereinafter, referred to as a high-stage compression mechanism) and pressurizes a refrigerant (fluid) in multiple stages by the plurality of compression mechanisms.

  In a compressor having a plurality of compression mechanisms, such as the scroll compressor of Patent Document 1, the physique of the entire compressor is likely to increase in size. In view of this, the scroll compressor disclosed in Patent Document 1 employs a movable scroll provided with spiral tooth portions on both sides in the axial direction of the flat substrate portion, and a low-stage compression mechanism and By arranging the high-stage compression mechanisms close to each other, the size of the entire compressor is reduced.

Japanese Patent No. 3708573

  By the way, as in Patent Document 1, in a scroll type compressor that is applied to a gas injection cycle and boosts the refrigerant in two stages, in order to bring the coefficient of performance (COP) of the gas injection cycle close to the maximum value, The suction volume of the mechanism needs to be set smaller than the suction volume of the low-stage compression mechanism.

  Therefore, in the scroll compressor of Patent Document 1, the amount of axial protrusion of the high stage side movable tooth portion constituting the high stage side compression mechanism of the movable scroll is set to be low, and the low level stage constituting the low stage side compression mechanism of the movable scroll is set. The suction volume of the high-stage side compression mechanism is made smaller than the suction volume of the low-stage side compression mechanism by making it smaller than the axial protrusion amount of the stage-side movable tooth portion. The suction volume is the maximum volume of the compression chamber when the compression mechanism starts to compress the fluid.

  However, when the axial protrusion amount of the high-stage movable tooth portion is smaller than the axial protrusion amount of the low-stage movable tooth portion, when viewed from the radial direction perpendicular to the rotating shaft that transmits the rotational driving force to the movable scroll. In addition, the center of gravity of the movable scroll as a whole tends to shift to the lower stage compression mechanism side than the center part of the substrate part. In general, an eccentric portion is provided on the rotation shaft of the scroll compressor, and the eccentric portion is rotatably fitted in a hole provided on the center side of the substrate portion.

  For this reason, if the center of gravity of the movable scroll deviates from the center of the substrate portion, when the movable scroll is revolved relative to the fixed scroll, the movable scroll is inclined with respect to the rotation axis by the action of centrifugal force. It is easy to end up.

  Furthermore, if the movable scroll rotates in a state inclined with respect to the rotation axis, the airtightness of the compression chamber in each compression mechanism is deteriorated, which causes a decrease in the boosting performance of the compressor. In addition, when the movable scroll comes into contact with the fixed scroll or the like, there is a risk of causing wear or seizure of each compression mechanism.

  In view of the above points, an object of the present invention is to suppress a decrease in pressurization performance of a scroll compressor that pressurizes a fluid in multiple stages.

The present invention has been devised to achieve the above object, and in the invention according to claim 1, a rotating shaft (25) that rotates by obtaining a driving force from a rotating drive source (20), and a rotating shaft The revolving motion is transmitted by the rotational driving force transmitted from (25), and the movable side substrate portion (11a) formed in a flat plate shape and protrudes from the movable side substrate portion (11a) to one axial end side of the rotation shaft (25). A spiral low-stage movable tooth portion (11b) and a spiral high-stage movable tooth portion (11c) projecting from the movable substrate portion (11a) to the other axial end of the rotary shaft (25). A movable scroll (11) having a flat plate, a low-stage side substrate portion (12a), and a low-stage side movable tooth portion (11b) protruding from the low-stage side substrate portion (12a) in the axial direction of the rotary shaft (25). Low stage side fixed tooth portion (12b) having a spiral lower stage fixed tooth portion (12b) meshing with The scroll (12) protrudes in the axial direction of the rotary shaft (25) from the flat plate-like high-stage side substrate portion (13a) and the high-stage side substrate portion (13a), and meshes with the high-stage movable tooth portion (11c). A high-stage fixed scroll (13) having a spiral high-stage fixed tooth (13b),
The space formed between the lower stage side movable tooth part (11b) and the lower stage side fixed tooth part (12b) changes the volume due to the orbiting movement of the movable scroll (11), and the fluid sucked from the outside. A low-stage compression chamber (VL) to be boosted is formed, and a space formed between the high-stage movable tooth portion (11c) and the high-stage fixed tooth portion (13b) is a movable scroll (11). Forms a high-stage side compression chamber (VH) for increasing the pressure of the fluid that has been increased in pressure by the low-stage side compression chamber (VL) by revolving, and the high-stage side movable tooth portion (11c). The axial protrusion amount (HH) of the lower stage side movable tooth portion (11b) is smaller than the axial protrusion amount (HL),
When viewed from the radial direction perpendicular to the rotation axis (25), the lower stage weight (from the center of the movable side substrate part (11a) to the lower stage movable tooth part (11b) side of the movable scroll (11) ( WL) and a scroll compressor in which the high stage side weight (WH) on the high stage side movable tooth part (11c) side is equal from the center part of the movable side substrate part (11a).

  According to this, since the low-stage side weight (WL) and the high-stage side weight (WH) are equal, the entire movable scroll (11) is viewed from the radial direction perpendicular to the rotating shaft (25). The center of gravity is positioned at the substantially central portion of the movable side substrate portion (11a) on the substantially central side. Therefore, when the movable scroll (11) is revolved, the movable scroll (11) can be configured not to easily tilt with respect to the rotation shaft (25).

  As a result, the deterioration of the airtightness of the low-stage compression chamber (VL) and the high-stage compression chamber (VH) due to the movable scroll (11) being inclined with respect to the rotating shaft (25) is suppressed. it can. Furthermore, it is possible to suppress wear and seizure caused by the movable scroll (11) hitting the low stage side fixed scroll (12) and the high stage side fixed scroll (13).

  That is, according to the invention described in this claim, it is possible to suppress a decrease in the boosting performance of the scroll compressor that boosts the fluid in multiple stages.

  In addition, the low stage side weight (WL) and the high stage side weight (WH) in the claims are equal to each other. The low stage side weight (WL) and the high stage side weight (WH) are completely equal. It does not mean only what is being done, but it is meant to include slight differences due to manufacturing errors or the like. That is, the low stage side weight (WL) and the high stage side weight to such an extent that a decrease in the boosting performance of the scroll compressor due to the movable scroll (11) tilting with respect to the rotating shaft (25) can be suppressed. (WH) means matching.

  Specifically, the radial thickness dimension (TL) of the lower stage movable tooth portion (11b) is smaller than the radial thickness dimension (TH) of the higher stage movable tooth portion (11c). The low stage side weight (WL) and the high stage side weight (WH) may be equivalent.

  Furthermore, in the scroll compressor having the above characteristics, the rotating shaft (25) may penetrate the movable side substrate portion (11a). In the configuration in which the rotating shaft (25) penetrates the movable side substrate portion (11a), the movable scroll (11) is easily inclined with respect to the rotating shaft (25). The boosting performance suppressing effect due to the equal side weight (WH) can be effectively obtained.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

It is a whole lineblock diagram of the refrigerating cycle of a 1st embodiment. It is an axial sectional view of the compressor of a 1st embodiment. It is III-III sectional drawing of FIG. It is IV-IV sectional drawing of FIG. It is an axial sectional view of the movable scroll of a 1st embodiment. It is an external appearance perspective view of the movable scroll and Oldham ring of a 2nd embodiment.

(First embodiment)
1st Embodiment of this invention is described using FIGS. A multistage boost type scroll compressor 1 (hereinafter simply referred to as a compressor 1) of the present embodiment is applied to a refrigeration cycle 100 shown in the overall configuration diagram of FIG. This refrigeration cycle 100 fulfills the function of heating the air blown into the air-conditioning target space in the air conditioner.

  Specifically, the refrigeration cycle 100 according to the present embodiment heats the blown air by exchanging heat between the compressor 1 that compresses and discharges the refrigerant, and the high-pressure refrigerant discharged from the compressor 1 and the blown air. 2, a high-stage expansion valve 3 that depressurizes the refrigerant flowing out of the radiator 2 until it becomes an intermediate-pressure refrigerant, and a gas-liquid that separates the gas-liquid of the intermediate-pressure refrigerant decompressed by the high-stage expansion valve 3 A separator 4, a low-stage expansion valve 5 that decompresses the liquid-phase refrigerant separated by the gas-liquid separator 4 until it becomes a low-pressure refrigerant, a low-pressure refrigerant decompressed by the low-stage expansion valve 5, and the outside air It is a vapor compression refrigeration cycle provided with an evaporator 6 that evaporates the low-pressure refrigerant by exchanging heat.

  Further, in the refrigeration cycle 100 of the present embodiment, the gas-phase refrigerant separated by the gas-liquid separator 4 is sucked into the intermediate pressure suction port 32a of the compressor 1, and the low-pressure refrigerant flowing out from the evaporator 6 is taken into the compressor 1. The low pressure suction port 12c is inhaled. That is, in the refrigeration cycle 100 of the present embodiment, the intermediate-pressure refrigerant generated in the cycle (specifically, decompressed by the high-stage expansion valve 3) is compressed by the compressor 1 in the intermediate-pressure refrigerant. It is configured as a gas injection cycle that joins the two.

  The refrigeration cycle 100 employs an HFC-based refrigerant (specifically, R134a) as the refrigerant, and constitutes a subcritical refrigeration cycle in which the high-pressure side refrigerant pressure does not exceed the critical pressure of the refrigerant. Of course, an HFO refrigerant (for example, R1234yf) or the like may be adopted as the refrigerant. Furthermore, the refrigerant is mixed with refrigerating machine oil (oil) for lubricating the sliding portion in the compressor 1, and a part of the refrigerating machine oil circulates in the cycle together with the refrigerant.

  Next, the detailed structure of the compressor 1 of this embodiment is demonstrated using FIGS. In addition, the up and down arrows shown in the axial sectional views of FIGS. 2 to 4 indicate the up and down directions in a state where the compressor 1 is mounted on the refrigeration cycle 100.

  The compressor 1 includes a compression mechanism unit 10 that sucks in refrigerant, compresses and discharges it, an electric motor unit 20 that is a rotational driving source that outputs rotational driving force, and a rotational driving force output from the electric motor unit 20. This is an electric compressor having a shaft 25 or the like that is a rotating shaft for transmitting to and integrated through a housing 30 that forms an outer shell of the compressor 1. As shown in FIG. 2, the compressor 1 is configured as a so-called horizontal type in which the shaft 25 extends in a substantially horizontal direction in a state where the compressor 1 is mounted on the refrigeration cycle 100.

  First, the housing 30 includes a cylindrical member 31 that extends in the horizontal direction, and a motor-side lid member 32 that closes an opening on one end side in the axial direction of the cylindrical member 31 (in FIG. 2, opposite to the compression mechanism unit 10). Have. Furthermore, the opening of the cylindrical member 31 on the other axial end side (in FIG. 2, the compression mechanism unit 10 side) is closed by a low-stage fixed scroll 12 of the compression mechanism unit 10 described later.

  A seal member made of an O-ring or a gasket is disposed at the contact portion between the tubular member 31 and the motor-side cover member 32, the contact portion between the tubular member 31 and the low-stage fixed scroll 12, and the like. The refrigerant does not leak from these contact portions. As a result, an accommodation chamber VA for accommodating the electric motor unit 20 is formed on the inner peripheral side of the cylindrical member 31. Further, the motor-side cover member 32 is formed with an intermediate pressure suction port 32a through which the gas-phase refrigerant separated by the gas-liquid separator 4 flows into the storage chamber VA.

  The electric motor unit 20 includes a stator 21 that forms a stator and a rotor 22 that forms a rotor. The stator 21 includes a stator core 21a made of a magnetic material and a stator coil 21b wound around the stator core 21a. Then, by supplying electric power to the stator coil 21b, a rotating magnetic field for rotating the rotor 22 is generated.

  The rotor 22 has a permanent magnet and is arranged on the inner peripheral side of the stator 21. The rotor 22 is formed in a cylindrical shape extending in the rotation axis direction, and a shaft 25 extending in the rotation axis direction is fixed to the axial center hole of the rotor 22. Therefore, when electric power is supplied to the stator coil 21b and a rotating magnetic field is generated, the rotor 22 and the shaft 25 rotate together.

  In the present embodiment, the shaft 25 and the rotor 22 are fixed by fitting the key 24 into the key grooves formed in the shaft 25 and the rotor 22. 22 may be fixed.

  The shaft 25 is longer in the axial direction than the rotor 22, and the end of the shaft 25 on one end side in the axial direction is formed by a motor unit side bearing portion 25 a disposed at the center of the motor side lid member 32. It is rotatably supported. On the other hand, the other axial end side of the shaft 25 extends so as to penetrate the movable scroll 11 of the compression mechanism unit 10 described later, and is arranged at the center of the high stage fixed scroll 13 of the compression mechanism unit 10 described later. It is rotatably supported by the compression mechanism portion side bearing portion 25b.

  In addition, an oil supply passage 25c for guiding the refrigeration oil to the sliding portion is formed in the shaft 25. The refrigerating machine oil is supplied to the sliding part between the shaft 25 and the motor part side bearing part 25a and the sliding part between the shaft 25 and the compression mechanism part side bearing part 25b through the oil supply passage 25c. In addition, as a motor part side bearing part 25a and a compression mechanism part side bearing part 25b, you may employ | adopt either a rolling bearing or a sliding bearing.

  Next, the compression mechanism unit 10 is formed with a movable scroll 11 that revolves by the rotational driving force transmitted from the shaft 25, and a lower stage fixed tooth part 12b that meshes with the lower stage movable tooth part 11b of the movable scroll 11. The lower stage fixed scroll 12 and the higher stage fixed scroll 13 formed with the higher stage fixed tooth part 13b meshing with the higher stage movable tooth part 11c of the movable scroll 11 are configured.

  More specifically, the movable scroll 11 has a substantially circular flat plate-shaped movable side substrate portion 11a extending perpendicularly to the axial direction of the shaft 25, and the movable side substrate portion 11a includes one end side in the axial direction (FIG. 2). Then, the spiral low-stage movable tooth portion 11b protruding toward the motor portion 20 side) and the other end side in the axial direction (in FIG. 2, on the opposite side of the motor portion 20) from the movable side substrate portion 11a. A projecting spiral high-stage movable tooth portion 11c is formed.

  In addition, a through-hole penetrating the front and back of the movable-side substrate portion 11a is formed in the central portion of the movable scroll 11, and an eccentric portion formed in the shaft 25 and eccentric with respect to the central axis is formed in the through-hole. 25d is slidably inserted.

  The low-stage fixed scroll 12 has a substantially circular flat plate-shaped low-stage substrate portion 12a that is disposed on one end side in the axial direction of the movable scroll 11 and extends perpendicularly to the axial direction of the shaft 25. The part 12a is formed with a spiral lower stage fixed tooth part 12b that protrudes toward the other end side in the axial direction and meshes with the lower stage movable tooth part 11b. In more detail, the low stage side fixed tooth part 12b is formed by the side surface of the spiral groove part in which the low stage side movable tooth part 11b is fitted.

  Further, a through hole is formed in the center of the low stage side fixed scroll 12 so as to penetrate the front and back of the low stage side substrate part 12a. The through hole has a more axial direction than the eccentric part 25d of the shaft 25. A part on one end side is inserted.

  The high stage side fixed scroll 13 is disposed on the other end side in the axial direction from the movable scroll 11, and has a flat plate-like high stage side substrate part 13a extending perpendicularly to the axial direction of the shaft 25. 13a is formed with a spiral high-stage fixed tooth portion 13b that protrudes toward one end in the axial direction and meshes with the high-stage movable tooth portion 11c. More specifically, the high stage side fixed tooth portion 13b is formed by a side surface of a spiral groove portion into which the high stage side movable tooth portion 11c is fitted.

  Further, the above-described compression mechanism side bearing 25b is disposed at the center of the high stage fixed scroll 13, and the end of the shaft 25 on the other end side in the axial direction from the eccentric part 25d is rotatable. It is supported.

  That is, in the compression mechanism unit 10 of the present embodiment, the low-stage fixed scroll 12 is directed from one end side of the shaft 25 toward the other end side (in FIG. 2, from the electric motor unit 20 side to the compression mechanism unit 10 side). The movable scroll 11 and the high-stage fixed scroll 13 are arranged in this order. Further, the shaft 25 is disposed through the front and back of the center portion of the low-stage fixed scroll 12 and the movable scroll 11.

  In the present embodiment, a rotation prevention mechanism 26 that prevents the movable scroll 11 from rotating about the eccentric portion 25 d of the shaft 25 is provided between the movable scroll 11 and the high-stage fixed scroll 13. In FIG. 2, only one rotation prevention mechanism 26 is shown for clarity of illustration, but a plurality of rotation prevention mechanisms 26 may be provided.

  More specifically, in the present embodiment, as the rotation prevention mechanism 26, a pin member 26a extending in the axial direction, and a ring hole 26b in which a cross section viewed from the axial direction is formed in a circular shape to restrict the displacement of the pin member 26a. The pin-hole type formed by is adopted. Further, the pin member 26a is fixed to the surface of the movable side substrate portion 11a of the movable scroll 11 on which the high stage movable tooth portion 11c is arranged by means such as press fitting, and the ring hole 26b is fixed to the high stage side. It is formed on the scroll 13 side.

  By providing this rotation prevention mechanism 26, when the shaft 25 rotates, the movable scroll 11 does not rotate around the eccentric portion 25d, and the rotation center of the shaft 25 is fixed at the low stage side with the center of revolution as the center of revolution. Revolves with respect to the scroll 12 and the high-stage fixed scroll 13.

  Thereby, two scroll compression mechanisms are comprised in the compression mechanism part 10 of this embodiment. That is, the movable scroll 11 and the low-stage fixed scroll 12 constitute a low-stage scroll compression mechanism (low-stage compression mechanism), and the movable scroll 11 and the high-stage fixed scroll 13 constitute a high-stage scroll compression. A mechanism (high-stage compression mechanism) is configured.

  More specifically, in the low-stage side compression mechanism, the low-stage side movable tooth portion 11b of the movable scroll 11 and the low-stage side fixed tooth portion 12b of the low-stage side fixed scroll 12 mesh with each other, and contact at a plurality of locations. As shown in FIG. 3, a crescent-shaped low-stage compression space is formed when viewed from the direction of the rotation axis. This low-stage compression space forms a low-stage compression chamber VL that changes its volume as the movable scroll 11 revolves and compresses the low-pressure refrigerant until it becomes an intermediate-pressure refrigerant.

  Moreover, in this embodiment, as shown in FIG. 3, the winding number of the low stage side movable tooth | gear part 11b is set to one. Here, the “number of windings” indicates a range of a portion that contributes to pressure increase by forming a compression space (compression chamber) in the tooth portion when viewed from the direction of the rotation axis, and makes one round (360 °). The number of turns is 1.

  That is, in FIG. 3, although the low stage side movable tooth part 11b wound so as to occupy a range slightly larger than one round (360 °) is illustrated, in this low stage side movable tooth part 11b, The number of turns in a range where a compression space (compression chamber) is formed and a portion contributing to pressure increase is formed is 1. Further, the “number of windings” may be called “the number of wraps”.

  As shown in FIG. 2, a low-pressure suction port 12 c that sucks low-pressure refrigerant that has flowed out of the evaporator 6 is formed on the outer periphery of the low-stage fixed scroll 12. The low pressure suction port 12c is disposed so as to communicate with the low-stage compression space having the maximum volume.

  Further, when the low-stage fixed scroll 12 is viewed from the axial direction, the lower-stage fixed scroll 12 is located on the outer peripheral side of the shaft 25 and the innermost peripheral portion (winding) of the low-stage movable tooth portion 11b. The intermediate pressure refrigerant compressed in the low-stage compression chamber VL is discharged to a storage chamber VA formed on the inner periphery side of the cylindrical member 31 of the housing 30 at a portion on the inner peripheral side from the start portion). A pressure discharge hole 12d is formed.

  Accordingly, the storage chamber VA functions as a space for accommodating the above-described electric motor unit 20 and also functions as a buffer space for absorbing the pressure pulsation of the intermediate pressure refrigerant discharged from the intermediate pressure discharge hole 12d. Further, a reed valve as a check valve (discharge valve) for preventing the refrigerant from flowing back from the storage chamber VA side to the low-stage compression chamber VL side is disposed at the outlet of the intermediate pressure discharge hole 12d. .

  On the other hand, in the high stage side compression mechanism, the high stage side movable tooth part 11c of the movable scroll 11 and the high stage side fixed tooth part 13b of the high stage side fixed scroll 13 are engaged with each other and contacted at a plurality of locations, so that FIG. As shown, a crescent-shaped high-stage compression space is formed when viewed from the rotational axis direction. The high-stage compression space changes in volume as the movable scroll 11 revolves and forms a high-stage compression chamber VH that compresses the intermediate-pressure refrigerant until it becomes a high-pressure refrigerant.

  Moreover, in this embodiment, as shown in FIG. 4, the number of turns of the high stage side movable tooth part 11c is set to 1 like the low stage side movable tooth part 11b.

  Furthermore, the low-stage movable tooth portion 11b and the high-stage movable tooth portion 11c of the present embodiment are more than when they are arranged in phase with each other when viewed from the axial direction of the shaft 25 (that is, When viewed from the axial direction, the lower-stage compression chamber VL is less than the case where the inner circumferential winding start portion and the outer circumferential winding end portion of each tooth portion 11b, 11c are arranged to overlap each other). The fluctuation range of the total torque fluctuation, which is the sum of the torque fluctuation generated in the shaft 25 due to the pressure fluctuation of the refrigerant in the shaft and the torque fluctuation generated in the shaft 25 due to the pressure fluctuation of the refrigerant in the high-stage compression chamber VH, is arranged to be reduced. ing.

  In other words, the low-stage side movable tooth portion 11b and the high-stage side movable tooth portion 11c are in relation to the central axis when viewed from the axial direction of the rotary shaft so that the fluctuation range of the total torque fluctuation approaches the minimum value. They are shifted in the circumferential direction and arranged in different phases. More specifically, as is clear from the cross-sectional views of FIGS. 3 and 4, the low-stage movable tooth portion 11 b and the high-stage movable tooth portion 11 c are arranged with a 180 ° shift in the circumferential direction with respect to the central axis. Has been.

  Further, in the present embodiment, as shown in FIG. 5, the axial protrusion amount HH (protrusion amount from each substrate portion) of the high stage movable tooth portion 11c and the high stage fixed tooth portion 13b is low stage movable. It is formed smaller than the axial protrusion amount HL (protrusion amount from each substrate portion) of the tooth portion 11b and the lower stage fixed tooth portion 12b. Thereby, the volume ratio between the suction volume of the high-stage compression chamber VH and the suction volume of the low-stage compression chamber VL is adjusted so that the coefficient of performance (COP) of the refrigeration cycle 100 approaches the maximum value.

  Furthermore, in this embodiment, as shown in FIG. 5, the radial thickness dimension TL of the lower stage movable tooth portion 11b is smaller than the radial thickness dimension TH of the higher stage movable tooth portion 11c. As a result, in the movable scroll 11, the lower stage weight WL on the lower stage movable tooth part 11b side from the center part of the movable board part 11a and the higher stage movable tooth part 11c side from the center part of the movable board part 11a. The high stage side weight WH is substantially equal.

  More specifically, the low-stage side weight WL is the weight of the part on the low-stage side movable tooth portion 11b side (left side of the paper) with respect to the center portion shown by the one-dot chain line in FIG. 5, and the high-stage side weight WH is 5 is the weight of the portion on the higher stage side movable tooth portion 11c side (the right side of the drawing) than the center portion indicated by the one-dot chain line in FIG.

  As shown in FIGS. 2 and 3, the intermediate pressure refrigerant formed in the outer peripheral portion of the high-stage fixed scroll 13 so as to penetrate the front and back of the low-stage substrate portion 12 a of the low-stage fixed scroll 12. An intermediate pressure suction port 13c for sucking the intermediate pressure refrigerant in the storage chamber VA is formed through the passage 12f. The intermediate pressure suction port 13c is disposed so as to communicate with the high-stage compression space having the maximum volume.

  Further, when the high-stage fixed scroll 13 is viewed from the axial direction, the innermost peripheral portion (winding) of the high-stage fixed scroll 13 that is on the outer peripheral side of the shaft 25 and is higher than the shaft 25. A high-pressure discharge hole 13d for discharging the high-pressure refrigerant compressed in the high-stage compression chamber VH to the discharge chamber VB is formed in a portion on the inner peripheral side from the start portion). A reed valve as a check valve (discharge valve) for preventing the refrigerant from flowing back to the high-stage compression chamber VH is disposed at the outlet of the high-pressure discharge hole 13d.

  The discharge chamber VB is on the other end side in the axial direction of the high stage side fixed scroll 13 (on the opposite side of the movable scroll 11 in FIG. 2) and on the compression mechanism side disposed on the other end side in the axial direction of the high stage side fixed scroll 13. It is formed in a gap with the lid member 33. The compression mechanism side lid member 33 is one of the constituent members constituting the housing 30. Further, the compression mechanism side lid member 33 is provided with an oil separator 40 for separating the refrigerating machine oil from the compressed high-pressure refrigerant.

  The oil separator 40 is configured by disposing a pipe member 40a having a smaller diameter than the columnar space inside a columnar space VC formed in the compression mechanism side lid member 33 and extending in the vertical direction (vertical direction). Yes. In the oil separator 40, the high-pressure refrigerant containing the refrigerating machine oil flowing into the cylindrical space VC from the discharge chamber VB is swirled around the pipe member 40a, and the refrigerant and the refrigerating machine oil are separated by the action of centrifugal force. ing.

  The refrigerating machine oil separated by the oil separator 40 is guided to the sliding portion of the compression mechanism 20 and the electric motor 30 through the oil passage 40b formed in the compression mechanism side lid member 33, the fixed scroll 22 and the like. On the other hand, the high-pressure refrigerant separated by the oil separator 40 is guided to a high-pressure discharge port 33 a that is formed in the compression mechanism side lid member 33 and discharges the high-pressure refrigerant to the refrigerant inlet side of the radiator 2 of the housing 30.

  Next, the operation of the compressor 1 and the refrigeration cycle 100 of the present embodiment in the above configuration will be described. When electric power is supplied to the motor unit 20 of the compressor 1 and the rotor 22 and the shaft 25 rotate, the movable scroll 11 revolves (turns) with respect to the low-stage fixed scroll 12 and the high-stage fixed scroll 13.

  Accordingly, the low-stage compression chamber VL of the low-stage compression mechanism and the high-stage compression chamber VH of the high-stage compression mechanism rotate and move while reducing the volume from the outer peripheral side to the center side. First, in the low-stage compression mechanism, the low-pressure refrigerant sucked into the low-stage compression chamber VL from the refrigerant outlet side of the evaporator 6 through the low-pressure suction port 12c formed in the low-stage fixed scroll 12 is intermediate pressure. The refrigerant is compressed until it becomes a refrigerant, and is discharged from the intermediate pressure discharge hole 12d into the storage chamber VA.

  The intermediate pressure refrigerant discharged from the intermediate pressure discharge hole 12d flows into the storage chamber VA through the intermediate pressure suction port 32a formed in the motor side lid member 32 (flowed out of the gas-liquid separator 4). Combined with gas-phase refrigerant. At this time, the intermediate pressure refrigerant flows through the gap between the stator 21 and the rotor 22 (that is, inside the electric motor unit 20), whereby the electric motor unit 20 is cooled.

  The combined refrigerant of the intermediate pressure refrigerant discharged from the intermediate pressure discharge hole 12d and the intermediate pressure refrigerant sucked from the intermediate pressure suction port 32a is formed in the high-stage fixed scroll 13 via the intermediate pressure refrigerant passage 12f. The intermediate pressure suction port 13c is sucked into the higher stage compression chamber VH. The intermediate-pressure refrigerant sucked into the high-stage compression chamber VH is compressed until it becomes a high-pressure refrigerant, and is discharged from the high-pressure discharge hole 13d into the discharge chamber VB.

  The high-pressure refrigerant discharged from the high-pressure discharge hole 13d into the discharge chamber VB flows into the oil separator 40 and the refrigerating machine oil is separated. The refrigerating machine oil separated from the high-pressure refrigerant is stored on the lower side of the cylindrical space VC and supplied to each sliding portion via the oil passage 40b and the oil supply passage 25c of the shaft 25. On the other hand, the high-pressure refrigerant from which the refrigerating machine oil is separated is discharged from the high-pressure discharge port 33 a formed in the compression mechanism side lid member 33 to the refrigerant inlet side of the radiator 2.

  In the refrigeration cycle 100, the high-pressure refrigerant discharged from the high-pressure discharge port 33a of the compressor 1 flows into the radiator 2, exchanges heat with the blown air blown into the air-conditioning target space, and dissipates heat. Thereby, blowing air is heated. The refrigerant flowing out of the radiator 2 is decompressed by the high stage side expansion valve 3 until it becomes an intermediate pressure refrigerant, and flows into the gas-liquid separator 4.

  The liquid-phase refrigerant separated by the gas-liquid separator 4 is depressurized by the low-stage expansion valve 5 until it becomes a low-pressure refrigerant, and flows into the evaporator 6. The refrigerant flowing into the evaporator 6 absorbs heat from the outside air and evaporates. The refrigerant flowing out of the evaporator 6 is sucked from the low-pressure refrigerant suction port 11d of the compressor 1 and compressed again. On the other hand, the gas-phase refrigerant separated by the gas-liquid separator 4 is sucked from the intermediate pressure suction port 32a of the compressor 1 and compressed again.

  The refrigeration cycle 100 of the present embodiment operates as described above, and can heat indoor air in the air conditioner. Furthermore, according to the compressor 1 of the present embodiment, the low stage side compression mechanism and the high stage side compression mechanism are arranged close to each other on the front and back of the movable side substrate portion 11a of the movable scroll 11, so that the physique as a whole compressor Can be miniaturized.

  In addition to this, in the compressor 1 of the present embodiment, the shaft 25 is disposed so as to penetrate the center portion of the low-stage fixed scroll 12 and the center portion of the movable scroll 11, and both ends of the shaft 25 are connected to the motor portion side. It is rotatably supported by the bearing portion 25a and the compression mechanism portion side bearing portion 25b.

  As described above, the configuration in which both ends of the shaft 25 are rotatably supported (both-end support) rotates the shaft 25 more stably than the configuration in which only one end of the shaft 25 is rotatably supported (cantilever support). The maximum number of revolutions that can be increased can be increased. Accordingly, in the compressor 1 of the present embodiment, the maximum volume of the compression chambers VL and VH of each compression mechanism necessary for discharging a fluid having a desired flow rate is reduced to further reduce the size of the physique. Can do.

  Here, in the compressor 1 of the present embodiment, in order to bring the COP of the refrigeration cycle 100 close to the maximum value, the axial protrusion amount HH of the high stage movable tooth portion 11c is set to the axial protrusion of the low stage movable tooth portion 11b. It is smaller than the force HL. In such a configuration, when viewed from the radial direction of the shaft 25, the center of gravity of the movable scroll 11 as a whole moves from the central portion of the movable side substrate portion 11a shown by the one-dot chain line in FIG. 5 to the lower stage side movable tooth portion 11b. It tends to shift.

  Furthermore, in the compressor 1 of this embodiment, since the shaft 25 is disposed so as to penetrate the front and back of the central portion of the movable side substrate portion 11a, the center of gravity of the movable scroll 11 as a whole is the central portion of the movable side substrate portion 11a. When the movable scroll 11 is revolved, the movable scroll 11 tends to be inclined with respect to the shaft 25 due to the action of centrifugal force when the movable scroll 11 is revolved.

  And if the movable scroll 11 rotates in the state which inclined with respect to the shaft 25, the airtightness of the compression chambers VL and VH in each compression mechanism will deteriorate, and it will cause the pressure | voltage rise performance of the compressor 1 to fall. Furthermore, when the movable scroll 11 hits the low-stage fixed scroll 12, the high-stage fixed scroll 13, the shaft 25, etc., there is a risk of causing wear or seizure of each compression mechanism.

  On the other hand, in the compressor 1 according to the present embodiment, the radial thickness dimension TL of the low-stage movable tooth portion 11b is made smaller than the radial thickness dimension TH of the high-stage movable tooth portion 11c. The side weight WL and the high stage side weight WH are substantially equal. As a result, as shown in FIG. 5, when viewed from the radial direction of the shaft 25, the center of gravity of the movable scroll 11 as a whole is positioned at the substantially central portion of the movable side substrate portion 11a.

  Therefore, the movable scroll 11 can be configured not to easily tilt with respect to the shaft 25 when the movable scroll 11 is revolved. As a result, the deterioration of the airtightness of the compression chambers VL and VH in each compression mechanism due to the movable scroll 11 being inclined with respect to the shaft 25 can be suppressed. Furthermore, it is possible to suppress wear and seizure due to the movable scroll 11 hitting the low-stage fixed scroll 12 and the like.

  That is, according to the compressor 1 of the present embodiment, it is possible to suppress a decrease in the boosting performance of the scroll compressor that boosts the fluid in multiple stages.

  Further, in the compressor 1 of the present embodiment, the low-stage side weight WL is obtained by making the radial thickness dimension TL of the low-stage movable tooth portion 11b smaller than the radial thickness dimension TH of the high-stage movable tooth section 11c. Therefore, the center of gravity of the movable scroll 11 as a whole can be brought close to the substantially central portion of the movable substrate portion 11a very easily.

  By the way, as in the compressor 1 of the present embodiment, the radial thickness dimension TH of the higher stage movable tooth portion 11c is larger than the radial thickness dimension TL of the lower stage movable tooth portion 11b. The volume tends to be small.

  On the other hand, in the compressor 1 of the present embodiment, a pin-hole type is adopted as the rotation prevention mechanism 26, and the surface on which the high-stage movable tooth portion 11c is arranged in the movable substrate portion 11a. The pin member 26a is fixed. Therefore, the weight of the pin member 26a can be added to the high stage side weight WH, and the radial thickness dimension TH of the high stage side movable tooth portion 11c can be prevented from becoming unnecessarily large.

  Further, in the configuration in which the shaft 25 is disposed through the front and back of the central portion of the movable side substrate portion 11a as in the compressor 1 of the present embodiment, the intermediate pressure discharge hole 12d and the high pressure discharge hole 13d are connected to the shaft 25. It cannot be arranged in the center, and must be arranged on the outer peripheral side of the shaft 25. Therefore, when a plurality of compression chambers VL and VH are formed in each scroll compression mechanism, the refrigerant configuration on the refrigerant discharge side in each scroll compression mechanism tends to be complicated.

  On the other hand, in the compressor 1 of this embodiment, since the number of turns of both the low stage side movable tooth part 11b and the high stage side movable tooth part 11c is 1, the low stage communicated with the intermediate pressure discharge hole 12d. The side compression chamber VL can be formed in a single space. Similarly, the high-stage compression chamber VH communicating with the high-pressure discharge hole 13d can be formed in a single space. Therefore, the refrigerant configuration on the refrigerant discharge side in each scroll compression mechanism is not complicated.

  Moreover, in the compressor 1 of this embodiment, since the low stage side movable tooth part 11b and the high stage side movable tooth part 11c are arrange | positioned 180 degrees in the circumferential direction with respect to the center axis | shaft, total torque fluctuation | variation is carried out. The fluctuation range can be reduced. As a result, it is possible to suppress noise and vibration when the compressor 1 is operated.

(Second Embodiment)
In the first embodiment, an example in which a pin-hole type is adopted as the rotation prevention mechanism has been described, but in this embodiment, an example in which the Oldham ring type rotation prevention mechanism 27 shown in FIG. 6 is adopted will be described.

  More specifically, the rotation prevention mechanism 27 of the present embodiment is a plate formed in an annular shape (a donut shape excluding a small-diameter circular shape arranged coaxially from a circular shape) when viewed from the axial direction. It has an Oldham plate 27a made of a member. The Oldham plate 27 a is disposed between the movable scroll 11 and the low-stage fixed scroll 12.

  Further, a first key portion 27b that protrudes toward the movable scroll 11 and extends in a predetermined direction (substantially horizontal direction in the present embodiment) is formed on the surface of the Oldham plate 27a on the movable scroll 11 side. On the other hand, the surface on the Oldham plate 27a side of the movable scroll 11 (the surface on which the low-stage movable tooth portion 11b is disposed in the movable substrate portion 11a) extends in the same direction as the first key portion 27b, and the first A key groove portion 11e into which the key portion 27b is slidably fitted is formed.

  Further, the surface on the lower stage fixed scroll 12 side of the Oldham plate 27a is rotated by 90 ° with respect to the first key portion 27b when viewed in the axial direction (substantially vertical direction in the present embodiment). A second key portion 27c extending in the direction is formed. On the other hand, on the surface of the Oldham plate 27a of the low-stage fixed scroll 12, a key groove (not shown) is formed that extends in the same direction as the second key portion 27c and into which the second key portion 27c is slidably fitted. .

  The first key portion 27b of the Oldham plate 27a is slidably fitted in the key groove portion 11e of the movable scroll 11, and the second key portion 27c of the Oldham plate 27a is slidable in the key groove of the low-stage fixed scroll 12. The rotation prevention mechanism 27 is configured by being fitted into the. Other configurations and operations are the same as those in the first embodiment.

  Therefore, also in the compressor 1 of this embodiment, the size reduction effect etc. as the compressor 1 whole can be acquired similarly to 1st Embodiment.

  Further, in the compressor 1 of this embodiment, the Oldham ring type is adopted as the rotation prevention mechanism 26, and the key groove portion 11e is formed on the surface of the movable scroll 11 on the Oldham plate 27a side. Therefore, the weight corresponding to the volume of the key groove portion 11e can be subtracted from the low-stage side weight WL, and the radial thickness dimension TH of the high-stage side movable tooth portion 11c is unnecessary as in the first embodiment. Can be suppressed.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be variously modified as follows without departing from the spirit of the present invention.

  (1) In the above-described embodiment, the example in which the multistage boost type scroll compressor 1 according to the present invention is applied to the refrigeration cycle 100 for an air conditioner has been described. However, the application of the scroll compressor 1 according to the present invention is not limited to this. It is not limited to this. That is, the scroll compressor 1 according to the present invention can be applied to a wide range of uses as a compressor that compresses various fluids.

Furthermore, the scroll compressor 1 according to the present invention is
A compressor that compresses and discharges the refrigerant; a radiator that exchanges heat between the high-pressure refrigerant discharged from the compressor and the blown air (or outside air); and a branching portion that branches the flow of the high-pressure refrigerant flowing out of the radiator The high-pressure side expansion valve that depressurizes one high-pressure refrigerant branched at the branching portion until it becomes an intermediate pressure refrigerant, and the other high-pressure refrigerant branched at the branching portion and the high-stage side expansion valve. An internal heat exchanger that exchanges heat with the intermediate pressure refrigerant, a low-stage expansion valve that decompresses the high-pressure refrigerant that has flowed out of the internal heat exchanger until it becomes low-pressure refrigerant, and the low-pressure refrigerant that flows out of the low-stage expansion valve and the outside air An evaporator that heat-exchanges (or blown air) to evaporate the low-pressure refrigerant,
Gas injection configured by causing the intermediate pressure refrigerant flowing out from the internal heat exchanger to be sucked into the intermediate pressure suction port 32a of the compressor 1 and sucking the low pressure refrigerant flowing out from the evaporator into the low pressure suction port 12c of the compressor 1. It may be applied to a cycle.

  Further, in the refrigeration cycle 100 of the above-described embodiment, the example in which the subcritical refrigeration cycle in which the pressure of the refrigerant discharged from the compressor 1 does not exceed the critical pressure of the refrigerant has been described. For example, carbon dioxide or the like is used as the refrigerant. Thus, a supercritical refrigeration cycle in which the pressure of the refrigerant discharged from the compressor 1 exceeds the critical pressure of the refrigerant may be configured.

  (2) In the above-described embodiment, the example in which the refrigeration cycle 100 is applied to an air conditioner and used to heat the blown air has been described. Of course, the refrigeration cycle 100 may be used to cool the blown air. In this case, the radiator 2 may be an outdoor heat exchanger that exchanges heat between the refrigerant and the outside air, and the evaporator 6 may be a use-side heat exchanger that cools the blown air.

  Furthermore, a refrigerant circuit switching means for switching the refrigerant circuit may be provided so that the heat exchanger used as the use side heat exchanger or the outdoor heat exchanger among the radiator 2 and the evaporator 6 may be switched.

  In addition, since the gas injection cycle can improve the COP as compared with the normal refrigeration cycle, the waste heat of the engine (internal combustion engine) is transferred to the passenger compartment in the refrigeration cycle to which the scroll compressor 1 according to the present invention is applied. The present invention is effective when applied to an air conditioner of an electric vehicle that cannot be used for heating the vehicle or a hybrid vehicle that is difficult to use the waste heat of the engine for heating the vehicle interior.

  (3) In the anti-rotation mechanism 27 described in the second embodiment, the key groove portion 11e is formed on the surface of the movable substrate portion 11a where the low step movable tooth portion 11b is disposed, thereby reducing the low step side. Although an example has been described in which the weight WL is reduced and the low-stage side weight WL and the high-stage side weight WH are easily equalized, the following may be adopted as the Oldham ring-type rotation prevention mechanism 27.

  For example, an Oldham ring 27a similar to that of the second embodiment is disposed between the movable scroll 11 and the high-stage fixed scroll 13, and the surface of the movable-side substrate portion 11a on which the high-stage movable tooth portion 11c is disposed. A key portion may be formed, and a key groove into which the key portion is slidably fitted may be formed on the Oldham ring 27a side.

  According to this, the weight of the key portion can be added to the high stage side weight WH, and the radial thickness dimension TH of the high stage side movable tooth portion 11c becomes unnecessarily large as in the first embodiment. Can be suppressed.

  Furthermore, the means for equalizing the high stage side weight WH and the low stage side weight WL is not limited to the means disclosed in the above embodiment. For example, the number of turns of the high-stage movable tooth portion 11c and the number of turns of the low-stage movable tooth portion 11b are set to different values (specifically, the number of turns of the high-stage movable tooth portion 11c is set to the low-stage movable tooth portion 11c). The higher stage weight WH and the lower stage weight WL may be made equal by increasing the number of turns of the portion 11b.

  (4) In the above-described embodiment, an example in which the number of turns of both the low-stage movable tooth portion 11b and the high-stage movable tooth portion 11c is 1 has been described, but the number of turns of both may be 1 or less. The number of turns of either one may be 1 or less.

  (5) In the above-described embodiment, the example in which the low-stage compression mechanism is arranged on the electric motor unit 20 side in the compression mechanism unit 10 and the high-stage compression mechanism is arranged on the opposite side of the electric motor unit 20 has been described. The arrangement of the low-stage compression mechanism and the high-stage compression mechanism is not limited to this. In the compression mechanism unit 10, a high-stage compression mechanism may be disposed on the motor unit 20 side, and a low-stage compression mechanism may be disposed on the opposite side of the motor unit 20.

DESCRIPTION OF SYMBOLS 11 Movable scroll 11a Movable side board | substrate part 11b Low stage side movable tooth part 11c High stage side movable tooth part 12 Low stage side fixed scroll 12b Low stage side fixed tooth part 13 High stage side fixed scroll part 13b High stage side fixed tooth part VL, VH Low stage compression chamber, High stage compression chamber WL, WH Low stage weight, High stage weight

Claims (7)

A rotating shaft (25) that rotates by obtaining a driving force from a rotational drive source (20);
The revolving motion is transmitted by the rotational driving force transmitted from the rotating shaft (25), and the movable side substrate portion (11a) formed in a flat plate shape, and the axis of the rotating shaft (25) from the movable side substrate portion (11a). A spiral low-stage movable tooth portion (11b) projecting toward one end in the direction, and a spiral high-stage side projecting from the movable side substrate portion (11a) to the other axial end of the rotary shaft (25) A movable scroll (11) having a movable tooth portion (11c);
A flat plate-like lower plate portion (12a), and a spiral shape that protrudes from the lower plate portion (12a) in the axial direction of the rotating shaft (25) and meshes with the lower row movable tooth portion (11b). A low stage fixed scroll (12) having a low stage fixed tooth (12b);
A flat plate-like high-stage substrate portion (13a), and a spiral shape that protrudes from the high-stage substrate portion (13a) in the axial direction of the rotating shaft (25) and meshes with the high-stage movable tooth portion (11c). A high stage side fixed scroll (13) having a high stage side fixed tooth part (13b),
The space formed between the low-stage side movable tooth portion (11b) and the low-stage side fixed tooth portion (12b) is changed in volume by the revolving motion of the movable scroll (11) and sucked from the outside. Forming a low-stage compression chamber (VL) that pressurizes the fluid
The space formed between the high stage side movable tooth part (11c) and the high stage side fixed tooth part (13b) changes in volume by the revolving motion of the movable scroll (11), and the low stage stage. Forming a high-stage compression chamber (VH) that pressurizes the fluid pressurized in the side compression chamber (VL);
The axial protrusion amount (HH) of the high-stage movable tooth portion (11c) is smaller than the axial protrusion amount (HL) of the low-stage movable tooth portion (11b).
When viewed from the radial direction perpendicular to the rotating shaft (25), the lower side of the movable scroll (11) from the center of the movable side substrate (11a) to the lower stage movable tooth (11b) side is lower. A scroll characterized in that a step-side weight (WL) is equal to a high-step side weight (WH) on the high-step side movable tooth portion (11c) side from a central portion of the movable-side substrate portion (11a). Mold compressor.   The radial thickness dimension (TL) of the lower stage movable tooth portion (11b) is smaller than the radial thickness dimension (TH) of the higher stage movable tooth portion (11c). Item 2. The scroll compressor according to Item 1. Furthermore, the rotation prevention mechanism (26) which prevents that the said movable scroll (11) rotates with respect to the said rotating shaft (25) is provided,
The rotation prevention mechanism (26) is constituted by a pin member (26a) fixed to the movable scroll (11) and a ring hole (26b) having a circular cross section for restricting displacement of the pin member (26a). And
The said pin member (26a) is being fixed to the surface by which the said high stage side movable tooth | gear part (11c) is arrange | positioned among the said movable side board | substrate parts (11a). Scroll compressor. And a rotation prevention mechanism (27) for preventing the movable scroll (11) from rotating with respect to the rotating shaft (25),
The rotation prevention mechanism (27) includes a key groove portion (11e) formed in the movable scroll (11) and a key portion (27b) slidably fitted in the key groove portion (11e). It is comprised by the cyclic | annular plate-shaped member (27a),
The said keyway part (11e) is formed in the surface by which the said lower stage side movable tooth | gear part (11b) is arrange | positioned among the said movable side board | substrate parts (11a). Scroll compressor.   The scroll compressor according to any one of claims 1 to 4, wherein the rotating shaft (25) passes through the movable substrate portion (11a).   6. The scroll compressor according to claim 5, wherein the number of turns of at least one of the low stage side movable tooth part (11 b) and the high stage side movable tooth part (11 c) is 1 or less. The number of turns of the lower stage movable tooth part (11b) and the number of turns of the higher stage movable tooth part (11c) are equal values.
The low-stage movable tooth portion (11b) and the high-stage movable tooth portion (11c) are arranged with a 180 ° shift in the circumferential direction with respect to the axis center when viewed from the axial direction of the rotating shaft (25). The scroll compressor according to claim 6, wherein the scroll compressor is provided.

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