JP6235964B2 - Scroll compressor - Google Patents

Description

  The present invention relates to a scroll compressor in which a rotating shaft is disposed through a movable scroll.

  Conventionally, a scroll type that revolves the movable scroll with respect to the fixed scroll in a state in which the spiral movable side teeth provided on the movable scroll and the spiral fixed side teeth provided on the fixed scroll are meshed with each other. Compressors are known. In this type of scroll type compressor, the volume of the compression chamber is reduced while the compression chamber formed between the movable side tooth portion and the fixed side tooth portion is displaced from the outer peripheral side to the inner peripheral side, thereby reducing the compression target fluid. Is compressed.

  Further, in the scroll compressor, as disclosed in Patent Document 1, a so-called shaft-through type in which a rotating shaft that transmits a rotational driving force to the movable scroll is disposed through the center of the movable scroll. There are things.

  In this type of shaft-through scroll compressor, the rotation shaft passes through the center portion of the movable scroll, so that the compression chamber cannot be displaced to the center portion of the movable scroll. For this reason, the shaft-through scroll compressor has a smaller theoretical compression ratio and lower compression performance than a normal scroll compressor in which a rotating shaft of the same size does not penetrate the movable scroll. It is easy to end up.

  On the other hand, in the scroll compressor of Patent Document 1, a seal member that is pressed against the fixed scroll by a spring load or the pressure of a fluid to be compressed is applied to the distal end portion (winding start portion) of the movable side tooth portion on the rotating shaft side. It is arranged. Thereby, the airtightness of the compression chamber formed on the innermost peripheral side of the movable scroll and having the highest pressure of the compression target fluid is improved, and the deterioration of the compression performance is suppressed.

  The compression performance can be defined using, for example, the amount of fluid to be compressed that is increased to a desired pressure and discharged to the outside of the compressor when the rotation shaft is rotated once. .

Japanese Patent No. 3216454

  However, as in the scroll compressor of Patent Document 1, in the configuration in which the seal member pressed against the fixed scroll by the spring load or the pressure of the fluid to be compressed is arranged at the winding start portion of the movable side tooth portion, the configuration of the movable scroll Will be complicated.

  In view of the above points, an object of the present invention is to improve the airtightness of a compression chamber with a simple configuration in a scroll compressor in which a rotary shaft is disposed through a movable scroll.

The present invention has been devised in order to achieve the above object. In the invention according to claim 1, the rotating shaft (25) that rotates by obtaining a driving force from the rotating drive source (10), and the rotating shaft The revolving motion is transmitted by the rotational driving force transmitted from (25), and the plate-like movable side substrate portion (11a) and the spiral shape protruding from the movable side substrate portion (11a) in the axial direction of the rotating shaft (25). A movable scroll (11) having a movable side tooth portion (11c), a flat plate-like fixed side substrate portion (13a), and a movable side tooth protruding from the fixed side substrate portion (13a) in the axial direction of the rotary shaft (25) A fixed scroll (13) having a spiral fixed side tooth portion (13b) meshing with the portion (11c),
The rotating shaft (25) penetrates the movable side substrate part (11a), and the space formed between the movable side tooth part (11c) and the fixed side tooth part (13b) is the movable scroll (11). Has a compression chamber (VH) in which the volume of the fluid to be compressed is increased by revolving, and the fluid to be compressed is pressurized.
The involute curve drawn by the outer peripheral wall surface of the movable side tooth portion (11c) is defined as the outer peripheral side involute curve (Io) and the inner peripheral wall surface of the movable side tooth portion (11c) is drawn by the vertical vertical section of the rotating shaft (25). The involute curve is the inner circumference involute curve (Ii), and the curve connecting the rotation axis side end of the outer circumference involute curve (Io) and the rotation axis side end of the inner circumference involute curve (Ii) is the tip curve. (Ic)
The tip curve (Ic) is a combination of two arcs with different diameters, and the diameter of the outer arc (MCo) connected to the outer involute curve (Io) is the inner involute curve ( Ii) is smaller than the diameter of the inner circumferential arc (Ci) connected to
When the movable scroll (11) is displaced to the position where the compression chamber (VH) having the minimum volume is formed, the curvature of the portion of the tip curve (Ic) that contacts the fixed side tooth portion (13b) is the movable side tooth portion. It is characterized by a scroll compressor formed smaller than the curvature of an arc whose diameter is the maximum value (Ti) of the radial thickness dimension (T) of (11c).

  According to this, when the movable scroll (11) is displaced to the position where the compression chamber (VH) having the minimum volume is formed, the curvature of the portion of the tip curve (Ic) that contacts the fixed side tooth portion (13b) is increased. The curvature is formed to be smaller than the curvature of the arc whose diameter is the maximum value (Ti) of the radial thickness dimension (T) of the movable side tooth portion (11c).

  Accordingly, as will be described in detail in an embodiment described later, the tip curve (Ic) is an arc whose diameter is the maximum value (Ti) of the radial thickness dimension (T) of the movable side tooth portion (11c). As compared with the case, the seal length (L) in the gap between the movable side tooth portion (11c) and the fixed side tooth portion (13b) can be increased, and the airtightness of the compression chamber (VH) can be improved. .

  Further, when the movable scroll (11) is displaced to the position where the compression chamber (VH) having the minimum volume is formed, the pressure in the compression chamber (VH) is theoretically highest. Therefore, the airtightness of the compression chamber (VH) where the internal pressure is theoretically highest can be effectively improved.

In other words, according to the present invention, in the scroll compressor in which the rotating shaft (25) is disposed through the movable scroll (11), the curvature of the tip curve (Ic) is extremely reduced. The airtightness of the compression chamber (VH) can be improved with a simple configuration. As a result, it is possible to suppress a decrease in compression performance in the shaft-through scroll compressor.
In the invention according to claim 2, the rotating shaft (25) that rotates by obtaining a driving force from the rotational driving source (10) and the rotational driving force transmitted from the rotating shaft (25) revolves. A movable movable substrate (11) having a flat movable substrate portion (11a) and a spiral movable movable tooth portion (11c) protruding from the movable substrate portion (11a) in the axial direction of the rotation shaft (25); A flat plate-like fixed side substrate portion (13a), and a spiral fixed side tooth portion (13b) protruding from the fixed side substrate portion (13a) in the axial direction of the rotating shaft (25) and meshing with the movable side tooth portion (11c). A fixed scroll (13) having
The rotating shaft (25) penetrates the movable side substrate part (11a), and the space formed between the movable side tooth part (11c) and the fixed side tooth part (13b) is the movable scroll (11). Has a compression chamber (VH) in which the volume of the fluid to be compressed is increased by revolving, and the fluid to be compressed is pressurized.
The involute curve drawn by the outer peripheral wall surface of the movable side tooth portion (11c) is defined as the outer peripheral side involute curve (Io) and the inner peripheral wall surface of the movable side tooth portion (11c) is drawn by the vertical vertical section of the rotating shaft (25). The involute curve is the inner circumference involute curve (Ii), and the curve connecting the rotation axis side end of the outer circumference involute curve (Io) and the rotation axis side end of the inner circumference involute curve (Ii) is the tip curve. (Ic)
The tip curve (Ic) is formed in a semi-elliptical shape with the radial thickness dimension (Ti) of the movable side tooth portion (11c) as the short axis,
When the movable scroll (11) is displaced to the position where the compression chamber (VH) having the minimum volume is formed, the curvature of the portion of the tip curve (Ic) that contacts the fixed side tooth portion (13b) is the movable side tooth portion. It is characterized by a scroll compressor formed smaller than the curvature of an arc whose diameter is the maximum value (Ti) of the radial thickness dimension (T) of (11c).
According to this, the same effect as that of the first aspect of the invention can be obtained.

  Here, the seal length (L) is a portion functioning as a surface seal portion between the movable side tooth portion (11c) and the fixed side tooth portion (13b) in the axial cross section of the rotating shaft (25). Means the length of

  Further, the “outer circumference side involute curve” and the “inner circumference side involute curve” in this claim are not limited to curves that are completely involute curves, but within a range in which the fluid to be compressed can be compressed, Includes curves that deviate slightly from full involute curves. Therefore, the radial thickness dimension (T) of the movable side tooth portion (11c) is not limited to a constant dimension over the entire circumference.

  In addition, the “position where the compression chamber (VH) having the minimum volume” is defined in the present invention is not limited to the position where the volume of the compression chamber (VH) is the smallest, and suppression of a decrease in compression performance is suppressed. To the extent possible, the position just before the volume of the compression chamber (VH) is the smallest is included.

  In addition, the “curvature of the portion of the tip curve (Ic) that contacts the fixed side tooth portion (13b)” in the present claim refers to the portion of the tip portion curve (Ic) that contacts the fixed side tooth portion (13b). When the degree of bending is approximated by an arc having a radius r, it is defined as 1 / r.

  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 explanatory drawing for demonstrating the shape of the high stage side movable side tooth | gear part of the movable scroll of 1st Embodiment. It is the X section enlarged view of Drawing 5 for explaining the shape of the high stage side movable side tooth part. FIG. 6 is an enlarged view of a portion X in FIG. 5 for explaining a seal length. It is a graph which shows the pressure change in the high stage side compression chamber with respect to the change of the rotation angle in the compressor for a comparison. It is a graph which shows the pressure change in the high stage side compression chamber with respect to the change of the rotation angle in the compressor of 1st Embodiment. It is explanatory drawing for demonstrating the positional relationship of the high stage side movable side tooth | gear part and high stage side fixed side tooth | gear part corresponding to a rotation angle. It is explanatory drawing for demonstrating the shape of the high stage side movable side tooth | gear part of 2nd Embodiment. It is explanatory drawing for demonstrating the shape of the high stage | side movable side tooth | gear part of 3rd Embodiment.

(First embodiment)
Hereinafter, the first embodiment of the present invention will be described with reference to FIGS. The scroll compressor 1 of the present embodiment (hereinafter simply referred to as the compressor 1) is a multistage booster compressor that compresses and boosts the fluid to be compressed in multiple stages (two stages in the present embodiment). 1 is applied to the vapor compression refrigeration cycle 100 shown in FIG. Therefore, the compression target fluid of the present embodiment is a refrigerant of the refrigeration cycle 100.

  The refrigeration cycle 100 fulfills the function of heating the air blown into the air-conditioning target space in the air conditioner. More specifically, the refrigeration cycle 100 of the present embodiment includes a radiator 2, a high stage side expansion valve 3, a gas-liquid separator 4, a low stage side expansion valve 5, and an evaporator 6 in addition to the compressor 1. It is configured with.

  The radiator 2 is a heat exchanger for heat dissipation that heats the blown air by exchanging heat between the high-pressure refrigerant discharged from the compressor 1 and the blown air. The high stage side expansion valve 3 is a high stage side pressure reducing means for reducing the pressure of the refrigerant flowing out of the radiator 2 until it becomes an intermediate pressure refrigerant. The gas-liquid separator 4 is a gas-liquid separation unit that separates the gas-liquid of the intermediate pressure refrigerant decompressed by the high stage side expansion valve 3. The low stage side expansion valve 5 is a low stage side pressure reducing means for reducing the pressure of the liquid phase refrigerant separated by the gas-liquid separator 4 until it becomes a low pressure refrigerant. The evaporator 6 is an endothermic heat exchanger that performs heat exchange between the low-pressure refrigerant decompressed by the low-stage expansion valve 5 and the outside air to evaporate the low-pressure refrigerant and exert an endothermic effect.

  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 view of FIG. 2 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.

  In addition, as shown in FIG. 2, the compressor 1 is mounted in the refrigeration cycle 100, the shaft 25 extends in a substantially horizontal direction, and the compression mechanism unit 10 and the electric motor unit 20 are arranged in the horizontal direction. It is configured as a so-called horizontal type.

  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 (on the opposite side of the compression mechanism unit 10 in FIG. 2). ing. The opening of the other end side in the axial direction of the cylindrical member 31 (in FIG. 2, the compression mechanism unit 10 side) is closed by a low-stage fixed scroll 12 of the compression mechanism unit 10 to be described later.

  Seal members made of O-rings are arranged at the contact portion between the cylindrical member 31 and the motor-side cover member 32 and the contact portion between the cylindrical member 31 and the low-stage fixed scroll 12. The refrigerant does not leak from the contact portion. 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 lid 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. Further, a shaft 25 extending coaxially with the rotor 22 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 of the shaft 25 is rotatably supported by a compression mechanism portion side bearing portion 25 b disposed at the center of the high stage fixed scroll 13 of the compression mechanism portion 10.

  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.

  The compression mechanism unit 10 includes a movable scroll 11 that revolves by the rotational driving force transmitted from the shaft 25, and a low stage fixed side tooth part 12 b that meshes with the low stage side movable side tooth part 11 b of the movable scroll 11. The stage-side fixed scroll 12 and the high-stage side fixed scroll 13 formed with the high-stage side fixed-side tooth part 13b that meshes with the high-stage side movable-side 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 11 a that spreads perpendicularly to the axial direction of the shaft 25. The movable side substrate portion 11a includes a spiral low-stage movable side tooth portion 11b that protrudes toward one end side in the axial direction (the motor portion 20 side in FIG. 2), and the other end in the axial direction from the movable side substrate portion 11a. A spiral high-stage movable side tooth portion 11 c that protrudes toward the side (in FIG. 2, opposite to the electric motor portion 20) is formed.

  Furthermore, 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 fixed-side substrate portion 12 a that is disposed on one end side in the axial direction relative to the movable scroll 11 and extends perpendicularly to the axial direction of the shaft 25. The low-stage fixed-side substrate 12a is formed with a spiral low-stage fixed-side tooth 12b that protrudes toward the other end in the axial direction and meshes with the low-stage movable-side tooth 11b. More specifically, the lower stage fixed side tooth portion 12b is formed by a side surface of a spiral groove portion into which the lower stage movable side tooth portion 11b is fitted.

  Furthermore, a through-hole penetrating the front and back of the low-stage fixed side substrate 12a is formed at the center of the low-stage fixed scroll 12, and the through-hole is located more than the eccentric portion 25d of the shaft 25. A site on one end side in the axial direction is inserted.

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

  Furthermore, the compression mechanism part side bearing part 25b mentioned above is arrange | positioned in the center part of the high stage side fixed scroll 13, and the edge part of the axial direction other end side is rotatable rather than the eccentric part 25d among the shafts 25. FIG. 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 so as to penetrate through the center portions of the low-stage fixed scroll 12 and the movable scroll 11.

  In the present embodiment, a rotation prevention mechanism (not shown) that prevents the movable scroll 11 from rotating about the eccentric portion 25d is provided between the movable scroll 11 and the low-stage fixed scroll 12. For this reason, when the shaft 25 rotates, the movable scroll 11 revolves while turning around the center of rotation of the shaft 25 without rotating around the eccentric portion 25d.

  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 (hereinafter referred to as a low-stage compression mechanism). The movable scroll 11 and the high-stage fixed scroll 13 A high-stage scroll compression mechanism (hereinafter referred to as a high-stage compression mechanism) is configured.

  In the low-stage side compression mechanism, the low-stage side movable side tooth part 11b of the movable scroll 11 and the low-stage side fixed side tooth part 12b of the low-stage side fixed scroll 12 are engaged with each other and brought into contact with each other at a plurality of locations. As shown, 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.

  Further, in the present embodiment, as shown in FIG. 3, the number of turns of the low stage side movable side tooth portion 11 b is set to 1. 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 lower stage movable side tooth portion 11b wound so as to occupy a range slightly larger than one round (360 °) is illustrated, in the lower stage movable side tooth portion 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. The “number of windings” is sometimes referred to as the “number of wraps”.

  Further, 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 peripheral portion 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.

  Furthermore, 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 is the innermost peripheral portion of the low-stage movable side tooth portion 11b ( As shown in FIGS. 2 and 3, the intermediate pressure refrigerant compressed in the low-stage compression chamber VL is placed on the inner peripheral side of the cylindrical member 31 of the housing 30 at the site on the inner peripheral side of the winding start portion). An intermediate pressure discharge hole 12d is formed for discharging into the storage chamber VA formed in.

  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. At the outlet of the intermediate pressure discharge hole 12d, a reed valve (not shown) 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.

  On the other hand, in the high stage side compression mechanism, the high stage side movable side tooth part 11c of the movable scroll 11 and the high stage side fixed side tooth part 13b of the high stage side fixed scroll 13 are engaged and contacted at a plurality of locations. As shown in FIG. 4, a crescent-shaped high-stage compression space is formed when viewed from the direction of the rotation axis. 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.

  Furthermore, in this embodiment, as shown in FIG. 4, the number of turns of the high-stage movable side tooth portion 11c is set to 1 similarly to the low-stage movable side tooth portion 11b. Accordingly, the cross-sectional shapes (see FIG. 4) of the high-stage movable side tooth portion 11c and the high-stage fixed side tooth portion 13b in the axial vertical cross section (hereinafter referred to as the axial vertical cross section) of the shaft 25 are The cross-sectional shape (see FIG. 3) of the low-stage movable side tooth portion 11b and the low-stage fixed side tooth portion 12b in the vertical cross section is substantially the same.

  The detailed configurations of the low stage movable side tooth portion 11b and the low stage side fixed side tooth portion 12b, and the high stage side movable side tooth portion 11c and the high stage side fixed side tooth portion 13b will be described later.

  Further, as shown in FIGS. 2 and 4, an intermediate pressure suction port 13 c that sucks the intermediate pressure refrigerant in the storage chamber VA is formed on the outer peripheral portion of the high-stage fixed scroll 13. The intermediate pressure suction port 13c is disposed so as to communicate with the high-stage side compression space having the maximum volume, and penetrates the front and back of the low-stage side fixed-side substrate portion 12a of the low-stage side fixed scroll 12. The intermediate pressure refrigerant is sucked through the formed intermediate pressure refrigerant passage 12f.

  Further, when the high-stage fixed scroll 13 is viewed from the axial direction, the innermost peripheral portion of the high-stage movable side tooth portion 11c (on the outer peripheral side of the shaft 25 of the high-stage fixed scroll 13 ( As shown in FIGS. 2 and 4, 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 winding start portion). Has been.

  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 components constituting the housing 30, and the compression mechanism side lid member 33 has a high pressure discharge port 33 a for discharging high pressure refrigerant from the compressor 1 to the radiator 2 side. Is formed.

  Accordingly, the discharge chamber VB functions as a buffer space that absorbs the pressure pulsation of the high-pressure refrigerant discharged from the high-pressure discharge hole 13d. Further, the discharge chamber VB also functions as a refrigerating machine oil separating unit that separates the refrigerating machine oil from the high-pressure refrigerant discharged from the high-pressure discharge hole 13d and stores the separated refrigerating machine oil on the lower side.

  At the outlet of the high-pressure discharge hole 13d, a reed valve is disposed as a check valve (discharge valve) (not shown) that prevents the refrigerant from flowing backward from the discharge chamber VB to the high-stage compression chamber VH. Therefore, the gas-phase refrigerant separated in the discharge chamber VB is discharged from the high-pressure discharge port 33a to the radiator 2 side, and the refrigerating machine oil stored on the lower side of the discharge chamber VB is formed inside the shaft 25. It is supplied to each sliding part of the compressor 1 through the oil supply passage 25c and the like.

  Next, detailed configurations of the low stage movable side tooth portion 11b and the low stage side fixed side tooth portion 12b, and the high stage side movable side tooth portion 11c and the high stage side fixed side tooth portion 13b will be described.

  First, the arrangement of the low stage side movable side tooth part 11b and the low stage side fixed side tooth part 12b, and the high stage side movable side tooth part 11c and the high stage side fixed side tooth part 13b will be described.

  The low-stage side movable side tooth portion 11b and the high-stage side movable side tooth portion 11c of the present embodiment are more than when they are arranged so as to be in phase with each other when viewed from the axial direction of the shaft 25 (that is, When viewed from the axial direction, the width of the total torque variation is greater than when 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). Are arranged to shrink.

  The total torque fluctuation is a value obtained by adding the torque fluctuation generated in the shaft 25 due to the refrigerant pressure fluctuation in the low-stage compression chamber VL and the torque fluctuation generated in the shaft 25 due to the refrigerant pressure fluctuation in the high-stage compression chamber VH. It is.

  In other words, the low-stage movable side tooth portion 11b and the high-stage movable side tooth portion 11c have a 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. On the other hand, they are shifted in the circumferential direction and arranged in different phases. Specifically, as shown in the cross-sectional views of FIGS. 3 and 4, the low-stage movable side tooth portion 11b and the high-stage movable side tooth portion 11c are shifted from each other by 180 ° in the circumferential direction with respect to the central axis. Has been placed.

  For this reason, the lower stage fixed side tooth part 12b and the higher stage fixed side tooth part 13b are also centered on each other so as to mesh with the lower stage movable side tooth part 11b and the lower stage fixed side tooth part 12b, respectively. On the other hand, they are displaced by 180 ° in the circumferential direction.

  Next, the cross-sectional shape in the axial vertical cross section of the high stage side movable side tooth part 11c and the high stage side fixed side tooth part 13b is demonstrated using FIG. 5, FIG. 5 and 6, the high-stage movable side tooth portion 11c of the movable scroll 11 is displaced with respect to the high-stage fixed side tooth portion 13b to a position where the high-volume side compression chamber VH having the minimum volume is formed. Shows the state.

  Here, in a general scroll compression mechanism, the shape of the tooth portion in the axial vertical cross section of the rotating shaft is formed in an involute curve shape. Further, since the tooth portion formed in a spiral shape has a thickness in the radial direction, the tooth portion of a general scroll compression mechanism has a tip portion (winding start portion) on the rotary shaft side in the vertical cross section in the axial direction. The cross-sectional shape is formed in an arc shape as indicated by a broken line in FIG.

  On the other hand, in the present embodiment, as shown in FIGS. 5 and 6, the involute curve drawn by the outer peripheral wall surface of the high-stage movable side tooth portion 11c in the axially vertical cross section is defined as the outer peripheral side involute curve Io, The involute curve drawn by the inner peripheral wall surface of the high stage side movable tooth portion 11c is defined as the inner peripheral side involute curve Ii, and the shaft 25 side end portion (the winding start portion side end portion) that is the rotating shaft side end portion of the outer peripheral side involute curve Io. ) And the winding start side end of the inner circumferential involute curve Ii is defined as a tip end curve Ic.

  The outer circumferential side involute curve Io and the inner circumferential side involute curve Ii are not limited to curves that are complete involute curves, and are slightly different from the complete involute curves as long as the high-stage compression mechanism can compress the refrigerant. It may be a shifted curve.

  At this time, in the present embodiment, the tip curve Ic has a shape combining two circular arcs having different diameters (a shape in which two circular arcs having different diameters are smoothly connected), and is connected to the outer circumferential involute curve Io. The diameter of the outer peripheral side arc Co to be formed is smaller than the diameter of the inner peripheral side arc Ci connected to the inner peripheral side involute curve Ii.

  Accordingly, in the tip end curve Ic of the present embodiment, when the movable scroll 11 is displaced to a position where the high volume side compression chamber VH having the minimum volume is formed, the tip stage curve Ic is moved to the high stage side fixed side tooth portion 13b. The curvature of the part in contact is smaller than the curvature of the arc indicated by the broken line in FIG. 6 having the maximum value Ti of the radial thickness dimension T on the axial center side of the high-stage movable side tooth portion 11c.

  Here, the curvature of the portion of the tip curve Ic that is in contact with the high-stage fixed side tooth portion 13b is the curvature of the portion of the tip curve Ic that is in contact with the high-stage fixed side tooth portion 13b. Is defined as 1 / r. Moreover, the circular arc shown with the broken line of FIG. 6 can also be expressed as a tip end curve drawn by a movable side tooth portion adopted in a general scroll compressor.

  Further, the winding start portion of the high-stage fixed side tooth portion 13b (that is, the groove formed in the high-stage side fixed scroll 13) is rotated by the high-stage side movable side tooth portion 11c when the movable scroll 11 revolves. The winding start portion is in contact with the high-stage compression chamber VH and is formed in a shape capable of compressing the refrigerant. Specifically, the cross-sectional shape of the winding start portion of the high-stage fixed side tooth portion 13b in the vertical cross section in the axial direction of the present embodiment is a shape in which two circular arcs having substantially different diameters are combined.

  In FIG. 6, black circles indicate the connection portion between the outer circumference side involute curve Io and the outer circumference side arc Co, the connection portion between the outer circumference side arc Co and the inner circumference side arc Ci, and the inner circumference side arc Ci and the inner circumference side involute. This is illustrated for explaining the connection with the curve Ii, and such a black dot does not exist in the actual cross section.

  Furthermore, as described above, the cross-sectional shapes of the low-stage movable side tooth portion 11b and the low-stage side fixed side tooth portion 12b in the axial vertical cross section are the high-stage side movable side tooth portion 11c and the high-stage side fixed side tooth portion 13b. The cross-sectional shape is substantially the same. Therefore, the cross-sectional shapes of the winding start portions of the low stage side movable side tooth part 11b and the low stage side fixed side tooth part 12b in the axial vertical cross section are also the high stage side movable side tooth part 11c and high stage side fixed side tooth part, respectively. It is equivalent to the cross-sectional shape of the winding start part of 13b.

  Further, in the present embodiment, as shown in FIG. 2, the axial dimensions of the high stage side movable side tooth part 11c and the high stage side fixed side tooth part 13b (the amount of protrusion from each substrate part) are low stage side movable. The side teeth 11b and the lower stage fixed side teeth 12b are formed to be shorter than the axial dimension (amount of protrusion from each substrate). Thus, the volume ratio between the maximum volume of the high-stage compression chamber VH and the maximum 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.

  Next, the operation of the compressor 1 and the refrigeration cycle 100 of the present embodiment configured as described above 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. In the low-stage compression mechanism, the low-pressure refrigerant flowing from the evaporator 6 is sucked into the low-stage compression chamber VL from the low-pressure suction port 12c formed in the low-stage fixed scroll 12. The low-pressure refrigerant sucked into the low-stage compression chamber VL is compressed until it becomes an intermediate-pressure 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 to the discharge chamber VB is discharged from the high-pressure discharge port 33a formed in the compression mechanism side lid member 33 to the refrigerant inlet side of the radiator 2 after the refrigeration oil is separated in the discharge chamber VB. On the other hand, the refrigerating machine oil separated in the discharge chamber VB is supplied to each sliding portion via the oil supply passage 25c of the shaft 25.

  Further, 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 and radiates heat by exchanging heat with the blown air blown into the air-conditioning target space. 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 intermediate-pressure liquid-phase refrigerant separated by the gas-liquid separator 4 is decompressed 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 intermediate pressure 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 compressor 1 of the present embodiment operates as described above, and can compress and discharge the refrigerant in the refrigeration cycle 100. Moreover, in the refrigerating cycle 100, indoor air can be heated in an 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 shaft-through scroll compressor in which the shaft 25 is disposed through the center of the movable scroll 11 like the compressor 1 of the present embodiment, the compression chamber is displaced to the center of the movable scroll. I can't let you. For this reason, a shaft-through scroll compressor has a theoretical compression ratio that is smaller than that of a normal scroll compressor that has the same physique and the rotating shaft does not pass through the movable scroll. It is easy to end up.

  On the other hand, in the compressor 1 of this embodiment, since the thing of the cross-sectional shape mentioned above is employ | adopted as the high stage side movable side tooth part 11c and the low stage side movable side tooth part 11b, it demonstrates below. As described above, it is possible to improve the air tightness of the high pressure side compression chamber when the refrigerant pressure becomes the highest, and to suppress the deterioration of the compression performance.

  In this embodiment, the cross-sectional shape in the axial vertical section of the winding start portion of the high-stage movable side tooth portion 11c and the cross-sectional shape in the axial vertical section of the winding start portion of the low-stage movable side tooth portion 11b are as follows. It is formed equally. Therefore, in the compressor 1 of the present embodiment, the same compression performance reduction suppression effect can be obtained in both compression mechanisms. Therefore, in the following description, the high-stage compression mechanism will be described as an example.

  First, in the high stage side compression mechanism, when the movable scroll 11 is displaced to a position where the minimum volume high stage side compression chamber VH is formed, the high stage side movable side tooth part 11c and the high stage side fixed side tooth part 13b Leakage amount of refrigerant leaking from the high-pressure side high-stage compression chamber VH having a minimum volume to the outer-stage high-stage compression chamber VH formed on the outer peripheral side of the high-stage movable side tooth portion 11c Q will be described.

This leakage amount Q can be defined by a model equation of gap leakage between two planes shown below in Formula F1.
^{Q = (bh 3 / 12μL)} × ΔP ... (F1)
In Formula F1, b is the axial dimension (amount of protrusion from each substrate portion) of the high stage movable side tooth portion 11c and the high stage side fixed tooth portion 13b. h is a clearance dimension between the high stage side movable side tooth part 11c and the high stage side fixed side tooth part 13b. μ is the viscosity of the refrigerant (fluid to be compressed). ΔP is a differential pressure obtained by subtracting the refrigerant pressure P2 in the high pressure side compression chamber VH on the outer peripheral side from the refrigerant pressure P1 in the high pressure side compression chamber VH on the high pressure side.

  Furthermore, L is the seal length of the gap between the high stage movable side tooth portion 11c and the high stage side fixed side tooth portion 13b. The seal length L is a length of a portion that functions as a surface seal portion between the high stage side movable side tooth portion 11c and the high stage side movable side tooth portion 13b in the vertical cross section in the axial direction. Therefore, the leakage amount Q can be reduced by increasing the seal length L.

  Here, as described above, in the scroll compressor, the shape of each tooth portion in the axial vertical section of the rotating shaft is formed in an involute curve. For this reason, in the scroll compressor, the gap dimension h does not become a constant value. Therefore, in the present embodiment, the seal length L is a range where the gap dimension h is not more than a predetermined reference dimension (specifically, 30 μm) in the vertical cross section in the axial direction.

  Furthermore, in this embodiment, when the movable scroll 11 is displaced to a position where the high-stage side compression chamber VH having the minimum volume is formed, the high-stage side fixed portion of the tip curve Ic drawn by the high-stage movable side tooth portion 11c is fixed. The curvature of the portion in contact with the side tooth portion 13b is formed to be smaller than the curvature of the arc indicated by the broken line in FIGS. 6 and 7 where the maximum value Ti of the radial thickness dimension T of the high stage side movable tooth portion 11c is the diameter. ing.

  Therefore, as shown in FIG. 7, the seal length L (the range in which the gap dimension h is 30 μm) of the compressor 1 of the present embodiment is such that the tip curve Ic is an arc indicated by a broken line in FIG. The seal length is longer than the seal length L0. As a result, the amount of leakage Q from the high-pressure side high-stage compression chamber VH to the outer-stage high-stage compression chamber VH can be reduced, and the airtightness of the high-pressure side high-stage compression chamber VH can be improved. .

  Furthermore, when the movable scroll 11 is displaced to a position where the high volume side compression chamber VH having the minimum volume is formed, the pressure in the high volume side compression chamber VH having the minimum volume is theoretically highest. Therefore, it is possible to effectively improve the airtightness of the high-stage compression chamber VH in which the internal pressure is theoretically highest.

  That is, according to the compressor 1 of the present embodiment, in the scroll-type compressor on the shaft penetrating side where the shaft 25 is disposed through the movable scroll 11, an extremely simple configuration that reduces the curvature of the tip end curve Ic. Thus, the air tightness of the high-stage compression chamber VH can be improved. As a result, it is possible to suppress a decrease in compression performance in the shaft-through scroll compressor 1.

  Moreover, in the present embodiment, the tip end curve Ic is formed in a shape combining two arcs having different diameters so that the diameter of the outer circumference side arc Co is smaller than the diameter of the inner circumference side arc Ci. Yes. Accordingly, the curvature of the portion of the tip curve Ic that contacts the high-stage fixed side tooth portion 13b is very easily converted into a circular arc whose diameter is the maximum value Ti of the radial thickness dimension T of the high-stage side movable side tooth portion 11c. It can be made smaller than the curvature.

  Furthermore, the present inventors have confirmed the specific effect of the compressor 1 of this embodiment with respect to a general shaft-through scroll compressor by a test study described below. In a test study conducted by the present inventors, a general shaft-through scroll compressor is formed such that the tip curve Ic of the high-stage movable side tooth portion 11c is an arc indicated by a broken line in FIG. A comparative scroll type compressor (hereinafter referred to as a comparative compressor) is used.

  In this comparative compressor, when the movable scroll 11 revolves, the winding start portion of the high-stage movable side tooth portion 11c comes into contact with the winding start portion of the high-stage side fixed tooth portion 13b. In order that the refrigerant can be compressed in the side compression chamber VH, a cross-sectional shape in the vertical cross section in the axial direction is formed so as to be an arc as shown by a one-dot chain line in FIG.

  Furthermore, when the radius of the tip curve in the comparative compressor is R0, the inner circumference side arc Ci of the tip curve Ic of the compressor 1 of the present embodiment is 1.5 times R0.

That is, R0 and Ci have a dimensional relationship shown in the following formulas F2 and F3.
R0 = 0.5 × Ti (F2)
Ci = 1.5 × R0 = 0.75 × Ti (F3)
Here, Ti is the maximum value of the radial thickness dimension T of the high-stage movable side tooth portion 11c. With such a dimensional relationship, in the compressor 1 of the present embodiment, the seal length L can be increased by about 15% with respect to the seal length L0 of the comparative compressor.

  Next, changes in refrigerant pressure in the compressor 1 and the comparative compressor of the present embodiment will be described with reference to FIGS. 8 and 9.

  In the graphs of FIGS. 8 and 9, the ideal pressure of the high-pressure side high-pressure side compression chamber VH with respect to the rotation angle θ of the high-level side movable tooth portion 11c is indicated by a thick broken line, and the high-pressure side high-pressure side The measured value of the pressure in the compression chamber VH (specifically, the pressure at the position indicated by P1 in FIG. 7) is indicated by a bold solid line, and the pressure (specifically, the pressure in the high-stage compression chamber VH on the outer peripheral side is shown in FIG. The actual measurement value of the pressure at the position indicated by P2 in FIG.

  FIG. 10 shows the positional relationship between the high stage movable side tooth portion 11c and the high stage fixed side tooth portion 13b corresponding to the rotation angle θ of the horizontal axis of the graphs of FIGS. Furthermore, the pressure at the location indicated by P1 in FIG. 7 is equal to the pressure in the region indicated by point hatching in FIG.

  First, in the comparative compressor, as shown in FIG. 8, as the rotation angle θ increases from 0 °, the pressure of the refrigerant sucked from the intermediate pressure suction port 13c into the high-stage compression chamber VH increases. . When the rotation angle θ reaches about 160 °, the refrigerant pressure in the high-pressure side high-pressure side compression chamber VH reaches the discharge pressure and begins to be discharged from the high-pressure discharge hole 13d.

  However, when the rotation angle θ reaches about 330 °, the refrigerant pressure P1 decreases and the high-pressure refrigerant is not discharged.

  Such a decrease in the refrigerant pressure P1 is caused by the fact that the refrigerant in the high-pressure side high-stage compression chamber VH has a high-stage side on the outer peripheral side from the gap between the high-stage movable-side tooth portion 11c and the high-stage-side fixed tooth portion 13b. This is caused by leakage into the compression chamber VH. This is clear from the fact that when the rotation angle θ reaches about 330 °, the refrigerant pressure P2 in the outer high-side compression chamber VH starts to rise.

  That is, in the comparative compressor, when the rotation angle θ is in the range of approximately 160 ° to 330 °, the refrigerant whose pressure has been increased to a desired pressure (discharge pressure) can be discharged, but the rotation angle θ is 330 °. In the range of ˜360 °, the refrigerant in the high-pressure side high-compression chamber VH leaks to the high-pressure side compression chamber VH on the outer peripheral side, and the refrigerant in the high-pressure side high-pressure side compression chamber VH is discharged. I can't.

  On the other hand, in the compressor 1 of the present embodiment, since the airtightness of the high-stage compression chamber VH can be improved as described above, the leakage amount Q can be reduced by about 7% with respect to the comparative compressor. . As a result, as shown in FIG. 9, it is possible to discharge the refrigerant whose pressure has been increased to a desired pressure when the rotation angle θ is approximately in the range of 160 ° to 350 °.

(Second Embodiment)
This embodiment demonstrates the example which changed the shape of the front-end | tip part curve Ic of the low stage side movable side tooth part 11b and the high stage side movable side tooth part 11c with respect to 1st Embodiment. In the present embodiment, the same effect can be obtained by both the low-stage compression mechanism and the high-stage compression mechanism, and therefore, in the following description, the high-stage compression mechanism will be described as an example.

  Specifically, as shown in FIG. 11, the tip end curve Ic of the present embodiment is formed in a semi-elliptical shape with the radial direction thickness dimension Ti of the high-stage movable side tooth portion 11c as the short axis. Furthermore, also about the winding start part of the high stage side fixed tooth part 13b, when the movable scroll 11 revolves, the winding start part of the high stage side movable side tooth part 11c comes into contact with the high stage side compression chamber VH. Thus, it is formed in a substantially oval shape capable of compressing the refrigerant. FIG. 11 is a drawing corresponding to FIG. 7 of the first embodiment. Other configurations and operations are the same as those in the first embodiment.

  Therefore, also in the compressor 1 of this embodiment, the effect similar to 1st Embodiment can be acquired. Furthermore, in the present embodiment, the tip end curve Ic is formed in a semi-elliptical shape, so the curvature of the portion of the tip end curve Ic that is in contact with the higher-stage fixed-side tooth portion 13b is very easily increased. It can be made smaller than the curvature of the arc whose diameter is the maximum value Ti of the radial thickness dimension T of the movable side tooth portion 11c.

(Third embodiment)
This embodiment demonstrates the example which changed the radial direction thickness dimension T of the low stage side movable side tooth part 11b and the high stage side movable side tooth part 11c with respect to 1st Embodiment. In the present embodiment, the same effect can be obtained by both the low-stage compression mechanism and the high-stage compression mechanism, and therefore, in the following description, the high-stage compression mechanism will be described as an example.

  Specifically, the high-stage movable side tooth portion 11 c of the present embodiment has a radial thickness dimension T that gradually increases from the outer peripheral side toward the center side of the shaft 25. That is, as shown in FIG. 12, the radial thickness dimension Ti on the center side of the shaft 25 is formed larger than the radial thickness dimension To on the outer peripheral side.

  FIG. 12 is a drawing corresponding to FIG. 5 of the first embodiment. The radial thickness dimension T is a radial distance between the outer circumferential involute curve Io and the inner circumferential involute curve Ii. Other configurations and operations are the same as those in the first embodiment.

  Therefore, also in the compressor 1 of this embodiment, the effect similar to 1st Embodiment can be acquired. Further, in the present embodiment, the radial thickness dimension Ti on the central side that forms the high-stage compression chamber VH having a higher pressure than the outer peripheral side of the high-stage movable side tooth portion 1c is set to the radial thickness on the outer peripheral side. It is formed larger than the dimension To. Therefore, the radial deformation of the high stage movable side tooth portion 1c can be suppressed, and the airtightness of the high stage compression chamber VH can be further effectively improved.

(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 each of the above-described embodiments, the scroll compressor 1 according to the present invention has been described as being configured as a multistage booster compressor. However, of course, it may be configured as a single-stage booster compressor. Furthermore, when configuring as a multistage booster compressor, the movable side teeth described in the above embodiments may be applied to all the compression mechanisms or at least one.

In addition, the multistage boost type scroll compressor 1 described in each of the above-described embodiments is provided.
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.

  (2) In each of the above-described embodiments, the example in which the scroll compressor 1 according to the present invention is applied to the refrigeration cycle 100 has been described. However, the application of the scroll compressor 1 is not limited thereto. 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.

  (3) 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. Then, 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.

  (4) In the first embodiment described above, the example has been described in which the tip curve Ic has a shape formed by combining two arcs having different diameters, but the tip curve Ic has a shape formed by strictly combining two arcs. It is not limited to what has become. For example, the tip end curve Ic may be slightly deviated from a combination of two arcs having different diameters by chamfering the connection portion. The same applies to the semi-elliptical shape of the second embodiment.

  (5) The means disclosed in each of the above embodiments may be appropriately combined within a practicable range. For example, in the movable scroll 11 described in the second embodiment, the radial thickness dimension T of the low stage side movable side tooth part 11b and the high stage side movable side tooth part 11c may be changed as in the third embodiment. .

11 movable scroll 11b, 11c low stage side movable tooth part, high stage side movable tooth part 12, 13 low stage side fixed scroll, high stage side fixed scroll 12b, 13b low stage side fixed tooth part, high stage side fixed tooth part Io Outer circumference involute curve Ii Inner circumference involute curve Ic Tip curve T Radial thickness

Claims (3)

A rotating shaft (25) that rotates by obtaining a driving force from a rotational driving source (10);
The revolving motion is caused by the rotational driving force transmitted from the rotating shaft (25), and the plate-shaped movable side substrate portion (11a) and the movable side substrate portion (11a) in the axial direction of the rotating shaft (25). A movable scroll (11) having a spiral movable side tooth portion (11c) protruding;
A flat plate-like fixed-side substrate portion (13a), and a spiral fixed-side tooth portion protruding from the fixed-side substrate portion (13a) in the axial direction of the rotating shaft (25) and meshing with the movable-side tooth portion (11c). A fixed scroll (13) having (13b),
The rotating shaft (25) passes through the movable side substrate (11a),
The space formed between the movable side tooth portion (11c) and the fixed side tooth portion (13b) changes in volume by the revolving motion of the movable scroll (11) and pressurizes the fluid to be compressed. Forming a chamber (VH),
The involute curve drawn by the outer peripheral wall surface of the movable side tooth portion (11c) in the axial vertical section of the rotating shaft (25) is defined as the outer peripheral side involute curve (Io), and the inner periphery of the movable side tooth portion (11c). The involute curve drawn by the wall surface is defined as an inner circumference side involute curve (Ii), and the rotation axis side end of the outer circumference side involute curve (Io) and the rotation axis side end of the inner circumference side involute curve (Ii) are connected. When the curve is the tip curve (Ic),
The tip curve (Ic) is a combination of two arcs with different diameters,
The diameter of the outer circumference side arc (MCo) connected to the outer circumference side involute curve (Io) is smaller than the diameter of the inner circumference side arc (Ci) connected to the inner circumference side involute curve (Ii). ,
When the movable scroll (11) is displaced to a position where the compression chamber (VH) having the minimum volume is formed, a curvature of a portion of the tip curve (Ic) that contacts the fixed side tooth portion (13b) is: The scroll compressor characterized by being formed smaller than the curvature of the circular arc whose diameter is the maximum value (Ti) of the radial thickness dimension (T) of the movable side tooth portion (11c). A rotating shaft (25) that rotates by obtaining a driving force from a rotational driving source (10);
The revolving motion is caused by the rotational driving force transmitted from the rotating shaft (25), and the plate-shaped movable side substrate portion (11a) and the movable side substrate portion (11a) in the axial direction of the rotating shaft (25). A movable scroll (11) having a spiral movable side tooth portion (11c) protruding;
A flat plate-like fixed-side substrate portion (13a), and a spiral fixed-side tooth portion protruding from the fixed-side substrate portion (13a) in the axial direction of the rotating shaft (25) and meshing with the movable-side tooth portion (11c). A fixed scroll (13) having (13b),
The rotating shaft (25) passes through the movable side substrate (11a),
The space formed between the movable side tooth portion (11c) and the fixed side tooth portion (13b) changes in volume by the revolving motion of the movable scroll (11) and pressurizes the fluid to be compressed. Forming a chamber (VH),
The involute curve drawn by the outer peripheral wall surface of the movable side tooth portion (11c) in the axial vertical section of the rotating shaft (25) is defined as the outer peripheral side involute curve (Io), and the inner periphery of the movable side tooth portion (11c). The involute curve drawn by the wall surface is defined as an inner circumference side involute curve (Ii), and the rotation axis side end of the outer circumference side involute curve (Io) and the rotation axis side end of the inner circumference side involute curve (Ii) are connected. When the curve is the tip curve (Ic),
The tip curve (Ic) is formed in a semi-elliptical shape with the minor axis of the radial thickness dimension (Ti) of the movable side tooth portion (11c),
When the movable scroll (11) is displaced to a position where the compression chamber (VH) having the minimum volume is formed, a curvature of a portion of the tip curve (Ic) that contacts the fixed side tooth portion (13b) is: The scroll compressor characterized by being formed smaller than the curvature of the circular arc whose diameter is the maximum value (Ti) of the radial thickness dimension (T) of the movable side tooth portion (11c). Radial thickness of the movable-side tooth portion (11c) (T) is according to claim 1 or 2, characterized in that gradually increases toward the center side of the rotary shaft (25) from the outer circumferential side Scroll compressor.

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