JP2017186924A - Compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compressor which suppresses lowering of efficiency of a motor.SOLUTION: A scroll compressor 10 includes: a casing 20; a suction pipe 23; a scroll compression mechanism 60; a drive motor 70; a discharge pipe 24; a bypass pipe 110; and a solenoid valve 130. The suction pipe is connected to the casing. The scroll compression mechanism 60 is arranged in the casing 20 and the drive motor 70 is arranged in a motor storage space in the casing 20. The discharge pipe 24 discharges coolant after compression from the motor storage space. The bypass pipe 110 forms a bypass flow passage which bypasses the coolant after compression to the discharge pipe 24 without passing though the motor storage space. The solenoid valve 130 closes a passage to the bypass flow passage when a compression ratio of the coolant is within a first range and opens the passage to the bypass flow passage when the compression ratio is within a second range in which the compression ratio is smaller than the first range.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a compressor.

  A compressor is known in which the sucked refrigerant is compressed in a compression chamber, and the compressed refrigerant is guided to a space in which a motor is disposed, and then discharged to the outside through a discharge pipe (Patent Document 1 (Japanese Patent Laid-Open No. 2000-2000)). -97172)).

  This type of compressor cools the motor by guiding the compressed refrigerant to a space in which the motor is disposed. However, depending on the compression ratio of the refrigerant, the motor may be heated instead by introducing the compressed refrigerant into the space where the motor is arranged. When the motor is warmed, the efficiency of the motor is reduced.

  The subject of this invention is providing the compressor which suppresses the fall of the efficiency of a motor.

  A compressor according to a first aspect of the present invention includes a casing, a suction pipe, a compression mechanism, a motor, a discharge pipe, a bypass member, and an on-off valve. The suction pipe is connected to the casing. The suction pipe sucks the refrigerant. The compression mechanism is disposed in the casing. The compression mechanism compresses the refrigerant. The motor is arranged in a motor housing space in the casing. The motor drives the compression mechanism. The discharge pipe is connected to the casing. The discharge pipe discharges the compressed refrigerant from the motor housing space. The bypass member forms a bypass flow path that bypasses the refrigerant during or after compression to the discharge pipe without passing through the motor housing space. The on-off valve closes the passage to the bypass channel when the refrigerant compression ratio is within the first range. The on-off valve opens the passage to the bypass flow path when the compression ratio is in the second range where the compression ratio is smaller than the first range.

  In the compressor according to the first aspect of the present invention, the on-off valve closes the passage to the bypass flow path when the refrigerant compression ratio is within the first range. In this case, since the compressed refrigerant is guided to the motor housing space, the motor can be cooled by the compressed refrigerant. On the other hand, the on-off valve opens the passage to the bypass channel when the compression ratio of the refrigerant is within the second range. In this case, since the refrigerant in the middle of compression or after compression is guided not to the motor housing space but to the bypass flow path, the heating of the motor by the refrigerant is suppressed. Therefore, a reduction in motor efficiency can be suppressed.

  In the compressor according to the second aspect of the present invention, the bypass member is a bypass pipe. One end of the bypass member is connected to the discharge pipe. The other end of the bypass member is connected to a flow path from the refrigerant discharge space leading to the compression chamber of the compression mechanism to the motor housing space. The on-off valve is an electromagnetic valve or an electric valve attached to the bypass member.

  In the compressor according to the second aspect of the present invention, it is possible to suppress a reduction in the efficiency of the motor by a simple configuration in which an on-off valve is attached to the bypass member.

  The compressor according to the third aspect of the present invention further includes a chamber cover. The chamber cover forms a refrigerant discharge space. The chamber cover has an opening. The other end of the bypass member is connected to the opening.

  In the compressor which concerns on the 3rd viewpoint of this invention, the fall of the efficiency of a motor can be suppressed by the simple structure of attaching the other end of a bypass member to a chamber cover.

  In the compressor according to the fourth aspect of the present invention, the compression mechanism is formed with a bypass hole through which the refrigerant being compressed passes. The bypass member is a bypass pipe. One end of the bypass member is connected to the discharge pipe. The other end of the bypass member is connected to the bypass hole. The on-off valve is attached to the bypass member. The on-off valve is a check valve that opens and closes due to the difference between the pressure from the bypass hole and the pressure on the bypass pipe side.

  In the compressor according to the fourth aspect of the present invention, the on-off valve opens and closes due to the difference between the pressure from the bypass hole and the pressure on the bypass piping side, so that the motor efficiency is reduced without electrical control of the on-off valve. Can be suppressed.

  In the compressor according to the fifth aspect of the present invention, in addition to the bypass hole, the compression mechanism is formed with a relief hole through which the refrigerant being compressed passes. The relief hole communicates with the refrigerant discharge space that communicates with the compression chamber of the compression mechanism. The compressor according to the fifth aspect of the present invention further includes a relief valve. The relief valve is attached so as to cover the relief hole. The relief valve is a check valve that opens and closes due to the difference between the pressure from the relief hole and the pressure in the refrigerant discharge space.

  In the compressor according to the fifth aspect of the present invention, the relief valve opens and closes due to the difference between the pressure from the relief hole and the pressure in the refrigerant discharge space, so that excessive compression by the compression mechanism can be prevented. That is, it is possible to achieve both suppression of reduction in motor efficiency and prevention of overcompression.

  The compressor concerning the 6th viewpoint of the present invention is further provided with a chamber cover, a partition member, and a relief valve. The chamber cover forms a refrigerant discharge space that communicates with the compression chamber of the compression mechanism. The partition member divides the refrigerant discharge space into a first space and a second space having a lower pressure than the first space. A discharge hole for discharging the compressed refrigerant is formed in a portion of the compression mechanism included in the first space. A bypass hole for discharging the refrigerant being compressed is formed in a portion of the compression mechanism included in the second space. The bypass member is a bypass pipe. One end of the bypass member is connected to the discharge pipe. The other end of the bypass member is connected to the second space. The relief valve is attached so as to cover the bypass hole. The relief valve is a check valve that opens and closes due to the difference between the pressure from the bypass hole and the pressure in the second space.

  In the compressor which concerns on the 6th viewpoint of this invention, the fall of the efficiency of a motor can be suppressed by providing the 2nd space in which the refrigerant | coolant in the middle of compression is discharged in a refrigerant | coolant discharge space.

  In the compressor according to the present invention, when the compression ratio of the refrigerant is within the second range, the on-off valve opens the passage to the bypass flow path, so that heating of the motor by the refrigerant is suppressed. Therefore, a reduction in motor efficiency can be suppressed.

It is a schematic diagram of an air harmony device. It is a longitudinal cross-sectional view of the scroll compressor of 1st Embodiment. It is a conceptual diagram which shows the relationship between the temperature of a stator and the temperature of the refrigerant | coolant after compression. It is a longitudinal cross-sectional view of the scroll compressor of 2nd Embodiment. It is a partial enlarged view of the scroll compressor of 2nd Embodiment. It is a partial longitudinal cross-sectional view of the scroll compressor of 3rd Embodiment. It is a top view of the fixed scroll seen from the perpendicular direction upper part. It is a partial longitudinal cross-sectional view of the scroll compressor of 4th Embodiment.

  Embodiments of the present invention are shown below. The following embodiments are merely specific examples and do not limit the invention according to the claims.

<First Embodiment>
(1) Configuration of Air Conditioner FIG. 1 is a schematic diagram of an air conditioner 1 including a scroll compressor 10 as an example of a compressor according to the present invention. In the present embodiment, the air conditioner 1 is dedicated to the cooling operation. The air conditioner 1 may be dedicated to the heating operation, or may be used for both the cooling operation and the heating operation.

  The air conditioner 1 mainly includes an outdoor unit 2, an indoor unit 3, a liquid refrigerant communication pipe 4, and a gas refrigerant communication pipe 5. The refrigerant circuit 100 of the air conditioner 1 includes an outdoor unit 2, an indoor unit 3, a liquid refrigerant communication pipe 4, and a gas refrigerant communication pipe 5.

  The outdoor unit 2 mainly includes an accumulator 6, an outdoor heat exchanger 7, an expansion valve 8, an economizer heat exchanger 9, a scroll compressor 10, an injection valve 26, and an outdoor side control unit 28.

  The accumulator 6 is provided in a pipe connecting the gas refrigerant communication pipe 5 and the suction pipe 23 of the scroll compressor 10. The accumulator 6 divides the refrigerant into a gas phase and a liquid phase.

  The outdoor heat exchanger 7 is a cross-fin type fin-and-tube heat exchanger composed of heat transfer tubes and a large number of heat transfer fins. One of the outdoor heat exchangers 7 is connected to the discharge pipe 24 side through which the refrigerant discharged from the scroll compressor 10 flows, and the other of the outdoor heat exchangers 7 is connected to the liquid refrigerant communication pipe 4 side. The outdoor heat exchanger 7 functions as a refrigerant condenser.

  The expansion valve 8 is provided in a pipe connecting the outdoor heat exchanger 7 and the liquid refrigerant communication pipe 4. The expansion valve 8 is an electric valve whose opening degree can be adjusted for adjusting the pressure and flow rate of the refrigerant flowing through the pipe.

  The economizer heat exchanger 9 is disposed between the outdoor heat exchanger 7 and the expansion valve 8. The economizer heat exchanger 9 performs heat exchange between the refrigerant that flows from the outdoor heat exchanger 7 toward the expansion valve 8 and the refrigerant that flows through the injection refrigerant supply pipe 27 and is decompressed by the injection valve 26.

  The scroll compressor 10 compresses and discharges the refrigerant circulating in the refrigerant circuit 100. More specifically, the refrigerant sucked through the suction pipe 23 is compressed in a compression chamber Sc described later, and the compressed refrigerant is discharged from the discharge pipe 24. In the scroll compressor 10, so-called intermediate injection is performed in which a part of the refrigerant flowing from the outdoor heat exchanger 7 toward the expansion valve 8 is supplied to the compression chamber Sc being compressed.

  The injection valve 26 is an electric valve with an adjustable opening for adjusting the pressure and flow rate of refrigerant injected into the scroll compressor 10. The injection valve 26 is provided in an injection refrigerant supply pipe 27 branched from a pipe connecting the outdoor heat exchanger 7 and the expansion valve 8. The injection refrigerant supply pipe 27 is a pipe that supplies a refrigerant to the injection pipe 25 of the scroll compressor 10.

  The outdoor side control unit 28 includes a microcomputer, a memory, and the like. The outdoor side control unit 28 controls the operation of each unit constituting the outdoor unit 2. In particular, in the present embodiment, the outdoor side control unit 28 controls the opening and closing of a solenoid valve 130 described later provided in the scroll compressor 10. Specifically, when the compression ratio of the refrigerant is within the first range, the electromagnetic valve 130 is controlled so as to close a passage to a bypass flow path described later. When the compression ratio is in the second range where the compression ratio is smaller than the first range, the solenoid valve 130 is controlled to open the passage to the bypass flow path. The refrigerant compression ratio depends on the rotational speed of a drive motor 70 described later. Therefore, if the relationship between the compression ratio and the rotation speed of the drive motor 70 is derived in advance through experiments or simulations, the outdoor control unit 28 controls the electromagnetic valve 130 based on the rotation speed of the drive motor 70. be able to. Moreover, the outdoor side control part 28 communicates a control signal etc. between the below-mentioned indoor side control parts 3b.

  The indoor unit 3 mainly includes an indoor heat exchanger 3a and an indoor side control unit 3b. The indoor heat exchanger 3a is a cross-fin type fin-and-tube heat exchanger composed of heat transfer tubes and a large number of fins. One of the indoor heat exchangers 3 a is connected to the liquid refrigerant communication pipe 4, and the other of the indoor heat exchangers 3 a is connected to the gas refrigerant communication pipe 5. The indoor heat exchanger 3a functions as a refrigerant evaporator.

  The indoor side control part 3b is comprised from the microcomputer, the memory, etc. The indoor side control unit 3 b controls the operation of each unit constituting the indoor unit 3. The indoor side control unit 3 b communicates control signals and the like with the outdoor side control unit 28.

  The liquid refrigerant communication pipe 4 and the gas refrigerant communication pipe 5 connect the outdoor unit 2 and the indoor unit 3.

(2) Configuration of Scroll Compressor FIG. 2 is a longitudinal sectional view of the scroll compressor 10. The scroll compressor 10 includes a casing 20, a scroll compression mechanism 60 including a fixed scroll 30, a drive motor 70, a crankshaft 80, a lower bearing 90, a bypass pipe 110, a chamber cover 120, and a solenoid valve 130. Is provided. Moreover, the scroll compressor 10 is provided with the non-return valve 50 and the injection piping 25 as FIG. 2 shows. The check valve 50 is provided in an injection passage 31 formed in the fixed scroll 30. The injection pipe 25 supplies a refrigerant to the injection passage 31.

  In the following description, expressions such as “up” and “down” may be used to describe the positional relationship of the constituent members, but here, the direction of the arrow U in FIG. The direction opposite to the arrow U is denoted as “down”. In the following description, expressions such as “vertical”, “horizontal”, “vertical”, “horizontal” may be used, but the vertical direction is defined as the vertical direction and the vertical direction.

(2-1) Casing The scroll compressor 10 has a vertically long cylindrical casing 20. The casing 20 includes a substantially cylindrical cylindrical member 21 that is open at the top and bottom, and an upper lid 22 a and a lower lid 22 b provided at the upper end and the lower end of the cylindrical member 21, respectively. The cylindrical member 21, and the upper lid 22a and the lower lid 22b are fixed by welding so as to keep airtightness.

  The casing 20 accommodates components of the scroll compressor 10 including the scroll compression mechanism 60, the drive motor 70, the crankshaft 80, and the lower bearing 90. An oil sump space So is formed in the lower part of the casing 20. Refrigerating machine oil O for lubricating the scroll compression mechanism 60 and the like is stored in the oil reservoir space So.

  A suction pipe 23 is connected to the upper part of the casing 20. Specifically, the suction pipe 23 is provided through the upper lid 22a. The suction pipe 23 sucks the gas refrigerant and supplies the gas refrigerant to the scroll compression mechanism 60. The lower end of the suction pipe 23 is connected to the fixed scroll 30 of the scroll compression mechanism 60. The suction pipe 23 communicates with the compression chamber Sc of the scroll compression mechanism 60. The low-pressure refrigerant in the refrigeration cycle before compression by the scroll compression mechanism 60 flows through the suction pipe 23.

  A discharge pipe 24 is connected to an intermediate portion of the cylindrical member 21 of the casing 20. Specifically, the discharge pipe 24 is disposed so that the end of the discharge pipe 24 inside the casing 20 protrudes into the high-pressure space S <b> 1 formed below the housing 61 of the scroll compression mechanism 60. The discharge pipe 24 discharges the refrigerant compressed by the scroll compression mechanism 60 out of the casing 20 from the motor housing space S2 in which the drive motor 70 is housed. The discharge pipe 24 allows the refrigerant discharged outside the casing 20 to pass through. More specifically, the discharge pipe 24 passes the high-pressure refrigerant in the refrigeration cycle after being compressed by the scroll compression mechanism 60.

(2-2) Scroll Compression Mechanism The scroll compression mechanism 60 mainly includes a housing 61, a fixed scroll 30 disposed above the housing 61, and a movable scroll 40 that is combined with the fixed scroll 30 to form a compression chamber Sc. And have. The scroll compression mechanism 60 compresses the refrigerant.

(2-2-1) Fixed Scroll The fixed scroll 30 includes a flat fixed side end plate 32, a spiral fixed side wrap 33 protruding from the front surface of the fixed side end plate 32 (ie, the lower surface in FIG. 2), and a fixed scroll. And an outer edge portion 34 surrounding the side wrap 33.

  A non-circular discharge hole 32 a communicating with the compression chamber Sc of the scroll compression mechanism 60 is formed in the center of the fixed side end plate 32 so as to penetrate the fixed side end plate 32 in the thickness direction. The refrigerant compressed in the compression chamber Sc is discharged from the discharge hole 32a, passes through a refrigerant passage (not shown) formed in the fixed scroll 30 and the housing 61, and flows into the high-pressure space S1.

  The fixed side end plate 32 is formed with an injection passage 31 that opens on the side surface of the fixed side end plate 32 and communicates with the compression chamber Sc. The intermediate pressure refrigerant is supplied to the compression chamber Sc through the injection passage 31.

(2-2-2) Movable Scroll The movable scroll 40 includes a flat movable side end plate 41, a spiral movable side wrap 42 that protrudes from the front surface of the movable side end plate 41 (ie, the upper surface in FIG. 2), and a movable scroll. It has a cylindrical boss portion 43 that protrudes from the back surface of the side end plate 41 (that is, the lower surface in FIG. 2).

  The fixed side wrap 33 of the fixed scroll 30 and the movable side wrap 42 of the movable scroll 40 are combined in a state where the lower surface of the fixed side end plate 32 and the upper surface of the movable side end plate 41 face each other. A compression chamber Sc is formed between the adjacent fixed side wrap 33 and the movable side wrap 42. As the movable scroll 40 revolves with respect to the fixed scroll 30 as will be described later, the volume of the compression chamber Sc changes periodically. In the scroll compression mechanism 60, refrigerant is sucked, compressed, and discharged.

  The boss portion 43 is a cylindrical portion whose upper end is blocked. The movable scroll 40 and the crankshaft 80 are connected to each other by inserting an eccentric portion 81 of the crankshaft 80 described later into the hollow portion of the boss portion 43. The boss portion 43 is disposed in an eccentric portion space 62 formed between the movable scroll 40 and the housing 61. The eccentric portion space 62 communicates with the high-pressure space S1 via an oil supply path 83 of the crankshaft 80 described later. A high pressure acts on the eccentric part space 62. With this pressure, the lower surface of the movable side end plate 41 in the eccentric portion space 62 is pushed upward toward the fixed scroll 30. Due to this force, the movable scroll 40 comes into close contact with the fixed scroll 30.

  The movable scroll 40 is supported by the housing 61 via the Oldham ring 58. The Oldham ring 58 is a member that prevents the movable scroll 40 from rotating and revolves. When the crankshaft 80 rotates by using the Oldham ring 58, the movable scroll 40 connected to the crankshaft 80 in the boss portion 43 revolves without rotating with respect to the fixed scroll 30, and the refrigerant in the compression chamber Sc. Is compressed.

(2-2-3) Housing The housing 61 is press-fitted into the cylindrical member 21, and is fixed to the cylindrical member 21 over the entire circumferential direction on the outer peripheral surface thereof. Further, the housing 61 and the fixed scroll 30 are fixed by a bolt or the like (not shown) so that the upper end surface of the housing 61 is in close contact with the lower surface of the outer edge portion 34 of the fixed scroll 30.

  The housing 61 is formed with a recessed portion 61a disposed so as to be recessed in the central portion of the upper surface and a bearing portion 61b disposed below the recessed portion 61a.

  The recessed part 61a surrounds the side surface of the eccentric part space 62 in which the boss part 43 of the movable scroll 40 is disposed.

  A bearing 63 that pivotally supports the main shaft 82 of the crankshaft 80 is disposed in the bearing portion 61b. The bearing 63 rotatably supports the main shaft 82 inserted into the bearing 63.

(2-3) Drive Motor The drive motor 70 is disposed in the motor housing space S <b> 2 in the casing 20. The motor housing space S <b> 2 is a space below the scroll compression mechanism 60. The drive motor 70 drives the scroll compression mechanism 60. The drive motor 70 includes an annular stator 71 fixed to the inner wall surface of the cylindrical member 21, and a rotor 72 that is rotatably accommodated inside the stator 71 with a slight gap (air gap passage).

  The rotor 72 is connected to the movable scroll 40 via a crankshaft 80 disposed so as to extend in the vertical direction along the axial center of the cylindrical member 21. As the rotor 72 rotates, the movable scroll 40 revolves with respect to the fixed scroll 30.

(2-4) Crankshaft The crankshaft 80 transmits the driving force of the drive motor 70 to the movable scroll 40. The crankshaft 80 is disposed so as to extend in the vertical direction along the axial center of the cylindrical member 21, and connects the rotor 72 of the drive motor 70 and the movable scroll 40 of the scroll compression mechanism 60.

  The crankshaft 80 includes a main shaft 82 whose center axis coincides with the axis of the cylindrical member 21, and an eccentric portion 81 that is eccentric with respect to the axis of the cylindrical member 21. The eccentric portion 81 is inserted into the boss portion 43 of the movable scroll 40 as described above. The main shaft 82 is rotatably supported by a bearing 63 of the bearing portion 61b of the housing 61 and a lower bearing 90 described later. The main shaft 82 is connected to the rotor 72 of the drive motor 70 between the bearing portion 61 b and the lower bearing 90.

  An oil supply path 83 for supplying the refrigerator oil O to the scroll compression mechanism 60 and the like is formed inside the crankshaft 80. The lower end of the main shaft 82 is located in an oil sump space So formed in the lower part of the casing 20. The refrigerating machine oil O in the oil reservoir space So is supplied to the scroll compression mechanism 60 and the like through the oil supply path 83.

(2-5) Lower Bearing The lower bearing 90 is disposed below the drive motor 70. The lower bearing 90 is fixed to the cylindrical member 21. The lower bearing 90 constitutes a bearing on the lower end side of the crankshaft 80 and rotatably supports the main shaft 82 of the crankshaft 80.

(2-6) Bypass piping The bypass piping 110 as an example of a bypass member forms a bypass flow path. The bypass channel is a channel that bypasses the compressed refrigerant to the discharge pipe 24 without passing through the motor housing space S2. One end of the bypass pipe 110 is connected to the discharge pipe 24. The other end of the bypass pipe 110 is connected to a flow path from the refrigerant discharge space S3 to the motor housing space S2. In the present embodiment, it is connected to the chamber cover 120. The refrigerant discharge space S3 is a space that communicates with the compression chamber Sc of the scroll compression mechanism 60. The refrigerant discharge space S3 is a space sandwiched between the chamber cover 120 and the fixed scroll 30.

(2-7) Chamber cover The chamber cover 120 forms the refrigerant discharge space S3. The chamber cover 120 has an opening. The other end of the bypass pipe 110 is connected to the opening.

(2-8) Electromagnetic valve The electromagnetic valve 130 as an example of the on-off valve is attached to the bypass pipe 110. The solenoid valve 130 closes the passage to the bypass flow path when the refrigerant compression ratio is within the first range. The solenoid valve 130 opens the passage to the bypass flow path when the refrigerant compression ratio is within the second range. Here, the compression ratio in the second range is smaller than the compression ratio in the first range.

(3) Relationship Between Stator Temperature and Compressed Refrigerant Temperature FIG. 3 is a conceptual diagram showing a relationship between the stator 71 temperature and the compressed refrigerant temperature. The horizontal axis represents the refrigerant compression ratio, and the vertical axis represents the temperature. A straight line m indicated by a solid line indicates the temperature of the stator 71, and a straight line g indicated by a two-dot chain line indicates the temperature of the refrigerant after compression. Point P1 shows the minimum value that the compression ratio can take, and point P2 shows the maximum value that the compression ratio can take. Point P3 is the intersection of line m and line g. The range r1 indicates the first range of the compression ratio described above, and the range r2 indicates the second range of the compression ratio described above.

  When the compression ratio is larger than the compression ratio at the point P3, that is, when the compression ratio is in the range r1, the temperature of the stator 71 is higher than the temperature of the refrigerant after compression. The temperature difference between the temperature of the stator 71 and the temperature of the compressed refrigerant increases as the compression ratio increases.

  When the compression ratio is smaller than the compression ratio at the point P3, that is, when the compression ratio is in the range r2, the temperature of the stator 71 is lower than the temperature of the refrigerant having the degree of compression. Then, the temperature difference between the temperature of the stator 71 and the temperature of the refrigerant after compression increases as the compression ratio decreases.

  From the above, the solenoid valve 130 closes the passage to the bypass flow path when the compression ratio is within the range r1. Thereby, the drive motor 70 can be cooled with the refrigerant | coolant after compression. On the other hand, when the compression ratio of the refrigerant is within the second range, the passage to the bypass channel is opened. Thereby, the heating of the drive motor 70 by the compressed refrigerant is suppressed. Therefore, a decrease in the efficiency of the drive motor 70 can be suppressed.

(4) Operation of Scroll Compressor When the drive motor 70 is driven, the rotor 72 rotates with respect to the stator 71. As a result, the crankshaft 80 fixed to the rotor 72 rotates. When the crankshaft 80 rotates, the movable scroll 40 connected to the crankshaft 80 revolves with respect to the fixed scroll 30. Then, the low-pressure gas refrigerant (that is, the refrigerant before compression) in the refrigeration cycle passes through the suction pipe 23 and is sucked into the compression chamber Sc from the peripheral side of the compression chamber Sc. As the movable scroll 40 revolves, the suction pipe 23 and the compression chamber Sc no longer communicate with each other, and the pressure in the compression chamber Sc starts to increase as the volume of the compression chamber Sc decreases. Note that the refrigerant is injected into the compression chamber Sc in the middle of compression from the injection port 31a.

  The compression chamber Sc does not communicate with the injection port 31a as the refrigerant is compressed. The refrigerant in the compression chamber Sc is compressed as the volume of the compression chamber Sc decreases, and finally becomes a high-pressure gas refrigerant (that is, a refrigerant after compression).

  The compressed refrigerant is discharged into the refrigerant discharge space S3 from the discharge hole 32a located near the center of the fixed side end plate 32. Thereafter, when the compression ratio of the refrigerant is within the first range, the compressed refrigerant is guided to the motor housing space S2. The compressed refrigerant is discharged to the outside of the scroll compressor 10 from the motor housing space S <b> 2 via the discharge pipe 24 after cooling the drive motor 70. On the other hand, when the compression ratio of the refrigerant is within the second range, the compressed refrigerant is guided to the bypass pipe 110 instead of the motor housing space S2. The compressed refrigerant is discharged from the bypass pipe 110 to the outside of the scroll compressor 10 via the discharge pipe 24.

(5) Features of Scroll Compressor The scroll compressor 10 of this embodiment includes a bypass pipe 110 and an electromagnetic valve 130. The bypass pipe 110 forms a bypass flow path that bypasses the compressed refrigerant to the discharge pipe 24 without passing through the motor housing space S2.

  As shown in FIG. 3, when the compression ratio is in the range r1, that is, in the first range, the temperature of the stator 71 is higher than the temperature of the refrigerant after compression. Therefore, in this case, the solenoid valve 130 closes the passage to the bypass flow path. If it does so, since the refrigerant | coolant after compression is guide | induced to motor accommodation space S2, the drive motor 70 can be cooled with the refrigerant | coolant after compression.

  On the other hand, when the compression ratio is in the range r2, that is, in the second range, the temperature of the stator 71 is lower than the temperature of the refrigerant after compression. Here, even in this case, if the compressed refrigerant is guided to the motor housing space S2, the drive motor 70 is heated by the compressed refrigerant. In the present embodiment, the electromagnetic valve 130 opens the passage to the bypass flow path when the compression ratio is within the second range. If it does so, since the refrigerant | coolant after compression is mainly led not to motor accommodation space S2, but to bypass piping 110, the heating of the drive motor 70 by the refrigerant | coolant after compression is suppressed. Therefore, a decrease in the efficiency of the drive motor 70 can be suppressed.

  The scroll compressor 10 of this embodiment is provided with the bypass piping 110 and the solenoid valve 130 as already demonstrated. The electromagnetic valve 130 is attached to the bypass pipe 110. With a simple configuration in which the electromagnetic valve 130 is attached to the bypass pipe 110, a decrease in the efficiency of the drive motor 70 can be suppressed.

  The scroll compressor 10 of this embodiment includes a chamber cover 120. The other end of the bypass pipe 110 is connected to the opening of the chamber cover 120. With a simple configuration in which the other end of the bypass pipe 110 is attached to the chamber cover 120, a decrease in the efficiency of the drive motor 70 can be suppressed.

<Modification>
A modification applicable to the embodiment of the present invention will be described.

(1) Modification A
In the above description, the electromagnetic valve 130 is taken as an example of the on-off valve, but the on-off valve may be an electric valve. In this case, the outdoor control unit 28 can control the opening / closing of the on-off valve more finely according to the rotational speed of the drive motor 70.

Second Embodiment
FIG. 4 is a longitudinal sectional view of the scroll compressor 10 of the second embodiment. FIG. 5 is a partially enlarged view of the scroll compressor 10 of the second embodiment. Specifically, it is an enlarged view of the other end of the bypass pipe 110 (on the fixed side end plate 32 side) and its periphery. Here, differences from the scroll compressor 10 of the first embodiment will be mainly described. The same reference numerals are used for elements having the same structure and function as the scroll compressor 10 of the first embodiment.

(1) Configuration of Scroll Compressor (1-1) Fixed Scroll As already described, a discharge hole 32a is formed in the central portion of the fixed side end plate 32 of the fixed scroll 30. In the present embodiment, a bypass hole 32 b is further formed on the left side from the center of the fixed side end plate 32. The bypass hole 32 b is a hole that communicates with the compression chamber Sc of the scroll compression mechanism 60. The bypass hole 32b penetrates the fixed side end plate 32 in the thickness direction. The bypass hole 32b passes the refrigerant in the middle of compression.

(1-2) Bypass piping As already described, the bypass piping 110 as an example of a bypass member forms a bypass flow path. One end of the bypass pipe 110 is connected to the discharge pipe 24. The other end of the bypass pipe 110 is connected to a flow path from the refrigerant discharge space S3 to the motor housing space S2. In this embodiment, it is connected to the bypass hole 32b. In more detail, it arrange | positions so that the fixed side end plate 32 may be touched and the bypass hole 32b may be enclosed.

(1-3) Check Valve In this embodiment, the check valve 140 is used instead of the solenoid valve 130 as an example of the on-off valve. The check valve 140 is attached to the bypass pipe 110. More specifically, the check valve 140 is provided in the bypass channel. The check valve 140 opens and closes due to the difference between the pressure from the bypass hole 32b and the pressure on the bypass pipe 110 side. More specifically, the refrigerant flow is not blocked when the pressure from the bypass hole 32b is higher than the pressure on the bypass pipe 110 side. That is, the passage to the bypass channel is opened. In the present embodiment, when the compression ratio of the refrigerant is within the second range, the passage to the bypass channel is configured to be opened. In this case, the refrigerant flows from the bypass hole 32b to the bypass pipe 110.

  On the other hand, when the pressure from the bypass hole 32b is equal to or lower than the pressure on the bypass pipe 110 side, the refrigerant flow is blocked. That is, the passage to the bypass channel is closed. In the present embodiment, when the compression ratio of the refrigerant is within the first range, the passage to the bypass flow path is closed. In this case, the refrigerant does not flow from the bypass hole 32b to the bypass pipe 110.

  The positions, sizes, and the like of the bypass hole 32b and the check valve 140 are determined so as to realize the refrigerant flow as described above. The check valve 140 mainly includes a valve main body 51, a first valve pressing member 52, and a second valve pressing member 53.

(1-3-1) Valve Body The valve body 51 is a thin circular flat plate. A circular central hole 51 a is formed in the central portion of the valve body 51. The valve main body 51 mainly has an annular peripheral portion 51b that is disposed on the peripheral side of the central hole 51a.

  The central hole 51a formed in the valve body 51 is a hole through which the refrigerant passes when the refrigerant flows from the bypass hole 32b to the bypass pipe 110. The valve body 51 is disposed at the end of the bypass channel. Specifically, the valve main body 51 includes a first valve pressing member 52 that is press-fitted into the end of the bypass flow path, and a second valve pressing member 53 that is press-fitted at a position away from the first valve pressing member 52. Located in the sandwiched area. The valve body 51 is slidably disposed in the above-described area.

(1-3-2) First valve pressing member The first valve pressing member 52 is a circular flat plate having a thickness greater than that of the valve main body 51. The first valve pressing member 52 has a closing part 52b. The closing part 52b closes the central hole 51a formed in the valve body 51 when the check valve 50 prevents the refrigerant flow. One or more peripheral holes 52 a are formed around the closing portion 52 b of the first valve pressing member 52. In the present embodiment, a plurality of peripheral holes 52a are formed. The peripheral hole 52 a faces the peripheral edge portion 51 b of the valve body 51. The first valve pressing member 52 restricts the movement of the valve body 51 toward the bypass hole 32b when the check valve 50 prevents the refrigerant flow from the bypass pipe 110 to the bypass hole 32b.

(1-3-3) Second valve pressing member The second valve pressing member 53 has a cylindrical shape as a whole. A circular passage hole 53 a is formed at the center of the second valve pressing member 53. The second valve pressing member 53 mainly has an annular regulating portion 53b that is disposed on the peripheral side of the passage hole 53a. The passage hole 53a is a hole through which the refrigerant passes. The diameter of the passage hole 53 a is larger than the diameter of the central hole 51 a and smaller than the outer diameter of the valve body 51. The second valve pressing member 53 regulates the movement of the valve body 51 toward the bypass pipe 110 when the check valve 50 does not block the flow of the refrigerant from the bypass hole 32b to the bypass pipe 110. The second valve pressing member 53 is disposed on the opposite side of the first valve pressing member 52 with the valve main body 51 interposed therebetween.

(1-3-4) Movement of Valve Body and Flow of Refrigerant When the pressure from the bypass hole 32b is higher than the pressure on the bypass pipe 110 side, the refrigerant flows from the bypass hole 32b to the bypass pipe 110. At this time, the refrigerant passes through the peripheral hole 52a and is supplied to the peripheral side of the area where the valve body 51 slides. Then, the refrigerant passing through the peripheral hole 52 a pushes the peripheral portion 51 b of the valve main body 51 facing the peripheral hole 52 a, thereby moving the valve main body 51 toward the second valve pressing member 53. When the valve main body 51 contacts the second valve pressing member 53, the movement of the valve main body 51 is regulated by the second valve pressing member 53.

  At this time, the valve body 51 is pressed against the second valve pressing member 53 by the refrigerant that has passed through the peripheral hole 52a. Then, the refrigerant that has passed through the peripheral hole 52a passes through the central hole 51a of the valve body 51 and the passage hole 53a of the second valve pressing member 53, and flows through the bypass pipe 110 to the discharge pipe 24 side.

  On the other hand, when the pressure from the bypass hole 32b changes from a higher state to a lower state than the pressure on the bypass pipe 110 side, the refrigerant flows from the bypass pipe 110 toward the bypass hole 32b and is pressed against the second valve pressing member 53. The valve body 51 that has been moved moves toward the first valve pressing member 52. And it will be in the state pressed against the 1st valve pressing member 52. In other words, when the refrigerant does not flow from the bypass hole 32b to the bypass pipe 110 side, the first valve pressing member 52 restricts the movement of the valve body 51 to the bypass hole 32b side.

  In this state, the central hole 51a is closed by the closing portion 52b of the first valve pressing member 52, whereby the refrigerant on the bypass pipe 110 side is restricted from flowing to the bypass hole 32b side. Further, the peripheral hole 52a is closed by a peripheral edge portion 51b of the valve body 51 facing the peripheral hole 52a. That is, when the check valve 50 checks the flow of the refrigerant, the peripheral hole 52a is closed by the peripheral edge portion 51b, so that the refrigerant flowing from the bypass pipe 110 passes through the peripheral hole 52a and passes through the bypass hole. The flow to the 32b side is restricted.

  When the pressure from the bypass hole 32 b changes from a lower state to a higher state than the pressure on the bypass pipe 110 side, the valve main body 51 pressed against the first valve pressing member 52 moves toward the second valve pressing member 53. And it will be in the state pressed against the 2nd valve pressing member 53 again.

(2) Operation of scroll compressor The refrigerant compression process is as described above. The refrigerant in the compression chamber Sc is gradually compressed as the volume of the compression chamber Sc decreases. In the present embodiment, when the refrigerant compression ratio is in the second range, the pressure from the bypass hole 32b is higher than the pressure on the bypass pipe 110 side. At this time, the check valve 140 opens a passage to the bypass channel. Therefore, the refrigerant in the middle of compression is guided to the bypass flow path.

  On the other hand, when the compression ratio of the refrigerant is within the first range, the pressure from the bypass hole 32b is equal to or lower than the pressure on the bypass pipe 110 side. At this time, the check valve 140 closes the passage to the bypass channel. Therefore, the refrigerant in the middle of compression is not led to the bypass channel. In this case, the refrigerant being compressed is further compressed in the compression chamber and then discharged from the discharge hole 32a to the refrigerant discharge space S3. The compressed refrigerant is discharged from the discharge pipe 24 after being guided to the motor housing space S2.

  As described above, when the compression ratio of the refrigerant is within the first range, that is, when the drive motor 70 is driven at a high load, the check valve 140 closes the passage to the bypass flow path, The compressed refrigerant is guided to the motor housing space S2. When the compression ratio of the refrigerant is within the second range, that is, when the drive motor 70 is driven at a low load, the check valve 140 opens the passage to the bypass flow path, thereby Bypass to bypass channel.

(3) Features of Scroll Compressor The scroll compressor 10 of this embodiment includes a check valve 140. Since the check valve 140 opens and closes due to the difference between the pressure from the bypass hole 32b and the pressure on the bypass pipe 110 side, it is possible to suppress a decrease in the efficiency of the drive motor 70 without electrical control.

<Third Embodiment>
FIG. 6A is a partial longitudinal sectional view of the scroll compressor 10 of the third embodiment. FIG. 6B is a plan view of the fixed scroll 30. Specifically, it is a plan view seen from the vertically upward direction. Here, differences from the scroll compressor 10 of the second embodiment will be mainly described. The same reference numerals are used for elements having the same structure and function as the scroll compressor 10 of the second embodiment.

(1) Configuration of Scroll Compressor (1-1) Fixed Scroll As described above, the fixed side end plate 32 of the fixed scroll 30 has the discharge hole 32a and the bypass hole 32b. In the present embodiment, the fixed-side end plate 32 is further formed with a plurality of relief holes 32c through which the refrigerant being compressed passes. In the present embodiment, three relief holes 32c are formed. Each relief hole 32 c communicates with the refrigerant discharge space S <b> 3 that communicates with the compression chamber of the scroll compression mechanism 60. The number of relief holes 32c may be one.

(1-2) Bypass piping As already described, the bypass piping 110 as an example of a bypass member forms a bypass flow path. One end of the bypass pipe 110 is connected to the discharge pipe 24. The other end of the bypass pipe 110 is connected to the bypass hole 32b. The other end of the bypass pipe 110 has a tapered portion so as to avoid contact with the relief valve 150 around the bypass hole 32b.

(1-3) Relief Valve In the present embodiment, three relief valves 150 are arranged on the fixed side end plate 32.
The three relief valves 150 are arranged at positions corresponding to the three relief holes 32c. Each relief valve 150 is attached so as to cover the corresponding relief hole 32c. Each relief valve 150 is a check valve that opens and closes due to the difference between the pressure from the corresponding relief hole 32c and the pressure in the refrigerant discharge space S3. More specifically, the flow of the refrigerant is not blocked when the pressure from the relief hole 32c is higher than the pressure in the refrigerant discharge space S3. That is, the passage to the refrigerant discharge space S3 is opened. On the other hand, when the pressure from the relief hole 32c is equal to or lower than the pressure in the refrigerant discharge space S3, the refrigerant flow is blocked. That is, the passage to the refrigerant discharge space S3 is closed.

(2) Features of Scroll Compressor The scroll compressor 10 of this embodiment includes a plurality of relief valves 150. Since the plurality of relief valves 150 are opened and closed by the difference between the pressure from the corresponding relief hole 32c and the pressure in the refrigerant discharge space S3, excessive compression by the scroll compression mechanism 60 can be prevented. That is, in the present embodiment, it is possible to achieve both suppression of a decrease in efficiency of the drive motor 70 and prevention of refrigerant overcompression.

<Fourth embodiment>
FIG. 7 is a partial longitudinal sectional view of the scroll compressor 10 of the fourth embodiment. Here, differences from the scroll compressor 10 of the first embodiment will be mainly described. The same reference numerals are used for elements having the same structure and function as the scroll compressor 10 of the first embodiment. In the present embodiment, the scroll compressor 10 includes a partition member 160. Moreover, the relief valve 170 as an example of an on-off valve is provided.

(1) Configuration of scroll compressor (1-1) Partition member The partition member 160 is arranged in the refrigerant discharge space S3. The partition member 160 divides the refrigerant discharge space S3 into a first space S11 and a second space S12. As will be described in detail later, the pressure in the second space S12 is lower than the pressure in the first space S11.

(1-2) Fixed Scroll As already described, the discharge hole 32 a is formed in the center of the fixed side end plate 32 of the fixed scroll 30. The discharge hole 32a is located in a portion included in the first space S11. The discharge hole 32a discharges the compressed refrigerant.

  In the present embodiment, a bypass hole 32 b is further formed on the left side from the center of the fixed side end plate 32. The bypass hole 32b is located in a portion included in the second space S12. The bypass hole 32 b is a hole that communicates with the compression chamber Sc of the scroll compression mechanism 60. The bypass hole 32b penetrates the fixed side end plate 32 in the thickness direction. The bypass hole 32b discharges the refrigerant being compressed.

(1-3) Bypass piping As already described, the bypass piping 110 as an example of a bypass member forms a bypass flow path. One end of the bypass pipe 110 is connected to the discharge pipe 24. The other end of the bypass pipe 110 is connected to the second space S12. The other end of the bypass pipe 110 is connected to the opening of the chamber cover 120.

(1-4) Relief Valve In this embodiment, the relief valve 170 is used instead of the solenoid valve 130 as an example of the on-off valve. The relief valve 170 is disposed on the fixed side end plate 32. The relief valve 170 is attached so as to cover the bypass hole 32b. The relief valve 170 is a check valve that opens and closes due to the difference between the pressure from the bypass hole 32b and the pressure in the second space S12. More specifically, the refrigerant flow is not blocked when the pressure from the bypass hole 32b is higher than the pressure in the second space S12. That is, the passage to the second space S12 is opened. In the present embodiment, when the compression ratio of the refrigerant is within the second range, the passage to the bypass channel is configured to be opened. In this case, the refrigerant flows from the bypass hole 32b to the bypass pipe 110 side.

  On the other hand, the flow of the refrigerant is blocked when the pressure from the bypass hole 32b is equal to or lower than the pressure in the second space S12. That is, the passage to the second space S12 is closed. In the present embodiment, when the compression ratio of the refrigerant is within the first range, the passage to the bypass flow path is closed. In this case, the refrigerant does not flow from the bypass hole 32b to the bypass pipe 110 side.

  The positions, sizes, and the like of the bypass hole 32b and the relief valve 170 are determined so as to realize the refrigerant flow as described above.

(2) Operation of scroll compressor The refrigerant compression process is as described above. The refrigerant in the compression chamber Sc is gradually compressed as the volume of the compression chamber Sc decreases. In the present embodiment, when the refrigerant compression ratio is in the second range, the pressure from the bypass hole 32b is higher than the pressure on the bypass pipe 110 side. At this time, the relief valve 170 opens the passage to the bypass channel. Therefore, the refrigerant in the middle of compression is guided to the second space S12 that leads to the bypass flow path.

  On the other hand, when the compression ratio of the refrigerant is within the first range, the pressure from the bypass hole 32b is equal to or lower than the pressure on the bypass pipe 110 side. At this time, the relief valve 170 closes the passage to the bypass flow path. Therefore, the refrigerant in the middle of compression is not led to the bypass channel. In this case, the refrigerant being compressed is further compressed in the compression chamber and then discharged from the discharge hole 32a to the first space S11 of the refrigerant discharge space S3. The compressed refrigerant is discharged from the discharge pipe 24 after being guided to the motor housing space S2.

  As described above, when the compression ratio of the refrigerant is within the first range, that is, when the drive motor 70 is driven at a high load, the relief valve 170 closes the passage to the bypass flow path to compress the refrigerant. The subsequent refrigerant is guided to the motor housing space S2. When the compression ratio of the refrigerant is within the second range, that is, when the drive motor 70 is driven at a low load, the relief valve 170 opens the passage to the bypass flow path, thereby bypassing the refrigerant being compressed. Bypass to the flow path.

(3) Features of Scroll Compressor The scroll compressor 10 of this embodiment includes a relief valve 170. Since the relief valve 170 opens and closes due to the difference between the pressure from the bypass hole 32b and the pressure on the bypass pipe 110 side, it is possible to suppress a reduction in the efficiency of the drive motor 70 without electrical control.

  Further, the scroll compressor 10 of the present embodiment includes a partition member 160. The partition member 160 divides the refrigerant discharge space S3 into a first space S11 and a second space S12. In the present embodiment, the refrigerant discharge space S3 is divided by the partition member 160, whereby the refrigerant that has passed through the relief valve 170 can be discharged outside without passing through the motor housing space S2. By providing the second space S12 in which the refrigerant being compressed is discharged in the refrigerant discharge space S3, it is possible to suppress a decrease in the efficiency of the drive motor 70.

<Modification>
In the above description, the bypass pipe 110 is taken as an example of the bypass member. However, the present invention is not limited to this configuration as long as the compressed refrigerant is bypassed to the discharge pipe 24 without passing through the motor housing space S2. For example, the bypass member may be formed so that the compressed refrigerant is guided to the end of the discharge pipe 24 through the inside of the casing 20.

  In the above description, the other end of the bypass pipe 110 is connected to the chamber cover 120, that is, the refrigerant in the middle of compression or after compression is bypassed from the refrigerant discharge space S3, but from the refrigerant discharge space S3 to the motor housing space. As long as the flow path reaches S2, the other end of the bypass pipe 110 may be connected to another portion. For example, the injection valve 26 may be connected to the side of the casing 20.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be made to the above embodiments. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 10 Scroll compressor 20 Casing 23 Intake pipe 24 Discharge pipe 32a Discharge hole 32b Bypass hole 32c Relief hole 60 Scroll compression mechanism 70 Drive motor 110 Bypass pipe 120 Chamber cover 130 Solenoid valve 140 Check valve 150 Relief valve 160 Partition member 170 Relief valve

JP 2000-97172 A

Claims (6)

A casing (20);
A suction pipe (23) connected to the casing for sucking refrigerant;
A compression mechanism (60) disposed within the casing for compressing the refrigerant;
A motor (70) disposed in the motor housing space in the casing and driving the compression mechanism;
A discharge pipe (24) connected to the casing for discharging the compressed refrigerant from the motor housing space;
A bypass member (110) that forms a bypass flow path for bypassing the refrigerant during or after compression to the discharge pipe without passing through the motor housing space;
When the compression ratio of the refrigerant is within the first range, the passage to the bypass flow path is closed, and when the compression ratio is within the second range where the compression ratio is smaller than the first range, An on-off valve (130, 140, 170) for opening a passage to the bypass flow path;
A compressor (10) comprising: The bypass member is a bypass pipe (110),
One end of the bypass member is connected to the discharge pipe, and the other end of the bypass member is connected to a flow path from the refrigerant discharge space leading to the compression chamber of the compression mechanism to the motor housing space,
The on-off valve is an electromagnetic valve or an electric valve attached to the bypass member.
The compressor according to claim 1. A chamber cover (120) having an opening and forming the refrigerant discharge space;
The other end of the bypass member is connected to the opening.
The compressor according to claim 2. The compression mechanism has a bypass hole (32b) through which the refrigerant being compressed passes.
The bypass member is a bypass pipe (110),
One end of the bypass member is connected to the discharge pipe, and the other end of the bypass member is connected to the bypass hole,
The on-off valve is a check valve attached to the bypass member, which opens and closes due to a difference between the pressure from the bypass hole and the pressure on the bypass pipe side.
The compressor according to claim 1. In addition to the bypass hole, the compression mechanism has a relief hole (32c) through which the refrigerant being compressed passes.
The relief hole communicates with a refrigerant discharge space that communicates with a compression chamber of the compression mechanism,
A relief valve (150), which is a check valve attached to cover the relief hole and which opens and closes due to a difference between the pressure from the relief hole and the pressure of the refrigerant discharge space;
The compressor according to claim 4. A chamber cover (120) that forms a refrigerant discharge space leading to a compression chamber of the compression mechanism;
A partition member (160) for dividing the refrigerant discharge space into a first space and a second space having a lower pressure than the first space;
Further comprising
A portion of the compression mechanism included in the first space has a discharge hole (32a) for discharging the compressed refrigerant.
A bypass hole (32b) for discharging the refrigerant being compressed is formed in a portion of the compression mechanism included in the second space,
The bypass member is a bypass pipe (110),
One end of the bypass member is connected to the discharge pipe, and the other end of the bypass member is connected to the second space,
The on-off valve is a relief valve attached so as to cover the bypass hole, which opens and closes due to a difference between the pressure from the bypass hole and the pressure in the second space.
The compressor according to claim 1.

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