Hermetic electric compressor

Abstract

Provided is a hermetic electric compressor, wherein: a discharge port 66a is disposed further downstream of a vortex flow than a joint 66b; a bent portion 66c is formed between the joint 66b and the discharge port 66a; a virtual vertical line 66aY of an opening face formed in the discharge port 66a is set as the circumferential direction of a sealed container 10; and a fluid with a low amount of lubricating oil is extracted from a discharge port 66 by utilizing a vortex flow of a mixed fluid comprising a refrigerant and the lubricating oil in a gap space between a compression mechanism 20 and an electric motor 30. Due to this configuration, the amount of oil discharged from the sealed container 10 can be reduced.

Description

[Technical Field]

[0001] The present invention relates to a hermetic electric compressor used in an outdoor unit of an air conditioner or a refrigerator. [Background technology]

[0002] Patent Document 1 describes a hermetic electric compressor that has a compression mechanism and an electric motor inside a sealed container, and a discharge pipe is arranged in the space between the compression mechanism and the electric motor, and the problem is to reduce the amount of lubricating oil discharged from this discharge pipe to the outside of the sealed container. In Patent Document 1, the amount of oil discharged from the sealed container is reduced by causing the refrigerant to collide with recesses provided on the outer surface of the coil end of the electric motor, thereby separating the lubricating oil from the refrigerant. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-218214 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, the discharge port of the discharge pipe is attached radially to the sealed container, so if the lubricating oil is not sufficiently separated from the refrigerant by colliding with a recess provided on the outer surface of the motor coil end, the lubricating oil will be discharged from the discharge pipe together with the refrigerant.

[0005] Therefore, an object of the present invention is to provide a hermetic electric compressor that can reduce the amount of oil discharged from the hermetic container by utilizing the vortex flow of the mixed fluid of refrigerant and lubricating oil in the gap space between the compression mechanism section and the electric motor section to extract a fluid with a low lubricating oil content from the discharge port. [Means for solving the problem]

[0006] The hermetic type electric compressor of the present invention as set forth in claim 1 includes a compression mechanism section 20 and an electric motor section 30 in a sealed container 10, the compression mechanism section 20 and the electric motor section 30 being connected by a drive shaft 40, the compression mechanism section 20 being disposed on one side of the sealed container 10, and the electric motor section 30 being disposed on the other side of the sealed container 10, and the electric motor section 30 being composed of an annular stator 31 and a rotor 32 configured to be rotatable inside the stator 31. a discharge pipe 66 disposed in a gap space 71a between the compression mechanism section 20 and the electric motor section 30, a discharge port 66a of the discharge pipe 66 extending from a joint 66b with the sealed container 10 into the gap space 71a, the drive shaft 40 being journalled by a bearing section 51, an oil reservoir section 17 being formed in an inner bottom section 16 of the sealed container 10, and the drive shaft 40 being supplied with lubricating oil stored in the oil reservoir section 17 to the compression mechanism section 20 and the an oil supply passage leading to bearings is formed; a balancer is provided on the drive shaft; the balancer is located below the compression mechanism and above the electric motor; an oil receiver is provided on the outer periphery of the balancer to receive the lubricating oil dropping toward the electric motor; the balancer and the oil receiver are covered with a cover; the refrigerant compressed by the compression mechanism is discharged into the sealed container; the refrigerant discharged into the sealed container becomes a vortex flow in the gap space by rotation of the drive shaft and is discharged from the discharge pipe to the outside of the sealed container; the discharge port is located downstream of the vortex flow relative to the joint, and the discharge port is positioned vertically above the stator without reaching vertically above the rotor. and near the center of the radial width of the stator 31 The discharge port 66a is disposed at the same height as the cover 110. A hermetic type electric compressor according to a second aspect of the present invention is the hermetic type electric compressor according to the first aspect, characterized in that a bent portion 66c is formed between the joint portion 66b and the discharge port 66a. A hermetic electric compressor according to a third aspect of the present invention is the hermetic electric compressor according to the second aspect, characterized in that the discharge pipe 66 is joined vertically to the hermetic casing 10 at the joint 66b. The hermetic electric compressor of the present invention as set forth in claim 4 is the hermetic electric compressor as set forth in claim 1, characterized in that at the joint 66b, the discharge pipe 66 is joined at an incline with respect to the hermetic container 10. A hermetic type electric compressor according to a fifth aspect of the present invention is the hermetic type electric compressor according to the fourth aspect, characterized in that the section from the joint portion 66b to the discharge port 66a is a straight pipe. The hermetic electric compressor of the present invention described in claim 6 is characterized in that, in the hermetic electric compressor described in any one of claims 1 to 5, a virtual vertical line 66aY of the opening surface formed in the discharge port 66a is set in the circumferential direction of the hermetic container 10. [Effects of the Invention]

[0007] According to the present invention, by positioning the discharge outlet of the discharge pipe downstream of the vortex flow from the joint and arranging the discharge outlet in a direction opposite to the vortex flow, it is possible to take out a fluid with a low lubricating oil content from the discharge outlet by utilizing the vortex flow of the mixed fluid of refrigerant and lubricating oil in the gap space between the compression mechanism section and the electric motor section, thereby reducing the amount of oil discharged from the sealed container. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a cross-sectional side view of a main portion of a hermetic electric compressor according to an embodiment of the present invention; [Figure 2] A plan cross-sectional view of the main part of the hermetic electric compressor [Figure 3] FIG. 10 is a cross-sectional side view of a main part of a hermetic electric compressor according to another embodiment of the present invention; [Figure 4] A plan cross-sectional view of the main part of the hermetic electric compressor DETAILED DESCRIPTION OF THE INVENTION

[0009] In the hermetic electric compressor according to the first embodiment of the present invention, the discharge port is disposed downstream of the vortex flow from the joint portion, and the discharge port is disposed vertically above the stator without extending vertically above the rotor. and closer to the center of the radial width of the statorThe refrigerant compressed by the compression mechanism and discharged into the sealed container contains lubricating oil, and the lubricating oil and the refrigerant form a vortex flow in the gap between the compression mechanism and the electric motor. According to this embodiment, the discharge port of the discharge pipe is located downstream of the vortex flow from the joint and is oriented in the direction opposite to the vortex flow, so that the vortex flow of the refrigerant and lubricating oil mixture in the gap between the compression mechanism and the electric motor can be utilized to extract a fluid with less lubricating oil from the discharge port, thereby reducing the amount of oil discharged from the sealed container.

[0010] In a second embodiment of the present invention, a bent portion is formed between the joint portion and the discharge port in the hermetic electric compressor according to the first embodiment. According to this embodiment, by forming the bent portion, the discharge port of the discharge pipe can be located downstream of the joint portion in the vortex flow, and the discharge port can be provided in a direction against the vortex flow.

[0011] In the third embodiment of the present invention, in the hermetic type electric compressor according to the second embodiment, the discharge pipe is joined vertically to the hermetic container at the joint portion. According to this embodiment, the discharge pipe can be easily joined to the hermetic container.

[0012] In a fourth embodiment of the present invention, in the hermetic electric compressor according to the first embodiment, the discharge pipe is joined at an incline with respect to the sealed container at the joint. According to this embodiment, by joining the discharge pipe at an incline with respect to the sealed container, the discharge port of the discharge pipe can be located downstream of the joint with respect to the vortex flow, and the discharge port can be provided in a direction against the vortex flow.

[0013] In the fifth embodiment of the present invention, the section from the joint to the discharge port in the hermetic type electric compressor of the fourth embodiment is a straight pipe. This embodiment eliminates the need for bending the discharge pipe, and makes it easier to insert the discharge pipe into the hermetic container.

[0014] In a sixth embodiment of the present invention, in the hermetic compressor according to any one of the first to fifth embodiments, a virtual vertical line of the opening plane formed at the discharge port is set to the circumferential direction of the sealed container. According to this embodiment, a fluid with a low lubricating oil content can be taken out from the discharge port by utilizing the vortex flow of the refrigerant and lubricating oil mixture in the gap space between the compression mechanism and the electric motor, thereby reducing the amount of oil discharged from the sealed container. [Example]

[0015] An embodiment of the present invention will now be described with reference to the drawings. Fig. 1 is a side cross-sectional view of a main part of a hermetic electric compressor according to this embodiment, and Fig. 2 is a plan cross-sectional view of a main part of the same hermetic electric compressor. In this embodiment, a hermetic scroll electric compressor installed vertically will be described.

[0016] The sealed container 10 is made up of a cylindrical body shell 11 having an axis in the vertical direction, a bowl-shaped lower shell 12 airtightly welded to the lower end of the body shell 11, and a bowl-shaped upper shell 13 airtightly welded to the upper end of the body shell 11. A terminal cover 14 (see FIG. 2) is provided on the outer periphery of the sealed container 10, and inside the terminal cover 14 is provided a power supply terminal 15 for supplying power to the electric motor section 30. An oil reservoir 17 is formed in the inner bottom 16 of the sealed container 10.

[0017] The sealed container 10 contains a compression mechanism section 20 and an electric motor section 30. The compression mechanism section 20 is disposed on one side of the sealed container 10, and the electric motor section 30 is disposed on the other side of the sealed container 10. The compression mechanism section 20 is disposed above the electric motor section 30. The compression mechanism section 20 and the electric motor section 30 are connected by a drive shaft 40.

[0018] The compression mechanism 20 is composed of a fixed scroll 21 and an orbiting scroll 22 . The fixed scroll 21 is composed of an end plate 21a and a spiral (involute) wrap 21b formed on the lower surface of the end plate 21a. The orbiting scroll 22 is composed of an end plate 22a and a spiral (involute) wrap 22b formed on the upper surface of the end plate 22a. A cylindrical boss 24 is provided at the center of the lower surface of the end plate 22a of the orbiting scroll 22. The wrap 21b of the fixed scroll 21 and the wrap 22b of the orbiting scroll 22 are meshed with each other, and a plurality of compression chambers 23 are formed between the fixed scroll 21 and the orbiting scroll 22 by both the wraps 21b, 22b. A discharge hole 25 is provided in the center of the end plate 21a of the fixed scroll 21, and a discharge valve 26 is provided in the discharge hole 25.

[0019] The electric motor unit 30 is composed of an annular stator 31 and a rotor 32 that is rotatably arranged inside the stator 31. The stator 31 is fixed to the inner peripheral surface of the sealed container 10. The rotor 32 is fixed to a drive shaft 40.

[0020] An eccentric shaft portion 41 is formed at the upper end of the drive shaft 40. The axial center of the eccentric shaft portion 41 is eccentric with respect to the axial center of the drive shaft 40. A positive displacement oil pump 43 is provided at the lower end of the drive shaft 40. An oil supply passage 42 is formed within the drive shaft 40, which guides the lubricating oil stored in the oil reservoir 17 to the compression mechanism 20 and the bearings (main bearing 51, sub-bearing 80). An oil return pipe 44 is connected to the boss accommodating portion 52, and the lubricating oil guided from the compression mechanism 20 to the boss accommodating portion 52 is guided to the lower part of the sealed container 10 by the oil return pipe 44.

[0021] A main frame 50 is provided at the upper interior portion of the sealed container 10. The compression mechanism 20 is disposed on top of the main frame 50. The main frame 50 has a main bearing (bearing portion) 51 and a boss accommodating portion 52 formed in the center thereof, and is fixed to the inner peripheral surface of the sealed container 10. The main bearing 51 is formed in a cylindrical shape protruding downward from the center of the lower surface of the main frame 50, and supports the upper end of the drive shaft 40. The boss accommodating portion 52 is formed as a cavity downward from the center of the upper surface of the main frame 50, and accommodates the boss 24 of the orbiting scroll 22. The eccentric shaft portion 41 is inserted into the boss 24 via an orbiting bearing 61.

[0022] The orbiting scroll 22 is disposed between the fixed scroll 21 and the main frame 50. The fixed scroll 21 is fastened to the upper surface of the main frame 50 with screws 63. An Oldham ring 62 is disposed between the orbiting scroll 22 and the main frame 50, and the Oldham ring 62 restrains the rotation of the orbiting scroll 22 on its axis.

[0023] The interior of the sealed container 10 is divided into a high-pressure space 71 formed below the main frame 50 and a discharge space 72 formed above the main frame 50. The high-pressure space 71 consists of a gap space 71a formed between the main frame 50 and the electric motor unit 30, and a lower high-pressure space 71b formed between the electric motor unit 30 and the inner bottom 16 of the sealed container 10. The discharge space 72 and the gap space 71 a communicate with each other through the vertical groove 64 , and the gap space 71 a and the lower high pressure space 71 b communicate with each other through a communication hole formed in the stator 31 and a gap between the stator 31 and the rotor 32 .

[0024] A suction pipe 65 that introduces low-pressure refrigerant to the compression chamber 23 is connected to the upper shell 13 of the sealed container 10. A discharge pipe 66 that discharges high-pressure refrigerant from the sealed container 10 to the outside of the sealed container 10 is connected to the body shell 11 of the sealed container 10. A discharge port 66a of the discharge pipe 66 is disposed in the void space 71a.

[0025] Below the electric motor unit 30, there is provided an auxiliary bearing (bearing unit) 80 that supports the lower end of the drive shaft 40. The auxiliary bearing 80 has a cylindrical boss unit 81 into which the drive shaft 40 is inserted, and an arm unit 82 that extends outward from the boss unit 81 and is fixed to the inner peripheral surface of the sealed container 10.

[0026] A balancer 90 is provided on the drive shaft 40. The balancer 90 is located below the compression mechanism 20 and above the electric motor 30. An oil receiver 100 is provided on the outer periphery of the balancer 90 to receive the lubricating oil that falls toward the electric motor section 30. A cover 110 that covers the balancer 90 is provided on the lower surface of the main frame 50.

[0027] The lubricating oil in the oil reservoir 17 is pumped up to the oil supply passage 42 by the positive displacement oil pump 43. The lubricating oil pumped up to the oil supply passage 42 is supplied to the main bearing 51 through the horizontal hole 42a, and is also supplied into the boss 24 through the upper end opening 42b of the drive shaft 40. The lubricating oil supplied into the boss 24 is supplied to the sliding surfaces of the compression mechanism 20, the Oldham ring 62, and the like. The lubricating oil supplied to the compression mechanism 20 and the main bearing 51 flows into the boss accommodating portion 52, and the lubricating oil that has flowed into the boss accommodating portion 52 is returned to the oil reservoir 17 through the oil return pipe 44.

[0028] The discharge pipe 66 has a discharge port 66a extending from a joint 66b with the sealed container 10 into the void space 71a. As shown in FIG. 2, the discharge pipe 66 has a bent portion 66c formed between the joint portion 66b and the discharge port 66a, so that the discharge port 66a is located downstream of the joint portion 66b in the vortex flow. The discharge pipe 66 is joined vertically to the sealed container 10. That is, a joint 66b of the discharge pipe 66 is joined so as to coincide with the radial direction of the sealed container 10. Furthermore, the discharge pipe 66 has an imaginary vertical line 66aY of the opening surface formed at the discharge port 66a aligned with the circumferential direction of the sealed container 10. That is, the imaginary vertical line 66aY is aligned with the vortex flow. In the figure, arrow R indicates the direction of rotation of drive shaft 40, and the rotation of drive shaft 40 causes a vortex flow of the mixed fluid of refrigerant and lubricating oil in gap space 71a.

[0029] The operation of the hermetic type electric compressor will be described below. When the electric motor unit 30 is driven, the rotor 32 rotates, thereby rotating the drive shaft 40. The rotation of the drive shaft 40 causes the orbiting scroll 22 to revolve relative to the fixed scroll 21. As the orbiting scroll 22 revolves, low-pressure refrigerant is drawn from the suction pipe 65 into the compression chambers 23 located on the periphery. The low-pressure refrigerant drawn into the compression chambers 23 is compressed by a change in the volume of the compression chambers 23. The compressed, high-pressure refrigerant is guided from the compression chambers 23 located in the center to the discharge hole 25, and is discharged into the discharge space 72 by opening the discharge valve 26. The high-pressure refrigerant discharged into the discharge space 72 passes through the fixed scroll 21 and the vertical grooves 64 formed in the main frame 50, and flows out into the high-pressure space 71 below the main frame 50. The high-pressure refrigerant that has reached the void space 71a becomes a vortex flow due to the rotation of the drive shaft 40, and is discharged out of the sealed container 10 through the discharge pipe 66.

[0030] The refrigerant compressed by the compression mechanism unit 20 and discharged into the sealed container 10 contains lubricating oil, and the lubricating oil and the refrigerant form a vortex flow in the gap space 71a between the compression mechanism unit 20 and the electric motor unit 30. According to this embodiment, the discharge port 66a of the discharge pipe 66 is positioned downstream of the vortex flow from the joint 66b, and the discharge port is provided in the direction opposite to the vortex flow, so that a fluid with less lubricating oil can be extracted from the discharge port 66a to the discharge pipe 66, thereby reducing the amount of oil discharged from the sealed container 10. Furthermore, according to this embodiment, by forming a bent portion 66c in the discharge pipe 66, the discharge outlet 66a of the discharge pipe 66 can be positioned downstream of the vortex flow from the joint portion 66b, and the discharge outlet can be provided in a direction opposite to the vortex flow. Furthermore, according to this embodiment, the discharge pipe 66 is joined vertically to the sealed container 10, so that joining of the discharge pipe 66 to the sealed container 10 can be easily carried out. Furthermore, according to this embodiment, by arranging the imaginary vertical line 66aY of the opening surface formed in the discharge port 66a in the circumferential direction of the sealed container 10, a fluid with a low lubricating oil content can be extracted from the discharge port 66a to the discharge pipe 66, thereby reducing the amount of oil discharged from the sealed container 10.

[0031] Fig. 3 is a side cross-sectional view of a main part of a hermetic electric compressor according to another embodiment of the present invention, and Fig. 4 is a plan cross-sectional view of a main part of the same hermetic electric compressor. Only the differences from Fig. 1 and Fig. 2 will be explained below, and the same functional members will be assigned the same reference numerals and explanations will be omitted.

[0032] The discharge pipe 66 according to this embodiment is a straight pipe from the joint 66b to the discharge port 66a, and the discharge port 66a extends into the void space 71a. As shown in FIG. 4, the discharge pipe 66 is joined at an angle to the sealed container 10 at the joint 66b, so that the discharge port 66a is positioned downstream of the vortex flow from the joint 66b, and the discharge port is provided in a direction opposite to the vortex flow. The discharge pipe 66 has an imaginary vertical line 66aY of the opening surface formed at the discharge port 66a in the circumferential direction of the sealed container 10, that is, the imaginary vertical line 66aY is in the direction along the vortex flow. In the figure, arrow R indicates the direction of rotation of drive shaft 40, and the rotation of drive shaft 40 causes a vortex flow of the mixed fluid of refrigerant and lubricating oil in gap space 71a.

[0033] According to this embodiment, the discharge port 66a of the discharge pipe 66 is positioned downstream of the vortex flow from the joint 66b, and the discharge port is provided in the direction opposite to the vortex flow, so that a fluid with less lubricating oil can be extracted from the discharge port 66a to the discharge pipe 66, thereby reducing the amount of oil discharged from the sealed container 10. Furthermore, according to this embodiment, by joining the discharge pipe 66 at an angle to the sealed container 10 at the joint 66b, the discharge outlet 66a of the discharge pipe 66 can be positioned downstream of the vortex flow from the joint 66b, and the discharge outlet can be provided in a direction opposite to the vortex flow. Furthermore, according to this embodiment, the section from the joint 66b to the discharge port 66a is a straight pipe, so that bending of the discharge pipe 66 is not necessary, and the operation of inserting the discharge pipe 66 into the sealed container 10 becomes easy. Furthermore, according to this embodiment, by aligning the imaginary vertical line 66aY of the opening surface formed at the discharge port 66a in the circumferential direction of the sealed container 10, oil can be extracted from the discharge port 66a to the discharge pipe 66, thereby reducing the amount of oil discharged from the sealed container 10. [Industrial Applicability]

[0034] The present invention can also be applied to horizontally installed hermetic scroll compressors, hermetic rotary compressors, and the like. [Explanation of symbols]

[0035] 10. Airtight containers 11. Torso shell 12 Lower shell 13 Upper shell 14 Terminal cover 15 Power supply terminal 16 Inner bottom 17 Oil sump 20 Compression mechanism 21 Fixed Scroll 21a Headboard 21b Rap 22 Swivel Scroll 22a Headboard 22b Rap 23 Compression chamber 24 Boss 25 Discharge hole 26 Discharge valve 30 Electric motor section 31 Stator 32 rotor 40 Drive shaft 41 Eccentric shaft part 42 Fuel Line 42a Horizontal cave 42b Top opening 43 Positive displacement oil pump 44 Oil return pipe 50 Mainframe 51 Main bearing (bearing part) 52 Boss storage area 61 Slewing bearing 62 Oldham Ring 63 Screw 64 Vertical grooves 65 Suction pipe 66 Discharge pipe 66a Discharge port 66aY Virtual vertical line 66b Joint 66c Bending section 71 High-Pressure Space 71a Void space 71b Lower high pressure space 72 Discharge space 80 Sub-bearing (bearing part) 81 Boss section 82 Arm section 90 Balancer 100 Oil pan 110 Cover R arrow

Claims

1. A compression mechanism and an electric motor are provided in a sealed container, The compression mechanism and the electric motor are connected by a drive shaft, The compression mechanism is disposed on one side of the sealed container, the electric motor unit is disposed in the other of the sealed containers, the electric motor unit is composed of an annular stator and a rotor configured to be rotatable inside the stator, and a discharge pipe is disposed in a gap space between the compression mechanism unit and the electric motor unit; The discharge pipe has a discharge port extending from a joint with the sealed container into the gap space, The drive shaft is supported by a bearing portion, An oil reservoir is formed at the inner bottom of the sealed container, an oil supply passage for guiding the lubricating oil stored in the oil reservoir to the compression mechanism and the bearing is formed in the drive shaft; A balancer is provided on the drive shaft, the balancer is located below the compression mechanism and above the electric motor; an oil receiver provided on the outer periphery of the balancer for receiving the lubricating oil dropping toward the electric motor; The balancer and the oil receiver are covered with a cover, The refrigerant compressed by the compression mechanism is discharged into the sealed container, The refrigerant discharged into the sealed container becomes a vortex flow in the gap space due to the rotation of the drive shaft, and is discharged out of the sealed container from the discharge pipe. A hermetic electric compressor, The discharge port is disposed downstream of the vortex flow from the joint portion, the discharge port is disposed at a position vertically above the stator and near the center of the radial width of the stator, without extending vertically above the rotor; The discharge port is disposed at the same height as the cover. A hermetic electric compressor characterized by:

2. A bent portion is formed between the joint portion and the discharge port.

2. The hermetic electric compressor according to claim 1.

3. At the joint, the discharge pipe is joined vertically to the sealed container.

3. The hermetic electric compressor according to claim 2.

4. At the joint, the discharge pipe is joined at an angle to the sealed container.

2. The hermetic electric compressor according to claim 1.

5. The pipe is straight from the joint to the discharge port.

5. The hermetic electric compressor according to claim 4.

6. A virtual vertical line of the opening surface formed at the discharge port is set to the circumferential direction of the sealed container.

6. The hermetic electric compressor according to claim 1, wherein the first and second coils are arranged in a parallel axial direction.

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