Scroll compressor

Abstract

To provide a highly efficient scroll compressor that can control force to press a revolving scroll to a stationary scroll.SOLUTION: A scroll compressor is provided with: a pressure introduction groove 55 at a thrust surface of a stationary scroll 11; and a communication groove 56a at a lap surface of a revolving scroll end plate 12a, where mutual grooves overlap at a certain crank angle and are communicated to another space to adjust internal pressure of the grooves, thereby optimizing back pressure applied to a revolving scroll 12. Accordingly, the scroll compressor can reduce unnecessary mechanical loss and has high efficiency.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a scroll compressor, particularly used in refrigerators such as air conditioners, water heaters, and refrigerators.

Background Art

[0002] Patent Document 1 discloses a scroll compressor used in air conditioners and the like. This scroll compressor provides a back pressure region on the anti-wrap surface of the orbiting scroll plate, and reduces leakage loss by pressing the orbiting scroll against the fixed scroll, improving the theoretical efficiency and heating / cooling capacity. That is, on the fixed scroll side that slides against the wrap surface of the orbiting scroll plate, grooves or spaces that always maintain the suction pressure are provided, and the differential pressure with the back pressure is utilized to press the orbiting scroll against the fixed scroll to make the behavior more stable.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a scroll compressor that further improves efficiency by enabling control of the force pressing the orbiting scroll against the fixed scroll.

Means for Solving the Problems

[0005] The scroll compressor of the present disclosure is configured such that a first compression chamber is formed on the outer wall side of the orbiting scroll wrap, a second compression chamber is formed on the inner wall side of the orbiting scroll wrap, and a back pressure region is formed on the anti-wrap surface of the orbiting scroll plate to press the orbiting scroll against the fixed scroll. In this scroll compressor, a pressure introduction groove is provided on the sliding surface of the fixed scroll, and a communication groove is provided on the wrap surface of the orbiting scroll wrap, and the grooves communicate with each other at a certain crank angle.

Effect of the Invention

[0006] The scroll compressor of the present disclosure can adjust the force pressing the orbiting scroll against the fixed scroll according to the strength of the pushing-back force of the orbiting scroll, reduce useless mechanical losses, and become a highly efficient scroll compressor.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3A

Figure 3B

Figure 3C

Figure 3D

Figure 4

Figure 5A

Figure 5B

Figure 5C

Figure 5D

[0008] (Knowledge etc. on which the present disclosure is based) When the inventors arrived at the present disclosure, the scroll compressor utilized the differential pressure with the back pressure and pressed the orbiting scroll against the fixed scroll so that its behavior became more stable. However, since the pressure in the compression chamber acting in the direction of pulling the orbiting scroll away from the fixed scroll fluctuates during one rotation of the crankshaft, the inventors discovered that there is a problem that, depending on a certain crank angle, it is pressed too hard more than necessary, and in order to solve this, the inventors arrived at constituting the subject matter of the present disclosure.

[0009] Therefore, the present disclosure provides a scroll compressor with improved efficiency by varying the back pressure applied to the mirror plate according to the strength of the force acting in the direction of pulling the orbiting scroll away from the fixed scroll.

[0010] Hereinafter, embodiments will be described in detail with reference to the drawings. However, a more detailed description may be omitted as necessary. For example, a detailed description of well-known matters or a redundant description of substantially the same configuration may be omitted. This is to avoid making the following description overly redundant and to facilitate understanding by those skilled in the art.

[0011] Note that the accompanying drawings and the following description are provided for those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims thereby.

[0012] (Embodiment 1) Hereinafter, Embodiment 1 will be described with reference to FIGS. 1 to 5D.

[0013] [1-1. Configuration] In FIGS. 1 to 5D, the scroll compressor is configured by arranging a compression mechanism portion 10 for compressing a refrigerant and an electric mechanism portion 20 for driving the compression mechanism portion 10 inside a hermetic container 1.

[0014] The hermetic container 1 is composed of a cylindrical body portion 1a extending along the vertical direction, a lower lid 1b closing the lower opening of the body portion 1a, and an upper lid 1c closing the upper opening of the body portion 1a. The hermetic container 1 is provided with a refrigerant suction pipe 2 for introducing the refrigerant into the compression mechanism portion 10 and a refrigerant discharge pipe 3 for discharging the refrigerant compressed by the compression mechanism portion 10 to the outside of the hermetic container 1.

[0015] The compression mechanism portion 10 has a fixed scroll 11, a turning scroll 12, and a rotating shaft 13 for turning and driving the turning scroll 12.

[0016] The electric mechanism portion 20 includes a stator 21 fixed to the hermetic container 1 and a rotor 22 disposed inside the stator 21. The rotating shaft 13 is fixed to the rotor 22, and an eccentric shaft 13a eccentric with respect to the rotating shaft 13 is formed at the upper end of the rotating shaft 13. An oil reservoir is formed in the eccentric shaft 13a by a recess opening on the upper surface of the eccentric shaft 13a.

[0017] Below the fixed scroll 11 and the turning scroll 12, a main bearing 30 for supporting the fixed scroll 11 and the turning scroll 12 is provided.

[0018] The main bearing 30 is formed with a bearing portion 31 for pivotally supporting the rotating shaft 13 and a boss accommodating portion 32. The main bearing 30 is fixed to the hermetic container 1 by welding or shrink fitting.

[0019] The fixed scroll 11 includes a disk-shaped fixed scroll mirror plate 11a, a spiral fixed scroll wrap 11b erected on the fixed scroll mirror plate 11a, and an outer peripheral wall portion 11c erected so as to surround the periphery of the fixed scroll wrap 11b. A discharge port 14 is formed at a substantially central portion of the fixed scroll mirror plate 11a.

[0020] The turning scroll 12 includes a disk-shaped turning scroll mirror plate 12a, a turning scroll wrap 12b erected on the wrap side end face of the turning scroll mirror plate 12a, and a cylindrical boss portion 12c formed on the non-wrap side end face of the turning scroll mirror plate 12a.

[0021] The fixed scroll wrap 11b of the fixed scroll 11 and the turning scroll wrap 12b of the turning scroll 12 are meshed with each other, and a plurality of compression chambers 15 are formed between the fixed scroll wrap 11b and the turning scroll wrap 12b.

[0022] The boss portion 12c is formed at a substantially center of the turning scroll mirror plate 12a and is housed in a boss housing portion 32 in a state of being inserted into the eccentric shaft 13a.

[0023] The fixed scroll 11 is fixed to the main bearing 30 by using a plurality of bolts (not shown) with the outer peripheral wall portion 11c. On the other hand, the turning scroll 12 is restricted in movement with respect to the fixed scroll 11 via a rotation restraint member 17 such as an oldham ring. The The rotation restraint member 17 that restrains the rotation of the turning scroll 12 is provided between the fixed scroll 11 and the main bearing 30. Thereby, as the eccentric shaft 13a of the rotary shaft 13 performs crank rotation, the turning scroll 12 performs a turning motion without rotating with respect to the fixed scroll 11.

[0024] An oil storage portion 4 for storing lubricating oil is formed at the bottom of the sealed container 1, and the lower end portion 13b of the rotary shaft 13 is pivotally supported by a sub-bearing 18 disposed at the lower portion of the sealed container 1.

[0025] A positive-displacement oil pump 5 is provided at the lower end of the rotating shaft 13. The oil pump 5 is arranged such that its suction port is located within the oil storage section 4. The oil pump 5 is driven by the rotating shaft 13 and reliably sucks up the lubricating oil in the oil storage section 4 provided at the bottom of the sealed container 1 regardless of the pressure conditions and operating speed, thus eliminating the concern of oil starvation.

[0026] A rotating shaft oil supply hole 13c is formed in the rotating shaft 13, extending from the lower end portion 13b of the rotating shaft 13 to the eccentric shaft 13a. The lubricating oil sucked up by the oil pump 5 is supplied into the bearing of the sub-bearing 18, the bearing portion 31, and the boss portion 12c through the rotating shaft oil supply hole 13c formed within the rotating shaft 13.

[0027] The refrigerant sucked in from the refrigerant suction pipe 2 is guided from the suction port 15a into the compression chamber 15. The compression chamber 15 moves while reducing its volume from the outer peripheral side towards the central portion, and the refrigerant that reaches a predetermined pressure in the compression chamber 15 is discharged from the discharge port 14 provided at the central portion of the fixed scroll 11 into the discharge chamber 6. A discharge reed valve (not shown) is provided at the discharge port 14. The refrigerant that reaches a predetermined pressure in the compression chamber 15 pushes open the discharge reed valve and is discharged into the discharge chamber 6. The refrigerant discharged into the discharge chamber 6 is led to the upper part inside the sealed container 1 and discharged from the refrigerant discharge pipe 3.

[0028] As shown in the enlarged cross-sectional view of the main part in Fig. 2, in the scroll compressor according to the present embodiment, the boss housing portion 32 is set as the high-pressure region A, and the outer peripheral portion of the orbiting scroll 12 where the rotation restraint member 17 is arranged is set as the intermediate-pressure region B, and the orbiting scroll 12 is pressed against the fixed scroll 11. Hereinafter, the configuration will be described.

[0029] The eccentric shaft 13a is inserted into the boss portion 12c through the swivel bearing 13d so as to be swivelly drivable. An oil groove 13e is formed on the outer peripheral surface of the eccentric shaft 13a.

[0030] A ring-shaped seal member 33 is provided on the thrust surface of the main bearing 30 that receives the thrust force of the swivel scroll plate 12a. The seal member 33 is disposed on the outer periphery of the boss housing portion 32.

[0031] The inside of the sealed container 1 is filled with a refrigerant at the same high pressure as the refrigerant discharged into the discharge chamber 6. Since the rotary shaft oil supply hole 13c opens at the upper end of the eccentric shaft 13a, the inside of the boss portion 12c becomes a high-pressure region A equivalent to the discharged refrigerant.

[0032] The lubricating oil introduced into the boss portion 12c through the rotary shaft oil supply hole 13c is supplied to the swivel bearing 13d and the boss housing portion 32 by the oil groove 13e formed on the outer peripheral surface of the eccentric shaft 13a. Since the seal member 33 is provided on the outer periphery of the boss housing portion 32, the boss housing portion 32 becomes the high-pressure region A.

[0033] The swivel scroll plate 12a is formed with a first oil introduction hole 51 that opens toward the inside of the boss portion 12c, a first oil discharge hole 52 that opens on the outer periphery of the lapped side end face, and a first plate oil communication path 53 that connects the first oil introduction hole 51 and the first oil discharge hole 52. The swivel scroll plate 12a is provided with a first oil introduction hole 51 that opens toward the inside of the boss portion 12c, a first oil discharge hole 52 that opens on the outer periphery of the lapped side end face, and a first plate oil communication path 53 that connects the first oil introduction hole 51 and the first oil discharge hole 52.

[0034] The swivel scroll plate 12a is also provided with a second oil introduction hole 61 that opens in the intermediate pressure region B of the outer peripheral portion of the swivel scroll 12, a second oil discharge hole 62 that opens in the compression chamber 15, and a second plate oil communication path 63 that connects the second oil introduction hole 61 and the second oil discharge hole 62. The second oil introduction hole 61 is formed on the upper surface of the swivel scroll plate 12a.

[0035] In this way, by forming the second oil outlet hole 62 in the orbiting scroll 12 to intermittently communicate the intermediate pressure region B with the compression chamber 15, the intermediate pressure in the compression chamber 15 is guided to the intermediate pressure region B, and the orbiting scroll 12 can be pressed against the fixed scroll 11 with the minimum necessary load under various operating conditions. Therefore, while reducing the frictional loss of the compressor, it is possible to prevent the orbiting scroll 12 from separating from the fixed scroll 11, and the airtightness of the compression chamber 15 can be enhanced.

[0036] FIG. 3 is a diagram showing the volume change of the compression chamber accompanying the orbiting motion of the scroll compressor, and shows a state where the orbiting scroll 12 is meshed with the fixed scroll 11 and viewed from the back of the orbiting scroll 12. FIG. 3B shows a state where the rotation has advanced 90 degrees from FIG. 3A, FIG. 3C shows a state where the rotation has further advanced 90 degrees from FIG. 3B, and FIG. 3D shows a state where the rotation has further advanced 90 degrees from FIG. 3C.

[0037] As the compression chamber 15 formed by the fixed scroll 11 and the orbiting scroll 12, a first compression chamber 15A is formed on the outer wall side of the orbiting spiral wrap 12b, and a second compression chamber 15B is formed on the inner wall side of the orbiting spiral wrap 12b.

[0038] Then, in a state where the fixed scroll 11 and the orbiting scroll 12 are meshed, by extending the outer peripheral end portion 11be of the fixed spiral wrap 11b to be equivalent to the outer peripheral end portion 12be of the orbiting spiral wrap 12b, the position for confining the refrigerant in the first compression chamber 15A and the position for confining the refrigerant in the second compression chamber 15B are shifted by approximately 180 degrees. Furthermore, the suction volume of the first compression chamber 15A is configured to be larger than the suction volume of the second compression chamber 15B.

[0039] Furthermore, in the scroll compressor of the present embodiment, as shown in the view of the meshing surface of the fixed scroll 11 and the orbiting scroll 12 in FIG. 4, two pressure introduction grooves 55 are provided on the thrust surface 54a of the fixed scroll 11, and two communication grooves 56a communicating with the suction space and one hole 56b communicating with the space in the intermediate pressure region B as required are provided on the thrust surface 54b of the orbiting scroll. They are configured to communicate with each other's grooves, the compression chamber 15, or the suction port 15a, or the space in the intermediate pressure region B at a certain crank angle.

[0040] Then, the pressure introduction groove 55 provided in the fixed scroll 11 is always set within the range where the orbiting scroll mirror plate 12a moves, and it cannot communicate with other spaces except through the communication groove 56a. That is, the pressure introduction groove 55 is configured not to be directly connected to the compression chamber 15. Incidentally, the pressure introduction groove 55 and the communication groove 56a are configured to communicate with the compression chamber 15 at a timing when they reach the suction pressure.

[0041] [1-2. Operation] Regarding the scroll compressor configured as described above, its operation and function will be described below.

[0042] As shown in FIGS. 5A to 5D, the scroll compressor with the above configuration can control the inside of the pressure introduction groove 55 to reach a predetermined pressure for each crank angle by performing communication and disconnection between the pressure introduction groove 55 provided on the thrust surface 54a of the fixed scroll 11 and the communication groove 56a communicating with the suction space provided on the thrust surface 54b of the orbiting scroll. For example, in FIG. 5A, both the two pressure introduction grooves 55 and the two communication grooves 56a are in communication; in FIG. 5B, only one side of the two pressure introduction grooves 55 and the two communication grooves 56a is in communication. Also, in FIG. 5C, both the two pressure introduction grooves 55 and the two communication grooves 56a are not in communication, and one of the pressure introduction grooves 55 communicates with the hole 56b; in FIG. 5D, only one side of the two pressure introduction grooves 55 and the two communication grooves 56a is in communication.

[0043] Therefore, when the pressing force of the orbiting scroll 12 becomes weak at a certain crank angle, by communicating the pressure introduction groove 55 with a space at a pressure lower than the intermediate pressure region B, an auxiliary role for the pressing force can be performed, and tipping can be suppressed.

[0044] Conversely, when the pressing force with which the orbiting scroll 12 presses against the fixed scroll 11 at a certain crank angle is too large, the pressing force can be weakened by communicating the pressure introduction groove 55 with the space in the intermediate pressure region B, and frictional loss can be reduced.

[0045] [1-3. Effects, etc.] As described above, the scroll compressor according to the present embodiment includes a compression mechanism unit 10 that compresses a refrigerant, an electric mechanism unit 20 that drives the compression mechanism unit 10, and a sealed container 1 that houses the compression mechanism unit 10 and the electric mechanism unit 20. The compression mechanism unit 10 includes a fixed scroll 11, an orbiting scroll 12, and a rotating shaft 13 that rotationally drives the orbiting scroll 12. The fixed scroll 11 includes a disk-shaped fixed scroll mirror plate 11a and a fixed spiral wrap 11b erected on the fixed scroll mirror plate 11a. The orbiting scroll 12 includes a disk-shaped orbiting scroll mirror plate 12a and a revolving spiral wrap 12b erected on the lap-side end face of the orbiting scroll mirror plate 12a. The fixed spiral wrap 11b and the revolving spiral wrap 12b are meshed with each other to form a plurality of compression chambers 15 between the fixed spiral wrap 11b and the revolving spiral wrap 12b. The compression chamber 15 has a first compression chamber 15A formed on the outer wall side of the revolving spiral wrap 12b and a second compression chamber 15B formed on the inner wall side of the revolving spiral wrap 12b, and is a scroll compressor that presses the orbiting scroll against the fixed scroll 11 by a back pressure formed on the non-wrap surface side of the orbiting scroll mirror plate 12a. A pressure introduction groove 55 is provided on the sliding surface of the fixed scroll 11, and a communication groove 56a is provided on the wrap surface of the orbiting scroll mirror plate 12a, and the grooves communicate with spaces of different pressures when overlapping at a certain crank angle.

[0046] According to this configuration, by controlling the pressure in pressure introduction groove 55 and the timing at which that pressure is reached, it is possible to adjust the force pressing said orbiting scroll 12 against said fixed scroll 11 in accordance with the strength of the pushing back force of said orbiting scroll 12, thereby reducing frictional resistance and providing a highly efficient scroll compressor.

[0047] Furthermore, this scroll compressor is configured such that, at the rear surface of the orbiting scroll, the pressure introducing groove 55 provided in the fixed scroll 11 does not directly communicate with the compression chamber 15. According to this configuration, when the pressure introducing groove 55 and the communication groove 56a do not overlap, there is no effect on the compression process, so that the re-expansion loss of the refrigerant and the like are suppressed, and a highly efficient scroll compressor can be achieved.

[0048] In addition, in the above-mentioned configurations, the scroll compressor is configured to communicate with the compression chamber 15 at a timing when the pressure introduction groove 55 and the communication groove 56a reach the suction pressure. According to this configuration, the pressure in the pressure introduction groove 55 and the back pressure of the orbiting scroll 12 are The difference in pressure between the first and second compression chambers 15A and 15B is large, and the force pressing the orbiting scroll 12 against the fixed scroll 11 is increased, so that the behavior of the orbiting scroll 12 can be stabilized. In addition, since the pressure of the pressure introduction groove 55 is lower than that of the first compression chamber 15A, the lubricating oil flows from the first compression chamber 15A toward the pressure introduction groove 55 on the thrust surface between the first compression chamber 15A and the pressure introduction groove 55. This prevents the lubricating oil from entering the compression chamber from the intermediate pressure space, and as a result, the amount of oil discharged is reduced, resulting in a highly efficient refrigeration system. In addition, according to this configuration, even if the lubricating oil in the intermediate pressure space accumulates at the bottom due to gravity and there is no lubricating oil at the upper side of the intermediate pressure space in a horizontal scroll compressor or the like, the lubricating oil can be supplied to the thrust surface from the compression chamber side, resulting in a highly reliable scroll compressor.

[0049] As described above, the present invention has been described using the above embodiments. However, since the above embodiments are for exemplifying the technology in the present disclosure, various changes, replacements, additions, omissions, etc. can be made within the scope of the claims or the equivalent scope thereof.

[0050] In addition, in the scroll compressor described in the above embodiment, R32, carbon dioxide, or a refrigerant having a double bond between carbons can be used.

Industrial Applicability

[0051] The scroll compressor according to the present disclosure can achieve high efficiency and is useful for various refrigeration cycle devices such as a hot water heating device, an air conditioner, a water heater, or a refrigerator.

Explanation of Signs

[0052] 1 Sealed container 2 Refrigerant suction pipe 3 Refrigerant discharge pipe 4 Oil storage part 5 Oil pump 6 Discharge chamber 10 Compression mechanism part 11 Fixed scroll 11a Fixed scroll mirror plate 11b Fixed spiral wrap 12 Orbiting scroll 12a Orbiting scroll mirror plate 12b Orbiting spiral wrap 13 Rotating shaft 13a Eccentric shaft 13b Lower end part 13c Rotating shaft oil supply hole 13d Orbiting bearing 13e Oil groove 14 Discharge port 15 Compression chamber 15a Suction port 15A First compression chamber 15B Second compression chamber 17 Self-rotation restraint member 18 Sub-bearing 20 Electric mechanism part 21 Stator 22 Rotor 30 Main bearing 31 Bearing portion 32 Boss housing portion 51 First oil inlet hole 52 First oil outlet hole 53 First mirror plate oil connection passage 54, 54a, 54b Thrust surface 55 Pressure introduction groove 56a Communication groove 56b Hole 61 Second oil inlet hole 62 Second oil outlet hole 63 Second mirror plate oil connection passage A High-pressure region B Intermediate-pressure region

Claims

【Claim 1】 A scroll compressor comprising a compression mechanism section for compressing a refrigerant, an electric mechanism section for driving the compression mechanism section, and a hermetic container for housing the compression mechanism section and the electric mechanism section, wherein the compression mechanism section has a fixed scroll, a orbiting scroll, and a rotating shaft for driving the orbiting scroll to orbit, the fixed scroll includes a disk-shaped fixed scroll mirror plate and a fixed spiral wrap erected on the fixed scroll mirror plate, the orbiting scroll includes a disk-shaped orbiting scroll mirror plate and a orbiting spiral wrap erected on the wrap-side end face of the orbiting scroll mirror plate, the fixed spiral wrap and the orbiting spiral wrap are meshed with each other to form a plurality of compression chambers between the fixed spiral wrap and the orbiting spiral wrap, the compression chambers are formed with a first compression chamber on the outer wall side of the orbiting spiral wrap and a second compression chamber on the inner wall side of the orbiting spiral wrap, and the orbiting scroll is pressed against the fixed scroll by a back pressure formed on the non-wrap surface side of the orbiting scroll mirror plate, a scroll compressor that guides lubricating oil in an oil storage section provided at the bottom of the hermetic container to the non-wrap surface side of the orbiting scroll mirror plate through a rotating shaft oil supply hole formed in the rotating shaft, wherein a pressure introduction groove is provided on the thrust surface of the fixed scroll, and a communication groove is provided on the wrap surface of the orbiting spiral scroll mirror plate, the pressure introduction groove is always set within the range where the orbiting scroll mirror plate moves and is not directly connected to the compression chamber, by communicating and disconnecting the pressure introduction groove and the communication groove, the inside of the pressure introduction groove is controlled to have a predetermined pressure for each crank angle, when the pressing force of the orbiting scroll becomes weak at a certain crank angle, the pressure introduction groove and the communication groove communicate with each other, and the pressure introduction groove is communicated with the suction space in the compression chamber, in a state where the pressure introduction groove and the communication groove communicate with each other and the pressure introduction groove is communicated with the suction space in the compression chamber, only the lubricating oil existing in the pressure introduction groove and the communication groove flows into the suction space characterized by the above.

Images