Scroll electric compressor
By setting a locking part on the partition wall of the scroll electric compressor to restrict the movement of the sealing component, the axial miniaturization and weight reduction of the rotating shaft are achieved, thus solving the problem of difficult-to-control movement of the sealing component.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- TOYOTA INDUSTRIES CORP
- Filing Date
- 2023-05-25
- Publication Date
- 2026-07-21
Smart Images
Figure CN117189602B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a scroll electric compressor. Background Technology
[0002] A scroll electric compressor includes a housing, a rotating shaft supported for rotation relative to the housing, an electric motor for rotating the rotating shaft, and a compression section. The compression section includes a fixed scroll fixed to the housing and a rotating scroll that revolves around the rotating shaft while engaging with the fixed scroll. The housing has a partition wall dividing a back pressure chamber that applies back pressure to the rotating scroll towards the fixed scroll and a motor chamber that houses the electric motor. An insertion hole for the rotating shaft is formed in the partition wall. Furthermore, the partition wall is provided with a bearing that supports the rotating shaft for rotation and an annular sealing member that seals the back pressure chamber and the motor chamber. The sealing member has an inner peripheral sealing portion that seals with the rotating shaft and an outer peripheral sealing portion that seals with the partition wall. Additionally, for example, in the scroll electric compressor described in Patent Document 1, a spring ring is used to restrict the movement of the sealing member.
[0003] Existing technical documents
[0004] Patent documents
[0005] Patent Document 1: Japanese Patent Application Publication No. 2007-128756 Summary of the Invention
[0006] The problem that the invention aims to solve
[0007] In scroll electric compressors, it is desirable to suppress the movement of the sealing components and to further reduce the axial dimension of the rotating shaft.
[0008] Solution for solving the problem
[0009] A scroll electric compressor for solving the above-mentioned problems includes: a housing; a rotating shaft supported for rotation relative to the housing; an electric motor that rotates the rotating shaft; and a compression section comprising a fixed scroll fixed to the housing and a rotary scroll revolving in response to the rotation of the rotating shaft while engaging with the fixed scroll. The housing has a partition wall dividing a back pressure chamber for applying back pressure to the rotary scroll towards the fixed scroll and a motor chamber for housing the electric motor, and forming an insertion hole for the rotating shaft to pass through. A bearing and an annular sealing member are provided in the partition wall, the bearing supporting the rotating shaft for rotation. The sealing member has an inner peripheral sealing portion that seals with the rotating shaft and an outer peripheral sealing portion that seals with the dividing wall, and seals the back pressure chamber with the motor chamber. The scroll electric compressor is characterized in that the inner peripheral sealing portion and the outer peripheral sealing portion each have an end facing the bearing side, the end of the inner peripheral sealing portion extends closer to the bearing than the end of the outer peripheral sealing portion, and the dividing wall is provided with a locking portion that opposes the end of the outer peripheral sealing portion and abuts against the end of the outer peripheral sealing portion to restrict the movement of the sealing member toward the bearing side, the end of the inner peripheral sealing portion extending closer to the bearing than the locking portion.
[0010] According to the above structure, a locking portion is provided in the dividing wall, so the end of the outer peripheral seal abuts against the locking portion, thereby restricting the movement of the sealing member toward the bearing. The end of the inner peripheral seal extends closer to the bearing than the locking portion, so the axial dimension of the outer peripheral seal on the rotating shaft is smaller than the axial dimension of the inner peripheral seal on the rotating shaft. Compared with the case where the axial dimension of the outer peripheral seal on the rotating shaft is larger than the axial dimension of the inner peripheral seal on the rotating shaft, the axial dimension of the sealing member can be reduced. Therefore, the movement of the sealing member toward the bearing can be restricted, and the scroll electric compressor can be miniaturized in the axial direction of the rotating shaft.
[0011] In a scroll electric compressor, the dimension between the end of the locking part and the end of the outer peripheral seal in the axial direction of the rotating shaft may be smaller than the dimension between the end of the bearing and the end of the inner peripheral seal in the axial direction.
[0012] According to the above structure, even if the sealing member moves towards the bearing, the end of the outer peripheral seal abuts against the locking portion before the end of the inner peripheral seal abuts against the bearing. Therefore, it is possible to prevent the end of the inner peripheral seal from abutting against the bearing, thereby preventing a decrease in the sealing performance of the inner peripheral seal on the rotating shaft.
[0013] In a scroll electric compressor, the outer diameter of the portion supported by the bearing in the rotating shaft may be the same as the outer diameter of the portion in contact with the inner circumferential seal.
[0014] The grinding of the outer circumferential surface of the rotating shaft is performed, for example, using a grinding roller. Assuming the rotating shaft has a large-diameter section with a larger outer diameter and a small-diameter section with a smaller outer diameter, in order to prevent the grinding roller from contacting the large-diameter section during the grinding process, a recess is formed at the boundary between the small-diameter and large-diameter sections to allow the grinding roller to pass. According to this structure, the outer diameter of the portion supported by the bearing in the rotating shaft is the same as the outer diameter of the portion in contact with the inner circumferential seal. Therefore, it is unnecessary to form the aforementioned recess at the boundary between the portion supported by the bearing and the portion in contact with the inner circumferential seal in the rotating shaft. As a result, corresponding to not forming the aforementioned recess, the axial dimension of the rotating shaft between the portion supported by the bearing and the portion in contact with the inner circumferential seal can be shortened. Therefore, the scroll electric compressor can be further miniaturized in the axial direction of the rotating shaft.
[0015] In a scroll electric compressor, the rotating shaft may also have a counterweight for counteracting the centrifugal force acting on the rotating scroll due to the rotation of the rotating shaft, the counterweight being disposed axially between the dividing wall and the electric motor.
[0016] According to the above structure, by extending the end of the inner circumferential seal closer to the bearing than the locking portion, the scroll electric compressor is miniaturized in the axial direction of the rotating shaft, thus allowing the counterweight to be closer to the bearing in the axial direction of the rotating shaft. By shortening the distance between the rotating scroll and the counterweight in the axial direction of the rotating shaft, the weight of the counterweight required to counteract the centrifugal force acting on the rotating scroll due to the rotation of the rotating shaft is reduced. Therefore, by reducing the weight of the counterweight, the scroll electric compressor can be made lighter.
[0017] In a scroll electric compressor, the rotating shaft may also have a counterweight for counteracting the centrifugal force acting on the rotating scroll due to the rotation of the rotating shaft, the counterweight being disposed axially between the dividing wall and the electric motor.
[0018] According to the above structure, the dimension of the rotating shaft between the portion supported by the bearing and the portion in contact with the inner circumferential seal is shortened in the axial direction of the rotating shaft, thus allowing the counterweight to be closer to the bearing in the axial direction of the rotating shaft. By shortening the distance between the rotating scroll and the counterweight in the axial direction of the rotating shaft, the weight of the counterweight required to counteract the centrifugal force acting on the rotating scroll due to the rotation of the rotating shaft is reduced. Therefore, by reducing the weight of the counterweight, the scroll electric compressor can be made lighter.
[0019] Invention Effects
[0020] According to the present invention, the movement of the sealing member toward the bearing can be restricted while the scroll electric compressor is miniaturized in the axial direction of the rotating shaft. Attached Figure Description
[0021] Figure 1 This is a cross-sectional view illustrating an embodiment of a scroll electric compressor.
[0022] Figure 2 This is a cross-sectional view showing an enlarged portion of a scroll electric compressor.
[0023] Figure 3 It is a cross-sectional view showing the periphery of the bearing and sealing components magnified.
[0024] Explanation of reference numerals in the attached figures
[0025] L2, L3: Outer diameter; L4, L5, L6, L7: Dimensions; S1: Motor chamber; S3: Back pressure chamber; X: Axial direction; 10: Scroll electric compressor; 11: Housing; 13: Shaft support housing; 15: Rotating shaft; 15b: First shaft section; 15c: Second shaft section; 17a: Through hole; 21: Bearing; 22: Electric motor; 25: Fixed scroll; 26: Rotary scroll; 30: Compression section; 32: Counterweight; 40: Sealing component; 41: Inner circumferential seal; 41a: End of (inner circumferential seal); 42: Outer circumferential seal; 42a: End of (outer circumferential seal); 45: Locking part. Detailed Implementation
[0026] Hereinafter, an embodiment of a scroll electric compressor will be described with reference to the accompanying drawings. The scroll electric compressor of this embodiment is used, for example, in a vehicle air conditioning system.
[0027] <Basic Structure of a Scroll Electric Compressor>
[0028] like Figure 1 As shown, the scroll electric compressor 10 has a cylindrical housing 11. The housing 11 includes a motor housing 12, a shaft support housing 13, and a discharge housing 14. The motor housing 12, shaft support housing 13, and discharge housing 14 are made of metal. For example, the motor housing 12, shaft support housing 13, and discharge housing 14 are made of aluminum.
[0029] The scroll electric compressor 10 has a rotating shaft 15 supported so as to be rotatable relative to the housing 11. Hereinafter, the direction in which the axis L1 of the rotating shaft 15 extends will also be referred to as the axial direction X of the rotating shaft 15.
[0030] The motor housing 12 has a plate-shaped end wall 12a and a cylindrical peripheral wall 12b. The peripheral wall 12b extends cylindrically from the outer periphery of the end wall 12a. The axial direction of the peripheral wall 12b is aligned with the axial direction X of the rotation shaft 15. A suction port 12h is formed in the peripheral wall 12b. The suction port 12h is formed in the portion of the peripheral wall 12b located near the end wall 12a. The suction port 12h connects the inside and outside of the motor housing 12. The suction port 12h draws in refrigerant gas as a fluid.
[0031] The motor housing 12 has a cylindrical boss portion 12d. The boss portion 12d protrudes from the inner surface of the end wall 12a. The first end of the rotating shaft 15, which is the end in the axial direction X, is inserted into the boss portion 12d. A rolling bearing 16 is provided between the inner circumferential surface of the boss portion 12d and the outer circumferential surface 15a at the first end of the rotating shaft 15. The first end of the rotating shaft 15 is rotatably supported on the motor housing 12 via the rolling bearing 16.
[0032] The shaft support housing 13 has a circular plate-shaped end wall 17 and a cylindrical peripheral wall 18. The peripheral wall 18 extends cylindrically from the outer periphery of the end wall 17. The axial direction of the peripheral wall 18 is aligned with the axial direction X of the rotating shaft 15. The shaft support housing 13 has an annular flange wall 19. The flange wall 19 extends radially outward from the end of the outer peripheral surface of the peripheral wall 18 opposite to the end wall 17 toward the rotating shaft 15. The outer periphery of the flange wall 19 contacts the open end of the peripheral wall 12b of the motor housing 12.
[0033] A peripheral wall recess 18a and a first receiving recess 18b are formed on the peripheral wall 18. A through hole 17a is formed on the end wall 17. That is, a through hole 17a is formed on the shaft support housing 13. Furthermore, a second receiving recess 17b is formed on the end wall 17. The axial directions of the peripheral wall recess 18a, the first receiving recess 18b, the through hole 17a, and the second receiving recess 17b are all aligned with the axial direction X of the rotating shaft 15.
[0034] The peripheral wall recess 18a opens at its end face 13e on the side opposite to the motor housing 12 within the shaft support housing 13. A first receiving recess 18b is adjacent to and communicates with the peripheral wall recess 18a along the axial direction X of the rotating shaft 15. A second receiving recess 17b is adjacent to and communicates with the first receiving recess 18b along the axial direction X of the rotating shaft 15. A through hole 17a is adjacent to and communicates with the second receiving recess 17b along the axial direction X of the rotating shaft 15.
[0035] like Figure 2As shown, the first receiving recess 18b is divided by a first side surface 18c and a first end surface 18d in the peripheral wall 18. The first end surface 18d extends orthogonally to the axial direction X of the rotation axis 15. The first side surface 18c extends from the outer edge of the first end surface 18d in the radial direction of the rotation axis 15. The second receiving recess 17b is divided by a second side surface 17c and a second end surface 17d in the end wall 17. The second end surface 17d extends orthogonally to the axial direction X of the rotation axis 15. The second side surface 17c extends from the outer edge of the second end surface 17d in the radial direction of the rotation axis 15.
[0036] An insertion hole 17a is formed in the central portion of the end wall 17. The insertion hole 17a extends through the end wall 17 in the thickness direction. A rotating shaft 15 is inserted through the insertion hole 17a. The end face 15e of the rotating shaft 15, which is the end opposite to the first end, is located inside the peripheral wall 18. The second end of the rotating shaft 15, which is inserted through the insertion hole 17a, passes through the insertion hole 17a and the second receiving recess 17b, and is located within the first receiving recess 18b.
[0037] like Figure 1 As shown, a motor chamber S1 is formed within the housing 11. The motor chamber S1 is divided by the motor housing 12 and the shaft support housing 13. The motor chamber S1 is connected to the intake port 12h. Refrigerant gas from the intake port 12h is drawn into the motor chamber S1.
[0038] The scroll-type electric compressor 10 has an electric motor 22 that rotates a rotating shaft 15. The electric motor 22 is housed in a motor chamber S1. The electric motor 22 has a cylindrical stator 23 and a cylindrical rotor 24. The rotor 24 is disposed inside the stator 23. The rotor 24 rotates integrally with the rotating shaft 15. The stator 23 surrounds the rotor 24. The rotor 24 has a rotor core 24a fixed to the rotating shaft 15 and a plurality of permanent magnets (not shown) disposed on the rotor core 24a. The stator 23 has a cylindrical stator core 23a and a coil 23b. The stator core 23a is fixed to the inner circumferential surface of the peripheral wall 12b of the motor housing 12. The coil 23b is wound around the stator core 23a. The rotor 24 rotates by supplying power controlled by an inverter (not shown) to the coil 23b. Thus, the rotating shaft 15 and the rotor 24 rotate integrally.
[0039] The discharge casing 14 has a plate-shaped end wall 14a and a cylindrical peripheral wall 14b. The peripheral wall 14b extends cylindrically from the outer periphery of the end wall 14a. The axial direction of the peripheral wall 14b is aligned with the axial direction X of the rotation shaft 15. The open end of the peripheral wall 14b contacts the outer periphery of the flange wall 19.
[0040] The discharge housing 14, the shaft support housing 13, and the motor housing 12 are secured by bolts B1. Bolts B1 penetrate the peripheral wall 14b of the discharge housing 14 and the outer periphery of the flange wall 19, and are screwed into the peripheral wall 12b of the motor housing 12. Thus, the shaft support housing 13 is connected to the peripheral wall 12b of the motor housing 12, and the discharge housing 14 is connected to the flange wall 19 of the shaft support housing 13. Therefore, the motor housing 12, the shaft support housing 13, and the discharge housing 14 are arranged in this order along the axial direction X of the rotating shaft 15.
[0041] The scroll electric compressor 10 includes a discharge chamber S2. The discharge chamber S2 is formed within a discharge housing 14. The discharge housing 14 has a discharge outlet 14h. The discharge outlet 14h is formed in the end wall 14a of the discharge housing 14. The discharge outlet 14h communicates with the discharge chamber S2. The discharge outlet 14h discharges refrigerant gas from the discharge chamber S2.
[0042] The outlet 14h and the inlet 12h are connected via an external refrigerant circuit 20. The external refrigerant circuit 20 includes a condenser, an expansion valve, and an evaporator (not shown). Refrigerant gas discharged from the outlet 14h flows through the external refrigerant circuit 20. The refrigerant gas flowing in the external refrigerant circuit 20 passes through the condenser, expansion valve, and evaporator, and then returns to the motor compartment S1 via the inlet 12h. The scroll electric compressor 10 and the external refrigerant circuit 20 constitute the vehicle's air conditioning system.
[0043] The scroll electric compressor 10 has a compression section 30. The compression section 30 includes a fixed scroll 25 and a rotary scroll 26. The fixed scroll 25 and the rotary scroll 26 are disposed inside the peripheral wall 14b of the discharge housing 14. The fixed scroll 25 is located on the axial direction X of the rotation shaft 15 closer to the end wall 14a than the rotary scroll 26.
[0044] The fixed scroll 25 is fixed to the housing 11. Specifically, the fixed scroll 25 is fixed to the end wall 14a of the discharge housing 14. The fixed scroll 25 has a fixed base plate 25a and a fixed scroll wall 25b. The fixed base plate 25a is circular. The fixed scroll wall 25b rises from the fixed base plate 25a towards the side opposite to the end wall 14a. The fixed scroll 25 has a fixed outer peripheral wall 25c. The fixed outer peripheral wall 25c rises cylindrically from the outer periphery of the fixed base plate 25a. The fixed outer peripheral wall 25c surrounds the fixed scroll wall 25b. The open end face of the fixed outer peripheral wall 25c is located on the side opposite to the fixed base plate 25a, closer to the front end face of the fixed scroll wall 25b.
[0045] The rotating scroll 26 has a rotating base plate 26a and a rotating scroll wall 26b. The rotating base plate 26a is circular. The rotating base plate 26a is opposite to the fixed base plate 25a. The rotating scroll wall 26b rises from the rotating base plate 26a toward the fixed base plate 25a. The rotating scroll wall 26b engages with the fixed scroll wall 25b. Thus, the rotating scroll 26 revolves under the action of the rotation of the rotating shaft 15 while engaging with the fixed scroll 25. The rotating scroll wall 26b is located inside the fixed outer peripheral wall 25c. The front end face of the fixed scroll wall 25b contacts the rotating base plate 26a. The front end face of the rotating scroll wall 26b contacts the fixed base plate 25a. Furthermore, a plurality of compression chambers 27 are divided by the fixed base plate 25a, the fixed scroll wall 25b, the rotating base plate 26a, and the rotating scroll wall 26b. Therefore, multiple compression chambers 27 are divided by the fixed scroll 25 and the rotating scroll 26. Each compression chamber 27 compresses the refrigerant gas.
[0046] The rotating scroll 26 has a cylindrical boss 26c. The boss 26c protrudes from the end face 26e of the rotating base plate 26a on the side opposite to the fixed base plate 25a. The axial direction of the boss 26c is aligned with the axial direction X of the rotation axis 15. A plurality of boss recesses 26d are formed around the boss 26c in the end face 26e of the rotating base plate 26a. The plurality of boss recesses 26d are arranged at predetermined intervals along the circumferential direction of the rotation axis 15. It should be noted that in Figure 1 For ease of explanation, only one boss recess 26d is shown in the diagram. A ring-shaped member 28 is embedded within each boss recess 26d. The scroll electric compressor 10 has multiple pins 29. Each pin 29 is disposed on the shaft support housing 13. Each pin 29 protrudes from the end face 13e of the shaft support housing 13. Each pin 29 is inserted into each ring member 28.
[0047] A discharge port 25h is formed in the center of the fixed substrate 25a. The discharge port 25h is circular. The discharge port 25h passes through the fixed substrate 25a along its thickness direction. The first end of the discharge port 25h communicates with the compression chamber 27. The second end of the discharge port 25h communicates with the discharge chamber S2. The discharge port 25h discharges the refrigerant gas compressed by the compression chamber 27 into the discharge chamber S2. A valve mechanism 50 is installed on the side of the fixed substrate 25a opposite to the fixed scroll wall 25b. The valve mechanism 50 is configured to open and close the discharge port 25h.
[0048] The scroll electric compressor 10 includes an eccentric shaft 31. The eccentric shaft 31 protrudes from an eccentric portion of the end face 15e of the rotating shaft 15 relative to the axis L1 of the rotating shaft 15 toward the rotating scroll 26. The eccentric shaft 31 is integrally formed with the rotating shaft 15. The axial direction of the eccentric shaft 31 is aligned with the axial direction X of the rotating shaft 15. The eccentric shaft 31 is inserted into the boss portion 26c.
[0049] The rotating shaft 15 includes a counterweight 32. The counterweight 32 is integrally formed with the rotating shaft 15. The counterweight 32 is positioned eccentrically from the axis L1 of the rotating shaft 15. More specifically, the counterweight 32 is positioned on the opposite side of the eccentric shaft 31, separated from the axis L1 of the rotating shaft 15. The counterweight 32 is formed as a generally fan-shaped plate. The counterweight 32 extends radially outward from the rotating shaft 15. That is, the counterweight 32 extends from the rotating shaft 15 toward the peripheral wall 12b of the motor housing 12.
[0050] The counterweight 32 comprises a base end 32a, an inclined portion 32b, and a front end 32c. The base end 32a is connected to the rotation shaft 15 and extends from the rotation shaft 15 in a substantially perpendicular manner relative to the rotation shaft 15. The inclined portion 32b is connected to the base end 32a. The inclined portion 32b extends obliquely such that the further away from the base end 32a in the radial direction of the rotation shaft 15, the closer it is to the shaft support housing 13. The front end 32c is connected to the inclined portion 32b and extends from the inclined portion 32b in a substantially perpendicular manner relative to the rotation shaft 15.
[0051] The counterweight 32 is disposed within the housing 11 via the rotating shaft 15, thereby being located within the motor chamber S1. The counterweight 32 is positioned along the axial direction X of the rotating shaft 15 between the shaft support housing 13, which serves as a dividing wall, and the electric motor 22.
[0052] The rotating scroll 26 is rotatably supported on the eccentric shaft 31 via the bushing 33 and rolling bearing 34. The rotation of the rotating shaft 15 is transmitted to the rotating scroll 26 via the eccentric shaft 31, bushing 33, and rolling bearing 34, causing the rotating scroll 26 to rotate. Furthermore, the rotation of the rotating scroll 26 is prevented by the contact between each pin 29 and the inner circumferential surface of each ring member 28, allowing only its revolution. Thus, the rotating scroll 26 revolves while the rotating scroll wall 26b is in contact with the fixed scroll wall 25b, reducing the volume of the compression chamber 27 and compressing the refrigerant gas. Therefore, the rotating scroll 26 revolves along with the rotation of the rotating shaft 15. A counterweight 32 is used to counteract the centrifugal force acting on the rotating scroll 26 due to the rotation of the rotating shaft 15. In detail, the counterweight 32 counteracts the centrifugal force acting on the rotary volute 26 when it is revolving, thereby reducing the imbalance of the rotary volute 26.
[0053] The scroll-type electric compressor 10 includes a first groove 35, a first hole 36, and a second groove 37. Multiple first grooves 35 are formed on the inner circumferential surface of the peripheral wall 12b of the motor housing 12. Each first groove 35 opens at its open end in the peripheral wall 12b. Multiple first holes 36 are formed on the outer circumferential portion of the flange wall 19 of the shaft support housing 13. Each first hole 36 penetrates the flange wall 19 along its thickness direction. Each first hole 36 communicates with each first groove 35. Multiple second grooves 37 are formed on the inner circumferential surface of the peripheral wall 14b of the discharge housing 14. Each second groove 37 communicates with each first hole 36. It should be noted that... Figure 1 For ease of illustration, one of each of the first groove 35, the first hole 36, and the second groove 37 is shown in the diagram.
[0054] The fixed scroll plate 25 has multiple intake ports 38. It should be noted that... Figure 1 For ease of illustration, a suction port 38 is shown. Each suction port 38 is formed on the fixed outer peripheral wall 25c of the fixed scroll 25. Each suction port 38 penetrates the fixed outer peripheral wall 25c along its thickness direction. Each suction port 38 is connected to each second groove 37. For example, two suction ports 38 are formed on the fixed outer peripheral wall 25c at circumferentially spaced 180 degrees apart.
[0055] The scroll electric compressor 10 includes a suction chamber 39. The suction chamber 39 is connected to two suction ports 38. The suction chamber 39 is formed inside a fixed outer peripheral wall 25c. The suction chamber 39 is a space within the fixed outer peripheral wall 25c that communicates with at least one of the two suction ports 38 as the rotating scroll 26 revolves. Depending on the position of the rotating scroll 26, the suction chamber 39 may communicate with one of the two suction ports 38 but not with the other. Furthermore, depending on the position of the rotating scroll 26, the suction chamber 39 may also communicate with both of the two suction ports 38.
[0056] The refrigerant gas in the motor chamber S1 is drawn into the intake chamber 39 through the first slots 35, the first holes 36, the second slots 37, and the intake ports 38. The refrigerant gas drawn into the intake chamber 39 is compressed in the compression chamber 27 by the revolution of the rotating scroll 26.
[0057] A back pressure chamber S3 is formed within the housing 11. The back pressure chamber S3 is located inside the peripheral wall 18 of the shaft support housing 13. Therefore, the back pressure chamber S3 is formed on the side of the housing 11 opposite to the fixed plate 25a relative to the rotating plate 26a. The shaft support housing 13 functions as a dividing wall separating the back pressure chamber S3 from the motor chamber S1.
[0058] A back pressure inlet passage 26f is formed in the rotating scroll 26. The back pressure inlet passage 26f passes through the rotating base plate 26a and the rotating scroll wall 26b. The back pressure inlet passage 26f introduces a portion of the refrigerant gas in the compression chamber 27 into the back pressure chamber S3. Because a portion of the refrigerant gas in the compression chamber 27 is introduced through the back pressure inlet passage 26f, the back pressure chamber S3 becomes higher than the motor chamber S1. The back pressure chamber S3 provides back pressure for applying force to the rotating scroll 26 toward the fixed scroll 25. Specifically, the pressure in the back pressure chamber S3 increases, so that the rotating scroll 26 is pressed toward the fixed scroll 25 by the front end face of the rotating scroll wall 26b being pressed against the fixed base plate 25a.
[0059] <Bearing>
[0060] like Figure 2 As shown, a bearing 21 is provided in the shaft support housing 13, which serves as a dividing wall, to support the rotating shaft 15 so that it can rotate. In this embodiment, the bearing 21 is a rolling bearing. The bearing 21 is located within the first receiving recess 18b of the peripheral wall 18. The bearing 21 is disposed between the first side surface 18c of the peripheral wall 18 and the outer peripheral surface 15a of the rotating shaft 15. The bearing 21 is fixed to the first side surface 18c and the first end surface 18d of the peripheral wall 18.
[0061] The bearing 21 supports a portion of the axial direction X of the rotating shaft 15. The portion of the rotating shaft 15 supported by the bearing 21 is also referred to as the first shaft portion 15b. The rotating shaft 15 is rotatably supported to the shaft support housing 13 via the bearing 21. Therefore, the rotating shaft 15 is supported so that it can rotate relative to the housing 11.
[0062] <Sealing Components>
[0063] An annular sealing member 40 is provided in the shaft support housing 13, which serves as a dividing wall. The sealing member 40 is made of resin. The sealing member 40 is located within the second receiving recess 17b of the end wall 17. The sealing member 40 is disposed between the second side surface 17c of the end wall 17 and the outer peripheral surface 15a of the rotating shaft 15. The sealing member 40 is positioned in the axial direction X of the rotating shaft 15 closer to the motor chamber S1 than the bearing 21.
[0064] The sealing member 40 contacts the second side 17c of the end wall 17. The sealing member 40 also contacts a portion of the axial direction X of the rotating shaft 15. The portion of the rotating shaft 15 in contact with the sealing member 40 is also referred to as the second shaft portion 15c. It should be noted that the outer diameter L2 of the first shaft portion 15b and the outer diameter L3 of the second shaft portion 15c are the same size. Between the first shaft portion 15b and the second shaft portion 15c in the axial direction X of the rotating shaft 15, the outer diameter of the rotating shaft 15 is the same size.
[0065] The sealing member 40 seals the back pressure chamber S3 and the motor chamber S1 by contacting the shaft support housing 13 and the rotating shaft 15. Therefore, the sealing member 40 inhibits the flow of refrigerant gas between the back pressure chamber S3 and the motor chamber S1 via the second receiving recess 17b and the through hole 17a.
[0066] When the pressure in the back pressure chamber S3 of the scroll electric compressor 10 is higher than the pressure in the motor chamber S1 in a stable state, the sealing member 40 is pressed against the second end face 17d of the second receiving recess 17b under the action of the pressure difference between the motor chamber S1 and the back pressure chamber S3.
[0067] like Figure 3 As shown, the sealing member 40 has an inner peripheral sealing portion 41 and an outer peripheral sealing portion 42. Furthermore, the sealing member 40 has an annular connecting portion 43. The connecting portion 43 extends radially along the rotation axis 15. The connecting portion 43 connects the inner peripheral sealing portion 41 and the outer peripheral sealing portion 42. The inner peripheral sealing portion 41, the outer peripheral sealing portion 42, and the connecting portion 43 are integrally formed together.
[0068] The inner circumferential seal 41 is annular. The inner circumferential seal 41 extends from the inner circumferential edge of the connecting portion 43 toward the bearing 21, and extends in such a way that the further away from the connecting portion 43 it is, the closer it is to the outer circumferential surface 15a of the rotating shaft 15.
[0069] The inner circumferential seal 41 has an end portion 41a facing the bearing 21. The end portion 41a of the inner circumferential seal 41 is located on the side opposite to the connecting portion connected to the connecting portion 43 in the inner circumferential seal 41. The portion of the end portion 41a of the inner circumferential seal 41 near the inner circumferential surface of the inner circumferential seal 41 functions as a contact portion 41b that contacts the outer circumferential surface 15a of the rotating shaft 15. By making the contact portion 41b tightly adhere to the outer circumferential surface 15a of the rotating shaft 15, the inner circumferential seal 41 seals with the rotating shaft 15. The portion in the rotating shaft 15 that is contacted by the contact portion 41b corresponds to the second shaft portion 15c in the rotating shaft 15 that is in contact with the sealing member 40.
[0070] The outer peripheral seal 42 is annular. The outer peripheral seal 42 is positioned radially outward of the inner peripheral seal 41 relative to the rotation axis 15. The outer peripheral seal 42 extends from the outer periphery of the connecting portion 43 toward the bearing 21. The outer peripheral seal 42 has an end portion 42a facing the bearing 21. The end portion 42a of the outer peripheral seal 42 is located on the side of the outer peripheral seal 42 opposite to the connecting portion connected to the connecting portion 43.
[0071] The outer peripheral surface of the outer peripheral sealing portion 42 is in close contact with the second side surface 17c of the end wall 17. The sealing member 40 is inserted into the second receiving recess 17b with the outer peripheral surface of the outer peripheral sealing portion 42 in close contact with the second side surface 17c of the end wall 17. By making the outer peripheral surface of the outer peripheral sealing portion 42 in close contact with the second side surface 17c of the end wall 17, the outer peripheral sealing portion 42 seals the space between itself and the shaft support housing 13, which serves as a dividing wall.
[0072] With the sealing member 40 embedded in the second receiving recess 17b, the end portion 41a of the inner circumferential sealing portion 41 and the end portion 42a of the outer circumferential sealing portion 42 are opposite to the bearing 21 in the axial direction X of the rotation shaft 15. The dimension L4 between the bearing 21 and the end portion 41a of the inner circumferential sealing portion 41 in the axial direction X of the rotation shaft 15 is shorter than the dimension L5 between the bearing 21 and the end portion 42a of the outer circumferential sealing portion 42 in the axial direction X of the rotation shaft 15. Therefore, in the axial direction X of the rotation shaft 15, the end portion 41a of the inner circumferential sealing portion 41 extends closer to the bearing 21 than the end portion 42a of the outer circumferential sealing portion 42.
[0073] <Standing section>
[0074] The shaft support housing 13 has a protrusion 46 that protrudes from the second side 17c of the end wall 17 toward the rotating shaft 15. The protrusion 46 is annular. The protrusion 46 is located closer to the bearing 21 than the outer peripheral seal 42 in the axial direction X of the rotating shaft 15. The protrusion 46 has a locking portion 45 that faces the end 42a of the outer peripheral seal 42. That is, the locking portion 45 is provided in the shaft support housing 13, which serves as a dividing wall. The locking portion 45 is integrally formed with the shaft support housing 13. The locking portion 45 is the end face of the protrusion 46 in the axial direction X of the rotating shaft 15 and is an annular plane. The locking portion 45 faces the end 42a of the outer peripheral seal 42. The locking portion 45 restricts the movement of the sealing member 40 toward the bearing 21 side by abutting against the end 42a of the outer peripheral seal 42.
[0075] <Location and dimensions of the sealing part>
[0076] The dimension L7 between the locking portion 45 and the end 42a of the outer peripheral seal portion 42 in the axial direction X of the rotation shaft 15 is smaller than the dimension L4 between the bearing 21 and the end 41a of the inner peripheral seal portion 41 in the axial direction X of the rotation shaft 15. The dimension L4 between the bearing 21 and the end 41a of the inner peripheral seal portion 41 in the axial direction X of the rotation shaft 15 is shorter than the dimension L6 between the bearing 21 and the locking portion 45 in the axial direction X of the rotation shaft 15. Therefore, the end 41a of the inner peripheral seal portion 41 extends closer to the bearing 21 than the locking portion 45. The dimension of the outer peripheral seal portion 42 in the axial direction X of the rotation shaft 15 is smaller than the dimension of the inner peripheral seal portion 41 in the axial direction X of the rotation shaft 15.
[0077] If the inner circumferential seal 41 is too large in the axial direction X of the rotating shaft 15, it may over-contact with the rotating shaft 15. If the inner circumferential seal 41 is too small in the axial direction X of the rotating shaft 15, the sealing member 40 may detach from the second receiving recess 17b. Therefore, in this embodiment, the size of the inner circumferential seal 41 in the axial direction X of the rotating shaft 15 is set to a size that can suppress the aforementioned over-contact of the inner circumferential seal 41 with the rotating shaft 15 and the detachment of the sealing member 40 from the second receiving recess 17b.
[0078] The larger of the dimensions of the inner circumferential sealing portion 41 and the outer circumferential sealing portion 42 in the axial direction of the rotating shaft 15 becomes the dimension of the sealing member 40 in the axial direction of the rotating shaft 15. In this embodiment, the dimension of the outer circumferential sealing portion 42 in the axial direction of the rotating shaft 15 is smaller than the dimension of the inner circumferential sealing portion 41 in the axial direction of the rotating shaft 15; therefore, the dimension of the inner circumferential sealing portion 41 in the axial direction of the rotating shaft 15 becomes the dimension of the sealing member 40 in the axial direction of the rotating shaft 15.
[0079] [The Role of the Implementation Method]
[0080] Next, the function of this embodiment will be explained.
[0081] In the scroll electric compressor 10, for example, when filling the interior of the scroll electric compressor 10 with refrigerant gas, a vacuuming operation is performed to extract air from the interior of the scroll electric compressor 10 before filling with refrigerant gas. After the vacuuming operation, refrigerant gas is gradually filled from the motor chamber S1. Furthermore, when the pressure in the motor chamber S1 becomes unstable and higher than the pressure in the back pressure chamber S3, the pressure difference between the motor chamber S1 and the back pressure chamber S3 can cause air to be drawn from the motor chamber S1. Figure 3 As shown by the double-dotted line, the sealing member 40 moves toward the bearing 21. At this time, the end 42a of the outer peripheral sealing part 42 abuts against the locking part 45, thereby restricting the movement of the sealing member 40 toward the bearing 21.
[0082] [Effects of the Implementation Method]
[0083] The following effects can be obtained from the above embodiments.
[0084] (1) A locking portion 45 is provided in the shaft support housing 13, which serves as a dividing wall, to oppose the end 42a of the outer peripheral seal 42 and to restrict the movement of the sealing member 40 toward the bearing 21 by abutting against the end 42a of the outer peripheral seal 42. Therefore, by abutting against the locking portion 45, the movement of the sealing member 40 toward the bearing 21 is restricted. The end 41a of the inner peripheral seal 41 extends closer to the bearing 21 than the locking portion 45. Therefore, the dimension of the outer peripheral seal 42 in the axial direction X of the rotating shaft 15 is smaller than the dimension of the inner peripheral seal 41 in the axial direction X of the rotating shaft 15. Compared with the case where the dimension of the outer peripheral seal 42 in the axial direction X of the rotating shaft 15 is larger than the dimension of the inner peripheral seal 41 in the axial direction X of the rotating shaft 15, the dimension of the sealing member 40 in the axial direction X of the rotating shaft 15 can be reduced. Therefore, while restricting the movement of the sealing member 40 toward the bearing 21, the scroll electric compressor 10 can be miniaturized in the axial direction X of the rotating shaft 15.
[0085] (2) The dimension L7 between the locking portion 45 and the end 42a of the outer peripheral sealing portion 42 in the axial direction X of the rotating shaft 15 is smaller than the dimension L4 between the bearing 21 and the end 41a of the inner peripheral sealing portion 41 in the axial direction X of the rotating shaft 15. Therefore, even if the sealing member 40 moves toward the bearing 21, the end 42a of the outer peripheral sealing portion 42 abuts against the locking portion 45 before the end 41a of the inner peripheral sealing portion 41 abuts against the bearing 21. Therefore, it is possible to prevent the end 41a of the inner peripheral sealing portion 41 from abutting against the bearing 21, and thus it is possible to suppress the decrease in the sealing performance of the inner peripheral sealing portion 41 on the rotating shaft 15.
[0086] (3) The outer diameter L2 of the first shaft portion 15b, which is supported by the bearing 21, and the outer diameter L3 of the second shaft portion 15c, which is in contact with the inner circumferential seal 41, are the same size. Therefore, it is not necessary to form a recess at the boundary between the first shaft portion 15b and the second shaft portion 15c in the rotating shaft 15 to avoid the grinding roller when grinding the rotating shaft 15. As a result, corresponding to not forming the aforementioned recess, the size of the rotating shaft 15 between the first shaft portion 15b and the second shaft portion 15c can be shortened in the axial direction X of the rotating shaft 15. Therefore, the scroll electric compressor 10 can be further miniaturized in the axial direction X of the rotating shaft 15.
[0087] (4) The rotating shaft 15 is equipped with a counterweight 32 for counteracting the centrifugal force acting on the rotary scroll 26 due to the rotation of the rotating shaft 15. The counterweight 32 is disposed in the axial direction X of the rotating shaft 15 between the shaft support housing 13, which serves as a dividing wall, and the electric motor 22. By extending the end 41a of the inner circumferential seal 41 closer to the bearing 21 than the locking part 45, the scroll electric compressor 10 is miniaturized in the axial direction X of the rotating shaft 15, thus allowing the counterweight 32 to be closer to the bearing 21 in the axial direction X of the rotating shaft 15. By shortening the distance between the rotary scroll 26 and the counterweight 32 in the axial direction X of the rotating shaft 15, the weight of the counterweight 32 required to counteract the centrifugal force acting on the rotary scroll 26 due to the rotation of the rotating shaft 15 is reduced. Therefore, by reducing the weight of the counterweight 32, the scroll electric compressor 10 can be made lighter.
[0088] (5) The rotating shaft 15 is equipped with a counterweight 32 for counteracting the centrifugal force acting on the rotary scroll 26 due to the rotation of the rotating shaft 15. The counterweight 32 is disposed in the axial direction X of the rotating shaft 15 between the shaft support housing 13, which serves as a dividing wall, and the electric motor 22. In the axial direction X of the rotating shaft 15, the dimension of the rotating shaft 15 between the first shaft portion 15b, which is supported by the bearing 21, and the second shaft portion 15c, which is in contact with the inner circumferential seal portion 41, is shortened. Therefore, the counterweight 32 can be brought closer to the bearing 21 in the axial direction X of the rotating shaft 15. By shortening the distance between the rotary scroll 26 and the counterweight 32 in the axial direction X of the rotating shaft 15, the weight of the counterweight 32 required to counteract the centrifugal force acting on the rotary scroll 26 due to the rotation of the rotating shaft 15 is reduced. Therefore, by reducing the weight of the counterweight 32, the scroll electric compressor 10 can be made lighter.
[0089] [Example of Change]
[0090] It should be noted that the above embodiments can be modified as follows. The above embodiments and the following modifications can be combined with each other within the scope of technical inconsistency.
[0091] The counterweight 32 is not limited to being positioned between the shaft support housing 13 and the electric motor 22 on the axial direction X of the rotating shaft 15. For example, the counterweight 32 can also be positioned in the back pressure chamber S3.
[0092] ○ The counterweight 32 can also be omitted from the rotating shaft 15.
[0093] The outer diameter L2 of the first shaft portion 15b may be larger or smaller than the outer diameter L3 of the second shaft portion 15c. In this case, a recess for avoiding the grinding roller may be formed at the boundary between the first shaft portion 15b and the second shaft portion 15c in the rotating shaft 15.
[0094] The dimension L7 between the end 42a of the locking part 45 and the outer peripheral sealing part 42 in the axial direction X of the rotating shaft 15 can also be greater than or equal to the dimension L4 between the end 41a of the bearing 21 and the inner peripheral sealing part 41 in the axial direction X of the rotating shaft 15.
[0095] The locking portion 45 can also be separate from the shaft support housing 13. For example, the locking portion 45 can be separated from the shaft support housing 13 by providing a spring ring as a dividing wall and providing the locking portion 45 on the spring ring. In this case, for example, an annular groove is formed on the second side 17c of the end wall 17, and the spring ring is fitted into the groove. The locking portion 45 in the spring ring is the end face of the spring ring in the axial direction X of the rotating shaft 15 and is an annular plane. In this case, the locking portion 45 also faces the end 42a of the outer peripheral sealing portion 42.
[0096] ○ Bearing 21 may not be a rolling bearing. For example, bearing 21 may also be a sliding bearing.
[0097] In this embodiment, the scroll electric compressor 10 is used in a vehicle air conditioning system, but is not limited thereto. For example, the scroll electric compressor 10 can also be installed in a fuel cell vehicle and compress air as a fluid supplied to the fuel cell.
Claims
1. A scroll electric compressor, comprising: case; A rotating shaft, which is supported so as to be rotatable relative to the housing; An electric motor that rotates the rotating shaft; and The compression section includes a fixed scroll plate fixed to the housing and a rotary scroll plate that revolves under the action of the rotation of the rotating shaft while meshing with the fixed scroll plate. The housing has a dividing wall that separates a back pressure chamber for applying back pressure to the rotating scroll towards the fixed scroll and a motor chamber for housing the electric motor, and forms an insertion hole for the rotating shaft to pass through. A bearing and an annular sealing member are provided on the dividing wall. The bearing supports the rotating shaft to enable rotation, and the sealing member has an inner peripheral sealing portion that seals with the rotating shaft and an outer peripheral sealing portion that seals with the dividing wall, and seals the back pressure chamber and the motor chamber. The scroll electric compressor is characterized in that... The inner circumferential seal and the outer circumferential seal each have an end facing the bearing side, and the end of the inner circumferential seal extends closer to the bearing than the end of the outer circumferential seal. The dividing wall is provided with a locking part that opposes the end of the outer peripheral sealing part and abuts against the end of the outer peripheral sealing part to restrict the movement of the sealing member toward the bearing side. The end of the inner circumferential seal is positioned closer to the bearing than the locking portion. In the case of an unstable state where the pressure in the motor chamber of the scroll electric compressor is higher than the pressure in the back pressure chamber, the end of the outer peripheral seal contacts the locking portion to restrict the movement of the sealing member toward the bearing side. When the pressure in the back pressure chamber of the scroll electric compressor is higher than the pressure in the motor chamber in a stable state, the end of the outer peripheral seal does not contact the locking part.
2. The scroll electric compressor according to claim 1, wherein, The dimension between the end of the locking portion and the end of the outer peripheral seal portion in the axial direction of the rotating shaft is smaller than the dimension between the end of the bearing and the end of the inner peripheral seal portion in the axial direction.
3. The scroll electric compressor according to claim 1 or 2, wherein, The outer diameter of the portion supported by the bearing in the rotating shaft is the same as the outer diameter of the portion in contact with the inner circumferential seal.
4. The scroll electric compressor according to claim 1 or 2, wherein, The rotating shaft is equipped with a counterweight to counteract the centrifugal force acting on the rotating scroll due to the rotation of the rotating shaft. The counterweight is positioned axially between the dividing wall and the electric motor on the rotating shaft.
5. The scroll electric compressor according to claim 3, wherein, The rotating shaft is equipped with a counterweight to counteract the centrifugal force acting on the rotating scroll due to the rotation of the rotating shaft. The counterweight is positioned axially between the dividing wall and the electric motor on the rotating shaft.