Motors and motor systems

Abstract

To provide a technique for stably cooling a terminal unit.SOLUTION: A motor disclosed in this specification includes a case, a stator fixed in the case and having a stator coil, a rotor rotatably supported in the case and facing the stator, and a terminal unit provided in an opening formed in the case. The terminal unit is fixed in the opening and has a main body at least a part of which is made of an insulating material, and an external connection terminal held by the main body, extending from the inside to the outside of the case, and electrically connected to the stator coil within the case. The main body of the terminal unit is provided with an oil flow path that communicates between the inside and the outside of the case and is configured to supply oil into the case.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The technology disclosed in this specification relates to motors and motor systems.

Background Art

[0002] Patent Document 1 discloses a motor provided with a terminal unit. The terminal unit is provided with an external connection terminal and an oil flow path for cooling the external connection terminal. The oil supplied into the motor case flows along the outer peripheral surface of the stator and then is supplied to the oil flow path of the terminal unit.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above - described motor, the oil after cooling the stator is supplied to the oil flow path of the terminal unit. Therefore, the temperature of the oil supplied to the terminal unit is relatively high, and there is a possibility that the terminal unit cannot be sufficiently cooled. This specification provides a technology capable of stably cooling the terminal unit.

Means for Solving the Problems

[0005] A motor disclosed herein comprises a case, a stator fixed within the case and having a stator coil, a rotor rotatably supported within the case and facing the stator, and a terminal unit provided in an opening formed in the case. The terminal unit is fixed in the opening and has a body that is at least partly made of an insulating material, and an external connection terminal held by the body that extends both inside and outside the case and is electrically connected to the stator coil within the case. The body of the terminal unit is provided with an oil passage that connects the inside and outside of the case and is configured to supply oil into the case.

[0006] In the vehicle described above, the terminal unit body is provided with an oil passage that connects the inside and outside of the case. This allows oil to be directly supplied to the terminal unit's oil passage from outside the case. By supplying low-temperature oil to the terminal unit, the terminal unit can be cooled stably.

[0007] Details of the technology disclosed herein and further improvements are described in the following "Modes for Carrying Out the Invention". [Brief explanation of the drawing]

[0008] [Figure 1] The circuit diagram of the motor system 100 of the first embodiment is shown. [Figure 2] A cross-sectional view of the motor 10 of the first embodiment is shown. [Figure 3] This shows an enlarged view of the area within line III in Figure 2. [Figure 4] Figure 3 shows a cross-sectional view along line IV-IV. [Figure 5] This shows an enlarged view of the same part as in Figure 3 of the motor 10 of the second embodiment. [Figure 6] Figure 5 shows a cross-sectional view along line VI-VI. [Modes for carrying out the invention]

[0009] In one embodiment of this technology, the oil passage may have an oil discharge port that is open towards the stator coil within the case. With this configuration, the oil discharged from the oil discharge port can cool the stator coil.

[0010] In one embodiment of this technology, an oil reservoir with a locally enlarged cross-sectional area may be formed in the intermediate section of the oil flow path. In this case, the oil reservoir may be closer to the external connection terminal than other sections of the oil flow path. With this configuration, more oil can be supplied to and recovered from the external connection terminal, which generates heat when energized, and the external connection terminal, which is the heat source, can be effectively cooled.

[0011] Furthermore, a motor system comprising the aforementioned motor and an oil supply device connected to the oil passage outside the case and supplying oil to the oil passage is also novel and useful.

[0012] (First embodiment) Figure 1 schematically shows the circuit diagram of the motor system 100 of the first embodiment. The motor system 100 is mounted on the front component of the electric vehicle 1. The motor system 100 comprises a radiator 2, a water pump 4, refrigerant piping 3, an oil cooler 6, an oil pump 8, oil piping 7, and a motor 10. The motor system 100 is a system for properly operating the motor 10 by maintaining the motor 10 at an appropriate temperature. The coordinate axes in the figure indicate directions as viewed from an occupant seated in the driver's seat of the electric vehicle 1. That is, the positive Z-axis indicates the upper side of the electric vehicle 1, and the negative Z-axis indicates the lower side. The positive Y-axis indicates the right side of the electric vehicle 1, and the negative Y-axis indicates the left side. The positive X-axis indicates the rear side of the electric vehicle 1, and the negative X-axis indicates the front side.

[0013] The radiator 2 is a device that performs heat exchange between the refrigerant (e.g., antifreeze) flowing through the refrigerant piping 3 and the outside air. The radiator 2 is exposed at the front of the electric vehicle 1. This allows the radiator 2 to take in outside air when the electric vehicle 1 is running. The water pump 4 is a device that circulates the refrigerant in the refrigerant piping 3. The water pump 4 circulates the refrigerant in the refrigerant piping 3 to the radiator 2 and then to the oil cooler 6. The oil cooler 6 is a device that performs heat exchange between the refrigerant in the refrigerant piping 3 and the oil in the oil piping 7.

[0014] The oil pump 8 is a device that circulates the oil in the oil piping 7. The oil pump 8 circulates the oil in the oil piping 7 in the order of oil cooler 6 and motor 10. The oil is cooled by a refrigerant in the oil cooler 6. The cooled oil is supplied to the motor 10.

[0015] The detailed structure of the motor 10 will be described with reference to Figure 2. Figure 2 shows a cross-sectional view of the motor 10 along a plane passing through the rotation axis of the motor 10. The motor 10 comprises a case 15, a shaft 11, a rotor 13, a stator 16, and a terminal unit 20. The motor 10 is a drive motor for the electric vehicle 1 and is a so-called radial gap type motor. The motor 10 also functions as a generator using the regenerative energy of the electric vehicle 1. The case 15 is made of, for example, aluminum. The case 15 forms an internal space 15s that houses each of the components 11, 13, and 16. The case 15 has a substantially cylindrical shape that extends in the axial direction (i.e., the left-right direction in the plane of Figure 2). The case 15 has a cap 15c. With each of the components 11, 13, 16, and 20 housed inside the case 15, the cap 15c is attached from the rear (i.e., the right side of the plane of Figure 2). This creates an internal space 15s that accommodates each of the components 11, 13, 16, and 20. An opening 15h is formed on the side of the case 15 (i.e., the upper side of the paper in Figure 2). The opening 15h penetrates the side wall of the case 15 and connects the inside and outside of the case 15.

[0016] The shaft 11 is rotatably supported in the case 15 via a pair of bearings 12F and 12R. The shaft 11 passes through the rotor 13. The rotor 13 has a cylindrical shape and is formed by laminating electrical steel sheets (e.g., silicon steel sheets). Permanent magnets 14 are embedded in the rotor 13.

[0017] The stator 16 is fixed within the case 15 and comprises a stator core 17 and stator coils 18. The stator core 17 has a cylindrical shape. The shaft 11 and rotor 13 are positioned in through holes in the stator core 17. The shaft 11, rotor 13, and stator core 17 are positioned so that their axes coincide. The stator core 17 faces the rotor 13 from the radially outer side. Similar to the rotor 13, the stator core 17 is formed by laminating electrical steel sheets (e.g., silicon steel sheets). Stator coils 18 are wound around the stator core 17 from both sides in the axial direction (i.e., left-right direction in the plane of the paper in Figure 2). The stator coils 18 consist of three phases (U phase, V phase, W phase) of coil wires. Although not shown in the illustration, the stator coils 18 are constructed by sequentially repeating the wound coil wires of each phase in the circumferential direction of the stator 16.

[0018] When current flows through the stator coil 18, a magnetic force is generated between it and the permanent magnet 14 of the rotor 13, causing the rotor 13 to rotate around the shaft 11. In this way, the rotor 13 is rotatably supported within the case 15. Details of the technology by which the motor 10 rotates the rotor 13 are known and therefore will not be explained.

[0019] The terminal unit 20 is fixed to the opening 15h of the case 15. The terminal unit 20 is connected to the oil pipe 7. Thereby, the oil 70 is supplied into the case 15 through the terminal unit 20. The oil 70 falls along the surfaces of the rear end of the stator coil 18, the bearing 12R, and the shaft 11. At this time, the oil 70 cools the stator coil 18 and reduces the frictional force on the surfaces of the bearing 12R and the shaft 11. That is, in addition to cooling the stator coil 18, the oil 70 also functions as a lubricant for the bearing 12R and the shaft 11. When it falls to the bottom surface of the case 15, the oil 72 accumulates on the bottom surface of the case 15. The oil 72 accumulated on the bottom surface of the case 15 is pumped by an oil pump 8 (see FIG. 1) through the oil pipe 7 to the oil cooler 6. The oil cooled by the oil cooler 6 is supplied again into the case 15 through the oil pipe 7 and the terminal unit 20. [[ID=!]]

[0020] Referring to FIGS. 3 and 4, the detailed structure of the terminal unit 20 will be described. The terminal unit 20 includes a main body 22, a first bus bar 24, a seal 26, and a second bus bar 42. The terminal unit 20 is a unit for electrically connecting the stator coil 18 in the case 15 and the power line 40 outside the case 15. The power line 40 is connected to, for example, a battery (not shown) disposed outside the case 15.

[0021] The main body 22 is made of resin and is press-fitted into the opening 15h of the case 15 from above. The seal 26 is an O-ring that seals between the inner peripheral surface of the opening 15h of the case 15 and the outer peripheral surface of the main body 22 of the terminal unit 20. That is, the main body 22 of the terminal unit 20 is a member that closes the opening 15h of the case 15.

[0022] A first connecting member 19 is provided at the rear end of the stator coil 18. The front end of the first connecting member 19 is connected to the coil wire of the stator coil 18, and the rear end is connected to a second connecting member 44. Each connecting member 19 and 44 is made of a conductive material (for example, copper). The second connecting member 44 is connected to a second busbar 42 by a bolt B1 and a nut N1.

[0023] The second busbar 42 has a horizontal portion that abuts the second connecting member 44, an inclined portion that is displaced forward as it rises from the front end of the horizontal portion, and a vertical portion that extends upward from the front end of the inclined portion. The second busbar 42 is a flat plate-like member and is made of a conductive material (for example, copper). The vertical portion of the second busbar 42 is connected to the first busbar 24 by a bolt B1 and a nut N1.

[0024] The first busbar 24 has a lower holding portion that abuts against the vertical portion of the second busbar 42, a body portion that extends upward from the seating surface, and an upper holding portion that bends forward at the upper end of the body portion. Power lines 40 are arranged on the upper surface of the upper holding portion of the first busbar 24 and are fixed to the main body 22 by bolts B1 and nuts N1. Similar to the second busbar 42, the first busbar 24 is also a flat plate-like member and is made of a conductive material (for example, copper).

[0025] As shown in Figure 3, the first busbar 24 extends vertically through the opening 15h of the case 15. That is, the first busbar 24 extends both inside and outside the case 15. The first busbar 24 is also connected to the second busbar 42 inside the case 15. As previously mentioned, the second busbar 42 and the respective connecting members 19 and 44 are made of conductive material. That is, the first busbar 24 is electrically connected to the stator coil 18 inside the case 15.

[0026] High voltage power flows through each connecting member 19, 44 and each busbar 24, 42 that are electrically connected to the stator coil 18. When high voltage power flows, each connecting member 19, 44 and each busbar 24, 42 generates heat.

[0027] The main body 22 of the terminal unit 20 is provided with an oil passage 30. The oil passage 30 has a first section 31, a second section 32, and a third section 33. The front end of the first section 31 is connected to the oil pipe 7, and its rear end is connected to the second section 32. The second section 32 is located between the first section 31 and the third section 33. That is, the second section 32 is located in the middle section of the oil passage 30. The third section 33 extends downward from the lower end of the second section 32. The third section 33 has an oil discharge port 35 that is open into the case 15. In this way, the oil passage 30 communicates the inside and outside of the case 15. As a result, the oil 70 in the oil pipe 7 is supplied into the case 15 from the oil discharge port 35.

[0028] In this embodiment of the motor 10, the oil 70 from the oil piping 7 outside the case 15 is directly supplied to the oil passage 30 of the terminal unit 20. Therefore, by supplying the terminal unit 20 with low-temperature oil 70, the terminal unit 20 can be stably cooled. Furthermore, the end of the oil passage 30 is open to the stator coil 18 as an oil discharge port 35. Therefore, the oil 70 that has passed through the oil passage 30 is discharged toward the stator coil 18, further cooling the stator coil 18.

[0029] Furthermore, as shown in Figure 3, in the second section 32, the height of the oil passage 30 is higher than the height of the other sections 31 and 33. Here, the height of the oil passage 30 refers to the upward direction in a cross-section perpendicular to the oil supply direction (i.e., the upward direction in the plane of Figure 3 in the first section 31, and the rightward direction in the plane of Figure 3 in the second section 32 and the third section 33). Furthermore, as shown in Figure 4, in the second section 32, the width of the oil passage 30 (i.e., the length in the left-right direction in the plane of Figure 4) is greater than the width of the other sections 31 and 33.

[0030] Therefore, the cross-sectional area of ​​the second section 32 is larger than that of the other sections 31 and 33. In this way, an oil reservoir with a locally enlarged cross-sectional area is formed in the second section 32.

[0031] Furthermore, the height of the second section 32 is higher than the height of the third section 33. Therefore, the distance between the rear end of the second section 32 and the first busbar 24 is shorter than the distance between the other sections 31 and 33 and the first busbar 24. In other words, the oil reservoir provided in the second section 32 is closer to the first busbar 24 compared to the other sections 31 and 33.

[0032] In this way, by forming an oil reservoir in the second section 32 of the oil passage 30, the amount of oil 70 stored in the main body 22 of the terminal unit 20 is increased, and the first busbar 24, which is a heat source, can be brought closer to the oil passage 30. As a result, the terminal unit 20 can be cooled more efficiently.

[0033] (Second example) The motor 10 of the second embodiment will be described with reference to Figures 5 and 6. The terminal unit 20 of the motor 10 of the second embodiment has an oil passage 90 instead of the oil passage 30 of the first embodiment. However, it has the same configuration in other respects.

[0034] In the second embodiment, no oil reservoir is formed in the oil passage 90. The oil passage 90 has a supply passage 91 connected to the oil piping 7, a labyrinth passage 92, and a discharge passage 93 whose end is open into the case 15. The discharge passage 93 has an oil outlet 95 that is open toward the stator coil 18.

[0035] As shown in Figure 6, the labyrinth channel 92 causes the oil 70 to meander. In other words, the labyrinth channel 92 increases the distance over which the oil 70 flows within the main body 22 of the terminal unit 20. This allows the terminal unit 20 to be cooled efficiently without increasing the amount of oil 70.

[0036] The specific examples of the technology disclosed herein have been described in detail above, but these are merely illustrative and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes to the specific examples illustrated above. Modifications of the above embodiments are listed below.

[0037] (Modification 1) The end of the oil passage 30 in the first embodiment does not have to be opened toward the stator coil 18 as an oil discharge port 35. For example, the oil discharge port 35 may be opened toward the stator core 17. That is, the terminal unit 20 does not have to be provided in a position facing the axial end of the stator 16, but may be provided facing the axial central part of the stator 16.

[0038] (Modification 2) The oil passage 90 of the second embodiment does not have to have a labyrinth passage 92. In that case, the oil passage 90 may have a supply passage that is connected to the oil pipe 7 and extends in the front-rear direction, and a discharge passage that extends downward from the rear end of the supply passage.

[0039] (Modification 3) Multiple oil passages may be formed in the main body 22 of the terminal unit 20.

[0040] (Modification 4) The motor 10 may be equipped with multiple terminal units 20.

[0041] The technical elements described herein or in the drawings demonstrate technical usefulness individually or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technologies illustrated herein or in the drawings can achieve multiple objectives simultaneously, and achieving even one of these objectives constitutes technical usefulness in itself. [Explanation of Symbols]

[0042] 2: Radiator, 3: Water piping, 4: Water pump, 6: Oil cooler, 7: Oil piping, 8: Oil pump, 10: Motor, 11: Shaft, 12F, 12R: Bearings, 13: Rotor, 14: Permanent magnet, 15: Case, 15h: Opening, 16: Stator, 17: Stator core, 18: Stator coil, 19: First connecting member, 20: Terminal unit, 22: Main body, 24: First busbar, 26: Seal, 30, 90: Oil passage, 31: First section, 32: Second section, 33: Third section, 35, 95: Oil outlet, 40: Power line, 42: Second busbar, 44: Second connecting member, 70, 72: Oil, 91: Supply passage, 92: Labyrinth passage, 93: Discharge passage, 100: Motor system

Claims

1. The case and, A stator, which is fixed inside the aforementioned case and has a stator coil, The rotor is rotatably supported within the aforementioned case and is opposed to the stator, A terminal unit provided in an opening formed in the case, Equipped with, The aforementioned terminal unit is A main body fixed to the aforementioned opening and composed of at least a portion of an insulating material, It is held by the main body, extends both inside and outside the case, and has an external connection terminal that is electrically connected to the stator coil within the case, It has, An oil passage is provided inside the main body of the terminal unit, which passes through the opening and connects the inside and outside of the case, and is configured to supply oil from outside the case into the case. Motor.

2. The motor according to claim 1, wherein the oil passage has an oil discharge port that is open towards the stator coil within the case.

3. In the intermediate section of the aforementioned oil passage, an oil reservoir is formed with a locally enlarged cross-sectional area. The motor according to claim 1, wherein the oil reservoir is located closer to the external connection terminal than other sections of the oil passage.

4. The motor according to claim 1, wherein a labyrinth channel is formed in the intermediate section of the oil channel, which meanders with respect to the longitudinal direction of the external connection terminal.

5. A motor according to any one of claims 1 to 4, An oil supply device connected to the oil passage outside the case and supplying oil to the oil passage, A motor system equipped with the following features.

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