JP2020070751A - Electric supercharger - Google Patents

Abstract

To provide an electric supercharger capable of reducing the adhesion amount of lubrication oil onto a rotary shaft.SOLUTION: A housing 11 of an electric supercharger 10 includes an oil passage 36 formed in the housing 11, a first supply path 41 communicating the oil passage 36 with a motor chamber S and extending to a first coil end 25a, and a second supply path 42 communicating the oil passage 36 with the motor chamber S and extending to a second oil end 25b. The first supply path 41 and the second supply path 42 linearly connect inlets 41a, 42a opened to the side of the oil passage 36 to outlets 41b, 42b opened to the side of the motor chamber S, respectively. In the first supply path 41, the outlet 41b is located nearer a stator core 26 than the inlet 41a in the axial direction of a rotary shaft 20. In the second supply path 42, the outlet 42b is located nearer the stator core 26 than the inlet 42a in the axial direction of the rotary shaft 20.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electric supercharger.

  For example, as described in Patent Document 1, an electric supercharger includes a rotating shaft, an electric motor that rotates the rotating shaft, an impeller that is coupled to an axial end of the rotating shaft, and an electric motor. And a housing having a motor chamber. The electric motor includes a tubular stator around which a coil is wound. The stator has a stator core and a coil end that is a part of the coil and that protrudes from the end of the stator core in the axial direction of the rotating shaft.

  By the way, the coil of the electric motor is apt to generate heat and reach a high temperature, and therefore needs to be cooled with lubricating oil. For this reason, the housing of the electric supercharger of Patent Document 1 has an oil passage, an oil inlet for communicating the oil passage with the outside of the housing, and a supply passage for communicating the oil passage with the motor chamber. The supply passage extends linearly from the oil passage toward the coil end along the radial direction of the rotating shaft. Then, the lubricating oil introduced into the oil passage from the oil introduction port is supplied to the coil end via the supply passage, whereby the coil is cooled.

JP, 2018-91301, A

  In such an electric supercharger, when the lubricating oil is supplied to the coil end via the supply passage, the lubricating oil flowing down from the coil end may adhere to the rotating shaft. The lubricating oil that adheres to the rotating shaft becomes a resistance against the rotation of the rotating shaft.

  The present invention has been made to solve the above problems, and an object thereof is to provide an electric supercharger that can reduce the amount of lubricating oil attached to a rotating shaft.

  An electric supercharger for solving the above problems accommodates a rotating shaft, an electric motor for rotating the rotating shaft, an impeller connected to an axial end of the rotating shaft, and the electric motor. A housing having a motor chamber, the electric motor includes a stator to which a coil is attached, the stator is a stator core, and an end of the stator core that is a part of the coil and in the axial direction of the rotating shaft. Has a coil end projecting from the housing, and the housing includes an oil passage formed in the housing, a communication passage communicating the oil passage with the outside of the housing, the oil passage and the motor chamber. A passage that communicates with each other and extends toward the coil end, and has an inlet opening to the oil passage side and an outlet opening to the motor chamber side. Line to knot, and the outlet than the inlet in the axial direction of the rotary shaft is summarized in that comprising an inclined supply passage located close to the stator core.

  According to this, the lubricating oil introduced into the oil passage through the communication passage and flowing through the oil passage is supplied to the coil end through the inclined supply passage. The inclined supply path is inclined so that the outlet is located closer to the stator core than the inlet in the axial direction of the rotating shaft. Therefore, the lubricating oil supplied from the inclined supply path to the coil ends easily flows to the stator core side in the axial direction of the rotating shaft. Therefore, it is possible to reduce the amount of the lubricating oil attached to the portion of the rotary shaft protruding from the coil end.

Further, in the electric supercharger, it is preferable that a virtual supply path obtained by virtually extending the inclined supply path in a direction in which the inclined supply path extends passes inside an inner peripheral surface forming the communication path.
According to this, the inclined supply passage is formed by processing a hole in the housing with a drill inserted into the oil passage through the communication passage. That is, the inclined supply path can be formed from the outside of the housing. In this case, for example, as compared with the case where a hole is formed in the housing to form the inclined supply path by a drill inserted into the housing from the opening of the housing for accommodating the electric motor, the inclined supply path is formed. Workability at the time of forming is improved.

  Further, in the electric supercharger, the housing has a wall portion that forms the motor chamber and has an opening portion that opens in an axial direction of the rotation shaft, and extends the inclined supply path of the inclined supply path. It is preferable that the virtual supply path that virtually extends in the direction passes inside the inner peripheral surface forming the opening.

  For example, when a hole is formed in the motor housing by a drill inserted into the oil passage through the communication passage to form the inclined supply passage, the position and size of the communication passage may be changed to determine the position of the inclined supply passage that can be formed. The angle is limited. On the other hand, when the virtual supply path passes inside the inner peripheral surface forming the opening, the inclined supply path is formed by processing a hole in the motor housing with a drill inserted into the motor housing through the opening. To be done. In this case, since the communication passage is not used, the degree of freedom in position and angle of the inclined supply passage is increased.

  According to the present invention, it is possible to reduce the amount of lubricating oil attached to the rotating shaft.

Sectional drawing of the electric supercharger of 1st Embodiment. Sectional drawing of the electric supercharger of 2nd Embodiment. Sectional drawing which shows another example of an electric supercharger. Sectional drawing which shows another example of an electric supercharger.

(First embodiment)
A first embodiment of the electric supercharger will be described below with reference to FIG. The electric supercharger of the present embodiment is installed in the engine room of an automobile and is used for compressing and supplying air as a fluid to the engine.

  As shown in FIG. 1, the housing 11 of the electric supercharger 10 includes a bottomed cylindrical motor housing 12 having a disk-shaped bottom wall 12a and a peripheral wall 12b extending from the bottom wall 12a in a cylindrical shape. Prepare The housing 11 includes a disk-shaped first plate 13 connected to the outer surface of the bottom wall 12a of the motor housing 12, and a disk-shaped second plate connected to the opening 12c of the peripheral wall 12b of the motor housing 12. 14 and a cover 14a attached to the second plate 14. Further, the housing 11 includes a compressor housing 15 connected to the first plate 13 on the side opposite to the motor housing 12. The motor housing 12, the first plate 13, the second plate 14, the cover 14a, and the compressor housing 15 are made of aluminum, for example.

  A first through hole 12h is formed in the bottom wall 12a of the motor housing 12. A cylindrical first bearing case 16 is attached to the first through hole 12h. The first bearing case 16 is made of iron. An annular engagement portion 16 a projects from the inner peripheral surface of the first bearing case 16.

  A second through hole 14h is formed in the second plate 14. A cylindrical second bearing case 17 is attached to the second through hole 14h. The second bearing case 17 is made of iron. The cover 14a closes the opening of the second through hole 14h on the side opposite to the motor housing 12.

  The electric supercharger 10 includes a rotating shaft 20 rotatably supported by the housing 11. The rotating shaft 20 passes from the inside of the second bearing case 17 through the inside of the motor housing 12 and the inside of the first bearing case 16, and penetrates through the first plate 13 to project into the compressor housing 15. A seal member 13a having a labyrinth seal is interposed between the rotary shaft 20 and the first plate 13. An impeller 21 is connected to one end of the rotary shaft 20 on the side projecting into the compressor housing 15.

  An electric motor 22 that rotates the rotating shaft 20 is housed in the motor housing 12. The electric motor 22 is housed in a motor chamber S that is a space surrounded by the bottom plate 12 a and the peripheral wall 12 b of the motor housing 12 and the second plate 14. That is, the bottom wall 12a and the peripheral wall 12b of the motor housing 12 and the second plate 14 are wall portions that form the motor chamber S.

  The electric motor 22 includes a tubular stator 23 and a rotor 24 arranged inside the stator 23. A coil 25 is wound around the stator 23. The rotor 24 rotates integrally with the rotating shaft 20 by supplying a current to the coil 25. The stator 23 is a stator core 26 fixed to the inner peripheral surface of the peripheral wall 12b of the motor housing 12, and a first coil end that protrudes from one axial end of the stator core 26, which is one end surface 26a that is close to the impeller 21. It has a first coil end 25a and a second coil end 25b as a coil end protruding from the other end surface 26b as an end near the second bearing case 17. Each of the first coil end 25a and the second coil end 25b is a part of the coil 25. One end of the rotary shaft 20 in the axial direction projects from the first coil end 25a, and the other end of the rotary shaft 20 in the axial direction projects from the second coil end 25b.

  The electric supercharger 10 includes a first bearing 31 that rotatably supports a portion of the rotary shaft 20 located between the impeller 21 and the electric motor 22 in the axial direction of the rotary shaft 20. The first bearing 31 is housed in the first bearing case 16. A plurality of first bearings 31 are provided between the first inner ring 31a fixed to the rotary shaft 20, the first outer ring 31b arranged outside the first inner ring 31a, and the first inner ring 31a and the first outer ring 31b. It has the 1st ball 31c arranged. The first inner ring 31a is press fitted into the rotary shaft 20. The first outer ring 31b is inserted inside the first bearing case 16.

  The electric supercharger 10 includes a second bearing 32 that rotatably supports the other end of the rotating shaft 20 in the axial direction. Therefore, the rotary shaft 20 is rotatably supported by the housing 11 via the first bearing 31 and the second bearing 32. The second bearing 32 is housed in the second bearing case 17, and is arranged at the end of the second bearing case 17 opposite to the cover 14 a in the axial direction of the rotary shaft 20. The second bearing 32 includes a second inner ring 32a fixed to the rotating shaft 20, a second outer ring 32b arranged outside the second inner ring 32a, and a plurality of second bearings 32 between the second inner ring 32a and the second outer ring 32b. It has the 2nd ball 32c arranged. The second inner ring 32a is press fitted into the rotary shaft 20. The second outer ring 32b is inserted inside the second bearing case 17.

  A storage chamber 33 is provided in the second bearing case 17 between the second bearing 32 and the cover 14a in the axial direction of the rotary shaft 20. An annular washer 34 and a preload spring 35 are accommodated in the accommodation chamber 33. One end of the preload spring 35 contacts the cover 14a, and the other end of the preload spring 35 contacts the end surface of the second outer ring 32b of the second bearing 32 via the washer 34. The preload spring 35 is arranged between the cover 14 a and the washer 34 while being compressed in the axial direction of the rotary shaft 20. Therefore, the cover 14 a holds the preload spring 35. Then, the preload spring 35 urges the second bearing 32 in the axial direction of the rotary shaft 20 by the force of returning to the original shape of the compressed preload spring 35.

  The compressor housing 15 includes a suction port 15a for sucking air (fresh air), an impeller chamber 15b communicating with the suction port 15a and accommodating an impeller 21, and a discharge chamber for discharging the air compressed by the impeller 21. 15 c, and a diffuser flow path 15 d that connects the impeller chamber 15 b and the discharge chamber 15 c.

  When the electric motor 22 is driven to rotate the rotating shaft 20, the impeller 21 rotates, and the centrifugal force of the rotating impeller 21 imparts velocity energy to the air sucked from the suction port 15a. The air that has been given a velocity energy and has a high velocity is decelerated in the diffuser flow passage 15d provided at the outlet of the impeller 21, and the velocity energy of the air is converted into pressure energy. Then, the high-pressure air is discharged from the discharge chamber 15c and supplied to an engine (not shown).

  An oil passage 36 extending in the axial direction of the rotary shaft 20 is formed in a portion of the housing 11 located above the motor chamber S in the direction of gravity. That is, the oil passage 36 is formed in the housing 11. The oil passage 36 is formed by closing the hole 36a formed in the peripheral wall 12b and opening to the bottom wall 12a side with the first plate 13. In addition, an oil introduction port 37 and a processing hole 38 are formed in a portion of the housing 11 located above the motor chamber S in the direction of gravity as a communication passage that connects the outside of the housing 11 and the oil passage 36. .. The oil introduction port 37 and the processing hole 38 respectively pass through a portion of the peripheral wall 12b located above the oil passage 36 in the gravity direction. That is, the oil introduction port 37 and the processing hole 38 are located above the oil passage 36 in the gravity direction. The oil introduction port 37 and the processed hole 38 are formed by processing a hole in the peripheral wall 12b from the outside of the housing 11 with a drill. In the axial direction of the rotary shaft 20, the oil introduction port 37 is located near the first bearing 31, and the processed hole 38 is located near the second bearing 32.

  A first mounting hole 39 and a second mounting hole 40 that connect the oil passage 36 and the motor chamber S are formed in a portion of the housing 11 that is located above the motor chamber S in the direction of gravity. Each of the first mounting hole 39 and the second mounting hole 40 penetrates a portion of the peripheral wall 12b located below the oil passage 36 in the gravity direction. In the axial direction of the rotary shaft 20, the first mounting hole 39 is located closer to the first bearing 31 and the second mounting hole 40 is located closer to the second bearing 32. In the present embodiment, the first mounting hole 39 overlaps the oil introduction port 37 and the rotary shaft 20 in the axial direction and the circumferential direction, and the second mounting hole 40 in the machining hole 38 and the rotary shaft 20 in the axial direction and the circumferential direction. overlapping. That is, the first mounting hole 39 is located below the oil introduction port 37 and the oil passage 36 in the gravity direction, and the second mounting hole 40 is located below the processing hole 38 and the oil passage 36 in the gravity direction. .. The first mounting hole 39 is formed by processing a hole from the outer peripheral side of the peripheral wall 12b to the peripheral wall 12b with a drill inserted into the oil passage 36 through the oil introduction port 37. The second mounting hole 40 is formed by processing a hole in the peripheral wall 12b from the outer peripheral side of the peripheral wall 12b with a drill inserted into the oil passage 36 through the processed hole 38.

  At a portion of the housing 11 located above the motor chamber S in the direction of gravity, the oil passage 36 and the motor chamber S are communicated with each other, and the first supply passage 41 is provided as an inclined supply passage extending toward the first coil end 25a. Are formed. In addition, at a portion of the housing 11 located above the motor chamber S in the direction of gravity, the second supply as an inclined supply passage that connects the oil passage 36 and the motor chamber S and extends toward the second coil end 25b. A passage 42 is formed. Each of the first supply passage 41 and the second supply passage 42 penetrates a portion of the peripheral wall 12b located below the oil passage 36 in the gravity direction. That is, each of the first supply passage 41 and the second supply passage 42 is located below the oil passage 36 in the gravity direction. The first supply passage 41 and the second supply passage 42 are arranged between the first attachment hole 39 and the second attachment hole 40 in the axial direction of the rotary shaft 20. The first supply path 41 is located near the first mounting hole 39, and the second supply path 42 is located near the second mounting hole 40.

  The first supply passage 41 has an inlet 41a that opens toward the oil passage 36 and an outlet 41b that opens toward the motor chamber S. The first supply path 41 linearly connects the inlet 41a and the outlet 41b. The first supply path 41 is arranged at a position overlapping the first coil end 25a in the axial direction of the rotary shaft 20. That is, the first supply path 41 is located above the first coil end 25a in the direction of gravity, and the outlet 41b faces the first coil end 25a. In the first supply path 41, the outlet 41b is located closer to the stator core 26 than the inlet 41a in the axial direction of the rotating shaft 20. Therefore, when viewed from a direction orthogonal to both the gravity direction and the axial direction of the rotary shaft 20, the first supply path 41 is inclined. The first supply passage 41 is formed by processing a hole in the peripheral wall 12b from the outer peripheral side of the peripheral wall 12b with a drill inserted into the oil passage 36 through the oil introduction port 37. For this reason, the first virtual supply path R1 as a virtual supply path obtained by virtually extending the first supply path 41 in the direction in which the first supply path 41 extends passes inside the inner peripheral surface forming the oil introduction port 37. ..

  The second supply passage 42 has an inlet 42a that opens toward the oil passage 36 and an outlet 42b that opens toward the motor chamber S. The second supply path 42 linearly connects the inlet 42a and the outlet 42b. The second supply path 42 is arranged at a position overlapping the second coil end 25b in the axial direction of the rotary shaft 20. That is, the second supply path 42 is located above the second coil end 25b in the direction of gravity, and the outlet 42b faces the second coil end 25b. In the second supply path 42, the outlet 42b is located closer to the stator core 26 than the inlet 42a in the axial direction of the rotating shaft 20. Therefore, when viewed from a direction orthogonal to both the gravity direction and the axial direction of the rotary shaft 20, the second supply passage 42 is inclined. The second supply path 42 is formed by processing a hole in the peripheral wall 12b from the outer peripheral side of the peripheral wall 12b with a drill inserted into the oil passage 36 through the processed hole 38. Therefore, the second virtual supply path R2, which is a virtual supply path obtained by virtually extending the second supply path 42 in the direction in which the second supply path 42 extends, passes inside the inner peripheral surface forming the processing hole 38.

  A discharge port 43 that connects the motor chamber S and the outside of the housing 11 is formed in a portion of the housing 11 that is located below the motor chamber S in the direction of gravity. The discharge port 43 penetrates a portion of the peripheral wall 12b located below the motor chamber S in the direction of gravity.

  A tubular first oil supply member 51 is attached to the first attachment hole 39 of the motor housing 12. The first oil supply member 51 is attached to the first attachment hole 39 before the electric motor 22 is housed in the motor housing 12 through the opening 12c. In the motor chamber S, the first oil supply member 51 projects from the inner surface of the peripheral wall 12b toward the rotary shaft 20. The first oil supply member 51 extends in the radial direction of the rotary shaft 20. The first oil supply member 51 is arranged between the electric motor 22 and the bottom wall 12 a of the motor housing 12 in the axial direction of the rotary shaft 20.

  A third supply path 53 is formed by the inner peripheral surface of the first oil supply member 51. The third supply passage 53 communicates with the oil passage 36 and also communicates with the first passage portion 53 a that extends downward in the direction of gravity and the first bearing portion 31 a in the axial direction of the rotating shaft 20. And a second passage portion 53b extending toward. An end of the second passage portion 53b opposite to the first passage portion 53a faces a part of the first bearing 31 between the first inner ring 31a and the first outer ring 31b. The flow passage cross-sectional area of the second passage portion 53b is smaller than the flow passage cross-sectional area of the first passage portion 53a.

  A tubular second oil supply member 52 is attached to the second attachment hole 40 of the motor housing 12. The second oil supply member 52 is attached to the second attachment hole 40 after the electric motor 22 is housed in the motor housing 12. In the motor chamber S, the second oil supply member 52 projects from the inner surface of the peripheral wall 12b toward the rotary shaft 20. The second oil supply member 52 extends in the radial direction of the rotary shaft 20. The second oil supply member 52 is arranged between the electric motor 22 and the second plate 14 in the axial direction of the rotary shaft 20.

  A fourth supply path 54 is formed by the inner peripheral surface of the second oil supply member 52. The fourth supply passage 54 communicates with the oil passage 36 and also communicates with the first passage portion 54 a that extends downward in the direction of gravity and the second passage 32 in the axial direction of the rotary shaft 20. And a second passage portion 54b extending toward. An end portion of the second passage portion 54b opposite to the first passage portion 54a faces a part of the second bearing 32 between the second inner ring 32a and the second outer ring 32b. The flow passage cross-sectional area of the second passage portion 54b is smaller than the flow passage cross-sectional area of the first passage portion 54a.

  An oil supply portion 55 is attached to the oil inlet 37 of the motor housing 12. Lubricating oil for cooling the coil 25, the first bearing 31, and the second bearing 32 of the electric motor 22 is introduced into the oil passage 36 from the supply hole 55a included in the oil supply unit 55. Further, a plug 56 is fitted in the processed hole 38 of the motor housing 12. The plug 56 is fitted into the processed hole 38 after the second attachment hole 40 and the second supply passage 42 are formed through the processed hole 38. As a result, the lubricating oil flowing through the oil passage 36 does not flow out of the housing 11 through the processed hole 38.

Next, the operation of the first embodiment will be described.
Lubricating oil for cooling the coil 25, the first bearing 31, and the second bearing 32 of the electric motor 22 is introduced into the oil passage 36 from the supply hole 55a of the oil supply portion 55 fitted in the oil introduction port 37. , Through the oil passage 36. Part of the lubricating oil flowing through the oil passage 36 flows into the first passage portion 53a of the first oil supply member 51, passes through the first passage portion 53a, and then from the second passage portion 53b to the first inner ring 31a and the first inner ring 31a. It is jetted toward the first outer ring 31b. At this time, since the flow passage cross-sectional area of the second passage portion 53b is smaller than the flow passage cross-sectional area of the first passage portion 53a, the lubricating oil flows from the second passage portion 53b to the first inner ring 31a and the first outer ring 31b. It is ejected vigorously between and. As a result, lubricating oil is supplied between the first inner ring 31a and the first outer ring 31b, slidability between the first inner ring 31a and each first ball 31c, and the first outer ring 31b and each first ball. Sliding property with 31c becomes good, and the first bearing 31 is cooled.

  Further, a part of the lubricating oil flowing through the oil passage 36 flows into the first passage portion 54a of the second oil supply member 52, passes through the first passage portion 54a, and then from the second passage portion 54b to the second inner ring 32a. And is jetted toward between the second outer ring 32b. At this time, since the flow passage cross-sectional area of the second passage portion 54b is smaller than the flow passage cross-sectional area of the first passage portion 54a, the lubricating oil flows from the second passage portion 54b to the second inner ring 32a and the second outer ring 32b. It is ejected vigorously between and. Thereby, lubricating oil is supplied between the second inner ring 32a and the second outer ring 32b, slidability between the second inner ring 32a and each second ball 32c, and the second outer ring 32b and each second ball. The slidability between the second bearing 32 and 32c is improved, and the second bearing 32 is cooled.

  Further, a part of the lubricating oil flowing through the oil passage 36 flows into the motor chamber S via the first supply passage 41 and is supplied to the first coil end 25a. The lubricating oil supplied to the first coil end 25a flows downward along the outer peripheral portion of the first coil end 25a in the gravity direction. As a result, the entire first coil end 25a is cooled by the lubricating oil, and the coil 25 of the electric motor 22 is cooled. At this time, in the first supply path 41, the outlet 41b is located closer to the stator core 26 than the inlet 41a in the axial direction of the rotating shaft 20. Therefore, the lubricating oil supplied to the first coil end 25a via the first supply passage 41 easily flows to the stator core 26 side in the axial direction of the rotating shaft 20. Therefore, the amount of lubricating oil attached to the portion of the rotary shaft 20 protruding from the first coil end 25a is reduced.

  Similarly, a part of the lubricating oil flowing through the oil passage 36 flows into the motor chamber S via the second supply passage 42 and is supplied to the second coil end 25b. The lubricating oil supplied to the second coil end 25b flows downward along the outer peripheral portion of the second coil end 25b in the gravity direction. As a result, the entire second coil end 25b is cooled by the lubricating oil, and the coil 25 of the electric motor 22 is cooled. At this time, in the second supply path 42, the outlet 42b is located closer to the stator core 26 than the inlet 42a in the axial direction of the rotating shaft 20. Therefore, the lubricating oil supplied to the second coil end 25b via the second supply path 42 easily flows to the stator core 26 side in the axial direction of the rotating shaft 20. Therefore, the amount of lubricating oil attached to the portion of the rotary shaft 20 protruding from the second coil end 25b is reduced.

Next, the effect of the first embodiment will be described.
(1) The motor housing 12 includes the first supply passage 41 for supplying the lubricating oil, which is introduced into the oil passage 36 through the oil introduction port 37 and flows through the oil passage 36, to the first coil end 25a. The first supply passage 41 is a passage that linearly connects the inlet 41a and the outlet 41b, and the outlet 41b is located closer to the stator core 26 than the inlet 41a in the axial direction of the rotating shaft 20. Therefore, the lubricating oil supplied to the first coil end 25a via the first supply passage 41 easily flows to the stator core 26 side in the axial direction of the rotating shaft 20. Therefore, it is possible to reduce the adhesion amount of the lubricating oil to the portion of the rotating shaft 20 protruding from the first coil end 25a.

  The motor housing 12 also includes a second supply passage 42 for supplying the lubricating oil flowing through the oil passage 36 to the second coil end 25b. The second supply passage 42 is a passage that linearly connects the inlet 42 a and the outlet 42 b, and the outlet 42 b is located closer to the stator core 26 than the inlet 42 a in the axial direction of the rotating shaft 20. Therefore, the lubricating oil supplied from the second supply passage 42 to the second coil end 25b easily flows to the stator core 26 side in the axial direction of the rotating shaft 20. Therefore, it is possible to reduce the adhesion amount of the lubricating oil to the portion of the rotary shaft 20 protruding from the second coil end 25b.

  (2) The first supply passage 41 is formed by forming a hole in the peripheral wall 12b of the motor housing 12 with a drill inserted into the oil passage 36 through the oil introduction port 37. That is, the first supply path 41 is formed from the outside of the housing 11. For this reason, the first virtual supply path R1 obtained by virtually extending the first supply path 41 in the direction in which the first supply path 41 extends passes inside the inner peripheral surface forming the oil introduction port 37. When the first supply path 41 is formed from the outside of the housing 11 as described above, a hole is formed in the peripheral wall 12b by a drill inserted into the motor housing 12 from the opening 12c of the motor housing 12 to form the first supply path. Compared with the case of forming 41, the workability in forming the first supply path 41 is improved.

  In addition, when a hole is formed in the motor housing 12 by the drill inserted inside the motor housing 12 to form the second supply path 42, in order to form the inclined second supply path 42, the tip of the drill is used. Need to be directed toward the opening 12c side. However, since the bottom wall 12a is located on the side opposite to the opening 12c in the axial direction of the rotary shaft 20, the tip of the drill may not be directed toward the opening 12c. On the other hand, in the present embodiment, the second supply passage 42 is formed by forming a hole in the peripheral wall 12b of the motor housing 12 with a drill inserted into the oil passage 36 through the processed hole 38. That is, the second supply path 42 can be formed from the outside of the housing 11. Therefore, the inclined second supply passage 42 can be formed, and workability in forming the second supply passage 42 is improved. When the second supply path 42 is formed in the motor housing 12 through the processed hole 38, the second virtual supply path R2 extending the second supply path 42 in the extending direction of the second supply path 42 forms the processed hole 38. Pass inside from the inner peripheral surface.

(Second embodiment)
A second embodiment of the electric supercharger will be described below with reference to FIG. Note that the description of the same configuration as the first embodiment is omitted.

  As shown in FIG. 2, the housing 11 includes a cylindrical motor housing 12. The motor housing 12 has a first opening 12d as an opening that opens toward the impeller 21 side in the axial direction of the rotating shaft 20 and a second opening 12e that serves as an opening opposite to the first opening 12d. Have and. The housing 11 includes a disk-shaped first plate 13 that closes the first opening 12d of the motor housing 12, and a disk-shaped second plate 14 that closes the second opening 12e of the motor housing 12. The motor chamber S is a space surrounded by the motor housing 12, the first plate 13, and the second plate 14. That is, the motor housing 12, the first plate 13, and the second plate 14 are walls that form the motor chamber S. A housing portion 13h is formed on the surface of the first plate 13 opposite to the impeller 21. The cylindrical first bearing case 16 is housed in the housing portion 13h.

  In the second embodiment, the first supply passage 41 is formed by processing a hole in the motor housing 12 with a drill inserted into the motor housing 12 from the second opening 12e. Therefore, the first virtual supply path R1, which is a virtual extension of the first supply path 41 in the direction in which the first supply path 41 extends, passes inside the inner peripheral surface forming the second opening 12e. The second supply path 42 is formed by processing a hole in the motor housing 12 with a drill inserted into the motor housing 12 from the first opening 12d. Therefore, the second virtual supply path R2, which is obtained by virtually extending the second supply path 42 in the direction in which the second supply path 42 extends, passes inside the inner peripheral surface forming the first opening 12d.

In the second embodiment, the following effect can be obtained in addition to the same effect as the effect (1) of the first embodiment.
(3) When a hole is formed in the motor housing 12 by the drill inserted into the oil passage 36 through the oil inlet 37 to form the first supply passage 41, depending on the position and size of the oil inlet 37, The position and angle of the first supply path 41 that can be formed are limited. On the other hand, in the second embodiment, the first supply path 41 is formed by processing a hole in the motor housing 12 with a drill inserted into the motor housing 12 from the second opening 12e. In this case, since the oil introduction port 37 is not used, the degree of freedom of the position and angle of the first supply passage 41 is increased.

  Further, when the hole is formed in the motor housing 12 by the drill inserted into the oil passage 36 through the processed hole 38 to form the second supply path 42, it can be formed depending on the position and size of the processed hole 38. The position and angle of the second supply path 42 are limited. On the other hand, in the second embodiment, the second supply passage 42 is formed by processing a hole in the motor housing 12 with a drill inserted into the motor housing 12 through the first opening 12d. In this case, since the processed hole 38 is not used, the degree of freedom of the position and angle of the second supply passage 42 is increased.

  The first embodiment and the second embodiment can be modified and implemented as follows. The first embodiment, the second embodiment, and the modified example can be implemented in combination with each other within a technically consistent range.

In the first and second embodiments, only the first supply passage 41 may be formed in the housing 11, or only the second supply passage 42 may be formed.
In the first embodiment, only the first supply path 41 linearly connects the inlet 41a and the outlet 41b, and the outlet 41b is located closer to the stator core 26 than the inlet 41a in the axial direction of the rotating shaft 20. It may be an inclined supply path. Similarly, only the second supply passage 42 is an inclined supply passage in which the inlet 42a and the outlet 42b are linearly connected, and the outlet 42b is located closer to the stator core 26 than the inlet 42a in the axial direction of the rotating shaft 20. May be.

  In the second embodiment, the first supply passage 41 may extend linearly along the radial direction of the rotary shaft 20. Similarly, the second supply passage 42 may linearly extend along the radial direction of the rotary shaft 20.

  In the first embodiment, in the motor housing 12, the opening 12c is opened on the impeller 21 side in the axial direction of the rotary shaft 20, and the bottom wall 12a is located on the second bearing case 17 side in the axial direction of the rotary shaft 20. It may have a bottomed tubular shape.

  In the first embodiment, the second supply path 42 is formed by processing a hole in the motor housing 12 with a drill inserted inside the motor housing 12 from the first through hole 12h as an opening. Good. In this case, the second virtual supply path R2, which is a virtual extension of the second supply path 42 in the direction in which the second supply path 42 extends, passes inside the inner peripheral surface forming the first through hole 12h.

  In the first and second embodiments, the number of the first supply passages 41 formed in the motor housing 12 is not limited to one. Similarly, the number of the second supply passages 42 formed in the motor housing 12 is not limited to one.

  For example, as shown in FIG. 3, in the motor housing 12, a first supply passage 411 formed through the oil introduction port 37 and a first supply passage 412 formed through the opening 12c of the motor housing 12. The two first supply paths 41 may be formed.

In the first embodiment and the second embodiment, the configuration of the housing 11 may be changed to the configuration shown in FIG. 4, for example.
In FIG. 4, a recess 121 that is recessed toward the motor chamber S and that extends in the axial direction of the rotary shaft 20 is formed in a portion of the motor housing 12 that is located above the motor chamber S in the direction of gravity. A lid member 27 that closes the recess 121 is attached to the outer peripheral surface of the motor housing 12. The lid member 27 is a part of the housing 11. In the housing 11 having such a configuration, the space surrounded by the recess 121 and the lid member 27 serves as the oil passage 36. Therefore, the housing 11 is provided with the oil passage 36. The first mounting hole 39, the second mounting hole 40, the first supply passage 41, and the second supply passage 42 are formed on the bottom surface of the recess 121, and the oil introduction port 37 is formed on the lid member 27. The oil introduction port 37 is arranged between the first supply path 41 and the second supply path 42 in the axial direction of the rotating shaft 20. The lid member 27 is attached to the motor housing 12 after the first attachment hole 39, the second attachment hole 40, the first supply passage 41, and the second supply passage 42 are formed on the bottom surface of the recess 121.

In the first and second embodiments, the first bearing 31 and the second bearing 32 are not limited to rolling bearings in which rolling elements are balls, and may be, for example, roller bearings in which rolling elements are columnar. .
The technical idea that can be understood from the second embodiment and the above-described modification will be described.

  (A) a rotary shaft, an electric motor for rotating the rotary shaft, an impeller connected to an axial end of the rotary shaft, and a housing having a motor chamber for housing the electric motor, The electric motor includes a stator to which a coil is attached, and the stator has a stator core and a coil end that is a part of the coil and projects from an end of the stator core in the axial direction of the rotating shaft. The housing has an oil passage formed in the housing, a communication passage for communicating the oil passage with the outside of the housing, a communication passage for communicating the oil passage with the motor chamber, and a supply extending toward the coil end. A passage and a wall portion that forms the motor chamber and has an opening that opens in the axial direction of the rotating shaft, Virtual supply path that extends virtually in the direction of extension of the feed path, the electric supercharger, characterized in that through the inside from the inner peripheral surface forming the opening.

  DESCRIPTION OF SYMBOLS 10 ... Electric supercharger, 11 ... Housing, 12 ... Motor housing as a wall part, 12c ... Opening part, 12d ... 1st opening part as an opening part, 12e ... 2nd opening part as an opening part, 12h ... Opening First through hole as a part, 13 ... first plate as a wall part, 14 ... second plate as a wall part, 20 ... rotary shaft, 21 ... impeller, 22 ... electric motor, 23 ... stator, 25 ... coil, 25a ... 1st coil end as coil end, 25b ... 2nd coil end as coil end, 26 ... Stator core, 26a ... One end surface as end, 26b ... Other end surface as end, 36 ... Oil passage, 37 ... Oil introduction port as a passage, 38 ... Machining hole as a communication passage, 41 ... First supply passage as an inclined supply passage, 41a ... Inlet, 41b ... Outlet, 42 ... First as an inclined supply passage Supply passage 42a ... inlet, 42b ... outlet, a first virtual supply passage as R1 ... virtual supply passage, a second virtual supply path as R2 ... virtual supply path, S ... motor chamber.

Claims (3)

A rotation axis,
An electric motor for rotating the rotating shaft,
An impeller connected to the axial end of the rotating shaft,
A housing having a motor chamber that houses the electric motor;
Equipped with
The electric motor includes a stator to which a coil is attached,
The stator has a stator core and a coil end that is a part of the coil and that protrudes from an end of the stator core in the axial direction of the rotating shaft.
The housing is
An oil passage formed in the housing,
A communication passage communicating the oil passage and the outside of the housing;
A passage that connects the oil passage and the motor chamber and extends toward the coil end, and linearly connects an inlet opening to the oil passage side and an outlet opening to the motor chamber side, and the rotation. An inclined supply path in which the outlet is located closer to the stator core than the inlet in the axial direction of the shaft,
An electric supercharger comprising:   The electric supercharger according to claim 1, wherein a virtual supply path, which is formed by virtually extending the inclined supply path in a direction in which the inclined supply path extends, passes inside an inner peripheral surface forming the communication path. The housing has a wall portion that forms the motor chamber and has an opening that opens in the axial direction of the rotating shaft,
The electric supercharger according to claim 1, wherein a virtual supply path, which is formed by virtually extending the inclined supply path in a direction in which the inclined supply path extends, passes inside an inner peripheral surface forming the opening.