JP6663334B2 - Motor unit for vehicle - Google Patents

Description

  The present invention relates to a motor unit for a vehicle.

The motor unit for a vehicle includes a motor housing that houses a motor in which a rotor is rotatably housed inside a substantially annular stator, and a gear housing that houses a gear portion that transmits a driving force of the motor to wheels. It is common to have an integrated housing.
In this type of vehicle motor unit, a refrigerant is used to cool the motor. Particularly, when heat generation is remarkable, for example, under a high load, a part of the rotor is immersed in a cooling medium (cooling oil). The present applicant has already proposed a technique for increasing the cooling effect of the motor as described above (for example, see Patent Document 1).

  The technique of Patent Document 1 utilizes the fact that the normal oil level of the cooling oil stored in the motor housing rises rearward when the vehicle is accelerating or climbing a slope, so that it does not stay at a part of the rotor. In addition, the neutral point and even the middle dotted line are immersed in the cooling oil to promote cooling of these parts.

Japanese Patent No. 4866934

However, the technique of Patent Document 1 is effectively applied under the condition that the motor unit housing has a structure including an axially extending portion of the housing referred to as a “crossover housing” on both axial sides of the motor housing. Is done. That is, a raised bottom is formed on the rear side of the vehicle in the portion of the above "transition housing" by raising a part of an inner peripheral surface of a substantially cylindrical shape to a raised bottom. By utilizing the phenomenon that the oil level of the oil rises remarkably, the neutral point and the middle dotted line as well as a part of the rotor are immersed in the cooling oil for cooling.
Therefore, in the case of a compact motor unit having no “transition housing” portion in the housing, the technique of Patent Document 1 cannot be applied.

  The present invention has been made in view of the above-described situation, and has a compact housing and does not require a separate power unit or the like. It is an object of the present invention to provide a motor unit for a vehicle that can effectively cool the vehicle.

(1) A motor housing (for example, a motor housing 2 described later) that accommodates a motor (for example, a motor 10 described later) and the driving force of the motor is transmitted to an output shaft (for example, output shafts 101 and 102 described later). A gear housing (for example, a gear housing 3 described later) for housing a gear unit (for example, a gear unit 30 described later) is arranged in the axial direction of the motor and joined together to form a housing (for example, described later). A motor unit (e.g., a vehicle motor unit 1 to be described later) having a housing 100), which is formed so as to rise from a bottom inner surface near a joint of the gear housing and the motor housing. Cooling oil (for example, cooling oil) in the gear housing portion according to the vertical displacement of the front side of the vehicle A cooling oil level adjuster (for example, a cooling oil level adjuster 40 to be described later) having a volume exclusion body (for example, a volume exclusion body 400 to be described later) shaped to increase or decrease the degree of immersion in a cooling oil 60 (to be described later) is provided. , Motor units for vehicles.

  In the motor unit for a vehicle according to the above (1), when the cooling oil leans so that the front portion of the vehicle is relatively high when climbing a hill and the cooling oil is relatively deviated rearward, the volume exclusion body becomes larger. Due to the immersion, the level of the cooling oil rises corresponding to the decrease in the effective volume due to the immersed portion. Such a rise in the liquid level is equally generated in the motor housing portion opposite to the gear housing portion, where the cooling oil generated by the scooping of the cooling oil by the gear portion does not reach. Accordingly, as the level of the cooling oil rises, in the motor, the portion below the rotor core together with the stator core is immersed in the cooling oil over the entire length in the axial direction. Therefore, when the motor is in a high load state while the vehicle is traveling on an uphill road, the cooling effect of the cooling oil on the rotor core is remarkable over its entire length in the axial direction, and the motor is in a high load state. In this case, overheating of the motor is effectively suppressed. In this case, since the volume elimination body is provided on the gear housing portion side, there is no problem even when applied to a vehicle motor unit of a type having no space between the motor housing portion and the stator core.

(2) The vehicle motor unit according to the above (1), wherein the volume exclusion body has a shape in which the height increases from the front to the rear in the front-rear direction of the vehicle.

  In the vehicle motor unit of the above (2), in particular, in the vehicle motor unit of the above (1), when the vehicle is accelerated forward and the cooling oil is relatively biased rearward due to its inertia force, the volume elimination body is provided. Are immersed deeper into the cooling oil, which causes a rise in the level of the cooling oil corresponding to an increase in the volume displacement volume. When the liquid level of the cooling oil rises, the cooling effect of the cooling oil on the rotor core also becomes remarkable over its entire length in the axial direction, and even if the motor is under a high load, the overheating of the motor is effectively prevented. Is suppressed.

(3) The vehicle motor unit according to (1) or (2), wherein the volume elimination body is formed by a part of the gear housing portion.

  In the vehicle motor unit of the above (3), in the vehicle motor unit of the above (1) or (2), in particular, the shape of a part of the gear housing portion necessarily provided in this type of vehicle motor unit is changed to a volume eliminating body. Thus, the cooling oil level regulator can be simply configured without requiring other components, power means, sensors, and the like. Further, the vehicle motor unit can be downsized as a whole.

  ADVANTAGE OF THE INVENTION According to this invention, the motor for vehicles which can cool a motor effectively at the time of a high load, such as at the time of acceleration of a vehicle, a hill climbing, etc., without having a separate power means etc. while having a compact housing Units can be provided.

FIG. 3 is a skeleton diagram showing a driving force transmission system in the vehicle motor unit as one embodiment of the present invention. FIG. 2 is a schematic diagram showing an axial cross section of the vehicle motor unit of FIG. 1. FIG. 2 is a schematic diagram illustrating a cross section in a direction orthogonal to an axis of a cooling oil level adjuster of the vehicle motor unit in FIG. 1, and is a diagram illustrating a state where the vehicle is traveling on a flat road at a steady speed. FIG. 2 is a schematic diagram illustrating a cross section in a direction orthogonal to an axis of a cooling oil level adjuster of the vehicle motor unit in FIG. 1, and is a diagram illustrating a state where the vehicle is traveling on an uphill road. It is a schematic diagram which shows the cross section of the axial direction of the motor unit for vehicles relevant to this invention. It is a schematic diagram which shows the cross section of the axial direction of the vehicle motor unit as a modification of the vehicle motor unit of FIG. FIG. 7 is a schematic view showing a cross section in a direction orthogonal to an axis of a cooling oil level adjustment unit common to the vehicle motor units of FIGS. 5 and 6. FIG. It is a figure which pays attention to a structure. FIG. 7 is a schematic diagram illustrating a cross section in a direction orthogonal to an axis of a cooling oil level adjustment unit common to the vehicle motor units of FIGS. 5 and 6, and is a diagram illustrating a state where the vehicle is traveling on an uphill. FIG. 7 is a schematic diagram illustrating a cross section in a direction orthogonal to an axis of a cooling oil level adjustment unit common to the vehicle motor units of FIGS. 5 and 6. FIG. It is a figure which pays attention to a structure. FIG. 7 is a schematic diagram illustrating a cross section in a direction orthogonal to an axis of a cooling oil level adjustment unit common to the vehicle motor units of FIGS. 5 and 6, and is a diagram illustrating a state where the vehicle is traveling on a downhill. FIG. 7 is a schematic diagram illustrating a cross section in a direction orthogonal to an axis of a cooling oil level adjustment unit common to the vehicle motor units of FIGS. 5 and 6, in which the vehicle is traveling on a flat road at a steady speed. It is a figure showing how to cut a section. FIG. 12 is a sectional view taken along the line AA including the cooling oil level adjusting unit of FIG. 11. FIG. 13 is a diagram illustrating the motor of FIG. 12 excluding a rotor and a stator. FIG. 12 is a cross-sectional view taken along a line BB above a cooling oil level adjustment unit in FIG. 11.

Hereinafter, a vehicle motor unit as one embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a skeleton diagram showing a driving force transmission system in a vehicle motor unit as one embodiment of the present invention.
The motor unit 1 for a vehicle shown in FIG. 1 has a housing 100 in which a motor housing part 2 and a gear housing part 3 are joined side by side in the axial direction of the motor. The motor housing section 2 houses the motor 10. The gear housing unit 3 houses a gear unit 30 that transmits the driving force of the motor 10 to the output shafts 101 and 102.

The motor housing 2 includes a motor housing block 21 that surrounds the outer periphery of the motor 10 and a side housing block 22 that covers the side of the motor housing block 21 opposite to the gear housing 3 side.
The gear housing section 3 includes a gear housing block 31 surrounding the outer periphery of the gear section 30 and a housing block 32 covering a side surface of the gear housing block 31 opposite to the motor housing section 2 side.

The motor 10 has an annular stator core 11 and a rotor core 12 arranged such that its outer peripheral surface is closely opposed to the inner peripheral surface of the stator core 11. A coil 13 is wound around the stator core 11. The rotor core 12 has a hollow rotor shaft 14 having a common axis with the output shaft 101. The output gear 4 is provided at the end where the rotor shaft 14 extends inside the gear housing 3.
A large-diameter input gear 5 meshing with the output gear 4 is provided so as to rotate around the speed reducer shaft 6. A final drive gear 7 is provided at an end of the reduction gear shaft 6 that extends on the side opposite to the input gear 5. The final drive gear 7 meshes with the final driven gear 8 to rotationally drive a differential device 9 (its differential case).

That is, the driving force of the motor 10 is transmitted through the driving force transmission path of the motor 10 → the rotor shaft 14 → the output gear 4 → the input gear 5 → the reduction gear shaft 6 → the final drive gear 7 → the final driven gear 8 → the differential device 9. Is transmitted to The driving force of the motor 10 transmitted as described above is appropriately distributed to the output shafts 101 and 102 by the differential device 9 and output.
The gear section 30 includes the gear and the shaft in the driving force transmission path.

  In the motor unit 1 for a vehicle according to the present embodiment, the cooling oil level adjuster 40 is provided in the vicinity of the joint of the gear housing 3 and the motor housing 2 in particular. As will be described later, the cooling oil level adjuster 40 is formed so as to rise from the inner side of the bottom near the joint of the gear housing 3 with the motor housing 2, and the gear is adjusted in accordance with the vertical displacement on the front side of the vehicle. A volume exclusion body (described later) having a shape in which the degree of immersion in the cooling oil 60 in the housing portion 3 increases and decreases.

Next, with reference to FIGS. 2, 3 and 4, the arrangement of the cooling oil level adjuster 40 in the vehicle motor unit 1 and the configuration and operation of the cooling oil level adjuster 40 will be described.
FIG. 2 is a schematic diagram showing a cross section in the axial direction of the vehicle motor unit 1 showing the driving force transmission system in FIG.
FIG. 3 is a schematic diagram showing a cross section in a direction orthogonal to an axis of a cooling oil level adjuster of the vehicle motor unit in FIG. 1, and is a diagram showing a state where the vehicle is traveling on a flat road at a steady speed.
FIG. 4 is a schematic diagram showing a cross section in a direction orthogonal to the axis of the cooling oil level adjuster of the vehicle motor unit in FIG. 1, and is a diagram showing a state where the vehicle is traveling on an uphill road.
2, 3, and 4, parts corresponding to those in FIG. 1 are denoted by the same reference numerals.

  In FIG. 2, a stator core 11 is provided on the inner peripheral side of the motor housing block 21 of the motor housing portion 2 of the motor unit 1 for a vehicle so that its outer periphery is in contact with the stator core 11. A coil 13 is wound around the stator core 11. A rotor core 12 is provided such that its outer periphery is closely opposed to the inner peripheral surface of the stator core 11, and a magnet 12a is embedded in the rotor core 12 so as to face the outer periphery.

On the other hand, the gear portion 30 in the gear housing block 31 of the gear housing portion 3 includes a plurality of gears as described above with reference to FIG. 1, but in FIG. A relatively large-diameter gear (for example, the input gear 5 and the final driven gear 8 in FIG. 1) that mainly contributes to the above is symbolically represented as a large-diameter gear 5a. The large-diameter gear 5a is partially submerged below the liquid level 61 of the cooling oil 60.
A cooling oil level controller 40 is disposed on a bottom portion 33 of the gear housing portion 3 near a joint portion with the motor housing portion 2 with its own bottom portion 41 joined thereto. However, it is not essential that the cooling oil level adjuster 40 is arranged in a form in which the bottom 41 is joined to the bottom 33 of the gear housing 3.
In this embodiment, in particular, the cooling oil level adjuster 40 (the volume elimination body 400 described later) is formed as a part of the gear housing block 31 of the gear housing portion 3.

As can be easily understood with reference to FIG. 3, the cooling oil level controller 40 has a volume exclusion body 400 formed so as to rise from the bottom 41 toward the top 42, and the volume exclusion body in the present embodiment. In particular, the shape 400 increases in height from the front to the rear in the front-rear direction of the vehicle. This shape is a shape in which the degree of immersion in the cooling oil 60 in the gear housing portion 3 increases or decreases according to the vertical displacement of the front side of the vehicle. That is, when the front side of the vehicle is relatively high as on an uphill road, the degree to which the volume exclusion body 400 is immersed in the cooling oil 60 becomes relatively large.
In the present embodiment, the liquid level of the cooling oil level 61 is adjusted by utilizing the fact that the volume exclusion action changes according to the degree of immersion of the volume exclusion body 400 in the cooling oil 60 as described above. If the vehicle is on an uphill road or is moving forward while accelerating, the displacement of the displacement oil 400 is caused by the inclination of the displacement oil 400 with respect to the liquid surface 61 of the cooling oil 60 and the inertia force of the cooling oil 60. The volume of the part immersed in the cooling oil 60 increases. Therefore, as a result of the volume elimination body 400 excluding a relatively large amount of fluid (cooling oil 60), the liquid level 61 of the cooling oil rises.

The volume exclusion body 400 in the cooling oil level controller 40 has been outlined above, and will be described in more detail with reference to FIGS.
FIG. 3 shows a case where the vehicle is traveling on a flat road at a steady speed, and at this time, the level 61 of the cooling oil of the cooling oil 60 is substantially horizontal. In this state, the degree of volume exclusion (the volume excluding the cooling oil 60) due to the part where the volume exclusion body 400 is immersed in the cooling oil 60 is V0, and the level position of the liquid level 61 of the cooling oil is L0. I do.
In other words, when the volume in which the volume exclusion body 400 is immersed in the cooling oil 60 is V0, the level position of the liquid level 61 of the cooling oil is L0.

  As described above, when the level position of the liquid level 61 of the cooling oil 60 is L0, the stator core 11 of the motor 10 is immersed in the cooling oil 60, but the rotor core 12 is slightly lower than the liquid level 61 of the cooling oil 60. Located above and not immersed. Therefore, the rotor core 12 is not affected by the rotational resistance caused by being immersed in the cooling oil 60.

  On the other hand, as shown in FIG. 4, when the vehicle is traveling on an uphill road, the volume exclusion body 400 is immersed in the cooling oil 60 to a greater extent than in FIG. That is, in the present embodiment, since the volume elimination body 400 adopts a shape in which the height increases from the front part to the rear part in the front-rear direction of the vehicle, the front part of the vehicle becomes relatively high when climbing a hill. When the cooling oil 60 is tilted so as to be deflected relatively rearward due to its inertial force, the volume elimination body 400 is immersed in the cooling oil 60 to a greater extent, and the degree of volume elimination thereby (the cooling oil 60 is eliminated). 3) is larger than V0 in the case of FIG.

For this reason, the level position of the liquid level 61 of the cooling oil 60 rises from L0 to L1 according to the difference between the volume excluded volumes V0 and V1, and the motor 10 and the stator core 11 and the lower part of the rotor core 12 Is also immersed in the cooling oil 60. The rise (L1-L0) of the level position of the liquid surface 61 occurs equally in the axial direction of the motor 10 unless the vehicle is inclined in the left-right direction. In other words, the level position of the liquid surface 61 of the cooling oil 60 also rises equally at the part of the motor 10 on the side of the side housing block 22 where the splash of the cooling oil 60 lifted up by the large-diameter gear 5a does not reach. The lower part of 12 is immersed in the cooling oil 60.
Therefore, when the vehicle is traveling on an uphill road and the motor 10 is in a high load state, the cooling effect of the cooling oil 60 on the rotor core 12 is also remarkable over its entire length in the axial direction, and the motor 10 Even in a high load state, overheating of the motor 10 is effectively suppressed.

  In addition, even when the vehicle is moving forward while accelerating on a flat road, a change in the level position of the liquid level 61 of the cooling oil 60 exhibits a phenomenon similar to that in the case where the vehicle is traveling on an uphill road. That is, when the vehicle is moving forward while accelerating on a flat road, the cooling oil 60 is biased to the rear of the vehicle due to its own inertia. Therefore, the volume exclusion body 400 is immersed in the cooling oil 60 to a greater extent, thereby increasing the degree of volume exclusion. Therefore, the same phenomenon as when traveling on an uphill road occurs, and the level position of the liquid level 61 of the cooling oil 60 rises from L0 to L1 described above. As a result, when the vehicle moves forward while accelerating and the motor 10 is in a high load state, the portion below the rotor core 12 is immersed in the cooling oil 60, and the overheating of the motor 10 is effectively suppressed.

Further, in the present embodiment, the volume exclusion body 400 in the cooling oil level controller 40 is formed by a part of the gear housing block 31 of the gear housing unit 3. For this reason, in this kind of vehicle motor unit 1, only the shape of a part of the gear housing block 31 of the gear housing part 3 necessarily provided is like the volume exclusion body 400, and other components, power means or sensors The cooling oil level adjuster 40 can be simply configured without the need for any other operations. Further, the vehicle motor unit 1 can be downsized as a whole.
Further, in the present embodiment, since the above-described volume elimination body 400 is provided in the gear housing portion 3, there is no space between the motor housing portion and the stator core for a vehicle motor unit (for example, a motor housing portion). There is no problem in application to the type in which the stator core is shrink-fitted).

Next, a vehicle motor unit related to the present invention will be described.
FIG. 5 is a schematic view showing a cross section in the axial direction of a motor unit for a vehicle related to the present invention.
FIG. 6 is a schematic diagram showing an axial cross section of the vehicle motor unit of FIG.
5 and 6, the form of the driving force transmission system is the same as that described above with reference to FIG. Further, the mechanical configuration has many parts in common with the vehicle motor unit described above with reference to FIG.
Therefore, in FIG. 5 and FIG. 6, the same reference numerals are given to the corresponding parts in FIG. 1 and FIG.

The motor unit 1a for a vehicle shown in FIG. 5 has a housing 100a in which a motor housing part 2 and a gear housing part 3 are joined together side by side in the axial direction of the motor. The motor housing section 2 houses the motor 10. The gear housing unit 3 houses a gear unit 30 that transmits the driving force of the motor 10 to the output shafts 101 and 102 (see FIG. 1).
The stator core 11 is provided on the inner peripheral side of the motor housing block 21 of the motor housing section 2 of the motor unit 1a for the vehicle such that the outer periphery of the stator core 11 is opposed to the inner peripheral side at a predetermined interval.

  In the present embodiment, the outer periphery of the stator core 11 is confined by a tubular stator holder 111 without any gap and is restrained, and is fixed in the motor housing block 21. More specifically, the stator holder 111 is fastened by a bolt 222 to a boss 221 projecting from the side housing block 22 to the inside in the axial direction of the motor 10 at a flange portion provided on the side housing block 22 side. As a result, the stator core 11 is fixed in the motor housing block 21.

As a result, a space is formed between the outer periphery of the stator core 11 and the inner surface of the motor housing block 21, and this space has a radial distance S <b> 5 in a portion between the outer periphery of the stator core 11 and the bottom 23 of the motor housing block 21.
In the motor unit for a vehicle, a cooling oil level adjusting unit 50 described later is formed in a space having the above-described space S5 between the outer periphery of the stator core 11 and the inner surface of the motor housing block 21.
The cooling oil level adjusting portion 50 is formed in a container shape so as to extend in the axial direction of the motor between the inner peripheral surface of the bottom portion 23 of the motor housing block 21 of the motor housing portion 2 and the outer peripheral surface of the stator core 11 of the motor 10. Have been. Such a cooling oil level adjusting unit 50 may be formed in a container shape so as to extend over at least a part of the gear housing unit 3 (the gear housing block 31).

  A coil 13 is wound around the stator core 11. A rotor core 12 is provided such that its outer periphery is closely opposed to the inner peripheral surface of the stator core 11, and a magnet 12a is embedded in the rotor core 12 so as to face the outer periphery.

  On the other hand, the gear portion 30 in the gear housing block 31 of the gear housing portion 3 includes a plurality of gears as described above with reference to FIG. 1, but in FIG. A relatively large-diameter gear (for example, the input gear 5 and the final driven gear 8 in FIG. 1) that mainly contributes to the above is symbolically represented as a large-diameter gear 5a. The large-diameter gear 5a is partially submerged below the liquid level 61 of the cooling oil 60.

Next, the vehicle motor unit 1b of FIG. 6 will be described. As described above, the vehicle motor unit 1b in FIG. 6 is a modified example of the vehicle motor unit 1a in FIG. 5. Therefore, in FIG. 6, the same parts as those in FIG. The description is omitted for each part.
The vehicle motor unit 1b in FIG. 6 differs from the vehicle motor unit 1a in FIG. 5 in that the stator core 11 is fixed in the motor housing block 21 using the stator holder 111 in the vehicle motor unit 1a. On the other hand, in the motor unit 1b for a vehicle, the stator core 11 is fixed in the motor housing block 21 without using such a stator holder 111.

  That is, in the motor unit 1b for a vehicle, the stator core 11a of the motor 10 is partially formed to have a diameter larger than that of the stator core 11 described above or a shape having a portion protruding in the radial direction. A plurality of through holes are provided in a portion facing the periphery so as to penetrate in the axial direction. The stator core 11a is fixed in the motor housing block 21 by being fastened to the boss 221 protruding from the side housing block 22 through a long bolt 222a through each of these through holes.

As a result, a space is formed between the outer periphery of the stator core 11a and the inner surface of the motor housing block 21, and this space has a radial interval S6 at a portion between the outer periphery of the stator core 11a and the bottom 23 of the motor housing block 21.
In the example of FIG. 6, similarly to the example of FIG. 5, a cooling oil level adjusting unit 50 described later is formed in a space having the above-described space S6 between the outer periphery of the stator core 11 and the inner surface of the motor housing block 21. Have been.

That is, the cooling oil level adjusting unit 50 is arranged between the inner peripheral surface of the bottom portion 23 of the motor housing block 21 of the motor housing unit 2 and the outer peripheral surface of the stator core 11 of the motor 10 in the axial direction of the motor. It is formed in a container shape so as to extend over at least a part of the housing block 31).
The remaining mechanical configuration of the vehicle motor unit 1b of FIG. 6 is substantially the same as that of the vehicle motor unit 1a of FIG.

Next, the cooling oil level adjusting unit 50 common to the vehicle motor units 1a and 1b shown in FIGS. 5 and 6 will be described with reference to FIGS.
Note that the vehicle motor units 1a and 1b shown in FIGS. 5 and 6 are arranged in the corresponding vehicle such that the axial direction of the motor 10 is substantially parallel to the left-right direction of the vehicle.
7 to 10 are schematic diagrams showing a cross section in a direction orthogonal to the axis of the cooling oil level adjusting unit (the rotor shaft 14 of the motor 10).
7 shows a state in which the vehicle is traveling on a flat road at a steady speed with a focus on the configuration of the rear volume, FIG. 8 shows a state in which the vehicle is traveling on an uphill road, and FIG. FIG. 10 is a diagram illustrating a state in which the vehicle is traveling on a flat road at a constant speed, paying attention to the configuration of the front volume portion, and FIG. 10 is a diagram illustrating a state in which the vehicle is traveling on a downhill road.
7 to 10, parts corresponding to those in FIGS. 5 and 6 are denoted by the same reference numerals.
The cooling oil level adjusting unit 50 fills a region including a space between the inner peripheral surface of the bottom portion 23 of the motor housing block 21 of the motor housing unit 2 and the outer peripheral surface of the stator core 11 facing the inner peripheral surface with a fluid. And is formed so as to extend over at least a part of the gear housing block 31 in the axial direction of the motor 10.

The cooling oil level adjustment unit 50 includes a front volume portion 51 closer to the front of the vehicle, a rear volume portion 52 closer to the rear of the vehicle, a front volume portion 51, and a rear volume portion in cross-sectional views in FIGS. 52 and an intermediate volume portion 53 connected to the front and rear.
As shown in FIGS. 7 and 9, when the vehicle is located on a flat road R0 (horizontal plane), the rear volume portion 52 has a cooling oil level upper limit regulating portion at a level position equal to the lower end position 12P of the rotor core 12 of the motor 10. 521. The cooling oil level upper limit regulating portion 521 is a member having a surface portion that regulates the position of the liquid level of the cooling oil 60 in the rear volume portion 52 within its own level position.

Further, front volume section 51 has cooling oil level upper limit regulating section 511 at a higher level than lower end position 12P of rotor core 12 of motor 10 when the vehicle is located on flat road R0 (horizontal plane). The volume 53 does not have the cooling oil level upper limit regulating portion as in the front volume 51 and the rear volume 52, and therefore, the cooling oil 60 can overflow upward in the intermediate volume 53.

  Here, as shown in FIG. 8, when the vehicle is on the uphill road R1, the cooling oil 60 is biased toward the rear volume portion 52 side. The liquid level 61 of the cooling oil 60 is not allowed to rise above the level position, and overflows from the upper open portion on the side of the intermediate volume 53 communicating with the rear volume 52. Therefore, the liquid level 61 of the cooling oil 60 rises to a higher level position than the lower end position 12P of the rotor core 12. That is, the lower part of the rotor core 12 is immersed in the cooling oil 60 to be cooled.

The rise of the liquid level 61 of the cooling oil 60 described above occurs equally in the axial direction of the motor 10 unless the vehicle is inclined in the left-right direction. In other words, the level position of the liquid surface 61 of the cooling oil 60 also rises at the part of the motor 10 on the side of the side housing block 22 where the splash of the cooling oil 60 lifted by the large-diameter gear 5a does not reach, The portion below the rotor core 12 is immersed in the cooling oil 60.
Therefore, when the motor 10 is in a high load state while the vehicle is traveling or accelerating on an uphill road, the cooling effect of the cooling oil 60 on the rotor core 12 also extends remarkably over its entire length in the axial direction, Even when the vehicle is traveling on an uphill or accelerating and the motor 10 is in a high-load state, overheating of the motor 10 is effectively suppressed.

  On the other hand, as shown in FIG. 10, when the vehicle is on the downhill road R2, the cooling oil 60 is biased toward the front volume portion 51 side. However, in the front volume section 51, since the level position of the cooling oil level upper limit regulating section 511 is high, the liquid level 61 of the cooling oil 60 inside is allowed to rise. Therefore, the overflow of the cooling oil 60 as described above does not occur on the side of the intermediate volume section 53 when climbing a hill. Therefore, the lower part of the rotor core 12 is not immersed in the cooling oil 60, and no unnecessary rotation resistance is generated.

Next, the cooling oil level adjusting section 50 common to the motor units 1a and 1b for the vehicles in FIGS. 5 and 6 and the vicinity thereof will be described from different angles with reference to FIGS.
FIG. 11 is a schematic diagram showing a cross section in a direction perpendicular to the axis of the cooling oil level adjusting unit (the rotor shaft 14 of the motor 10), and is a diagram showing how to cut the cross section in the cross-sectional views of FIGS. . 12 is a cross-sectional view taken along the line AA in FIG. 11, FIG. 13 is a diagram showing the motor and the stator removed from FIG. 12, and FIG. It is BB sectional drawing.
In FIGS. 11 to 14, parts corresponding to those in FIGS. 7 to 10 described above are denoted by the same reference numerals, and description thereof is omitted.

  As reconfirmed with reference to FIG. 12, in the rear volume section 52, the liquid level 61 of the cooling oil 60 is regulated by the cooling oil level upper limit regulating section 521. In FIG. 12, the reason that the liquid surface 61 appears above the lower limit position of the rotor core 12 is that the liquid surface 61 is seen from the line AA in FIG. 12, and in fact, the level position of the liquid surface 61 is It stays slightly below the lower limit position of the rotor core 12.

  Further, as reconfirmed with reference to FIG. 13, when the stator core 11 and the rotor core 12 in FIG. 12 are removed and seen through, the level position of the liquid surface 61 is horizontal along the axial direction of the motor 10.

  On the other hand, as seen with reference to FIG. 14, when viewed in cross section along the line BB in FIG. 11, the upper side of such a motor housing block 21 is filled with cooling oil such as the cooling oil level adjustment unit 50. There is no such container-shaped part.

The operation and effect of the vehicle motor unit of the present embodiment described above will be summarized.
(1) In the motor unit 1 for a vehicle according to the present embodiment, the motor housing 2 that houses the motor 10 and the gear housing 3 that houses the gear 30 that transmits the driving force of the motor 10 to the output shafts 101 and 102 are provided. It has a housing 100 which is integrally arranged by being arranged side by side in the axial direction of the motor 10, and is formed so as to rise from a bottom inner surface near a joint portion of the gear housing portion 3 with the motor housing portion 2, and is formed on the front side of the vehicle. A cooling oil level controller 40 having a volume exclusion body 400 having a shape in which the degree of immersion in the cooling oil 60 in the gear housing portion 3 increases or decreases in accordance with the vertical displacement.
For this reason, when the cooling oil 60 is tilted so that the front part of the vehicle is relatively high when climbing a hill and the cooling oil 60 is relatively deviated rearward, the volume exclusion body 400 is more immersed in the cooling oil. The liquid level 61 of the cooling oil 60 rises in proportion to the decrease in the effective volume due to the part immersed in the cooling oil 60. Such a rise in the liquid level 61 is caused by the motor housing portion 2 opposite to the gear housing portion 3 where the splash of the cooling oil 60 generated by the scooping of the cooling oil 60 by the gear portion 30 (the large-diameter gear 5a) does not reach. Occurs equally within. Therefore, as the liquid level 61 of the cooling oil 60 rises, in the motor 10, the lower part of the rotor core 12 is immersed in the cooling oil 60 along the entire length in the axial direction together with the stator core 11. Therefore, when the motor is in a high load state while the vehicle is traveling on an uphill road, the cooling effect of the cooling oil 60 on the rotor core 12 is remarkable over the entire length in the axial direction, and the motor has a high load. In this state, overheating of the motor is effectively suppressed. In this case, since the volume elimination body 400 is provided on the gear housing part 3 side, there is no space between the motor housing part and the stator core. Type)).

(2) In the motor unit 1 for a vehicle according to the present embodiment, in particular, the volume exclusion body has a shape in which the height increases from the front to the rear in the front-rear direction of the vehicle. Therefore, when the vehicle accelerates forward and the cooling oil is relatively deflected rearward due to its inertia force, the volume exclusion body is immersed in the cooling oil more deeply, and the cooling corresponding to the increase in the volume exclusion volume due to this. Oil level rises. When the liquid level of the cooling oil rises, the cooling effect of the cooling oil on the rotor core also becomes remarkable over its entire length in the axial direction, and even if the motor is under a high load, the overheating of the motor is effectively prevented. Is suppressed.

(3) In the motor unit 1 for a vehicle of the present embodiment, particularly, the volume elimination body is formed by a part of the gear housing portion. For this reason, in this type of vehicle motor unit, the cooling oil is provided without the necessity of other components, power means, sensors, etc., only by making the shape of a part of the gear housing part necessarily provided like the above-mentioned volume eliminating body. The level adjuster can be easily configured. Further, the vehicle motor unit can be downsized as a whole.

  The present invention can be implemented with various modifications and alterations other than the above-described embodiments. Therefore, the present invention also covers a vehicle motor unit that is modified and implemented.

DESCRIPTION OF SYMBOLS 1 ... Motor unit for vehicles 2 ... Motor housing part 3 ... Gear housing part 10 ... Motor 30 ... Gear part 40 ... Cooling oil level adjuster 50 ... Cooling oil level adjusting part 51 ... Front volume part 52 ... Back volume part 53 ... Intermediate Volume section 100: Housing 101, 102: Output shaft 400: Volume elimination body 511, 521: Cooling oil level upper limit regulating section

Claims (2)

A motor unit for a vehicle having a housing in which a motor housing for accommodating a motor and a gear housing for accommodating a gear for transmitting a driving force of the motor to an output shaft are joined and arranged in the axial direction of the motor. And
A shape in which the gear housing portion is formed to rise from the bottom inner surface near the joint with the motor housing portion, and the degree of immersion in the cooling oil in the gear housing portion increases or decreases in accordance with vertical displacement of the front side of the vehicle. Equipped with a cooling oil level controller having a volume exclusion body ,
The volume exclusion body is formed by a part of the gear housing portion.
Motor unit for vehicles. The volume exclusion body takes a shape in which a cross section in a direction perpendicular to an axis of the motor increases in height from a front part thereof to a rear part in a front-rear direction of the vehicle,
The vehicle motor unit according to claim 1.

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