Drive unit

Abstract

To provide a drive unit for a vehicle.SOLUTION: A drive unit for a vehicle comprises: a motor case which accommodates a motor; a first case which accommodates a gear unit mechanically connected with the motor; and a second case which accommodates a power conversion unit electrically connected with the motor. The first and second cases are fastened to the motor case by a plurality of fastening members. The plurality of fastening members comprise at least one common fastening member which jointly fastens the first and second cases to the motor case.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The technology disclosed in this specification relates to a drive device for a vehicle. [Background technology]

[0002] The vehicle drive device disclosed in Patent Document 1 has a configuration in which a motor case that houses a motor, a gear case that houses a gear unit, and a power conversion unit case that houses a power conversion unit are fastened together. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 9,692,277 Summary of the Invention [Problem to be solved by the invention]

[0004] In an integrated drive unit, it is necessary to ensure the capacity of the gear case and the power conversion unit case while reducing the size of the drive unit. [Means for solving the problem]

[0005] The present specification discloses a drive device for a vehicle that includes a motor case that houses a motor, a first case that houses a gear unit that is mechanically connected to the motor, and a second case that houses a power conversion unit that is electrically connected to the motor. The first and second cases are fastened to the motor case by a plurality of fastening members. The plurality of fastening members includes at least one common fastening member that fastens the first and second cases together to the motor case.

[0006] In a configuration using fastening members to fasten the cases together, generally, space is required to arrange the fastening members. As a result, there are cases where the capacity of the case cannot be secured, or where the physical size of the drive device becomes large. According to the above configuration, a common fastening member is included that fastens the first case and the second case together to the motor case. This makes it possible to reduce the total number of fastening members required. Since the total number of fastening members can be reduced, the space required to arrange the fastening members can be reduced. It is possible to secure the capacity of the first case and the second case, while also reducing the physical size of the drive device. [Brief description of the drawings]

[0007] [Figure 1] 1 is a cross-sectional view showing a schematic configuration of a drive device 1. FIG. [Diagram 2] FIG. [Diagram 3] FIG. 2 is an exploded plan view of the casing 10. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] At the location of the at least one common fastening member, the second case may be disposed above the first case.

[0009] According to the above configuration, the first case and the second case can be fastened together to the motor case.

[0010] The first case may include a first flange extending along an outer periphery thereof and fixed to the motor case by a portion of the plurality of fastening members. The second case may include a second flange extending along an outer periphery thereof and fixed to the motor case by a portion of the plurality of fastening members. The portion of the first flange may have an overlapping section located between the motor case and the second flange. The at least one common fastening member may include at least one first common fastening member located in the overlapping section.

[0011] According to the above configuration, by using the first common fastening member in the overlapping section of the first flange and the second flange, it is possible to reduce the total number of fastening members.

[0012] The first case may further include an extension extending from one end of the overlapping section to the other end along an outer edge of the second case between the motor case and the second flange, and the at least one common fastening member may include at least one second common fastening member located on the extension.

[0013] According to the above configuration, the entire outer edge of the second case can be fastened by the first common fastening member and the second common fastening member.

[0014] The second flange may have an average thickness greater than the average thickness of the first flange.

[0015] Since the fastening member comes into contact with the second flange, a large force is applied to the second flange by the fastening member. With the above configuration, the strength of the second flange can be made higher than that of the first flange, making it possible to suppress damage to the second flange.

[0016] The motor may include a motor shaft. At least a portion of the second case may overlap with the first case in a direction perpendicular to a central axis of the motor shaft.

[0017] According to the above-described configuration, the amount of protrusion of the second case in the direction of the central axis of the motor shaft can be reduced, making it possible to reduce the size of the drive device.

[0018] At least a portion of the second case may overlap with the motor in the central axial direction of the motor shaft.

[0019] According to the above-mentioned configuration, the amount of protrusion of the second case in the direction perpendicular to the central axis of the motor shaft can be reduced, making it possible to reduce the size of the drive device.

[0020] When viewed from the central axis direction of the motor shaft, the second case may be disposed along a part of a circumference centered on the motor shaft. The range in which the second case is disposed in the rotational direction of the motor may be 180° or more around the motor shaft.

[0021] According to the above configuration, the space around the motor shaft can be effectively utilized.

[0022] The motor may include a motor shaft. Each of the plurality of fastening members may include a bolt. A longitudinal direction of the bolt may be substantially parallel to a central axis of the motor shaft.

[0023] The first case may define a space between the motor case and the first case for accommodating the gear unit.

[0024] The second case may define a space between the motor case and the second case for accommodating the power conversion unit. EXAMPLES

[0025] (Configuration of driving device 1) FIG. 1 is a cross-sectional view showing a schematic configuration of a drive unit 1 of this embodiment. The drive unit 1 is an integrated device in which a motor, a gear unit, and a power conversion unit for controlling the motor are housed in the same casing. The directions FR, RH, and UP indicate the orientation of the drive unit 1 with respect to the vehicle (electric vehicle) when the drive unit 1 is mounted on the vehicle. The direction FR indicates the front in the longitudinal direction of the vehicle. The direction RH indicates the right in the lateral direction (or width direction) of the vehicle. The direction UP indicates the upward direction in the vertical direction of the vehicle. The same applies to other drawings. In FIG. 1, multiple shafts (motor shaft 43, countershaft 52, drive shafts 57L and 57R) are shown developed so as to be located on the same plane.

[0026] The drive device 1 is controlled by a control device 2. The control device 2 includes a CPU, a RAM, a ROM, an input / output interface, etc. The control device 2 is connected to a power conversion unit 21 and the like by signal lines (not shown).

[0027] The drive unit 1 includes a casing 10. The casing 10 includes a first case 11, a second case 12, and a motor case 13. The first case 11, the second case 12, and the motor case 13 may be cast metal.

[0028] The motor case 13 includes a motor compartment 31. A motor 40 is stored in the motor compartment 31. In other words, the motor case 13 houses the motor 40. The motor 40 includes a stator 41, a rotor 42, and a motor shaft 43. The stator 41 has a cylindrical shape. The rotor 42 is rotatably disposed inside the stator 41. The motor shaft 43 has a central axis CA.

[0029] The motor case 13 also has an opposing surface 13s that faces the first case 11 and the second case 12. A motor shaft hole MH and a drive shaft hole DH1 are formed in the opposing surface 13s. The motor shaft 43 passes through the motor shaft hole MH. The left drive shaft 57L passes through the drive shaft hole DH1.

[0030] The first case 11 has a box shape with one open side. The first case 11 is fastened to the opposing surface 13s so that the open side is closed by the opposing surface 13s. The manner of fastening will be described later. As a result, a first space SP1 is defined between the motor case 13 and the first case 11. The gear unit 50 is stored in the first space SP1. In other words, the first case 11 houses the gear unit 50.

[0031] The gear unit 50 includes a shaft gear 51, a countershaft 52, a first counter gear 53, a second counter gear 54, a ring gear 55, and a differential gear 56. The shaft gear 51 is attached to the motor shaft 43. This mechanically connects the gear unit 50 and the motor 40. The countershaft 52 is attached to the first counter gear 53 and the second counter gear 54. The first counter gear 53 meshes with the shaft gear 51. The second counter gear 54 meshes with the ring gear 55. The ring gear 55 is attached to the differential gear 56. A pair of drive shafts 57L and 57R extend in the vehicle width direction from the differential gear 56. The drive shaft 57R passes through a drive shaft hole DH2 formed in the first case 11. A reservoir 58 is provided at the bottom of the first space SP1. Oil 57 is stored in the reservoir 58. A portion of the gear unit 50 is immersed in oil 57 stored in a reservoir 58 .

[0032] The second case 12 has a box shape with one side open. The second case 12 is fastened to the opposing surface 13s so that the opening surface is closed by the opposing surface 13s. The manner of fastening will be described later. As a result, a second space SP2 is defined between the motor case 13 and the second case 12. The power conversion unit 21 is stored in the second space SP2. In other words, the second case 12 houses the power conversion unit 21. The power conversion unit 21 is a part for controlling the power supplied to the motor 40 and the generated power. Examples of components included in the power conversion unit 21 include an inverter and a converter. The power conversion unit 21 is electrically connected to the motor 40 by a bus bar 22.

[0033] (Configuration of casing 10) Fig. 2 shows a perspective view of the casing 10. Fig. 3 shows an exploded plan view of the casing 10. Note that in Figs. 2 and 3, the various components housed inside the casing 10 are omitted. In Fig. 2, the position of the motor shaft 43 is indicated by a dotted line.

[0034] The first case 11 has a first flange 11f extending along the outer periphery of the first case 11. In FIG. 3, the first flange 11f is formed in the overlapping section OS and section SS. The second case 12 has a second flange 12f extending along the outer periphery of the second case 12. The motor case 13 has a motor case flange 13f extending along the outer periphery of the motor case 13. A plurality of fastening holes 11h are arranged in the first flange 11f. A plurality of fastening holes 12h are arranged in the second flange 12f. A plurality of fastening holes 13h are arranged in the motor case flange 13f and the opposing surface 13s.

[0035] As shown in Fig. 3, a part of the first flange 11f has an overlapping section OS. The overlapping section OS is a region where the second flange 12f overlaps the first flange 11f. In other words, in the overlapping section OS, the first flange 11f is located between the opposing surface 13s of the motor case 13 and the second flange 12f.

[0036] The first case 11 also has an extension 14 extending from the end E1 to the end E2 of the overlapping section OS. The extension 14 is a frame-shaped member extending along the outer edge of the second case 12. The extension 14 has the same thickness as the first flange 11f. The extension 14 is formed integrally with the first case 11. A plurality of fastening holes 14h are arranged in the extension 14. The first flange 11f and the extension 14 arranged in the overlapping section OS form a base having a closed ring shape. An opening area OA is formed on the inside of the ring-shaped base. The ring-shaped base is formed so as to overlap the second flange 12f by one revolution when the second case 12 is assembled. That is, the ring-shaped base also functions as a spacer ring.

[0037] The first case 11 and the second case 12 are fastened to the motor case 13 by a plurality of bolts 60. The longitudinal direction of the plurality of bolts 60 is substantially parallel to the central axis CA of the motor shaft 43. A specific description will be given. The plurality of bolts 60 includes at least one first common bolt 61 arranged in the overlapping section OS. In other words, the second case 12 is arranged on the first case 11 at the position of the first common bolt 61. In the overlapping section OS, the fastening hole 12h of the second flange 12f, the fastening hole 11h of the first flange 11f, and the fastening hole 13h of the motor case 13 are aligned. The first common bolt 61 is inserted into the fastening hole 13h through the fastening holes 12h and 11h. As a result, the first case 11 and the second case 12 are fastened together to the motor case 13.

[0038] The bolts 60 also include at least one second common bolt 62 disposed in the extension section ES where the extension 14 exists. In the extension section ES, the second common bolt 62 passes through the fastening holes 12h and 14h and is inserted into the fastening hole 13h. This causes the extension 14 and the second case 12 to be fastened together to the motor case 13. In other words, the extension 14 is located between the motor case 13 and the second flange 12f.

[0039] In the first flange 11f, a section SS other than the overlap section OS is provided with a bolt 60. In the section SS, the bolt 60 passes through the fastening hole 11h and is inserted into the fastening hole 13h (see FIG. 2). This fastens the first case 11 to the motor case 13.

[0040] The average thickness of the second flange 12f is greater than the average thickness of the first flange 11f. The effect will be explained. In the region where the first case 11 and the second case 12 are fastened together to the motor case 13, the bolts come into contact with the second flange 12f. Therefore, the force applied by the bolts is greater on the second flange 12f than on the first flange 11f. Therefore, by making the strength of the second flange 12f greater than the strength of the first flange 11f, it is possible to suppress damage to the second flange 12f.

[0041] (Positional relationship between first case 11 and second case 12) As shown in FIG. 1, a space is formed in the area on the opposite side of the motor shaft 43 from the gear unit 50 due to the dimensional difference between the motor 40 and the gear unit 50. The second case 12 is disposed in this space. That is, at least a part of the second case 12 overlaps with the first case 11 in the direction D1 perpendicular to the central axis CA of the motor shaft 43. This allows the space around the motor shaft 43 to be effectively utilized. Therefore, the amount of protrusion of the second case 12 in the central axis direction D2 of the motor shaft 43 can be reduced. This allows the size of the drive device 1 to be reduced.

[0042] In addition, in the central axis direction D2, at least a portion of the second case 12 overlaps with the motor 40. This also makes it possible to effectively utilize the space around the motor shaft 43. As a result, the amount of protrusion of the second case 12 in the direction D1 perpendicular to the central axis CA can be reduced.

[0043] 2, when viewed from the central axis direction D2 of motor shaft 43, second case 12 is arranged along a part of a circumference centered on motor shaft 43. The range in which second case 12 is arranged in the rotational direction of the motor is 180° or more around motor shaft 43. This makes it possible to ensure a sufficient capacity of second case 12.

[0044] (effect) In a configuration in which the cases are fastened using bolts, it is generally necessary to secure space such as a tool gap around the bolt fastening portion. The more the number of bolt fastening portions, the larger the required space becomes, and the capacity of the case may be compressed. In the technology of this specification, the first case 11 and the second case 12 can be fastened together to the motor case 13 using the first common bolt 61 in the overlapping section OS of the first flange 11f and the second flange 12f. This makes it possible to reduce the total number of bolts required, and therefore the space required for the bolts. It is possible to secure the capacity of the first case 11 and the second case 12, and to reduce the size of the drive unit 1.

[0045] If the extension portion 14 were not present, a step of the thickness of the first flange 11f would be formed between the overlap section OS and the extension section ES (see FIG. 3). The step may make it difficult to ensure sealing. With the technology of this specification, by providing the extension portion 14, it is possible to align the heights of the overlap section OS and the extension section ES. This makes it possible to improve the sealing performance of the second case 12.

[0046] In the technology of the present specification, a spacer ring can be formed by the first flange 11f and the extension portion 14. Since the spacer ring can function as a cushion, it is possible to suppress vibration of the second case 12.

[0047] Although the embodiments have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes to the specific examples exemplified above. The technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or drawings achieves multiple objectives simultaneously, and achieving one of the objectives itself has technical utility.

[0048] (Modification) The positional relationship between the first case 11 and the second case 12 may be various. For example, the second case 12 may be disposed above the first case 11. In this case, a second space SP2 may be defined between the first case 11 and the second case 12. Even in such an embodiment, by providing the overlapping section OS, the total number of bolts required can be reduced.

[0049] The functions of the first case 11 and the second case 12 may be interchanged. That is, the first case 11 may house the power conversion unit 21, and the second case 12 may house the gear unit 50.

[0050] First case 11 does not necessarily have to include extension 14. Furthermore, extension 14 may be a separate component from first case 11.

[0051] The vehicle in which the drive device of this specification is installed is not limited to an electric vehicle. The drive device of this specification can be installed in, for example, a hybrid vehicle or a plug-in hybrid vehicle. In this case, the drive device of this specification may house multiple motors in a casing, or may house a planetary gear mechanism. The drive device of this specification can also be applied to vehicles that use an electric motor for at least part of the driving, such as a fuel cell vehicle. [Explanation of symbols]

[0052] 1: Drive unit 10: Casing 11: First case 11f: First flange 12: Second case 12f: Second flange 13: Motor case 14: Extension 40: Motor 50: Gear unit 60: Bolt 61: First common bolt 62: Second common bolt

Claims

1. A drive device for a vehicle, comprising: A motor case that houses a motor; a first case that houses a gear unit that is mechanically connected to the motor; a second case that accommodates a power conversion unit electrically connected to the motor; Equipped with the first case and the second case are fastened to the motor case by a plurality of fastening members, the plurality of fastening members include at least one common fastening member that fastens the first case and the second case together to the motor case; Drive unit.

2. The drive device according to claim 1 , wherein the second case is disposed above the first case at the location of the at least one common fastening member.

3. the first case includes a first flange extending along an outer circumferential edge thereof and fixed to the motor case by some of the plurality of fastening members; the second case includes a second flange extending along an outer circumferential edge thereof and fixed to the motor case by some of the fastening members; a portion of the first flange having an overlapping section located between the motor case and the second flange, The drive device according to claim 2 , wherein the at least one common fastening member includes at least one first common fastening member located in the overlapping section.

4. The first case further includes an extension portion extending from one end to the other end of the overlapping section along an outer edge of the second case between the motor case and the second flange, The drive arrangement of claim 3 , wherein the at least one common fastening member includes at least one second common fastening member located on the extension.

5. The drive apparatus of claim 3 , wherein an average thickness of the second flange is greater than an average thickness of the first flange.

6. the motor includes a motor shaft; The drive device according to claim 1 , wherein at least a portion of the second case overlaps with the first case in a direction perpendicular to a central axis of the motor shaft.

7. The drive device according to claim 6 , wherein at least a portion of the second case overlaps with the motor in a central axial direction of the motor shaft.

8. the second case is disposed along a part of a circumference centered on the motor shaft when viewed from a central axis direction of the motor shaft, The drive device according to claim 7 , wherein an arrangement range of the second case in a rotation direction of the motor is 180° or more around the motor shaft.

9. the motor includes a motor shaft; Each of the plurality of fastening members includes a bolt, The drive device according to claim 1 , wherein a longitudinal direction of the bolt is substantially parallel to a central axis of the motor shaft.

10. The drive device according to claim 1 , wherein the first case defines a space between the motor case and the first case for accommodating the gear unit.

11. The drive device according to claim 1 , wherein the second case defines a space between the motor case and the second case for accommodating the power conversion unit.

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