JP7517069B2 - Housing for drive device and drive device - Google Patents

Description

The present invention relates to a housing for a drive unit that houses a motor and a speed conversion device. The present invention also relates to a drive unit that houses a motor and a speed conversion device.

Hybrid and electric vehicles use motors and speed converters for drive, which are built into and protected by housings.

Patent document 1 describes a speed conversion device in which the speed conversion device case has multiple mating surfaces with the motor, and the reduction ratio can be changed by changing the mounting orientation of the speed conversion device relative to the motor.

Patent document 2 describes how a motor case and a speed conversion device case are provided separately and the connection between the motor case and the speed conversion device case is made common, allowing the motor to be shared even when different types of speed conversion devices are used.

JP 2018-159416 A JP 2019-120294 A

However, when incorporating both a motor and a speed conversion device into a single housing, it was necessary to prepare housings of different shapes and sizes for each type of motor and speed conversion device, which was costly and time-consuming.

In addition, in the case of Patent Document 1, the installation orientation of the speed conversion device is somewhat limited, and the variations in reduction ratios are also limited.

In addition, while Patent Document 2 allows for a certain degree of component standardization, it is necessary to prepare a different speed conversion device case for each different type of speed conversion device. Furthermore, Patent Document 2 is a technology for sharing motors, and does not assume that the type of motor will change, so if the type of motor changes, both the motor case and the speed conversion device case must be changed.

The object of the present invention is to make the drive unit housing compatible with various types of motors and speed conversion devices.

The present invention provides a housing for a drive device for incorporating a motor and a speed conversion device, the housing having a housing incorporating the motor and the speed conversion device, and a variable section whose length is variable, the housing being divided into a first housing section and a second housing section by a first dividing surface perpendicular to the axial direction of the motor, the second housing section being further divided into a third housing section and a fourth housing section by a second dividing surface parallel to the axial direction of the motor, the motor being disposed in the first housing section, the variable section being inserted into the second dividing surface, and the speed conversion device being disposed in the second housing section . a first input gear joined to a motor shaft of a motor, a first output gear meshing with the first input gear, an intermediate shaft joined to the first output gear, a second input gear joined to the intermediate shaft, a second output gear meshing with the second input gear, and an output shaft joined to the second output gear and protruding to the outside from the housing for the drive device, wherein one bearing of the motor shaft is disposed in the first housing portion and the other bearing is disposed in the third housing portion, the intermediate shaft is disposed in the fourth housing portion, and the output shaft is disposed in the third housing portion .

The variable section may have a bellows structure that allows the length to be changed.

The variable section may have a dimension adjustment section with a bellows structure made of rubber, and a dimension maintenance section that maintains the length of the dimension adjustment section.

The dividing plane may be perpendicular to the axial direction of the motor.

The speed conversion device has a first input gear joined to the motor shaft of the motor, a first output gear meshing with the first input gear, an intermediate shaft joined to the first output gear, a second input gear joined to the intermediate shaft, a second output gear meshing with the second input gear, and an output shaft joined to the second gear and protruding to the outside from the drive device housing, and the housing is divided into four parts, in the order of a first housing part, a second housing part, a third housing part, and a fourth housing part, by three dividing planes perpendicular to the axial direction of the motor, one bearing of the motor shaft is arranged in the first housing part and the other bearing is arranged in the third housing part, one bearing of the intermediate shaft is arranged in the second housing part and the other bearing is arranged in the fourth housing part, and one bearing of the output shaft is arranged in the third housing part and the other bearing is arranged in the fourth housing part.

Another aspect of the present invention is a drive device that includes a motor, a speed conversion device attached to the motor, and a housing for the drive device of the present invention that incorporates the motor and the speed conversion device.

The present invention makes it possible to realize a housing for a drive unit with variable dimensions, which allows it to accommodate a variety of motors and speed conversion devices and allows the housing to be shared.

FIG. 2 is a diagram showing the configuration of a drive device according to the first embodiment. FIG. 2 is a diagram showing the configuration of a housing 3. FIG. 13 is a diagram showing the configuration of a drive device according to a second embodiment.

Specific examples of the present invention will be described below with reference to the drawings, but the present invention is not limited to these examples.

Figure 1 shows the configuration of the drive device of Example 1. As shown in Figure 1, the drive device of Example 1 has a motor 1, a speed conversion device 2, and a housing 3 that houses the motor 1 and the speed conversion device 2.

The motor 1 is composed of a rotor 10, a stator 11, and a motor shaft 12.

The stator 11 is composed of a stator core and coils. The stator core is a thick cylinder with multiple slots that penetrate the cylinder in the axial direction and are equally spaced circumferentially. The stator core is made of laminated steel plates, for example. The coils are distributed wound through the slots of the stator core.

The rotor 10 is cylindrical and is arranged coaxially within the cylinder of the stator 11. The rotor 10 is made of laminated steel plates with magnets embedded inside. When a current is passed through the coil of the stator 11, a rotating magnetic field is generated, which causes the rotor 10 to rotate around the rotation axis.

The motor shaft 12 passes through the center of the rotor 10, and the rotor 10 and the motor shaft 12 are joined. When the rotor 10 rotates, the motor shaft 12 also rotates, and this becomes the output to the speed conversion device 2. Both ends of the motor shaft 12 are rotatably supported by bearings 13 and 14.

The speed conversion device 2 is a reducer that reduces the rotational speed of the motor 1 and improves the torque. Alternatively, it may be a speed increaser that increases the rotational speed of the motor 1 and reduces the torque, or a transmission that allows the rotational speed to be adjusted. The speed conversion device 2 has a first input gear 20, an intermediate shaft 21, a first output gear 22, a second input gear 23, an output shaft 24, and a second output gear 25. The first input gear 20, the first output gear 22, the second input gear 23, and the second output gear 25 are all spur gears.

The first input gear 20 is joined to one end of the motor shaft 12. The intermediate shaft 21 is arranged at a predetermined distance from the motor shaft 12, with its axial direction parallel to the axial direction of the motor shaft 12. Both ends of the intermediate shaft 21 are rotatably supported by bearings 26 and 27. The first output gear 22 and the second input gear 23 are joined to the intermediate shaft 21 at a predetermined interval. The first input gear 20 and the first output gear 22 are arranged so that their teeth mesh with each other. The output shaft 24 is coaxial with the motor shaft 12 and is arranged at a predetermined distance from the intermediate shaft 21. Both ends of the output shaft 24 are rotatably supported by bearings 28 and 29. The second output gear 25 is joined to one end of the output shaft 24. The second input gear 23 and the second output gear 25 are arranged so that their teeth mesh with each other. One end of the output shaft 24 protrudes outside the housing 3 via the bearing 29. The speed conversion device 2 adjusts the gear ratio to reduce the rotational speed of the motor 1 to a desired value, and adjusts the torque of the output shaft 24 to a desired value.

The housing 3 is composed of a housing 30 that houses the motor 1 and the speed conversion device 2, and a variable section 31. The housing 3 seals the motor 1 and the speed conversion device 2, and is configured so that cooling oil can circulate inside the housing 3 by a circulation structure (not shown).

The housing 30 is a hollow rectangular parallelepiped made of metal. The material of the housing 30 is, for example, aluminum. The housing 30 is divided into four parts by three parallel faces, dividing planes A, B, and C. The four parts are referred to as housings 30a, 30b, 30c, and 30d, respectively. In the first embodiment, the shape of the housing 30 is a rectangular parallelepiped, but any shape that can accommodate the motor 1 and the speed conversion device 2 may be used. The dividing plane A is provided at a position between the bearing 13 and the rotor 10 (or the stator 11) of the motor 1. The dividing plane B is provided at a position between the rotor 10 (or the stator 11) and the bearing 14. The dividing plane C is provided at a position between the second output gear 25 and the bearing 29.

Housings 30a and 30b are joined at division surface A and fastened and fixed by bolts 32. Housings 30b and 30c are separated at a distance by division surface B, variable part 31 is inserted at the separation position, and housings 30b and 30c are connected by variable part 31. Housings 30c and 30d are joined at division surface C and fastened and fixed by bolts 32.

As shown in Figures 1 and 2, the variable section 31 is composed of a dimension adjustment section 33 whose axial length is variable, and a dimension maintenance section 34 that maintains the axial length.

The dimension adjustment section 33 is a rectangular tube with bellows-like rubber sides, and the axial dimension of the tube changes as the bellows expand and contract. The dimension adjustment section 33 is also positioned so that the top and bottom surfaces of the tube roughly coincide with the dividing plane B.

In the first embodiment, bellows rubber is used as the dimension adjustment section 33, but other structures may be used as long as the axial length is variable. For example, a double cylindrical structure may be used, and a spigot structure may be used in which the overall length is variable by adjusting the length at the overlapping portion. Also, for example, a spacer structure may be used in which multiple spacers made of multiple plates combined into a square tube shape are used to adjust the dimensions. When using rubber as in the first embodiment, a material with a heat resistance of 100°C or more is preferable, taking into account the heat generated by the motor 1. Also, taking into account the leakage of the magnetic field generated by the motor 1 from the housing 3, it is preferable to configure the rubber portion to be covered with a metal material.

The dimension maintaining section 34 is composed of a stud bolt 36 and a spacer 37. The stud bolts 36 are arranged on the inside of the corners of the square tube of the dimension adjusting section 33. The stud bolts 36 have male threads on both ends and engage with female threads 38 provided at the corners of the housings 30b and 30c. By changing the engagement width between the stud bolts 36 and the female threads 38, the distance between the housings 30b and 30c can be adjusted and the length of the dimension adjusting section 33 can be maintained. In addition, the spacer 37 is engaged with the bolt 32 that fixes the housings 30b and 30c, thereby maintaining the distance between the housings 30b and 30c, and thus maintaining the length of the dimension adjusting section 33.

In the first embodiment, both the stud bolt 36 and the spacer 37 are used as the dimension maintaining portion 34 to ensure the strength of the variable portion 31, but only one of them may be used. Also, any structure other than the stud bolt 36 or the spacer 37 may be used as long as it can maintain the length of the dimension adjusting portion 33.

In this way, the housing 3 has a structure in which the variable portion 31 is inserted into the dividing surface B, and the axial length of the variable portion 31 can be changed by changing the lengths of the stud bolts 36 and spacers 37. Therefore, even if the axial length of the motor 1 (axial length of the rotor 10 and stator 11) or the axial length of the first input gear 20 and first output gear 22 change due to differences in load capacity, there is no need to design a dedicated housing to accommodate this, and the housing 3 can be shared.

Next, the arrangement of the bearings in the housing 30 will be described. The bearing 13 that rotatably supports one end of the motor shaft 12 is arranged in the housing 30a. The bearing 14 that rotatably supports the other end (first input gear 20 side) of the motor shaft 12 is arranged in the housing 30c. Therefore, even if the axial length of the housing 3 changes due to the variable part 31, the positions of the bearings 13 and 14 do not change.

In addition, the bearing 26 that rotatably supports one end of the intermediate shaft 21 (first output gear 22 side) is disposed in the housing 30b, and the bearing 27 that rotatably supports the other end of the intermediate shaft 21 (second input gear 23 side) is disposed in the housing 30d. Therefore, even if the axial length of the housing 3 changes due to the variable part 31, the positions of the bearings 26 and 27 do not change. Note that even if the bearing 26 is disposed in the housing 30a or the bearing 27 is disposed in the housing 30c, the positions of the bearings 26 and 27 can be prevented from changing in the same manner.

In addition, bearing 28, which rotatably supports one end of output shaft 24 (the second output gear 25 side), is disposed in housing 30c, and bearing 29, which rotatably supports the other end of output shaft 24 (the side that is taken out of housing 3), is disposed in housing 30d. In this case, variable portion 31 is not positioned between bearings 28 and 29. Therefore, even if variable portion 31 changes the axial length of housing 3, the positions of bearings 28 and 29 do not change.

In this way, in the drive device of Example 1, the housing 30 is divided into four parts 30a, 30b, 30c, and 30d, with one bearing 13 of the motor shaft 12 arranged in the housing 30a, one bearing 26 of the intermediate shaft 21 arranged in the housing 30b, the other bearing 14 of the motor shaft 12 and one bearing 28 of the output shaft 24 arranged in the housing 30c, and the other bearing 27 of the intermediate shaft 21 and the other bearing 29 of the output shaft 24 arranged in the housing 30d. Therefore, even if the axial length of the motor 1 or gear changes, the axial dimension of the housing 3 can be changed without changing the bearing arrangement. As a result, the housing 3 can be further shared.

In the first embodiment, the variable part 31 is inserted only in the dividing surface B, but the variable part 31 may be inserted in the dividing surface A or the dividing surface C, or in two or more of the dividing surfaces A, B, and C. When the variable part 31 is inserted in the dividing surface A, it is possible to accommodate changes in the axial length of the motor 1. When the variable part 31 is inserted in the dividing surface C, it is possible to accommodate changes in the axial length of the second input gear 23 and the second output gear 25.

As described above, the drive device of Example 1 has a variable section 31 in the housing 3 whose axial length is variable, and the axial dimension of the housing 3 can be changed by the variable section 31. Therefore, even if the axial dimension of the motor 1 or the speed conversion device 2 changes, the motor 1 and the speed conversion device 2 can be built in by adjusting the axial dimension of the housing 3 by the variable section 31, and the housing 3 can be shared. This allows the cost of the drive device to be reduced.

Figure 3 shows the configuration of the drive device of Example 2. The drive device of Example 2 is composed of a motor 1 and a speed conversion device 2 having the same structure as those of Example 1, and a housing 203 that houses the motor 1 and the speed conversion device 2.

The housing 203 has a case 230 and a variable part 231. The case 230 is composed of six parts, case 230a to 230f. It is divided into three parts, case 230a, 230b, and 230c, at dividing planes A and B in the axial direction of the motor 1. Furthermore, case 230d and 230e are joined at dividing planes C and D on the side of case 230c, and case 230f is joined at dividing plane E on the side of case 230e. Furthermore, variable part 231, which has a structure similar to that of variable part 31 in Example 1, is inserted into dividing planes C, D, and E.

The rotor 10 and stator 11 of the motor 1 are disposed in the housing 230b, one bearing 13 of the motor shaft 12 is disposed in the housing 230a, and the other bearing 14 is disposed in the housing 230c. The first input gear 20 of the speed conversion device 2 is disposed in the housing 230c, and the first output gear 22 is disposed across the housings 230c and 230e. The bearings 26 and 27 of the intermediate shaft 21 are disposed in the housing 230e. The second input gear 23 is disposed in the housing 230e. The second output gear 25 is disposed across the housings 230e and 230c, and the bearings 28 and 29 of the output shaft 24 are disposed in the housing 230c.

As described above, the drive device of Example 2 has a variable section 231 whose radial length is variable in the housing 203, and the variable section 231 makes it possible to change the radial dimension of the housing 203. Therefore, even if the radial dimension of the speed conversion device 2 changes, the motor 1 and the speed conversion device 2 can be built in by adjusting the radial dimension of the housing 203 with the variable section 231, and the housing 203 can be shared. This allows the cost of the drive device to be reduced.

The configurations of the motor 1 and the speed conversion device 2 are not limited to those shown in the first embodiment, and the present invention can be applied to motors 1 and speed conversion devices 2 of any configuration. For example, in the first embodiment, the motor shaft 12 and the output shaft 24 are coaxial, but the present invention can also be applied to configurations in which the shafts are parallel, or where the motor shaft 12 and the output shaft 24 are perpendicular to each other.

In addition, in the first embodiment, a variable section whose length is variable in the axial direction of the motor is provided, and in the second embodiment, a variable section whose length is variable in the radial direction of the motor is provided, but of course both may be provided. For example, in the second embodiment, a variable section whose length is variable in the axial direction of the motor may be provided on dividing surface B of housing 203.

The drive unit housing of the present invention can be applied to vehicles such as hybrid cars and electric cars.

1: Motor 2: Speed conversion device 3: Housing 10: Rotor 11: Stator 12: Motor shaft 20: First input gear 21: Intermediate shaft 22: First output gear 23: Second input gear 24: Output shaft 25: Second output gear 13, 14, 26-29: Bearings 30, 30a-30d: Housing 31: Variable section 33: Dimension adjustment section 34: Dimension maintenance section

Claims (4)

A housing for a drive device for housing a motor and a speed conversion device, comprising:
a housing that houses the motor and the speed conversion device;
A variable section whose length is variable;
having
the housing is divided into a first housing section and a second housing section by a first dividing surface perpendicular to the axial direction of the motor, and the second housing section is further divided into a third housing section and a fourth housing section by a second dividing surface parallel to the axial direction of the motor;
The motor is disposed within the first housing portion,
The variable portion is inserted into the second divided surface,
The speed conversion device is
Located within the second housing portion,
A first input gear connected to a motor shaft of the motor;
a first output gear that meshes with the first input gear;
an intermediate shaft joined to the first output gear;
A second input gear joined to the intermediate shaft;
a second output gear that meshes with the second input gear;
an output shaft connected to the second output gear and protruding from the drive device housing to the outside;
having
one bearing of the motor shaft is disposed in the first housing portion, and the other bearing is disposed in the third housing portion;
the intermediate shaft is disposed in the fourth housing portion,
The output shaft is disposed in the third housing portion.
A housing for a drive unit. The housing for a drive unit according to claim 1, characterized in that the variable section has a structure in which the length can be changed by a bellows. The housing for a drive unit according to claim 1, characterized in that the variable portion has a dimension adjustment portion having a bellows structure made of rubber, and a dimension maintaining portion that maintains the length of the dimension adjustment portion. A motor;
a speed change device attached to the motor ;
A housing for a drive device according to any one of claims 1 to 3 , which houses the motor and the speed conversion device;
A drive device comprising: