JP6209127B2 - Motor structure - Google Patents

Description

  The present invention relates to a motor structure including a motor.

  In a vehicle including a motor as a power source, the power of the motor is transmitted to the transmission via a motor shaft or the like fixed to the rotor, and further acts on the drive wheels via a differential device. Further, vibration is generated as the motor is driven, and the following techniques are disclosed as techniques for suppressing such vibration.

  For example, in Patent Document 1, an input shaft for inputting power from an internal combustion engine, an output shaft arranged on one axis with respect to the input shaft and interlocking with drive wheels, and a first arranged on the above-described first shaft. And a second electric motor are described. A cylindrical rotor shaft is installed on the radially inner side of the rotor of each electric motor, and this rotor shaft is rotatably supported by a plurality of bearings.

  Patent Document 2 describes that a dynamic damper is press-fitted and fixed at a predetermined position in the axial direction in a cylindrical propeller shaft.

  Patent Document 3 describes that a shaft fixed to the inner peripheral surface of the rotor and protruding from the rotor in the axial direction is rotatably supported by a bearing. In addition, each bearing installed in the both ends of a shaft is installed in the outer peripheral surface of this shaft.

Japanese Patent No. 4059876 JP 2004-150543 A JP 2013-207930 A

  However, in the technique described in Patent Document 1, bearings are installed so as to sandwich the rotor shaft in the radial direction, and bearings are installed at both ends of the rotor shaft in the axial direction. That is, four bearings are required to rotatably support the rotor shaft. Thus, since the number of bearings increases, there exists a problem of causing an increase in manufacturing cost.

  Patent Document 2 describes a configuration in which a dynamic damper is installed in a propeller shaft, but does not describe a configuration for suppressing motor vibration.

  In the technique described in Patent Document 3, as described above, each bearing that supports both ends of the shaft is installed on the outer peripheral surface of the shaft. Therefore, it is necessary to secure the length that the shaft projects from the rotor in order to install the bearing, and there is a problem that the width of the rotating electrical machine in the axial direction becomes large.

  Then, this invention makes it a subject to provide the motor structure which can suppress the vibration of a motor while aiming at simplification of a structure.

  As means for solving the above-described problems, a motor structure according to the present invention includes a cylindrical rotor, a stator disposed on the radially outer side of the rotor, and an outer shape fixed to an inner peripheral surface of the rotor. A motor having a cylindrical motor shaft, a power transmission device having an outer cylindrical gear shaft that rotates integrally with the motor shaft, and transmitting power to and from the rotor; the motor; and A state in which the power transmission device is accommodated and has a case body in which a hole is formed on one end side on the central axis of the motor, and an extending portion facing the inside of the one end side of the motor shaft, and the hole is closed And a split case fixed to the case main body, and a first case that is interposed between the inner peripheral surface on the one end side of the motor shaft in the radial direction and the extending portion, and rotatably supports the motor shaft. Fixed to the bearing and the case body And a second bearing that rotatably supports the motor shaft and the gear shaft, and is fixed to the case body and installed on the other end side of the gear shaft. And a third bearing that rotatably supports the gear shaft, and the vicinity of the one end of the gear shaft is splined to the motor shaft, and corresponds to the second bearing in the axial direction of the gear shaft. The portion to be fitted is fitted to the motor shaft.

According to such a configuration, the vicinity of one end of the gear shaft is splined to the motor shaft. Therefore, when one of the motor shaft and the gear shaft rotates, the power of this one can be transmitted to the other.
Further, a portion of the gear shaft corresponding to the second bearing in the axial direction is fitted to the motor shaft. Only the spline coupling described above may cause a slight gap between the motor shaft and the gear shaft in the radial direction. However, when the gear shaft is fitted to the motor shaft, the backlash in the radial direction is eliminated and the motor is removed. Do not amplify the vibration.

Also, by installing the first bearing on the inner peripheral surface of the motor shaft (that is, inside the motor shaft), the axial width of the motor shaft compared to the case where the first bearing is installed on the outer peripheral surface of the motor shaft. Can be shortened, and the motor structure can be made compact.
Furthermore, by supporting the motor shaft and the gear shaft with the second bearing, the number of bearings can be reduced as compared with the case of supporting these with separate bearings, and the motor structure can be simplified. .

Further, one end side of the gear shaft is pivotally supported by the second bearing, and the other end side of the gear shaft is pivotally supported by the third bearing. In this way, by supporting the gear shaft with both ends, the radial deflection of the gear shaft can be suppressed.
In addition, by providing a split case that is fixed to the case body with the hole closed, for example, a spindle is installed in the split case from one end during assembly work, and another spindle is installed on the motor shaft from the other end. By doing so, it can be pressed from both sides in the axial direction. Therefore, it is possible to appropriately perform the assembling work when the stator and the rotor are installed on the same axis.

  Moreover, it is preferable that the said motor shaft is provided with the damping member which exhibits cylindrical shape and is installed in the said extension part, and suppresses the vibration of the said motor.

  According to such a configuration, by making the motor shaft cylindrical, it is possible to reduce the weight of the motor shaft as compared with the case where the motor shaft is solid or the case where the recess for removing the meat is provided. Moreover, the vibration of the motor can be suppressed by installing the damping member in the extending portion.

  Moreover, it is preferable that the said damping member regulates the movement to the said other end side of the said 1st bearing because the said one end side contact | abuts to the said 1st bearing.

  According to such a configuration, one end of the damping member abuts on the first bearing, thereby restricting the movement of the first bearing to the other end, and as a result, the first bearing is prevented from dropping from the extending portion. Can be prevented.

  Moreover, it is preferable that the said damping member is an external columnar weight.

  According to such a configuration, the vibration of the motor can be suppressed by the outer columnar weight.

  The weight is preferably integral with the split case.

  According to such a configuration, the vibration of the motor can be suppressed by the damping member and the split case by integrating the weight with the split case. In addition, the number of parts of the motor structure can be reduced.

  The vibration damping member is preferably a dynamic damper.

  According to such a configuration, the vibration of the motor can be suppressed by the dynamic damper.

  The gear shaft is inserted into the motor shaft so that the spline coupling and the fitting are performed on the motor shaft, and the motor shaft is in contact with the one end side of the second bearing. It is preferable that a side contact portion is provided and the gear shaft has a gear side contact portion that contacts the other end side of the second bearing.

  According to such a configuration, the gear shaft has the gear-side contact portion that contacts the other end side of the second bearing. Therefore, an axial force acting on the gear shaft (force toward the second bearing) can be applied to the second bearing. The gear shaft is inserted inside the motor shaft, and the motor shaft has a motor side contact portion that contacts the one end side of the second bearing. Therefore, an axial force acting on the motor shaft (force toward the second bearing) can be applied to the second bearing. That is, since the axial force from the gear shaft does not act on the first bearing, the first bearing having a small load allowance can be used.

  ADVANTAGE OF THE INVENTION According to this invention, while aiming at simplification of a structure, the motor structure which suppresses the vibration of a motor can be provided.

1 is a system configuration diagram of a vehicle including a motor structure according to a first embodiment of the present invention. It is a longitudinal cross-sectional view of a motor structure. It is a longitudinal cross-sectional view which shows the assembly | attachment procedure of a motor structure. It is a longitudinal cross-sectional view which shows the assembly | attachment procedure of a motor structure. It is a longitudinal cross-sectional view of the motor structure which concerns on 2nd Embodiment of this invention. It is a longitudinal cross-sectional view of the motor structure which concerns on 3rd Embodiment of this invention.

<< First Embodiment >>
Prior to the description of the motor structure S (see FIG. 2) according to the present embodiment, the vehicle V including the motor structure S will be briefly described. A vehicle V shown in FIG. 1 is a parallel hybrid vehicle, and includes a motor 1, an engine 2, a transmission 3, an ISG 4 (Integrated Starter Generator), PDUs 51 and 52 (Power Drive Unit), and a battery B. It is equipped with.

The motor 1 is a first power source for rotating the drive wheels W, and is driven by AC power supplied via the PDU 51. In addition, at the time of regenerative braking, electric power is generated by the motor 1.
The engine 2 is a second power source for rotating the drive wheels W, and power is taken out by burning fuel.
The transmission 3 (power transmission device) is a device that transmits the power extracted from the motor 1 or the engine 2 to the drive shaft D at a predetermined gear ratio. In addition, although not shown in FIG. 1, the vehicle V includes a clutch that connects and disconnects the motor 1 and the transmission 3, a clutch that connects and disconnects the engine 2 and the transmission 3, and the like.

  The ISG 4 functions as a starter motor when the engine 2 is started by AC power input via the PDU 52. Further, the engine ECU (Electric Control Unit: not shown) drives the engine 2 in accordance with the remaining amount of the battery B, etc., so that the ISG 4 functions as a generator.

The PDU 51 includes an inverter, a converter, an ECU, and the like, converts DC power from the battery B into AC power, and drives the motor 1 with this AC power. Further, during regenerative braking, the generated power (AC power) of the motor 1 is converted to DC power by the PDU 51 and the battery B is charged.
The PDU 52 converts DC power from the battery B into AC power when the engine 2 is started, and drives the ISG 4 with this AC power. When the ISG 4 functions as a generator, the PDU 52 converts the generated power (AC power) of the ISG 4 into DC power and charges the battery B.
The battery B is a chargeable / dischargeable secondary battery, and is connected to the PDUs 51 and 52.

<Configuration of motor structure>
The motor structure S shown in FIG. 2 transmits power generated by the motor 1 to the transmission 3, or transmits power of the driving wheels W to the motor 1 (generator) via the transmission 3 during regenerative braking. To do.
The motor structure S includes a motor 1, a transmission 3, a first bearing 6a, a second bearing 6b, a third bearing 6c, a case body 7, a split case 8, and a bracket K. Yes.

(motor)
The motor 1 is an inner rotor type motor and is driven by AC power supplied from the PDU 51. The motor 1 includes a cylindrical rotor 11, a stator 12 disposed on the radially outer side of the rotor 11, and a cylindrical motor shaft 13 fixed to the inner peripheral surface of the rotor 11.

  The rotor 11 has a cylindrical shape as described above, and an insertion hole h1 into which the motor shaft 13 is inserted is formed on the central axis X thereof. A magnet (not shown) that generates an electromagnetic force (rotational force) with the stator 12 is embedded in the vicinity of the outer peripheral surface of the rotor 11.

  The stator 12 has a cylindrical shape and is disposed on the outer side in the radial direction of the rotor 11. Teeth (not shown) around which the wiring C is wound is formed on the inner peripheral surface side of the stator 12. Then, by supplying AC power from the PDU 51 via the wiring C, electromagnetic force is generated, and the rotor 11 rotates.

  The motor shaft 13 has a cylindrical shape and is fixed to the inner peripheral surface of the rotor 11. That is, the motor shaft 13 rotates together with the rotor 11. Further, both ends of the motor shaft 13 protrude from the rotor 11 in the axial direction. Thus, the 1st bearing 6a mentioned later is installed in the internal peripheral surface of the right end (one end) vicinity among the locations which protrude from the rotor 11, and the 2nd bearing mentioned later is provided in the outer peripheral surface near the left end (other end). 6b is installed.

The motor shaft 13 has a contact portion 13a that contacts the outer ring 61a of the first bearing 6a in the axial direction, a fitting portion 13b that engages with a gear shaft 311 described later, and an abutment that contacts the inner ring 62b of the second bearing 6b. A contact portion 13c and a coupling portion 13d that is spline coupled to the input gear 31 are provided.
The contact portion 13a extends radially inward from the inner peripheral surface near the right end of the motor shaft 13, and contacts the left wall surface of the outer ring 61a of the first bearing 6a. Thereby, the leftward movement of the first bearing 6a is restricted, and the first bearing 6a can be prevented from falling off.

The fitting portion 13 b is provided near the left end of the motor shaft 13 and is fitted with the gear shaft 311. That is, the fitting portion 311b of the gear shaft 311 is fitted inside the fitting portion 13b. Moreover, the 2nd bearing 6b is installed in the outer peripheral surface of the fitting part 13b.
The abutting portion 13c (motor side abutting portion) regulates the leftward movement of the motor shaft 13 by abutting against the second bearing 6b, and continues to the right side of the fitting portion 13b. The contact portion 13c has an outer diameter larger than the outer diameter of the fitting portion 13b, and is in contact with the right wall of the inner ring 62b of the second bearing 6b.

  The coupling portion 13d is provided on the right side of the left end of the motor shaft 13 with respect to the fitting portion 13b. A spline for spline coupling to the gear shaft 311 is formed on the inner peripheral wall of the coupling portion 13d. The spline has a configuration in which a plurality of teeth protruding inward in the radial direction and extending in the axial direction are provided in the circumferential direction.

(transmission)
The transmission 3 includes an input gear 31 and a counter gear 32 that meshes with the input gear 31.
The input gear 31 is a gear that transmits power from one of the motor 1 and the counter gear 32 to the other, and is installed on the left side of the motor 1. The input gear 31 includes a gear shaft 311 that is inserted into the motor shaft 13 and a meshing portion 312 that extends radially outward from the gear shaft 311 and meshes with the counter gear 32.

  The gear shaft 311 has a cylindrical shape (outer cylindrical shape), and the right side thereof is inserted into the motor shaft 13 and is arranged coaxially with the motor shaft 13. The gear shaft 311 contacts the contact portion 311a that contacts the second bearing 6b, the fitting portion 311b that fits the motor shaft 13, the coupling portion 311c that spline-couples to the motor shaft 13, and the third bearing 6c. A contact portion 311d.

The abutting portion 311a (gear side abutting portion) acts on the second bearing 6b to force the input gear 31 to move rightward, and extends radially outward from the outer peripheral surface of the gear shaft 311. . The contact portion 311a has an outer peripheral edge located outside the outer peripheral surface of the fitting portion 13b of the motor shaft 13, and is in contact with the left wall surface of the inner ring 62b of the second bearing 6b.
Note that the left end of the motor shaft 13 is slightly separated from the contact portion 311a of the input gear 31 in order to ensure that the contact portion 311a contacts the second bearing 6b.

  The fitting portion 311 b is continuous to the right side of the contact portion 311 a and is fitted inside the fitting portion 13 b of the motor shaft 13. The outer diameter of the fitting portion 311b is substantially equal to the inner diameter of the fitting portion 13b of the motor shaft 13, and the fitting portions 13b and 311b are close to each other in the radial direction. Thus, since the radial gap between the fitting portions 13b and 311b is very small, even if there is a slight gap in the radial direction with respect to the spline coupling of the coupling portions 13d and 311c, the motor shaft 13 and the gear shaft in the radial direction. The play of 311 can be eliminated and the vibration of the motor 1 can be prevented from being amplified.

The coupling portion 311c is provided near the right end of the gear shaft 311 and a spline for spline coupling with the motor shaft 13 is formed on the outer peripheral wall thereof. The spline has a configuration in which a plurality of teeth protruding in the radial direction and extending along the axial direction are provided in the circumferential direction. The input gear 31 rotates integrally with the motor shaft 13 by the spline connection between the coupling portion 311c of the gear shaft 311 and the coupling portion 13d of the motor shaft 13.
A disc-shaped cap F is installed at the right end of the input gear 31 to prevent the lubricating oil from entering the motor 1 side. The cap F is installed so as to close the opening on the right side of the input gear 31, and the vicinity of the outer periphery thereof is in contact with the inner wall surface of the motor shaft 13.

  The abutting portion 311d applies a force to the third bearing 6c to cause the input gear 31 to move to the left, and extends radially outward from the outer peripheral surface near the left end of the gear shaft 311. The contact portion 311d is in contact with the right wall surface of the inner ring 62c of the third bearing 6c. Note that a C-shaped shim E is provided between the contact portion 311d and the third bearing 6c in order to absorb the component tolerance in the axial direction.

  The meshing portion 312 is provided between the contact portion 311a and the contact portion 311d in the axial direction, and extends radially outward from the gear shaft 311. Gear teeth (for example, helical gears) that mesh with the counter gear 32 are formed on the outer peripheral surface of the meshing portion 312.

  When the meshing portion 312 is a helical gear, the gear teeth extend in an oblique direction with respect to the motor shaft 13, and therefore the axial direction with respect to the input gear 31 when the motor 1 is driven or during power generation (regeneration). The force of acts. For example, a rightward force acts on the input gear 31 when the motor 1 is driven, and a leftward force acts on the input gear 31 when the motor 1 generates power. When a rightward force acts on the input gear 31, a rightward force acts on the second bearing 6b from the contact portion 311a. On the other hand, when a leftward force is applied to the input gear 31, a leftward force is applied to the third bearing 6c from the contact portion 311d.

  The counter gear 32 is installed below the input gear 31 and meshes with the input gear 31. The counter gear 32 is rotatably supported by bearings R1 and R2.

(First bearing)
The first bearing 6a is interposed between the inner peripheral surface on the right end side of the motor shaft 13 in the radial direction and an extension portion 8a of the split case 8 described later, and rotatably supports the motor shaft 13. . Thus, by installing the first bearing 6 a on the inner peripheral surface of the motor shaft 13, the width of the motor structure S in the axial direction is reduced compared to the case where the bearing is installed on the outer peripheral surface of the motor shaft 13. be able to.

  The first bearing 6a includes an outer ring 61a, an inner ring 62a arranged on the radially inner side of the outer ring 61a, and a plurality of balls 63a arranged so as to be able to roll between the outer ring 61a and the inner ring 62a. Yes. The outer diameter of the first bearing 6 a is substantially equal to the inner diameter of the motor shaft 13, and the inner diameter of the first bearing 6 a is substantially equal to the diameter of the extending portion 8 a of the split case 8. The first bearing 6a is fixed to the inner peripheral surface of the motor shaft 13 by press fitting or the like. That is, as the motor shaft 13 rotates, the outer ring 61a of the first bearing 6a rotates. The outer ring 61a and the motor shaft 13 do not need to rotate integrally, and there may be slippage between them.

  The outer ring 61a of the first bearing 6a is in contact with the contact portion 13a of the motor shaft 13 as described above. Further, the inner ring 62 a of the first bearing 6 a is in contact with the contact portion 8 a of the split case 8. Thereby, the movement of the first bearing 6a in the axial direction is restricted, and the first bearing 6a can be prevented from falling off.

(Second bearing)
The second bearing 6b is fixed to the case body 7 and installed on the outer peripheral surface on the left end side of the motor shaft 13, and rotatably supports the motor shaft 13 and the input gear 31. In this way, by supporting the motor shaft 13 and the input gear 31 by the second bearing 6b, the vicinity of the left end of the motor shaft 13 and the vicinity of the right end of the gear shaft 311 are compared with the case where they are supported by separate bearings. The number of bearings can be reduced. The configuration of the second bearing 6b is the same as that of the first bearing 6a.

  The outer diameter of the second bearing 6b is set so that the second bearing 6b can be fitted and fixed to the second case member 72, and is fixed to the inner wall surface of the second case member 72 by press fitting or the like. The second bearing 6 b has an inner diameter that is substantially equal to the outer diameter of the motor shaft 13, and is installed on the outer peripheral surface of the fitting portion 13 b of the motor shaft 13. That is, the inner ring 62b of the second bearing 6b rotates with the rotation of the motor shaft 13.

  As described above, the second bearing 6b is installed on the outer peripheral surface of the fitting portion 13b of the motor shaft 13, and the fitting portions 13b and 311b are fitted to each other. Therefore, the relative position between the motor shaft 13 and the input gear 31 is firmly fixed in the radial direction by the second bearing 6b fixed to the case body 7 and the fitting portions 13b and 311b. Can be suppressed.

(Third bearing)
The third bearing 6c is fixed to the case body 7 and is installed on the outer peripheral surface on the left end side of the input gear 31, and rotatably supports the input gear 31. As shown in FIG. 2, the input gear 31 is supported by both ends by the second bearing 6b and the third bearing 6c, so that the radial direction of the input gear 31 can be compared to the case where the third bearing 6c is cantilevered. Can be suppressed. The configuration of the third bearing 6c is the same as that of the first bearing 6a.

  The third bearing 6c has an outer diameter so that it can be fitted and fixed to the third case member 73, and is fixed to the inner wall surface of the third case member 73 by press fitting or the like. The third bearing 6 c has an inner diameter that is substantially equal to the outer diameter of the gear shaft 311 and is installed on the outer peripheral surface of the gear shaft 311. That is, as the input gear 31 rotates, the inner ring 62c of the third bearing 6c rotates.

(Case body)
The case body 7 is a metal member that houses the motor 1 and the transmission 3, and includes a first case member 71, a second case member 72, and a third case member 73.
The 1st case member 71 is a case which accommodates the motor 1 with the 2nd case member 72 mentioned later, and is exhibiting the bottomed cylindrical shape. In the right wall (bottom wall) of the first case member 71, a circular hole h <b> 2 for installing a divided case 8 to be described later is formed at a location corresponding to the central axis X of the motor 1. The first case member 71 is provided with a plurality of insertion holes h3 for bolts M for fixing the divided case 8 so as to surround the hole h2.

  The second case member 72 is a case that houses the motor 1 together with the first case member 71 and houses the transmission 3 together with the third case member 73 described later. A hole h4 for penetrating the motor shaft 13 is formed at a location corresponding to the central axis X of the motor 1 in the second case member 72.

  An annular seal member G is installed between the peripheral surface of the hole h4 and the outer peripheral surface of the motor shaft 13 in the radial direction. The seal member G is bonded to the peripheral surface of the hole h4 and is in sliding contact with the motor shaft 13. That is, the internal space of the case body 7 is partitioned into the motor 1 side and the transmission 3 side by the second case member 72 and the seal member G. This can prevent the lubricating oil on the transmission 3 side from entering the motor 1 side.

  The second case member 72 has a contact portion 72a that contacts the right wall surface of the outer ring 61b of the second bearing 6b. The rightward force from the input gear 31 acts on the contact portion 72a of the second case member 72 via the contact portion 311a and the second bearing 6b. The second case member 72 is provided with bearings R1 and R2 for rotatably supporting the counter gear 32.

  The third case member 73 is a case that houses the transmission 3 together with the second case member 72. The third case member 73 is provided with a third bearing 6c and bearings R1 and R2 for pivotally supporting the counter gear 32.

(Split case)
The divided case 8 is a member for rotatably supporting the first bearing 6a installed on the inner peripheral surface of the motor shaft 13, and is fixed to the first case member 71 with the hole h2 closed from the inside. Has been. The split case 8 has an extending portion 8a that faces the inside of the motor shaft 13, a contact portion 8b that contacts the inner ring 62a of the first bearing 6a, and a fastening portion 8c that is fastened to the first case member 71. doing.
The extending portion 8 a has a cylindrical shape and faces the inside of the motor shaft 13 in a state where the divided case 8 is fixed to the first case member 71. The 1st bearing 6a is installed in the outer peripheral surface of this extension part 8a.

The contact portion 8b is connected to the right side of the extension portion 8a and extends outward in the radial direction. The contact portion 8b is in contact with the right wall surface of the inner ring 62a of the first bearing 6a.
The fastening portion 8c is connected to the right side of the contact portion 8b and extends radially outward. A plurality of insertion holes h5 through which the bolts M are inserted are formed in the fastening portion 8c. The bolt M is inserted through the insertion hole h <b> 3 of the first case member 71 and the insertion hole h <b> 5 of the divided case 8, and the head thereof is in contact with the outer wall surface of the first case member 71. By installing the bolt M in this way, the divided case 8 is fixed to the case body 7.

(bracket)
The bracket K is a member for fixing the case body 7 in which the motor 1 and the transmission 3 and the like are accommodated to the vehicle body. In the example shown in FIG. 2, a bracket K is fixed to the upper side of the right wall of the case body 7.

<Motor assembly procedure>
As shown in FIG. 3A, the motor shaft 13 fixed to the rotor 11 and the divided case 8 attached to the motor shaft 13 are supported while being pressed from the left and right by spindles P1 and P2. A first bearing 6 a is installed between the inner peripheral surface near the right end of the motor shaft 13 in the radial direction and the split case 8.
A taper surface q1 is formed at the opening edge on the left side of the motor shaft 13 so as to correspond to the shape near the tip of the spindle P1 and the diameter decreases toward the right side. Similarly, a tapered surface q2 corresponding to the shape near the tip of the spindle P2 is also formed on the divided case 8. As shown in FIG. 3A, the vicinity of the tip of the spindle P1 is in contact with the taper surface q1 of the motor shaft 13, and the vicinity of the tip of the spindle P2 is in contact with the taper surface q2 of the split case 8.

  Although not shown in FIG. 3A, the spindle P1 is passed through the hole h4 of the second case member 72 (see FIG. 3B) before being pressed by the spindles P1 and P2. The spindle P2 is passed through the hole h2 of one case member 71 (see FIG. 4A).

  Next, as shown in FIG. 3B, the second case member 72 on which the second bearing 6 b and the seal member G are installed is assembled to the motor shaft 13 from the left side. That is, the inner peripheral surface of the second bearing 6b is slid with respect to the outer peripheral surface of the fitting portion 13b of the motor shaft 13, and the inner ring 62b of the second bearing 6b is in contact with the contact portion 13c of the motor shaft 13. Let

  Next, as shown in FIG. 4A, a positioning stud bolt N is attached to the insertion hole h5 of the split case 8, and the first case member 71 on which the stator 12 and the like are installed is moved from the right side to the motor shaft 13. Assemble. A centering guide jig J is installed so as to close the hole h2 of the first case member 71 from the outside. The centering guide jig J has a plurality of holes h6 through which the stud bolts N are inserted.

By inserting the stud bolt N into the hole h3 of the first case member 71 and the hole h6 of the centering guide jig J, the rotor 11 and the stator 12 can be arranged coaxially. Although a magnet (not shown) embedded in the rotor 11 has a strong magnetic force, the use of the stud bolt N and the centering guide jig J keeps the rotor 11 and the stator 12 coaxial. The assembly work can be performed.
As shown in FIG. 4A, the first case member 71 is assembled from the right side, and the fastening portion 8c of the divided case 8 is brought into contact with the first case member 71 (around the hole h2).

  Next, as shown in FIG. 4B, the spindles P1 and P2, the stud bolt N (see FIG. 4A), and the centering guide jig J (see FIG. 4A) are removed, and the insertion hole The bolt M is attached via h3 and h5. Further, a third case member 73 (see FIG. 2) on which the input gear 31, counter gear 32, third bearing 6c and the like are installed is assembled from the left side of the motor 1, and a bracket K (see FIG. 2) is assembled from the right side of the motor 1. The motor structure S is completed by assembling (see FIG. 2).

<Effect>
According to the present embodiment, the first bearing 6 a is installed on the inner peripheral surface of the motor shaft 13, so that the axial width of the motor structure S compared to the case where the bearing is installed on the outer peripheral surface of the motor shaft 13. Can be made smaller and more compact.
Moreover, by making the motor shaft 13 cylindrical, the weight of the motor shaft 13 can be reduced as compared with a case where the motor shaft 13 is solid or a case where a recess for removing the meat is provided. Similarly, weight reduction of the gear shaft 311 can be achieved by making the gear shaft 311 cylindrical.

The input gear 31 generates a force that causes the input gear 31 to move in the axial direction and the radial direction as the motor 1 is driven or generates power (regeneration). As described above, since the contact portion 311a of the input gear 31 contacts the second bearing 6b and the contact portion 311d contacts the third bearing 6c, the axial force from the input gear 31 is the second. It acts on the bearing 6b and the third bearing 6c.
Further, the second bearing 6 b is installed on the radially outer side of the fitting portions 13 b and 311 b that are fitted to each other, and the second bearing 6 b is fixed to the second case member 72. A third bearing 6 c is installed on the outer peripheral surface of the gear shaft 311, and the third bearing 6 c is fixed to the third case member 73. Therefore, the radial force from the input gear 31 also acts on the second bearing 6b and the third bearing 6c.

  Thus, the radial / axial force from the input gear 31 acts on the second bearing 6b and the third bearing 6c, and does not act on the first bearing 6a. Accordingly, the first bearing 6a having a small allowable load can be used. That is, the first bearing 6a can be reduced in size, and the manufacturing cost of the motor structure S can be reduced.

  Further, the fitting portion 13b of the motor shaft 13 and the fitting portion 311b of the gear shaft 311 are very close to each other in the radial direction, and the second bearing 6b is installed on the outer peripheral surface of the fitting portion 13b. . Therefore, the relative position between the motor shaft 13 and the input gear 31 is firmly fixed in the radial direction by the second bearing 6b fixed to the case body 7 and the fitting portions 13b and 311b. The backlash of the shaft 311 can be eliminated and the motor 1 can be prevented from being amplified.

  Moreover, the left side of the motor shaft 13 and the right side of the input gear 31 are pivotally supported by the second bearing 6b. Therefore, the number of bearings can be reduced as compared with the case where the left side of the motor shaft 13 and the right side of the input gear 31 are axially supported by separate bearings, and the motor structure S can be simplified.

Further, the right side of the input gear 31 is pivotally supported by the second bearing 6b, and the left side of the input gear 31 is pivotally supported by the third bearing 6c. Thus, by supporting the input gear 31 with both ends, the radial deflection of the input gear 31 can be suppressed.
Furthermore, by providing the divided case 8 fixed to the first case member 71 in a state where the hole h2 is closed, it can be pressed from both sides in the axial direction using the spindles P1 and P2 during the assembling work. Therefore, the assembling work when the rotor 11 and the stator 12 are installed on the same axis can be appropriately performed.

Second Embodiment
The second embodiment is different from the first embodiment in that the shape of the divided case 8A (see FIG. 5) is different from the first embodiment, but the first embodiment is different in configuration from the first embodiment. It is the same. Therefore, a different part from 1st Embodiment is demonstrated and description is abbreviate | omitted about the overlapping part.

  As shown in FIG. 5, the divided case 8 </ b> A includes an extended portion 8 a that faces the inside of the motor shaft 13, a contact portion 8 b that contacts the first bearing 6 a, and a fastening portion 8 c that is fastened to the first case member 71. And have. The divided case 8 </ b> A is a rotating body formed corresponding to the hole h <b> 2 of the first case member 71 and is fixed to the first case member 71 by a bolt M. In addition, it is preferable to use a relatively large specific gravity (for example, iron) as the divided case 8A. Accordingly, the divided case 8A also functions as a weight (mass weight), and a weight suitable for suppressing vibration of the motor 1 together with the weight 91 described later can be secured.

The extending portion 8a has a cylindrical shape, and the tip (left end) extends to the left side of the first bearing 6a. Near the base end (right end) of the extending portion 8a, a first bearing 6a is installed. In addition, the distal end side (left side) of the extending portion 8a is formed with a smaller diameter than the proximal end side (right side), and a slight gap in the axial direction is formed between the step surface and the right end surface of the weight 91. Q is provided.
The contact portion 8b is connected to the right side of the extension portion 8a and extends outward in the radial direction. The contact portion 8b is in contact with the right wall surface of the inner ring 62a of the first bearing 6a.
The fastening portion 8c is connected to the right side of the contact portion 8b and extends radially outward. A plurality of insertion holes h5 through which the bolts M are inserted are formed in the fastening portion 8c.

  The weight 91 (damping member) is an outer cylindrical metal member (for example, iron) that suppresses vibration in the radial direction of the motor 1. A concave portion u1 corresponding to the shape of the extending portion 8a of the divided case 8A is formed on the right end surface of the weight 91. The extension part 8a of the split case 8A is shrink-fitted or press-fitted into the concave part u1, whereby the weight 91 is fixed to the split case 8A. Further, the split case 8 </ b> A and the weight 91 are substantially coaxial with the central axis X of the motor 1 in a state where the extending portion 8 a is fitted on the inner peripheral surface of the first bearing 6 a.

  The vibration of the stator 12 propagates to the weight 91 through the first case member 71 and the divided case 8A. Further, the mass and the like of the weight 91 are set so that the natural frequency of the entire motor structure S exceeds the audible range. Therefore, the natural frequency of the motor structure S can be adjusted by the weight 91 and the vibration of the motor structure S can be suppressed.

  Further, the weight 91 is in contact with the left wall surface of the inner ring 62a of the first bearing 6a. In order to bring the weight 91 into contact with the inner ring 62a in this way, as described above, the gap Q in the axial direction is provided between the weight 91 and the extending portion 8a. Thereby, the leftward movement of the first bearing 6a can be restricted. That is, the weight 91 suppresses vibrations in the radial direction of the stator 12 and also functions to prevent the first bearing 6a from being pulled out and to prevent the first bearing 6a from slipping.

<Effect>
According to the present embodiment, the vibration of the motor 1 can be suppressed by the weight 91 fixed to the divided case 8A. In addition, by appropriately setting the mass of the weight 91, the natural frequency of the motor structure S can be adjusted to exceed the audible range, for example. Therefore, it is possible to prevent a sound that is harsh to the occupant as the motor 1 is driven.
Further, by causing the weight 91 to contact the inner ring 62a of the first bearing 6a, it is possible to prevent the first bearing 6a from dropping off and to prevent wear due to sliding (creep phenomenon) of the inner ring 6a.

<Third Embodiment>
The third embodiment is different from the second embodiment in that the shape of the split case 8B (see FIG. 6) is different and that the dynamic damper 92 is provided instead of the weight 91 (see FIG. 5). The configuration is the same as in the second embodiment. Therefore, a different part from 2nd Embodiment is demonstrated and description is abbreviate | omitted about the overlapping part.

  The split case 8B shown in FIG. 6 has the same configuration as the split case 8A (see FIG. 5) described in the second embodiment, except that the diameter of the extending portion 8a is reduced in order to install the dynamic damper 92. It has become.

  The dynamic damper 92 (damping member) has a cylindrical outer shape and is arranged coaxially with the central axis X of the motor 1. The dynamic damper 92 includes a collar 92a, an elastic body 92b installed on the radially outer side of the collar 92a, and a metal member 92c installed on the radially outer side of the elastic body 92b.

  The collar 92a has a relatively thin cylindrical shape, and is fixed to the outer peripheral surface of the divided case 8B. The collar 92a has a contact portion 921a near the right end thereof. The contact portion 921a extends radially outward, and the vicinity of the outer peripheral edge thereof is in contact with the left wall surface of the inner ring 62a of the first bearing 6a. Further, the distal end side (left side) of the extending portion 8a is formed to have a smaller diameter than the proximal end side (right side), and a slight gap Q between the stepped surface and the contact portion 921a in the axial direction. Is provided. In other words, the leftward movement of the first bearing 6a is restricted by the contact portion 921a, and the first bearing 6a is prevented from being pulled out and the first bearing 6a is prevented from idling.

The elastic body 92b is installed on the outer peripheral surface of the collar 92a and has a cylindrical shape. The elastic body 92b has a function of attenuating vibration of the motor structure S and adjusting a natural frequency of the motor structure S together with a metal member 92c described later.
The metal member 92c is installed on the outer peripheral surface of the elastic body 92b and has a cylindrical shape. In order to secure a weight suitable for suppressing vibration, it is preferable to use a material having a relatively large specific gravity (for example, iron) as a material constituting the metal member 92c. The collar 92a, the elastic body 92b, and the metal member 92c are substantially integrated.

<Effect>
According to the present embodiment, the natural frequency of the motor structure S can be adjusted to exceed the audible range, for example, by appropriately setting the mass of the metal member 92c included in the dynamic damper 92. Further, the vibration in the radial direction of the motor 1 can be attenuated by the dynamic damper 92, and the vibration of the motor 1 can be effectively suppressed.
Further, since the contact portion 921a of the dynamic damper 92 contacts the inner ring 62a of the first bearing 6a, it is possible to prevent the first bearing 6a from dropping off and to prevent wear due to sliding (creep phenomenon) of the inner ring 6a.

≪Modification≫
As mentioned above, although each embodiment demonstrated the motor structure S which concerns on this invention, this invention is not limited to these description, A various change can be made.
For example, in each embodiment, the gear shaft 311 is inserted into the motor shaft 13, and the fitting portion 311 b and the coupling portion 311 c of the gear shaft 311 are disposed radially inward from the fitting portion 13 b and the coupling portion 13 d of the motor shaft 13. However, the motor shaft 13 may be inserted into the gear shaft 311. That is, the outer peripheral wall of the motor shaft 13 is splined to the inner peripheral wall of the gear shaft 311, and the portion of the motor shaft 13 corresponding to the second bearing 6 b in the axial direction is fitted inside the gear shaft 311. Good.
Even in this case, the contact portion 311a of the gear shaft 311 contacts the left wall of the inner ring 62b of the second bearing 6b, and the contact portion 72a of the case body 7 contacts the right wall of the outer ring 61b of the second bearing 6b. (See FIG. 2), the axial and radial forces from the input gear 31 can be applied to the second bearing 6b.

  In the second embodiment, the case where the split case 8A (see FIG. 5) and the weight 91 are separate has been described. However, the split case 8A and the weight 91 may be integrated. Thereby, the number of parts of the motor structure S can be reduced and vibration of the motor 1 can be suppressed. If the weight 91 is omitted from the configuration shown in FIG. 5 and the divided case 8A is made of a metal having a relatively large specific gravity (for example, iron), the divided case 8A can function as a weight.

  Moreover, although each embodiment demonstrated the case where the motor shaft 13 (refer FIG. 2) exhibited cylindrical shape, it is not restricted to this. In other words, the motor shaft 13 only needs to have a cylindrical shape, and for example, recesses may be provided at both ends corresponding to the installation locations of the split case 8 and the gear shaft 311.

Moreover, although each embodiment demonstrated the case where the input gear 31 was a helical gear, it is not restricted to this. That is, another type of gear such as a parallel gear or a planetary gear may be used as the input gear 31.
Moreover, although each embodiment demonstrated the case where the 1st bearing 6a, the 2nd bearing 6b, and the 3rd bearing 6c were ball bearings, you may use other types of bearings, such as a roller bearing.

In the second embodiment, the configuration in which the right end surface of the weight 91 (see FIG. 5) is in contact with the inner ring 62a of the first bearing 6a has been described. However, even if the weight 91 is separated from the first bearing 6a. Good. Even in this case, the first bearing 6 a can be prevented from being pulled out by the contact portion 13 a of the motor shaft 13. Similarly, the contact portion 921a may be omitted from the dynamic damper 92 in the third embodiment.
Moreover, although 2nd Embodiment demonstrated the case where the external shape of the weight 91 (refer FIG. 5) was cylindrical shape, it does not restrict to this. For example, the weight 91 may be a hexagonal column or octagonal column.

  Moreover, although each embodiment demonstrated the case where the motor structure S was mounted in a parallel type hybrid vehicle, it is not restricted to this. For example, you may mount in other types of vehicles, such as a series type hybrid vehicle, an electric vehicle, and a fuel cell vehicle. In addition to the four-wheeled vehicle, the motor structure S may be installed in a moving body such as a two-wheeled vehicle or a three-wheeled vehicle, or in a stationary system.

S motor structure 1 motor 11 rotor 12 stator 13 motor shaft 13a contact portion 13b fitting portion 13c contact portion (motor side contact portion)
13d coupling part 3 transmission (power transmission device)
31 Input gear 311 Gear shaft 311a Contact part (gear side contact part)
311b Fitting part 311c Coupling part 311d Contact part 6a First bearing 6b Second bearing 6c Third bearing 61a, 61b, 61c Outer ring 62a, 62b, 62c Inner ring 7 Case body 8, 8A, 8B Divided case 8a Extension part 8b Contact part 8c Fastening part 91 Weight (vibration control member)
92 Dynamic damper (damping member)
32 Counter gear X Center axis h2 hole

Claims (7)

A motor having a cylindrical rotor, a stator disposed on the radially outer side of the rotor, and an outer cylindrical motor shaft fixed to an inner peripheral surface of the rotor;
A power transmission device that has an outer cylindrical gear shaft that rotates integrally with the motor shaft, and that transmits power to and from the rotor;
A case main body that houses the motor and the power transmission device, and has a hole formed on one end side on the central axis of the motor;
A split case that has an extending portion facing the inside of the one end side of the motor shaft and is fixed to the case body in a state in which the hole is closed;
A first bearing that is interposed between the inner peripheral surface of the one end side of the motor shaft in the radial direction and the extending portion, and rotatably supports the motor shaft;
A second bearing fixed to the case body and installed on the other end side of the motor shaft, and rotatably supporting the motor shaft and the gear shaft;
A third bearing fixed to the case body and installed on the other end side of the gear shaft, and rotatably supporting the gear shaft;
The one end of the gear shaft is splined to the motor shaft,
A portion of the gear shaft that corresponds to the second bearing in the axial direction is fitted to the motor shaft. The motor shaft has a cylindrical shape,
The motor structure according to claim 1, further comprising a damping member that is installed in the extending portion and suppresses vibration of the motor. The damping member is
3. The motor structure according to claim 2, wherein movement of the first bearing toward the other end side is restricted by the one end side coming into contact with the first bearing. 4. The motor structure according to claim 2, wherein the vibration damping member is an external columnar weight. 5. The motor structure according to claim 4, wherein the weight is integral with the split case. The motor structure according to claim 2 or 3, wherein the vibration damping member is a dynamic damper. The gear shaft is inserted inside the motor shaft, so that the spline coupling and the fitting to the motor shaft,
The motor shaft is
A motor-side contact portion that contacts the one end side of the second bearing;
The gear shaft is
The motor structure according to any one of claims 1 to 6, further comprising a gear side contact portion that contacts the other end side of the second bearing.

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