JP2019059287A - In-wheel motor driving device - Google Patents

Abstract

To provide an in-wheel motor driving device in which, even if a gear shaft mounting hole of a casing is eccentric from a regular position due to machining error, the eccentricity is corrected and the gear shaft can be mounted without eccentricity.SOLUTION: In a space between an outer diameter of a rolling bearing 49 supporting a gear shaft 36 and an inner diameter of a bearing fitting hole 73b in which the rolling bearing 49 is fitted, there are arranged an outside eccentric ring 82 in which an inner diameter is eccentric with respect to an outer diameter and an outer diameter can be turned in a range of 360° with respect to an inner diameter of a gear shaft mounting hole 73b; and an inside eccentric ring 81 in which the size of an outer diameter is the same size as the inner diameter of the outside eccentric ring 82, and an inner diameter is eccentric with respect to the outer diameter, and which can turn in the range of 360° with respect to the inner diameter of the outside eccentric ring 82. The outside eccentric ring 82 and the inside eccentric ring 81 are each relatively rotated in the range of 360°, and accordingly a shaft center of the gear shaft 36 inserted and fixed in the inner diameter of the inside eccentric ring 81 is made movable.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an in-wheel motor drive device, in particular, a gear in which both ends of a gear shaft constituting a reduction gear unit for decelerating and outputting rotation of an electric motor unit are formed on an inner wall surface of a casing accommodating the reduction gear unit. When arranged in the shaft mounting hole, even if the position of the gear shaft mounting hole in the casing is eccentric from the normal position due to processing error, the eccentricity is eliminated and the gear shaft can be mounted without eccentricity The present invention relates to a motor drive device.

  Since the in-wheel motor drive is housed inside the wheel, it becomes the unsprung weight of the vehicle. Since the increase in unsprung weight deteriorates the ride quality of the vehicle, reducing the size and weight of the in-wheel motor drive is an important requirement. Since the output torque of the electric motor is proportional to the size and weight of the electric motor, a large motor is required to generate the torque necessary for driving the vehicle by the motor alone. Therefore, a means to miniaturize is used by using an electric motor in combination with a reduction gear (Patent Document 1, Patent Document 2).

  For example, as shown in FIG. 11, the in-wheel motor drive device 121 includes an electric motor unit A that generates a driving force, a reduction gear unit B that decelerates and outputs the rotation of the electric motor unit A, and a reduction gear unit B And a wheel bearing C for transmitting an output from the vehicle to a rear wheel as a drive wheel.

  The reduction gear portion B is composed of a plurality of gear shafts and is accommodated in a casing 122. In the in-wheel motor drive device 121 shown in FIG. 11, the reduction gear unit B includes an input shaft 130 having an input gear 130a, an intermediate shaft 131 having an input intermediate gear 131a and an output intermediate gear 131b, and a final output gear 132a. And an output shaft 132 provided with a parallel gear reducer.

  The input shaft 130, the intermediate shaft 131, and the output shaft 132 are disposed in parallel to one another. The input shaft 130 is supported by rolling bearings 142 and 143, the intermediate shaft 131 is supported by rolling bearings 144 and 145, and the output shaft 132 is supported by rolling bearings 148 and 149, respectively. .

  More specifically, the end on the inboard side of the input shaft 130 is rotatably supported via the rolling bearing 142 in the gear shaft attachment hole 171a machined in the inner wall surface of the casing 122, and on the outboard side An end portion is rotatably supported via a rolling bearing 143 in a gear shaft attachment hole 171 b formed in the inner wall surface of the casing 122.

  The intermediate shaft 131 has its inboard end rotatably supported via the rolling bearing 44 in the gear shaft attachment hole 172a machined in the inner wall surface of the casing 122, and the outboard end is It is rotatably supported via a rolling bearing 145 in a gear shaft attachment hole 172b machined in the inner wall surface of the casing 122.

  In the output shaft 132, the inboard end is rotatably supported via a rolling bearing 148 in a gear shaft attachment hole 173a machined in the inner wall surface of the casing 122, and the outboard end is It is rotatably supported via a rolling bearing 149 in a gear shaft attachment hole 173 b machined in the inner wall surface of the casing 122.

JP, 2013-32139, A JP, 2015-120401, A

  The gear shaft mounting holes 171a, 171b, 172a, 172b, 173a, 173b disposed on the inner wall surface of the casing 122 of the reduction gear portion B are machined by a machining center.

  The tolerance width of the hole diameters of the gear shaft attachment holes 171a, 171b, 172a, 172b, 173a and 173b is IT6 to 7 (about 30 μm), but using a boring head or the like that can be finely adjusted in the radial direction It is possible to satisfy dimensional tolerances if the machine tool rotational accuracy is maintained.

  On the other hand, the positional accuracy of the gear shaft mounting holes 171a, 171b, 172a, 172b, 173a, 173b disposed on the inner wall surface of the casing 122 of the reduction gear portion B is the positioning accuracy when the machine tool moves the head Many error factors such as deformation at the time of chucking of the case which is the workpiece, thermal expansion of the workpiece and the machine tool due to environmental temperature change must be taken into consideration. Tolerance of the

  If the gear shaft mounting holes 171a, 171b, 172a, 172b, 173a, 173b are eccentric from the normal mounting position on the inner wall surface of the casing 122 of the reduction gear unit B due to processing errors, the gear shaft mounting holes 171a, 171b, 172a, 172b The shaft center of the gear shaft inserted and fixed to the bearings 173a, 173b via the rolling bearings 142, 143, 144, 145, 148, 149 is also decentered from the correct position, and the gear life of the reduction gear portion B, It will affect the sound vibration.

For example, as shown in FIG. 12, the center of the gear shaft mounting hole 173b of the insert fixed end of the outboard side of the output shaft 132 is, the position of the O ₂ showing the center O ₁ by the dashed line in the normal position by the machining error When the eccentricity up to a is made, the center of the output shaft 132 inserted and fixed in the gear shaft attachment hole 173b is also eccentric at the position of O ₂ shown by a dashed dotted line.

  In order not to affect the life of the gears of the reduction gear portion B and the sound and vibration, it is preferable to keep the positional accuracy of the gear shaft mounting holes 171a, 171b, 172a, 172b, 173a, 173b as small as possible. It is difficult to secure stable position accuracy in mass production because of the following reasons.

  Therefore, the present invention provides an in-wheel motor drive device capable of correcting the eccentricity and mounting the gear shaft without eccentricity, even if the gear shaft mounting hole of the casing is eccentric from the normal position due to processing error It is something to try.

  In order to solve the above-described problems, the present invention transmits an output from an electric motor unit that generates a driving force, a reduction gear unit that decelerates and outputs rotation of the electric motor unit, and a reduction gear unit to wheels. And a bearing unit for wheels, wherein the reduction gear unit comprises a plurality of gear shafts housed in a casing, and both end portions of the respective gear shafts are formed in gear shaft mounting holes formed in opposing inner wall surfaces of the casing. In the in-wheel motor drive device rotatably supported via a rolling bearing, the inner diameter is eccentric to the outer diameter between the outer diameter of the rolling bearing and the inner diameter of the gear shaft mounting hole, and the outer diameter Has an outer eccentric ring rotatable relative to the inner diameter of the gear shaft mounting hole, and an outer diameter equal in size to the inner diameter of the outer eccentric ring, eccentric to the outer diameter, Inner eccentric ring rotatable relative to the inner diameter of the eccentric ring And the outer eccentric ring and the inner eccentric ring are respectively rotated relative to each other to form a circle having a radius twice the amount of eccentricity of the inner diameter with respect to the outer diameter of the outer eccentric ring and the inner eccentric ring. It is characterized in that the axial center of the gear shaft inserted and fixed to the inner diameter of the inner eccentric ring is made movable at any point in the inside.

  As described above, according to the present invention, a range of 360 ° with the inner diameter of the gear shaft mounting hole between the inner diameter of the gear shaft mounting hole formed on the opposing inner wall surface of the casing and the outer diameter of the rolling bearing It has an outer eccentric ring that can rotate inside and an outer diameter that is the same size as the inner diameter of the outer eccentric ring, eccentric to the outer diameter, and 360 to the inner diameter of the outer eccentric ring An outer eccentric ring and an inner eccentric are arranged by arranging an inner eccentric ring rotatable within the range of ° and relatively rotating the outer eccentric ring and the inner eccentric ring within the range of 360 ° respectively. The axial center of the gear shaft inserted and fixed to the inner diameter of the inner eccentric ring is movable at any point in a circle whose radius is twice the eccentricity of the inner diameter with respect to the outer diameter of each of the core rings be able to. The relative value of the eccentricity of the inner diameter to the outer diameter of each of the two eccentric rings, ie, the outer eccentric ring and the inner eccentric ring, can be managed with high accuracy at a few μm level, so high precision processing If the positioning accuracy of the gear shaft mounting hole with difficulty is to be managed within the error with the radius of twice the eccentricity of the inner diameter to the outer diameter of each of the outer eccentric ring and the inner eccentric ring as the radius Even if the gear shaft mounting hole is misaligned, the shaft center of the rolling bearing supporting the end of the gear shaft can be corrected to the correct position and placed in the bearing fitting hole.

  Therefore, according to the present invention, it is possible to correct the misalignment of the gear shaft constituting the reduction gear portion, and to realize the long life of the device and the reduction of the sound and vibration.

It is a longitudinal section of the in-wheel motor drive concerning one embodiment of this invention. It is a cross-sectional view of the in-wheel motor drive device of FIG. 1 which was arrowed by the II-II line of FIG. It is a disassembled cross-sectional view of the in-wheel motor drive of FIG. 1 which shows the eccentricity correction mechanism using two eccentric rings of the in-wheel motor drive which concerns on one Embodiment of this invention. It is a disassembled cross-sectional view of the in-wheel motor drive device of FIG. 1 which corrected eccentricity of the rolling bearing using two eccentric rings. FIG. 2 is a cross-sectional view of the in-wheel motor drive of FIG. 1 that corrects for eccentricity using a positioning jig. It is a front view of the positioning jig of FIG. It is a cross-sectional view of the in-wheel motor drive device of FIG. 1 which shows the state which fitted two eccentric rings with the positioning jig of FIG. It is a cross-sectional view of the in-wheel motor drive device of FIG. 1 which shows the state which correct | amends eccentricity by the positioning jig which fitted two eccentric ring of FIG. It is a top view which shows schematic structure of the electric vehicle carrying an in-wheel motor drive device. FIG. 10 is a rear sectional view showing the electric vehicle of FIG. 9; It is a longitudinal cross-sectional view of the in-wheel motor drive device of a prior art example. It is a cross-sectional view of the in-wheel motor drive device which was arrowed by the XII-XII line of FIG.

  First, an electric vehicle equipped with an in-wheel motor drive device according to an embodiment of the present invention will be described based on FIGS. 9 and 10. FIG. 9 is a schematic plan view of the electric vehicle 11 equipped with the in-wheel motor drive device 21, and FIG. 10 is a schematic cross-sectional view of the electric vehicle 11 viewed from the rear.

  As shown in FIG. 9, the electric vehicle 11 includes a chassis 12, a front wheel 13 as a steered wheel, a rear wheel 14 as a drive wheel, and an in-wheel motor drive device 21 for transmitting a driving force to the rear wheel 14. Equip. The rear wheel 14 is housed inside the wheel housing 15 of the chassis 12 and fixed to the lower part of the chassis 12 via a suspension system 16 as shown in FIG.

  The suspension device 16 supports the rear wheel 14 by suspension arms extending leftward and right, and absorbs a vibration that the rear wheel 14 receives from the ground and suppresses a vibration of the chassis 12 by a strut including a coil spring and a shock absorber. A stabilizer that suppresses the inclination of the vehicle body at the time of turning or the like is provided at the connection portion of the left and right suspension arms. The suspension device 16 is of an independent suspension type in which the left and right wheels are independently moved up and down in order to improve the followability to the unevenness of the road surface and efficiently transmit the driving force of the rear wheel 14 to the road surface.

  The electric vehicle 11 eliminates the need to provide a motor, a drive shaft, a differential gear mechanism, etc. on the chassis 12 by providing in-wheel motor drive devices 21 for driving the left and right rear wheels 14 inside the wheel housing 15 Therefore, the cabin space can be widely secured, and the rotation of the left and right rear wheels 14 can be controlled, respectively.

  Before describing the characteristic configuration of the embodiment of the present invention, the overall configuration of the in-wheel motor drive device 21 will be described based on FIGS. 1 and 2. In the following description, in a state where the in-wheel motor drive device 21 is mounted on a vehicle, the side closer to the outside of the vehicle is referred to as the outboard side, and the side closer to the center is referred to as the inboard side.

  As shown in FIG. 1, the in-wheel motor drive device 21 includes an electric motor unit A that generates a driving force, a reduction gear unit B that decelerates and outputs the rotation of the electric motor unit A, and a reduction gear unit B And a wheel bearing C for transmitting an output to a rear wheel as a drive wheel. The electric motor unit A, the reduction gear unit B, and the wheel bearing unit C are accommodated or attached to the casing 22 respectively. The casing 22 may have a single-piece structure as well as a separable structure. The casing 22 is preferably made of a light metal such as aluminum or aluminum alloy. In particular, since the aluminum alloy is light in weight and high in strength, the casing 22 of this embodiment is made of an aluminum alloy.

The electric motor unit A includes a stator 23 fixed to the casing 22, a rotor 24 disposed so as to face the radially inner side of the stator 23 with a gap, and a radially inner side of the rotor 24 and is integral with the rotor 24. It is comprised by the radial gap type electric motor 26 provided with the motor rotating shaft 25 which rotates. The motor rotation shaft 25 can rotate at a high speed of about ten thousand and several thousand revolutions per minute. The stator 23 is configured by winding a coil around a magnetic core, and the rotor 24 is configured by a permanent magnet or the like.
The electric motor 26 can also be applied to an axial gap type.

  The motor rotary shaft 25 has an end on one side in the axial direction (left side in FIG. 1) by the rolling bearing 40 and an end on the other side in the axial direction (right side in FIG. Each is rotatably supported.

  The reduction gear portion B includes an input shaft 30 having an input gear 30a, an intermediate shaft 31 having an input side intermediate gear 31a and an output side intermediate gear 31b as an intermediate gear, and an output shaft 36 having a final output gear 35. The input shaft 30 integrally has an input gear 30a, and the input shaft 30 is coaxially connected to the motor rotation shaft 25 by a spline fitting (including a serration fitting, hereinafter the same). The intermediate shaft 31 is integrally formed with the input side intermediate gear 31 a and the output side intermediate gear 31 b. The final output gear 36a and the output shaft 36 are integrally formed.

  The input shaft 30, the intermediate shaft 31 and the output shaft 36 are arranged in parallel to one another. Both ends of the input shaft 30 are rotatably supported on the casing 22 by rolling bearings 42 and 43, the intermediate shaft 31 by rolling bearings 44 and 45, and the output shaft 36 by rolling bearings 48 and 49, respectively. .

  More specifically, the end on the inboard side of the input shaft 30 is rotatably supported via the rolling bearing 42 in the gear shaft attachment hole 71a machined in the inner wall surface of the casing 22, and the outboard side An end portion is rotatably supported via a rolling bearing 43 in a gear shaft attachment hole 71 b formed in the inner wall surface of the casing 22.

  The intermediate shaft 31 has its inboard end rotatably supported via a rolling bearing 44 in a gear shaft attachment hole 72a machined in the inner wall surface of the casing 22, and the outboard end is It is rotatably supported via a rolling bearing 45 in a gear shaft mounting hole 72b machined in the inner wall surface of the casing 22.

  The output shaft 36 is rotatably supported at its inboard end in a gear shaft mounting hole 73a formed in the inner wall surface of the casing 22 via a rolling bearing 48, and the outboard end is It is rotatably supported via a rolling bearing 49 in a gear shaft mounting hole 73b machined in the inner wall surface of the casing 22.

  As shown in FIGS. 1 and 2, in the reduction gear portion B, the input gear 30a and the input intermediate gear 31a mesh with each other, and the output intermediate gear 31b and the final output gear 36a mesh with each other. The number of teeth of the input-side intermediate gear 31a is larger than the number of teeth of the input gear 30a and the output-side intermediate gear 31b, and the number of teeth of the final output gear 36a is larger than the number of teeth of the output-side intermediate gear 31b. From the above configuration, a parallel shaft gear reducer 39 that reduces rotational movement of the motor rotation shaft 25 in two steps is configured. The reduction gear mechanism composed of two-stage parallel shaft gears has a relatively small number of parts, and can achieve both a high reduction ratio and a reduction in size.

  In this embodiment, helical gears are used as the input gear 30a, the input-side intermediate gear 31a, the output-side intermediate gear 31b, and the final output gear 36a that constitute the reduction gear unit B. The helical gear is effective in that the noise is quiet and the torque fluctuation is small because the number of meshing teeth simultaneously increases and the tooth contact is dispersed. The module of each gear is preferably set to about 1 to 3 in consideration of the gear ratio of the gear and the number of revolutions of the limit.

  As shown in FIG. 1, the wheel bearing portion C is configured of an inner ring rotation type wheel bearing 50. The wheel bearing 50 is a double-row angular contact ball bearing mainly composed of an inner member 61 including a hub wheel 60 and an inner ring 52, an outer ring 53, balls 56 and a cage (not shown).

  A wheel mounting flange 60a is formed on the outer periphery of the hub wheel 60 on the outboard side, and the inner ring 52 is fitted and caulked and fixed to the small diameter step portion on the inboard side. After the wheel bearing 50 is assembled, the crimped portion 60 b fixes the inner ring 52 and applies a preload to the wheel bearing 50. An inner raceway surface 54a on the outboard side is formed on the outer periphery of the hub wheel 60, and an inner raceway surface 54b on the inboard side is formed on the outer periphery of the inner ring 52. Although not shown, a brake disc and a wheel are attached to the wheel attachment flange 60a. On the inner periphery of the outer ring 53, double rows of outer race surfaces 55 are formed corresponding to the inner race surface 54a of the hub wheel 60 and the inner race surface 54b of the inner ring 52. The output shaft 36 is splined to the hub wheel 60 and is coupled so as to be able to transmit torque.

  A flange portion 53 a is formed on the outer periphery of the outer ring 53, and the flange portion 53 a is fastened and fixed to the casing 22 by a bolt 71. Thus, the wheel bearing 50 and the casing 22 are coupled.

  In the in-wheel motor drive device 21, in order to cool the electric motor 26 and lubricate and cool the reduction gear 39, lubricating oil is supplied to each part by a rotary pump (not shown). The inside of the bearing for the wheel bearing 50 is lubricated by grease. Further, cooling fins 22 a for air cooling are provided on the outer peripheral surface of the casing 22.

  The in-wheel motor drive device 21 is housed inside the wheel housing 15 (see FIG. 10) and serves as an unsprung load, so reduction in size and weight is essential. By combining the parallel shaft gear reducer 39 configured as described above with the electric motor 26, it becomes possible to use a small electric motor 26 of low torque and high rotation type. For example, in the case of using the parallel shaft gear reducer 39 having the reduction ratio 11, the electric motor 26 can be miniaturized by using the electric motor 26 rotating at a high speed of about ten thousand and several thousand revolutions per minute. As a result, a compact in-wheel motor drive device 21 can be realized, and the unsprung weight can be suppressed to obtain the electric vehicle 11 excellent in traveling stability and NVH characteristics.

  The whole structure of the in-wheel motor drive device 21 of this embodiment is as described above. Next, the characteristic configuration is described.

  As described above, both ends of the gear shaft constituting the reduction gear portion B are respectively formed on the gear shaft mounting holes 71a, 71b, 72a, 72b, 73a, 73b machined in the inner wall surface of the casing 22; It is rotatably inserted and fixed via 43, 44, 45, 48, 49.

  The tolerance of the hole diameter of the gear shaft attachment holes 71a, 71b, 72a, 72b, 73a, 73b to be machined in the inner wall surface of the casing 22, that is, the inner diameter is IT6 to 7 (about 30 μm). If machining is performed using a boring head or the like which can be finely adjusted, dimensional tolerances can be satisfied if the rotational accuracy of the machine tool is maintained.

  However, the positioning accuracy of the gear shaft mounting holes 71a, 71b, 72a, 72b, 73a, 73b disposed on the inner wall surface of the casing 22 of the reduction gear unit B is the positioning accuracy when the machine tool moves, the workpiece In this case, it is necessary to consider many error factors such as deformation of the casing 22 at the time of chucking, thermal expansion of the workpiece and machine tool due to environmental temperature change, so the tolerance of about φ0.1 mm I can not but tolerate.

The axial center position of the inner diameter of the gear shaft mounting holes 71a, 71b, 72a, 72b, 73a, 73b is normal on the inner wall surface of the casing 22 of the reduction gear portion B due to this processing error (position of O ₁ in FIG. ₂ ) through the roller bearings 42, 43, 44, 45, 48, 49 to the gear shaft mounting holes 71a, 71b, 72a, 72b, 73a, 73b. The axial center of the gear shaft to be inserted and fixed is decentered from the correct axial position (the position of O ₁ in FIG. 2), which affects the life of the gear of the reduction gear portion B and the sound and vibration. Become.

In the present invention, even if the inner diameters of the gear shaft mounting holes 71a, 71b, 72a, 72b, 73a, 73b are eccentric due to processing errors (for example, the position of O ₂ in FIG. 2), the eccentricity is corrected , The shaft center of the gear shaft inserted and fixed to the gear shaft mounting holes 71a, 71b, 72a, 72b, 73a, 73b via the rolling bearings 42, 43, 44, 45, 48, 49 (for example, FIG. (O ₁ position) to be able to be placed.
For example, as shown in FIG. 3, the end portion of the outboard side of the output shaft 36, the axis O ₂ of the inner diameter of the gear shaft mounting hole 73b to be inserted and fixed is upwardly from the axis O ₁ of the normal by the processing error When the eccentricity (eccentricity amount a) is made, the eccentricity amount a is corrected, and the axial center of the end portion on the outboard side of the output shaft 36 inserted into the inner diameter of the inner ring of the rolling bearing 42, An embodiment which can be made to coincide with the normal axis O ₁ will be described below.

  As shown in FIG. 3, the inner diameter of the gear shaft mounting hole 73b is set larger than the outer diameter of the rolling bearing 42 to which the end on the outboard side of the output shaft 36 is inserted and fixed, and the inner diameter of the gear shaft mounting hole 73b. The inner eccentric ring 81 and the outer eccentric ring 82 can be rotatably inserted and fixed between the inner and outer eccentric rings 81 and 82 without clearance.

  The inner eccentric ring 81 and the outer eccentric ring 82 equalize the relative values of eccentricity to their respective outer diameters at several μm level, and the inner eccentric ring 81 has no gap with respect to the inner diameter of the outer eccentric ring 82 It is rotatable within a 360 ° range.

  Further, the inner diameter of the inner eccentric ring 81 is dimensioned so as to be inserted and fixed without any gap with respect to the outer diameter of the rolling bearing 49, and the inner diameter of the gear shaft attachment hole 73b processed in the casing 22 is an outer eccentricity. The outer diameter of the ring 82 is dimensioned so as to be inserted and fixed without gaps. The internal diameter of the gear shaft attachment hole 73b processed in the casing 22 can be processed with high accuracy by using a boring head or the like.

  Regarding the positional accuracy of the gear shaft attachment hole 73b in the casing 22 where high precision processing is difficult, an error in which the radius of twice the eccentricity of the inner diameter with respect to the outer diameter of each of the inner eccentric ring 81 and the outer eccentric ring 82 is a radius Manage within. In this embodiment, the amount of eccentricity of the inner diameter with respect to the outer diameter of each of the inner eccentric ring 81 and the outer eccentric ring 82 is set to about 0.1 mm.

  Next, a method of correcting the eccentricity of the shaft center of the gear shaft attachment hole 73b using the inner eccentric ring 81 and the outer eccentric ring 82 will be described.

  First, as shown in FIG. 4, the rolling bearing 49 is inserted into the inner eccentric ring 81 combined with the outer eccentric ring 82 in an arbitrary phase, and further inserted into the gear shaft attachment hole 73b in an arbitrary phase.

How much the axis of the rolling bearing 49 inserted into the gear shaft mounting hole 73b deviates from the normal axis O ₁ , that is, the amount and direction of deviation in the radial direction Measure using etc.

Then, if the amount of displacement in the radial direction is corrected by the phase difference between the outer eccentric ring 82 and the inner eccentric ring 81 and the direction of the displacement is fixed by the fixed phase of the outer eccentric ring 82 to the gear shaft mounting hole 73b, as shown in 4, the axis of the rolling bearing 49 is corrected to the position of the axis O ₁ of the normal.

  After this, the outer eccentric ring 82 adheres and fixes the inner eccentric ring 81 to the inner diameter of the outer eccentric ring 82 with respect to the inner diameter of the gear shaft mounting hole 73b to prevent rotation even by bearing torque. When the outboard end of the output shaft 36 is inserted into and fixed to the inner diameter of the inner ring of the rolling bearing 49, the assembly is completed as shown in FIG.

  Next, when correcting the phases of the outer eccentric ring 82 and the inner eccentric ring 81, as shown in FIGS. 5-8, the cylindrical portion 91 having the same diameter as the outer diameter of the rolling bearing 49 is provided. It is possible to use a positioning jig 90 in which 91 is disposed at the correct position of the rolling bearing 49 with respect to the casing 22 of the reduction gear portion B.

In the positioning jig 90, as shown in FIG. 5, a mounting arm 92 is provided on a cylindrical portion 91 having the same diameter as the outer diameter of the rolling bearing 49, and the positioning pin 93 of the mounting arm 92 is used as a casing of the reduction gear portion B. The axial center of the cylindrical portion 91 is arranged to coincide with the exact center O ₁ of the rolling bearing 49 with respect to the casing 22 of the reduction gear portion B by fitting in the positioning hole 94 provided in 22.

  The two positioning holes 94 into which the positioning pins 93 of the mounting arm 92 are fitted can use bolt holes for mounting the casing 22 of the reduction gear portion B.

Eccentricity correction using this positioning jig 90 is performed as follows.
First, as shown in FIG. 7, the inner eccentric ring 81 and the outer eccentric ring 82 are inserted in advance into the outer diameter of the cylindrical portion 91 of the positioning jig 90 at an arbitrary phase. Next, as shown in FIG. 8, adjust the phases of the inner eccentric ring 81 and the outer eccentric ring 82 in the two positioning holes 94 of the casing 22 of the reduction gear portion B, as shown in FIG. When fitted into while, it is arranged so the axis of the cylindrical portion 91 of the positioning jig 90 is coincident with the exact center O ₁ of the casing 22 of the reducer unit B.

After that, when the positioning jig 90 is removed and the rolling bearing 49 is inserted into the inner diameter of the inner eccentric ring 81, the axis of the rolling bearing 49 and the accuracy of the casing 22 of the reduction gear portion B as shown in FIG. It can be arranged to coincide with the central O ₁ .

In the above embodiment, the eccentricity correction mechanism of the present invention is applied to only one axis, but can be applied to a multi-axis gear shaft.
By employing a damping material such as rubber, resin, damping alloy or the like as the material of the inner eccentric ring 81 and the outer eccentric ring 82, sound and vibration to the outside of the reduction gear portion B can be isolated. .

  Further, although the above embodiment uses two eccentric rings of the inner eccentric ring 81 and the outer eccentric ring 82, the outer ring outer diameters of the rolling bearings 42, 43, 44, 45, 48, 49 are eccentric. By doing this, the inner eccentric ring 81 can be omitted.

  Also, the outer eccentric ring 82 increases the coefficient of friction by applying anti-slip coating, blast, etc. to the inner and outer diameters thereof, and the outer diameter of the inner eccentric ring 81 and the gear shaft attachment holes 71a, 71b, 72a, By providing a press fit for the inner diameter of 72b, 73a, 73b, the step of bonding and fixing can be omitted.

  Although the reduction gear part B of the in-wheel motor drive device 21 of each above embodiment illustrated the thing using the parallel-shaft-type gear reduction gear 39 of two-step deceleration, it is not limited to this, 1 step You may make it more than deceleration or three-step deceleration.

  The present invention is not limited to the embodiment described above, and it goes without saying that the present invention can be practiced in various forms without departing from the scope of the present invention, and the scope of the present invention is not limited to the patent The scope of the present invention is defined by the claims, and further includes the meaning of equivalents described in the claims, and all changes within the scope.

21: In-wheel motor drive device 22: Casing 30: Input shaft 31: Intermediate shaft 36: Output shaft 40, 41, 42, 43, 44, 45, 48, 49: Rolling bearings 71a, 71b, 72a, 72b, 73a, 73b: gear shaft mounting hole 81: inner eccentric ring 82: outer eccentric ring 90: positioning jig 91: cylindrical portion 92: mounting arm 93: positioning pin 94: positioning hole A: electric motor portion B: reduction gear portion C: Wheel bearing

Claims (4)

The electric motor unit generates a driving force, a reduction gear unit that decelerates and outputs the rotation of the electric motor unit, and a wheel bearing unit transmits an output from the reduction gear unit to the wheels, and the reduction gear unit is An in-wheel comprising a plurality of gear shafts housed in a casing, wherein both ends of each gear shaft are rotatably supported via rolling bearings in a gear shaft mounting hole formed on the opposing inner wall surface of the casing In the motor drive,
Between the outer diameter of the rolling bearing and the inner diameter of the gear shaft mounting hole, the inner diameter is eccentric to the outer diameter, and the outer diameter is rotatable relative to the inner diameter of the gear shaft mounting hole A ring, and an inner eccentric ring having an outer diameter the same size as the inner diameter of the outer eccentric ring, eccentric to the outer diameter, and rotatable with respect to the inner diameter of the outer eccentric ring; In the circle which arrange | positions and makes the said outer eccentric ring and the inner eccentric ring mutually rotate relatively, and makes twice the amount of eccentricity of the internal diameter with respect to each outer diameter of an outer eccentric ring and an inner eccentric ring a radius An in-wheel motor drive device characterized in that the axis of the gear shaft, which is inserted into and fixed to the inner diameter of the inner eccentric ring, is movable at any point of the above.   The in-wheel motor drive according to claim 1, wherein the material of at least one of the outer eccentric ring and the inner eccentric ring is made of metal, rubber or resin of high damping.   The outer diameter of the outer eccentric ring is press-fit to the inner diameter of the gear shaft mounting hole, the outer diameter of the inner eccentric ring is press-fitted to the inner diameter of the outer eccentric ring, and the inner diameter of the inner eccentric ring is The in-wheel motor drive device according to claim 1, wherein the in-wheel motor drive device according to claim 1 is press-fit to the outer diameter of the outer ring of the rolling bearing.   The in-wheel motor drive according to claim 1, wherein the inner eccentric ring is integrated with an outer ring of the rolling bearing.

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