JP2010060018A - Oscillating gear device, transmission ratio variable mechanism, and vehicular steering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oscillating gear device having high transmission efficiency and restricted in vibration and noise, and to provide a transmission ratio variable mechanism and a vehicular steering device. <P>SOLUTION: The transmission ratio variable mechanism 5 includes: an input member 20 and an output member 22 respectively having the center axis thereof on a first axis A and capable of rotating around the first axis A: and an inner ring 391 connecting the input member 20 and the output member 22 to each other so as to allow differential rotation of the input member 20 and the output member 22. The inner ring 391 has the center axis thereof on a second axis B inclined relative to the first axis A and can be rotated around the second axis B. The center of gravity G1 of the inner ring 391 is arranged on the first axis A. The input member 20 and the inner ring 391 are connected to each other through a first magnetic engagement mechanism 64 to transmit the torque without a contact. The inner ring 391 and the output member 22 are connected to each other through a second magnetic engagement mechanism 67 to transmit the torque without contact. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an oscillating gear device, a transmission ratio variable mechanism, and a vehicle steering device.

  As an oscillating gear device including a gear that performs oscillating motion, there is an oscillating gear device in which an input shaft and an output shaft are connected by first to fourth gears (see, for example, Patent Document 1). The first gear is fixed to the housing. The second gear and the third gear are provided on a rotating body supported by the inclined portion of the input shaft. The fourth gear is connected to the output shaft. The first gear and the second gear mesh with each other, and the third gear and the fourth gear mesh with each other. The axis of the inclined portion is inclined with respect to the axis of the first gear. With the above configuration, a swinging motion is generated in the rotating body as the input shaft rotates. This oscillating motion is a surface shake motion around the intersection of the axis of the inclined portion and the axis of the input shaft.

  The meshing of the first gear and the second gear is the meshing of the roller provided in the first gear and the concave groove provided in the second gear, both of which occur when the first and second gears mesh. Is absorbed by the rolling of the rollers. More specifically, the roller is fitted in a recess formed in the first gear. Both ends of the roller are rotatably held by a retainer attached to the first gear. A semi-cylindrical convex tooth is formed by a roller protruding from the concave portion. Further, the second gear is formed with a groove having a semicircular cross section. When the rotating body performs a swinging motion, the roller of the first gear meshes with the concave groove of the second gear. At this time, the roller rolls with respect to the groove so that sliding between the roller and the groove is difficult to occur.

However, during the oscillating motion of the rotating body, a large frictional force acts on the roller in the axial direction between the roller and the groove, and the roller is strongly rubbed against the groove, so that the roller rolls smoothly. Will be hindered, leading to deterioration of transmission efficiency.
JP 2008-133861 A

In this type of gear device, as shown in FIG. 5 of Patent Document 1, the center of gravity of the rotating body (oscillating body) is not disposed on the axis of the input / output shaft. Therefore, vibration and noise resulting from the swinging rotation of the rotating body are generated.
The present invention has been made under such a background, and an object of the present invention is to provide a rocking gear device, a transmission ratio variable mechanism, and a vehicle steering device that have high transmission efficiency and low vibration and noise.

  In order to achieve the above object, the present invention provides an input member (20) and an output member (22) each having a central axis on the first axis (A) and rotatable about the first axis, An intermediate member (391) for connecting the input member and the output member so as to allow differential rotation of the input member and the output member, wherein the intermediate member is inclined with respect to the first axis. A central axis on the second axis (B) and rotatable about the second axis; the center of gravity (G1) of the intermediate member is disposed on the first axis; The input member and the intermediate member are connected to each other through a first magnetic engagement mechanism (64) so as to transmit torque without contact, and the intermediate member and the output member are connected to a second magnetic engagement mechanism (67). Torque can be transmitted without contact via A oscillating gear device (6), characterized in that it is sintered (claim 1).

  According to the present invention, the center of gravity of the intermediate member is disposed on the first axis. Thereby, when the intermediate member rotates around the second axis, the center of gravity of the intermediate member does not swing around the first axis, and as a result, rotational vibration of the intermediate member can be significantly reduced. A pair of gears are formed on the opposing end surfaces of the input member and the intermediate member and mechanically engaged with each other, and a pair of gears are formed on the opposing end surfaces of the intermediate member and the output member. When meshing with each other, it is not possible to dispose the center of gravity of the intermediate member on the first axis as in the present invention, because the corresponding gears do not mesh well. The configuration of the present invention in which the center of gravity of the intermediate member is arranged on the first axis makes it possible to transmit torque between the input member and the intermediate member in a non-contact manner by the first magnetic engagement mechanism, and the second magnetic This is possible because the intermediate member and the output member can transmit torque in a non-contact manner by the meshing mechanism. The intermediate member is torque-transmitted in a non-contact manner with the corresponding input member and output member. Thereby, there is no mechanical contact both between the input member and the intermediate member and between the intermediate member and the output member. Therefore, since sliding resistance can be eliminated, transmission efficiency can be made extremely high, and driving noise of the apparatus can be made extremely small.

  Further, in the present invention, the first magnetic engagement mechanism is configured such that each of the opposing portions (201a, 391a) of the input member and the intermediate member has an annular shape centering on the respective central axes of the input member and the intermediate member. The second magnetic engagement mechanism includes a plurality of magnetic poles (71, 72, 73, 74) that are magnetically engageable with each other, and the second magnetic engagement mechanism is configured so that the intermediate member and the output member face each other (391b, Each of 221a) may include a plurality of magnetic poles (77, 78, 79, 80) that are arranged in an annular shape around the central axis of each of the intermediate member and the output member and are magnetically engageable with each other. (Claim 2).

In this case, the first magnetic engagement mechanism can be realized with a simple configuration in which a plurality of magnetic poles are provided on each of the input member and the intermediate member. Further, the second magnetic engagement mechanism can be realized by a simple configuration in which a plurality of magnetic poles are provided on each of the intermediate member and the output member.
Further, in the present invention, the above-described oscillating gear device and the electric motor (23) for driving the intermediate member are provided, and the rotation angle (θ2) of the output member with respect to the rotation angle (θ1) of the input member. The ratio (θ2 / θ1) may be changeable (claim 3). In this case, when the electric motor drives the intermediate member, the ratio of the rotation angle of the output member to the rotation angle of the input member can be changed.

  The present invention also provides a transmission ratio which is a ratio of the turning angle (θ2) of the steered wheels (4L, 4R) to the steering angle (θ1) of the steering member (2) using the transmission ratio variable mechanism (5). A vehicle steering apparatus (1) capable of changing (θ2 / θ1), wherein the input member is connected to a steering member, and the output member is connected to a steered wheel side member (12). A vehicle steering apparatus is provided.

  In this case, by making the transmission ratio variable, the turning angle of the steered wheels with respect to the steering of the steering member can be optimized according to the traveling state of the vehicle. For example, when the vehicle is stopped or running at low speed, such as when entering a garage, by increasing the transmission ratio, the turning amount of the steered wheels can be increased relative to the steering amount. The amount can be reduced. Further, when the vehicle is traveling on a snowy road or the like, so-called active steering can be performed in which the counter steer operation is automatically performed by the transmission ratio variable mechanism.

  In the above description, numbers in parentheses represent reference numerals of corresponding components in the embodiments described later, but the scope of the claims is not limited by these reference numerals.

Preferred embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic diagram showing a schematic configuration of a vehicle steering apparatus 1 including a transmission ratio variable mechanism including a swing gear apparatus according to an embodiment of the present invention. Referring to FIG. 1, a vehicle steering apparatus 1 applies a steering torque applied to a steering member 2 such as a steering wheel to left and right steered wheels 4L and 4R via a steering shaft 3 as a steering shaft. The steering is given. This vehicle steering apparatus 1 has a VGR (Variable Gear Ratio) function capable of changing a transmission ratio θ2 / θ1 as a ratio of a steered wheel turning angle θ2 to a steering angle θ1 of a steering member 2. .

  The vehicle steering apparatus 1 includes a steering member 2 and a steering shaft 3 connected to the steering member 2. The steering shaft 3 includes first to third shafts 11 to 13 as first to third shafts arranged coaxially with each other. The first axis A as the central axis of the first to third shafts 11 to 13 is also the rotational axis of the first to third shafts 11 to 13. Hereinafter, the axial direction S of the steering shaft 3 is simply referred to as the axial direction S, the circumferential direction C of the steering shaft 3 is simply referred to as the circumferential direction C, and the radial direction R of the steering shaft 3 is simply referred to as the radial direction R.

  A steering member 2 is connected to one end of the first shaft 11 so as to be able to rotate together. The other end 11 b of the first shaft 11 and the one end 12 a of the second shaft 12 are connected via the transmission ratio variable mechanism 5 so as to be differentially rotatable. The other end of the second shaft 12 and one end of the third shaft 13 are connected via a torsion bar 14 so as to be elastically rotatable relative to each other and capable of transmitting power within a predetermined range.

The other end of the third shaft 13 is connected to the steered wheels 4L and 4R via the universal joint 7, the intermediate shaft 8, the universal joint 9, the steering mechanism 10, and the like.
The steered mechanism 10 includes a pinion shaft 15 connected to the universal joint 9, and a rack shaft 16 as a steered shaft that has a rack 16a that meshes with the pinion 15a at the tip of the pinion shaft 15 and extends in the left-right direction of the vehicle. Yes. Knuckle arms 18L and 18R are connected to the pair of ends of the rack shaft 16 via tie rods 17L and 17R, respectively.

  With the above configuration, the rotation of the steering member 2 is transmitted to the steering mechanism 10 via the steering shaft 3 and the like. In the turning mechanism 10, the rotation of the pinion 15 a is converted into the axial movement of the rack shaft 16. The axial movement of the rack shaft 16 is transmitted to the corresponding knuckle arms 18L and 18R via the tie rods 17L and 17R, and the knuckle arms 18L and 18R rotate. Accordingly, the corresponding steered wheels 4L and 4R connected to the knuckle arms 18L and 18R are respectively steered.

  The transmission ratio variable mechanism 5 is for changing the rotation transmission ratio (transmission ratio θ2 / θ1) between the first and second shafts 11 and 12 of the steering shaft 3, and is a nutation gear mechanism. . The transmission ratio variable mechanism 5 includes an input member 20 provided at the other end 11b of the first shaft 11, an output member 22 provided at one end 12a of the second shaft 12 as a steered wheel side member, and an input. A bearing ring unit 39 interposed between the member 20 and the output member 22 and a transmission ratio variable mechanism motor 23 are included.

The oscillating gear device 6 is formed by the input member 20, the output member 22, and an inner ring 391 described later of the raceway ring unit 39. The transmission ratio variable mechanism 5 can change the ratio of the turning angle θ2 as the rotation angle of the output member 22 to the turning angle θ1 as the rotation angle of the input member 20.
The input member 20 is connected to the steering member 2 and the first shaft 11 so as to be coaxial and rotatable. The output member 22 is connected to the second shaft 12 so as to be coaxial and rotatable. The first axis A is the central axis of the input member 20 and the output member 22, and is the rotation axis.

The bearing ring unit 39 is a bearing member including an inner ring 391 as a first bearing ring, an outer ring 392 as a second bearing ring, and rolling elements 393 such as balls interposed between the inner ring 391 and the outer ring 392. .
The inner ring 391 connects the input member 20 and the output member 22 so as to be differentially rotatable, and constitutes an intermediate member. The inner ring 391 and the outer ring 392 have a central axis B that is inclined with respect to the first axis A. The center axis B is the center axis and the rotation axis of the inner ring 391. Further, the inner ring 391 and the outer ring 392 can rotate around the first axis A (so-called Coriolis movement) as the transmission ratio variable mechanism motor 23 as an actuator is driven.

The transmission ratio variable mechanism motor 23 is arranged radially outward of the track ring unit 39, and changes the transmission ratio θ2 / θ1 by changing the number of rotations of the outer ring 392 around the first axis A. .
The transmission ratio variable mechanism motor 23 is, for example, an electric brushless motor, and includes a rotor 231 that can rotate around the first axis A with the outer ring 392 of the raceway ring unit 39, and surrounds the rotor 231 in a housing 24. And a fixed stator 232.

  The vehicle steering apparatus 1 includes a steering assist force applying mechanism 19 for applying a steering assist force to the steering shaft 3. The steering assist force applying mechanism 19 includes the second shaft 12 as an input shaft continuous with the output member 22 of the transmission ratio variable mechanism 5, the third shaft 13 as an output shaft continuous with the steering mechanism 10, A torsion bar 14 that connects the second and third shafts 12 and 13, a torque sensor 44 that detects torque transmitted between the second shaft 12 and the third shaft 13, and a steering assisting device. A steering assist motor 25 as an actuator, and a speed reduction mechanism 26 interposed between the steering assist motor 25 and the third shaft 13 are included.

The steering assist motor 25 is an electric motor such as a brushless motor. The output of the steering assist motor 25 is transmitted to the third shaft 13 via the speed reduction mechanism 26.
The speed reduction mechanism 26 is composed of, for example, a worm gear mechanism, and is connected to a worm shaft 27 as a drive gear connected to the output shaft 25 a of the steering assist motor 25, meshed with the worm shaft 27 and connected to the third shaft 13 so as to be able to rotate together. And a worm gear 28 as a driven gear.

  The transmission ratio variable mechanism 5 and the steering assist force applying mechanism 19 are provided in the housing 24. The housing 24 is disposed in a passenger compartment (cabin) of the vehicle and surrounds the first and second shafts 11 and 12. The housing 24 may be disposed so as to surround the intermediate shaft 8, may be disposed so as to surround the pinion shaft 15, or may be disposed in the engine room of the vehicle.

The driving of the transmission ratio variable mechanism motor 23 and the steering assist motor 25 is controlled by a control unit 29 including a CPU, a RAM, and a ROM, respectively. The control unit 29 is connected to the transmission ratio variable mechanism motor 23 via the drive circuit 40, and is connected to the steering assist motor 25 via the drive circuit 41.
The control unit 29 includes a steering angle sensor 42, a motor resolver 43 as a rotation angle detection means for detecting the rotation angle of the transmission ratio variable mechanism motor 23, a torque sensor 44 as a torque detection means, and a turning angle sensor 45. A vehicle speed sensor 46 and a yaw rate sensor 47 are connected to each other.

A signal about the rotation angle of the first shaft 11 is input from the steering angle sensor 42 to the control unit 29 as a value corresponding to the steering angle θ1 that is an operation amount from the straight traveling position of the steering member 2.
A signal regarding the rotation angle θr of the rotor 231 of the transmission ratio variable mechanism motor 23 is input from the motor resolver 43 to the control unit 29.
A signal regarding the torque T acting between the second and third shafts 12 and 13 is input from the torque sensor 44 to the control unit 29.

A signal about the rotation angle of the third shaft 13 (output member 22) is input from the turning angle sensor 45 to the control unit 29 as a value corresponding to the turning angle θ2.
A signal regarding the vehicle speed V is input from the vehicle speed sensor 46 to the control unit 29.
A signal regarding the yaw rate γ of the vehicle is input from the yaw rate sensor 47 to the control unit 29.

The control unit 29 controls the driving of the transmission ratio variable mechanism motor 23 and the steering assist motor 25 based on the signals of the sensors 42 to 47.
With the above configuration, the output of the transmission ratio variable mechanism 5 is transmitted to the steering mechanism 10 via the steering assist force applying mechanism 19. More specifically, the steering torque input to the steering member 2 is input to the input member 20 of the transmission ratio variable mechanism 5 via the first shaft 11, and the steering assist force applying mechanism 19 of the steering assist force applying mechanism 19 is changed from the output member 22. Is transmitted to the second shaft 12.

The steering torque transmitted to the second shaft 12 is transmitted to the torsion bar 14 and the third shaft 13, and together with the output from the steering assist motor 25, is transmitted to the steering mechanism 10 via the intermediate shaft 8 or the like. The
FIG. 2 is a cross-sectional view showing a more specific configuration of the main part of FIG. Referring to FIG. 2, the housing 24 is formed by, for example, forming a metal such as an aluminum alloy into a cylindrical shape, and includes first to third housings 51 to 53. In the housing 24, first to eighth bearings 31 to 38 are accommodated. Each of the first to fifth bearings 31 to 35 and the seventh to eighth bearings 37 to 38 is a rolling bearing such as an angular ball bearing, and the sixth bearing 36 is a rolling bearing such as a needle roller bearing. It is.

  The first housing 51 has a cylindrical shape and houses the transmission ratio variable mechanism 5 and the transmission ratio variable mechanism motor 23. One end of the first housing 51 is covered with an end wall member 54. One end of the first housing 51 and the end wall member 54 are fixed to each other using a fastening member 55 such as a bolt. An annular convex portion 57 at one end of the second housing 52 is fitted to the inner peripheral surface 56 at the other end of the first housing 51. The first and second housings 51 and 52 are fixed to each other using a fastening member (not shown) such as a bolt.

The second housing 52 has a cylindrical shape and accommodates the torque sensor 44 and the motor resolver 43. The inner peripheral surface 60 at one end of the third housing 53 is fitted to the outer peripheral surface 59 at the other end of the second housing 52.
The third housing 53 has a cylindrical shape and houses the speed reduction mechanism 26. An annular end wall 61 is provided at the other end of the third housing 53.

FIG. 3 is an enlarged view of the transmission ratio variable mechanism 5 of FIG. 2 and its surroundings. Referring to FIG. 3, input member 20 and output member 22 of transmission ratio variable mechanism 5 each have an annular shape.
The input member 20 includes an input member main body 201 and a cylindrical portion 202 fixed to the inner diameter portion of the input member main body 201.
The first shaft 11 is connected to the cylindrical portion 202 so as to be able to rotate together by being inserted through the insertion hole 202 a of the cylindrical portion 202. The first shaft 11 is rotatably supported by the first housing 51 via the cylindrical portion 202 of the input member 20 and the first bearing 31.

The output member 22 includes an output member main body 221 and a cylindrical portion 222 extending from the inner diameter portion of the output member main body 221.
The second shaft 12 is connected to the output member 22 so as to rotate together with the output member 22 by being inserted through the insertion hole 222 a of the cylindrical portion 222 of the output member 22. The second shaft 12 is rotatably supported at the tip of an annular extending portion 92 described later of the second housing 52 via the cylindrical portion 22 of the output member 22 and the third bearing 33.

The cylindrical portion 202 of the input member 20 supports the one end 12a of the second shaft 12 via the eighth bearing 38 so as to be rotatable.
The outer ring 392 of the bearing ring unit 39 is held in an inclined hole 63 formed in the inner periphery of the rotor 231 of the transmission ratio variable mechanism motor 23, and rotates around the first axis A together with the rotor 231. . As the rotor 231 rotates around the first axis A, the race ring unit 39 performs Coriolis motion.

The outer ring 392 may connect the input member 20 and the output member 22 so as to be differentially rotatable, and the inner ring 391 may be connected to the rotor 231 of the transmission ratio variable mechanism motor 23 so as to be rotatable together. In this case, the race ring unit 39 is an inner ring support type.
FIG. 4 is a partial cross-sectional side view of the main part of the transmission ratio variable mechanism 5. With reference to FIGS. 3 and 4, a first magnetic engagement mechanism 64 is provided in each of the input member main body 201 and the inner ring 391. As a result, the input member 20 and the inner ring 391 can transmit torque without contact. A second magnetic engagement mechanism 67 is provided on each of the inner ring 391 and the output member 22. As a result, the inner ring 391 and the output member 22 can transmit torque without contact.

The first magnetic engagement mechanism 64 is a first magnet 65 provided at the opposed end 201a facing the inner ring 391 of the input member main body 201, and one end of the inner ring 391 facing the input member main body 201. And a second magnet 66 provided at the opposite end 391a.
The first magnet 65 is a permanent magnet made of an integrally formed product having an annular shape with the first axis A as the center, and includes a plurality of magnetic poles 71 and 72 arranged along the circumferential direction C. In the first magnet 65, N poles 71 and S poles 72 are alternately arranged at an equal pitch over the entire area in the circumferential direction C. In the present embodiment, for example, 49 pairs of N pole 71 and S pole 72 are provided. The central axis of the first magnet 65 is the first axis A. The first magnet 65 and the input member main body 201 can be rotated together around the first axis A.

  The second magnet 66 is a permanent magnet made of an integrally formed product having an annular shape centering on the second axis B, and is along the circumferential direction D (hereinafter simply referred to as the circumferential direction D) of the second axis B. A plurality of magnetic poles 73 and 74 arranged side by side are included. In the second magnet 66, N poles 73 and S poles 74 are alternately arranged at an equal pitch over the entire area in the circumferential direction D. In the present embodiment, for example, 50 pairs of N pole 73 and S pole 74 are provided. The central axis of the second magnet 66 is the second axis B. The second magnet 66 and the inner ring 391 can be rotated around the second axis B.

  FIG. 5 is a side view of the main part viewed along the direction of arrow V in FIG. With reference to FIGS. 4 and 5, the second magnet 66 is opposed to the first magnet 65 in the axial direction S. Since the first magnet 65 is inclined with respect to the second magnet 66, some of the magnetic poles 71 and 72 of the first magnet 65 and some of the magnetic poles 73 and 74 of the second magnet 66 are Are close to each other. The portions of the first magnet 65 and the second magnet 66 that are close to each other form a meshing region 75 that meshes magnetically. In the meshing region 75, one magnetic pole (N pole 71 or S pole 72) of the first magnet 65 and the other magnetic pole (S pole 74 or N pole 73) of the second magnet 66 are attracted to each other. The first and second magnets 65 and 66 are magnetically coupled. In the present embodiment, the number of poles of the first magnet 65 is relatively small and the number of poles of the second magnet 66 is relatively large, but the second axis B as the axis of the bearing ring unit 39 is the first axis B. The pitch P1 (arrangement pitch) of the magnetic poles 71 and 72 of the first magnet 65 and the pitch P2 of the second magnet 66 are equal to or close to each other because they are inclined with respect to the first axis A. It has become.

As described above, the number of the magnetic poles 71 and 72 of the first magnet 65 is different from the number of the magnetic poles 73 and 74 of the second magnet 66. The speed ratio between the input member main body 201 and the inner ring 391 is determined by the difference between the number of magnetic poles 71 and 72 of the first magnet 65 and the number of magnetic poles 73 and 74 of the second magnet 66.
Each of the first and second magnets 65 and 66 may be formed by arranging a plurality of arc-shaped segment magnets to form a ring as a whole.

Referring to FIGS. 3 and 4 again, the second magnetic engagement mechanism 67 includes a third magnet 68 provided at the opposite end 391b as the other end of the inner ring 391 that faces the output member main body 221. And a fourth magnet 69 provided at the opposed end 221a facing the inner ring 391 of the output member main body 221.
The third magnet 68 is a permanent magnet made of an integrally formed product having an annular shape around the second axis B, and includes a plurality of magnetic poles 77 and 78 arranged along the circumferential direction D. In the third magnet 68, N poles 77 and S poles 78 are alternately arranged at equal pitches over the entire area in the circumferential direction D. In the present embodiment, for example, 50 pairs of N pole 77 and S pole 78 are provided. The central axis of the third magnet 68 is the second axis B. The third magnet 68 and the inner ring 391 can be rotated around the second axis B.

  The fourth magnet 69 is a permanent magnet made of an integrally formed product having an annular shape with the first axis A as the center, and includes a plurality of magnetic poles 79 and 80 arranged along the circumferential direction C. In the fourth magnet 69, N poles 79 and S poles 80 are alternately arranged at an equal pitch over the entire circumferential direction C. In the present embodiment, for example, 50 pairs of N pole 79 and S pole 80 are provided. The central axis of the fourth magnet 69 is the first axis A. The fourth magnet 69 and the output member main body 221 can be rotated around the first axis A.

  FIG. 6 is a side view of the main part viewed along the direction of arrow VI in FIG. With reference to FIGS. 4 and 6, the third magnet 68 is opposed to the fourth magnet 69 in the axial direction S. Since the third magnet 68 is inclined with respect to the fourth magnet 69, some of the magnetic poles 77 and 78 of the third magnet 68 and some of the magnetic poles 79 and 80 of the fourth magnet 69 Are close to each other. The portions of the third magnet 68 and the fourth magnet 69 that are close to each other form a meshing region 81 that meshes magnetically. In the meshing region 81, one magnetic pole (N pole 77 or S pole 78) of the third magnet 68 and the other magnetic pole (S pole 80 or N pole 79) of the fourth magnet 69 are attracted to each other. The third and fourth magnets 68 and 69 are magnetically coupled. In the present embodiment, the number of poles of the third magnet 68 and the number of poles of the fourth magnet 69 are equal, but the second axis B as the axis of the bearing ring unit 39 is inclined with respect to the first axis A. Therefore, the pitch P3 of the magnetic poles 77 and 78 of the third magnet 68 is longer than the pitch P4 of the fourth magnet 69.

Each of the third and fourth magnets 68 and 69 may be formed by arranging a plurality of arc-shaped segment magnets to form a ring as a whole. Further, the number of poles of the third magnet 68 and the number of poles of the fourth magnet 69 may be different.
Referring to FIG. 4, with respect to the radial direction of the second axis B, the distance E1 between the second axis B and the meshing region 75 of the first magnetic meshing mechanism 64 is relatively short, The distance E2 between the axis B and the meshing region 81 of the second magnetic meshing mechanism 67 is relatively long.

The center of gravity G0 of the bearing ring unit 39 is disposed on the first axis A and is disposed on the second axis B. That is, the center of gravity G0 of the track ring unit 39 is disposed on the intersection F of the first axis A and the second axis B.
Specifically, the density of the entire area including the second and third magnets 66 and 68 of the inner ring 391 of the bearing ring unit 39, that is, the mass per unit volume is made uniform. Similarly, the density of the entire area of the outer ring 392 is made uniform. Similarly, the density of each rolling element 393 is made uniform.

  The center of gravity G1 of the inner ring 391 matches the center of gravity G0 of the track ring unit 39. Similarly, the center of gravity G2 of the outer ring 392 matches the center of gravity G0 of the track ring unit 39. The rolling elements 393 are arranged at equal intervals in the circumferential direction D around the second axis B. The position of the center H of each rolling element 393 is aligned with the position of the intersection F with respect to the axial direction of the track ring unit 39.

Referring to FIG. 3, the rotor 231 of the transmission ratio variable mechanism motor 23 includes a cylindrical rotor core 85 extending in the axial direction S, and a permanent magnet 86 fixed to the outer peripheral surface of the rotor core 85.
A retained hole 87 for the second bearing 32 is formed at one end of the rotor core 85. An annular bearing holding portion 88 is provided inside the held hole 87 in the radial direction. The bearing holding portion 88 is formed on an annular convex portion 89 formed on the inner diameter portion at one end of the first housing 51. The second bearing 32 is interposed between the held hole 87 and the bearing holding portion 88. As a result, one end of the rotor core 85 is rotatably supported by the first housing 51.

  A retained hole 90 for the fourth bearing 34 is formed in an intermediate portion of the rotor core 85. An annular bearing holding portion 91 is provided inside the held hole 90 in the radial direction. The bearing holding portion 91 is formed in an annular extending portion 92 as an inner diameter portion of the second housing 52. The annular extending portion 92 has a cylindrical shape extending from the end wall 93 provided at the other end of the second housing 52 to one side S1 in the axial direction S, and the rotor core 85 is inserted therethrough.

A fourth bearing 34 is interposed between the held hole 90 and the bearing holding portion 91. Thereby, the intermediate part of the rotor core 85 is rotatably supported by the annular extending part 92 of the second housing 52. The rotor core 85 is supported at both ends by the second and fourth bearings 32 and 34.
The permanent magnet 86 of the rotor 231 has magnetic poles that are alternately different in the circumferential direction C. With respect to the circumferential direction C, N poles and S poles are alternately arranged at equal intervals. The permanent magnet 86 is externally fitted and fixed to the intermediate portion of the rotor core 85.

The stator 232 of the transmission ratio variable mechanism motor 23 is fixed to the inner peripheral surface of the first housing 51.
The motor resolver 43 includes a resolver rotor 105 and a resolver stator 106. The resolver rotor 105 is fixed to the outer peripheral surface of the other end of the rotor core 85. The resolver stator 106 is fixed to the inner peripheral surface of the cylindrical outer diameter portion 107 of the second housing 52. The outer diameter portion 107 and the annular extending portion 92 are connected via an end wall 93.

  Referring to FIG. 2, the torque sensor 44 includes a multipolar magnet 115 fixed to the intermediate portion of the second shaft 12, and is supported by one end of the third shaft 13. And a pair of magnetic yokes 116 and 117 as soft magnetic bodies which are arranged in the magnetic field, and a pair of magnetic flux collecting rings 119 and 120 for inducing magnetic flux from the magnetic yokes 116 and 117.

Each of the magnetic yokes 116 and 117 is molded on a synthetic resin member 118. The synthetic resin member 118 is coupled to one end of the third shaft 13 so as to be able to rotate together. The magnetism collecting rings 119 and 120 are molded by the synthetic resin member 121. The synthetic resin member 121 is held by the annular extending portion 92 of the second housing 52.
Magnetic flux is generated in the magnetic yokes 116 and 117 in accordance with the relative rotational amounts of the second and third shafts 12 and 13, and this magnetic flux is induced by the magnetic flux collecting rings 119 and 120, and the synthetic resin member 121. It is detected by a Hall IC (not shown) embedded in. Thereby, the magnetic flux density according to the torque applied to the second shaft 12 can be detected.

  A fifth bearing 35 is disposed on the other side S <b> 2 in the axial direction S with respect to the torque sensor 44. The end wall 93 of the second housing 52 supports the third shaft 13 via the fifth bearing 35 so as to be rotatable. The 2nd shaft 12 and the 3rd shaft 13 are mutually supported through the 6th bearing 36 so that relative rotation is possible. The end wall 61 of the third housing 53 supports the third shaft 13 through the seventh bearing 37 so as to be rotatable.

  FIG. 7A is a schematic diagram of a main part of the transmission ratio variable mechanism 5. Referring to FIG. 7A, the outer ring 392 and the inner ring 391 of the raceway ring unit 39 rotate around the first axis A by driving the rotor 231 of the transmission ratio variable mechanism motor 23. At this time, since the center of gravity G0 of the track ring unit 39 is disposed on the first axis A (motor rotation shaft), the inner ring 391, the outer ring 392, and the rolling element 393 of the track ring unit 39 do not generate vibration. .

As in the present embodiment, the input member 20 and the inner ring 391 can be magnetically engaged without contact, and the inner ring 391 and the output member 22 can be magnetically engaged without contact. The above-described configuration is possible in which the center of gravity G0 of the bearing ring unit 39 is disposed on the first axis A (motor rotation shaft).
For example, FIG. 7B shows a schematic diagram of a configuration of a main part of a comparative example having a mechanical engagement portion. In this comparative example, the input member 161 and the inner ring 153 of the raceway ring unit 151 are mechanically engaged with each other by the engagement of gears formed on the opposing end surfaces. Further, the inner ring 153 and the output member 162 are mechanically meshed with each other by meshing of gears formed on opposing end surfaces.

  In this comparative example, the center of gravity 154 and 155 of the outer ring 152 and the inner ring 153 of the bearing ring unit 151 are not arranged on the first axis 156, so that the center of gravity 157 of the bearing ring unit 151 is on the first axis 156. Not placed. In this case, the inner ring 153 and the outer ring 152 generate vibrations whose amplitude is the distance 158 between the center of gravity 157 of the track ring unit 151 and the first axis 156 in a side view.

Further, in the configuration in which the input member 161, the inner ring 153, and the output member 162 are mechanically engaged as in this comparative example, the configuration as shown in FIG. 7A, that is, the center of gravity 157 of the bearing ring unit 151 is the first. Is not physically established because the corresponding gears do not mesh well with each other.
As described above, according to the present embodiment, the centers of gravity G1 and G2 of the inner ring 391 and the outer ring 392 of the track ring unit 39 are arranged on the first axis A. Thereby, when the inner ring 391 and the outer ring 392 rotate around the second axis B, the center of gravity G1, G2 of the inner ring 391 and the outer ring 392 does not swing around the first axis A, and as a result, The rotational vibration of the inner ring 391 and the outer ring 392 can be significantly reduced.

The configuration in which the center of gravity G1 of the inner ring 391 is disposed on the first axis A allows the input member 20 and the inner ring 391 to transmit torque without contact by the first magnetic engagement mechanism 64, and the second magnetic It is possible to realize the torque transmission between the inner ring 391 and the output member 22 in a non-contact manner by the meshing mechanism 67.
The inner ring 391 is torque-transmitted in a non-contact manner by the first and second magnetic engagement mechanisms 64 and 67 corresponding to the corresponding input member 20 and output member 22, respectively. As a result, there is no mechanical contact between both the input member 20 and the inner ring 391 and between the inner ring 391 and the output member 22. Therefore, since sliding resistance can be eliminated, the transmission efficiency of the transmission ratio variable mechanism 5 can be made extremely high, and the driving sound of the transmission ratio variable mechanism 5 can be made extremely small. Therefore, the steering feeling of the steering member 2 is excellent.

  Further, since the first and second magnetic engagement mechanisms 64 and 67 are non-contact engagement mechanisms, respectively, the slip movement between the input member 20 and the inner ring 391 and the slip movement between the inner ring 391 and the output member 22 are performed. The tolerance of is high. Therefore, the degree of freedom in arrangement (alignment) between the input member 20 and the inner ring 391 can be increased, and the degree of freedom in arrangement of the inner ring 391 and the output member 22 can be increased. As a result, a layout in which the center of gravity G1 of the inner ring 391 is arranged on the first axis A can be easily realized.

Further, by providing the input member 20 with the first magnet 65 and the inner ring 391 with the second magnet 66, the input member 20 and the inner ring 391 are provided with a plurality of magnetic poles 71, 72; Yes. With such a simple configuration, the first magnetic engagement mechanism 64 can be realized.
Further, by providing the third magnet 68 on the inner ring 391 and providing the fourth magnet 69 on the output member 22, a plurality of magnetic poles 77, 78; 79, 80 are provided on each of the inner ring 391 and the output member 22. Yes. With such a simple configuration, the second magnetic engagement mechanism 67 can be realized.

Furthermore, when the transmission ratio variable mechanism motor 23 drives the inner ring 391, the transmission ratio θ2 / θ1 can be changed.
By making the transmission ratio θ2 / θ1 variable, the turning angle θ2 of the steered wheels 4L and 4R with respect to the steering of the steering member 2 can be optimized according to the traveling state of the vehicle. For example, when the vehicle is stopped or traveling at a low speed, such as when entering a garage, the transmission amount θ2 / θ1 is increased so that the steered amount of the steered wheels 4L and 4R is made larger than the steered amount of the steering member 2. The operating amount of the steering member 2 can be reduced. Further, when the vehicle is traveling on a snowy road or the like, so-called active steering can be performed in which the counter steer operation is automatically performed by the transmission ratio variable mechanism 5.

The present invention is not limited to the contents of the above-described embodiment, and various modifications can be made within the scope of the claims.
For example, the inner ring of the track ring unit is rotationally driven by a transmission ratio variable mechanism motor, the outer ring and the input member are connected by a first magnetic engagement mechanism, and the outer ring and the output member are further connected by a second magnetic member. You may connect by a meshing mechanism.

  Further, the present invention can be applied to other general oscillating gear devices other than the oscillating gear devices provided in the vehicle steering apparatus.

1 is a schematic diagram illustrating a schematic configuration of a vehicle steering apparatus including a transmission ratio variable mechanism including an oscillating gear device according to an embodiment of the present invention. It is sectional drawing which shows the more concrete structure of the principal part of FIG. FIG. 3 is an enlarged view of a transmission ratio variable mechanism in FIG. 2 and its surroundings. It is a partial cross section side view of the principal part of a transmission ratio variable mechanism. It is the side view of the principal part seen along the arrow V direction of FIG. It is the side view of the principal part seen along the arrow VI direction of FIG. (A) is a schematic diagram of the principal part of the transmission ratio variable mechanism of this Embodiment, (B) is a schematic diagram of the structure of the principal part of a comparative example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Steering device for vehicles, 2 ... Steering member, 4L, 4R ... Steering wheel, 5 ... Transmission ratio variable mechanism, 6 ... Swing-type gear apparatus, 12 ... Steering wheel side member (2nd shaft), 20 ... Input Members, 22 ... output members, 23 ... motor for transmission ratio variable mechanism (electric motor), 64 ... first magnetic engagement mechanism, 67 ... second magnetic engagement mechanism, 71, 72, 73, 74, 77, 78, 79, 80 ... magnetic poles, 201a ... opposite end of the input member, 221a ... opposite end of the output member, 391 ... inner ring (intermediate member) of the bearing ring unit, 391a ... (inner ring) Opposite end (opposite part of intermediate member), 391b (opposite part of inner ring) Opposite end part (opposite part of intermediate member), A ... first axis, B ... second axis, G1 ... (inner ring of bearing ring unit) ) Center of gravity (center of gravity of intermediate member), θ1... Steering angle (rotation angle of input member), θ2. Steering angle (rotation angle of output member), θ2 / θ1... Transmission ratio (ratio of rotation angle of output member to rotation angle of input member).

Claims (4)

An input member and an output member each having a central axis on the first axis and rotatable about the first axis; the input member and the input member so as to allow differential rotation of the input member and the output member; An intermediate member for connecting the output member,
The intermediate member has a central axis on a second axis inclined with respect to the first axis, and is rotatable around the second axis.
The center of gravity of the intermediate member is disposed on the first axis;
The input member and the intermediate member are connected via a first magnetic meshing mechanism so as to transmit torque without contact, and the intermediate member and the output member are non-contacted via a second magnetic meshing mechanism. The oscillating gear device is connected so as to be able to transmit torque. 2. The first magnetic engagement mechanism according to claim 1, wherein the first magnetic engagement mechanism is arranged in an annular shape around the central axis of each of the input member and the intermediate member at each of the opposing portions of the input member and the intermediate member, and magnetically A plurality of magnetically engageable magnetic poles,
The second magnetic engagement mechanism is arranged in an annular shape around the central axis of each of the intermediate member and the output member at each of the opposing portions of the intermediate member and the output member, and can be magnetically engaged with each other. A rocking gear device comprising a plurality of magnetic poles. The oscillating gear device according to claim 1 or 2,
An electric motor for driving the intermediate member,
A transmission ratio variable mechanism capable of changing a ratio of a rotation angle of an output member to a rotation angle of an input member. A vehicle steering apparatus capable of changing a transmission ratio, which is a ratio of a turning angle of a steered wheel to a steering angle of a steering member, using the transmission ratio variable mechanism according to claim 3,
The vehicle steering apparatus, wherein the input member is connected to a steering member, and the output member is connected to a steered wheel side member.

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