JP2019163819A - Power transmission mechanism - Google Patents

Abstract

To provide a power transmission device capable of more properly suppressing resonance.SOLUTION: A power transmission device 99 has a rotation member 4, a dynamic vibration absorber 15 and a control portion 13. The dynamic vibration absorber 15 has an inertia member 152. The inertia member 152 is rotatable relative to the rotation member 4. The dynamic vibration absorber 15 converts centrifugal force received by rotation of the rotation member 4 into circumferential force in a direction to reduce relative displacement, when the relative displacement in the rotating direction occurs between the main body member 151 and the inertia member 152. The control portion 13 controls a radial position of a point of action of the circumferential force.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a power transmission device.

  A clutch device having a damper mechanism and a power transmission device such as a torque converter are installed between the drive source and the drive wheel. This power transmission device has a dynamic vibration absorber in order to prevent resonance due to vibration from a drive source.

  For example, the dynamic damper described in Patent Document 1 has a configuration that converts a centrifugal force acting on a centrifuge into a circumferential force in order to suppress a torque fluctuation peak in a wide rotational speed range.

Japanese Patent Laid-Open No. 2018-13152

  As described above, the dynamic damper device of Patent Document 1 can suppress rotational fluctuations in a wide rotational speed range. However, since the resonance frequency of the drive system varies depending on the driving state of the drive system, such as a gear position, the resonance may not be appropriately suppressed even with the dynamic damper device as described above. Then, the subject of this invention is providing the power transmission device which can suppress a resonance more appropriately.

  A power transmission device according to an aspect of the present invention is configured to transmit torque from a driving source to driving wheels. The power transmission device includes a rotating member, a dynamic vibration absorber, and a control unit. The rotating member is arranged to be rotatable by receiving torque from the drive source. The dynamic vibration absorber has an inertia member. The inertia member is rotatable relative to the rotating member. The dynamic vibration absorber is attached to the rotating member. When a relative displacement in the rotational direction occurs between the rotating member and the inertia member, the dynamic vibration absorber converts a centrifugal force received by the rotation of the rotating member into a circumferential force in a direction in which the relative displacement is reduced. The control unit controls the radial position of the point of application of the circumferential force.

  According to this configuration, the control unit can control the radial position of the point of application of the circumferential force in accordance with the resonance frequency, and thus can more appropriately suppress the resonance.

  Preferably, the dynamic vibration absorber further includes a centrifuge that receives a centrifugal force by the rotation of the rotating member.

  Preferably, the dynamic vibration absorber has a main body member, a cam follower, and a cam surface. The main body member is attached to the rotating member. The cam follower extends in the axial direction from the main body member or the inertia member. The cam surface converts the centrifugal force into a circumferential force that reduces the relative displacement when a relative displacement in the rotational direction occurs between the main body member and the inertia member. The cam follower has a shape with a different radius depending on the position in the axial direction, and is movable in the axial direction.

  Preferably, the cam follower includes a first truncated cone part and a second truncated cone part that are arranged in the axial direction and have a diameter that increases with distance from the cam follower. At least one of the first truncated cone part and the second truncated cone part is movable in the axial direction so as to approach and separate from each other.

  Preferably, the first truncated cone part and the second truncated cone part approach and separate from each other by rotating relative to each other.

  Preferably, the first truncated cone part and the second truncated cone part are screwed together.

  Preferably, the power transmission device further includes an actuator that moves the cam follower in the axial direction.

  Preferably, the actuator has a motor and a worm gear mechanism. The worm gear mechanism relatively rotates the first truncated cone part and the second truncated cone part by the rotation of the motor.

  Preferably, the power transmission device further includes a bearing member. The bearing member attaches the cam follower to the main body member or the inertia member.

  Preferably, the power transmission device further includes a housing that houses the rotating member and the dynamic vibration absorber.

  Preferably, the power transmission device further includes a rotation fluctuation detection unit that detects information about the rotation fluctuation. The control unit controls the radial position of the point of application of the circumferential force so as to reduce the rotation variation based on the information related to the rotation variation detected by the rotation variation detection unit.

  Preferably, the rotation variation detector is exposed in the housing.

  Preferably, the control unit prohibits relative rotation of the inertia member with respect to the main body member when determining that the amplitude of the rotation variation exceeds a threshold value based on the information regarding the rotation variation.

  According to the present invention, resonance can be suppressed more appropriately.

Sectional drawing of a power transmission device. The expanded sectional view of a power transmission device. The enlarged view of a dynamic vibration absorber. The expanded sectional view of a dynamic vibration absorber. The expanded sectional view of a dynamic vibration absorber. The functional block diagram of a control part. The flowchart which shows operation | movement of a control part. The expanded sectional view of the dynamic vibration damper which concerns on a modification. The expanded sectional view of the dynamic vibration damper which concerns on a modification. The expanded sectional view of the dynamic vibration damper which concerns on a modification. The expanded sectional view of the dynamic vibration damper which concerns on a modification. The enlarged view of the dynamic vibration damper which concerns on a modification. Sectional drawing of the power transmission device which concerns on a modification. Sectional drawing of the power transmission device which concerns on a modification. Sectional drawing of the power transmission device which concerns on a modification.

Hereinafter, embodiments of a power transmission device according to the present invention will be described with reference to the drawings.
[overall structure]
FIG. 1 is a cross-sectional view of a power transmission device 99 according to an embodiment of the present invention. The power transmission device 99 includes a torque converter 100. In the following description, “axial direction” means a direction in which the rotation axis O of the torque converter 100 extends. Further, “circumferential direction” means a circumferential direction of a circle around the rotation axis O, and “radial direction” means a radial direction of the circle around the rotation axis O. The inner side in the radial direction means the side approaching the rotation axis O in the radial direction, and the outer side in the radial direction means the side away from the rotation axis O in the radial direction. Although not shown, an engine is arranged on the left side of FIG. 1, and a transmission is arranged on the right side of FIG.

  Torque converter 100 is configured to transmit torque from an engine as a drive source to drive wheels. The torque converter 100 can rotate around the rotation axis O. The torque converter 100 includes a front cover 2, an impeller 3, a turbine 4, a stator 5, a lockup device 10, and a dynamic vibration absorber 15. The power transmission device 99 includes a torque converter 100, a rotation sensor 8, a power feeding unit 11, and a control unit 13.

[Front cover 2]
The front cover 2 receives torque from the engine. The front cover 2 has a disc portion 21 and a first cylindrical portion 22. The first cylindrical portion 22 extends in the axial direction from the outer peripheral end of the disc portion 21 to the impeller 3 side.

[Impeller 3]
The impeller 3 includes an impeller shell 31, a plurality of impeller blades 32, and an impeller hub 33. An outer peripheral end portion of the impeller shell 31 is fixed to a distal end portion of the first cylindrical portion 22 of the front cover 2. For example, the impeller shell 31 is fixed to the front cover 2 by welding.

  The impeller blade 32 is fixed to the inner surface of the impeller shell 31. The impeller hub 33 is fixed to the inner peripheral portion of the impeller shell 31 by welding or the like.

  The impeller shell 31 and the front cover 2 constitute a casing 20 of the torque converter 100. The housing 20 is filled with fluid. Specifically, the casing 20 is filled with hydraulic oil. The casing 20 is arranged to be able to rotate by receiving torque from the engine.

[Turbine 4]
The turbine 4 includes a turbine shell 41, a plurality of turbine blades 42, and a turbine hub 43. The turbine 4 is rotatably arranged. The turbine 4 is disposed to face the impeller 3. The turbine 4 corresponds to the rotating member of the present invention.

  The turbine shell 41 is fixed to the turbine hub 43 by rivets 101. The turbine blade 42 is fixed to the inner surface of the turbine shell 41 by brazing or the like. A spline hole 433 is formed in the inner peripheral surface of the turbine hub 43. The transmission input shaft is spline-fitted into the spline hole 433.

[Stator 5]
The stator 5 is configured to rectify the hydraulic oil that returns from the turbine 4 to the impeller 3. The stator 5 is rotatable around the rotation axis O. The stator 5 includes a stator carrier 51 and a plurality of stator blades 52.

[Lock-up device 10]
The lockup device 10 is configured to mechanically transmit torque from the front cover 2 to the turbine hub 43 in the lockup on state. The lockup device 10 is disposed between the front cover 2 and the turbine 4 in the axial direction. Further, the lockup device 10 is disposed in the housing 20. The lockup device 10 includes a clutch unit 6 and a damper mechanism 7.

The clutch part clutch part 6 has a piston 61 and a friction material 62. The piston 61 has a disk shape. The piston 61 has a through hole at the center. The turbine hub 43 extends in the through hole of the piston 61. The space between the outer peripheral surface of the turbine hub 43 and the inner peripheral surface of the piston 61 is sealed.

  The piston 61 is disposed so as to be rotatable relative to the housing 20. The piston 61 is disposed so as to be rotatable relative to the turbine hub 43. The piston 61 is disposed so as to be movable in the axial direction. Specifically, the piston 61 can slide on the turbine hub 43 in the axial direction.

  The piston 61 has a piston main body 611 and a second cylindrical portion 612. The piston main body 611 has a disc shape and faces the disc portion 21 of the front cover 2. The second cylindrical portion 612 extends in the axial direction from the outer peripheral end of the piston main body 611. Specifically, the second cylindrical portion 612 extends in a direction away from the front cover 2 from the outer peripheral end portion of the piston main body portion 611. The outer peripheral surface of the second cylindrical portion 612 is opposed to the inner peripheral surface of the first cylindrical portion 22 of the front cover 2.

  The friction material 62 is annular. The friction material 62 is fixed to the piston 61. Specifically, the friction material 62 is fixed to the outer peripheral end portion of the piston 61. The friction material 62 is disposed so as to face the disc portion 21 of the front cover 2. The friction material 62 and the disc portion 21 of the front cover 2 face each other in the axial direction.

  The clutch portion 6 is movable in the axial direction between the friction engagement position and the release position. The clutch portion 6 frictionally engages with the housing 20 when in the friction engagement position. Specifically, when the clutch portion 6 moves in the axial direction to the front cover 2 side (left side in FIG. 1), the friction material 62 of the clutch portion 6 comes into contact with the disk portion 21 of the front cover 2. Friction engagement. As a result, the clutch portion 6 enters a friction engagement state and rotates integrally with the front cover 2. In this friction engagement state, the torque input to the front cover 2 is output from the turbine hub 43 via the lockup device 10. Thus, when the clutch part 6 exists in a friction engagement position, the lockup apparatus 10 will be in a lockup ON state.

  The clutch unit 6 releases the frictional engagement between the friction material 62 and the housing 20 when in the release position. Specifically, when the clutch portion 6 moves to the side away from the front cover 2 in the axial direction (the right side in FIG. 1), the friction material 62 of the clutch portion 6 is separated from the disc portion 21 of the front cover 2 and the friction is caused. The material 62 is not in contact with the disc portion 21. As a result, the clutch portion 6 is in a released state in which the frictional engagement between the friction material 62 and the disc portion 21 is released, and can be rotated relative to the front cover 2. In this released state, the torque input to the front cover 2 is output from the turbine hub 43 via the impeller 3 and the turbine 4. Thus, when the clutch part 6 exists in a cancellation | release position, the lockup apparatus 10 will be in a lockup-off state.

  Moreover, the clutch part 6 can take a slip state. In this slip state, in the clutch portion 6, the friction material 62 and the disc portion 21 are in contact with each other, but are frictionally engaged with a weaker force than in the friction engagement state. For this reason, the friction material 62 and the disc part 21 are frictionally engaged while slipping. In this slip state, part of the torque input to the front cover 2 is output from the turbine hub 43 via the impeller 3 and the turbine 4, and the other is output from the turbine hub 43 via the lockup device 10.

The damper mechanism damper mechanism 7 is disposed between the piston 61 and the turbine 4 in the axial direction. The damper mechanism 7 includes a drive plate 71, a driven plate 72, and a plurality of torsion springs 73.

  The drive plate 71 is formed in a disc shape, and its outer peripheral end is engaged with the piston 61. For this reason, the drive plate 71 rotates integrally with the piston 61. Further, the drive plate 71 and the piston 61 move relative to each other in the axial direction.

  The driven plate 72 is formed in a disc shape. The driven plate 72 is fixed to the turbine hub 43. Specifically, the inner peripheral end of the driven plate 72 is fixed to the turbine hub 43 by welding or the like.

  The torsion spring 73 elastically connects the drive plate 71 and the driven plate 72. Therefore, the driven plate 72 can rotate relative to the drive plate 71 within a predetermined twist angle range.

  With the above configuration, the torque input to the clutch unit 6 is output from the turbine hub 43 via the drive plate 71, the torsion spring 73, and the driven plate 72.

[Dynamic vibration absorber]
The dynamic vibration absorber 15 is disposed between the lockup device 10 and the turbine 4 in the axial direction. The dynamic vibration absorber 15 is attached to the turbine 4. Specifically, the dynamic vibration absorber 15 is attached to the turbine hub 43.

  As shown in FIGS. 2 and 3, the dynamic vibration absorber 15 includes a main body member 151, a pair of inertia members 152, a plurality of centrifuges 153, and a cam mechanism 154.

The main body member main body member 151 has a disk shape having a through hole in the center. The main body member 151 is attached to the turbine 4. Specifically, the inner peripheral end of the main body member 151 is attached to the turbine hub 43. For example, the main body member 151 and the turbine hub 43 are fixed by welding or the like.

  As shown in FIG. 3, the main body member 151 has a plurality of projecting portions 155 that project radially outward at the outer peripheral end portion. Each protrusion part 155 is arrange | positioned at intervals in the circumferential direction.

Inertia Member As shown in FIG. 2, the inertia member 152 is a ring-shaped plate. The inertia member 152 is connected to each other by a cam follower 157 described later, and sandwiches the main body member 151 and the centrifuge 153. The inertia member 152 is rotatably arranged with the main body member 151. The pair of inertia members 152 are movable in the axial direction together with first and second truncated cone portions 157a and 157b described later so as to approach and separate from each other.

  As shown in FIG. 3, the inertia member 152 can rotate relative to the main body member 151 within a range of a predetermined twist angle. In the dynamic vibration absorber 15 shown in FIG. 3, the inertia member 152 is twisted with respect to the main body member 151 by an angle θ.

The centrifuge centrifuge 153 receives a centrifugal force by the rotation of the turbine 4. Specifically, the centrifuge 153 receives a centrifugal force by the rotation of the main body member 151 that rotates integrally with the turbine 4. The centrifuge 153 can slide in the radial direction along the protruding portion 155 of the main body member 151. Specifically, the centrifuge 153 has a pair of guide rollers 156. The guide roller 156 sandwiches the protruding portion 155. As the guide roller 156 rolls on the side surface of the protrusion 155, the centrifuge 153 can move in the radial direction along the protrusion 155. For this reason, the centrifuge 153 moves outward in the radial direction by receiving a centrifugal force.

The cam mechanism cam mechanism 154 includes a cam follower 157 and a cam surface 158. The cam follower 157 extends in the axial direction from the inertia member 152. Specifically, the cam follower 157 extends between the pair of inertia members 152 in the axial direction.

  When the torque converter 100 is operated, the cam surface 158 is in contact with the cam follower 157. The cam surface 158 is formed on the outer peripheral surface of the centrifuge 153. The cam surface 158 is an arc-shaped surface with which the cam follower 157 abuts and is recessed inward in the radial direction. When the main body member 151 and the inertia member 152 rotate relative to each other, the cam follower 157 moves along the cam surface 158.

  When relative displacement (rotational phase difference) occurs in the rotational direction between the main body member 151 and the inertia member 152, the cam surface 158 causes the centrifugal force generated in the centrifuge 153 to reduce the rotational phase difference. Convert to circumferential force. Specifically, due to the centrifugal force generated in the centrifuge 153, the cam surface 158 presses the cam follower 157 radially outward and also in the circumferential direction. The cam follower 157 and the inertia member 152 move so as to return to the positions before being twisted by the circumferential force by the cam surface 158.

  The cam follower 157 has a shape with a different radius depending on the position in the axial direction. The cam follower 157 is movable in the axial direction. For this reason, when the cam follower 157 moves in the axial direction, the point where the cam follower 157 contacts the cam surface 158, that is, the radial position of the point of application of the circumferential force changes.

  As shown in FIG. 4, the cam follower 157 has a first truncated cone part 157a and a second truncated cone part 157b. The first truncated cone part 157a is attached to one inertia member 152 via a bearing member 157c, and the second truncated cone part 157b is attached to the other inertia member 152 via another bearing member 157c. Yes. Specifically, each of the pair of inertia members 152 has a stepped through hole 152a. A bearing member 157c is fitted into the large diameter portion of the stepped through hole 152a.

  Each of the first and second truncated cone parts 157a and 157b has a convex part 157d extending in the axial direction. The convex portions of the first and second truncated cone portions 157a and 157b are fitted to the inner ring of the bearing member 157c.

  The first truncated cone part 157a and the second truncated cone part 157b are arranged in the axial direction. Specifically, the first truncated cone part 157a and the second truncated cone part 157b are arranged coaxially with each other. At least one of the first truncated cone part 157a and the second truncated cone part 157b is movable in the axial direction so as to approach and separate from each other. The axial movement of the cam follower 157 described above is a concept including moving in the axial direction so that at least one of the first truncated cone part 157a and the second truncated cone part 157b approaches and separates from each other.

  The first truncated cone part 157a and the second truncated cone part 157b have shapes that increase in diameter as they move away from each other. That is, the first truncated cone part 157a has a small diameter on the second truncated cone part 157b side, and the diameter increases with distance from the second truncated cone part 157b. The second truncated cone part 157b has a small diameter on the first truncated cone part 157a side, and the diameter increases as the distance from the first truncated cone part 157a increases. For this reason, the cam follower 157 has a different radius depending on the position in the axial direction.

  The first truncated cone part 157a has a screw hole 157e that opens toward the second truncated cone part 157b and extends in the axial direction. And the 2nd truncated cone part 157b has the screw part 157f screwed together with the screw hole part 157e of the 1st truncated cone part 157a. Since the first truncated cone part 157a and the second truncated cone part 157b are screwed together in this way, the first truncated cone part 157a and the second truncated cone part 157b approach and separate from each other when they rotate relative to each other. Move in the axial direction.

[Actuator]
The power transmission device further includes an actuator 17. The actuator 17 is configured to move the cam follower 157 in the axial direction. Specifically, the actuator 17 causes the first truncated cone part 157a and the second truncated cone part 157b to approach and separate from each other by relatively rotating the first truncated cone part 157a and the second truncated cone part 157b. Move in the axial direction.

  The actuator 17 has a motor 171 and a worm gear mechanism 172. For example, the motor 171 is attached to the inertia member 152 on the side where the second truncated cone part 157b is attached.

  The worm gear mechanism 172 includes a worm wheel 172a and a worm 172b. The worm wheel 172 a is attached to the output shaft of the motor 171. The worm 172b is configured integrally with the screw portion 157f of the second truncated cone portion 157b. That is, the worm 172b is a part of the second truncated cone part 157b.

  According to this actuator 17, when the motor 171 rotates the worm 172b via the worm wheel 172a, the second truncated cone part 157b rotates relative to the first truncated cone part 157a. As a result, the first truncated cone part 157a and the second truncated cone part 157b move in the axial direction so as to approach and separate from each other.

[Rotation sensor]
As shown in FIG. 2, the rotation sensor 8 is attached to the housing 20. Specifically, the rotation sensor 8 is attached to the outer peripheral wall portion of the housing 20. That is, the rotation sensor 8 is attached to the first cylindrical portion 22 of the front cover 2.

  The rotation sensor 8 detects information related to rotation fluctuation. Specifically, the rotation sensor 8 detects information related to the rotational fluctuation of the turbine 4. The rotation sensor 8 detects the number of rotations of the turbine 4 per unit time (hereinafter simply referred to as the number of rotations). The rotation sensor 8 is constituted by, for example, a rotary encoder. The rotation sensor 8 is exposed in the housing 20. The rotation sensor 8 is disposed so as to face the detected portion 9 attached to the turbine 4. The detected portion 9 has a plurality of concave portions formed on the outer peripheral surface at intervals in the circumferential direction. The detected part 9 is, for example, a gear. The rotation sensor 8 corresponds to the rotation fluctuation detection unit of the present invention.

[Power supply unit]
The power supply unit 11 is configured to supply power to the rotation sensor 8 and the motor 171. The power feeding unit 11 includes a first power receiving unit 11a, a first power transmitting unit 11b, a second power receiving unit 11c, and a second power transmitting unit 11d. For example, the first power receiving unit 11a and the second power receiving unit 11c are configured by a power receiving coil, and the first power transmitting unit 11b and the second power transmitting unit 11d are configured by a power transmitting coil.

  The first power receiving unit 11a is electrically connected to the motor 171. For example, the first power receiving unit 11a is wired to the motor 171 with an electric wire or the like. The first power receiving unit 11 a is attached to the outer peripheral surface of the dynamic vibration absorber 15. Specifically, the first power receiving unit 11 a is attached to the outer peripheral surface of the inertia member 152.

  The first power transmission unit 11 b is attached to the inner peripheral surface of the housing 20. Specifically, the first power transmission unit 11 b is attached to the inner peripheral surface of the first tubular portion 22 of the front cover 2. The first power transmission unit 11b is arranged at a distance from the first power reception unit 11a in the radial direction. The first power transmission unit 11b is configured to transmit power to the first power reception unit 11a in a contactless manner.

  The second power receiving unit 11 c is attached to the outer peripheral surface of the housing 20. Specifically, the second power receiving unit 11 c is attached to the outer peripheral surface of the first cylindrical part 22 of the front cover 2. The second power receiving unit 11c is electrically connected to the first power transmitting unit 11b. In addition, the second power receiving unit 11 c is also electrically connected to the rotation sensor 8. For example, the second power receiving unit 11c is wired to the first power transmitting unit 11b and the rotation sensor 8 with an electric wire or the like.

  The second power transmission unit 11d is disposed outside the second power reception unit 11c in the radial direction. The second power transmission unit 11d is arranged at a distance from the second power reception unit 11c in the radial direction. The second power transmission unit 11d is attached to, for example, an inner wall surface of a housing that houses the torque converter 100. The second power transmission unit 11d is configured to transmit power to the second power reception unit 11c in a contactless manner.

  The power transmission units 11b and 11d transmit power to the power reception units 11a and 11c by wireless power feeding. Note that the wireless power feeding method between the power transmission units 11b and 11d and the power reception units 11a and 11c may be a magnetic field coupling method, an electric field coupling method, or an electromagnetic field coupling method.

[Control unit]
The control unit 13 controls the radial position of the point of application of the circumferential force. In the present embodiment, the control unit 13 moves the cam follower 157 in the axial direction to control the radial position of the contact point between the cam follower 157 and the cam surface 158.

  Specifically, as shown in FIG. 4, the control unit 13 controls the actuator 17 to rotate the second truncated cone part 157 b relative to the first truncated cone part 157 a, so that the first truncated cone part 157 a The second truncated cone part 157b is approached or separated. Since the first truncated cone part 157a and the second truncated cone part 157b have different radii in the axial direction, for example, the first truncated cone part 157a and the second truncated cone part 157b are brought close to each other from the state shown in FIG. As shown in FIG. 5, the radial position of the contact point between the cam follower 157 and the cam surface 158 moves radially inward. As a result, the centrifugal force acting on the centrifuge 153 in a state where the cam surface 158 is in contact with the cam follower 157 is reduced, and the circumferential force is also reduced.

  On the other hand, when the control unit 13 controls the actuator 17 to separate the first truncated cone part 157a and the second truncated cone part 157b from the state shown in FIG. 5, the cam follower 157 and the cam follower 157 as shown in FIG. The radial position of the contact point with the surface 158 moves outward in the radial direction. As a result, the centrifugal force acting on the centrifuge 153 in a state where the cam surface 158 is in contact with the cam follower 157 is increased, and the circumferential force is also increased.

  As shown in FIG. 6, the control unit 13 includes a radial position setting unit 131 and a cam follower control unit 132. The radial position setting unit 131 sets the radial position of the contact point where the cam follower 157 and the cam surface 158 come into contact so that the rotational fluctuation is small. Specifically, the radial position setting unit 131 calculates the rotational fluctuation based on the rotational speed of the turbine 4. Then, the radial position setting unit 131 sets the radial position of the position where the cam follower 157 and the cam surface 158 are in contact based on the calculated rotational fluctuation.

  The cam follower control unit 132 controls the actuator 17 to control the axial position of the cam follower 157 based on the setting of the radial position setting unit 131.

  For example, if the radial position of the contact point between the cam follower 157 and the cam surface 158 set by the radial position setting unit 131 is radially outside the actual position at the time of setting, the cam follower control unit 132 Moves the first truncated cone part 157a and the second truncated cone part 157b in a direction in which they are separated from each other. On the other hand, if the radial position of the contact point between the cam follower 157 and the cam surface 158 set by the radial position setting unit 131 is radially inward from the actual position at the time of setting, the cam follower control unit 132. Moves the first truncated cone part 157a and the second truncated cone part 157b in the direction in which they approach each other.

[Control method]
Next, the operation of the control unit 13 will be described. First, as shown in FIG. 7, the control unit 13 acquires the rotation speed of the turbine 4 detected by the rotation sensor 8 through wireless communication (step S1). For this wireless communication, the torque converter 100 is provided with a wireless chip and an antenna (not shown), and the control unit 13 is provided with an antenna (not shown) to perform a digital modulation or analog modulation wireless communication system. Can be built. Note that this wireless communication can also be a load modulation communication method via the first power receiving unit 11a, the first power transmitting unit 11b, the second power receiving unit 11c, and the second power transmitting unit 11d.

  Next, the control part 13 calculates the rotation fluctuation | variation of the turbine 4 based on the rotation speed of the acquired turbine 4 (step S2). For example, the control unit 13 calculates the frequency of the rotational fluctuation of the turbine 4 as the rotational fluctuation.

  Next, the control unit 13 sets the radial position of the contact point between the cam follower 157 and the cam surface 158 based on the calculated rotational fluctuation (S3). For example, the control unit 13 stores a map in which the calculated value based on the rotation variation is associated with the radial position, and sets the radial position based on this map.

  Next, the control unit 13 moves the cam follower 157 in the axial direction so that the radial position of the contact point between the cam follower 157 and the cam surface 158 becomes the position set in the process of step S3 (S4). Specifically, the control unit 13 operates the actuator 17 to relatively rotate the first truncated cone part 157a and the second truncated cone part 157b of the cam follower 157. The first truncated cone part 157a and the second truncated cone part 157b approach each other or move away from each other by rotating relative to each other, and the cam follower 157 moves in the axial direction. As a result, the radial position of the contact point between the cam follower 157 and the cam surface 158 is set.

  The above-described operation of the control unit 13 may be performed not only when the lockup device 10 is in the lockup on state but also when the lockup device 10 is in the lockup off state.

[Modification]
As mentioned above, although embodiment of this invention was described, this invention is not limited to these, A various change is possible unless it deviates from the meaning of this invention.

Modification 1
In the embodiment described above, the first truncated cone part 157a and the second truncated cone part 157b are formed with outer peripheral surfaces so that the diameter is smoothly increased. However, the first truncated cone part 157a and the second truncated cone part 157b are formed. The shape is not limited to this. For example, as shown in FIG. 8, the outer peripheral surfaces of the first truncated cone part 157a and the second truncated cone part 157b may have a shape whose diameter increases stepwise through a plurality of stepped parts.

Modification 2
In the above embodiment, the actuator 17 rotates the second truncated cone part 157b to relatively rotate the first truncated cone part 157a and the second truncated cone part 157b. However, the present invention is not limited to this. For example, as shown in FIG. 9, the actuator 17 may rotate the first truncated cone part 157a and relatively rotate the first truncated cone part 157a and the second truncated cone part 157b. In this case, the worm 172b of the worm gear mechanism 172 is a part of the first truncated cone part 157a. And the 2nd truncated cone part 157b has the screw hole part 157e, and the 1st truncated cone part 157a has the screw part 157f screwed together with the 2nd truncated cone part 157b.

Modification 3
In the above embodiment, the worm 172b is configured as a part of the second truncated cone part 157b, but is not limited thereto. For example, the worm 172b is not configured as a part of the second truncated cone part 157b, and the worm 172b and the second truncated cone part 157b may be rotatable relative to each other. In this case, the first truncated cone part 157a and the second truncated cone part 157b may not rotate relative to each other. The tip of the worm 172b is a screw portion 157f, and the first truncated cone portion 157a moves in the axial direction by rotating the worm 172b.

Modification 4
In the above-described embodiment, two truncated cone parts are provided. For example, the cam follower 157 may have one truncated cone part 157a as shown in FIG. When the one truncated cone part 157a moves in the axial direction, the radial position of the contact point between the cam follower 157 and the cam surface 158 moves. In this case, the actuator 17 has a pinion gear 172c and a rack 172d instead of the worm gear mechanism. The pinion gear 172c is attached to the output shaft of the motor 171. The pinion gear 172c meshes with the rack 172d, and the rack 172d moves in the axial direction when the pinion gear 172c rotates. Since the rack 172d is configured as a part of the truncated cone part 157a, the truncated cone part 157a moves in the axial direction when the pinion gear 172c rotates.

Modification 5
In the above embodiment, the radial position of the contact point between the cam follower 157 and the cam surface 158 is controlled by moving the cam follower 157 in the axial direction. However, the method for controlling the radial position is not limited to this. For example, the radial position of the contact point between the cam follower 157 and the cam surface 158 may be controlled by moving the cam follower 157 in the radial direction. In this case, the cam follower 157 may not have a different radius depending on the position in the axial direction.

Modification 6
As shown in FIG. 11, the outer ring 157 g of the bearing member 157 c may be formed as a part of the inertia member 152. Further, the inner ring 157h of the bearing member 157c may be formed as a part of the first truncated cone part 157a or the second truncated cone part 157b.

Modification 7
When the control unit 13 determines that the calculated amplitude of the rotational fluctuation of the turbine 4 exceeds a preset first threshold value, the control unit 13 prohibits the relative rotation of the inertia member 152 with respect to the main body member 151 of the dynamic vibration absorber 15. May be executed to stop or suppress the rotational fluctuation.

  For example, as illustrated in FIG. 12, the power transmission device 99 may further include a lock mechanism 16. The lock mechanism 16 includes an electric motor 161, a pinion gear 162, and a rack 163. When the control unit 13 determines that the amplitude of the rotational fluctuation of the turbine 4 has exceeded a preset first threshold value, the control unit 13 drives the lock mechanism 16 to move the centrifuge 153 radially outward, and the cam surface 158. To push the cam follower 157 radially outward. Thereby, the inertia member 152 is suppressed from rotating relative to the main body member 151.

Modification 8
Moreover, the control part 13 does not need to perform control by the control part 13 mentioned above, when the amplitude of the rotation fluctuation of the turbine 4 calculated is less than the 2nd threshold value set beforehand.

Modification 9
In the above embodiment, the control unit 13 controls the radial position of the center of gravity of the inertia member 152 based on the rotational speed of the turbine 4 detected by the rotation sensor 8, but is not limited to this. For example, the control unit 13 can control the radial position of the contact point between the cam follower 157 and the cam surface 158 based on the transmission speed of the transmission, the frequency of the primary vibration of the engine, and the like. For example, the control unit 13 can perform control such that the radial position is preset for each gear position.

Modification 10
Further, the control unit 13 may control the radial position of the contact point between the cam follower 157 and the cam surface 158 based on the rotation speed of the piston 61. In this case, as shown in FIG. 13, the rotation sensor 8 detects the number of rotations of the piston 61. The second cylindrical portion 612 of the piston 61 has a plurality of grooves formed at intervals in the circumferential direction so that the outer peripheral end of the drive plate 71 is engaged. For this reason, the rotation sensor 8 can detect the number of rotations of the piston 61 using the plurality of groove portions of the second cylindrical portion 612.

  Then, the control unit 13 calculates the rotational fluctuation of the piston 61 from the rotational speed of the piston 61, and controls the radial position of the contact point between the cam follower 157 and the cam surface 158 so as to reduce the rotational fluctuation. Also good.

Modification 11
As shown in FIG. 14, the control unit 13 may control the radial position of the contact point between the cam follower 157 and the cam surface 158 based on the rotational fluctuation of the turbine 4 and the piston 61. Specifically, the power transmission device 99 has two rotation sensors, a first rotation sensor 8a and a second rotation sensor 8b. The first rotation sensor 8a detects the rotation speed of the turbine 4, and the second rotation sensor 8b detects the rotation speed of the piston 61.

  And the control part 13 calculates the rotation fluctuation | variation of the turbine 4 from the rotation speed of the turbine 4 detected by the 1st rotation sensor 8a, and uses the rotation speed of the piston 61 detected by the 2nd rotation sensor 8b. Rotational fluctuation is calculated. And the control part 13 may control the radial direction position of the contact point of the cam follower 157 and the cam surface 158 based on these rotation fluctuations.

Modification 12
In the above embodiment, the rotation sensor 8 is exemplified as the rotation fluctuation detection unit that detects information related to the rotation fluctuation, but the rotation fluctuation detection unit may be another sensor. For example, as illustrated in FIG. 15, the rotation variation detection unit may be an acceleration sensor 8c. The acceleration sensor 8 c is attached to the turbine 4 and detects angular acceleration of the turbine 4.

  The control unit 13 may calculate the rotational fluctuation of the turbine 4 based on the angular acceleration of the turbine 4 detected by the acceleration sensor 8c, and may control the radial position of the contact point between the cam follower 157 and the cam surface 158. In addition, the rotation fluctuation detection unit may be a speed sensor, a displacement sensor, or the like.

Modification 13
Although the outer peripheral wall part of the housing | casing 20 is mainly comprised by the 1st cylindrical part 22 of the front cover 2, it is not limited to this in particular. For example, the impeller shell 31 may have a disc part and a cylindrical part like the front cover 2. And the outer peripheral wall part of the housing | casing 20 may be comprised by the cylindrical part of this impeller shell 31, or a housing | casing is comprised by both the 1st cylindrical part 22 of the front cover 2, and the cylindrical part of the impeller shell 31. You may comprise 20 outer peripheral wall parts.

Modification 14
The present invention can be applied not only to the torque converter described above but also to other devices to which a dynamic vibration absorber can be attached, such as a clutch device and a dual mass wheel.

Modification 15
The dynamic vibration absorber 15 is not limited to the above-described configuration, and may be, for example, a rotational speed adaptive dynamic vibration absorber using a pendulum.

13: Controller 15: Dynamic vibration absorber 17: Actuator 20: Housing 99: Power transmission device 152: Inertia member 157: Cam follower 157a: First truncated cone portion 157b: Second truncated cone portion 157c: Bearing member 158: Cam surface 171: Motor 172: Worm gear mechanism

Claims (13)

A power transmission device that transmits torque from a driving source to driving wheels,
Torque from the drive source is input, and a rotating member that is rotatably arranged;
An inertia member that can rotate relative to the rotating member, and is attached to the rotating member, and when a relative displacement in a rotating direction occurs between the rotating member and the inertia member, A dynamic vibration absorber that converts a centrifugal force received into a circumferential force in a direction in which the relative displacement is reduced;
A control unit for controlling the radial position of the point of application of the circumferential force;
A power transmission device comprising:
The dynamic vibration absorber further includes a centrifuge that receives a centrifugal force by the rotation of the rotating member.
The power transmission device according to claim 1.
The dynamic vibration absorber is
A body member attached to the rotating member;
A cam follower extending in the axial direction from one of the main body member and the inertia member;
A cam surface that converts the centrifugal force into a circumferential force in a direction in which the relative displacement is reduced when a relative displacement in the rotational direction occurs between the main body member and the inertia member;
Have
The cam follower has a shape with a different radius depending on the position in the axial direction, and is movable in the axial direction.
The power transmission device according to claim 1 or 2.
The cam follower has a first truncated cone part and a second truncated cone part that are arranged in the axial direction and formed so as to increase in diameter with distance from each other.
At least one of the first truncated cone part and the second truncated cone part is movable in the axial direction so as to approach and separate from each other.
The power transmission device according to claim 3.
The first truncated cone part and the second truncated cone part move closer to and away from each other by rotating relative to each other.
The power transmission device according to claim 4.
The first truncated cone part and the second truncated cone part are screwed together;
The power transmission device according to claim 4 or 5.
An actuator for moving the cam follower in the axial direction;
The power transmission device according to any one of claims 3 to 6.
The actuator includes a motor and a worm gear mechanism that relatively rotates the first truncated cone part and the second truncated cone part by rotation of the motor.
The power transmission device according to claim 7, which is dependent on claim 5.
A bearing member for attaching the cam follower to the main body member or the inertia member;
The power transmission device according to any one of claims 3 to 8.
A housing that houses the rotating member and the dynamic vibration absorber;
The power transmission device according to any one of claims 1 to 9.
A rotation fluctuation detecting unit for detecting information on the rotation fluctuation;
The control unit controls the radial position of the point of application of the circumferential force so as to reduce the rotation variation based on information on the rotation variation detected by the rotation variation detection unit.
The power transmission device according to claim 1.
The rotation variation detector is exposed in the housing;
The power transmission device according to claim 11, which is dependent on claim 10.
When the control unit determines that the amplitude of the rotation fluctuation exceeds a threshold based on the information on the rotation fluctuation, the control section prohibits relative rotation of the inertia member with respect to the main body member.
The power transmission device according to any one of claims 1 to 12.

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