JPWO2017154133A1 - Power transmission device - Google Patents

Abstract

A power transmission device (10) disposed in a power transmission path for transmitting torque and rotation speed. At the time of torque transmission, the first roller (17) engages with the inner ring (12) and the first outer ring (15) and moves relative to the axial direction, so that a shock at the time of torque transmission can be absorbed. The restriction device (30) restricts the axial movement of the first outer ring (15) when the first roller (17) is engaged with the inner ring (12) and the first outer ring (15). Thereby, rolling of a 1st roller (17) is controlled, an increase in torque can be suppressed and torque can be cut appropriately without a sense of incongruity.

Description

  The present invention relates to a power transmission device, and more particularly to a power transmission device that cuts torque.

  There is a transmission control system that detects transmission torque to a drive wheel immediately before a shift, and reduces the transmission torque by sliding a clutch until it reaches a level corresponding to the transmission torque (Patent Document 1). In the technique disclosed in Patent Document 1, by absorbing the torque by sliding the clutch, it is possible to reduce a shift shock and accelerate the torque without interruption.

JP 2012-112396 A

  However, in the above conventional technique, the clutch is slid to absorb (cut) the torque, and if the detected value is large relative to the actual transmission torque (actual value), the clutch slip amount increases during torque transmission, and there is a sense of incongruity. There is a problem that (slip feeling) occurs. If the detected value is smaller than the actual value, the slip amount of the clutch is reduced, so that there is a problem that the amount of torque absorption is reduced and the shift shock is increased. That is, there is a possibility that the torque cannot be appropriately cut without a sense of incongruity.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide a power transmission device that can appropriately cut torque without a sense of incongruity.

Means for Solving the Problems and Effects of the Invention

  In order to achieve this object, the power transmission device according to claim 1 is arranged in a power transmission path for transmitting torque and rotational speed. Power is input to the input member, and the output member is configured to be movable relative to the input member in the axial direction. The input raceway surface of the input member and the output raceway surface of the output member are set to a predetermined taper angle. The plurality of rollers that can be engaged with or disengaged from the input member and the output member are arranged between the input raceway surface and the output raceway surface, and are set at a predetermined skew angle with respect to the central axis of the input member. The roller revolves around the central axis while rotating. At the time of torque transmission, the input member and the output member move relative to each other in the axial direction while rotating relative to each other according to the magnitude of the torque, and the rollers engage with the input member and the output member. Since torque is transmitted from the input member to the output member via the roller without slipping, the input member rotates with respect to the output member and the transmission torque increases. Since a torsional damper effect is obtained with respect to an increase in transmission torque, a shock during torque transmission can be absorbed.

  The limiting device limits axial movement of the input member or the output member when the roller, the input member, and the output member are engaged. When the movement of the input member or the output member in the axial direction is restricted by the restricting device, the rolling of the rollers between the input member and the output member is restricted, and a slip occurs between the input member and the output member and the roller. More than that, the torque does not increase. Therefore, there is an effect that the torque can be appropriately cut without a sense of incongruity.

  According to the power transmission device of the second aspect, the restriction device restricts the movement of the input member or the output member in the axial direction by the operation of the actuator. Therefore, in addition to the effect of claim 1, there is an effect that the peak torque exceeding the transmission torque can be appropriately cut by the operation of the actuator.

  According to the power transmission device of the third aspect, in the limiting mechanism, the first cam member and the second cam member that are relatively rotatable are arranged to face each other in the axial direction. The input member or the output member is coupled to the first cam member, and the second cam member is restricted from moving in the axial direction and controlled to rotate by the actuator. When the first cam member and the second cam member come into contact with each other and a thrust in the axial direction is generated by the first cam member, the friction coefficient and the cam angle are set so as to restrain each other by self-locking. Since the force for stopping the rotation of the second cam member is regulated by the self-locking of the first cam member, the actuator does not require a large output for regulating the rotation of the first cam member via the second cam member. Since the actuator only needs to have a force for controlling the second cam member to bring the first cam member and the second cam member into contact with each other or separating them, the output of the actuator can be reduced in addition to the effect of the second aspect. effective.

  According to the power transmission device of the fourth aspect, the spring biases the first cam member and the second cam member in a direction in which the first cam member and the second cam member are pressed against each other, and the actuator stops the operation of the limiting mechanism when the first cam is stopped. The second cam member is rotated so as to separate the members. In order to stop the operation of the limiting mechanism under normal conditions, the actuator rotates the second cam member so as to separate the first cam member against the force of the spring. When operating the limiting mechanism, when the actuator is stopped, the first cam member and the second cam member are pressed against each other by the spring. In addition to the effect of the third aspect, there is an effect that the first cam member and the second cam member can be constrained to each other by a spring to cut the torque.

  According to the power transmission device of the fifth aspect, since the actuator has an output that separates the first cam member and the second cam member against the force of the spring, in addition to the effect of the fourth aspect, the operation of the limiting mechanism The torque can be transmitted to the output member by stopping the operation.

  According to the power transmission device of the sixth aspect, the spring biases the first cam member and the second cam member in a direction to separate each other, and the actuator applies the first cam member when operating the limiting mechanism. The rotation of the second cam member is regulated so as to be pressed. In normal times, when the actuator is stopped, the first cam member and the second cam member are separated by the spring, so that in addition to the effect of the third aspect, the normal transmission torque can be secured by the spring.

  According to the power transmission device of the seventh aspect, since the actuator has an output that makes the first cam member and the second cam member contact each other against the force of the spring, in addition to the effect of the sixth aspect, the limiting mechanism is provided. There is an effect that the torque can be cut by operating.

  According to the power transmission device of the eighth aspect, the limiting mechanism is configured such that the first cam member and the second cam member that are relatively rotatable are arranged to face each other in the axial direction, and the first cam member, the second cam member, A rolling element that generates a thrust in the axial direction by relative rotation is disposed between the first cam member and the second cam member. The input member or the output member is coupled to the first cam member, and the actuator rotates the second cam member. Therefore, in addition to the effect of the second aspect, when the rotation of the first cam member is restricted by the actuator via the second cam member and the rolling element, the torque can be cut.

  According to the power transmission device of the ninth aspect, the limiting mechanism is formed in the first rotating body and the second rotating body in which the inclined surfaces facing each other in the axial direction are relatively rotatable, and the inclined surface is the first rotating body. A thrust in the axial direction is generated by the relative rotation of the second rotating body. The input member or the output member is coupled to the first rotating body, and the actuator rotationally drives the second rotating body. Therefore, in addition to the effect of the second aspect, when the rotation of the first rotating body is restricted by the actuator via the second rotating body, there is an effect that the torque can be cut.

It is a mimetic diagram of the vehicles carrying the power transmission device in a 1st embodiment. It is sectional drawing of the power transmission device typically shown. It is a perspective view of an inner ring and a cage showing arrangement of the first roller. (A) is a schematic diagram of the limiting mechanism when torque is transmitted, and (b) is a schematic diagram of the limiting mechanism when cutting torque. It is sectional drawing which illustrated typically the power transmission device in 2nd Embodiment. (A) is a schematic diagram of the limiting mechanism when torque is transmitted, and (b) is a schematic diagram of the limiting mechanism when cutting torque. It is a schematic diagram of the limiting mechanism of the power transmission device in the third embodiment. It is a schematic diagram of the limiting mechanism of the power transmission device in the fourth embodiment.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. A vehicle 1 equipped with a power transmission device 10 according to a first embodiment of the present invention will be described with reference to FIG. In the vehicle 1, a clutch 4 that connects and disconnects the driving force of the engine 3 is disposed in a power transmission path between the engine 3 mounted on the vehicle body 2 and the transmission 5. The output of the transmission 5 is transmitted to the drive wheels 8 via the propeller shaft 6 and the differential device 7. The driving wheel 8 and the driven wheel 9 support the vehicle body 2. A power transmission device 10 that cuts torque is disposed in a power transmission path between the engine 3 and the transmission 5.

  FIG. 2 is a cross-sectional view of the power transmission device 10 schematically shown (one-side cross-sectional view of the whole cut into ¼ by a cut surface including the central axis O). The power transmission device 10 outputs power to the inner ring 12 (input member) that rotates integrally with the input shaft 11 to which the driving force of the engine 3 (see FIG. 1) is input, and the transmission 5 (see FIG. 1). A first outer ring 15 (output member) that rotates integrally with the shaft 14, a first roller 17 that is interposed between the inner ring 12 and the first outer ring 15, and a restriction device that restricts axial movement of the first outer ring 15. 30.

  The inner ring 12 is a member that bears a function for transmitting the power of the input shaft 11, and an input raceway surface 13 that forms a single leaf rotation hyperboloid around the central axis O is formed on the outer peripheral surface. The inner ring 12 is restricted from rotating with respect to the input shaft 11 by a spline and is also restricted from moving in the axial direction with respect to the input shaft 11 by a retaining ring.

  The first outer ring 15 is a member responsible for the function of transmitting the power of the input shaft 11 to the output shaft 14 together with the inner ring 12, and the output raceway surface 16 forming a single lobe hyperboloid around the central axis O is formed on the inner peripheral surface. Is formed. The first outer ring 15 is disposed on the outer side in the radial direction of the inner ring 12, and is coupled to the output shaft 14 via the moving member 19.

  The moving member 19 is a member for transmitting the power of the first outer ring 15 to the output shaft 14 and moving the first outer ring 15 in the axial direction. The moving member 19 is integrated with the first outer ring 15 by a retaining ring. The movement member 19 is restricted from rotating with respect to the output shaft 14 by the ball spline and is allowed to move in the axial direction with respect to the output shaft 14. The input raceway surface 13 of the inner ring 12 and the output raceway surface 16 of the first outer ring 15 face each other in the axial direction and increase in diameter as they approach the moving member 19 side in the axial direction.

  FIG. 3 is a perspective view of the inner ring 12 and the cage 18 showing the arrangement of the first rollers 17. The first roller 17 is a member formed in a cylindrical shape, and a plurality of first rollers 17 are held between the input raceway surface 13 (see FIG. 2) and the output raceway surface 16 by the cage 18. The cage 18 holds the first rollers 17 spaced apart from each other so that the first rollers 17 can rotate smoothly without interfering with each other.

  The first roller 17 is inclined by a certain angle α with respect to the plane including the central axis O (set to a constant skew angle α with respect to the central axis O), and the outer circumference of the input raceway surface 13 and the output raceway surface 16. It arrange | positions in the circumferential direction of the input track surface 13 and the output track surface 16 so that a surface can contact linearly (line contact). The skew angle α of the first roller 17 and the taper angle 2β (see FIG. 2) of the input raceway surface 13 and the output raceway surface 16 are the inner ring 12 and the first outer ring 15 when power is transmitted from the input shaft 11 to the output shaft 14. When the first roller 17 is engaged and the power is transmitted from the output shaft 14 to the input shaft 11, the engagement between the inner ring 12 and the first outer ring 15 and the first roller 17 is set.

  Since the inner ring 12 is restricted from moving in the axial direction, when the first roller 17 is engaged and screwed into the inner ring 12 and the first outer ring 15, the axial direction between the input raceway surface 13 and the output raceway surface 16 is increased. The first outer ring 15 moves in the axial direction (left side in FIG. 2) with the moving member 19 so that the distance becomes smaller. The radius and mass of the first outer ring 15 and the first roller 17 are set smaller than the radius and mass of the clutch 4 (see FIG. 1). Therefore, the inertia generated by the rotational motion of the first outer ring 15 and the first roller 17 is smaller than the inertia generated by the rotational motion of the clutch 4.

  Returning to FIG. The rotary plate 20 is a disk-shaped portion that projects outward in the radial direction of the input shaft 11 and is integrated with the input shaft 11. The rotating plate 20 is a member for supporting the second outer ring 21 so as to be movable in the axial direction and immovable in the circumferential direction. The rotating plate 20 is disposed on the opposite side of the moving member 19 in the axial direction across the inner ring 12.

  The second outer ring 21 is a member having a function of transmitting the power of the output shaft 14 to the input shaft 11 together with the first outer ring 15, and is disposed on the outer side in the radial direction of the first outer ring 12. The second outer ring 21 has an output raceway surface 22 forming a single leaf rotation hyperboloid around the central axis O on the inner peripheral surface. An input raceway surface 23 facing the output raceway surface 22 of the second outer ring 21 is formed on the outer peripheral surface of the first outer ring 15. The input raceway surface 23 is a single leaf hyperboloid around the central axis O. The input raceway surface 23 of the first outer ring 15 and the output raceway surface 22 of the second outer ring 21 face each other in the axial direction and increase in diameter as they move away from the moving member 19 in the axial direction. A second roller 24 is interposed between the input raceway surface 23 of the first outer ring 15 and the output raceway surface 22 of the second outer ring 21.

  Similarly to the first roller 17, the second roller 24 is disposed so as to be inclined by a certain angle with respect to the surface including the central axis O (set to a constant skew angle with respect to the central axis O), and the input track surface. 23 and the output raceway surface 22 are formed in a cylindrical shape whose outer peripheral surface is in linear contact (line contact). The skew angle of the second roller 24 and the taper angle 2γ of the input raceway surface 23 and the output raceway surface 22 when the power is transmitted from the input shaft 11 to the output shaft 14, the first outer ring 15, the second outer ring 21, and the second roller. The second roller 24 is set to be engaged with the first outer ring 15 and the second outer ring 21 when the engagement with the output shaft 14 is released and power is transmitted from the output shaft 14 to the input shaft 11.

  The disc spring 25 is a member for urging the first outer ring 15 in a direction to reduce the axial distance between the input raceway surface 13 of the inner ring 12 and the output raceway surface 16 of the first outer ring 15. And the end face of the first outer ring 15. The disc spring 26 is a member for urging the second outer ring 21 in a direction to reduce the axial distance between the input raceway surface 23 of the first outer ring 15 and the output raceway surface 22 of the second outer ring 21. It is disposed between the plate 20 and the second outer ring 21.

  The restriction device 30 is a device for restricting the movement in the axial direction of the moving member 19 to which the first outer ring 15 is coupled. When the first roller 17 is engaged and screwed between the input raceway surface 13 of the inner ring 12 and the output raceway surface 16 of the first outer ring 15, the restriction device 30 is moved through the first member via the moving member 19. The movement of the outer ring 15 in the axial direction is appropriately stopped. As a result, torque exceeding a certain level can be prevented from being transmitted, so that the torque can be appropriately cut. The restriction device 30 includes a restriction mechanism 31 and an actuator 40 that operates the restriction mechanism 31.

  The limiting mechanism 31 includes a first cam member 32 that is coupled to the moving member 19 and rotates integrally, and a second cam member 35 that is coupled to the gear 39 and rotates integrally. The first cam member 32 and the second cam member 35 are annular members that are disposed to face each other in the axial direction and are relatively rotatable around the central axis O. The gear 39 is a member that rotates around the central axis O as the second cam member 35 rotates, and is restricted from moving in the axial direction. The actuator 40 is a device that applies a rotational driving force to the second cam member 35 via the gear 39, and includes a motor 41 and a pinion 42 that is rotated by the motor 41 and meshes with the gear 39.

  FIG. 4 is a schematic diagram showing the operation of the limiting mechanism 31. 4A is a schematic diagram of the limiting mechanism 31 when the power transmission device 10 transmits torque, and FIG. 4B is a schematic diagram of the limiting mechanism 31 when the power transmission device 10 cuts torque. is there.

  As shown in FIG. 4A, the first cam member 32 includes a cam surface 33 whose end surface is inclined spirally with respect to the central axis O (see FIG. 2), and a predetermined portion in the circumferential direction with respect to the cam surface 33. And an engaging portion 34 formed on the surface. The second cam member 35 is opposed to the cam surface 33 in the axial direction, has a cam surface 36 whose end surface is inclined spirally with respect to the central axis O, and an overhanging portion 37 that projects toward the first cam member 32. And a spring 38 held by the overhanging portion 37. The spring 38 is disposed in a compressed state between the overhanging portion 37 and the engaging portion 34. The spring 38 biases the first cam member 32 and the second cam member 35 in the direction in which the first cam member 32 and the second cam member 35 rotate relative to each other and in the direction in which the cam surfaces 33 and 36 are pressed together.

  4B, when the spring 38 is restored, the urging force of the spring 38 causes the engaging portion 34 and the overhanging portion 37 to be separated and the cam surfaces 33 and 36 are pressed against each other. As a result, axial thrust is generated in the first cam member 32 and the second cam member 35. When the axial thrust is generated by the relative rotation of the first cam member 32 and the second cam member 35, the cam surfaces 33 and 36 have a friction coefficient and a cam angle (center axis O (FIG. The angle of the cam surfaces 33 and 36 with respect to a plane orthogonal to 2) is set. Specifically, the first cam member 32 and the second cam member 35 are set so that the tangent of the cam angle is smaller than the friction coefficient. Since the second cam member 35 is restricted from moving in the axial direction via a gear 39 (see FIG. 2), when the cam surfaces 33 and 36 are pressed against each other, the second cam member 35 is self-locked. The cam member 32 is restrained.

  The actuator 40 (see FIG. 2) is a device that applies a torque for separating the cam surfaces 33 and 36 to the second cam member 35 via the gear 39. The second cam member 35, in which axial thrust is generated by the first cam member 32, is applied to the first cam member 32 via the first outer ring 15 and the moving member 19 and in the rotational direction by the spring 38. A frictional force caused by the load acts at least on the cam surface 36. The actuator 40 rotates the second cam member 35 via the gear 39, and can output the cam surfaces 33, 36 apart from each other against the load in the rotational direction caused by the frictional force between the cam surfaces 33, 36. (The value obtained by multiplying the force of the spring 38 by the number of rotations).

  Next, a method for using the power transmission device 10 will be described. When power is transmitted from the engine 3 (see FIG. 1) to the drive wheels 8 via the clutch 4 and the transmission 5, the actuator 40 moves the cam surfaces 33, 36 of the first cam member 32 and the second cam member 35 to each other. Driven to rotate away. When the inner ring 12 rotates via the input shaft 11, the first roller 17 that linearly contacts the inner ring 12 and the first outer ring 15 by the urging force of the disc spring 25 revolves around the central axis O while rotating. The rotation of the first roller 17 displaces the output raceway surface 16 of the first roller 17 and the first outer ring 15 in the radial direction, and the output raceway surface 16 moves while elastically deforming in the radial direction due to the displacement.

  Since the inner ring 12 is restricted from moving in the axial direction, the first outer ring 15 rotates so as to reduce the axial distance between the input raceway surface 13 and the output raceway surface 16 according to the magnitude of the torque. However, it moves in the axial direction (direction away from the disc spring 25). As a result, the first roller 17 is engaged with the inner ring 12 and the first outer ring 15, and power is transmitted from the inner ring 12 to the first outer ring 15. The first roller 17 engages with the inner ring 12 and the first outer ring 15 without slipping, and torque is transmitted from the inner ring 12 to the first outer ring 15 via the first roller 17. 12 rotates and the transmission torque increases. Since a torsional damper effect is obtained with respect to an increase in transmission torque, a shock during torque transmission can be absorbed. Even if the second outer ring 21 rotates via the input shaft 11 and the rotating plate 20, the second roller 24 cannot be engaged with the first outer ring 15 and the second outer ring 21.

  Since the moving member 19 and the first cam member 32 are coupled to the first outer ring 15, the moving member 19 and the first cam member 32 also rotate in the axial direction as the first outer ring 15 rotates and moves in the axial direction. Move to. Since the actuator 40 is rotationally driven against the force of the spring 38 so that the cam surfaces 33, 36 of the first cam member 32 and the second cam member 35 are separated from each other, the first cam member 32 and the second cam member The first cam member 32 can be rotated and moved in the axial direction so that the second cam member 35 does not interfere with the rotation of the first cam member 32. As a result, the state in which the first roller 17 is engaged with the inner ring 12 and the first outer ring 15 continues, and thus the state in which torque is transmitted from the input shaft 11 to the output shaft 14 continues.

  When the torque transmitted from the input shaft 11 to the output shaft 14 is cut, the first cam member 32 and the second cam member 35 are rotated relative to each other by the spring 38 due to the stop of the actuator 40 or a decrease in the rotational speed, and the cam surface 33 , 36 are pressed together. When the cam surfaces 33 and 36 come into contact with each other and axial thrust is generated in the first cam member 32 and the second cam member 35, the second cam member 35 restrains the first cam member 32 by self-locking. As a result, when the movement of the moving member 19 and the first outer ring 15 in the axial direction is restricted, the axial distance between the input raceway surface 13 and the output raceway surface 16 is not further reduced, and the first roller 17 Rolling is regulated. Since slip occurs between the inner ring 12 and the first outer ring 15 and the first roller 17 and the torque does not increase any more, the limiting device 30 becomes a torque limiter. As a result, a peak torque larger than the transmission torque from the input shaft 11 to the output shaft 14 can be appropriately cut without a sense of incongruity.

  When power is input from the drive wheel 8 to the power transmission device 10 via the transmission 5 such as coasting of the vehicle 1, the power is transmitted from the output shaft 14 to the first outer wheel 15 via the moving member 19. The When the first outer ring 15 is driven, the first roller 17 cannot be engaged with the inner ring 12 and the first outer ring 15, but the second roller 24 is engaged with the first outer ring 15 and the second outer ring 21. Thereby, the torque of the output shaft 14 is transmitted to the input shaft 11 via the first outer ring 15, the second roller 24 and the rotating plate 20.

  As described above, since the power transmission device 10 includes the limiting device 30, the rotation of the second cam member 35 can be controlled by the actuator 40. When the cam surfaces 33, 36 come into contact with each other and axial thrust is generated in the first cam member 32 and the second cam member 35, the force by which the actuator 40 stops the rotation of the second cam member 35 is applied to the first cam member 32. Regulated by self-locking. Therefore, the actuator 40 does not need a large output for regulating the rotation of the first cam member 32 via the second cam member 35. The actuator 40 only needs to have a force that controls the second cam member 35 to bring the first cam member 32 and the second cam member 35 into contact with or away from each other. Therefore, compared with the case where the rotation of the first cam member 32 is limited only by the torque of the actuator, an inexpensive and small actuator 40 having a small rated output can be employed.

  The first cam member 32 is restrained by the second cam member 35 being pressed by the spring 38 when the actuator 40 is stopped or the rotational speed is decreased. Therefore, the torque transmitted from the input shaft 11 to the output shaft 14 can be cut by regulating the first cam member 32 by the spring 38 without using the power of the actuator 40 or with the small power of the actuator 40.

  Since the inertia generated by the rotational motion of the first outer ring 15 and the first roller 17 is smaller than the inertia generated by the rotational motion of the clutch 4, a technique for sliding the clutch to cut the torque (prior art disclosed in Patent Document 1) Compared to technology, shock due to inertia change when cutting torque can be suppressed.

  Next, a second embodiment will be described with reference to FIGS. In the first embodiment, the case where the actuator 40 is driven when the operation of the limiting mechanism 31 is stopped (when normal torque is transmitted) has been described. On the other hand, in the second embodiment, a case will be described in which the actuator 62 is driven when the limiting mechanism 52 is operated (when the torque is cut). In addition, about the part same as the part demonstrated in 1st Embodiment, the same code | symbol is attached | subjected and the following description is abbreviate | omitted. FIG. 5 is a cross-sectional view schematically showing the power transmission device 50 according to the second embodiment. FIG. 6A is a schematic diagram of the limiting mechanism 52 when transmitting torque, and FIG. 6B is a schematic diagram of the limiting mechanism 52 when cutting torque.

  The power transmission device 50 includes a limiting device 51 that limits the movement in the axial direction of the moving member 19 to which the first outer ring 15 is coupled. The limiting device 51 includes a limiting mechanism 52 and an actuator 62 that operates the limiting mechanism 52. The limiting mechanism 52 includes a first cam member 53 that is coupled to the moving member 19 and rotates integrally, and a second cam member 58 that is coupled to the rotor 61 and rotates integrally. The first cam member 53 and the second cam member 58 are annular members that are disposed to face each other in the axial direction and can be relatively rotated around the central axis O. The rotor 61 is an annular member that rotates about the central axis O, and movement in the axial direction is restricted. The actuator 62 is a device that applies a braking force to the second cam member 58 via the rotor 61, and includes a hydraulic braking device 63 and a pad 64 that is pressed against the rotor 61 by the braking device 63.

  As shown in FIG. 6A, the first cam member 53 includes a cam surface 54 whose end surface is inclined spirally with respect to the central axis O (see FIG. 5), and a predetermined portion in the circumferential direction with respect to the cam surface 54. , A protruding portion 56 that protrudes toward the second cam member 58 with a gap in the circumferential direction, and a spring 57 held by the protruding portion 56. The second cam member 58 is positioned between the cam surface 59 that is opposed to the cam surface 54 in the axial direction and has an end surface spirally inclined with respect to the central axis O, and the first cam. And an engaging portion 60 projecting toward the member 53 side. The spring 57 is disposed in a compressed state between the projecting portion 56 and the engaging portion 60.

  The spring 57 biases the first cam member 53 and the second cam member 58 in the direction in which the first cam member 53 and the second cam member 58 rotate relative to each other and in the direction in which the cam surfaces 54 and 59 are separated from each other. The actuator 62 has an output (a value obtained by multiplying the force of the spring 57 by the number of rotations) that makes the first cam member 53 and the second cam member 58 contact each other against the force of the spring 57.

  In a state where the second cam member 58 is not braked by the actuator 62 via the rotor 61, the engaging portion 60 comes into contact with the stopper 55 due to the urging force of the spring 57, and the cam surfaces 54, 59 are separated. Is provided with an axial gap. In this state, no axial thrust is generated in the first cam member 53 and the second cam member 58, so the first cam member 53 and the second cam member 58 engage between the stopper 55 and the overhanging portion 56. The relative rotation is possible within the range in which the portion 60 can move. In this state, the first cam member 53 and the second cam member 58 rotate integrally.

  When the second cam member 58 is braked by the actuator 62 via the rotor 61 in a state where the first cam member 53 and the second cam member 58 rotate integrally, the first cam member 53 and the second cam member 58 rotates relative to each other and the cam surfaces 54 and 59 are pressed against each other. As a result, axial thrust is generated in the first cam member 53 and the second cam member 58. The cam surfaces 54 and 59 are set with a friction coefficient and a cam angle (an angle with respect to a plane orthogonal to the central axis O (see FIG. 5)) so as to restrain each other by self-locking at that time. Since the second cam member 58 is restricted from moving in the axial direction via the rotor 61, when the cam surfaces 54 and 59 are pressed against each other, the second cam member 58 restrains the first cam member 53 by self-locking. To do.

  The second cam member 58 in which axial thrust is generated by the first cam member 53 is caused by an axial load acting on the first cam member 53 via the first outer ring 15 (see FIG. 5) and the moving member 19. The frictional force to act acts on the cam surface 59 at least. The spring 57 rotates the second cam member 58 against a load in the rotational direction caused by the frictional force between the cam surfaces 54 and 59 when no braking force is input from the actuator 62 to the second cam member 58. It has an elastic force that can.

  Next, a method for using the power transmission device 50 will be described. When power is transmitted from the engine 3 (see FIG. 1) to the drive wheels 8 via the clutch 4 and the transmission 5, the actuator 62 is turned off so that the second cam member 58 can freely rotate. When torque is transmitted from the inner ring 12 to the first outer ring 15 via the first roller 17, the moving member 19 and the first cam member 53 rotate while the first outer ring 15 rotates and moves in the axial direction. Move in the direction. As shown in FIG. 6A, since the cam surfaces 54 and 59 of the first cam member 53 and the second cam member 58 are separated from each other, the first cam member 53 and the second cam member 58 rotate integrally. The second cam member 58 can prevent the first cam member 53 from rotating and moving in the axial direction. As a result, the state in which the first roller 17 is engaged with the inner ring 12 and the first outer ring 15 continues, and thus the state in which torque is transmitted from the input shaft 11 to the output shaft 14 continues.

  When cutting the peak torque transmitted from the input shaft 11 to the output shaft 14, the actuator 62 is driven to apply a braking force to the second cam member 58 via the rotor 61. When the cam surface 54 of the first cam member 53 and the cam surface 59 of the second cam member 58 are pressed against each other in the axial direction, axial thrust is generated in the first cam member 53 and the second cam member 58. The second cam member 58 restrains the first cam member 53 by the lock. When the first cam member 53 is restrained, the movement of the moving member 19 and the first outer ring 15 in the axial direction is restricted, so that a peak torque larger than the transmission torque transmitted from the input shaft 11 to the output shaft 14 can be cut. Since the power transmission device 50 turns off the actuator 62 when transmitting torque and drives the actuator 62 when cutting torque, energy for driving the actuator 62 can be saved.

  Next, a third embodiment will be described with reference to FIG. In the first embodiment and the second embodiment, the case where the limiting mechanisms 31 and 52 are restrained by self-locking has been described. On the other hand, in 3rd Embodiment, the power transmission device 70 which restrains the limitation mechanism 72 with the actuator 79 is demonstrated. In addition, about the part same as the part demonstrated in 1st Embodiment, the same code | symbol is attached | subjected and the following description is abbreviate | omitted. FIG. 7 is a schematic diagram of a power transmission device 70 according to the third embodiment. In FIG. 7, illustration of the first outer ring 15 and the like coupled to the moving member 19 is omitted.

  The power transmission device 70 includes a limiting device 71 that limits the movement in the axial direction of the moving member 19 to which the first outer ring 15 (see FIG. 2) is coupled. The limiting device 71 includes a limiting mechanism 72 and an actuator 79 that operates the limiting mechanism 72. The limiting mechanism 72 includes a first cam member 73 that is coupled to the moving member 19 and rotates integrally, and a second cam member 76 that is coupled to the gear 78 and rotates integrally. The first cam member 73 and the second cam member 76 are annular members that are disposed to face each other in the axial direction and can be relatively rotated around the central axis O. The gear 78 is an annular member that rotates about the central axis O, and movement in the axial direction is restricted. The actuator 79 is a device that applies torque to the second cam member 76 via the gear 78, and includes a motor 80 and a pinion 81 that is rotated by the motor 80 and meshes with the gear 78.

  The first cam member 73 includes a cam surface 74 whose end surface is inclined spirally with respect to the central axis O (see FIG. 2). The second cam member 76 includes a cam surface 77 facing the cam surface 74 in the axial direction and having an end surface spirally inclined with respect to the central axis O. A spherical rolling element 75 is sandwiched between the cam surfaces 74 and 77. The first cam member 73 and the second cam member 76 generate axial thrust via the rolling elements 75.

  In a state where the second cam member 76 is not driven by the actuator 79 via the gear 78, no axial thrust is generated in the first cam member 73 and the second cam member 76, so the first cam member 73 and the second cam The member 76 rotates integrally. Since the moving member 19 can move in the axial direction, the state where the first roller 17 is engaged with the inner ring 12 (see FIG. 2) and the first outer ring 15 is maintained, and torque can be transmitted from the input shaft 11 to the output shaft 14.

  When the second cam member 76 is driven by the actuator 79 via the gear 78, the first cam member 73 and the second cam member 76 are relatively rotated and pressed in the axial direction via the rolling element 75. Thereby, axial thrust is generated in the first cam member 73 and the second cam member 76. Since the second cam member 76 restrains the first cam member 73 and restricts the movement of the moving member 19 in the axial direction, the torque transmitted from the input shaft 11 (see FIG. 2) to the output shaft 14 can be cut.

  Next, a fourth embodiment will be described with reference to FIG. In the third embodiment, the case where the rolling element 75 is interposed between the first cam member 73 and the second cam member 76 has been described. On the other hand, in 4th Embodiment, the power transmission device 90 with which the 1st rotary body 93 and the 2nd rotary body 95 contact | connect directly is demonstrated. In addition, about the part same as the part demonstrated in 1st Embodiment and 3rd Embodiment, the same code | symbol is attached | subjected and the following description is abbreviate | omitted. FIG. 8 is a schematic diagram of a power transmission device 90 according to the fourth embodiment. In FIG. 9, illustration of the first outer ring 15 and the like coupled to the moving member 19 is omitted.

  The power transmission device 90 includes a limiting device 91 that limits the axial movement of the moving member 19 to which the first outer ring 15 (see FIG. 2) is coupled. The limiting device 91 includes a limiting mechanism 92 and an actuator 79 that operates the limiting mechanism 92. The limiting mechanism 92 includes a first rotating body 93 that is coupled to the moving member 19 and rotates integrally, and a second rotating body 95 that is coupled to the gear 78 and rotates integrally. The first rotator 93 and the second rotator 95 are annular members that are arranged to face each other in the axial direction and are relatively rotatable around the central axis O. The first rotating body 93 includes an inclined surface 94 whose end surface is inclined with respect to the central axis O (see FIG. 2). The second rotating body 95 includes an inclined surface 96 that faces the inclined surface 94 in the axial direction and has an end surface inclined with respect to the central axis O. The first rotating body 93 and the second rotating body 95 are brought into contact with the inclined surfaces 94 and 96 to generate axial thrust.

  In the state where the second rotator 95 is not rotationally driven by the actuator 79 via the gear 78, no axial thrust is generated in the first rotator 93 and the second rotator 95. The rotating body 95 rotates integrally. Since the moving member 19 can move in the axial direction, the state where the first roller 17 is engaged with the inner ring 12 (see FIG. 2) and the first outer ring 15 is maintained, and torque can be transmitted from the input shaft 11 to the output shaft 14.

  When the second rotating body 95 is rotationally driven by the actuator 79 via the gear 78, the first rotating body 93 and the second rotating body 95 are relatively rotated, and the inclined surfaces 94 and 96 are pressed in the axial direction. Thereby, axial thrust is generated in the first rotating body 93 and the second rotating body 95. Since the second rotating body 95 restrains the first rotating body 93 and restricts the movement of the moving member 19 in the axial direction, the torque transmitted from the input shaft 11 (see FIG. 2) to the output shaft 14 can be cut.

  The present invention has been described above based on the embodiments. However, the present invention is not limited to the above embodiments, and various improvements and modifications can be made without departing from the spirit of the present invention. It can be easily guessed. For example, the number of first rollers 17, the skew angle α, the inclination of the input raceway surfaces 13 and 23 and the output raceway surfaces 16 and 22 with respect to the center axis O can be set as appropriate.

  In the above embodiments, the power transmission devices 10, 50, 70, and 90 mounted on the automobile have been described. However, the present invention is not necessarily limited to this. It is naturally possible to mount the power transmission devices 10, 50, 70, 90 on other vehicles. Other vehicles include construction machinery, industrial vehicles, agricultural machinery, and the like.

  In each of the above-described embodiments, the case where the power transmission device 10, 50, 70, 90 is arranged in addition to the clutch 4 in the power transmission path between the engine 3 and the transmission 5 has been described. It is not a thing. It is naturally possible to provide power transmission devices 10, 50, 70, 90 in place of the clutch 4 in the power transmission path between the engine 3 and the transmission 5 by adding a damper mechanism or the like. Further, the power transmission devices 10, 50, 70, 90 are not provided between the engine 3 and the transmission 5, but between the engine 3 and the clutch 4, between the transmission 5 and the propeller shaft 6, and the propeller shaft. Naturally, it is possible to provide the power transmission devices 10, 50, 70, 90 in any power transmission path, such as between 6 and the differential device 7. In this case as well, the same effects as those of the above embodiments can be realized.

  In the above embodiments, the power transmission devices 10, 50, 70, 90 in which the inner ring 12 is coupled to the input shaft 11 and the first outer ring 15 is coupled to the output shaft 14 have been described. However, the present invention is not necessarily limited thereto. . Of course, it is possible to provide an outer ring (input member) coupled to the input shaft 11 and an inner ring (output member) coupled to the output shaft 14, and to provide a plurality of rollers between the outer ring and the inner ring.

  In each of the above embodiments, the case where the moving member 19 is coupled to the first outer ring 15 (output member) and the movement of the moving member 19 in the axial direction is restricted by the restriction devices 30, 51, 71, 91 has been described. It is not limited to this. On the contrary, when the movement of the first outer ring 15 in the axial direction is restricted and the inner ring 12 can be moved in the axial direction, a moving member is coupled to the inner ring 12 (input member), and the axis of the moving member It is naturally possible to restrict the movement in the direction with the restriction devices 30, 51, 71, 91.

  In each of the above-described embodiments, the case where the input raceway surfaces 13 and 23 and the output raceway surfaces 16 and 22 are formed as single lobe hyperboloids and the cylindrical first roller 17 and the second roller 24 are employed has been described. Of course, the input raceway surfaces 13 and 23, the output raceway surfaces 16 and 22, the first roller 17 and the second roller 24 in other forms can be adopted. As other forms, for example, the input raceway surfaces 13 and 23 and the output raceway surfaces 16 and 22 are made into a single-leaf rotating hyperboloid, and the first roller 17 and the second roller 24 are conical, the input raceway surfaces 13 and 23 and The output raceway surfaces 16 and 22 are conical, the input raceway surfaces 13 and 23 or the output raceway surfaces 16 and 22 are cylindrical, the first roller 17 and the second roller 24 are drum-like, drum-like, The thing etc. which make it columnar shape etc. are mentioned.

  Although the case where the gear 39 coupled to the second cam member 35 is driven by the actuator 40 has been described in the first embodiment, the present invention is not necessarily limited thereto. For example, the first cam member 32 can be a worm wheel and the second cam member 35 can be a worm. The worm wheel rotates about the center axis O, and the worm rotates about the rotation axis (axis orthogonal to the center axis O). In this case, the second cam member 35 (worm) can be directly driven by the motor 41 (actuator 40) without the spring 38, the gear 39, the pinion 42, and the like. By reducing the advance angle of the worm (second cam member 35), the second cam member is moved from the first cam member 32 (worm wheel) by self-lock when thrust in the axial direction (center axis O direction) is generated. Transmission of rotation to 35 (worm) can be made difficult. Thereby, even if it does not drive the motor 41 (actuator 40), rotation of the 1st cam member 32 (worm wheel) is blocked | prevented and the movement of the axial direction (center axis O direction) of the moving member 19 can be controlled.

  In the second embodiment, the case where the actuator 62 includes the hydraulic braking device 63 has been described. However, the present invention is not necessarily limited to this, and it is naturally possible to use a pneumatic braking device, an electromagnetic braking device, or the like. is there. The actuator 62 is not limited to the braking device 63, and it is naturally possible to replace the braking device 63 with a motor. In this case, as described in the first embodiment, a gear coupled to the second cam member 58 is provided, and a pinion that meshes with the gear is rotated by a motor. When power is transmitted from the input shaft 11 to the output shaft 14, the motor is set free, and the motor is driven by the torque input to the actuator 62 via the first cam member 53 and the second cam member 58. When cutting the torque transmitted from the input shaft 11 to the output shaft 14, the motor is driven and the first cam member 53 is restrained via the second cam member 58.

3 Engine 5 Transmission 10, 50, 70, 90 Power transmission device 12 Inner ring (input member)
15 First outer ring (output member)
17 First roller (roller)
30, 51, 71, 91 Limiting device 31, 52, 72, 92 Limiting mechanism 32, 53, 73 First cam member 35, 58, 76 Second cam member 38, 57 Spring 40, 62, 79 Actuator 75 Rolling element 93 First rotating body 94, 96 Inclined surface 95 Second rotating body α Skew angle β Taper angle O Center axis

Claims (9)

A power transmission device disposed in a power transmission path for transmitting torque and rotation speed,
An input member formed with an input raceway surface having a predetermined taper angle to which power is input;
An output member formed with an output raceway surface having a predetermined taper angle, which is configured to be relatively movable in the axial direction with respect to the input member;
The input member and the output member that are set at a predetermined skew angle with respect to the central axis of the input member and disposed between the input raceway surface and the output raceway surface are engaged or disengaged. Multiple possible rolls,
A power transmission device comprising: a restricting device that restricts movement of the input member or the output member in the axial direction when the roller is engaged with the input member and the output member.   The power transmission device according to claim 1, wherein the limiting device includes a limiting mechanism that limits movement of the input member or the output member in the axial direction and an actuator that operates the limiting mechanism. The limiting mechanism includes a first cam member and a second cam member that are disposed to face each other in the axial direction and are rotatable relative to each other.
The input member or the output member is coupled to the first cam member;
The second cam member is restricted from moving in the axial direction and controlled in rotation by the actuator,
When the first cam member and the second cam member come into contact with each other and a thrust in the axial direction is generated by the torque of the first cam member, a friction coefficient and a cam angle are set so as to restrain each other by self-locking. The power transmission device according to claim 2, wherein: A spring that biases the first cam member and the second cam member in a direction in which they are pressed against each other;
4. The power transmission device according to claim 3, wherein the actuator rotates the second cam member so as to separate the first cam member when stopping the operation of the restriction mechanism.   5. The power transmission device according to claim 4, wherein the actuator includes an output that separates the first cam member and the second cam member against the force of the spring. 6. A spring for biasing the first cam member and the second cam member in a direction to separate them from each other;
4. The power transmission device according to claim 3, wherein the actuator restricts the rotation of the second cam member so as to be pressed against the first cam member when operating the restriction mechanism. 5.   The power transmission device according to claim 6, wherein the actuator includes an output that brings the first cam member and the second cam member into contact with each other against the force of the spring. The limiting mechanism includes a first cam member and a second cam member that are disposed to face each other in the axial direction and are relatively rotatable,
A rolling element disposed between the first cam member and the second cam member that generates a thrust in an axial direction by relative rotation between the first cam member and the second cam member;
The input member or the output member is coupled to the first cam member;
The power transmission device according to claim 2, wherein the actuator rotationally drives the second cam member. The limiting mechanism includes a first rotating body and a second rotating body that are capable of relative rotation and formed with inclined surfaces facing each other in the axial direction,
The inclined surface generates a thrust in the axial direction by relative rotation of the first rotating body and the second rotating body,
The input member or the output member is coupled to the first rotating body,
The power transmission device according to claim 2, wherein the actuator rotationally drives the second rotating body.

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