JP6068402B2 - One-way clutch and continuously variable transmission - Google Patents

Description

  The present invention relates to a one-way clutch and a crank type continuously variable transmission including the one-way clutch.

  Continuously variable transmission equipped with a one-way clutch that converts the rotation of the input shaft connected to the engine to the reciprocating motion of the connecting rod, and further converts the reciprocating motion of the connecting rod to the rotational motion of the output shaft by the one-way clutch. Is described in Patent Document 1. The one-way clutch described in Patent Document 1 includes an outer member, an inner member, a plurality of rollers disposed between the outer member and the inner member, and a plurality of coil springs that urge each of the rollers. When the rotational speed becomes faster than the rotational speed of the inner member, the roller is engaged with the wedge portion provided between the inner peripheral surface of the outer member and the outer peripheral surface of the inner member, and the input shaft is changed to the output shaft. Torque is being transmitted. In addition, a rotating body device in which a rubber member is engaged and disposed in the recesses of both transmission members that transmit torque and the rubber member elastically deforms when the load torque exceeds the upper limit torque to perform a torque limiter action. It is described in Patent Document 2.

Japanese Patent No. 5142234 JP 2002-276775 A

  However, in the one-way clutch described in Patent Document 1, when a large torque more than a predetermined value acts between the outer member and the inner member, the roller is strongly engaged with the wedge portion, and the surface pressure at the contact portion increases. At the same time, sliding friction may occur, and the roller may be abnormally worn. In addition, due to the strong biting reaction, the roller is returned with a strong force in the direction opposite to the biting direction, and as a result, the position of the roller in the non-engaged state continuously changes over a long period of time. A condition may occur. In this unstable state, it becomes impossible to engage the roller for the next torque transmission, and there is a concern that the normal transmission of torque may be hindered.

  The objective of this invention is providing the continuously variable transmission provided with the one-way clutch which can prevent the strong biting of a rolling element and a wedge part at the time of excessive torque transmission, and this one-way clutch.

In order to achieve the above object, the invention described in claim 1
An annular outer member (for example, an outer member 22 in an embodiment described later);
An annular inner member (for example, an inner member 23 in an embodiment described later) disposed coaxially on the radially inner side of the outer member;
A plurality of rollers disposed between an inner peripheral surface of the outer member (for example, an inner peripheral surface 22a in an embodiment described later) and an outer peripheral surface of the inner member (for example, an outer peripheral surface 12a in an embodiment described later). A moving body (for example, a roller 25 in an embodiment described later);
A holding member (for example, a cage 31 in an embodiment described later) disposed between an inner peripheral surface of the outer member and an outer peripheral surface of the inner member and rotatably holding the plurality of rolling elements;
A plurality of elastic members (for example, an engagement spring 24 in an embodiment described later) held by the holding member and biasing the rolling elements in the circumferential direction,
A one-way clutch that transmits driving force by engaging the rolling elements between the inner peripheral surface and the outer peripheral surface by relative rotation of the outer member and the inner member in a predetermined direction (for example, in the embodiments described later) A one-way clutch 21),
The inner peripheral surface of the outer member is a cylindrical surface,
The outer peripheral surface of the inner member has a plurality of recesses (for example, the recesses 12b in the embodiments described later) for accommodating the rolling elements,
The concave portion is an inclined surface formed so that the distance from the inner peripheral surface of the outer member gradually decreases from the non-engagement position of the rolling element toward the engagement position (for example, in an embodiment described later) An inclined surface 12c) and a wall portion (for example, a wall portion 12d in an embodiment described later) that abuts when the rolling element is in the disengaged position, and the inclined surface and the outer member The space between the inner peripheral surface constitutes a wedge part,
The wedge portion has a radial distance (for example, described later) of a narrowed portion (for example, a narrowed portion 41 in an embodiment described later) that minimizes a radial distance between the inclined surface and the inner peripheral surface of the outer member. In this embodiment, the distance L) is narrower than the diameter of the rolling element (for example, the diameter RD in the embodiments described later), and a torque greater than or equal to a predetermined value acts between the outer member and the inner member. When the rolling element is set to move to the concave portion adjacent to the circumferential direction of the inner member through the narrowed portion,
The holding member is spaced apart in a circumferential direction between a pair of annular side plates (for example, an annular member 32 in an embodiment described later) and a pair of side plates that are fitted to the outer peripheral surface of the inner member. A plurality of pillar portions (for example, spring support members 33 in the embodiments described later) that are arranged open, and at least one inner peripheral portion of the pair of side plates engages with the recess. In addition, it has an elastic engagement part (for example, an arm part 32b in an embodiment described later) that is elastically deformable radially outward.
When a torque of a predetermined value or more acts between the outer member and the inner member, and when the rolling element passes through the constricted part, the rolling element pushes the column part, and the elastic engagement part The holding member rotates relative to the inner member by elastically deforming radially outward along the inclined surface.

The invention according to claim 2 is the invention according to claim 1,
The elastic engagement portion is an arm portion that is integrally formed with an inner peripheral portion of the side plate and extends in a cantilever shape along the circumferential direction of the side plate.

The invention according to claim 3
The one-way clutch according to claim 1 or 2 (for example, the one-way clutch 21 in an embodiment described later) is provided, and the output shaft (for example, the input shaft 11 in the embodiment described later) is shifted to rotate the output shaft ( For example, a continuously variable transmission (for example, a continuously variable transmission T in an embodiment described later) that transmits to an output shaft 12) in an embodiment described later,
An eccentric mechanism (for example, the amount of eccentricity from the axis (for example, axis L1 in the later-described embodiment) of the input shaft connected to the rotation shaft of the drive source (for example, engine E in the later-described embodiment) is variable. And an input side fulcrum (for example, an eccentric disk 18 in an embodiment described later) in which the input shaft and the eccentric mechanism rotate together.
An output side fulcrum provided on the outer member of the one-way clutch (for example, a pin 19c in an embodiment described later);
A connecting rod (for example, a connecting rod 19 in an embodiment described later) having both ends connected to the input side fulcrum and the output side fulcrum and reciprocating according to the amount of eccentricity of the eccentric mechanism;
The inner member of the one-way clutch is coupled to the output shaft so as not to be relatively rotatable.

  According to the first aspect of the present invention, when a torque greater than a predetermined value acts between the outer member and the inner member, the rolling element rotates with the holding member through the constricted portion of the wedge portion, It can move to the recessed part adjacent to the circumferential direction. For this reason, it is possible to prevent the rolling element and the wedge part from being strongly bitten during excessive torque transmission, to suppress the occurrence of surface pressure rise and wear of the rolling element, and the state of the rolling element to be unstable. Can be prevented.

  According to the invention described in claim 2, since the elastic engagement portion is an arm portion that is integrally formed with the inner peripheral portion of the side plate and extends in a cantilever shape along the circumferential direction of the side plate, Normally, the holding member is maintained in a predetermined phase with respect to the inner member, and when a torque greater than a predetermined value acts between the outer member and the inner member, it elastically deforms radially outward along the inclined surface of the recess. Thus, the holding member can be rotated relative to the inner member.

  According to the invention described in claim 3, it is possible to configure a continuously variable transmission using the one-way clutch according to claim 1 or 2, and to add a torque limiter function to the continuously variable transmission. Can do.

It is a skeleton figure of a vehicle provided with a continuously variable transmission according to the present invention. FIG. 2 is a detailed view of part II in FIG. 1. It is the III-III sectional view taken on the line (OD state) of FIG. It is the III-III sectional view taken on the line (GN state) of FIG. It is operation | movement explanatory drawing in OD state. It is operation | movement explanatory drawing in a GN state. It is a disassembled perspective view of a one-way clutch. It is operation | movement explanatory drawing of a one-way clutch. It is a figure which shows the relationship between the time at the time of steady operation, and the displacement of a roller. It is a perspective view of the holding member fitted to an inner member. (A) is a side view showing the positional relationship between the rolling element and the inner member when the rolling element is in a standby state, and (b) shows the positional relationship between the rolling element and the inner member when the rolling element is in an engaged state. Side view, (c) is a side view showing the positional relationship between the rolling element and the inner member in a state in which the rolling element is deeply engaged due to excessive torque, and (d) is a circle where the rolling element crosses the wedge portion. It is a side view which shows the positional relationship of the rolling element of the state moved to the recessed part adjacent to the circumferential direction, and an inner member. (A) is a side view showing a state in which the elastic engagement portion of the holding member is engaged with the concave portion of the inner member when the rolling element is in a standby state, and (b) is an elasticity of the holding member due to excessive torque acting. It is a side view which shows the state which an engaging part elastically deforms radially outside along the shape of a recessed part. It is a figure which shows the relationship between the relative angle of an inner member and an outer member, and transmission torque. It is a figure which shows the relationship between the time at the time of abnormal biting, and the displacement of a roller.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the vehicle power transmission device for transmitting the driving force of the engine E to the driving wheels W, W via the left and right axles 10, 10 includes a crank type continuously variable transmission T and a differential gear D. Prepare.

  Next, the structure of the continuously variable transmission T will be described with reference to FIGS.

  As shown in FIGS. 2 and 3, the continuously variable transmission T according to the present embodiment is obtained by superimposing a plurality (four in the embodiment) of transmission units U having the same structure in the axial direction. The transmission unit U includes a common input shaft 11 and a common output shaft 12 arranged in parallel. The rotation of the input shaft 11 is decelerated or increased and transmitted to the output shaft 12.

  Hereinafter, the structure of one transmission unit U will be described as a representative. The input shaft 11 connected to the engine E and rotates passes through the hollow rotating shaft 14a of the speed change actuator 14 such as an electric motor so as to be relatively rotatable. The rotor 14b of the speed change actuator 14 is fixed to the rotating shaft 14a, and the stator 14c is fixed to the casing. The rotation shaft 14 a of the speed change actuator 14 can rotate at the same speed as the input shaft 11 and can rotate relative to the input shaft 11 at a different speed.

  A first pinion 15 is fixed to the input shaft 11 passing through the rotation shaft 14 a of the speed change actuator 14, and a crank-shaped carrier 16 is connected to the rotation shaft 14 a of the speed change actuator 14 so as to straddle the first pinion 15. The Two second pinions 17, 17 having the same diameter as the first pinion 15 are supported via pinion pins 16 a, 16 a at positions forming an equilateral triangle in cooperation with the first pinion 15, respectively. The first pinion 15 and the second pinions 17, 17 mesh with a ring gear 18 a formed eccentrically inside a disc-shaped eccentric disk 18. A ring portion 19 b provided at one end of the rod portion 19 a of the connecting rod 19 is fitted to the outer peripheral surface of the eccentric disk 18 via a ball bearing 20 so as to be relatively rotatable.

  The four transmission units U share the crank-shaped carrier 16, but the phase of the eccentric disk 18 supported by the carrier 16 via the second pinions 17, 17 is 90 ° at each transmission unit U. Is different.

  A one-way clutch 21 provided on the outer periphery of the output shaft 12 is arranged inside the outer member 22 with a ring-shaped outer member 22 pivotally supported by a rod portion 19a of a connecting rod 19 via a pin 19c. And an inner member 23 fixed to the outer member 22 and a plurality of rollers 25 arranged in a wedge-shaped space formed between the outer member 22 and the inner member 23 and biased by an engagement spring 24.

  As is apparent from FIG. 2, the four transmission units U share the crank-shaped carrier 16, but the phases of the eccentric disks 18 supported by the carrier 16 via the second pinions 17 and 17 are respectively The transmission unit U is different by 90 °. For example, in FIG. 2, the eccentric disk 18 of the leftmost transmission unit U is displaced upward in the figure with respect to the input shaft 11, and the eccentric disk 18 of the third transmission unit U from the left is relative to the input shaft 11. The eccentric disks 18 and 18 of the second and fourth transmission units U and U from the left are located in the middle in the vertical direction.

  Next, the structure of the one-way clutch 21 will be described with reference to FIGS. 3 to 6, the one-way clutch 21 is schematically shown, and the actual structure is shown in FIGS.

  The one-way clutch 21 of the present embodiment basically includes twelve rollers 25 between the circular inner peripheral surface 22a of the annular outer member 22 and the outer peripheral surface 12a bent in a wave shape of the cylindrical inner member 23. The connecting rod 19 is connected to the projecting portions 22b, 22b provided on the outer periphery of the outer member 22 via the pins 19c and the clips 40, 40, and the output shaft 12 is connected to the inner peripheral portion of the inner member 23. Coupled so as not to rotate relative to each other.

  The one-way clutch 21 includes a cage 31 that is a holding member for holding the roller 25 so as to be rotatable and supporting an engagement spring 24 that biases the roller 25. The cage 31 includes a pair of annular members 32 and 32 made of an annular plate member, and twelve spring support members 33 that are arranged at equal intervals in the circumferential direction and connect the pair of annular members 32 and 32 to each other. The pair of annular members 32, 32 are arranged on both axial sides of the twelve rollers 25, and twelve spring support members 33 are arranged between the twelve rollers 25.

  On the inner peripheral portion of one annular member 32, twelve recesses 32a that are recessed radially outward are formed at intervals of 30 °. Further, twelve arm portions (elastic engagement portions) that are notched in an approximately L shape and extend in a cantilever shape along the circumferential direction of the annular member 32 are formed in the inner peripheral portion of at least one annular member 32. ) 32b is formed.

  As shown in FIG. 10, the cage 31 is externally fitted to the outer peripheral surface 12a of the inner member 23, and the arm portion 32b is engaged with a recess 12b of the inner member 23 described later. The arm portion 32b can be elastically deformed radially outward.

  As shown in detail in FIG. 8, the engagement spring 24 is configured by bending one rectangular elastic plate material so as to have a constant cross section. One end of the engagement spring 24 is formed with a fixed end 24 a that is fixed to the spring support member 33 of the cage 31, and the other end of the engagement spring 24 is a biasing end that contacts the outer peripheral surface 25 a of the roller 25. A portion 24b is formed. The fixed end 24a has a U-shaped cross section, and is fixed by being press-fitted into a spring support member 33 having a rectangular cross section.

  Specifically, the engagement spring 24 includes a fixed end portion 24a and a U-shaped portion that extends substantially linearly from the fixed end portion 24a radially inward and then curves in a substantially U-shape toward the radially outer side. 24c and a biasing end portion 24b that curves radially inward from the front end portion of the U-shaped portion 24c and contacts the outer peripheral surface 25a of the roller 25 at the end portion.

  As shown in FIG. 7, a pair of angular ball bearings 34, 34 located on both sides in the axial direction of the roller 25 are disposed between the outer member 22 and the inner member 23, and the angular ball bearing 34, 34, the outer member 22 and the inner member 23 are connected so as to be relatively rotatable while maintaining a concentric state. The angular ball bearing 34 has a plurality of balls 37 arranged between an outer ring 35 and an inner ring 36. The outer ring 35 is integrally formed at the end of the outer member 22 in the axial direction, and the inner ring 36 is constituted by a separate member for output. It is fixed to the outer periphery of the shaft 12.

  The angular ball bearings 34 are classified into a double row and a single row, and the two angular ball bearings 34 and 34 positioned at both ends in the axial direction of the four one-way clutches 21 are a single row. The three angular ball bearings 34 are shared by the two adjacent one-way clutches 21 and 21, so that they form a double row.

  An axial spring 38 is disposed between one angular ball bearing 34 and one annular member 32 of the cage 31, and a plurality of protrusions 38 a projecting from the inner periphery of the axial spring 38 are provided on the inner periphery of the annular member 32. Passing between the recesses 32 a of the roller 25, it elastically contacts the end surface of the roller 25. An annular ring spring 39 is disposed in the annular groove 22 c formed on the inner peripheral surface of the v outer member 22, and this ring spring 39 abuts on the peripheral surface of the roller 25 and the outer peripheral surface of the inner member 23. Energize towards 12a.

  Both ends of the inner member 23 are rotatably supported by the transmission case via a pair of ball bearings (not shown), and four one-way clutches 21 are disposed between the inner races of these ball bearings.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  First, the operation of one transmission unit U of the continuously variable transmission T will be described. When the rotation shaft 14 a of the speed change actuator 14 is rotated relative to the input shaft 11, the carrier 16 rotates about the axis L <b> 1 of the input shaft 11. At this time, the center O of the carrier 16, that is, the center of an equilateral triangle formed by the first pinion 15 and the two second pinions 17, 17 rotates around the axis L <b> 1 of the input shaft 11.

  3 and 5 show a state in which the center O of the carrier 16 is opposite to the output shaft 12 with respect to the first pinion 15 (that is, the input shaft 11). At this time, the eccentric disk 18 with respect to the input shaft 11 is shown. The amount of eccentricity is maximized and the ratio of the continuously variable transmission T is in the OD (overdrive) state. 4 and 6 show a state in which the center O of the carrier 16 is on the same side as the output shaft 12 with respect to the first pinion 15 (that is, the input shaft 11). The amount of eccentricity is minimized and the ratio of the continuously variable transmission T is in the GN (geared neutral) state.

  In the OD state shown in FIG. 5, when the input shaft 11 is rotated by the engine E and the rotation shaft 14 a of the speed change actuator 14 is rotated at the same speed as the input shaft 11, the input shaft 11, the rotation shaft 14 a, the carrier 16, With the one pinion 15, the two second pinions 17, 17 and the eccentric disk 18 being integrated, the pinion 15 rotates eccentrically around the input shaft 11 (see arrow A). While rotating from FIG. 5A through FIG. 5B to the state of FIG. 5C, the ring portion 19b is supported on the outer periphery of the eccentric disk 18 via the ball bearing 20 so as to be relatively rotatable. The connecting rod 19 rotates the outer member 22 pivotally supported by a pin 19c at the tip of the rod portion 19a in the counterclockwise direction (see arrow B). 5A and 5C show both ends of the rotation of the outer member 22 in the arrow B direction.

  When the outer member 22 rotates in the direction of arrow B in this way, the roller 25 is engaged in the wedge-shaped space between the outer member 22 and the inner member 23 of the one-way clutch 21, and the rotation of the outer member 22 is performed via the inner member 23. Since it is transmitted to the output shaft 12, the output shaft 12 rotates counterclockwise (see arrow C).

  When the input shaft 11 and the first pinion 15 further rotate, the eccentric disk 18 in which the ring gear 18a is engaged with the first pinion 15 and the second pinion 17, 17 rotates eccentrically in the counterclockwise direction (see arrow A). While rotating from the state shown in FIG. 5C to the state shown in FIG. 5A, the ring portion 19b is supported on the outer periphery of the eccentric disk 18 via the ball bearing 20 so as to be relatively rotatable. The connecting rod 19 rotates the outer member 22 pivotally supported by a pin 19c at the tip of the rod portion 19a in the clockwise direction (see arrow B ′). FIG. 5C and FIG. 5A show both ends of the rotation of the outer member 22 in the direction of the arrow B ′.

  When the outer member 22 rotates in the direction of the arrow B ′ in this way, the roller 25 is pushed out from the wedge-shaped space between the outer member 22 and the inner member 23 while compressing the engagement spring 24, so that the outer member 22 is The output shaft 12 does not rotate by slipping with respect to the inner member 23.

  As described above, when the outer member 22 reciprocates, the output shaft 12 rotates counterclockwise (see arrow C) only when the rotation direction of the outer member 22 is counterclockwise (see arrow B). The shaft 12 rotates intermittently.

  FIG. 6 shows the operation when the continuously variable transmission T is operated in the GN state. At this time, since the position of the input shaft 11 coincides with the center of the eccentric disk 18, the eccentric amount of the eccentric disk 18 with respect to the input shaft 11 becomes zero. In this state, when the input shaft 11 is rotated by the engine E and the rotating shaft 14a of the speed change actuator 14 is rotated at the same speed as the input shaft 11, the input shaft 11, the rotating shaft 14a, the carrier 16, the first pinion 15, 2 In a state in which the second pinions 17 and 17 and the eccentric disk 18 are integrated, the input pin 11 rotates eccentrically in the counterclockwise direction (see arrow A). However, since the eccentric amount of the eccentric disk 18 is zero, the stroke of the reciprocating motion of the connecting rod 19 is also zero, and the output shaft 12 does not rotate.

  Therefore, if the speed change actuator 14 is driven and the position of the carrier 16 is set between the OD state of FIG. 3 and the GN state of FIG. 4, operation at an arbitrary ratio between the zero ratio and the predetermined ratio becomes possible.

  In the continuously variable transmission T, the phases of the eccentric disks 18 of the four transmission units U juxtaposed are shifted by 90 ° from each other, so that the four transmission units U alternately transmit the driving force, That is, the output shaft 12 can be continuously rotated because any one of the four one-way clutches 21 is always in an engaged state.

  Next, the engaging action of the one-way clutch 21 will be described in detail with reference to FIG.

  The inner peripheral surface 22a of the outer member 22 is a cylindrical surface. In addition, on the outer peripheral surface 12a of the inner member 23 that is bent in a wavy shape, twelve concave portions 12b composed of two surfaces of the inclined surface 12c and the wall portion 12d are formed at equal intervals (30 ° intervals) in the circumferential direction. ing. The inclined surface 12c is inclined so that the distance from the inner peripheral surface 22a of the outer member 22 gradually decreases from the non-engagement position (right side in FIG. 8) of the roller 25 toward the engagement position (left side in FIG. 8). Is formed. Thereby, the space between the inclined surface 12c and the inner peripheral surface 22a of the outer member 22 forms a wedge portion.

  The radial distance L of the narrowed portion 41 of the wedge portion where the radial distance between the inclined surface 12c and the inner peripheral surface 22a of the outer member 22 is minimum is slightly narrower than the diameter RD of the roller 25 and the outer member 22 When a torque greater than a predetermined value acts between the inner member 23 and the inner member 23, the roller 25 distorted by the torque passes through the constricted portion 41 and is movable in the circumferential direction (counterclockwise in FIG. 8). . Thereby, when a torque of a predetermined value or more acts, the roller 25 moves to the recess 12b (the recess on the left side in FIG. 8) adjacent in the circumferential direction of the inner member 23.

  The wall portion 12d is a wall having a large inclination angle formed by connecting the end portion of the inclined surface 12c on the non-engagement position side and the outer peripheral surface 12a. Accordingly, the roller 25 cannot move beyond the wall portion 12d.

  As shown in FIG. 8, the roller 25 is movable relative to the outer member 22 and the inner member 23 in the circumferential direction. In the state of the roller 25, the roller 25 engages with a wedge-shaped space formed between the inner peripheral surface 22 a of the outer member 22 and the inclined surface 12 c of the inner member 23, and serves as an engagement point that can transmit driving force. When the engagement state is positioned, when the roller 25 is in a standby state positioned just before the bite-shaped space is engaged, and when the engagement of the one-way clutch 21 is released, the roller 25 changes the engagement point from the engagement point. After being pushed back in the opposite direction (non-engagement direction) beyond the engagement direction, the operation returns to the daytime point by the elastic force of the compressed engagement spring 24 and moves again in the non-engagement direction. There is a damping state in which the amplitude is attenuated. Note that, at the moment when the engagement of the one-way clutch 21 is released, the position where the roller 25 is pushed back to the maximum in the non-engagement direction beyond the daytime point is referred to as a “damping point”.

  At the time of steady operation, as shown in FIG. 8, when the outer member 22 rotates relative to the inner member 23 in the direction of arrow A when the roller 25 is in the standby state, the roller 25 receives the urging force received from the engagement spring 24 and the outer member 22. It moves in the direction of arrow A by the frictional force received from the member 22 and the inner member 23. As a result, as shown in FIG. 9, the roller 25 is engaged with each surface in a wedge-shaped space between the inner peripheral surface 22 a of the outer member 22 and the inclined surface 12 c of the inner member 23, thereby driving the driving force. Can be transmitted. When the outer member 22 rotates relative to the inner member 23 in the direction of arrow B from the engaged state, the roller 25 resists the biasing force received from the engagement spring 24 by the frictional force received from the outer member 22 and the inner member 23. Then, it moves in the direction of the arrow B and is disengaged from the inner peripheral surface 22a of the outer member 22 and the inclined surface 12c of the inner member 23, so that the engagement of the one-way clutch 21 is released and a damping state is established. When the vibration of the roller 25 is settled, the roller 25 returns to the standby state biased by the engagement spring 24.

  When the roller 25 moves in the space between the inner peripheral surface 22a of the outer member 22 and the outer peripheral surface 12a of the inner member 23 in the process of shifting from the engaged state to the damping state, the axial spring 38 shown in FIG. Since the end face of the roller 25 biased in the direction is pressed against the annular member 32 of the cage 31, the behavior of the roller 25 can be stabilized by the frictional force. Further, when the roller 25 moves in the space between the inner peripheral surface 22a of the outer member 22 and the outer peripheral surface 12a of the inner member 23, the roller 25 is applied to the inner peripheral surface 22a of the outer member 22 positioned radially outward by centrifugal force. Although it is pressed, it can be suppressed by a radially inward elastic force of the ring spring 39 shown in FIG.

  Next, a case where a torque greater than a predetermined value acts between the outer member 22 and the inner member 23 will be described with reference to FIGS.

  When a large torque acts between the outer member 22 and the inner member 23, as shown in FIG. 11 (a), the roller 25 positioned at the daytime point exceeds the normal engagement point shown in FIG. 11 (b). Thus, the inner member 23 is strongly bitten between the inclined surface 12c and the inner peripheral surface 22a of the outer member 22 (see FIG. 11C). When the torque exceeds a predetermined value, the roller 25 distorted by the torque moves through the constricted portion 41 shown in FIG. 8 and moves in the circumferential direction (counterclockwise in FIG. 11). Thus, as shown in FIG. 11D, the roller 25 moves to the concave portion 12b adjacent to the inner member 23 in the circumferential direction (the concave portion adjacent to the left in FIG. 11D).

  As shown in FIG. 12, the roller 25 that moves in the circumferential direction by a torque equal to or greater than a predetermined value abuts against the spring support member 33 of the cage 31 and pushes the cage 31 in the circumferential direction. Relative rotation in the counterclockwise direction in FIG. At this time, the arm portion (elastic engagement portion) 32b formed on the inner peripheral portion of the annular member 32 of the cage 31 follows the shape of the inclined surface 12c from the state in which it is engaged with the concave portion 12b of the inner member 23. And elastically deforms radially outward. When the roller 25 moves to the adjacent recess 12b in the circumferential direction, the arm portion 32b also engages with the adjacent recess 12b.

  When the roller 25 abuts against the spring support member 33 and rotates the cage 31, the axial length of the spring support member 33 is prevented in order to prevent the roller 25 from being damaged by the corners at both ends of the spring support member 33 in the axial direction. It is desirable to set the length longer than the axial length of the roller 25.

  Thus, when a torque of a predetermined value or more is applied to the one-way clutch 21, the roller 25 and the cage 31 rotate relative to the inner member 23 by 30 ° and move to the recesses 12b adjacent in the circumferential direction. . The roller 25 performs a normal engagement operation between the inner peripheral surface 22a of the outer member 22 and the inclined surface 12c of the inner member 23 in the concave portion 12b shifted by one step (30 °) in the circumferential direction.

  In other words, the one-way clutch 21 of the present embodiment has a torque limiter function. As shown in FIG. 13, when the outer member 22 swings, transmission is performed as the relative angle between the outer member 22 and the inner member 23 increases. The torque gradually increases (straight line N1 shown in FIG. 13). When excessive torque is input to the one-way clutch 21, the roller 25 and the cage 31 move to the adjacent recess 12b in the circumferential direction in a state where the transmission torque is kept constant at the rated torque (straight line N2 shown in FIG. 13). To do. When the roller 25 moves to the concave portion 12b adjacent in the circumferential direction, the transmission torque is reduced to a substantially zero state. Thereby, it is possible to prevent a torque greater than a predetermined value from acting on the one-way clutch 21. Therefore, an increase in surface pressure due to abnormal biting of the roller 25 is suppressed, and wear due to slippage of the roller 25 can be prevented.

  On the other hand, in a conventional one-way clutch that does not have a torque limiter function, when a torque greater than a predetermined value is applied, the roller 25 bites to a deep position beyond the engagement point shown in FIG. 8 (straight line N3 shown in FIG. 13), The roller 25 is repelled by a strong reaction force in the direction opposite to the engagement direction (non-engagement direction) due to a large reaction force due to this deep biting, and an unstable state where the damping state continues for a long time as shown in FIG. It becomes. In this state, since the position of the roller 25 does not converge to the daytime point shown in FIG. 8, the roller 25 cannot be engaged for the next torque transmission, and the subsequent normal torque transmission may be hindered. is there. However, since the one-way clutch 21 of the present embodiment has the torque limiter function as described above, the roller 25 is prevented from entering the unstable state described above, and a stable operation is maintained.

  As described above, according to the one-way clutch 21 according to the present embodiment, the inner peripheral surface 22a of the outer member 22 is a cylindrical surface, and the outer peripheral surface 12a of the inner member 23 is a plurality of recesses 12b that accommodate the rollers 25. Have The recess 12b includes an inclined surface 12c formed so that the distance from the inner peripheral surface 22a of the outer member 22 gradually decreases from the non-engagement position of the roller 25 toward the engagement position, and the roller 25 is in a non-engagement position. And a wall portion 12d that comes into contact with the inner surface 22a of the outer member 22 constitutes a wedge portion. In the wedge portion, the radial distance L of the narrowed portion 41 where the radial distance between the inclined surface 12c and the inner peripheral surface 22a of the outer member 22 is minimum is slightly narrower than the diameter RD of the roller 25, and the outer member When a torque of a predetermined value or more is applied between the inner member 23 and the inner member 23, the roller 25 distorted by the torque passes through the constricted portion 41 and moves to the concave portion 12b adjacent to the inner member 23 in the circumferential direction. Is set. The cage 31 includes a pair of annular members 32 fitted to the outer peripheral surface 12a of the inner member 23, and a plurality of springs disposed between the pair of annular members 32 at intervals in the circumferential direction. And at least one inner peripheral portion of the pair of annular members 32 has an arm portion 32b that engages with the recess 12b and is elastically deformable radially outward. When a torque of a predetermined value or more acts between the outer member 22 and the inner member 23 and the roller 25 passes through the narrowed portion 41, the roller 25 pushes the spring support member 33 and the arm portion 32b is inclined. The cage 31 rotates relative to the inner member 23 by elastically deforming radially outward along the surface 12c. As a result, when a torque greater than a predetermined value acts between the outer member 22 and the inner member 23, the roller 25 moves together with the cage 31 through the narrowed portion 41 of the wedge portion and moves to the recess 12 b adjacent in the circumferential direction. can do. For this reason, it is possible to prevent the roller 25 and the wedge portion from being strongly engaged during excessive torque transmission, to suppress the increase in the surface pressure of the roller 25 and the occurrence of wear, and to make the behavior of the roller 25 unstable. Can be prevented.

  Further, since the arm portion 32b is formed integrally with the inner peripheral portion of the annular member 32 and extends in a cantilever shape along the circumferential direction of the annular member 32, the arm portion 32b normally has the inner member 23. When the inner member 23 and the cage 31 are maintained in a predetermined phase by engaging with the concave portion 12b of the inner member 23 and a torque of a predetermined value or more is applied between the outer member 22 and the inner member 23, the inclined surface 12c of the concave portion 12b. The cage 31 can be relatively rotated with respect to the inner member 23 by being elastically deformed radially outward along.

  The continuously variable transmission T includes the above-described one-way clutch 21 and the eccentric disk 18 whose amount of eccentricity from the axis L1 of the input shaft 11 connected to the rotation shaft of the engine E is variable. The eccentric side of the eccentric disk 18 is connected to both the input side fulcrum, the output side fulcrum provided on the outer member 22 of the one-way clutch 21, and the input side fulcrum and the output side fulcrum. Accordingly, the connecting rod 19 that reciprocates in accordance with the speed of the input shaft 11 is shifted and transmitted to the inner member 23, so that the continuously variable transmission T can be provided with a torque limiter function.

  In addition, this invention is not limited to each embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably. For example, the one-way clutch 21 according to the present invention can be applied to any application other than the continuously variable transmission T. Further, the number of rollers 25 and the number of engagement springs 24 of the one-way clutch 21 are not limited to the embodiment.

11 Input shaft 12 Output shaft 12a Outer peripheral surface 12b Recessed portion 12c Inclined surface 12d Wall portion 18 Eccentric disc (Eccentric mechanism, input side fulcrum)
19 Connecting rod 19c Pin (Output side fulcrum)
21 One-way clutch 22 Outer member 22a Inner peripheral surface 23 Inner member 24 Engage spring (elastic member)
25 Roller (rolling element)
31 Cage (holding member)
32 Ring member (side plate)
32b Arm part (elastic engagement part)
33 Spring support member (column)
41 Constriction RD Diameter of rolling element E Engine (drive source)
L Distance in the radial direction of the constriction L1 Axis T of the input shaft T Continuously variable transmission

Claims (3)

An annular outer member;
An annular inner member disposed coaxially on the radially inner side of the outer member;
A plurality of rolling elements disposed between the inner peripheral surface of the outer member and the outer peripheral surface of the inner member;
A holding member that is disposed between an inner peripheral surface of the outer member and an outer peripheral surface of the inner member, and holds the plurality of rolling elements rotatably;
A plurality of elastic members held by the holding member and biasing the rolling elements in a circumferential direction;
A one-way clutch that transmits a driving force by engaging the rolling elements between the inner peripheral surface and the outer peripheral surface by relative rotation of the outer member and the inner member in a predetermined direction;
The inner peripheral surface of the outer member is a cylindrical surface,
The outer peripheral surface of the inner member has a plurality of recesses for accommodating the rolling elements,
The recess includes an inclined surface formed so that a distance from the inner peripheral surface of the outer member gradually decreases from a non-engagement position of the rolling element toward an engagement position, and the rolling element is non-engaged. A wall portion that abuts when in the mating position, and a space between the inclined surface and the inner peripheral surface of the outer member constitutes a wedge portion,
In the wedge portion, the radial distance of the constricted portion that minimizes the radial distance between the inclined surface and the inner peripheral surface of the outer member is smaller than the diameter of the rolling element, and the outer member and the outer member When a torque greater than or equal to a predetermined value acts between the inner member and the inner member, the rolling element passes through the constriction and is set to move to the recess adjacent in the circumferential direction of the inner member,
The holding member includes a pair of annular side plates that are fitted to the outer peripheral surface of the inner member, and a plurality of column portions that are arranged at intervals in the circumferential direction between the pair of side plates. And, at least one inner peripheral portion of the pair of side plates has an elastic engagement portion that engages with the concave portion and is elastically deformable radially outward,
When a torque of a predetermined value or more acts between the outer member and the inner member, and when the rolling element passes through the constricted part, the rolling element pushes the column part, and the elastic engagement part A one-way clutch in which the holding member rotates relative to the inner member by elastically deforming radially outward along the inclined surface. The one-way clutch according to claim 1,
The one-way clutch, wherein the elastic engagement portion is an arm portion that is integrally formed with an inner peripheral portion of the side plate and extends in a cantilever shape along a circumferential direction of the side plate. A continuously variable transmission comprising the one-way clutch according to claim 1 or 2, wherein the rotation of the input shaft is shifted and transmitted to the output shaft,
An eccentric mechanism in which the amount of eccentricity from the axis of the input shaft connected to the rotation shaft of the drive source is variable, and an input side fulcrum that rotates together with the input shaft and the eccentric mechanism;
An output side fulcrum provided on the outer member of the one-way clutch;
A connecting rod having both ends connected to the input side fulcrum and the output side fulcrum and reciprocating in accordance with the amount of eccentricity of the eccentric mechanism;
The continuously variable transmission, wherein the inner member of the one-way clutch is coupled to the output shaft so as not to be relatively rotatable.

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