JP2011252584A - Lock-up device for torque converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lock-up device for a torque converter, certainly suppressing vibration caused by a coil spring.SOLUTION: This lock-up device 7 includes a plurality of large torsion springs 74, a plurality of medium torsion springs 75, and a plurality of small torsion springs 76. The free lengths of the plurality of small torsion springs 76 are respectively set to be shorter than any one of the large torsion springs 74 and medium torsion springs 75. The plurality of small torsion springs 76 are movably individually arranged on the inner periphery of any one of the large torsion springs 74 and medium torsion springs 75. The plurality of small torsion springs 76 are compressed in a rotational direction by relative rotation at a second torsional angle θ2 or more, larger than a first torsional angle θ1.

Description

  The present invention relates to a lockup device, and more particularly, to a lockup device for a torque converter for transmitting torque and absorbing / damping torsional vibration.

  In many cases, the torque converter is provided with a lock-up device for transmitting torque directly from the front cover to the turbine. This lock-up device is arranged in two rows on a piston that can be frictionally connected to the front cover, a retaining plate fixed to the piston, and a radially outer peripheral side and a radially inner peripheral side, and is supported by the retaining plate. A plurality of pairs of torsion springs and a driven plate elastically connected to the piston in the rotational direction via the plurality of torsion springs. The driven plate is fixed to the turbine (see Patent Document 1).

  Here, the piston divides the space between the front cover and the turbine in the axial direction, and when the friction facing that is annularly stretched around the outer periphery of the piston is pressed against the friction surface of the front cover, Torque is transmitted to the lockup device. Then, torque is transmitted from the lockup device to the turbine. At this time, torque fluctuations input from the engine are absorbed and attenuated by a plurality of torsion springs arranged on the outer inner periphery of the lockup device.

JP 2006-177418 A

  In the lockup device disclosed in Patent Document 1 (hereinafter referred to as a conventional lockup device), when a plurality of torsion springs are compressed, the torsional characteristics of the torsion springs are determined based on the torsional characteristics of the torsion springs. The In other words, in order to determine the torsional characteristics of a plurality of torsion springs, it is necessary to set the torsional characteristics of a pair of torsion springs.

  The torsion characteristic indicates the relationship between the torsion angle (rotation angle) of the torsion spring and the amount of torque fluctuation that can be attenuated by the torsion spring. For this reason, when the torsion spring is compressed, the torque fluctuation corresponding to the torsional rigidity of the torsion spring is attenuated.

  In the conventional lock-up device, the torsional characteristics are bilinear type (two-stage). Therefore, when the target attenuation of torque fluctuation increases, the initial vibration can be suppressed, but in order to secure the target attenuation, 2. It is necessary to increase the torsional rigidity. For this reason, the ratio of the second torsional rigidity to the first torsional rigidity is increased, and there is a possibility that new vibration due to the difference in rigidity occurs in the bending point of the torsional characteristics and in the range beyond the bending point. . That is, when the torsional characteristics are set to the bilinear type (two stages), there is a possibility that vibration due to the torsion spring may occur.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a lock-up device for a torque converter that can reliably suppress vibration caused by a coil spring.

  A lockup device for a torque converter according to a first aspect is a device for transmitting torque and absorbing / damping torsional vibration. The lockup device includes an input rotation member, an output rotation member, a plurality of first coil springs, a plurality of second coil springs, and a plurality of third coil springs.

  The plurality of first coil springs are compressed in the rotation direction by the relative rotation between the input rotation member and the output rotation member on the outer side in the radial direction. The plurality of second coil springs are compressed in the rotational direction by a relative rotation of the input rotation member and the output rotation member that is equal to or greater than the first relative angle inward in the radial direction. Each of the plurality of third coil springs is set to have a shorter free length than either one of the first coil spring and the second coil spring. The plurality of third coil springs are movably disposed on the inner peripheral portion of either one of the first coil spring and the second coil spring. The plurality of third coil springs are compressed in the rotational direction by relative rotation greater than or equal to a second relative angle greater than the first relative angle.

  In the present lock-up device, first, the plurality of first coil springs are compressed in the rotational direction by the relative rotation of the input rotating member and the output rotating member. Next, the plurality of second coil springs are compressed in the rotation direction by relative rotation of the input rotation member and the output rotation member that is equal to or greater than the first relative angle. Finally, the plurality of third coil springs are compressed in the rotational direction by relative rotation greater than or equal to the second relative angle greater than the first relative angle. As described above, by compressing at least one of the first coil spring, the second coil spring, and the third coil spring, a multi-stage torsion characteristic is formed.

  In the present invention, by setting the free length of the third coil spring to be shorter than the coil spring (either one of the first coil spring and the second coil spring) in which the third coil spring is disposed, That is, torsional characteristics of three or more steps are formed. As a result, even if the target amount of torque fluctuation increase, the first stage torsional rigidity can be set small. That is, the initial vibration due to the magnitude of the first stage torsional rigidity can be suppressed. In the present invention, the third coil spring is disposed on the inner peripheral portion of one of the first coil spring and the second coil spring. Thereby, a torsional characteristic of a plurality of stages can be formed without greatly changing the conventional configuration. That is, a space-saving and low-cost lockup device can be provided.

  In the lockup device for a torque converter according to a second aspect, in the device according to the first aspect, the third coil spring is set to have a shorter free length than the second coil spring. The third coil spring is movably disposed on the inner periphery of the second coil spring.

  In the present invention, the second coil spring is disposed radially inward, and the third coil spring is disposed on the inner peripheral portion of the second coil spring. In this way, by arranging the third coil spring in the second coil spring instead of the first coil spring, when the plurality of first coil springs are compressed in the rotational direction, that is, the lockup device is twisted in the first stage. When operating with characteristics, sliding hysteresis torque generated by centrifugal force can be reduced. In particular, when the lockup device operates with the torsional characteristics of the first stage, sound vibration performance is required, but vibration noise generated when the first coil spring is compressed can also be reduced.

  A torque converter lockup device according to a third aspect is the device according to the first or second aspect, wherein the plurality of first coil springs are composed of a plurality of pairs of coil springs. The two first coil springs of each pair are arranged in series. In this lockup device, first, each pair of first coil springs is compressed below the first relative angle. Next, above the first relative angle, each pair of the first coil springs and the plurality of second coil springs are compressed. Finally, above the second relative angle, each pair of first coil springs, each of the plurality of second coil springs, and each of the plurality of third coil springs are compressed.

  In this case, the multi-stage torsional characteristics are three-stage torsional characteristics composed of the first to third torsional rigidity. The first torsional rigidity is a rigidity when the two first coil springs of each pair are compressed. The second torsional rigidity is rigidity when each pair of the first coil springs and the plurality of second coil springs are compressed. The third torsional rigidity is rigidity when each pair of the first coil springs, the plurality of second coil springs, and the plurality of third coil springs are compressed. Thus, the three-stage torsional characteristics can be easily formed without greatly changing the conventional configuration. That is, a space-saving and low-cost lockup device can be provided.

  In particular, a lock-up device having a three-stage torsional characteristic reliably suppresses initial vibration caused by the magnitude of the first-stage torsional rigidity, compared to a lockup apparatus having a torsional characteristic of less than three stages. can do. Further, since the adjacent rigidity ratio, that is, the rigidity ratio between the Nth torsional rigidity and the (N + 1) th torsional rigidity (the rigidity ratio of the (N + 1) th torsional rigidity with respect to the Nth torsional rigidity; N is a natural number) can be reduced. The vibration that may occur when the bending point is exceeded, that is, the vibration due to the rigidity difference can be reliably suppressed.

  A torque converter lockup device according to a fourth aspect of the present invention is the device according to any one of the first to third aspects, wherein the plurality of first coil springs are composed of a plurality of pairs of coil springs. The two first coil springs of each pair are arranged in series. In this lock-up device, one of the first coil springs of each pair being compressed is in close contact with the line and the other one of the first coil springs of each pair being compressed is compressed below the first relative angle. The Next, above the first relative angle, the other first coil spring and the plurality of second coil springs of each pair are compressed. Finally, above the second relative angle, the other first coil spring of each pair, each of the plurality of second coil springs, and each of the plurality of third coil springs are compressed.

  In this case, the multi-stage torsion characteristic is a four-stage torsion characteristic constituted by the first to fourth torsional rigidity. The first torsional rigidity is a rigidity when the two first coil springs of each pair are compressed. The second torsional rigidity is the rigidity when one of the two first coil springs in each pair is in close contact with the line and the other of the two first coil springs in each pair is compressed. The third torsional rigidity is the rigidity when the other coil spring of each pair of the first coil springs and the plurality of second coil springs are compressed. The fourth torsional rigidity is a rigidity when the other coil spring of each pair of the first coil springs, the plurality of second coil springs, and the plurality of third coil springs are compressed. Thus, four-stage torsional characteristics can be easily formed without greatly changing the conventional configuration. That is, a space-saving and low-cost lockup device can be provided.

  In particular, a lock-up device having a four-stage torsional characteristic more reliably causes initial vibration due to the magnitude of the first stage torsional rigidity than a lock-up device having a torsional characteristic of less than four stages. Can be suppressed. In addition, since the rigidity ratio of the (N + 1) th torsional rigidity with respect to the Nth torsional rigidity can be made very small, vibration due to the difference in rigidity when the bending point of the torsional characteristics is exceeded can be more reliably suppressed.

  A lockup device for a torque converter according to a fifth aspect of the present invention is the device according to any one of the first to fourth aspects, further comprising a rotation restricting means for restricting the relative rotation between the input rotating member and the output rotating member. .

  In this case, relative rotation between the input rotating member and the output rotating member is restricted by the rotation restricting means. Then, the operation (damper operation) for absorbing and damping torsional vibrations by the first coil spring and the second coil spring stops. That is, the upper limit of the torsion characteristic is set by the rotation restricting means. In this way, by setting the upper limit of the torsion characteristic by the rotation restricting means, when the torsion angle becomes a predetermined magnitude or more, the torque can be reliably transmitted from the input rotating member to the output rotating member. it can.

  According to the present invention, in the lock-up device for a torque converter, the vibration caused by the coil spring can be reliably suppressed.

1 is a schematic vertical sectional view of a torque converter in which an embodiment of the present invention is employed. The top view which looked at the lockup device from the transmission side. The model figure which shows the three-stage torsional characteristic of the said lockup apparatus. The model figure at the time of the torsion spring action | operation of the said lockup apparatus. The model figure which shows the torsional characteristic of 4 steps | paragraphs of the said lockup apparatus (other embodiment). The model figure at the time of the torsion spring action of the lockup device (other embodiments).

[Basic configuration of torque converter]
FIG. 1 is a schematic longitudinal sectional view of a torque converter 1 (fluid torque transmitting device) in which an embodiment of the present invention is adopted. The torque converter 1 is a device for transmitting torque from a crankshaft of an engine to an input shaft of a transmission. An engine (not shown) is arranged on the left side of FIG. 1, and a transmission (not shown) is arranged on the right side of FIG. OO shown in FIG. 1 is a rotating shaft of the torque converter 1.

  The torque converter 1 includes a front cover 2, an impeller 4, a turbine 5, a stator 6, and a lockup device 7. A torus-shaped fluid working chamber 3 is formed by the impeller 4, the turbine 5, and the stator 6.

  The front cover 2 is a member to which torque is input via a flexible plate (not shown). The front cover 2 is a member disposed on the engine side, and includes an annular portion 21 and a cylindrical portion 22 that extends from the outer peripheral edge of the annular portion 21 toward the transmission side.

  A center boss 23 is provided at the inner peripheral end of the front cover 2. The center boss 23 is a cylindrical member extending in the axial direction, and is inserted into the center hole of the crankshaft.

  A flexible plate (not shown) is fixed to the engine side of the front cover 2 by a plurality of bolts (not shown). The flexible plate is a thin disk-shaped member that transmits torque and absorbs bending vibration transmitted from the crankshaft to the main body of the torque converter 1.

  Furthermore, the transmission side tip of the cylindrical portion 22 formed on the outer peripheral edge of the annular portion 21 is connected to the outer peripheral edge of the impeller shell 41 of the impeller 4 by welding. The front cover 2 and the impeller 4 form a fluid chamber filled with hydraulic oil.

  The impeller 4 mainly includes an impeller shell 41, an impeller blade 42 fixed inside the impeller shell 41, and an impeller hub 43 fixed on the inner peripheral portion of the impeller shell 41.

  The impeller shell 41 is disposed on the transmission side of the front cover 2 so as to face the front cover 2, and a fixing recess 41 a for fixing the impeller blade 42 is formed on the inner peripheral surface. The impeller blade 42 is a plate-like member and is a portion that is pressed by hydraulic oil. The impeller blades 42 are provided with convex portions 42 a that can be disposed in the fixed concave portions 41 a of the impeller shell 41 on the outer peripheral side and the inner peripheral side. An annular impeller core 44 is disposed on the turbine 5 side of the impeller blade 42. The impeller hub 43 is a cylindrical member that extends from the inner peripheral end of the impeller shell 41 to the transmission side.

  The turbine 5 is disposed so as to face the impeller 4 in the axial direction in the fluid chamber. The turbine 5 mainly includes a turbine shell 51, a plurality of turbine blades 52, and a turbine hub 53 fixed to the inner peripheral portion of the turbine shell 51. The turbine shell 51 is a substantially disk-shaped member. The turbine blade 52 is a plate-like member fixed to the surface of the turbine shell 51 on the impeller 4 side. A turbine core 54 is disposed on the impeller 4 side of the turbine blade 52 so as to face the impeller core 44.

  The turbine hub 53 is disposed on the inner peripheral portion of the turbine shell 51, and includes a cylindrical portion 53a extending in the axial direction and a disc portion 53b extending from the cylindrical portion 53a toward the outer periphery. The inner peripheral portion of the turbine shell 51 is fixed to the disc portion 53 b of the turbine hub 53 by a plurality of rivets 55. A spline that engages with the input shaft is formed on the inner peripheral portion of the cylindrical portion 53 a of the turbine hub 53. Thereby, the turbine hub 53 rotates integrally with the input shaft.

  The stator 6 is a mechanism for rectifying the flow of hydraulic oil that returns from the turbine 5 to the impeller 4. The stator 6 is a member that is integrally manufactured by forging with resin, aluminum alloy, or the like. The stator 6 mainly includes an annular stator carrier 61, a plurality of stator blades 62 provided on the outer peripheral surface of the stator carrier 61, and a stator core 63 provided on the outer peripheral side of the stator blade 62. The stator carrier 61 is supported by a cylindrical fixed shaft (not shown) via a one-way clutch 64.

  The impeller shell 41, the turbine shell 51, and the stator carrier 61 form a torus-shaped fluid working chamber 3 in the fluid chamber. An annular space is secured between the front cover 2 and the fluid working chamber 3 in the fluid chamber.

  A resin member 10 is disposed between the inner peripheral portion of the front cover 2 and the cylindrical portion 53a of the turbine hub 53, and a first port 11 capable of communicating hydraulic oil in the radial direction with the resin member 10. Is formed. The first port 11 communicates an oil passage provided in the input shaft and a space between the turbine 5 and the front cover 2. A first thrust bearing 12 is disposed between the turbine hub 53 and the inner peripheral portion of the stator 6. The first thrust bearing 12 has a second port 13 through which hydraulic fluid can communicate in the radial direction. Is formed. A second thrust bearing 14 is disposed between the stator 6 and the impeller 4 in the axial direction. The second thrust bearing 14 is formed with a third port 15 through which hydraulic oil can communicate in the radial direction. Yes. Each of the ports 11, 13, 15 can supply and discharge hydraulic oil independently.

[Structure of lock-up device]
The lockup device 7 is a device for transmitting torque from an engine crankshaft and absorbing and damping torsional vibrations. As shown in FIG. 1, the lockup device 7 is disposed in a space between the turbine 5 and the front cover 2 and is a mechanism for mechanically connecting the two as necessary. The lockup device 7 is disposed in a space A between the front cover 2 and the turbine 5 in the axial direction. The lock-up device 7 is arranged so as to divide the space A substantially in the axial direction. Here, a space between the front cover 2 and the lockup device 7 is a first hydraulic chamber B, and a space between the lockup device 7 and the turbine 5 is a second hydraulic chamber C.

  The lock-up device 7 has functions of a clutch and an elastic coupling mechanism, and mainly includes a piston 71, a retaining plate 72, a driven plate 73 as an output rotating member, and a plurality of large torsion springs 74 (first coil). Spring), a plurality of middle torsion springs 75 (second coil springs), a plurality of small torsion springs 76 (third coil springs), and a support member 77.

  Here, FIG. 2 is a plan view of the lockup device 7 as viewed from the transmission side. 2 is a partial cross-sectional view for explaining the positional relationship between the middle torsion spring 75 and the small torsion spring 76 (the middle torsion spring 75 and the small torsion spring 76 displayed above in FIG. 2). See).

  The piston 71 is a member for engaging / disengaging the clutch, and further functions as an input member in the lockup device 7 as an elastic coupling mechanism. The piston 71 is disposed so as to be rotatable with respect to the crankshaft of the engine. The piston 71 is a disk-shaped member having a circular hole formed in the center. The outer end 71g of the piston 71 extends to the outer peripheral edge of the retaining plate 72, that is, the outer peripheral edge of the outer peripheral projection 72c.

  The piston 71 extends in the radial direction inside the space A so as to divide the space A substantially in the axial direction. The piston 71 has a recess 71a that is curved toward the engine side at a substantially central portion in the radial direction. A part of the middle torsion spring 75 is disposed in the recess 71a.

  The piston 71 is formed with a recess 71b that is curved toward the transmission side on the outer periphery side of the recess 71a, and a flat portion 71c that is orthogonal to the axial direction on the outer periphery side of the recess 71b. A friction facing 71d is provided on the surface of the flat portion 71c on the engine side.

  Here, a flat portion 2 a is formed on the front cover 2, and the flat portion 2 a of the front cover 2 is a portion facing the friction facing 71 d of the piston 71. The clutch portion of the lockup device 7 is realized by the flat portion 2a of the front cover 2, the flat portion 71c of the piston, and the friction facing 71d of the piston 71.

  An inner peripheral cylindrical portion 71 e extending toward the axial engine side is formed on the inner peripheral edge of the piston 71. The inner peripheral cylindrical portion 71 e is supported on the outer peripheral surface of the turbine hub 53. The piston 71 is movable in the axial direction and can contact the front cover 2. Further, an annular seal ring 71 f that abuts on the inner peripheral surface of the inner peripheral cylindrical portion 71 e is provided on the outer peripheral portion of the turbine hub 53. The seal ring 71f seals the inner periphery of the piston 71 in the axial direction.

  As shown in FIG. 2, the retaining plate 72 is an annular member and is a metal member. The retaining plate 72 includes a fixing portion 72a, three support portions 72b, an outer peripheral protrusion 72c (radial support portion), a rotation restricting portion 72d, a spring storage portion 72e, and a circumferential support portion 72m. And have.

  The fixed portion 72a is a portion formed in a substantially annular shape, and is fixed to the recessed portion 71b of the piston 71 by a plurality of rivets 72f. The support portion 72 b is a portion that supports the circumferential end portion of the large torsion spring 74. Moreover, the support part 72b protrudes toward the outer peripheral side from the fixing | fixed part 72a, and is integrally formed in the fixing | fixed part 72a. Further, the support portions 72b are provided at predetermined intervals in the circumferential direction.

  The support portion 72b has plate-like circumferential support portions 72h (circumferential support portions 72h on the outer peripheral side) that extend toward the transmission side at both circumferential ends of the outer peripheral portion. The outer circumferential side support portion 72 h can contact the circumferential end portion of the large torsion spring 74. The outer peripheral protruding portion 72c is a portion that protrudes further to the outer peripheral side from the support portion 72b. The outer peripheral protrusion 72c is disposed between two large torsion springs 74 adjacent in the circumferential direction.

  The rotation restricting portion 72 d is a portion that restricts relative rotation between the retaining plate 72 and the driven plate 73 by contacting the driven plate 73. The rotation restricting portion 72d is formed in a plate shape so as to protrude from the outer peripheral edge of the fixed portion 72a toward the transmission side at the central portion between the support portions 72b adjacent in the circumferential direction. At both ends in the circumferential direction of the rotation restricting portion 72d, contact with the driven plate 73 is possible.

  The spring storage portion 72e is a portion that can store the middle torsion spring 75, and is provided so as to protrude from the fixed portion 72a toward the inner peripheral side. Further, the spring housing portion 72e has another circumferential support portion 72m (inner circumferential side circumferential support portion 72m) formed on the inner circumferential side of the outer circumferential side circumferential support portion 72h. The inner circumferential side support portion 72 m can contact the circumferential end portion of the middle torsion spring 75.

  The driven plate 73 is an annular member made of sheet metal. An inner peripheral portion of the driven plate 73 is fixed to the turbine hub 53 by a plurality of rivets 55. Further, the driven plate 73 has three window holes (not shown) in which the middle torsion springs 75 are arranged at a substantially central portion in the radial direction. A circumferential support portion 73b (circumferential support portion 73b on the outer peripheral side) that is bent toward the engine side is formed at the outer peripheral end portion of the driven plate 73. Further, a circumferential support portion 73f (inner peripheral side circumferential support portion 73f) curved toward the engine side is provided at the radial center portion of the driven plate 73, that is, on the inner peripheral side of the circumferential support portion 73b on the outer peripheral side. Is formed.

  The outer circumferential side support portion 73 b can come into contact with the circumferential end portion of the large torsion spring 74. The pair of two large torsion springs 74 are compressed between the circumferential support portion 73 b of the driven plate 73 and the circumferential support portion 72 h on the outer peripheral side of the retaining plate 72. The inner circumferential side circumferential support portion 73 f can come into contact with the circumferential end portion of the middle torsion spring 75. Each of the plurality of middle torsion springs 75 is compressed between the circumferential support portion 73 f of the driven plate 73 and the circumferential support portion 72 m on the inner peripheral side of the retaining plate 72.

  Further, the driven plate 73 is formed with an abutting portion 73c with which the rotation restricting portion 72d of the retaining plate 72 abuts. The rotation of the driven plate 73 is restricted by the contact portion 73 c coming into contact with the rotation restricting portion 72 d of the retaining plate 72. The rotation restricting portion 72d of the retaining plate 72 and the contact portion 73c of the driven plate 73 constitute a rotation restricting means.

  The large torsion spring 74 transmits power between the piston 71 and the driven plate 73 via the retaining plate 72. The large torsion spring 74 absorbs and attenuates torsional vibration. The large torsion spring 74 is disposed on the transmission side of the piston 71. In the present embodiment, three pairs (three sets) of large torsion springs 74 (six large torsion springs 74) are arranged side by side in the circumferential direction. The pair of large torsion springs 74 includes two large torsion springs 74. As shown in FIG. 2, spring seats 74 a are arranged at both circumferential ends of the large torsion spring 74. The spring seat 74a includes a disc-shaped portion (a portion indicated by 74a in FIG. 2) that supports the circumferential end of the large torsion spring 74, and an inward direction of the large torsion spring 74 from the disc-shaped portion. It has a protruding support part (not shown) that protrudes, and is supported by the retaining plate 72.

  The middle torsion spring 75 transmits power between the retaining plate 72 and the driven plate 73. Further, the middle torsion spring 75 absorbs and attenuates torsional vibration. The middle torsion spring 75 is disposed on the inner peripheral side of the large torsion spring 74. The middle torsion spring 75 is disposed on the transmission side of the piston 71. Here, three middle torsion springs 75 are arranged side by side in the circumferential direction. Each of the three middle torsion springs 75 is compressed in cooperation with the pair of large torsion springs 74, and the basic torsional characteristics of the lockup device 7 are formed by this compression.

  The small torsion spring 76 is disposed on the inner periphery of the middle torsion spring 75. The free length of the small torsion spring 76 is set to be shorter than the length of the middle torsion spring 75 disposed on the retaining plate 72. That is, in a state where the retaining plate 72 and the driven plate 73 are not rotating relative to each other, the small torsion spring 76 is movably disposed on the inner peripheral portion of the middle torsion spring 75. Then, when the retaining plate 72 and the driven plate 73 start relative rotation and rotate relative to a predetermined relative angle or more, which will be described later, the small torsion spring 76 is compressed together with the middle torsion spring 75. In this way, the small torsion spring 76, along with the middle torsion spring 75, absorbs and attenuates torsional vibration.

  The support member 77 is a member that supports the outer peripheral side of the large torsion spring 74. Further, the support member 77 includes an outer peripheral side support portion 77a, three projecting portions 77b, a movement restricting portion 77c, and an intermediate portion 77d (see FIG. 2).

  The outer peripheral side support portion 77a is a portion that supports the outer peripheral side of the large torsion spring 74, and is disposed on the outer peripheral side of the large torsion spring 74 as shown in FIG. Moreover, the outer peripheral side support part 77a is a cylindrical part extended along an axial direction. Further, the outer peripheral side support portion 77 a is supported in the radial direction by the tip of the outer peripheral side protruding portion 72 c of the retaining plate 72. The outer peripheral side support part 77a is disposed on the axial transmission side of the outer peripheral side protruding part 72c.

  The protruding portion 77b is provided at the engine side end of the outer peripheral side support portion 77a, and protrudes from the inner peripheral surface of the outer peripheral side support portion 77a to the inner peripheral side. The protrusions 77b are arranged at equal intervals in the circumferential direction. Further, the protruding portion 77 b is a portion disposed between the outer end 71 g of the piston 71 and the outer peripheral side protruding portion 72 c of the retaining plate 72 in the axial direction. When the support member 77 attempts to move toward the axial transmission side, the protrusion 77b comes into contact with the engine-side surface of the outer peripheral protrusion 72c, so that the movement of the support member 77 is restricted. Further, when the support member 77 tries to move to the axial direction engine side, the protrusion 77b comes into contact with the transmission side surface of the outer end 71g of the piston 71, so that the movement of the support member 77 to the engine side is restricted. This protrusion 77b is arranged corresponding to the outer peripheral protrusion 72c. That is, the large torsion spring 74 is provided at a position where it is not disposed in the circumferential direction.

  The movement restricting portion 77c is a portion for restricting the movement of the large torsion spring 74 to the transmission side and is a portion extending from the transmission side end portion of the outer peripheral side support portion 77a toward the inner peripheral side. The movement restricting portion 77c has a restricting portion 76e. The restricting portion 76e is a portion that restricts the movement of the large torsion spring 74 by contacting the large torsion spring 74 when the large torsion spring 74 is about to move to the transmission side. The restricting portion 76e is a portion extending from the transmission-side end portion of the outer peripheral side support portion 77a toward the inner peripheral side. It should be noted that the axial distance between the movement restricting portion 77 c and the piston 71 is larger than the diameter of the large torsion spring 74 in a state where the protruding portion 77 b is in contact with the retaining plate 72. That is, a gap is formed between the movement restricting portion 77 c and the large torsion spring 74.

  As shown in FIG. 2, the intermediate portion 76 d is a portion capable of supporting the circumferential end portion of the large torsion spring 74, and is disposed between the circumferential directions of the two large torsion springs 74 adjacent to each other. The intermediate portion 76d is a portion extending from the movement restricting portion 77c toward the engine side.

[Torque converter operation]
Immediately after the engine is started, the hydraulic oil is supplied into the main body of the torque converter 1 from the first port 11 and the third port 15, and the hydraulic oil is discharged from the second port 13. The hydraulic oil supplied from the first port 11 flows in the space between the piston 71 and the front cover 2 (first hydraulic chamber B) to the outer peripheral side, and the space between the piston 71 and the turbine 5 (second hydraulic chamber). C) to flow into the fluid working chamber 3.

  The hydraulic oil supplied from the third port 15 into the main body of the torque converter 1 moves toward the impeller 4 and is moved toward the turbine 5 by the impeller 4. Then, the hydraulic oil that has moved to the turbine 5 side is moved to the stator 6 side by the turbine 5 and supplied to the impeller 4 again. By this operation, the turbine 5 is rotated.

  The power transmitted to the turbine 5 is transmitted to the input shaft. In this way, power is transmitted between the crankshaft of the engine and the input shaft. At this time, the piston 71 is separated from the front cover 2, and the torque of the front cover 2 is not transmitted to the piston 71.

[Operation of lock-up device]
When the rotational speed of the torque converter 1 increases and the input shaft reaches a certain rotational speed, the hydraulic oil in the first hydraulic chamber B is discharged from the first port 11. As a result, due to the hydraulic pressure difference between the first hydraulic chamber B and the second hydraulic chamber C, the piston 71 is moved to the front cover 2 side, and the friction facing 71d is pressed against the flat friction surface of the front cover 2. When the friction facing 71 d is pressed against the front cover 2, the torque of the front cover 2 is transmitted from the piston 71 to the driven plate 73 via the retaining plate 72 and the large torsion spring 74. Further, the torque transmitted to the driven plate 73 is transmitted from the driven plate 73 to the turbine 5. That is, the front cover 2 is mechanically coupled to the turbine 5, and the torque of the front cover 2 is directly output to the input shaft via the turbine 5.

[Torsional characteristics of lock-up device]
In the lockup coupled state described above, the lockup device 7 transmits torque. The lockup device 7 absorbs and attenuates the torsional vibration input from the front cover 2 along with the torque transmission based on the torsional characteristics.

  Below, the twist characteristic of the lockup apparatus 7 is demonstrated using FIG. 3 and FIG. FIG. 3 is a model diagram showing the three-stage torsional characteristics of the lockup device 7, and FIG. 4 is a model diagram when the torsion spring is compressed in the lockup device 7. 3 and 4 are model views when a pair of large torsion springs 74, one intermediate torsion spring 75, and one intermediate torsion spring 75 are compressed.

  In FIG. 4, in order to distinguish a pair of large torsion springs 74, that is, two large torsion springs 74, the number of one large torsion spring 74 of the two large torsion springs 74 is denoted by 74 a, and the two large torsion springs 74 The number of the other large torsion spring 74 is denoted by 74b.

  Specifically, when a torsional vibration is input from the front cover 2 to the lockup device 7, a torsion angle θ is generated between the drive plate 72 and the driven plate 73. Then, as shown in FIG. 4A, the two large torsion springs 74 a and 74 b of each pair are compressed in the rotational direction between the retaining plate 72 and the driven plate 73. Specifically, the two large torsion springs 74 a and 74 b of each pair are compressed in the rotational direction between the circumferential support portion 72 h on the outer peripheral side of the retaining plate 72 and the circumferential support portion 73 b of the driven plate 73. . This state is referred to as a first compressed state J1 (see FIG. 3). In the first compressed state J1, the torsional characteristics of the first stage are defined by the torsional rigidity obtained by combining the torsional rigidity of the two large torsion springs 74a and 74b, that is, the first torsional rigidity D1. The torsional vibration is absorbed and damped based on the first stage torsional characteristics.

  When the torsion angle θ increases in this state, the compression of the middle torsion spring 75 is started in the state where the two large torsion springs 74a and 74b are compressed, as shown in FIG. 4B. This state corresponds to the first bending point P1 in FIG. The first torsion angle (first relative angle) in this state is denoted as θ1 in FIG. Here, the large torsion springs 74 a and 74 b are compressed in the rotational direction between the circumferential support portion 72 h on the outer peripheral side of the retaining plate 72 and the circumferential support portion 73 b of the driven plate 73 in the same manner as described above. Further, the middle torsion spring 75 is compressed in the rotational direction between a circumferential support portion 72 m on the inner peripheral side of the retaining plate 72 and a circumferential support portion 73 f on the inner peripheral side of the driven plate 73. The state in which the torsion springs 74a, 74b, and 75 are compressed in this way is referred to as a second compressed state J2 (see FIG. 3). In the second compressed state J2, the torsional rigidity of the two large torsion springs 74a and 74b and the torsional rigidity obtained by synthesizing the torsional rigidity of the middle torsion spring 75, that is, the second torsional rigidity D2, provides the second stage torsional characteristics. It is prescribed. The torsional vibration is absorbed and damped based on the second stage torsional characteristics.

  When the torsion angle θ further increases in this state, the compression of the small torsion spring 76 starts in the state where the two large torsion springs 74a and 74b and the middle torsion spring 75 are compressed, as shown in FIG. 4C. Is done. This state corresponds to the second bending point P2 in FIG. The second twist angle (second relative angle) in this state is denoted as θ2 in FIG. Here, the large torsion springs 74 a and 74 b are compressed in the rotational direction between the circumferential support portion 72 h on the outer peripheral side of the retaining plate 72 and the circumferential support portion 73 b of the driven plate 73 in the same manner as described above. Further, the intermediate torsion spring 75 and the small torsion spring 76 are rotated in the rotational direction between the inner circumferential side support portion 72 m of the retaining plate 72 and the inner circumferential side support portion 73 f of the driven plate 73. Compressed. The state in which the torsion springs 74a, 74b, 75, and 76 are thus compressed is referred to as a third compressed state J3 (see FIG. 3). In the third compression state J3, the torsional rigidity obtained by synthesizing the torsional rigidity of the two large torsion springs 74a and 74b, the torsional rigidity of the middle torsion spring 75, and the torsional rigidity of the small torsion spring 76, ie, the third torsional rigidity D3. Third stage torsional characteristics are defined. The torsional vibration is absorbed and damped based on this third stage torsional characteristic.

  If the torsion angle θ further increases in this state, the rotation restricting portion 72 d of the retaining plate 72 finally comes into contact with the contact portion 73 c of the driven plate 73. This state corresponds to the state of the limit point P3 in FIG. The third torsion angle in this state is denoted as θ3 in FIG. Then, the compression of the torsion springs 74a, 74b, 75, and 76 in operation stops. This state is called a compression stop state JF (see FIG. 3). That is, the damper operation of the torsion springs 74, 75, and 76 is stopped.

[Torsional characteristics of lock-up device]
As described above, the torsional rigidity when the torsion springs 74, 75, and 76 operate will be described below with reference to FIGS. In order to facilitate the description, the description will be given here using the torsional rigidity of each of the pair of large torsion springs 74, one middle torsion spring 75, and one small torsion spring 76. Each of the torsional rigidity of the two large torsion springs 74 is denoted by symbol K11 and symbol K12, the torsional rigidity of one middle torsion spring 75 is denoted by symbol K2, and the torsional rigidity of one small torsion spring 76 is denoted by symbol This is indicated by K3.

  As shown in FIGS. 3 and 4, in the first compression state J1, the torsional rigidity of the two large torsion springs 74 arranged in series is the first torsional rigidity D1 (= 1 / {(1 / K11 + 1 / K12 )}). In this torsional characteristic, the range of the first compressed state J1 is a range in which the twist angle is 0 degree or more and less than θ1 degree.

  Next, when the middle torsion spring 75 is further compressed in addition to the pair of large torsion springs 74, the first compressed state J1 is shifted to the second compressed state J2. Then, in the second compressed state J2, the torsional rigidity obtained by combining the torsional rigidity K11, K12 of the two large torsion springs 74 and the torsional rigidity K2 of the middle torsion spring 75 arranged in parallel is the second torsional rigidity. D2 (= 1 / {(1 / K11 + 1 / K12)} + K2). In this torsion characteristic, the range of the second compressed state J2 is a range in which the twist angle is not less than θ1 degrees and less than θ2 degrees.

  Subsequently, when the compression of the small torsion spring 76 is further started in a state where the pair of large torsion springs 74a and 74b and the middle torsion spring 75 are compressed, the second compression state J2 to the third compression state. Move to J3. Then, in the third compression state J3, the torsional rigidity K11 and K12 of the two large torsion springs 74, the torsional rigidity K2 of the middle torsion spring 75, and the torsional rigidity K3 of the small torsion spring 76 arranged in parallel are obtained. The combined torsional rigidity is set as the third torsional rigidity D3 (= 1 / {(1 / K11 + 1 / K12)} + K2 + K3). In this way, a three-stage torsional characteristic is set. In this torsion characteristic, the range of the third compressed state J3 is a range in which the twist angle is not less than θ2 degrees and less than θ3 degrees.

  Finally, when transitioning from the third compression state J3 to the compression stop state JF, the twist angle θ of the torsion characteristic reaches the maximum twist angle θ. The torque when the torsion angle θ reaches the maximum torsion angle θ is the maximum torque in the torsional characteristics. In this torsional characteristic, the range of the compression stop state JF is a range in which the torsion angle is θ3 or more.

  In this torsional characteristic, the rigidity ratio α between the Nth torsional rigidity and the (N + 1) th torsional rigidity (the ratio of the (N + 1) th torsional rigidity to the Nth torsional rigidity) is set to 1.5 or more and 3.0 or less. Here, an example in which the ratio α of the (N + 1) th torsional rigidity to the Nth torsional rigidity is set to 1.5 or more and 3.0 or less is shown. However, the above ratio of torsional rigidity α is set to 2.0. It is desirable to set it to 2.5 or less.

  Here, the first-stage torsional characteristics and the second-stage torsional characteristics are used as the torsional characteristics in the normal range. For this reason, in the above description, the ratio of the third torsional rigidity D3 to the second torsional rigidity D2 is set within a predetermined range, for example, 1.5 to 3.0 or 2.0 to 2.5. In the following, no particular setting is required, and only the ratio of the second torsional stiffness D2 to the first torsional stiffness D1 is set within a predetermined range.

[Advantageous effects of torsional vibration damping characteristics]
In the present lock-up device 7, by setting the free length of the small torsion spring 76 to be shorter than that of the middle torsion spring 75, a multi-stage torsion characteristic, that is, a three-stage torsion characteristic is formed. As a result, even if the target amount of torque fluctuation increase, the first stage torsional rigidity can be set small. That is, the initial vibration due to the magnitude of the first stage torsional rigidity can be suppressed. In the present invention, the small torsion spring 76 is disposed on the inner peripheral portion of the middle torsion spring 75. Thereby, a three-stage torsion characteristic can be formed without significantly changing the conventional configuration. That is, a space-saving and low-cost lockup device can be provided.

  Further, in the present lock-up device 7, the third torsional rigidity D <b> 3 is formed by the compression of the small torsion spring 76. That is, when the small torsion spring 76 is compressed, the third torsional rigidity D3 is high. In this state, torque from the engine can be transmitted to the driven plate 73 on the inner peripheral side (position close to the rotation axis) where the small torsion spring 76 is disposed. That is, in this case, since the radial distance between the circumferential support portion 73f on the inner peripheral side of the driven plate 73 and the rivet 55 is shortened, the torque is converted to the turbine 5 (the turbine hub 53, the turbine shell 51, etc.), that is, the torque. It can be reliably transmitted to the converter.

  Further, in the lockup device 7, in the normal range, the rigidity ratio α between the Nth torsional rigidity and the (N + 1) th torsional rigidity (the rigidity ratio of the (N + 1) th torsional rigidity to the Nth torsional rigidity) is 1.5 or more and 3.0. Since it is set as follows, vibration that may occur when the bending point of the torsional characteristic is exceeded, that is, vibration due to a rigidity difference can be suppressed. In particular, when the rigidity ratio α of the (N + 1) th torsional rigidity with respect to the Nth torsional rigidity is set to 2.0 or more and 2.5 or less, vibration due to a rigidity difference that may occur when the bending point of the torsion characteristic is exceeded. Can be reliably suppressed. Thus, in this lockup device 7, the vibration resulting from the change in rigidity of the torsion spring can be reliably suppressed.

  Further, in the lockup device 7, relative rotation between the retaining plate 72 and the driven plate 73 is performed by the rotation restricting means that is configured by the rotation restricting portion 72 d of the retaining plate 72 and the contact portion 73 c of the driven plate 73. Is regulated. Then, the operation (damper operation) for absorbing and attenuating torsional vibrations by the torsion springs 74, 75, and 76 is stopped. That is, the upper limit of the torsion characteristic is set by the rotation restricting means. Thus, by setting the upper limit of the torsional characteristics by the rotation restricting means, the torque can be reliably transmitted from the retaining plate 72 to the driven plate 73 when the torsional angle becomes equal to or larger than the predetermined angle θ3. it can.

[Other Embodiments]
(A) In the above-described embodiment, an example in which the lockup device 7 has a three-stage torsional characteristic is shown. However, in the present invention, the torsional characteristic can be set to four or more stages. For example, in the configuration shown in FIGS. 1 and 2, an example in which the torsional characteristics are set to four stages is shown below. In the example shown below, portions that are not specifically described have the same configuration as the first embodiment, and perform the same operation as the first embodiment. Further, in FIGS. 5 and 6 shown below, the same members and characteristics as those in FIGS. 3 and 4 are denoted by the same symbols.

  Specifically, when a torsional vibration is input from the front cover 2 to the lockup device 7, a torsion angle θ is generated between the drive plate 72 and the driven plate 73. Then, as shown in FIG. 6A, the two large torsion springs 74a and 74b of each pair are compressed in the rotational direction between the retaining plate 72 and the driven plate 73, as in the first embodiment. The This state is referred to as a first compressed state J1 (see FIG. 5). In the first compressed state J1, the torsional characteristics of the first stage are defined by the torsional rigidity obtained by combining the torsional rigidity of the two large torsion springs 74a and 74b, that is, the first torsional rigidity D1. The torsional vibration is absorbed and damped based on the first stage torsional characteristics.

  When the torsion angle θ increases in this state, one large torsion spring 74a comes into close contact with each other as shown in FIG. 6B. This state corresponds to the first bending point P1 in FIG. The first torsion angle (first relative angle) in this state is denoted as θ1 in FIG. Note that the torsion angle θ1 when the large torsion spring 74a comes into close contact with each other is smaller than the torsion angle θ2 when compression of the middle torsion spring 75 described later is started. Here, the other large torsion spring 74 b is compressed in the rotational direction between the retaining plate 72 and the driven plate 73. This state is referred to as a second compressed state J2 (see FIG. 3). In the second compression state J2, the second stage torsional characteristic is defined by the torsional rigidity of one large torsion spring 74b, that is, the second torsional rigidity D2. The torsional vibration is absorbed and damped based on the second stage torsional characteristics.

  When the torsion angle θ further increases in this state, as shown in FIG. 6C, the compression of the middle torsion spring 75 is started in the state where one large torsion spring 74b is compressed. This state corresponds to the second bending point P2 in FIG. The second twist angle (second relative angle) in this state is denoted as θ2 in FIG. Here, the large torsion spring 74 b and the middle torsion spring 75 are compressed in the rotational direction between the retaining plate 72 and the driven plate 73. The state in which the torsion springs 74b and 75 are compressed in this way is referred to as a third compressed state J3 (see FIG. 5). In the third compression state J3, the torsional rigidity of the third stage is defined by the torsional rigidity obtained by synthesizing the torsional rigidity of one large torsion spring 74b and the torsional rigidity of the middle torsion spring 75, that is, the third torsional rigidity D3. The The torsional vibration is absorbed and damped based on this third stage torsional characteristic.

  When the torsion angle θ further increases in this state, the compression of the small torsion spring 76 is started in the state where the one large torsion spring 74b and the middle torsion spring 75 are compressed. This state corresponds to the third bending point P3 in FIG. The third twist angle (third relative angle) in this state is denoted as θ3 in FIG. Here, the large torsion spring 74 b, the middle torsion spring 75 and the small torsion spring 76 are compressed between the retaining plate 72 and the driven plate 73 in the rotational direction. The state in which the torsion springs 74b, 75, and 76 are thus compressed is referred to as a fourth compressed state J4 (see FIG. 5). In the fourth compression state J4, the torsional rigidity obtained by synthesizing the torsional rigidity of one large torsion spring 74b, the torsional rigidity of the middle torsion spring 75, and the torsional rigidity of the small torsion spring 76, that is, the fourth torsional rigidity D4 is 4 The torsional characteristics of the step are defined. The torsional vibration is absorbed and damped based on this fourth stage torsional characteristic.

  If the torsion angle θ further increases in this state, the rotation restricting portion 72 d of the retaining plate 72 finally comes into contact with the contact portion 73 c of the driven plate 73. This state corresponds to the state of the limit point P4 in FIG. The fourth twist angle in this state is denoted as θ4 in FIG. Then, the compression of the torsion springs 74b, 75, and 76 in operation stops. This state is referred to as a compression stop state JF (see FIG. 5). That is, the damper operation of the torsion springs 74, 75, and 76 is stopped.

  As described above, the torsional rigidity when the torsion springs 74 and 75 operate is set similarly to the first embodiment. For example, in the first compression state J1, the torsional rigidity of the two large torsion springs 74 arranged in series is set as the first torsional rigidity D1 (= 1 / {(1 / K11 + 1 / K12)}). . Next, in the second compression state J2, the torsional rigidity of one large torsion spring 74b is set as the second torsional rigidity D2 (= K12).

  Subsequently, in the third compression state J3, the torsional rigidity obtained by combining the torsional rigidity K12 of one large torsion spring 74b and the torsional rigidity K2 of the middle torsion spring 75 is set as the third torsional rigidity D3 (= K12 + K2). Is done. Subsequently, in the fourth compression state J4, the torsional rigidity obtained by synthesizing the torsional rigidity K12 of one large torsion spring 74, the torsional rigidity K2 of the middle torsion spring 75, and the torsional rigidity K3 of the small torsion spring 76 is the fourth torsional spring. It is set as the rigidity D4 (= K12 + K2 + K3). In this way, four-stage torsional characteristics are set.

  Finally, when transitioning from the fourth compression state J4 to the compression stop state JF, the twist angle θ of the torsion characteristic reaches the maximum twist angle θ. The torque when the torsion angle θ reaches the maximum torsion angle θ is the maximum torque in the torsional characteristics.

  In this torsional characteristic, the rigidity ratio α between the Nth torsional rigidity and the (N + 1) th torsional rigidity (the ratio of the (N + 1) th torsional rigidity to the Nth torsional rigidity) is set to 1.5 or more and 3.0 or less. Here, an example in which the ratio α of the (N + 1) th torsional rigidity to the Nth torsional rigidity is set to 1.5 or more and 3.0 or less is shown. However, the above ratio of torsional rigidity α is set to 2.0. It is desirable to set it to 2.5 or less.

  Here, the first stage torsional characteristics, the second stage torsional characteristics, and the third stage torsional characteristics are used as the torsional characteristics in the normal range. For this reason, in the above, the ratio of the fourth torsional rigidity D4 to the third torsional rigidity D3 is set within a predetermined range, for example, 1.5 to 3.0 or 2.0 to 2.5. In the following, the ratio of the second torsional rigidity D2 to the first torsional rigidity D1 and the ratio of the third torsional rigidity D3 to the second torsional rigidity D2 are set within a predetermined range without particularly requiring setting. Yes.

Even if the torsional characteristics are set to four stages as described above, the same effect as that of the first embodiment can be obtained.
(B) In the above embodiment, an example in which the small torsion spring 76 is disposed inside the middle torsion spring 75 has been described. However, the torsion spring in which the small torsion spring 76 is disposed is not limited to the above embodiment. Anyway. For example, the small torsion springs 76 may be disposed on the inner periphery of one of the two large torsion springs 74 in each pair. Further, for example, the small torsion springs 76 may be disposed on the inner peripheral portion of at least one of the two large torsion springs 74 in each pair.

  INDUSTRIAL APPLICABILITY The present invention can be used for a torque converter lockup device for transmitting torque and absorbing / damping torsional vibration.

7 Lock-up device 71 Piston 72 Retaining plate 72d Rotation restricting portion 73 Driven plate 73c Abutting portion 74, 74a, 74b Large torsion spring 75 Medium torsion spring 76 Small torsion spring D1 1st torsional rigidity D2 2nd torsional rigidity D3 3rd Torsional rigidity D4 Fourth torsional rigidity α Ratio of N + 1th torsional rigidity to Nth torsional rigidity θ1, θ2, θ3, θ4 First to fourth torsional angles (first to fourth relative angles)

Claims (5)

A torque converter lockup device for transmitting torque and absorbing / damping torsional vibrations,
An input rotating member;
An output rotating member;
A plurality of first coil springs compressed in the rotational direction by relative rotation between the input rotating member and the output rotating member, radially outward;
A plurality of second coil springs that are compressed in the rotational direction by a relative rotation of the input rotation member and the output rotation member that is equal to or greater than a first relative angle inside in the radial direction;
A free length is set shorter than any one of the first coil spring and the second coil spring, and each of the first coil spring and the first coil spring is arranged separately to be movable at an inner peripheral portion of the one coil spring. A plurality of third coil springs that are compressed in the rotational direction by relative rotation greater than or equal to a second relative angle greater than the angle;
Torque converter lockup device comprising: The third coil spring is set to have a shorter free length than the second coil spring, and is movably disposed on an inner peripheral portion of the second coil spring.
The lockup device for a torque converter according to claim 1. The plurality of first coil springs are composed of a plurality of pairs of coil springs,
The two first coil springs of each pair are arranged in series;
Below the first relative angle, each pair of the first coil springs is compressed,
Above the first relative angle, each pair of the first coil springs and the plurality of second coil springs are compressed,
Above the second relative angle, each pair of the first coil springs, each of the plurality of second coil springs, and each of the plurality of third coil springs is compressed.
The torque converter lockup device according to claim 1 or 2. The plurality of first coil springs are composed of a plurality of pairs of coil springs,
The two first coil springs of each pair are arranged in series;
When the angle is less than the first relative angle, either one of the first coil springs of each pair during compression is in close contact with the line, and the other of the first coil springs of each pair during compression is compressed,
Above the first relative angle, each of the other pair of the first coil springs and the plurality of second coil springs are compressed,
Above the second relative angle, each of the pair of the first coil springs, the plurality of second coil springs, and the plurality of third coil springs are compressed.
The torque converter lockup device according to any one of claims 1 to 3. A rotation restricting means (mechanical stopper) for restricting relative rotation between the input rotating member and the output rotating member;
The torque converter lockup device according to any one of claims 1 to 4, further comprising:

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