JP2005188662A - Fluid transmission gear with lock-up clutch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the occurrence of hysteresis to torque buffer property in a fluid transmission gear with a lock-up clutch provided with a plurality of arc springs between a driving member connected out of relative rotation to a clutch piston of the lock-up clutch, and a driven member connected out of relative rotation to a turbine impeller, and provided with a plurality of spring holding parts for holding the respective arc springs to either one of the driving member and the driven member. <P>SOLUTION: A clearance 61 for avoiding contact of the arc spring 47 with the spring holding part 48A even if the arc spring 47 is deformed, is formed between the arc spring 47 and a portion, facing the outer periphery of the arc spring 47, out of the spring holding part 48A so that the center part of the arc spring 47 along an imaginary circle C swells outward. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  According to the present invention, a plurality of arc springs are provided between a drive member coupled to a clutch piston of a lockup clutch so as not to rotate relative to a driven member coupled to a turbine impeller so as not to rotate relative thereto, and the drive member And a driven member is provided with a fluid transmission device with a lock-up clutch provided with a plurality of spring holding portions that hold the respective arc springs in a telescopic manner while facing at least the inner and outer circumferences of the plurality of arc springs. .

A torque converter with a lock-up clutch in which a driven member having a holding portion that covers a plurality of arc springs is fixed to a turbine impeller has already been known, for example, in Patent Document 1.
JP 2002-81522 A

  By the way, when connecting an input side rotary body and a turbine impeller by a lock-up clutch, each arc spring tends to be deformed so that its central portion is expanded outwardly by a compressive force acting on each arc spring. However, in the above-mentioned conventional one, the outer peripheral side of the arc spring comes into sliding contact with the spring holding portion, and sliding resistance is generated. As a result, hysteresis is generated in the torque buffering characteristic by the arc spring when the lockup clutch is directly connected and when the direct connection is released, which is not preferable.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a fluid transmission device with a lock-up clutch capable of suppressing the occurrence of hysteresis in torque buffering characteristics.

  In order to achieve the above object, the invention according to claim 1 is a lock-up clutch capable of directly connecting an input side rotating body coupled to a pump impeller and a turbine impeller opposed to the pump impeller. A drive piston coupled between the input-side rotator and the turbine impeller so as to be frictionally engageable with the input-side rotator, the drive member being coupled to the clutch piston so as not to be relatively rotatable, and the turbine impeller A plurality of arcs configured in an arc shape so that a center line is arranged on a virtual circle centering on the rotation axis of the turbine impeller in a natural state between the driven members coupled so as not to be relatively rotatable. A spring is provided, and one of the drive member and the driven member is opposed to at least an inner periphery and an outer periphery of the plurality of arc springs. In the fluid transmission device with a lock-up clutch provided with a plurality of spring holding portions that hold the respective arc springs so as to be extendable and contracted, between the portions of the spring holding portions facing the outer periphery of the arc springs and the arc springs Is formed with a gap for avoiding contact of each arc spring with each spring holding portion even if each arc spring is deformed so that a central portion of the arc spring along the virtual circle bulges outward. It is characterized by that.

  According to a second aspect of the present invention, in addition to the configuration of the first aspect of the present invention, a plurality of the spring holding portions are provided on the driven member.

  According to the first aspect of the present invention, the arc spring is compressed between the drive member and the driven member, so that contact with the spring holding portion is avoided even if the arc spring is deformed so as to bulge outward. There is no sliding resistance between the holding part and the arc spring. Therefore, it is possible to suppress the occurrence of hysteresis in the torque buffering characteristic by the arc spring during the direct connection operation of the lockup clutch and during the direct connection release operation.

  According to the invention described in claim 2, since the plurality of arc springs are held on the turbine impeller side, the clutch piston of the lockup clutch can be reduced in weight, and the operation responsiveness of the lockup clutch can be improved. Can do.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples of the present invention shown in the accompanying drawings.

  1 to 4 show a first embodiment of the present invention, FIG. 1 is a longitudinal side view of a torque converter with a lock-up clutch, and FIG. 2 is a view of FIG. 1 when the lock-up clutch is in a disconnected state. FIG. 3 is a cross-sectional view taken along line 2-2, FIG. 3 is a cross-sectional view corresponding to FIG. 2 when the lockup clutch is in a connected state, and FIG. 4 is a partially enlarged view of FIG.

  First, in FIG. 1, a torque converter TA which is a fluid transmission device includes a pump impeller 11, a turbine impeller 12 opposed to the impeller 11, and an inner peripheral portion of the pump impeller 11 and the turbine impeller 12. A stator impeller 13 is provided, and between these impellers 11, 12, and 13, a circulation circuit 14 for transmitting power by operating oil is formed.

  A front cover 15 as an input side rotating body that covers the turbine impeller 12 from the outside is joined to the pump impeller 11 by welding, and a starter motor (not shown) is attached to the outer peripheral surface of the front cover 15. The ring gear 16 to which the motive power is input is welded. On the other hand, the inner peripheral portion of the drive plate 18 facing the front cover 15 is fastened to the engine crankshaft 17 by a plurality of bolts 19... And the outer periphery of the drive plate 18 is connected to the ring gear by a plurality of bolts 20. 16 is fastened. That is, power from the crankshaft 17 is transmitted to the front cover 15.

  A boss 21 coaxial with the crankshaft 17 is welded to the inner peripheral portion of the turbine impeller 12, and a thrust needle bearing 22 is interposed between the boss 21 and the inner peripheral portion of the front cover 15. An output shaft 23 coaxial with the crankshaft 17 is splined to the boss 21. The output shaft 23 serves as a main shaft of a transmission (not shown).

  The output shaft 23 is coaxially surrounded by a stator shaft 24 that supports the hub 13 a of the stator impeller 13 via a free wheel 30, and a bearing bush 25 is interposed between the output shaft 23 and the stator shaft 24. The stator shaft 24 is non-rotatably supported by a fixed support portion 26 such as a transmission case. An auxiliary machine drive shaft 27 that coaxially surrounds the stator shaft 24 is coaxially fixed to the inner periphery of the pump impeller 11, and an oil pump (not shown) for supplying operating oil to the torque converter TA. Is driven by the accessory drive shaft 27.

  The free wheel 30 has an outer race 31 that is spline-fitted to the inner periphery of the hub 13 a of the stator impeller 13, an inner race 32 that is spline-fitted to the outer periphery of the stator shaft 24, and an annular shape between the races 31 and 32. It is a conventionally well-known thing which consists of several sprags 33 ... interposed by arrangement | sequence. Further, a thrust needle bearing 34 that regulates the axial movement of the free wheel 30 is provided between the free wheel 30 and the accessory drive shaft 27 coupled to the inner periphery of the pump impeller 11 and the hub 21 of the turbine impeller 12. , 35 are respectively interposed.

  The pump impeller 11 is integrally formed with a pump extension portion 11a that extends radially outward from the outer periphery thereof and is bent toward the turbine impeller 12 side. On the other hand, a cover extension 15a that extends radially outward from the turbine impeller 12 and is bent toward the pump impeller 11 is integrally formed on the outer periphery of the front cover 15, and this cover extension 15a. The ring gear 16 is welded, and the pump extension 11a is welded to the cover extension 15a.

  A clutch chamber 36 is defined around the turbine impeller 12, and the outer peripheral portion of the clutch chamber 36 communicates with the outer peripheral portion of the circulation circuit 14 between the pump impeller 11 and the turbine impeller 12.

  In the clutch chamber 36, a lock-up clutch 37A that can connect the front cover 15 and the turbine impeller 12 is disposed. The clutch piston 38 which forms the main body of the lock-up clutch 37A is provided in the clutch chamber 36 so as to partition the inside of the clutch chamber 36 into an inner chamber 36a on the turbine impeller 12 side and an outer chamber 36b on the front cover 15 side. The cylindrical boss 39 fixed to the inner peripheral portion of the clutch piston 38 is supported on the boss 21 of the turbine impeller 12 so as to be liquid-tight and axially slidable.

  A web 40 that extends outward in the radial direction of the turbine impeller 12 while being opposed to the inner surface of the cover extension 15 a of the front cover 15 is integrally formed on the outer periphery of the clutch piston 38. A cylindrical rim 41 facing the inner peripheral surface of the cover extension 15a is integrally connected. In addition, the web 40 is provided with a friction lining 42 that faces the inner surface of the cover extension 15a, and the clutch piston 38 is connected to the cover extension 15a of the front cover 15 in pressure contact. And a non-connection position (position in FIG. 1) that separates the friction lining 42 from the cover extension 15a.

  Referring also to FIG. 2, first and second drive members 43 and 44 are coupled to the clutch piston 38 so as not to be relatively rotatable, and a driven member 45 is coupled to the turbine impeller 12 so as not to be relatively rotatable. The center line is arranged between the first and second drive members 43 and 44 and the driven member 45 on a virtual circle C centering on the rotation axis of the turbine impeller 12 in a natural state. A plurality of pairs of arc springs 46... 47.

  In addition, in the first embodiment, a plurality of sets of the arc springs 46, 47,... Are connected to one of the first and second drive members 43, 44 and the driven member 45, in the first embodiment. A plurality of spring holding portions 48A are provided for holding the arc springs 46, 47,.

  The first drive member 43 on the turbine impeller 12 side and the second drive member 44 on the clutch piston 38 side are opposed to each other in the axial direction and fixed to the outer peripheral portion of the clutch piston 38, and are ring-shaped. Are attached to the clutch piston 38 with a plurality of rivets 49, 49... And radially outward from the mounting portions 43a, 44a with a space therebetween in the axial direction. Are integrally provided with ring-plate-like actuating plate portions 43b and 44b extending in the same direction.

  The operation plate portions 43b, 44b of the first and second drive members 43, 44 are provided with a plurality of arc-shaped openings 50, 51,. Each of the openings 50... 51 is formed by concentrically combining a pair of arc springs 46 having a small diameter and a relatively large arc spring 47 surrounding the arc spring 46. Inserted into….

  The first and second drive members 43, 44 include inner peripheral side flanges 43 c, 44 c that protrude from the sides of the inner peripheral edges of the openings 50, 51, and the openings 50,. The outer peripheral side flanges 43d and 44d are provided integrally with the outer peripheral edges of 51. Moreover, the inner peripheral side flanges 43c and 44c are bent in an arc shape so as to cooperate with the inner peripheral side accommodation groove 52 for accommodating the inner peripheral side of the arc springs 46 and 47, respectively, 43d and 44d are bent in an arc shape so as to cooperate with the outer peripheral side receiving groove 53 for receiving the outer peripheral side of the arc springs 46 and 47, and the spring holding portions 48A. It is comprised by the inner periphery side accommodation groove | channel 52 ... and outer periphery side accommodation groove | channel 53 ... which respond | corresponds to part 50 ..., 51 ... separately.

  The driven member 45 is formed in the shape of a ring plate so as to be accommodated between the operating plate portions 43b, 44b of the first and second drive members 43, 44 so as to be relatively rotatable. .., 47... Are accommodated in the driven member 45 so as to correspond to the openings 50... 51 of the first and second drive members 43, 44.

  The outer periphery of the driven member 45 protrudes from the outer periphery of the first and second drive members 43, 44, and engagement grooves 55 are provided at a plurality of locations spaced in the circumferential direction of the outer periphery of the driven member 45. . On the other hand, a connecting member 56 extending toward the outer peripheral side of the driven member 45 is welded to the outer periphery of the turbine impeller 12, and a plurality of engaging members 56 are engaged with the engaging grooves 55. The engaging protrusions 56a are integrally projected so as to extend in the axial direction.

  Therefore, the driven member 45 is coupled to the turbine impeller 12 such that relative movement in the axial direction is allowed but relative rotation is impossible.

  The openings 50, 51,... Of the first and second drive members 43, 44 and the openings 54,... Of the driven member 45 are in positions corresponding to each other when the torque converter TA is not operated. .., 47... Are in contact with both ends of the openings 50... 51.

  A first oil passage 58 is coaxially provided on the output shaft 23, and the first oil passage 58 communicates with the outer chamber 36 b of the clutch chamber 36 via the thrust needle bearing 22. An annular second oil passage 59 is formed between the auxiliary machine drive shaft 27 and the stator shaft 24, and the second oil passage 59 communicates with the inner peripheral portion of the circulation circuit 14 via the thrust needle bearing 34. To do. Moreover, the first and second oil passages 58 and 59 are connected to the discharge side of the oil pump, and are connected to an oil sump (not shown) for storing the working oil pumped up by the oil pump. Can be switched alternatively.

  In a state where the discharge side of the oil pump is connected to the first oil passage 58, the engine output torque is transmitted from the drive plate 18 to the pump impeller 11 via the front cover 15, thereby driving the oil pump. Then, the working oil flows from the first oil passage 58 through the thrust needle bearing 22 into the circulation circuit 14 through the outer chamber 36b and the inner chamber 36a of the clutch chamber 36, fills the circulation circuit 14, and then the second oil passage 59. Reflux to sump. At this time, in the clutch chamber 36, the outer chamber 36b has a higher pressure than the inner chamber 36a, the clutch piston 38 is pressed toward the side away from the front cover 15, and the lockup clutch 37A is disconnected. Yes. Therefore, when the pump impeller 11 is rotationally driven by the power transmission from the crankshaft 17, the working oil that fills the circulation circuit 14 circulates in the circulation circuit 14, so that the rotational torque of the pump impeller 11 is the turbine impeller. 12 and the output shaft 23 is driven.

  At this time, if a torque amplifying action is generated between the pump impeller 11 and the turbine impeller 12, the accompanying reaction force is borne by the stator impeller 13, and the stator impeller 13 is fixed by the locking action of the free wheel 30. Is done. When the torque amplifying operation is completed, the stator impeller 13 rotates in the same direction as the pump impeller 11 and the turbine impeller 12 while the free wheel 30 is idled by reversal of the torque direction received by the impeller 13. It will be.

  If the discharge side of the oil pump is connected to the second oil passage 59 when the torque converter TA is in the coupling state as described above, the working oil flows from the second oil passage 59 through the thrust needle bearing 34 to the circulation circuit. 14 flows into the circulation circuit 14 and then moves to the inner chamber 36a of the clutch chamber 36 to fill the inner chamber 36a. On the other hand, the outer chamber 36b of the clutch chamber 36 communicates with the oil sump via the thrust needle bearing 22 and the first oil passage 58, so that the inner chamber 36a has a higher pressure in the clutch chamber 36 than the outer chamber 36b. When the clutch piston 38 is pushed toward the front cover 15 and the friction lining 42 is pressed against the front cover 15, the lockup clutch 37A is brought into a connected state.

  When the lock-up clutch 37A is thus connected, the power transmitted from the crankshaft 17 to the front cover 15 via the drive plate 18 is transmitted to the pump impeller 11, and the clutch piston 38, the first and The turbine impeller 12 through one end of the openings 50... 51... Of the second drive members 43 and 44 through the arc springs 46. Will be transmitted mechanically. That is, the pump impeller 11 and the turbine impeller 12 are directly connected, and the output of the crankshaft 17 can be efficiently transmitted to the output shaft 23.

  At this time, if a sudden torque fluctuation occurs between the pump impeller 11 and the turbine impeller 12, the first and second drive members 43 and 44 respond to the rotation in the direction indicated by the arrow 60 as shown in FIG. The arc springs 46, 47,... Are compressed between one end of the openings 50, 51, and the other end of the openings 54, whereby the pump impeller 11 and the turbine impeller 12 rotate relative to each other to generate torque. The shock will be absorbed.

  By the way, when the front cover 15 and the turbine impeller 12 are connected by the lock-up clutch 37A, the arc springs 46, 47,. Attempts to deform so that it bulges to the side. When such deformation occurs, if the outer peripheral side of the arc spring 47... Of the arc spring 46. Hysteresis is produced in the torque buffering characteristics of the arc springs 46, 47, when the clutch 37A is directly connected and when the clutch 37A is released.

  Therefore, between the portion of the spring holding portion 48 </ b> A facing the outer periphery of the arc spring 47 and the arc spring 47, the arc spring 47 is formed so that the central portion of the arc spring 47 along the virtual circle C swells outward. A gap 61 is formed to avoid contact of the arc spring 47 with the spring holding portion 48A even if the arc spring 47 is deformed. In order to form such a gap 61, in this first embodiment, the outer peripheral edges of the openings 50 and 51 provided in the first and second drive members 43 and 44 have a smaller radius of curvature than the virtual circle C. Of the spring holding portions 48A, and provided in the first and second drive members 43 and 44 in such a manner that the outer peripheral side receiving grooves 53 for receiving the outer peripheral portion of the arc spring 47 are configured in cooperation. The gaps 61 are formed so that the outer peripheries of the arc springs 47 do not come into contact with the flanges 43d.

  Further, the opening 54 provided in the driven member 45 is formed so that the outer peripheral edge of the opening 54... 51 is not in contact with the outer peripheral edge of the arc spring 47. It is formed so as to be located radially outward from the outer peripheral edge.

  Thus, even if the arc springs 47 are deformed so as to bulge outward by being compressed between the first and second drive members 43 and 44 and the driven member 45, the spring holding portions 48A. Contact with the arc springs 47, so that there is no sliding resistance between the spring holding portions 48A and the arc springs 47, and when the lockup clutch 37A is directly connected and when the direct connection is released. It is possible to suppress the occurrence of hysteresis in the torque buffering characteristics by the arc springs 47 at the time of operation.

  FIG. 5 shows a second embodiment of the present invention, and parts corresponding to the first embodiment are given the same reference numerals.

  A lockup clutch 37B that can connect the front cover 15 and the turbine impeller 12 is disposed in the clutch chamber 36 of the torque converter TB, and a drive member 63 is disposed on the clutch piston 38 that forms the main body of the lockup clutch 37B. Are coupled so as not to be relatively rotatable while allowing relative movement in the axial direction, and the turbine impeller 12 is coupled to the first and second driven members 64 and 65 so as to be relatively unrotatable. Between the second driven members 64, 65, a plurality of pairs of arc springs 46, 47,.

  The drive member 63 is formed in a ring plate shape like the driven member 45 of the first embodiment, and the inner peripheral portion of the drive member 63 is connected to the support member 66 fixed to the clutch piston 38 with a shaft. Although directional relative movement is allowed, it is supported as non-rotatable.

  The first and second driven members 64 and 65 are disposed so as to sandwich the drive member 63 therebetween, and the first and second driven members are connected to the connecting member 67 fixed to the turbine impeller 12. The outer peripheral parts of 64 and 65 are fixed.

  By the way, in the drive member 63 and one of the first and second driven members 64, 65, in the second embodiment, a plurality of sets of the arc springs 46, 47 are provided on the first and second driven members 64, 65. Are provided with a plurality of spring holding portions 48B that hold the arc springs 46, 47, respectively, so as to be extendable while facing at least the inner circumference and the outer circumference, and the spring holding portions 48B, In the first embodiment, it is configured in the same manner as the spring holding portions 48A provided on the first and second drive members 43, 44.

  According to the second embodiment, the same effects as those of the first embodiment can be obtained, and the plurality of arc springs 46, 47,. The clutch piston 38 of 37B can be reduced in weight, and the operation responsiveness of the lockup clutch 37B can be improved.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. It is.

  For example, although the torque converters TA and TB have been described in the above embodiments, the present invention can also be implemented in connection with a fluid transmission device other than the torque converter, that is, a fluid joint that does not include a stator impeller.

It is a vertical side view of the torque converter with a lockup clutch of 1st Example. It is sectional drawing which follows the 2-2 line | wire of FIG. 1 when a lockup clutch is in a non-connection state. FIG. 3 is a cross-sectional view corresponding to FIG. 2 when the lockup clutch is in a connected state. FIG. 3 is a partially enlarged view of FIG. 2. It is a vertical side view of the torque converter with a lockup clutch of 2nd Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Pump impeller 12 ... Turbine impeller 15 ... Front cover 37A, 37B as an input side rotary body ... Lock-up clutch 38 ... Clutch piston 43, 44, 63 ... Drive Members 45, 64, 65 ... driven member 46 ... arc springs 48A, 48B ... spring holding portion 61 ... gap C ... virtual circle TA, TB ... torque converter which is a fluid transmission device

Claims (2)

  Lock-up clutches (37A, 37B) capable of directly connecting the input side rotor (15) coupled to the pump impeller (11) and the turbine impeller (12) opposed to the pump impeller (11) A clutch piston (38) disposed between the input-side rotor (15) and the turbine impeller (12) so as to be frictionally engageable with the input-side rotor (15), and the clutch piston (38) Between the drive member (43, 44; 63) coupled to the turbine impeller (12) and the driven member (45; 64, 65) coupled to the turbine impeller (12) so as not to rotate relative to each other. In the state, there are provided a plurality of arc springs (47) configured in an arc shape so as to arrange the center line on a virtual circle (C) centering on the rotation axis of the turbine impeller (12), One of the live member (43, 44; 63) and the driven member (45; 64, 65) is provided with each arc spring (at each of the arc springs (47)) facing at least the inner circumference and the outer circumference. 47) In the fluid transmission device with a lock-up clutch provided with a plurality of spring holding portions (48A, 48B) for holding each of the arc springs in a telescopic manner, each of the arc springs (47) of the spring holding portions (48A, 48B). Even if each arc spring (47) is deformed so that the central portion of the arc spring (47) along the virtual circle (C) swells outwardly between the portion facing the outer periphery and each arc spring (47). Gap (6 for avoiding contact of each arc spring (47) to each spring holding portion (48A, 48B) ) Lock-up clutch with hydraulic power transmission, wherein a is formed.   The fluid transmission apparatus with a lockup clutch according to claim 1, wherein a plurality of the spring holding portions (48B) are provided on the driven member (64, 65).

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