JP2019211082A - Torsional damper with conditionally actuated friction device - Google Patents

Abstract

To provide a torsional damper provided with a conditionally actuated friction device to be able to ensure adequate oscillation filtering when the transmitted drive torque is weak.SOLUTION: A torsional damper (1) includes: a first element (11) and second elements (9, 10) which relatively rotationally move around an axis (X); a first elastic device; a conditionally actuated second elastic device which is actuated when a drive torque equal to or greater than a forward torque threshold is transmitted from an input element toward an output element; and a conditionally actuated friction device which is configured to directly or indirectly rubs the second element (11), and which includes a first friction ring (25) rotationally coupled to at least one actuating member (31) disposed between a contact region in a reverse direction of the first elements (9, 10) and second elastic members (14, 16).SELECTED DRAWING: Figure 1

Description

  The present invention relates to the field of motor vehicle transmissions, and in particular to the field of torsional dampers for mounting on motor vehicle transmissions.

  The torque generated by the internal combustion engine is not constant and has a non-periodicity caused by continuous explosion in the cylinder of the engine. Such non-periodicity generates vibrations that are transmitted to the gearbox, which can cause particularly unpleasant shocks, noise and noise pollution. Thus, in general, automobile transmissions are equipped with torsional dampers that can filter vibrations upstream of the gearbox, avoiding particularly unpleasant shocks, noise or noise pollution. Such a torsional damper is in particular a dual mass flywheel (DMF) or forms part of a clutch disc or torque limiter.

  The torsional damper includes an input element coupled to the upstream portion of the transmission mechanism and an output element coupled to the downstream portion of the transmission mechanism. The input element and the output element relatively rotate around the axis X. The torsional damper further includes an elastic member, such as a spring, configured to transmit torque between the input element and the output element. The elastic member can transmit a driving torque (forward direction) from the input element to the output element, and can transmit a resistance torque (reverse direction) from the output element to the input element. The torsional damper includes a friction device, also called a hysteresis device, which exerts a frictional resistance torque during the relative rotation of the input element and the output element, and thereby some of the energy stored in the elastic member. It can diverge by friction.

  In general, the amplitude of vibration is greater at the start of the heat engine and is smaller under normal operating conditions of the heat engine. Therefore, the prior art is a conditionally actuated type that exerts a frictional resistance torque only at some relative position of the input element to the output element so that a greater friction torque is exerted during the desired operating phase, especially at start-up. Friction devices are known. In particular, a conditionally actuated friction device that generates a friction torque only when a resistance torque is transmitted from an output element toward an input element is known. Such a torsional damper has been found to be particularly effective for filtering vibrations at the start of the heat engine when resistance torque is transmitted from the output element to the input element at the start of the heat engine. . This is the case, for example, when a torsional damper is arranged between a heat engine arranged upstream and an electric machine arranged downstream and the heat engine is started via the electric machine.

  In order to realize such a hysteresis device, the hysteresis device is in frictional contact with one of the input element and the output element, and when the resistance torque passes through the torsional damper, it is driven exclusively by the other of the input element and the output element. Including a friction ring.

  However, the present applicant is not completely satisfied with such a torsional damper in that sufficient vibration filtering cannot be guaranteed when the transmission torque is low, especially when the vehicle gearbox is in the neutral position. It is considered.

  The basic idea of the invention comprises a conditionally actuated friction device that operates when resistance torque is transmitted, while ensuring sufficient vibration filtering when the transmitted drive torque is weak, It consists of proposing torsional dampers.

According to one embodiment, the present invention provides a torsional damper for being disposed between an upstream portion and a downstream portion of an automobile transmission mechanism, the torsional damper comprising:
A first element and a second element that are relatively rotationally moved about an axis X, wherein one of the first and second elements is combined in the upstream portion of the transmission mechanism, First and second elements, the other of which is combined in the downstream portion of the transmission mechanism;
An elastic damper system configured to mitigate aperiodicity and transmit torque between the first element and the second element, the elastic damper system comprising:
-On the one hand, between the first contact area in the forward direction of the first element and the first contact area in the reverse direction, and on the other hand, the first contact area in the forward direction of the second element; When the drive torque is transmitted from the input element toward the output element, the first and second elements include at least one first elastic member disposed between the first contact region in the reverse direction. The first abutment region in the reverse direction of the first and second elements between the first abutment region in the forward direction of the element and when resistance torque is transmitted from the output element to the input element A first elastic device in which the first elastic member is compressed,
-On the one hand, between the second contact area in the forward direction of the first element and the second contact area in the reverse direction, and on the other hand, the second contact area in the forward direction of the second element; At least one second elastic member disposed between the second abutment region in the reverse direction and the second elastic member in the rest position of the torsional damper in the order of the first element. First and second only when a drive torque greater than a forward torque threshold is transmitted from the input element to the output element, separated by a circumferential gap j in the second abutment region in the direction. A conditionally actuated second elastic device, wherein the second elastic member is compressed between the second contact regions in the forward direction of the element;
At least one actuation configured to directly or indirectly rub the second element and disposed between the second abutment region in the opposite direction of the first element and the second elastic member A conditionally actuated friction device rotationally coupled to a member and including a first friction ring, wherein a second abutment region in the reverse direction of the first element is an actuating member for transmission of resistance torque When the second elastic member is compressed against the second abutting region in the opposite direction of the second element via the conditionally actuated friction device, the friction torque between the first and second elements A conditionally actuated friction device adapted to exert,
including.

  Such a torsional damper ensures that only the first elastic device filters vibrations when a drive torque below the forward torque threshold is transmitted from the input element to the output element. Furthermore, since the conditionally actuated friction device does not cooperate with the first elastic device, the friction device does not interfere with the operation of the first elastic device, thereby operating when the resistance torque is transmitted. Despite the presence of the conditionally actuated friction device, it can be guaranteed that the vibrations are sufficiently filtered even when the transmission torque is weak.

  According to other advantageous embodiments, such a torsional damper may have one or more of the following features.

  According to one embodiment, in the first elastic device, the first elastic member has a first contact region in the forward direction of the first and second elements for all driving torques greater than zero. Configured to be compressed between.

  According to one embodiment, the first elastic device is configured such that when the driving torque less than the forward torque threshold is transmitted from the input element to the output element, the first elastic member It is configured to be compressed between the first contact areas in the forward direction of the two elements.

  According to one embodiment, the conditionally actuated friction device is configured to be actuated exclusively upon transmission of resistance torque.

  According to one embodiment, the at least one second elastic member is a second contact region in a direction opposite to the second contact region in the forward direction of the second element at the rest position of the torsional damper. Pre-compressed between.

  According to one embodiment, the at least one second elastic member is in a rest position between a second abutment region in the forward direction and a second abutment region in the reverse direction of the second element. The second compression device, which is pre-compressed with a pre-compression value and is conditionally actuated, has a second contact region in the reverse direction of the first element via the actuating member for transmission of resistance torque. When the second elastic member is compressed against the second contact region in the opposite direction of the two elements, a return torque greater than the friction torque generated by the conditionally operated friction device is generated. The elastic device is made to exert. In other words, the at least one second elastic member has a second abutment region in the opposite direction of the second element through the actuating member, regardless of the resistance torque transmitted. As long as the second elastic member is compressed against the second contact region in the direction, the conditionally actuated second elastic device has a return torque greater than the friction torque generated by the conditionally actuated friction device. Pre-compressed with such a value. Accordingly, the one or more second elastic members do not continue to be compressed between the actuating member and the second element even when the driving torque is transmitted.

  According to one embodiment, at the rest position of the torsional damper, the first elastic device is not pre-compressed or pre-compressed with a pre-compression value of less than 5 Nm. Thereby, even when the torque passing through the torsional damper is weak, the performance of the torsional damper can be further enhanced.

  According to one embodiment, the rigidity of the first elastic device and the circumferential gap j between the second elastic member and the second abutting region in the forward direction of the first element are: The direction torque threshold is in the range of 10-60 Nm, in particular 20 Nm-60 Nm.

  According to one embodiment, the second elastic member is separated by a circumferential gap k in the second abutment region in the reverse direction of the second element at the rest position of the torsional damper, The elastic member is compressed between the second contact areas in the reverse direction of the first and second elements only when a resistance torque equal to or greater than the reverse torque threshold is transmitted from the output element to the input element. It has become so.

  According to one embodiment, the actuating member is separated from the second abutment region in the reverse direction of the second element by the same circumferential gap as the circumferential gap k.

  According to one embodiment, the rigidity of the first elastic member and the circumferential gap k between the second elastic member and the second contact region in the opposite direction of the second element are opposite to each other. The direction torque threshold is set in the range of 5 to 30 Nm.

  According to one embodiment, one of the first and second elements includes a cover and the other of the first and second elements includes two guide rings disposed on opposite sides of the cover, respectively. Yes.

  According to one embodiment, the at least one first elastic member and the at least one second elastic member are arranged with the same diameter.

  According to one embodiment, the stiffness K1 of the first elastic device is 3-12 Nm / °.

  According to one embodiment, the first elastic member includes two coaxial linear springs attached to each other inside.

  According to one embodiment, the stiffness K2 of the second elastic device is 6-25 Nm / °.

  According to one embodiment, the second elastic member includes two coaxial linear springs attached to each other inside.

  According to one embodiment, the cover includes one opening for each of the first and second elastic members, each opening having two circumferentially opposed ends, One of the first contact areas in the forward direction and one of the first contact areas in the reverse direction, or one of the second contact areas in the forward direction and the second contact area in the reverse direction, respectively. Form one.

  According to one embodiment, the guide ring includes one opening portion for each of the first and second elastic members, and each opening portion has two end portions facing each other in the circumferential direction. Respectively, one of the first contact areas in the forward direction and one of the first contact areas in the reverse direction, or one of the second contact areas in the forward direction and the second contact in the reverse direction. One of the contact areas is formed.

  According to one embodiment, the first elastic device includes a plurality of first elastic members distributed circumferentially about the axis X, each of the first elastic members, on the one hand being the first Between the first contact region in the forward direction of the element and the first contact region in the reverse direction, and on the other hand, the first contact region in the direction opposite to the first contact region in the forward direction of the second element It arrange | positions between contact | abutting area | regions.

  According to one embodiment, the conditionally actuated second elastic device includes a plurality of second elastic members distributed circumferentially about the axis X, each of the second elastic members being On the one hand, between the second contact area in the forward direction of the first element and the second contact area in the reverse direction, on the other hand, opposite to the second contact area in the forward direction of the second element. Each of the second elastic members is circumferentially disengaged from the respective forward second abutment region of the first element at the rest position of the torsional damper. It is separated by a gap j in the direction.

  According to one embodiment, the conditionally actuated friction device includes one actuating member for each of the second elastic members, each actuating member being in contact with one of the second elastic members and the first. Between the elements and the respective second contact areas in the opposite direction.

  According to one embodiment, the conditionally actuated friction device includes an actuating ring that supports an actuating member, the actuating ring having or without a circumferential clearance. And rotationally coupled.

  According to one embodiment, this actuating member or each actuating member is an actuating leg.

  According to one embodiment, the actuating ring and the first friction ring have an axial leg supported by one of the actuating ring and the first friction ring in a notch provided on the other. Are rotationally coupled to each other.

  According to one embodiment, the axial fingers are accommodated in the notches with a circumferential clearance.

According to one embodiment, the conditionally actuated friction device further comprises:
-A support ring fixed to the first element;
A second friction ring rotationally coupled to the first element, wherein the first friction ring is disposed axially between the support ring and the second friction ring; ,
-Abutting on the one hand on the guide ring and on the other side on the second friction ring, the second friction ring on the first friction ring and this first friction ring on the support ring, for example, A disc spring-like elastic ring;
including.

  According to one embodiment, the present invention also includes an upstream portion with a heat engine, a downstream portion with a generator, and the torsional damper, wherein the input element of the torsional damper is an upstream portion. And torsional damper output element is coupled to the downstream part.

  According to one embodiment, the forward torque threshold is greater than the friction torque of a conditionally actuated friction device.

  According to one embodiment, the reverse torque threshold is greater than the friction torque of a conditionally actuated friction device.

  The invention will be further understood from reading the following description of a plurality of specific embodiments of the invention made by way of example only and not by way of limitation with reference to the accompanying drawings, in which: And the advantages will become more apparent.

It is a disassembled perspective view which shows the torsional damper by one Embodiment. FIG. 2 is a front view of the torsional damper of FIG. 1, in which a cover and an operating ring are indicated by dotted lines with a watermark. FIG. 3 is a detailed view of region III of FIG. 2 with the cover and actuation ring shown in dotted lines with a watermark. FIG. 4 is a detailed view of region IV in FIG. FIG. 4 is a detailed view corresponding to FIG. 3 for a torsional damper according to a second embodiment, with the cover and the operating ring shown in dotted lines with a watermark. 4 is a graph of features showing torque transmitted in response to swinging between an input element and an output element of a torsional damper according to one embodiment. It is a graph of the characteristic which shows the torque transmitted according to rocking | fluctuation between the input element and output element of a torsional damper by another embodiment. It is a graph of the characteristic which shows the torque transmitted according to the rocking | fluctuation between the input element and output element of a torsional damper which are not based on this invention.

  In the following description and claims, the terms “outer” and “inner” and the directions “axial” and “radial” are used to denote the elements of the torsional damper according to the definitions given in the description. To do. For convenience, the “radial direction” is a direction that is orthogonal to the rotational axis X of the torsional damper that determines the “axial direction” and that is away from the axis, and that faces from the inside to the outside. The direction is orthogonal to the axis and orthogonal to the radial direction. The terms “outer” and “inner” are used to define the relative position of one element relative to the other with respect to the rotational axis X of the torsional damper, so that an element close to the axis has a radius It is called the inner side by facing the outer element arranged in the direction peripheral part.

  The torsional damper 1 is for being arranged in a transmission mechanism of an automobile. In one particular embodiment, the torsional damper is arranged between the heat engine arranged downstream and the generator arranged upstream, in particular ensuring the start of the heat engine.

  In the illustrated embodiment, the torsional damper 1 is coupled to a friction disk 2 of a torque limiter. Such a torque limiter is intended to limit the torque passing through the transmission mechanism of an automobile and protect facilities that are vulnerable to overload. In such applications, the friction disk 2 includes a friction lining 3 that rotates on a drive flywheel secured to a crankshaft of a heat engine using a resiliently loaded pressure plate (not shown). Pressed against a support disk (not shown) to be joined. The elastic load of the pressure plate is such that when the torque passing through the transmission mechanism is less than the starting threshold value of the torque limiter, the friction disk 2 and the drive flywheel are rotationally coupled, and when the torque passing through the transmission mechanism is equal to or greater than the starting threshold value, It is intended to allow relative rotation of the friction disk and the drive flyhole, thereby limiting the torque through the transmission mechanism. However, it should be noted that the present invention is not limited to such applications, and the torsional damper 1 can be used in other applications as well, such as dual mass flywheels or clutch disks.

  As shown in FIG. 1, the friction disk 2 includes an outer disk 4 to which the friction lining 3 is fixed on both sides using, for example, rivets 5, and a hub 6. The hub 6 includes an inner spline for cooperating with an engagement spline formed on a driven shaft (not shown). The torsional damper 1 includes an input element 7 that is rotationally coupled to the outer disk 4, an output element 8 that is rotationally coupled to the hub 6, and an elastic damper system that alleviates aperiodicity, the elastic damper system comprising: The driving torque is transmitted from the input element 7 to the output element 8 (forward direction), and the resistance torque is transmitted from the output element 8 to the input element 7 (reverse direction).

  In the illustrated embodiment, the input element 7 includes two guide rings 9, 10, and the output element 8 includes a cover 11 that is axially disposed between the two guide rings 9, 10. . However, in an alternative embodiment not shown, the structure is reversed, the input element 7 fixed to the outer disk 4 includes a cover, and the output element 8 is arranged axially on both sides of the cover so that the hub 6 The two guide rings are fixed to each other.

  In FIG. 1, one guide ring 10 is fixed to the outer disk 4 by a set of rivets 12, and the two guide rings 9, 10 are fixed to each other by a second set of rivets 13 forming a spacer. .

  Further, the cover 11 has an inner periphery, and a tooth row that engages with a tooth row provided on the outer surface of the hub 6 so as to rotationally couple the cover 11 and the hub 6 is provided on the inner periphery. .

  The elastic damper system includes elastic members 14, 15, 16, and 17. In the illustrated embodiment, the elastic members 14, 15, 16, 17 include a plurality of linear coil springs distributed about the same diameter about the axis X in the circumferential direction. In the variant embodiment shown, the elastic damper system comprises four elastic members 14, 15, 16, 17 each composed of two coil springs arranged coaxially inside each other.

  The cover 11 and the guide rings 9, 10 include openings 18, 19, 20, respectively, each accommodating one of the elastic members 14, 15, 16, 17. The ends of the openings that oppose each other in the circumferential direction include radial regions that form contact regions for contacting the ends of the elastic members 14, 15, 16, and 17.

  In the illustrated embodiment, each end of the elastic member is provided with a support cap 21 to ensure that the stress exerted on the ends of the elastic members 14, 15, 16, 17 is properly distributed. Each of the support caps 21 is disposed to face three contact areas, that is, the contact area of the cover 11 and the contact areas of the two guide rings 9 and 10.

  In operation, when the engine torque is transmitted in the forward direction, that is, from the guide rings 9, 10 to the cover 11 via the elastic members 14, 15, 16, 17, the guide rings 9, 10 are indicated by an arrow f1 in FIG. It rotates relative to the cover 11 according to the first rotation direction. Therefore, each of the elastic members 14, 15, 16, and 17 is in contact with the two forward contact areas of the guide rings 9 and 10 at the first end, and the forward direction of the cover 11 at the second end. It abuts on the abutting area. On the other hand, when the engine torque is transmitted in the opposite direction, that is, from the cover 11 toward the guide rings 9 and 10, the guide rings 9 and 10 move relative to the cover 11 according to the second rotation direction indicated by the arrow f2 in FIG. Rotate. Therefore, each of the elastic members 14, 15, 16, and 17 contacts the reverse contact area of the cover 11 at the first end, and the reverse report of the guide rings 9 and 10 at the second end. It contacts two contact areas. Therefore, the elastic member transmits a driving torque (forward direction) from the guide rings 9 and 10 to the cover 11 and transmits a resistance torque (reverse direction) from the cover 11 to the guide rings 9 and 10. Can do.

  The elastic members 14, 15, 16, and 17 are distributed into two groups, the elastic members 15 and 17 belong to the first elastic device, and the elastic members 14 and 16 belong to the conditionally actuated second elastic device. .

  The elastic members 15 and 17 of the first elastic device shown in detail in FIG. 4 operate regardless of the swing angle of the guide rings 9 and 10 with respect to the cover 11. For this reason, the elastic members 15 and 17 of the first elastic device are arranged in the circumferential direction without a gap between the cover 11 and the guide rings 9 and 10. In other words, at the rest position of the torsional damper 1, the end portions of the elastic members 15 and 17 are simultaneously in contact with the contact area of the cover 11 and the two contact areas of the guide rings 9 and 10.

  Advantageously, the stiffness generated by the first elastic device is 3-12 Nm / °. Furthermore, in order not to impair the quality of the low torque filtering of the first elastic device, if the elastic members 15, 17 of the first elastic device are pre-compressed at the rest position of the torsional damper, this pre-compression The value of is small. Thus, advantageously, the first elastic device is pre-compressed with a pre-compression value of less than 5 Nm.

  Further, the elastic members 14 and 16 of the conditionally actuated second elastic device shown in FIG. 3 operate only with the threshold angle α of the forward swing of the guide rings 9 and 10 with respect to the cover 11 as a starting point. Therefore, at the rest position of the torsional damper 1, the two end portions of the elastic members 14 and 16 of the conditionally actuated second elastic device are in contact with the two forward directions of the guide rings 9 and 10. Abutting against the two abutting regions in the region or in opposite directions, and between each elastic member 14, 16 between the abutting region 22 in the forward direction of the cover 11 and the end facing the elastic member 14, 16 There is a circumferential gap j.

  In the variant embodiment illustrated in FIG. 5, the conditionally actuated second elastic device starts from the threshold angle α of the forward swing of the guide rings 9, 10 relative to the cover 11 and guides to the cover 11. It operates only with the threshold angle β of the reverse swing of the rings 9 and 10 as the starting point. Therefore, at the rest position of the torsional damper 1, the two end portions of the elastic members 14 and 16 of the conditionally actuated second elastic device are in contact with the two forward directions of the guide rings 9 and 10. It abuts on two abutting regions in the region or in opposite directions. Furthermore, in the said rest position, with respect to each elastic member 14, 16, there is a circumferential gap j between the forward contact area 22 of the cover 11 and the end facing the elastic member 14, 16. Further, a circumferential gap k exists between the contact region 23 in the reverse direction of the cover 11 and the end portion facing the elastic members 14 and 16.

  Advantageously, the stiffness generated by the conditionally actuated second elastic device is between 6 and 25 Nm / °.

  Further, the circumferential gap j between the elastic members 14, 16 and the forward contact region 22 of the cover is determined according to the rigidity of the first elastic device, and is a conditionally actuated second elasticity. The forward torque threshold with which the device is interposed is set in the range of 10 to 60 Nm.

  The circumferential gap k between the elastic members 14, 16 and the contact area 23 in the reverse direction of the cover is determined according to the rigidity of the first elastic device, and is a conditionally actuated second elasticity. The reverse torque threshold with which the device is interposed is set in the range of 5 to 30 Nm.

  Advantageously, according to one embodiment, the elastic members 14, 16 of the conditionally actuated second elastic device are precompressed circumferentially inside the openings 18, 19 of the guide rings 9, 10. The

  Referring again to FIG. 1, a conditionally actuated system in which the elastic damper system aims to radiate a portion of the energy stored in the elastic members 15, 15, 16, 17 in several operating stages by friction. It can be seen that it includes a friction device as well.

  The conditionally actuated friction device includes an actuating ring 24 and first and second friction rings 25, 26 that are rotationally coupled to the actuating ring 24 and one of the guide rings 9, respectively.

  For this reason, the actuating ring 24 includes an axial finger 27 received in a notch 28 provided in the first friction ring 25, and is configured to rotationally couple the actuating ring 24 and the first friction ring 25. Yes. Further, the second friction ring 26 includes an axial finger 29 accommodated in a notch 30 provided in the guide ring 9 so as to rotationally couple both of them.

  The actuating ring 24 further includes two actuating legs 31, i.e. one actuating leg for each elastic member 14, 16 of the conditionally actuated second elastic device. As shown in FIGS. 3 to 5, each of the actuating legs 31 has one end of the elastic members 14 and 16 of the conditionally actuated second elastic device and the opposite direction facing the cover 11. It is inserted between the contact area 23.

  Therefore, the actuating ring 24 is provided with each elastic member 14 during the relative movement of the guide rings 9 and 10 in the reverse direction (arrow f2) with respect to the cover 11, in particular for transmission of the resistance torque of the cover 11 to the guide ring. , 16 with respect to the guide rings 9, 10 so that the conditionally actuated friction device is activated only when it is compressed by the individual counter contact areas 23 via one actuating leg 31. Moving.

  According to one variant embodiment, the axial finger 27 of the actuating ring 24 is accommodated in the notch 28 of the first friction ring 25 with a circumferential clearance and the actuating ring 24 with respect to the first friction ring 25 is accommodated. Only with the swing threshold angle as a starting point, the first friction ring 25 is driven to rotate with respect to the guide rings 9 and 10, and the conditionally operated friction device is operated. The swing threshold angle is about 3 °, for example. Thereby, in the modified embodiment of FIG. 3, the conditionally operated friction device can be operated only when the resistance torque transmitted from the cover 11 to the guide rings 9 and 10 exceeds a threshold value.

  Furthermore, in the modified embodiment shown in FIG. 5, the same circumferential gap as the circumferential gap k is present between each actuating leg 31 and each contact area 23 in the opposite direction. The conditionally actuated friction device is activated in the reverse direction only when the second actuated elastic device is activated, i.e., when a resistance torque greater than the reverse torque threshold is transmitted. .

  The operating ring 24 is attached to the cover 11 with a gap in the axial direction so that the rotation of the cover 11 does not rotationally drive the operating ring 24 by friction.

  The conditionally actuated friction device further includes a support ring 32 fixed to the guide ring 9 using, for example, a rivet, and an elastic ring 33. The first and second friction rings 25 and 26 and the elastic ring 33 are sandwiched between the guide ring 9 and the support ring 32. In the illustrated embodiment, the elastic ring 33 abuts on the one hand on the guide ring 9 and on the other side abuts on the second friction ring 26 and abuts the second friction ring 26 on the first friction ring 25. Thus, the first friction ring is brought into contact with the support ring 32. Thus, when the first friction ring 25 is driven to rotate relative to the guide ring 2 by the actuating ring 24, it is on the one hand between the first friction ring 25 and the second friction ring 26 and on the other hand the first friction ring 25. Friction is exerted between the friction ring 25 and the support ring 32.

  The elastic ring 33 is generally a disc spring-shaped ring. The first and second friction rings 25, 26 are formed, for example, from an optionally fiber reinforced plastic material.

  Next, the operation of the torsional damper 1 will be described.

  When the torsional damper 1 is urged by driving torque, that is, torque transmitted from the guide rings 9 and 10 toward the cover 11, the guide rings 9 and 10 are moved relative to the cover 11 by the arrow f1 in FIGS. Rotation of the angle φ is performed in the forward rotation direction indicated by. As long as this angle φ is less than the swing threshold angle α, only the elastic members 15 and 17 of the first elastic device operate.

  When the angle φ is greater than or equal to the swing threshold angle α, the conditionally actuated second elastic device is activated. In fact, when the circumferential gap j is corrected, the cover 11 comes into contact with the elastic members 14 and 16 of the conditionally actuated second elastic device, compresses them, and these elastic members become the first. The elastic members 15 and 17 of the elastic device are operated in parallel. The conditionally actuated friction device is not used when the drive torque passes through the torsional damper 1.

  When the torsional damper 1 is urged by resistance torque, that is, torque transmitted from the cover 11 toward the guide rings 9, 10, the guide rings 9, 10 are moved toward the cover 11 with arrows in FIGS. 2 to 5. The angle φ is rotated in the reverse rotation direction indicated by f2.

  In the variant embodiment of FIG. 3, when the resistance torque passes through the torsional damper 1, the first elastic device and the conditionally actuated second elastic device are activated. Furthermore, the conditionally actuated friction device is operated in the same manner, and the first friction ring 25 is driven to rotate relative to the guide rings 9 and 10 via the axial fingers 27 of the actuation ring 24. Thus, the first friction ring 25 rubs the second friction ring 26 on the one hand and the support ring 32 on the other hand. Therefore, in the conditionally operated friction device, when the resistance torque passes through the torsional damper 1, the elastic members 14, 15, 16, and 17 of the first elastic device and the conditionally operated second elastic device are included. The energy stored in can be dissipated by friction.

  In the modified embodiment shown in FIG. 5, the conditionally actuated second elastic device and the conditionally actuated friction device correct the circumferential gap k, and the angle φ is greater than or equal to the swing threshold angle β. Operates only when

  FIG. 8 shows the torque C passing through the torsional damper in response to the relative oscillation about the axis X of the input element with respect to the output element of the torsional damper for a torsional damper not representative of the present invention. It is a graph. The torsional damper does not include a conditionally actuated second elastic device, and is a conditionally actuated friction device that is actuated when resistance torque is transmitted from the output element toward the input element However, the torsional damper is different from the torsional damper in that it does not include an operating leg portion inserted between the contact region in the reverse direction of the cover and the elastic member of the first elastic device.

  In the case of relative swinging in the reverse direction (lower left frame), the conditionally actuated friction device is actuated and the graph depends on whether the relative swinging angle in the reverse direction increases or decreases Do not follow the same route. The fact that there are two different paths indicates the energy divergence during the forward trip (from the rest angle position to the end of the stroke) and the return path (from the end of the stroke position to the rest angle position) Energy dissipation is caused by a conditionally actuated friction device.

  This graph shows the low torque of the torsional damper that does not have the feature of the present invention in particular that the conditionally actuated friction device is not coupled to the elastic member that is operated only with the forward swing threshold angle α as a starting point. Can show inconveniences in the area.

  In fact, in such a torsional damper 1, the friction system generates a friction resistance torque that is greater than the return torque generated by the elastic member in an attempt to return the torsional damper 1 to its rest position. In this case, in the return path to the rest position, the elastic member remains compressed between the operating leg portion of the operating ring and the contact area (FIG. 8, area A) of the guide ring.

  Thereafter, when the driving torque passes through the torsional damper 1, the elastic member is compressed between the cover 11 and the operating leg of the operating ring 24 until the driving torque exceeds the friction torque generated by the friction device. Therefore, a peak that impairs filtering for low torque near 0 Nm in the forward direction is observed (FIG. 8, region B). Thus, such a torsional damper cannot guarantee sufficient vibration filtering when the transmitted torque is zero or weak, for example when the vehicle gearbox is in the neutral position.

  FIG. 7 is a graph showing the torque C transmitted through the torsional damper 1 according to the modified embodiment of FIG. 5 according to the relative swinging of the guide rings 9 and 10 with respect to the cover 11. In such an embodiment, the conditionally actuated friction system is likewise provided by the return generated by the elastic members 4, 16 of the conditionally actuated second elastic device in an attempt to return the torsional damper 1 to the rest position. A friction resistance torque larger than the torque can be generated. Therefore, the elastic members 14 and 16 of the conditionally actuated second elastic device can similarly remain in a compressed state between the cover 11 and the actuating leg 31 of the actuating ring 24. However, in the torsional damper 1 described in connection with FIG. 4, only the first elastic device is activated when a driving torque less than the forward angle fluctuation threshold passes through the torsional damper 1. Therefore, the lock of the elastic members 14 and 16 of the conditionally actuated second elastic device in the compressed state does not affect the vibration filtering in this low torque region.

  Next, when the relative swing reaches the forward swing threshold angle α, the elastic members 14 and 16 of the conditionally actuated second elastic device transmit the drive torque transmitted to the conditionally actuated type. Until the friction torque generated by the friction device can be exceeded, compression is continued between the cover 11 and the operating leg 31 of the operating ring 24. Therefore, a peak is observed similarly (FIG. 6, area P). However, in this case, since the peak has shifted to a larger driving torque value side, this peak does not impair vibration filtering when the automobile gearbox is in the neutral position.

  FIG. 6 shows the torque C transmitted via the torsional damper 1 according to another variant embodiment of FIG. 5 in response to the relative swinging of the guide rings 9, 10 with respect to the cover 11. According to this variant embodiment, the elastic members 14, 16 of the conditionally actuated second elastic device are pre-compressed in the circumferential direction inside the openings 18, 19 of the guide rings 9, 10, so that the elastic member 14 , 16 is greater than the friction torque that can be generated by the conditionally actuated friction device. Therefore, the second elastic device always exerts a return torque that is greater than the friction torque generated by the conditionally actuated friction device. Therefore, no peak is observed in the graph of FIG.

  Although the invention has been described in connection with a number of specific embodiments, the invention is not limited thereto in any way, and any technical equivalents of the means described, as well as combinations thereof, are within the scope of the invention Needless to say.

  The use of the verbs “compeater”, “complement” or “include” and their conjugations does not exclude the presence of elements or steps other than those stated in the claims. .

  In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

Referring again to FIG. 1, a conditionally actuated system in which an elastic damper system is aimed at radiating some of the energy stored in the elastic members 14 , 15, 16, 17 by friction in several stages of operation. It can be seen that it includes a friction device as well.

Next, when the relative swing reaches the forward swing threshold angle α, the elastic members 14 and 16 of the conditionally actuated second elastic device transmit the drive torque transmitted to the conditionally actuated type. Until the friction torque generated by the friction device can be exceeded, the compression continues between the cover 11 and the operating leg 31 of the operating ring 24. Therefore, a peak is similarly observed (FIG. 7 , region P). However, in this case, since the peak has shifted to a larger driving torque value side, this peak does not impair vibration filtering when the automobile gearbox is in the neutral position.

Claims (11)

A torsional damper (1) for disposition between an upstream part and a downstream part of a transmission mechanism for an automobile, wherein the torsional damper (1) comprises:
A first element (11) and a second element (9, 10) which are relatively rotationally moved about an axis X, one of said first and second elements (9, 10; 11) Is an input element for coupling to the upstream part of the transmission mechanism, and the other of the first and second elements (11; 9, 10) is an output element for coupling to the downstream part of the transmission mechanism First and second elements,
An elastic damper system configured to alleviate non-periodicity and to transmit torque between the first element (11) and the second element (9, 10); Is
-On the one hand, between the first contact area in the forward direction of the first element (11) and the first contact area in the reverse direction, on the other hand, of the second element (9, 10); It includes at least one first elastic member (15, 17) disposed between the first contact region in the forward direction and the first contact region in the reverse direction, and the drive torque is output from the input element. When transmitted toward the element, between the first abutment region in the forward direction of the first and second elements, and when resistance torque is transmitted from the output element to the input element; A first elastic device in which the first elastic member (15, 17) is compressed between a first contact region in the opposite direction of the first and second elements;
-On the one hand, between the second contact area in the forward direction of the first element (11) and the second contact area in the reverse direction, on the other hand, of the second element (9, 10); Including at least one second elastic member (14, 16) disposed between the forward second abutment region (22) and the reverse second abutment region (23), The second elastic member (14, 16) is a circumferential clearance of the second contact region (22) in the forward direction of the first element (11) at the rest position of the torsional damper (1). j, so that a driving torque greater than or equal to the forward torque threshold is transmitted from the input element to the output element, the second contact region in the forward direction of the first and second elements. A conditionally actuated second elastic device, wherein the second elastic member (14, 16) is compressed between
A second abutment region (23) in the opposite direction of the first element (11) and the second elasticity, configured to rub against the second element (11) directly or indirectly A conditionally actuated friction device comprising a first friction ring (25) rotationally coupled to at least one actuating member (31) disposed between the members (14, 16), comprising a resistance torque For the transmission of the second element (9, 10), the second contact region (23) in the reverse direction of the first element (11) is moved through the actuating member (31) When compressing the second elastic member (14, 16) against the second abutment region in the opposite direction, the conditionally actuated friction device causes a friction torque between the first and second elements. A conditionally actuated friction device adapted to exert,
Including torsional damper.   The at least one second elastic member (14, 16) is opposite the second contact region in the forward direction of the second element (9, 10) at the rest position of the torsional damper (1). The torsional damper (1) according to claim 1, wherein the torsional damper (1) is pre-compressed with a second abutment region in the direction.   The at least one second elastic member (14, 16) has a second contact region in a direction opposite to the second contact region in the forward direction of the second element (9, 10) in the rest position. The pre-compressed second elastic device with a pre-compression value between the first and second elements (11) in the reverse direction for transmission of resistance torque. The second elastic member (14, 16) is in contact with the second contact region in the reverse direction of the second element (9, 10) via the operating member (31). The torsional damper (1) according to claim 2, wherein the torsional damper (1) is adapted to exert a return torque that is greater than the friction torque generated by the conditionally actuated friction device.   4. The device according to claim 1, wherein at the rest position of the torsional damper (1), the first elastic device is not pre-compressed or pre-compressed with a pre-compression value of less than 5 Nm. The torsional damper (1) according to item.   The rigidity of the first elastic device and the circumferential direction between the second elastic member (14, 16) and the second contact region (22) in the forward direction of the first element (11). The clearance j is the torsional damper (1) according to any one of claims 1 to 4, wherein the forward torque threshold is in a range of 10 to 60 Nm.   When the second elastic member (14, 16) is at a rest position of the torsional damper (1), the circumference of the second contact region (23) in the reverse direction of the second element (9, 10) is The second elastic member (14, 16) is separated by the gap k in the direction, and the first and first elastic members (14, 16) are only when the resistance torque equal to or greater than the reverse direction torque threshold is transmitted from the output element to the input element. The torsional damper (1) according to any one of the preceding claims, wherein the torsional damper (1) is adapted to be compressed between a second abutment region in the opposite direction of the two elements.   Between the rigidity of the first elastic member (15, 17) and the second contact region in the reverse direction of the second elastic member (14, 16) and the second element (9, 10). The circumferential clearance k of the torsional damper (1) according to claim 6, wherein the torque threshold in the reverse direction is in a range of 5 to 30 Nm.   One of the first and second elements includes a cover (11), and the other of the first and second elements is two guide rings (9, 9) disposed on both sides of the cover (11), respectively. The torsional damper (1) according to any one of the preceding claims, comprising 10).   The conditionally actuated friction device includes an actuating ring (24) that supports the actuating member (31), wherein the actuating ring includes the first friction with or without a circumferential gap. The torsional damper (1) according to any one of the preceding claims, wherein the torsional damper (1) is rotationally coupled to the ring (25).   10. The torsional damper (1) according to any one of the preceding claims, wherein the conditionally actuated friction device is configured to be operated exclusively during transmission of resistance torque.   An upstream portion with a heat engine, a downstream portion with a generator, and a torsional damper (1) according to any one of claims 1 to 9, wherein the input of the torsional damper (1) A transmission mechanism of a motor vehicle in which an element is coupled to the upstream part and an output element of the torsional damper (1) is coupled to the downstream part.