WO2018002499A1

WO2018002499A1 - Torque-damping device for a motor vehicle and hydrokinetic apparatus comprising such a device

Info

Publication number: WO2018002499A1
Application number: PCT/FR2017/051694
Authority: WO
Inventors: Michaël Hennebelle
Original assignee: Valeo Embrayages
Priority date: 2016-06-28
Filing date: 2017-06-26
Publication date: 2018-01-04
Also published as: FR3053089A1; FR3053089B1

Abstract

The invention relates to a damping device with a plurality of compression stages, comprising at least two coaxial washers, an inner radial phasing washer (1) and a protruding radial guide washer (2), respectively, said washers having a relative angular displacement and said radially protruding washer (2) being provided with peripheral recesses (10, 20) for helical springs (R1, R2) having, at the longitudinal ends thereof, transverse bearing surfaces (10a, 22a) which define intermediate connection areas, characterised in that at least one of said intermediate connection areas of the protruding washer (2) is extended radially by a tab (21) intended for moving circumferentially in a notch (12) arranged facing same on the perimeter of said inner washer (1) and abutting against the longitudinal end edges (12a) thereof in order to limit the displacement travel; and a hydrokinetic apparatus provided with such a device.

Description

Torque damping device for a motor vehicle and hydrokinetic apparatus comprising such a device

The invention relates to a damping device, particularly in torsion, for a motor vehicle.

In particular, the invention relates to an improvement of torsional dampers with two stages of springs and a hydrokinetic apparatus comprising such a damper.

SUMMARY OF THE INVENTION [0001] A torque damping device for a motor vehicle comprises, in a conventional manner, a torque input member for coupling to a drive shaft, a torque output member for coupled to an input shaft of a gearbox; the torque output member and the torque input member being rotatable relative to each other about an axis, and resilient means mounted between the torque input member and the torque output element.

[0002] Furthermore, an explosion engine generates acyclisms because of successive explosions in the engine cylinders, these acyclisms varying in particular as a function of the number of cylinders.

Elastic means such as coil springs allow, in particular, to dampen such acyclisms.

The springs are generally housed in cavities or windows in the washers and which extend circumferentially or in substantially orthoradial directions. In the presence of a driving torque, the washers are subjected to tangential forces leading to compression of the springs and a relative angular movement of the two washers. It is often preferable to avoid that the turns of said springs are contiguous during operation of the device, so as to avoid any degradation of the performance of said springs.

However, the turns of the springs become contiguous when the torque transmitted by the damper is too large, and these turns are then crushed thus causing fatigue and premature wear of the springs.

The limitation of the angular displacement by means of abutments makes it possible in particular to avoid such a phenomenon. Such integrated damping device is described, in particular, in FR 2972035 and FR 2972036 which describe torsion dampers associated with two guide washers and an interposed web.

In these dampers, the compression of the springs is limited by limit stops which cooperate with the ends of the springs and which are formed on parts intended to be attached to at least one of the washers and fixed between the housing of the springs. by means of rivets.

However, this embodiment is problematic not only from an economic and logistical point of view because it is necessary to manufacture an independent piece but also on an industrial level because this piece must then be riveted on one side. washers and adds weight to the torsion damper.

In addition, this solution is not suitable for dampers in which the guide ring and the phasing washer or the web do not have the same structure and whose diameters are significantly different.

Indeed, in such dampers, the inner washer said phasing has a diameter smaller than that of the said guide washer and is mounted coaxially on the latter which requires a specific arrangement of the stops to not interfere with their freedom angular deflection. The invention aims to provide a simple, effective and economical alternative to torque transmission devices of the prior art while overcoming the aforementioned technical problems.

For this purpose, the invention proposes modifications of the respective structures of the washers so as to integrate the end stops optimally and without causing overload or harmful interference between the washers and / or the web.

This object is achieved, according to the invention, by means of a multi-stage compression damping device comprising at least two coaxial washers, respectively a radially inner phasing washer and a radially protruding guide washer, said washers having a freedom of relative angular displacement, said protruding washer being provided with peripheral helical coil receiving housings having, at their longitudinal ends, transverse bearing faces which delimit inter-connecting zones, characterized in that at least one one of said intermediate zones of the protruding washer is extended radially by an orthogonal tab intended to move circumferentially in a notch arranged opposite said inner washer and abutting against the edges of the inner washer to limit the stroke of the displacement. .

According to a first variant, the tab is intended to move circumferentially in the notch arranged facing the periphery of said inner washer and to abut against its longitudinal end edges to limit the travel of the travel.

According to this first variant, the intermediate connection areas of the protruding washer comprise bosses. According to an advantageous characteristic, the tab extends substantially parallel to the axis of angular movement of the washers.

According to a specific characteristic, the lug of the protruding washer has a height greater than or equal to the thickness of said inner washer. According to another variant, the damping device comprises several compression stages, and the inner washer is provided with peripheral housings for helical springs having, at their longitudinal ends, transverse support faces which delimit zones of interleaving.

According to an advantageous characteristic, the notch of the inner washer is centered on the central axis of the corresponding intermediate connection zone of said inner washer.

Preferably, the housing of the springs of the inner washer are in the form of through windows. The springs of the projecting washer are in the form of at least partially tubular cavities.

Advantageously, the tab and the notch are arranged in the radial spacer between the peripheral housing of the inner washer and the peripheral housing of the protruding washer. Thus it is possible to arrange the abutment means in a restricted space, between two rows of spring.

According to another characteristic, the tab of the projecting washer is connected to the interposed connecting zone opposite via bent portions.

According to another characteristic, the projecting washer has through holes made at the right of the legs.

According to a specific variant, the tab is made in one piece with the protruding washer.

According to a preferred embodiment, the projecting washer has three equidistant tabs cooperating with three corresponding notches carried by said inner washer.

According to a variant, the inter-connecting zone is perforated to allow a deflection of the tab during the abutment of the projecting and inner washers. Another object of the invention is a hydrokinetic motor vehicle apparatus comprising a damping device as defined above.

The device of the invention facilitates the manufacturing process and the assembly operations of the components of the damper due to the integration of means ensuring the end stops directly on the washers and avoiding thus blocking the springs.

Furthermore, the guide washers and phasing retain their intrinsic mechanical properties since no additional part is reported. In addition, the device of the invention provides a significant gain in efficiency of the springs while extending their life due to the protection provided to the springs of the first stage in case of overtorque.

BRIEF DESCRIPTION OF THE FIGURES

Other features and advantages of the invention will become apparent from reading the description which follows, with reference to the accompanying figures and detailed below.

Figure 1 shows an exploded perspective view of an embodiment of the torsion damper according to the invention.

FIG. 2 is a perspective view from above of the guide washer of the device of the invention according to the embodiment of FIG. 1.

FIG. 3 is a view from below of the guide washer 4 of FIG. 1.

FIGS. 4A and 4B are detailed views, respectively, from above of the guide washer and in partial section along plane I II-111 (FIG. 3) of the damper.

Figure 5 is a perspective view from above of the arrangement of the inner washer 1 and the guide ring 2, without the springs.

For the sake of clarity, identical or similar elements are marked with identical reference signs throughout the figures. DETAILED DESCRIPTION OF EMBODIMENTS

Of course, the embodiments illustrated by the figures presented above and described below are given by way of non-limiting examples. It is explicitly planned that we can combine these different modes to propose others.

Torque damping devices for motor vehicles are intended to filter vibrations from the engine.

They comprise, in the traditional way, a torque input element intended to be coupled to a motor shaft, a torque output element intended to be coupled to an input shaft of a gearbox (no represented here), via a damping device.

In the field to which the invention is concerned, the damping device may comprise several damping stages, each comprising a set of springs of determined stiffness. The torque output member and the torque input member are then rotatable relative to each other about an axis of revolution and the first stage and the second elastic damping stage. are connected in series between the torque input member and the torque output member.

In the embodiment illustrated in Figures 1 to 5, the damper has two stages with two rows of springs R1 and R2 e series. Each damping stage is here provided with at least one washer located axially on either side of resilient members associated with this damping stage, the forces passing in particular through said washers.

To transmit the torque between the two rows of springs, the damper comprises, firstly, a radially inner washer 1, called phasing, and secondly a washer 2 protruding or protruding, larger diameter , said guide, guiding the row of springs R2, as shown in Figures 1 and 5. These two washers are mounted in contact with each other and coaxially on the central hub possibly enclosing an intermediate outlet web 3. They have an angular freedom of movement relative to each other around the center. central axis of rotation (Figure 1). In this configuration, the projecting washer 2 forms a box in the center of which is disposed the inner washer 1, as illustrated in Figure 5, other cylindrical or annular components such as a guide washer 4 integral in rotation of the washer. 1 inside, come close this box, as shown in Figure 1. The guide ring 4 has tabs 41 through which the torque is transmitted from the R2 springs to the inner washer 1. The washer 4 here carries a pendulum damping system D provided with oscillating weights F.

Each of these washers 1 and 2 is, here, in the embodiments shown, provided with peripheral housing 10, 20 for receiving helical springs R1, R2 (shown schematically in Figure 1 and visible in section on the Figure 4B).

However, according to a variant of the invention, the inner washer 1 may be devoid of housing for springs and provide a traditional sail function.

Preferably, the housing 10 of the springs RI of the inner washer 1 are in the form of through windows while the housing 20 of the springs R2 of the protruding washer 2 are in the form of at least partially tubular cavities. The tubular walls of these housings 20 thus partially match the cylindrical outer envelope of the springs R2 forming eyelets, as shown in Figures 1 and 4B ensuring their transverse retention on the washer 2 even in the presence of high compressive stresses.

The housings 20 formed on the projecting washer 2 are positioned beyond the radius of the inner washer 1, as illustrated by the figures.

The housing 10, 20 have, at their longitudinal ends, transverse bearing faces and wedging springs RI, R2. On the inner washer 1, these bearing faces are constituted by the longitudinal edges 10a of the windows 10 associated with the peripheral crenellations of the web 3 also participating in maintaining the springs R1, as shown in FIG. 1.

On the projecting washer 2, the faces 22a of longitudinal support of the springs R2 delimit, between two adjacent springs, circumferential interlaying zones 22 formed here bosses 22b.

These bosses 22b are preferably made by local stamping of the washer 2 and here have a flat upper face extending substantially radially.

Where appropriate, the longitudinal retention of the R2 springs of the second stage is reinforced by the presence of reentrant tongues 23 formed on the projecting periphery 2a of the washer 2, as in the variant illustrated in FIG. 5.

The invention aims to improve the damping device by modifying the structure of the washers 1, 2 to incorporate means forming end stops. The changes that can be made to the components of the damping device taken separately or in combination, will be described in detail below.

In the presence of a couple, the washers are subjected to torsional stresses resulting in an angular movement of one relative to the other. The improvements provided by the invention are intended to ensure the limitation of the angular travel stroke between the two washers by avoiding the presence of reported functional elements.

For this purpose, at least one and, here the three intermediate connection zones 22, the protruding washer 2 are extended radially and towards the center by orthogonal tabs 21. These tabs are angularly equidistant and extend perpendicularly to the plane of the washer 2 in the direction of the washer 1 and thus substantially parallel to the axis of angular displacement of the washers 1, 2. The tabs 21 are intended to be housed and to move tangentially in notches 12 formed opposite the periphery of the inner washer 1, as shown in Figures 4B and 5.

This movement is preferably carried out without contact between the tabs 21 and the face of the notches 12 opposite and the tabs 21 have a height greater than or equal to the thickness of the inner washer 1 to not interfere with the other components.

At the end of the travel stroke, the lugs 21 then abut against the longitudinal end edges 12a of the notches 12 to limit the compression of the springs R2. The tabs 21 and the notch 12 are arranged in the radial spacer between the peripheral housing of the inner washer and the peripheral housing of the protruding washer. Thus it is possible to arrange the abutment means in a restricted space, between the two rows of spring RI and R2.

It is understood that, according to the invention, the length of the notches 12 and, alternatively, the width of the lugs 21 will be determined beforehand according to the length of the travel stroke allowable or sought for the springs used.

The notches 12 of the inner washer 1 are centered on the median axis of the circumferential interlaying zones located between two housings 10 adjacent springs RI. These notches extend beyond the longitudinal edges 10a of the windows 10.

The legs 21 of the protruding washer 2 are offset towards the center relative to the housing 20 and are connected to the bearing faces 22a R2 springs via curvilinear sections forming bent portions 21a (Figures 2 and 4a). This particular profile results in particular from an operation of shaping the tab 21 by folding from an initially flat washer. In the example shown, the folding is 90 degrees but this example is not limiting. This operation is facilitated by the presence, on the projecting washer 2, of through orifices 24 in which the tabs 21 extend before folding and which are then located at the right of the final position of the tabs 21.

According to a variant not shown, at least some of the interleaving zones 22 could be openwork to gain flexibility and allow simultaneous contact of the different equidistant tabs when abutting.

Claims

claims

Damping device, in particular in torsion, for a motor vehicle, comprising at least two coaxial washers, respectively a radially inner washer (1) for phasing and a radially projecting washer (2) for guiding, said washers having a relative angular freedom of movement , said radially protruding washer (2) being provided with peripheral housings (20) for helical springs (R2) having, at their longitudinal ends, transverse bearing faces (22a) which delimit inter-connecting zones, characterized in that at least one of said intermediate regions (22) of the projecting washer (2) is extended radially by a lug (21) intended to move circumferentially in a notch (12) arranged opposite said inner washer ( 1) and abutting against the edges (12a) of the inner washer to limit the stroke travel.

Device according to claim 1, characterized in that the lug (21) is intended to move circumferentially in the notch (12) arranged opposite the periphery of said inner washer (1) and abut against its edges. longitudinal ends (12a) to limit the stroke travel.

Device according to claim 1 or 2, characterized in that said intermediate regions (22) of the protruding washer (2) comprise bosses. Device according to one of claims 1 to 3, characterized in that said tab (21) extends substantially parallel to the axis of angular movement of the washers (1, 2).

Device according to one of the preceding claims, characterized in that said tab (21) has a height greater than or equal to the thickness of said inner washer (1).

Device according to one of the preceding claims, characterized in that it comprises several compression stages, and in that said inner washer (1) is provided with peripheral housings (10) for springs helical (RI) having, at their longitudinal ends, transverse bearing faces (12a) which delimit intercalary connection areas.

7. Device according to the preceding claim, characterized in that said notch (12) of the inner washer (1) is centered on the central axis of the intermediate connection zone of the inner washer.

8. Device according to one of claims 6 or 7, characterized in that said housing (10) of the springs (RI) of the inner washer (1) are in the form of through windows.

9. Device according to one of claims 6 to 8, characterized in that the lug and the notch are arranged in the intermediate radial space between the peripheral housing of the inner washer and the peripheral housing of the protruding washer.

10. Device according to one of the preceding claims, characterized in that said housing (20) of the springs (R2) of the protruding washer (2) are in the form of at least partially tubular cavities.

1 1. Device according to one of the preceding claims, characterized in that said lug (21) of the projecting washer (2) is connected to the intermediate connection zone (22) via bent portions (21a).

1 2. Device according to one of the preceding claims, characterized in that said protruding washer (2) has through holes (24) located at right tabs (21).

13. Device according to one of the preceding claims, characterized in that said lug (21) is formed in one piece with the protruding washer (2).

14. Device according to one of the preceding claims, characterized in that said projecting washer (2) comprises three lugs (21) equidistant cooperating with three notches (12) corresponding carried by said inner washer

(1) -

15. Hydrokinetic apparatus for a motor vehicle comprising a damping device according to one of the preceding claims.