FR2461161A1 - Automobile disc brake pad - has lining on back plate with corner lugs which locate ends of curved blade packing spring - Google Patents

Abstract

The automobile disc brake pad comprises a friction liner (12) on a mounting plate (11). The plate incorporates a packing spring (17). 'L' shaped lugs (13) project from two adjacent plate (11) corners, extending the major plate plane, and forming notches (15) which locate the extremities of a curved blade spring (17). The spring prevents operational pad float, may be prestressed, and may arch between its points of support (15). The ends of the spring have rectangular notches which house onto the lugs (13), may return in a 'U' shape to wedge in the notches or may be straight and lodge in 'V' section notches.

Description

The present invention relates generally to brake pads, in particular for a motor vehicle, whether they are pads intended for brake equipment whose rotary member to be braked is generally in the form of a disc, or that these are pads intended for brake equipment whose rotary member to be braked is generally in the form of a crown.

 In both cases, such a brake shoe usually comprises a support plate, generally metallic, and a friction lining suitably attached to this support plate, for example by gluing.

 your present invention relates more particularly to these brake pads which, in place on the brake which they equip, are inserted in a housing, which is suitable for their guidance with respect to the rotary member to be braked, perpendicular to it in the case of a disc, parallel to a median radial plane of this rotary member to be braked in the case of a crown, and which, parallel to the corresponding guide direction, comprise at least one stop suitable for supporting such a brake shoe.

Usually, to avoid untimely formation of noise due to the parasitic movement which may be the object in its housing such a brake shoe due for example to vibrations, it is usual to associate with this brake shoe a spring urging it in. permanently applied against the corresponding support stop.

te more often, to date, this spring forms a separate part of the brake shoe.

 This is the case in particular in French patent No 1.431.?45.

This results in various drawbacks.

 First of all, the installation of this spring on the brake to be fitted requires special handling, and the assembly of the assembly is more complicated.

 In addition, the spring associated with the brake shoe is usually fixed relative to the support of the assembly while this shoe moves with respect to the latter as the wear of its friction lining , it follows on the one hand that there is a friction contact, wear generator and likely to be the cause of incidents, between the brake shoe and the spring associated with it, and d on the other hand that, in order to be able to act effectively on the brake shoe throughout the lifetime of the latter, which moves relative to it, it must have a transversely much larger dimension to that actually necessary for it to deploy the desired elastic force on this brake shoe.

Finally, when changing the brake shoe after wear of its friction lining, the spring associated with it, assuming that it has remained correctly in place and that it is therefore still thus available, which is not certain, is not necessarily systematically changed, whereas, because of the constraints which are its own in service, and in particular because of the heating of which it is inevitably the object and which is likely to lead by tempera to a modification of its characteristics, it may no longer be able to correctly ensure the elastic maintenance in its housing of the new braking pad installed.

To avoid these drawbacks, the present invention generally relates to an arrangement according to which the spring associated with a brake shoe is permanently attached thereto.

 In French Patent No. 2,296,127, it has certainly been proposed to subject such a spring permanently to a brake shoe.

However, according to the specific arrangement described in this patent, this spring is carried by a pin mounted transversely on the support plate of the brake shoe concerned.

 This results in the need to implement an additional piece, namely the pawn in question.

It also results therefrom that the leaf spring subject to the relevant brake shoe is offset transversely with respect to the support plate of this brake shoe, and therefore vis-à-vis the bearing stop against which the latter bears. , which leads, for the brake shoe, to a tilting torque such as to affect its good sliding vis-à-vis the rotary member to be braked.

The present invention relates to a brake shoe permanently comprising a spring and free from these drawbacks.

This brake shoe, which is therefore of the type comprising a support plate and a friction lining suitably attached thereto, and to which it is associated with a spring remains, is characterized in that said support plate comprises two transversely shoulders retaining generally turned towards each other, and in that said spring extends in a arch between said retaining shoulders; preferably it is a spring leaf.

In practice, this leaf spring is prestressed, which is sufficient to maintain it on the brake shoe concerned.

It can for example be simply braced by its ends between the retaining shoulders of the support plate.

 However, as a variant, various provisions can be adopted to further subject its maintenance.

 Anyway, the establishment of such a leaf spring on the brake shoe concerned does not imply the implementation of any additional part, and it directly deploys its effects on the support plate of this brake shoe, plumb with the support stop against which the latter bears, and therefore without generating any disturbing tilting torque.

Your characteristics and advantages of the invention will also emerge from the description which follows, by way of example, with reference to the appended schematic drawings in which
Figure 1 is a perspective view of a first type of brake shoe to which the invention is applied, according to a first form of implementation thereof
Figure 2 is a plan view of this brake shoe, along arrow II of Figure I
Figure 3 is a side view, along arrow III of Figure 1
Figure 4 is a view similar to that of Figure 1 for a second type of brake shoe, and according to a second embodiment of the invention
Figure 5 is a side view of this brake shoe, according to arrow V in Figure 4
Figure 6 is a plan view, along arrow VI of Figure 4
Figures 7 and 8 are partial views similar to that of Figure 2 and each relate respectively to an alternative embodiment
Figure 9 is a perspective view of a third type of brake shoe to which the invention is applied.

 FIG. 1 illustrates by way of example, the application of the invention to a brake shoe intended for equipping a brake, the rotary member of which to be braked is generally in the form of a crown, and more precisely targets that braking pads of such a brake which must bear on the external cylindrical surface of such a ring.

 Such a brake shoe, designated by the references 10 in FIGS. 1 to 3, generally comprises a support plate II, of cylindrical shape adapted to that of the crown of the brake to be fitted, and a lining. friction 12, suitably attached to the concave face of the support plate 11, for example by gluing, and itself having, on the surface, a concave cylindrical contour.

 In plan, Figure 2, the support plate It has a generally rectangular outline, and, in the embodiment shown, it has projecting, in two adjacent its corners located at the ends of the same of its curved edges, two pins 13.

 By means of these lugs 13 are formed two shoulders 14, which are coplanar with each other, and which are intended to cooperate in abutment with a stop surface provided for this purpose on the fixed support of the brake fitted, in the housing thereof intended to receive the brake pad 10 concerned.

In addition, through the lugs 13, are also formed, transversely, two retaining shoulders 15 which are therefore formed on the edge of the support plate 11, and which are generally turned towards each other, parallel to the axis of curvature thereof.

 According to the invention, such a brake shoe 10, it is permanently associated with a spring 17, and the latter extends in a bend between the retaining shoulders 15 of the support plate II; in practice, and as shown, this spring 17 is constituted by a leaf spring, and the ends thereof are arranged at the root of the retaining shoulders 15 in the corner zones which these form with the curved edge. 16 corresponding to the support plate II.

 Preferably, this spring leaf 17 is prestressed, that is to say that, in place between the retaining shoulders 15 of the support plate 11, its configuration has a more pronounced curvature than that of its configuration at rest. , as illustrated in broken lines in Figure 2; for this rest configuration, the leaf spring 17 could moreover be flat.

 The pretension thus applied to the spring leaf 17 is normally sufficient to maintain the latter, as illustrated in FIGS. 1 to 3.

 In this case, the spring leaf 17 is therefore simply arched at its ends between the retaining shoulders 15 of the support plate 11.

FIGS. 4 to 6 illustrate the application of the invention to that of the brake pads intended for equipping a brake, the rotary member of which to be braked is in the general shape of a crown which must bear on the internal surface of such a crown.

 This brake shoe, designated by the general reference 18 in Figures 4 to 6, comprises a curved support plate 19, formed of three successive flat sections in the embodiment shown, and a friction lining 20 suitably attached , for example by gluing, on the convex face of this support plate 19.

 As before, on the support plate 19 are formed transversely, two retaining shoulders 21 generally turned towards one another, and, between these retaining shoulders extends in a hanger, permanently, a spring leaf 23.

As before, such a leaf spring 23, which is prestressed, could simply be braced by its ends between the retaining shoulders 21.

 However, as a variant, and as shown, each of the ends of the spring leaf 23 has a notch 24 by which it is engaged on the edge of the support plate 19, at the root of the retaining shoulder 21 corresponding to this one.

You hold the spring leaf 23 parallel to a direction perpendicular to the plane median section of the support plate 19 is advantageously strengthened.

According to the variant embodiment illustrated in FIG. 7, which is by way of example applied to the spring leaf 17 and which could equally well concern the spring leaf 23, at least one of the ends of such a leaf of spring, and in practice each of these is hemmed in the general form of a butt, and the corresponding retaining shoulder 15 of the support plate te concerned is framed by two retaining shoulders 26 ′, 26 "of said plate support 11; in practice, in the embodiment shown, such a retaining shoulder 26 'is formed by the corresponding end of the curved edge 16 concerned of the support plate 11.

Between the two retaining shoulders 26 ', 28 ", the hemmed end of the spring leaf 17, which is elastically deformable, is prestressed, which contributes to the maintenance of this spring leaf.

According to the variant embodiment illustrated in FIG. 8, which can also be applied to any type of spring leaf, each retaining shoulder 15 of the support plate 11 concerned is at least partially folded down by crimping in the direction of 1 1 corresponding end of the spring leaf 17, as shown diagrammatically by arrows F in this FIG. 8.

the retention of the spring leaf concerned is also strengthened.

 FIG. 9 illustrates the application of the invention to a brake shoe 28 intended for equipping a brake, the rotary member of which to be braked is in the general shape of a disc.

Such a brake shoe 28 comprises a generally flat support plate 29, and a friction lining 30 suitably attached, for example by gluing, on one of the faces thereof.

As before, two retaining shoulders 32 facing one another are provided transversely on the support plate 29, for example by means of lugs 33 which projecting therefrom, in the same direction, at two corners adjacent to its outline.

 According to the invention, between these retaining shoulders 32 extends in a hanger, under prestressing, a spring leaf 34.

In the example embodiment shown, this leaf spring 34 is of the type described with reference to FIGS. 1 to 3.

 However, as a variant, it may equally be a spring leaf of the type of that described with reference to FIGS. 4 to 6, or of that described with reference to FIG. 7.

 The arrangement of Figure 8 can also be adopted.

 The present invention is moreover not limited to the embodiments described and shown, but encompasses any variant embodiment and / or combination of their various elements.

In particular, the spring used is not necessarily constituted by a leaf spring, although this is a particularly simple and economical embodiment; it could in fact be for example constituted by a hairpin spring, with one or more strands.

 In addition, the retaining shoulders between which extends such a spring are not necessarily formed on the edge of the support pad of the brake shoe concerned; they could for example be formed on bosses attached to this support plate or forming an integral part thereof.

Claims (8)

 1. Brake shoe, of the type comprising a support plate and a friction lining suitably attached thereto, and to which it is permanently associated with a spring, characterized in that said plate comprises transversely two generally turned retaining shoulders l 'towards each other, and in that said spring which is preferably a leaf spring extends in a bend between said retaining shoulders. 2. Brake shoe according to claim 1, characterized in that the spring is prestressed. 3. Brake shoe according to any one of claims 1, 2, characterized in that the spring is simply braced by its ends between the retaining shoulders of the support plate.  4. Brake shoe according to any one of claims 1 to 3, characterized in that, at at least one of its ends, and preferably at each of these, the spring is hemmed in the general shape of a butt .  5. Brake shoe according to claim 4, characterized in that a hemmed end of the spring is elastically deformable and the corresponding retaining shoulder of the support plate is framed by two retaining shoulders between which said hemmed end is prestressed. .  6. Brake shoe according to any one of claims 1 to 5, characterized in that a retaining shoulder of the support plate is at least partially folded down by crimping in the direction of the corresponding end of the spring.  7. Brake shoe according to any one of Claims 1 to 6, characterized in that the retaining shoulders of the support plate are formed on the edge of the latter. 8. Brake shoe according to claim 7, wherein the ends of the spring each have a notch, characterized in that, by such a notch, the spring is engaged on the edge of the support plate.