CA1181701A - Disc brake anti-rattle means - Google Patents

Abstract

DISC BRAKE ANTI-RATTLE MEANS
Abstract of the Disclosure An anti-rattle clip is comprised of a length of spring wire formed to provide two spaced clip legs joined by an intermediate segment. Each clip leg is formed adjacent the intermediate segment to abut spaced areas of the radially outer edge of a friction pad backing plate and the ends of the clip legs are formed to abut spaced areas of the radially outer edge of the other friction pad backing plate. Segments of the clip legs between the segments abutting the friction pad backing plates are formed to extend radially inward and under the circumferentially spaced edges of an aperture provided to the disc brake caliper bridge.

Description

DISC BRAKE ANTI-RATTLE MEANS
BaclcF~round of th~ Invention Field of the Inven~ion. The present irlventior~
relates to a disc bra~e assembly and more specifically to an improved means for bia~ing friction pads into abutment witb supporting means in the disc brake as~embly.
The present inventio~ is particularly applicable to a disc brake assembly of the type which includes a rotor or disc mounted for rotation with a vehicle wheel and a 10 floating caliper ~traddling the periphery of tltle rotor.
The caLiper is usually mounted on a support or torque pLa~e by mea~s permit~ing movemen~ of the caliper in arl axial direction relative to the torque plate and ro~orc Brake pads are carried by the caliper on oppo~ite sides of the .
lS rotor and are movable into contact with oppositely disposed friction braking ~urfaces of the rotor by means of a suitable actuating mechanism wbich is usually driven by a fluid motor. In a floating caliper disc brake, eac~
friction pad i~ located intermediate one leg of the caliper and the adjacent friction surface o~ the rotor. The brake pad supporting mean~ is designed to permit axial movement of the brake pads and, without further restraint, the friction pads may vibrate against the supporting means or "rattle" when t~e assembLy is not actuated~ The actuating mechanism is usually carried by one leg of the caliper and serves to move the ~riction pad adjacent to that leg axialLy into contact with t~e rotor, che reac~ion force of the contact serving co draw the other leg of the caliper and the o~her friction pad inco contact wic~ ~he opposite surface o the roror.
DescripCion o~ t~e Prior Art. Various anti-ra~tle devices for di3c brake friction pads are disclo~ed in U.S. ~atent Nos. 4,L94,597; 3,056,174;
3,972,393; 4,049,087 and 3,027,751. Some of these require means sucb as rivets, aper~ure~ or rece~es on the riction pad assembly for attaching the an~i-rat~le device to ~hc friction pad. Other anti-ra~tle devices are disposed 10 between the friction pad.backing plate edge a~d t~e ~upporting mean~ and are noC readily accessible for removal or replacemcnt.
The pre~ent invention avoids the~e prob1ems by providi~g an anti-r~ttle:spring clip ea~ily acce3~ible for removal and replacement purpose~ which does not require spec;al attaching mean~ on the friction pad backing plate~.
Summary of the Ir~vent;on According to the invention there is provided an anti-rattle spring clip for a disc brake comprising an elongate element formed to provide two spaced leg segments joined by an intermediate segment, each of said leg segments adjacent said intermediate segment of said element comprising means formed to abut a radially outer edge of a first frict.ion pad, the ends of said leg seg-ments comprising means formed to abut a radially outer edge of a second friction pad and stabilizing means formed in each of said legs between said means formed to abut said first friction pad and said means formed to abut said second friction pad.

Other aspects of the invention are described and claimed in copending Canadian pa~.ent application Serial No. 388,~78 filed on October 27, 1981, of which the present application is a division.
T~e advantages offered by tbe present invention will become apparent from the following description of the embodiment stlown in ~e accompanying dras~-ings.
~9 ~
In the drawings, wberein like reference numerals refer to like parts:
Figure 1 i~ a side elevation of a disc brake incorporating the present inve~ior~;
Figure 2 is a front elevation view of ~be disc brake as~embly of Figure l;
Figure 3 is a perspective v iew of the anti-rattle spring 'lip; and Figure 4 is a v iew partly in sec~ion taken along the linP 4-4 of Figure 2.
Description of the Invention With reference ~o the drawings, Figures 1 and 2 show a disc brake assembly generally designated by the numeraL 10. The assembly 10 includes a floating caliper 12 mounted by means of circumEerentially spaced, axially aligned pair~ o bosses 14 and lS, and 16 and 17 on slide pins 19 and 20. The slide pins 19 and 20 are respeccively secured by a draw keys 23 within bores provided to bosses 21, 22 at che radially outPr excremicie~ of circumferencially spaced, radially ex~endin~ arm3 24, 25 of --4~
the brake supporting torque plate or spider 26. The torque plate 26 is provided with a circular array of apertures 28 which receive a plurality of bolts not shown which in turn secure the support or torque plate 26 to a 1ange weld~d to S a vehicle axle 29. The torque plate 26 could of course be welded directiy to the axle 29. A rotor 30 having axially spaced, radially extending3 oppositely disposed friction braking surfaces 31 and 32 is secured for ro~ation with a w~eel hub ~not shown) carried by t~e vebicle axle 29 adjacent the disc brake assembly 10.
The caliper 12 i~ a cast metal component comprised of a depending leg 40 extending radially inward adjacent the friction surface 32 of rotor 30, an oppo~itely disposed depending 12g or wall 41 adjacent t~e fric~ion 15 surface 31 of ro~or 30 and a bridge 42 ~traddLir~g tbe periphery of rotor 30 and joining the leg 40 ~o the wall 41. The walL 41 i5 formed wi~ a generally cylindrieal housing 44 baving a borc 45 slidably mounting a piston 43 formed integral:Ly with a load applying plate 47. The 20 cootour of the :Load plate 47 i~ similar to the contour of the backing plate 35 of the rictio~ pad 34 and moves the pad 34 axially into contact wi~h the rotor f~icti~n surface 31 in response to actua~ion of ~he bra~e a~sembly. The piston 43 and l~ad plate 47 may be moved by suitable 25 ~ydraulic or mechanical actuating means, not sho~n. The bridge 42 of caliper 12 is pro~ided with an aperture 46 defined by a radially disposed edge 48 and a pair of circumferentially spaced,axially extending, radially converging edges 50 and 51. The circumferentially spaced edges SO, 51 converge in a radial direction at an included angle o~ abou~ 32 degree~. The circumferentially spaced edges 50, SL are each provided with a slot 52, 54. The bottoms 56, 58 of the slots S2, 54 are substantially parallel and t~e slots S2, 54 are located radially outward from the periphery o~ the rotor 30 so as to extend at Leas~
partly across the periphery of the rotor 30 as best shown by Figure 2 .
Friction pads 34, 37 are respectively comprised 7~

- of backing plate~ 35, 38 with ~riction material 36, 39 secured thereto. The backing places 38 also include abutment surface~ 61, 62 adjacent the radially converging edges 65 and 66, respectively. The abutment surfaces 71, S 72 extend only a short radial distance relacive to the length of the radially converging edges 65 and 66. T~e friction pads 34, 37 are axially located between t~e depending portion~ 40, 41 of the caliper 12. Friction pad 34 is axially located between the load plate 47 and friction ~urfaçe 31 of the rotor 30. Friction pad 37 i5 axially located between the friction surface 32 of rotor 30 and the caLiper leg 40. In Figure~ L and 2, t~e friction pad~ 34, 37 are hown opera~ively locat d adjacent the oppositely disposed fr1ction ~urfaces 31, 32 of rotor 30 L5 wi~h the fric~ion material 36, 39~ respectively, facing the surface~ 31, 32.
The friction pads 34, 37 are suppo~ted by means of radially extending ~b~ 64 and 67. The f~iction pad bac~.ing pLate tabs 64 and 67 are respectively bounded.by circumferentially spaced, radially converging edges~65, 66 and 68, 69 which are slidably carried by ~e circumferentialLy. spaced edges 50, 51 of the caliper aperture 46. S~allow slots 73, 74 and 75, 76 are provided to ~he radially outer edge~ of friction pad tab~ 64 and 67, respectively. The circumferentially spaced edges 65, 66 of friction pad tab 64 and edges 68, 69 of friction pad ~ab 67 converge at an angle substantially ~he same as t~e included angle provided to the radially converging ed~e~ 50, 51 of caliper aperture 46 ~o permit ~he friction pad tabs 64 and 67 to ~lide freeLy along the edges 50 and 51. The abutment surfaces 61, 62 of friction pad backing plate 35~and the abutment surfaces 71, 72 of backing plate 38 abut the radially inner surface 13 of the caLiper 12 adjacent t~e aperture edges 50, 51 to radialLy loca~e the riction pads relative to the surface 13. The circu~ferentially spaced, axially extending, radially converging edges 50, 51 of caliper aperture 46 ~hus support che tabs 64, 67 of friction pads 34, 37 in their respeccive operative ,- position~ adjacent the oppositely disposed friction surfaces of the rotor 30.
The slots 52, 54 are respectively provided throug~ the circumferentially spaced edges 50, 51 to provide an additional clearance or length which when taken together with ~he circumferential length o the caLiper aperture 46, i~ adequa~e to radially inwardly pass the tabs 64, 67, respectively, of fric~ion pads 34, 37 and thereby permic installacion and removal of ~he friction pad3 34, 37. The width of the slots 52, 54 î~ slightly greater than 10 the thickness of the friction pad backing plate tabs 64, 67 and ~he ~lo~ 52, 54 are axially located radislly outward of the peripbery of the rotor 30 ~o preven~ the backi~g plate tabs 64, 67 from accidentally o~ inadvert~ntly becoming aligned wi~h the access slots 52, 54 when the 15 riction pad~ 34, 37 are re~pecti-rely in ~heir s~perative positions ad3acent the oppositely dis~osed fric~ion surfaces 31, 32 of roto~ 30.
An an~i-rattle spring clip 80 is dispo~ed within the aperture 46. As best shown by Figure 3, the anti-ra~tle cL;p 80 is preferably formed ~rom a continuou~
Length of spr;ng steel wire to provide two gpaced leg segments 81, 82 joined by an intermediate segment 84. The clip legs 81 and 82 are respec~ively formed adjacent the intermediate segment 84 to provide raised U-shaped bends 85 2S and 86 adapt~d to abut circumferentially spaced areas of the radially outer edge of friction pad tab 67. The distal ends 87, 88 of the clip leg~ are raised to the same level as the bends 85, 86 to abut circumferentially spaced area~
of the radially outer edge of friction pad tab 64. The clip leg bends 87, 88 are substantially coplanar with ~he closed end of the U-shaped bends 85, 86. The leg ends 87, 88 extend a substantial distance, approximately 5.5 centimeters, to permit the friction pad 34 to move toward the friction pad 37 while maintaining contact between the leg ends 87, 88 and friction pad tab 64 as the fric~ion Living material wears.

The clip legs 8L, 82 are respectively formed intermcdiate the U-bends 85, 86 a~d the ends 87, 88 with laceraLly projecting stabilizing means ~1, 92. The stabilizing meanq 91, 92 are found to extend laterally away S Erom each other in substantially the ~ame plane which i3 spaced downward or radially inward (Figure 4) from the pLane of ~he U-bends 85, 86 and the leg ends 87, 88. As best s~o~n by Figure~ 2 and 4, the stabilizing means 91, 92 extend under the aperture edges 50, 51 to engage the ~0 undersurface of tbe caliper bridge 42. T~ orsionally loads the spring clip 80 and provides a orce in U-bends 85, 86 and leg end~ 87, 88 biasing the tab~ 64 and 67 radially inward ~o force the circumferentially spaced edge of the tabs into abutment wit~ t~e aperture edges 50 ~ 51n The spring clip 80 may be easily înstalled by disposing the U-bends 85, 86 over ~he radially outer edge of the friction pad tab 67 until tbey seae in the grooves 75, 76. One of the seabilizing means 91, 92 is positioned under its corre~pondi~g aperture edge and the clip leg ends are moved toward one another until the other s~abilizing means clears it:s corre~ponding aperture edge and ca~ be released to ext:end lateral~y beneath ~hat edge surface.
The leg ends 87, 88 are then sea~ed ;n the shallow grooves 73, 74 provided to tbe radially outer edge of friction pad tab 64.
The present invention thus provides a simple economical means for biaqîng the friction pads into bearing abutment with the supporting edge~ of the caliper aperture to prevent the friction pad backing plates from vibrating against the supporting edges when the brake assembly is not actuated. The anti-rattle spring clip is also readily accessible through the caliper aperture.
The invention may also be embodied in other specific ~orms ~ithout deparcing from the spirit or essential characteristics thereof. The foregoing description is therefore to be considered as iLluscrative and noc restricti~e, the scope of the inventio~ being _ de~ined by the appended claims and all changes which come within the meaning and range o equivalency of the cLaims are therefore intended to be embra.ed t~ereby.

Claims (4)

Claims:

1. An anti-rattle spring clip for a disc brake comprising an elongate element formed to provide two spaced leg segments joined by an intermediate segment, each of said leg segments adjacent said intermediate segment of said element comprising means formed to abut a radially outer edge of a first friction pad, the ends of said leg segments comprising means formed to abut a radially outer edge of a second friction pad and stabil-izing means formed in each of said legs between said means formed to abut said first friction pad and said means formed to abut said second friction pad.

2. The anti-rattle spring clip defined by Claim 1 wherein said elongate element is a length of spring wire.

3. The anti-rattle spring clip defined by Claim 1 wherein said stabilizing means comprise a segment of each leg formed to extend in a direction away from the other said leg in substantially the same plane as the stabilizing means of said other leg.

4. The anti-rattle spring clip defined by Claim 1 wherein said stabilizing means comprise segments of said legs formed to extend in opposite directions away from each other in substantially one plane and said means formed to abut the radially outer edges of said first and said second friction pads are substantially in a second plane spaced from said one plane.