GB2624774A

GB2624774A - Pad-holding spring and pad return spring assembly, pad assembly, brake caliper

Info

Publication number: GB2624774A
Application number: GB2315564.1A
Authority: GB
Inventors: D'alessio Davide; Bosis Alberto; Crippa Cristian; Carminati Mattia
Original assignee: Brembo SpA
Current assignee: Brembo SpA
Priority date: 2022-10-14
Filing date: 2023-10-11
Publication date: 2024-05-29
Also published as: GB2624534A

Abstract

A pad-holding spring 2 includes at least one C-shaped section 4 and is configured to be arranged between a brake pad guiding ear (111; fig. 4) and a brake caliper body so as to bias the brake pad in radial R-R and circumferential C-C directions relative to the brake disc (102; fig. 2). A pad return spring 3 is made from at least one wire which may include coils, and is configured to bias the brake pad in the axial direction A-A away from the brake disc. The pad return spring 3 comprises: an anchoring portion 8 connected to the c-shaped section 4, a coupling portion 10 configured to couple to the brake pad, and a linking arm 9 between the anchoring 8 and coupling 10 portions. The coupling portion 10 is elastically movable with respect to the anchoring portion 8 in the axial direction A-A between a retracted resting position and at least one advanced position towards said disc 102. Part 22 of the coupling portion 10 is arranged closer D2 to the c-shape than D1 an arm end portion 16 of the linking arm 9 connected to said coupling portion 8.

Description

"Pad-holding spring and pad return spring assembly, pad assembly, brake caliper" * * *

DESCRIPTION

[00 Field of the invention

[0002]. The present invention relates to a brake caliper spring assenii capable of biasing a brake pad in axial, circumferential, and radial directions to reduce vibration and move the pad away from the brake disc when braking is completed to eliminate or reduce the residual torque between the friction material and the brake disc-

[0003]. Background art

[0004]. Disc brake spring assemblies configured to elastically retain and bias at least one brake pad in a brake caliper are known. [0005]. In particular, dam-floats US20180223928, US 9677629, U58869950 and CN207989608U show spring assemblies having a pad-holding spring operatively connected to a pad return spring.

[0006]. Usually, pad-holding springs retain the pads inside their scats obtained the brake caliper without limiting the movement thereof in the axial direction. so as to reduce the vibrations thereof_ [0007]. The return spring instead bia r the brake pads away-from the d I sc affey. -ea c.h braking action sc to reduce or eliminate residual braking torque (residual due to undesired contacts between the pads and the brake disc with the brake deactivated.

[0008]. Some knpwh. solutions include spring assemblies in which the pad-holding spring is made in one piece with the pad. return spr.n.q. Such springs are melds from, a sinrie piece of shaped and bent sheet metal and thus it necessary to make different -,vpes sprinhis for each different field of apcJ. I cat ion of the disc bra. Such solutions are particularly disadvantageous in terms of production costs, since a specific sprino assembly is required for each different disc brake application.

[0009]. Other -' known solutions comprise spring assemblies in which the pad-holding spline-and the pad return spa big are made from separate shaped and bent pieces of sheet metal and are then assembled, The pad a E:iLLtTn springs can thus be custokized according. to the application requirements of the braking system. However, the employment of axial leaf springs, particular in the case of nigh- performance brake applications, raises issues of envelope and weight in negatively affecting the performance of the vehicle on which the brake is mounted - [0010]. Still otner solutions provide erring assemblies irr which the badehol-ttirox spring and the pan return spring are made from a shaped and bent piece of sheet metal and a wire spring, which are then assemtied. Solutions of this type are known, for example, from documents GB2257483 and U82013025981.

[0011] In these solutions, the wire pad return spring comprises an anchoring postLen adapted to be connected to the, pad-holding spring, a coupling portion adapted to be connected to the brake pad and movable at least between an axially advanced position. and an axially. retrac Led resting. position, ann an elastic return port ion, which. confle the anchoring portion and. the coupling cortion so as to constantly bias the coupling portion in. said axially retracted resting P sit. .-3. allowing the brake pad to be moved away the brake disc once the braking action is complete.

[0012]. In some of these solutions, it. was found that the:.ouplin portion is connected to a brake pad portion fass: the brake disc wi thout being tangentially constrained to the pad plate. in such solutions, it was found that the coupling portion of the spring can slide tangentially or cirxwmferentialiv on the a+ going-in the direction of the pad-holding spring.

[0013]. In paxticular, for examx:e during the assembly, the tangential sliding of the coupling portion on thP plate can cause the coupling portion between the edge of the plate and a wall of the pad-holding spring to uncouple from the pad itself or become wedged between the edge of the pad and the pad-holding spring, impairing the operation of the pad--holding spring and pad return sprirr assembly.

[0014]. Additionally, for example under conditions of.hi oh friction material wear, the tangential sliding of the coupling portion the PlCLte can bias, at ±eCLst partiasiy, the elastic return portion of the wire spring until it contacts a wall of the pad-holding spring facing the side edge-of a brake pad ear, generating friction between the elastic return portion and the pad-holding spring, which adversely affects the performance of the brake caliper.

[0015]. In particular, the sliding between a lamge surface of the wire pad retLj.rnsurinq and the pad-holdin 11 adversely affects the braking effi the servioc late, and the rd lability the wire rer.un. aping, ar.Lo. in particular. can cause the pad iwiv move away from the disc, leading to uneven wear of the brake pad. T-some cases, the fricticin between the spring arm portion is sn high that it stops the movement of the pad, wedging a portion of the wire spring between the brake Pad and the pad-holding spring.

[0016]. Therefore, in the industry the need o provide Tani-plding spring and pad return spring assemblies, the wire pad return spring is shaped so as to simply allow a greater pad return reliability, even. under advancedl wear rundiUons of the fri ct1 ma material, as well as a reduction in maintenance interventions, is strongly felt.

[0017]. Therefore, a need arises to manufacture spring assemblies, pad assemblies and brake calipers which are capable simultanecu.siy offeriac, durng the braking, pa-i-ti-cularly efficient. performance in reducing, or even suppressing, any residual torque at the end of braking, and vibration and aciae minimizaticn properties, while allowing high adaptability and ease of modification so as to he used in various fields of application, and desired performance of disc brakes without affecting time and costs during the design and manufacturing' [0018]. Therefore, it is the problem. underlyi the present invention to devise a spring assembly, a pad assembly and a brake caliper, which have structural and functional features such as to meet tha aforesaid needs whi le obriatina the drawbacks mentioned refeenee tn tire prior art and. meeting the aforesaid fe' needs.

[0019]. Solution.

[0020] Tt.is an oblect of Lhe resent 'invention f e a Dad-holding sprima, and pad return spring assembly, as well as a brake pad asserftily, as well as a brake cal i.rte.r which a ilow reducing, if not eliminating, the residual torque once a braining action is completed, and which allow Increasing the braking reL.LabIiity.

[0021]. These and other objects and advantage:: are achieved by a pad-holding spring and pad return spring assembly according claim as well as a. brake pad assembly accordi, to claim. 9, as well as a brake caliper according to claim 10.

[0022]. Some advantageous embodiments are the ect of the dependent claims, [0023]. According to an aspect of 1-he invention, the suggested solution na intalns very WO if not miproveo.traking efficiency, e,g., the efficiency is strongly Improved by virtue of the absence of frictional contact between the pad return spring and the aclp holding spring during normal operation, and where the pad return spring is shaped so that should a frictional contact occur be. Lwet the pad return spring and the pad-holding spring, the surface of the return spring which contacts the pad---hoiding spring is highly small compared to the known solutions [0024]. The analysis of this solution shower_ that the suggested solution allows limiting the contact area between fhp return spring and the pad-holding sprig due to any t anqential slid ing of the pad return spring on a disc-side surface of the brake pad, to a fraction of a cross-section of the r&d return spring wire, on the one hand rec c rig any genexatable friction force, and on the other hand avoiding a spring wire portion. from becoming stuck between the brake pad and the pad-holding spring, or even beLnq ram, ed from the craiKe pad, thus losi o the connection, [0025]. .Add'fic aaly, fIe suggested solutions allow increasmng the service life of the pad--holding spring and pad return soring assembly compa.red to known solutions, and dxasticaliv reducing the maintenance interventions.

[0026]. The ana:vsis of this solution showed that the suggested solution allows obtaining a higher residual torque reduction between the pad and brake disc than the solutions of the pxior art, thus reduction in the events of uneven brake pad wear and in particular a reduction in the maintenance events.

[0027]. Drawings [0028]. Further features and advantages of the spring assembly,-the pad. assembly, and the le caliper assgmlolv will become appa -Grit from the following description of preferred embodiments thereof, Given byway of non-limiting indication, with reference to the accompanying drawings, in which: [0029]. -Figure 1 shows an axonometric view of a brake caliper according to the present invention, eormorising a caliper body, least one brake pad, and at least one pad-holdiitg op-ring and pad return spring assembly according to the present invention, which is-.

connected to the caliber body and the at: least one brake pad; [0030]. -Figure 2 shows an axonomEtiic view of a pad assembly comprising a pad-holding spring and pad return spring assembly according to the present Invention, connected to a brake which a brake disc facing the brake pad is d-iagrammat-ica:ly shown; 10031]. -Figure 3 shows a. front view of the pad assembly in Figure 2, where there is shown a pad support plate on the side opposite to the brake disc,, [0032]. -Figure 4 shows a front view, diametrically opposjte to the fronf view in Figure 4, of the pad assembly in Figure 2, where there is shown the pad friction material and the brake disc side sur*face of the plate, where t her er,c3, shown the ccawdirm portion in contact with the brake disc side surface of the plate, at the ear of the pad, in which the coupling portion is bent so as to prevent an Involuntary disconnection of the pad return spring from the brake pad and so that the friction contact surface between the pad return sprinu and the pad return spring Is reduced in the case of sliding. in the tangential or circumferential direction of the coupling portion In the direction of the pad-holding. spring; [0033]. -Figure 5 shows an axonometric view or Lhe bad-holding.

spring and pad return spring assembly according to the present invention; [0034]. -Figure 6 shows a front view, perpendicular to the axial direction, of the pad-holding spring and pad. return spring assembly in Figure 5 on the brake disc side, where in the foneround there is shown the end portion of-the pad return. spring wire portion ha4211.1g a bent portibn in a. plane perpebdicular to the axial direction; [0035]. -Figure 7 shows a side view, perpendicular to the tangent id. direction, of the pad-holding spring and pad. retum spring assembly in Figure 5; [0036]. Figure 8 shows an axonometric view of a furMileh embodiment of a pad-holding spring and pad retbrn spring assembly according to the present invention, where there are shown two pad-holding spring and pad return spring assemblies fram Figure 5, which are mutually specular with respect to a central plane perpendicular to the axial direction and connected by a. bridge-like portion; [0037]. -Figures 9 and. 10 show an axonometimc view of -connecting prtlon of the pad return spring wire portion connected to the pad-holding spring by riveting and/or clamping; [0038]. -Figures 11 and 12 show an axonometric of a connecting portion of the pad return spring wire portion connected to the pad-holding spring with an opposite disc side end portion of the S-tbeht pad return spring so as to be inserted Into a hole of the pad-holding spring, and the S-bent portion in contact with opposite surfaces of a wall of the pan-holding spring and retained by a coupling element; [0039]. -Figure 13 shows an axhnometric view of the pad-holding spring and pad return spring assembly according to the present invention, in which the pad return 5,',pincs comprises at least one wire portion comprising a winding being coaxial to the circumferential diiecLion, and in which the end portion of the wire portion forms at least one bend in a plane perpendicular to the ID1122 2-e-pq 04 paanbT4uo'D Si E buTads uan40a pF2c1 pfes 'Itvool D-9 u01-74neJ114 IpTquaaajmncaT0 pup uorq03:17Tp TPTPrra 07474 uT TOT P-ed aNniq PTe2 seTq cy:1 10dTTuo 042X egg 40 661 74Doci, -cedT1t= egg Put? OOT apd-rye'D 045?-72 °UPI JO COT P-ed eNeaci P JP ITT -1120 buTPTub DUO 1PPOT TIP ue0m40g 07, :-Ju 0:4 u:Daufruj:uo:D sr 4 buHds bujpToq-pud '[9P00] -pagssuuos AT0A-y4eapdo u0111 pup 940npoad B49 1114 4U91944 [-P Jo 91412111,4 5u-rads 111n7191 pod 9110 -12e9.1 4e LuTad2 LuTpTog-ppd suc 4=:P0T qe sogTidifion T ATqWePPP PT13 '[5P00] ieunpm 01 burippeJ.qs e 151 pepeTd eq ues QQJJec.41e2 eNeaq e1)4 Jo 601 Apoq:nisdTTE,c,U TioTqm uo '7.0T 2,8TP 0=112111 72 40 sT= u0T-4ol P 07 T9TTTPd ST \I--dOrljalP [PJZP PIPS 'IJUDWIPOqUe UP on. buTpaoccy -Eppoo: uoT490LITP InTP'=3 preE7 Fre 71-v LIGT490iTp TeTxu pTps 1)404 JeTnGioued-id 19.-4) 1JxD.[T109.11p TeTquebueg JO TPTIUBJ9JUIWOJT2 Apoq:JadTips p ao/pue pd aNpJa, e 04 poidnos uoTTrpuoG 151222129i P PT 2T ----122pM. p9c1,H7,s9p 21 I AIqua2Ee 9.44 iPDTJTGeds esTm7BU4o snaTun funTgdTrinaP buTmoTT07-DTTn -papii\oTd Jed:rips aNuiq u JOJ I ATwassp buTads' pod pup buTpiou-Tyed e eque-alTpoo Tpieueb p 04 buipioccv "[TP00] smamLpoqw9 p9JA9J9Jd 9509 40 UOPICLAS29C Foroo] -uoln.cairp LE-J,j2CP 12014D9a.Tp 12:rxe pTec, 04 aeTuDTpuao.a&ca 1204 411p ucT-49ipiTp Tie 12012420-T Al.qmp:?s-e -[coo]

TIT Cl

pad 101_ in the axial direction. A-A away from a brake disc 102.

[0048]. Said pad-holding spring 2 has a main extension in the radial R-R and circumferential C-C directions.

[0049]. Said pad-holding. spring 2 comprises at least one C-shaped.

section 4. Said C--shaped section. 4 comprises a centkal portion 5, an upper portion 5, and a. lower portion 7. The central portion 5 extends at least in a radial direction R-R, mainly along said radial. direction R-R. The upper portion. 6 and the lower portion 7 extend i:ri a cantilevered manner at least partially in the circumferential direction C-C from said central portion 5, extending from two radially opposite ends of the central portion 5. According to an embodiment, the central portion 5 extends at least in the radial direction R-R and the axial direction A--A. According to an embodiment, the upper portion 6 and the lower portion 7 also extend in the axial direction A-A, According to an effbodimenty the upper portion 6 and the lower portion 7 extend in a cantilevered manner from two radially opposite ends of the central portion 5 along a longitudinal direction comprising the cArciimferential direction. C-C and the radial direction R-R.

[0050]. Said C--shaped section 4 is adapted to be inserted into a recess 106 of said caliper body 109 and is aMapted to accmmmodate said guiding ear 111, [0051]. Said pad return. spring. 3 comprises an anchoring portion. 8 operatively connected to said C--shaped section 4, a coupling. portion 25 10 configured to couple said brake pad. 103, and a linking arm 9 operatively connected to said anchor.Lnq portion 8 and said coupling portion 10. Said coupling portion 10 is elastically movable with respect to said anchoring portion H in the axial direction between a retrac eci resting position and at least one advanced. PC) sition, tolards said disc 102, and vice [0052]. According to an embodiment said anchoring Portion extends from said C-----taped section 4 in the axial diacection A.-A in a ft ec.tion, opposite to said disc. 102.

[0053]. According to an embodinent, said linking arm 9 extends 10 from said anchoring portion 8 along a lorLgltudrn.ai. arm direction oriented in an axial direction A-A mainly in a second direction coacurdadaf with said disc 102, opposite to said first (traction [0054]. According 2d an embodiment, said coupling portion 10 is elastically movable in an axial direction.-,7-'2--A between. at least one advanced position towards said disc 102, pro Lraoted adong said second direction, and a retracted resting position in the opposite 32- [0055]. Said pad returnspring 3 is made f a at least one wire.

[0056]. Said linking arm 9 comprises an arm end portion 16 either directly or indirectly connected to said coupling portion 8.

[0057]. Said arm end portion 16 is arranged at a first distance 1l1 along said circumferential direction (22-C with respect to said central portion 5 or a radial extension thereof and/or an axial. extension thereof.

[0058] .Advantageous 2\ said seconci distance D2 is less than. said first distanc.e in the case of circumferential cr antial sliLdIng of the coal ing portion 10 with respect Inc the brake pad 1017 towards said central portion 5, during the assembly and/or dun inc very aggressive wear conditions of the friction material, said first 22 thus interferes with said central portion 5 first preventing said arm end. port rca. 16 from contacting said al poixion 5, thus prbver ing the coupling portion 10 from uncoupli from the brake 103 on the one hand, and limitinci any friction forces generated between the pad return spring 3 and the central portion 5 of the pad-holding spring 2 in the case of sliding 10 contact, between the pad-holding spring 2 md the pad return spring.

[0059]. According toan m eboMiment, said first stretch 22.comprises the portion of said coupling portion 10 closest to the central wall 5 or Inc an extension thereof in the radial and/or axial lb direct n, the ad-holding spring 2. in the circnnn i direction.

[0060]. Accor ing to an embodimen C, said firsL stretch 22 is the po iton of said coupl1ng portion 10 and said king arm 9 closest to the centraX wall 5, or to an extens 1.On tnereolT in the radial and/or axial direction., of the h 'ding spring 2 in the cn.rcu.mferr-nn.ti.al direction.

[0061]. According to an embodiment, said first stretch 22 has a His a -ree spring end 23. According to an emir)/ 1MaE, said free spring end 23 faces said central portion 5. According embodiment, said free spring end 23 is defined by a surface of section of the wire of the pad return spring 3 According to embodiment, the free spring end 23 has a smaller surface than the surface of a circle having the diameter of nrLe ad ret r wire as a diameter. itccoro.ang to an embodinnt, said free spring end 23 is configured interfere with said central portion P Thereby is DOS -it:pie tr) limit the contact surface between the pad return inc 3 and the central portion 5 in the case of accidental raferential sliding of the coupling portion 10.

[0062]. According to an embodiment, said coupling portion 10 comprises a. second stretch 24. kccording to an embodiment, said second stretch 24 and said first stretch 22 are connected, forming a coupllng portion ahgle. According to an. embodiment, said coupling portion angle is an acute angle facing the central portion 5. According to an. embodiment, said second. stretch 24 and said firs stretch are c,onnect-1 formlnx a concav portion where said concave portion faces the central portion 5.

[0063]. According to an embodhrlent, the second stretch 24 and the fir stretch 22 are arranged or lie on the same coubling portion plane, in which said coupling portion plane is perpenaicuiar to said axial direction A--A. According to an embodlment, the second stretch 24 and the first stretch 22 form a V-bent portion_ The provisioJ.l of the first stretch 72 and the second stretch 24 allows obtaining cogpling par Li on 10 capable of reois+-i.0 the st PssPs of the b pad in a highly reliable manner even under conditions of very advanced wear of thp traction ircater= [0064]. According to an embodiment, said first stretch 22. is a straight wire stretch, said second stretch 24 is a straight wire st etch, where said second s tretch.. 24 and said first stretch 22 are connectea DV a third stretch 25, where sici third stretch 25 is cLved.Accordlnq to an emb, dimgnt said second stretch 24 is inclined sri the conning portion plane by a second. stretch between 0 and 45 dearees with -P respect to said adial directich7P, preferably between 15 and 30 degrees.

[0065]. According to an embodiment said spring return bad 3 between said coupling 1 10 and said anchoring portion. 8 is bent so as to elastically return the coupling portion in the direction of said retracted resting portion_ According to ait. embodiment, the coupling portion is constantly elastically returned in the direction of said retracted resting portion_ [0066]. According to an emboOment, said I lnkl nq no 9 dir connects the anchoring. portion 8 to the coubling portion 10 bent so that it constahtly elastiuilly return the coupling portion in the direction of said retracted. resti= poiLion. 7c:cord inq to an EtillboditflEtllt, 5 JO linking arm 9 is bent in a plane comprising the radial direction and the axial direction so as to elastically return the 000.niincf portion by bendir in the direction of said. retracted resting portion.

[0067]. AcciirWng to an embodiment, advantageously, said pad return spring 3 comprises at least one winding portion 17 connecting said linking airm 9 to said acchorHnx portion S Said at least one winding portion. 17 comprises said at least one wire spira I i.y wound about a winding axis A. Said winding axis A is oriented so as to constantly elastically bias Ss.: d coupling portion IC towards said acted resting position along ial direction A-A, avoiding contacting said no rt.ison 11 of said brake pad 103 Accordi to an embodiment, the winding a subs t antior I parallel to said axial direction Pc--A Accord to an embodiment, the windi A. is incide.nt with respect to the axial direction A-A. avoiding:being perpendicular to the axial direction [0068]. Thereby possible ILIJD IiIILLt the axial extension of the pad return spring 3 by virtue of the winding po tion 17 which allows storing elastic "energy by bending the pad return spring into p1,-,fies incident and/or substantially percendicular to the axial direction, , Advantageously, it is possible to avoid bends from being. 15 created on the at least one wire in planes comprising the axi.al direction, avoidiril, acting with portions of the pad reLui_n spring under bending for e.l ast.cal l.y awih.g the coupling porti [0069]. According to an emdmodHent, saidndir 7.17 per comprises a plurality of coils 31, 32 wound about said winning axis A. According to an embodiment, the plurality of coils 31, 32 asticaily deforms by torsion, elastically biasing said coupl.ing portion 10 towards-said retracted resting COSH ion According to embodiment, the bad return spring 3 is bent seas to prevent-elast L deformation by bending in the axial direction k-P in the linking arm 9 and/or in the coupling port-on 10 arid/or in the winding portion 17, during normal operation.

[0070]. According to an embodiment, said plurality of coils 31, 32 comprises at least a fins:-0011 31 and a second coil 32. According to an embodiment, each coil 31, 32 substantially has the same outer diameter. According loan. embodiment, at least one coil of the plurality of coils 31, 32 has an outer dianeter that is smaller and/or larger than the outer diameter of at leas,t one other coil cf the plurality of coils 31, 32. According to an embodiment, said plurality of coils 31, 32 are concentric. According to an embodiment, the first coil 31 is misaligned with respect to the second coil 32. According to an embodiment, said plurality of coils 32 form a cr1indrical or conical helical sprjng portion.

[0071]. According to an embodiment, said at least one wire has a wire diameter. According to an embodiment, said winding portion 12/ has a winding pitch between. said wire diameter and 4/3 of the wire diameter. According to an embodiment, said winding pitch is defined as the distance along the dirbction of the winding axis A be the center of at least two adjacent coils.

[0072]. According to an embodiment, said winding portion 17 defines a first axial pad return spring envelope Al. Said linking arm 9 and said coupling portion. 8 define a second axial pad return spring envelope A2. Said first axial pad return spring envelope Al is less than. the second axial pad return spring envelope A2.

[0073]. According to an embodiment, said winding portion 17 25 defines a first radial pad retnru spring envelope pi, said coup' defines a second radia p ad rn spring envelope R2. The radial pad return spring envelope RI is smaller than the second pad return spring envelope R2.

[0074]. :According embo said winding portion 17 is bent under winWng with respect to said winding axis A accpfliing to a winding direction, in which sa.d. coupij.ng portion 10 is pent at least partially in a direr-Hon opposite to the winding-direction, [0075] By virtue of the prov sion of the winding portion 17, it is possible to significantly reduce the axial envelope of assembly 1, by reducing, or even elircina t irto, the probability of pia at i cally deforming the turn spring wire during the assembly operations of assembly 1 to the brake pad 103 and the caliper body 109, By virtue of the bending geometry of the pad return spring as a spiral winding of the wire about the winding axis A, it is possible to 15 provide an elas tic energy s oIage portion wh oh lasts overtime and is highly resistant to impa in the cirrcunlerent.ral or radial during the; assembly [0076]. By ^,7-1 of the provision the winding portion 17 allows oft_ small envelope rn the axial direct:., A-A of tne pad return spring 3, while maintat istance, high elastic re turn force applicable the pad, and. high reliability over time, possible to mount the assembly 1 on several geometries of existing. calipers. Addltionally, by virtue of the small envelope In the axial direction Amr,_ of the pad return spring 3, ic is possible to provide new calipers having small dimensions or introdu.oe other lE elements by virtue, of the small axial envelope.

[0077]. By virtue of the provision of the winding portion 17, it is possible to reduce the axial rIgid if of the pad return apr Lam-with respect to pad return springs including elastic return arms to benos and ox._rnsion. in. . "[prising th4a axial. direction.

Thereby, on the one hand, it is possiole to support and elastically return I-he pad in a highly reliable manner even under conchlMons ct extreme wear of the friction mated 1 and other hand it is possible to obtain reliable results in a broader range of g2o.2 10 tolerances as compared to the known. solution.

[0078]. '.13,2 virtue of the provision of the winding portion i is possible to increase the longitudlnal lehoth of the wire of the pad return spring 3 without increasing the axial envelope or keeping the axi all, envelope very low as compared to the:mown solution. By virtue of tite provision of the winding portion 17, t is pos sl.ble to bend the wire spring about a winding. axis which can be oriented or notin the same din. tion as the elastic return force to be applied to the pad. By virtue of the provision of the winding portion 17, the return forces. rroplied to the pad are due rio the torsional deformations of the coils of the winding portion, avoiding the generation of elastic forces by benninu in t axial direction.

[0079]. According to-an embodiment, said anchoring-portion 8.

f.1 ast a first strai ght. stretch 19, whi... extehds away from the brake disc 102, where said first straight stretch 19 is parallel to the axial direction A-A. Accord in b an embodiment, sal(' anbroring portion 8 has at least a first curved stretch 18 connecting said winding portion 17 to said first straight stretch 19 to arrange the winding axis A of the wIndifig-portion 17 parallel. or incident and/or perpendicular to the axial direction A-A. According to an embodiment, the winding portion 17 extends in a helcal manner in the direction of said brake disc 102. According to an embodiment the first curved,h_letth is bent at a right angle.

[0080]. :According to an embodiment., said linking arm 9 is substantially straight and parallel to said axial direction A-A.

Accord no: to an. embodiment, during normal operation of the assemil said linking arm 9 avoids elastically biasing the coupling portion 10 in the axial direction, -For example by bending.

[0081]. According to an embodiment, said linking arm 9 is connected to said winding portion 17 by means of a first curved connection 33 that forms a right angle with said winding portion in a Plane comprising at least said axial direction A-A so as to arrange said linking arm 9 parallel to said axial direction [0082]. According to an embodiment, said second stretch 24 is connected to said arm end portion 16 and/or said linking arm 9 by means of a second curved connection 24, substantially forming right angle between said linking arm. 9 anx1 said coupling portion 10L [0083]. According to an embodiment, said anchoring-portion 0 has a second straighM stretch 21 connected to said first curved stretch 10. According to an embodiment, said anchoring portion 0 has a 25 second curved stretch 20 from which the winding portion 17 extends, where the second curved stretch 20 and the second straight stretch. 21 lie at least partially on a plane perpendicular to the axial direction A--A.

[0084]. According to an embodiment, said pad-holding spring 2 comprises a couplind wail 13, where said in:boring portion 8 of said pad return spriiig 3 is anchored to said. coupling wall 13 of said pad-hoiding aprinu 2.

[0085]. According to an embodiment, said anchoring portion 8 is rolingThd at least to one surface said coupling wall 13 facing the concavity deliimited by the C--shamed section 4 in the radial. direction RR.

[0086]. According to an embodiment, said pad-holding spring 2 comprises a coupling element 14 connected to said coupling wall 13. According to an embodiment, said coupling element 14 comprises Iea:jsta pair of coupling tabs 15 configured. to Lighten. at least one portion of said anchoring portion 8. According to an embodiment, the pair of coupling tabs 15 is tightened to the first straight stretch 19 of the anchoring portdon 8. According to an embodiment, said anchoring portion 8 of said pad return spring 3 is riveted or welded or coupled by interference to said coupling wall 13.

[0087]. According to an embodiment, said anchoring portion 8 comprises a third straight stretch 34 connected to said first straight stretch 19 by means of a thlrd curved stretch 35 so as to form an S--bent anchoring portion end -pertion. According to an embodiment, the first straight stretch 19 is In contact with a lower surface of the coupling wall 13 facing the opposite side with respect to the enclosed portion of the C-shaped section 4. According to an embodiment, the coupi. lug wall 11 has a through be,1,-, in which least one Portion of the anchoring portion 8 is inserted. According to an ambodtment, the third cutved stretch 35 is I u.s s.r Led. ilTto the hole of the coupling wall, and th.e third straight stretdh S contact with an upper su- of line couPling wall 1 facing the enclosed portion of the C-shaped ion opposite-to said upper surface of the coupling wall 13 so as to connect the pad return spring 2 to the pad--holding spring. 3, According to an embodiment, said anchoring portion 8 comprises a third st.ra.ght stretch 34 connected to said fl-,1-st straight stretch by means nf a third chrved stretch so as to form. an -bent anchoring portion. end portion 1.5[0088]. According to an e:ubocii.rten. sad pd-holding spring comprises a first cantilevered 'portion ii operatively connected to said lower port ion / extending in a cantilevered manner in an ax al directio A-7\ in the airection opposite to said brake where ad-holddng spring 2 comprises a second cartilevert portion 12 operatively connected to said first cantilevered portion 11 extending in a cantilevered manner in a cin=mierential dl rect.ion C--C, where said anchoring portion 8 of said pad-holding spring 2 is fl'ed to saia second ca.ntilever-d portion 12, where said second.

cantilevered portion 12 comprises said coupling wall 13.

[0089]. According to an embodiment, said assembly I. comprises two pad-holding springs 2, two pad return. springs. 3, and a. bridae-like portion 36 connecting said two pad-holding springs 2.

[0090]. According' to an embodiment, said pad return spring 3 is made with two parallel wires placed side-by-side.

[0091]. _According to an embodiment, said pad-holding spring 2 comprises an L-shaped section 26 seamlessly operatively connected to said C-shaped section 4. According Lp an embodiment, said P--shaped section. 26 comprises a first support portion 27 operatively connected perpendicularly to a second support portion 28. According I0 to an embodiment, the first. support portion. 27 extends perpendicularly from said upper portion 6 of said C-shaped section 4 so as to obtain, with said upper portion. 6 and said second support portion 20, a U-shaped section having concavity opposite to said C--shaped section 4. According to an embodiment, the central portion 5 of said C-shaped section. 4, comprises a first retaining element 29 which extends in a cantilevered manner in a circumferential direction C-C otside the ioncavity of odi,..1 C-shaped. section 4. According to an embodiment, said I--shaped section 26 comprises an opening between said first support portion 27 and said second support portion 28, and said first support portion 27 comprises a second retaining element 30 which extends in a. cantilevered manner in a circumferential direction C-C into said opening. According to an embodiment, said first support portion 27 comprises a pair of retaining elements which project from opposite-edges in a circumferential direction C-C into said. L-shaped. section 26.

[0092]. In an embobr ent, the brake pad 103 is an outer side brake pad or an inner side brake pad, where the outer side brake pad is further spaced apart from the vehicle as cumpared to the =Hid& brake ca an embodiment, the 'inner side brake Dad is adapted be biased directly by thrust means or pistons of the brake caliper, and the):..ter. side brake. pad is adapted. to be biased 1-1df.r.ec,1 r1,7 said thrust means or rJ.stions of the brake caliper by means of the floating element 110 of the caliper body 109. In embodiment, each pad return spring 3 connected an adapted to be connected to the outer side brake pad defines an cute side return load. in an embodiment, each pad return 3 connected and/or adapted to be connected to the inner side brake bad defines an inner side return load. in an embodiment, the inner side return load is equal to the outer side return load. In a brake caliper of the floating. type which suppor of brake pads rn1flor1sing inner side brake pad and the outer side brake pad, once the braKi ac is complete' the pad return 5,1P-ffirics 3 atLing on the inr3 e brake pad thus work in a symmetric manner and with the same air as the pad return. springs 3 acting the outer brake pad. In an embodiment, the ',inner side return load is lower than the outer side return load. in a. brake caliper of the floating type which supports the pair af brake pads.RrHsing the inner side brake a.d and the outer side brake pad, once the bra i action is completed, the pad return on the inner aid-brake bad thus work in an asymmetric manner with. respect to the ad return springs 3 acting on the outer side brake pad. By virtue of the provision of the outer side return load increased as compared to the side return load, in addition to al dv.,71:ng. the brake pads to move --.y from the brake disc., a return forcb is applied by the pad retbrn springs 3 to the flo at mc: element 110 of tho caliper body in the resting -sitior. thereof by moving away f.npl, the vehicle, helping I tto be partially P. -cont ed. with re iect to the ake disc and ensuring a =caplets detachment of the bra e pans with respect to the disc.

[0093]. The present invention also relates to brake pad assembly for a brake caliper 100. The brake pad asseffhly comprises at least one brake pad 103 and at least one pad-holding sring and pad return. ag assembly 1 according to any one of the embodiments described above.

[0094]. Said pad-)l(111.-19 spring. and.c*-^ return sri ing assembly 1 is connectable to said brake pad 103. Said brake pad 103 catprises friction. material 105 and a support plate 104 which supports said frction mater-H1 105. Said support plate 104 cmmpri ses at least one guiding -.r Ill which protrudes in the circurmaerential direction C--C. Said C-shaped section 4!aid pad-holding spring 2 con.-gured to accommodate said at least one giiiding ear 111 so as to bias said pad 103 in i circumferential direction C-C and. . a radial direction R-R. Said no portion. 10 of sand pad return spring is configured to couple said guiding ear Ill to bias said pad 103 s 9 directirn away from a brake disc 102 by moarb of said windi Z 5 portion 17. According to an eMbodiment, said winding portion 17 is axially spaced apart from said coupling portion 10 of at least said linking arm. 9. According to an embrritment, said winding portion lll is partially external with respect to the footprint of the support plate 104. According to an embodiment, said windina portion 17 is partially external with respect to the footprint of said guiding ear. lii_ In this description.., footprint means the profile of an element with respect to a plane perpendicular to the axial direction A-A. According to an embodiment, said winding portion 17 avoids directly contacting said support plate 104, [0095]. According to an embodiment, said brake pad 103 comprises an ear side edge 112 which laterally delimits said at least one guiding ear 11 in the circumferential direction C-C and radial direction R-R. According to an embodiment, said brake pad 103 comprises a rear ear guiding surface 713 facing the opposite side with respect to said friction material 105, and a front first-ear surface 114 facing the same side as said frtction m.aterial. 105.

[0096]. According to an Embodiment, said ear side edge 112 is insertable into said C-shaped section 4. According to an. embodiment, said coupling portion 10 is couplable to said front first-ear surface 114 so as to bias said pad 103 in the axial direction. A--..P, constantly in a direction opposite to said friction material 105.

[0097]. According to an embodiment, said ear side edge 112 defines at least one recess 115 delimited radially by a radial edge portion 116 ma] fly extending along said -radial direction. R-R and by a crrcurctterentcai. edce portion 117 mainly extending along said circumferential direction C-C. According to an embodiment, said edue port ion 116 and sold clrcu ferential edge:Doti-ion 11.7 are connected in a stepped mannr, where sa Li arm end portion 16faces said recess 115 in the radial di rectic-n P.-A facing saici o Ti. r oun f e rent a i edge117 and in the circumferential direction C-C facinfl said fatiai edge 116 wi. shout contacting them _ 7Acco ding to an embodiment said winning portion 17 partially es said recess 115 According to an embodiment, said coupling portion 10 is in co.

with said front ear surface 114, and/or with an ear corner 107 defined by the intersection of said front ear surface 114 and said circumferential edge 117 delimHtjng said recess 115.

[0098]. The present ntion also relates to a brake cal _ 100 comprising at least pne pad assembly accordf -g any one of the embodim.ents described a OVe.

[0099]. The brake caliper 100 comprises a calicer body 109 connectable to a vehr ole and adapted to be arranged straddling a brake disc. 1 02, where said caliper body 109 cc.npri sec at least one brake pad housing pocket, where said housing pocket comri.ses at least one recess 10. Said pad-holding spring 2 is interposed at least between said guiding ear 111 and said recess 106. Said coupling portion 10 of said pad return spring 3 is coupled to said guiding ear 111 to bias it in a direction away from said. brake disc 102.

[00100]. According to an embodiment, said caliper body 109 comprises a support 101 fixedly connectable to said vehicle, where said support 101 comprises said at least one brake pad housing pocket.

[00101], According to an embodiment, said caliper body 109 comprises a floating element 110 connected in a floating manner to said support 101, said floating element being configured to be arranged straddling sait brake disc. 102 and to directly cx indirectly bias, by means of thrust means, said brake pad 103 along said axial direction It--A towards said brake disc. 102 between at least one pad resting position and one pad braking nositon.

[00102]. According to an embodiment, said brake disc. 102 comprises a disc axis, where said axial direction A-A is parallel to said disc axis.

[00103]. According to an embodiment, said caliper body 109 15 comprises a support protuberance 108, where said L-shaped section 26 is coupled to said support protuberance 108, and/or where said support 101 comprises said. support protuberance 108.

LIST OF REFERENCE SIGNS

Pad-holding spring and pad return. spring assembly 2 pad-noldillg spring 3 pad. return spring 4 5-shaped section 5 central portion.

6 upper portion 7 lower portion anchoring portion 9 linlinq arm 10 coupling portion first cantilevered portion 12 second cantilevered portion.

coupling wall 1.4 coupling element 10 coupling tabs 16 arm end portion.

17 winding. portion.

18 first curved stretch 19 first straight stretch 20 second curved stretch 21 second. straight,biebch 22 first stretch 23 free spring end 24 second. stretch 25 third stretch 26 L-shaped section 27 first support -oortion 28 second support portion 29 first retaining element 30 second retaining element 31 first coil 32 second coil 33 rct curved connection 34 second. curved connection third straighL, stretch 36 bridge-like portion brake caliper 101 support 102 brake disc 103 brake pad 104 support Ldate friction material 106 recess 107 ear corner 108 au-apart protuberance 109 caliper body floating element 111 guiding ear 112 ear side edge 113 rear ear surface 114 front Par surface ear recess 116 radial edge portion 117 circumferential edge portion axial direction R-R radial direction C-C circumferential or tangential direction

Claims

CLAIMSic pad-holding spring and pad return spring asap:71)1y for brake caliper (100), said. brake caliper (100) comprising a caliper boag (109) adapts( to be arranged straddling a disc brake (102), wherein said assembly (L) defines an axial direction (P.-.A), a iadial direction (R-a) perpendicular to said axial direction (1,..-A) and a circumferential or tangential direction (C-C) perpendicular to bo said axial direction. ;A-Ai and said radial direction (R-R), said assembly cmmprising: -at least one pad-holding spring (2) configured to be arranged.between at least one guiding e of a brake cad (103) housed.in sad caliper Ho and said caliper. body (109) so as to bias said brake pad (103) in radial direction (P.----R) and circamierenLial dirPction (C-C), and -a pad return spring (3) configure_ to bias said brake pad (103) i the axial direction (A-A) away from a brake disc (102), wherein said pad-holdHng ring and said pad return spring are made as separate pieces and are operatively connected, wherein said pad-holdi spring has a prevailing. extension in radial (R-R) and circumjerential (C-C) directions and comprises at least: -a. C--shaped section (4) comprising a central portion (5) which extends at least radial Potion from which an upper portion (6) and a lower owe, pertion extend from its radi opposite ends, wherein said upper portion h'. and said lower portion (7) develop at least partially in a circumferential direction (C-C) away from said central portion wherein said C-shaped section (4) is adapted to be inserted in a recess (105) of said caliper (109) and is adapted:o accommodate said guldilng ear 1), wherein said pad return spring comprises: -an anchoring portion (8) operaii-,,ely connected to said C.-shaped section coupling po ion. (10) cprid.qur-d to couple said brah (103), and -a linking arm operatively connected to said anchor: rig portion (8) and to said coupling portion (10), wherein said coupli -portion (10) is elastically movable relative to said anchoring portion in the axial direction between a retracted resting posi -on and at icc one advanced posi Lion, towards said disc (102), vice versa,.wherein said turn sprang (3) is made from at least one wire, wherein said Thrn(nng arm (9) comprises an arm. end portion (16) connected to said coupling portion. (6) wherei said arm end portion (16) is arranged. at a first distance (D1) along said circumferential direction (C-r) re ative to said central portion (5) or a radial extension thereof, wherein conphing po ion (10) comprises E first stretch. (22 which is arranged at a second distance along said. circumferential direction (C-C) from said central portion wherein said second distance less than said first distance (D1).74. pad-holding spring and pad retnrrL spring assembly (1) according to claim i, wherein said first stretch (22) has a spring-free end (23), wherein said spring free end (23) is adapted to face central portion (5), wherein said spring free end. (23) is dfinea by a surface equal to a cross section of said at least one wire, 3. it pad-horning spring and pad return spring assembly (1) according to any one of the preceding claims, wherein. said. coupling spring comprises, a second stretch (24), wherein said second stretch (24) and said first stretch (22) are 10 connected forming a coupling portion arile and/or forming a concave portion in which said concave portion faces the central portion (5), 4. it pad-horning spring and pad return spring assembly (1) accondincc to claim 3, wherein the second. stretch (24) and the first stretch (22) are arranged or He on the same coupling portion plane, wherein said. coupling portion plane is perpendicular to said axial direction (A--A.); and/or wherein said cc4ipling portion angle is an acute angle facing tine 20 central port-ion (5), 5_ A pad-holding spring and pad return spring assembly. (1) according to claim 3 or 4, wherein said first stretch (22) is a straight wire stretch, wherein said second stretch. (24) is a. straight wire stretch, wherein said second stretch (24) and said first stretch. (22) are connected by a third.stretch (25), wherein said third stretch (25) is curved; and/or wherein said second stretch (24) is connected to said arm end portion (16), substantially forming a right angle, wherein said second stretch (24) Is in.-lined in the coupling plane portion by a second stretch angle comprised between. 0 and 45 degrees relative to said. radial. direction. (R-R), preferably between 15 and 30 degrees.6. A pad-holding spring and pad return spring assembly. (1) according any one of the preceding claims, wherein said pad return spring (3) comprises at least one winding portion (17) connecting said linking arm (9.) to said anchoring portion (Efl, wherein. said. at least one winding portion (17) comprises said. at least one wire, wound as a spiral about a winding axis 1211.2 so as to constantly and elastically bias said coupling portion. (10) at least along said axial direction (A-A), towards said retracted resting position, avoiding. The contact of said winding portion (17) with said brake pad (1011) andlor said pad--holding spring (2), 7 k pad-holding spring and pad return spring assembly (1) according LO claim 6, wherein said winding portion (17) comprises a plurality of coils (31, 32) wound around said winding axis (A), wherein the plurality 25 of coils (31, 32) elastically deforms by torsion thus elastically biasing said coupling portion (10) towards sald retracted resting position, preventing elastic deformation by bending in the axial direction (A-A) in the linking arm (9) and/or in the couplinci portion. (10); and/or wherein said winding axis is oriented. substantially parallel to the axial direction (A-A) or is incident and/or perpenAdcular to the axial direciion. (A-A) or a direction. palailel to it.B. A cad-holding spring and pad return spring assembly. (1) according to claim.wherein said plurality of coils (31, 32) comprises at least one first coil (31) and one second coil (32), and/or said plurality of coils (31, 32) are concentric forming a cydindrical or cervical helical portion of the spring, and/or wherein said at least crew ire has a. wdre diameter, wherein said winding portion ( S7) has a winding pitch. coavrised between said wire diameter and 4/3 of thr, wire diameter, wherein said winding pitch is defined as the distance along the winding axis (A) between the centers of at least two adjacent. coils.9. A brake pad assembly for a brake caliper (100), comprising at least one brake can (103) and at least one pad-holding spring and pad return spring assembly (1) according to any one of the preceding claims, wherein said pad-holding spring and pad return stdrinof assembly (1) is connectable to said brake Pad (103), wherein said brake pad (103) comprises friction material. (105) and a support plate (104) supporting said friction material (105), wherein said support plate (104) comprises at t one guiding ear (11 protruding lateral In a circumferential direction (C-C), wherein said C-shaped section (4) of said -bolding spring (2) is configured to accommodate said guiding ear (111) so as to bias said pad (103) in a ciriawmiAarential direction. (C-C) and radial direction (R.-R), -Wherein said coupling portion of said pad return sprang (3) is configured to engage said quidlng ear (111) so as to bias said pad (103) in a direction away from a brake disc (102) hr means of said winding portion (17) distanced by at least said linking arm (9) from said. coupling portion (10), arid/or by preventing the 9ncoupling of said cocipijng portion (10) from said brake pad (103).10, A brake cal'iper (10e) comprising -a. caliper. body (109) connectable to a vebicle and adapted. to be arranged straddling a brake ddsc 102), ;therein said caliber body (109) comprises at least one brake pad housing pocket, wherein said housing pocket comprises at least one recess 106), -a. pad assembJv according to ci aim 9, wherein said pad -hbl di.ng spring interposed at least be tweerL sal_ guiding ear (111) and said. recess 106), wherein said coupling portion. (10) of said pad return, spring coupled with said guiding car (111) 'biasit in a direction away from said brake disc (102).