Patent Description:
Vehicle brakes are a critical system that not only reduce car speed but prevent dangerous collisions from occurring and are a design concern for automotive engineers. Drivers are demanding even safer, properly working braking systems, to provide effective vehicle speed reduction, with another important factor, emission of low or zero noise. Brake pads, a major component in braking systems, are designed to create friction against wheel discs to reduce their speed when engaged to contact the disc by hydraulic piston. However, this friction generates unwanted heat energy, vibrations and high pitched noise. Brake pads are engineered to withstand the heat resistance and remain their braking performance but an element called break pad shim is needed to further absorb this generated heat and protect the sensible elements of car breaking system.

A brake pad shim is assembled to a brake pad; it keeps the brake pad and wheel disc perfectly aligned also reducing its vibration, which effectively is perceived as a high pitched piercing noise by a human ear. Critically, brake pad shims by absorbing the vibration reduce noise pollution from vehicles. Shims are also responsible for dissipating heat from the brake pad to prevent overheating in brake liquid system. The extent of the mentioned capabilities are a factor of the brake pad shim material.

Most shim materials used in Aftermarket, are designed with a trade-off of low price for quality. These cheap materials unable to effectively absorb noise within frequencies <NUM> and <NUM> to minimise brake noise. Moreover, these lower quality, lower price shim material are unable to dissipate heat in more demanding breaking conditions. This may cause brake fluid to boil and brake pads to glaze resulting in the fading of braking power and sudden premature brake failure.

This leads to injuries and fatalities among the car users and pedestrians. The quality of the brake pad shim material coating is very poor resulting in relatively poor heat dissipation properties.

<CIT> discloses an anti-squeal shim (<NUM>) comprising a metal layer (<NUM>), having mechanical bonding means (<NUM>, <NUM>), a pairs at the upper end and another at the lower end of the anti-squeal shim, said metal layer coated on one side thereof by a high temperature resistant layer, a compound layer (<NUM>), said anti-squeal shim comprising a hole (<NUM>) provided through the anti-squeal shim (see <FIG>, <NUM>, <NUM> and <NUM>, column <NUM>, lines <NUM> - <NUM>).

<CIT> discloses an anti-noise shim (<NUM>) comprising a metal layer (<NUM>) without through holes, having mechanical bonding means (<NUM>) with pointed tip (<NUM>), coupled to a graphite foil layer (<NUM>) (see <FIG> and paragraph [<NUM>]).

Therefore, there is the need to develop a new cost competitive anti-noise shim with improved heat dissipation and noise adsorption properties comparable to higher quality higher price already available on the market.

The present invention deals with a new anti-noise shim which overcomes the drawbacks of the prior art. This is achieved by the anti-noise shim comprising a perforated metal layer and a high temperature resistant layer and related methods for the production application thereof as defined in the independent claims.

Advantages with the anti-noise shim according to the present invention are that it provides excellent heat dissipation and noise absorption properties, whilst being durable, and well suited for mass production by a method comprising an environmentally friendly process.

Particular embodiments of the invention are described in detail herein below, as a way of example and not limited to, with reference to the attached figures, wherein:.

The applicant surprisingly and unexpectedly developed a new Anti-noise shim <NUM> comprising at least a perforated metal layer <NUM> and at least a high temperature resistant layer <NUM> faced/coupled together by mechanical bonding wherein the perforated metal layer comprises through holes <NUM> and sharped/pointed mechanical bonding means <NUM>, a continuous high temperature resistant layer <NUM>, in particular a continuous high temperature resistant layer <NUM> in correspondence of the through holes <NUM> of the perforated metal layer <NUM>, as clearly reported in the figures, such as <FIG>, <FIG>, <FIG>, and the high temperature resistant layer comprises fibres, a filler and a binder, and in particular,.

Anti-noise shim <NUM> comprising at least a perforated metal layer <NUM> and at least a high temperature resistant layer <NUM> faced/coupled together by mechanical bonding wherein the perforated metal layer comprises through holes <NUM> and sharped/pointed mechanical bonding means <NUM>, a continuous high temperature resistant layer <NUM>, in particular a continuous high temperature resistant layer <NUM> in correspondence of the through holes <NUM> of the perforated metal layer <NUM>, as clearly reported in the figures, such as <FIG>, <FIG>, <FIG>, and the high temperature resistant layer comprises fibres, fillers and a binder, said anti-noise shim further comprising:.

Anti-noise shim <NUM> comprising at least a perforated metal layer <NUM> and at least a high temperature resistant layer <NUM> faced/coupled together by mechanical bonding wherein the perforated metal layer comprises through holes <NUM> and sharped/pointed mechanical bonding means <NUM>, a continuous high temperature resistant layer <NUM>, in particular a continuous high temperature resistant layer <NUM> in correspondence of the through holes <NUM> of the perforated metal layer <NUM>, as clearly reported in the figures, such as <FIG>, <FIG>, <FIG>, and the high temperature resistant layer comprises fibres, a filler and a binder, said anti-noise shim further comprising a coating layer <NUM> bonded on the other side/face of the perforated metal layer;
or
Anti-noise shim <NUM> comprising at least a perforated metal layer <NUM> and at least a high temperature resistant layer <NUM> faced/coupled together by mechanical bonding wherein the perforated metal layer comprises through holes <NUM> and sharped/pointed mechanical bonding means <NUM>, a continuous high temperature resistant layer <NUM>, in particular a continuous high temperature resistant layer <NUM> in correspondence of the through holes <NUM> of the perforated metal layer <NUM>, as clearly reported in the figures, such as <FIG>, <FIG>, <FIG>, and the high temperature resistant layer comprises fibres, a filler and a binder, said anti-noise shim further comprising a second high temperature resistant layer <NUM>, a continuous high temperature resistant layer <NUM>, in particular a continuous high temperature resistant layer <NUM> in correspondence of the through holes <NUM> of the perforated metal layer <NUM>, as clearly reported in the figures, such as <FIG>, <FIG>, <FIG>, mechanically bonded on the other side/face of the perforated metal layer. Moreover, in the anti-noise shim according to any of the embodiments according to the present invention a further thin coating layer <NUM> might be applied on the high temperature resistant layer <NUM> when coupled with the perforated metal layer <NUM>.

As a perforated metal layer <NUM> according to the present invention is meant a metal layer having through holes <NUM>, in particular a metal layer with not less than <NUM> through hole per <NUM> square centimeter (cm<NUM>) of the surface of the metal layer, preferably <NUM> through holes/cm<NUM>, or <NUM>, <NUM>, <NUM>, <NUM> or <NUM> through holes/cm<NUM> of the surface of the metal layer.

In particular through holes have diameter not less than <NUM> and not more than <NUM>, preferably not less than <NUM> and not more than <NUM>.

In particular the perforated metal layer <NUM> has a thickness preferably of not less than <NUM> and not more than <NUM>, more preferably not less than <NUM> and not more than <NUM>.

Such a perforated metal layer <NUM> may e. g be comprised of iron, zinc-plated steel, stainless steel, aluminum or the like.

As mentioned, the high temperature resistant layer <NUM>, a continuous high temperature resistant layer <NUM>, in particular a continuous high temperature resistant layer <NUM> in correspondence of the through holes <NUM> of the perforated metal layer <NUM>, as clearly reported in the figures, such as <FIG>, <FIG>, <FIG>, comprises fibres, a filler and a binder. According to one embodiment, the binder is an elastomeric binder, but it may also be a non-elastomeric resin type binder. Compared to conventional rubber materials, the fibres make the material stronger and less elastic in the plane without considerably affecting the compression characteristics in the normal direction. Moreover, the fibres and the fillers reduce the amount of elastomeric binder in the layer, thereby making the layer less expensive. According to one embodiment, the fibres content in the high temperature resistant layer <NUM> is not less than <NUM>%, or <NUM>%, or <NUM>%, and not more than <NUM>% or <NUM>% by weight. However, for some applications the fibres content may be higher than <NUM>%, such as up to <NUM>% or up to <NUM>% or even up to <NUM> %. The fibres are selected from organic fibres depending on the specific application. Examples of organic fibres include: cellulose fibers cotton linters fibers (fibers coming from plants,in general) aromatic polyamide fibres, polyamide fibres other than aromatic polyamide fibres, polyolefine fibres, polyester fibres, polyacrylonitrile fibres, polyvinyl alcohol fibres, polyvinylchloride fibres, polyurea fibres, polyurethane fibres, polyfluorocarbon fibres, phenol fibres, or the like. According to one embodiment, the fibres comprises aromatic polyamide fibers. More preferably the the fibers are selected from inorganic fiber such as carbon fibres, glass fibre, ceramic fibre, rock wool, mineral wool, fused quartz fibre, chemical processed high silica fibre, fused alumina silicate fibre, alumina continuous fibre, stabilized zirconia fibre, boron nitride fibre, alkali titanate fibre, whiskers, boron fibre, wollastonite, basalt fibre. The filler may be an inorganic filler such as clay, ash, talc, barium sulfate, sodium bicarbonate, graphite, lead sulfate, tripoli, wollastonite, or an organic filler. The binder may be an elastomeric material of rubber type such as styrene-butadiene rubber (SBR), acrylonitrile-butadiene rubber (nitrile-butadiene rubber, NBR), isoprene rubber (IR), chloroprene rubber (CR), butadiene rubber (BR), isobutylene-isoprene rubber (IIR), ethylene propylene rubber (EPM), fluoro rubber (FPM), silicone rubber (Si), chlorosulfonated polyethylene (CSM), ethylene-vinylacetate copolymers (EVA), chlorinated polyethylene (CPE), chloro-isobutane-isoprene rubber (CIIR), epichlorohydrin rubber (ECO), nitrile isoprene rubber (NIR) or the like. Elastomers other than rubbers may also be used. According to alternative embodiments the binder is a resin type material such as a rubber modified phenolic resin, a phenolic resin, an epoxy resin or the like.

In particular the high temperature resistant layer <NUM> has a thickness preferably not less than <NUM> and not more than <NUM>, more preferably not less than <NUM> and not more than <NUM>.

According to one embodiment, the coating layer <NUM> is a visco-elastic layer. The visco-elastic layer may be a latex (SBR, NBR, chloroprene, acrylic or the like), synthetic resins (acrylic, phenolic or the like, PTFE, polyurethanes, a visco elastic adhesive such as an acrylic or silicone based adhesive or the like, but it may be any visco elastic material with suitable vibration absorption and thermal resistance properties at the conditions that a shim is subjected to when mounted in a disc brake.

In particular, the coating layer <NUM> has a thickness preferably not less than <NUM> and not more than <NUM>, more preferably not less than <NUM> and not more than <NUM>.

Said optional thin coating layer <NUM> comprises thermo-resistant polymeric material such as PTFE, silicones, polyurethanes, synthetic resins, in particular with a thickness of not less than <NUM> and not more than <NUM>, preferably not less than <NUM> and not more than <NUM>.

Said thin coating layer <NUM> is applied on the high temperature resistant layer <NUM> as a top layer.

Step application or bonding of coating layer <NUM> and/or thin coating layer <NUM> can be performed in different way: rolls, bath saturation, spraying, wetting, etc..

The anti-noise shim <NUM> according to any of the embodiments according to the present invention is an advanced anti-noise shim comprising multi-layer material with its application in the brake shims. It is made by mechanically bonding at least a high temperature resistant layer <NUM> comprising binders, an elastomeric material of latex rubber type such as specialized Nitrile Butadiene Rubber (NBR) Styrene Binder Rubber (SBR) latex material or the like, fibres, such as inorganic fibers, and fillers, with a perforated metal layer <NUM>. Said perforated metal layer <NUM> is characterized by through holes <NUM> and sharped/pointed mechanical bonding means <NUM>, jointly/united with the perforated metal layer <NUM> and, where present, located at the edge <NUM> of the through holes <NUM> on at least a mechanically bonding surface <NUM> of the perforated metal layer <NUM>. Perforated metal layer <NUM> having through holes <NUM>, absorbs resonant frequencies better than a solid metal layer. Moreover, the high temperature resistant layer <NUM> according to the present invention is produced from adapting gasket technology, which involves infusing the binder, such as raw NBR (or SBR or other types) Latex, with fibres and fillers. Said adapted gasket technology makes the anti-noise shims according to any of the embodiments according to the present invention more temperature resistant while the perforations of the metal layer <NUM> make it a perfect material for high frequency noise absorption.

The anti-noise shim according to the present invention is an advanced anti-noise shim comprising multi-layer composite wherein the perforated metal layer/sheet <NUM> is mechanically bonded with at least a, or sandwiched by mechanical bonding between two, high temperature resistant layer <NUM> comprising binders, an elastomeric material of rubber type, such as specialised Nitrile Butadiene Rubber (NBR) material, fibres, such as organic and inorganic fibers and fillers.

Perforating the metal layer/sheet facilitates the mechanical bonding step of the different shim layers. The noise absorption properties by leaving voids in the metal. Vibration of air molecules within the voids, due to the through holes <NUM>, of the perforated metal layer <NUM>, helps in dissipating high frequency noise being generated by the vibrations of the brake disk & pads thereby damping the noise.

The high temperature resistant layer <NUM>, according to the present invention, is produced from adapting gasket technology, which involves infusing the binder, an elastomeric material of rubber type, preferably the raw NBR (or SBR or other types) latex, with fibres, preferably the inorganic fibres, and fillers. NBR (or SBR or the like) latex is a milky white liquid emulsion of synthetic rubber. Overall the gasket technology is more resistant to higher temperatures than a <NUM>% NBR coated layer. Additionally, the perforated metal layer concept makes distribution of the high frequency vibrations much more effective and absorbed in the compound material easier. The mechanical bonding step (pressing the high temperature resistant layer/sheet <NUM>, according to the present invention, on the perforated metal layer <NUM> characterized by through holes <NUM> and sharped/pointed mechanical bonding means <NUM>, jointly/united with the perforated metal layer <NUM> and, where present, located at the edge <NUM> of the through holes <NUM> on at least a mechanically bonding surface <NUM> of the perforated metal layer <NUM> ) requires no gluing agent nor solvents to form a strong bond during the process. This eliminates the need of solvents used in actual technology for shim production. In the mechanical bonding step the pressure applied is sufficient to make the sharped/pointed mechanical bonding means <NUM> fold in on themselves to grip the perforated metal layer/sheet and the high temperature resistant layer/sheet to each other.

For "mechanical bonding means" <NUM> or "mechanical bonding means <NUM> " according to the present invention, it is meant means of bonding / mechanical constraint <NUM> or means of linking <NUM> or means of fastener <NUM> for the mechanical joining between the perforated metal layer <NUM> coupled with the high thermal resistant layer/s <NUM>.

The technical advantages due to the anti-noise shims according to any of the embodiments according to the present invention, the method to produce the same and the use thereof in a disc brake arrangement are as follows:.

It is a further object of the present invention the use of the anti-noise shims according to any of the embodiments according to the present invention in a disc brake arrangement comprising a calliper (brake caliper/brake calliper) and a brake pad, the anti-noise shim/anti-noise brake shim being configured to act between the calliper and the brake pad. <FIG> schematically show a number of embodiments of anti-noise shims <NUM> according to the present invention with at least a perforated metal layer <NUM> and at least a high temperature resistant layer <NUM> faced/coupled together by mechanical bonding wherein the perforated metal layer comprises through holes <NUM>.

The figures shall be regarded as illustrative only, and the relative dimensions of different layers have no significance. In particular, as an embodiment of the anti-noise shim according to the present invention, <FIG> shows an anti-noise shim <NUM> with at least a perforated metal layer <NUM> and at least a high temperature resistant layer <NUM> faced/coupled together by mechanical bonding wherein the perforated metal layer comprises through holes <NUM>, said anti-noise shim further comprising a coating layer <NUM> bonded on the other side/face of the perforated metal layer.

In particular, in <FIG> is shown the perforated metal layer <NUM> characterized by through holes <NUM> and sharped/pointed mechanical bonding means <NUM>, preferably with hook shape, at least one or two or three or four mechanical bonding means for each through hole, said mechanical bonding means jointly/united with the perforated metal layer <NUM> and, where present, located at the edge <NUM> of the through holes <NUM> on at least a mechanically bonding surface <NUM> of the perforated metal layer <NUM>, mechanically bonding surface on which is mechanically bonded the high temperature resistant layer <NUM>, while the coating layer <NUM> is bonded on the other side/face of the perforated metal layer.

In particular, as an embodiment of the anti-noise shim according to the present invention, <FIG> shows an anti-noise shim <NUM> with at least a perforated metal layer <NUM> and at least a high temperature resistant layer <NUM> faced/coupled together by mechanical bonding wherein the perforated metal layer comprises through holes <NUM>, said anti-noise shim further comprising a second high temperature resistant layer <NUM> mechanically bonded on the other side/face of the perforated metal layer.

In particular, in <FIG> is shown the perforated metal layer <NUM> characterized by through holes <NUM> and sharped/pointed mechanical bonding means <NUM>, preferably with hook shape, at least one or two or three or four mechanical bonding means for each through hole, said mechanical bonding means jointly/united with the perforated metal layer <NUM> and, where present, located at the edge <NUM> of the through holes <NUM> on the mechanically bonding surfaces <NUM> of the perforated metal layer <NUM>, mechanically bonding surfaces on which the high temperature resistant layers <NUM> are mechanically bonded. Moreover, a thin coating layer <NUM> is, or might be, applied as top layer on a high temperature resistant layer <NUM>.

There is also provided methods of producing anti-noise shim of the type disclosed herein.

The steps of the methods are schematically shown in <FIG> and <FIG>.

It is a further object of the present invention a method of producing anti-noise shim <NUM> in accordance with any embodiment of the present invention, said method comprising the steps:.

As a further method of producing anti-noise shim <NUM> in accordance with any embodiment of the present invention, said method comprises the steps:.

to form an anti-noise shim sheet, i.e. a method wherein the further high temperature resistant sheet is mechanically bonded on the opposite side of the perforated metal sheet respect where the temperature resistant material sheet <NUM> is mechanically bonded, or a method wherein two high temperature resistant sheets <NUM> are mechanically bonded on the opposite sides/both sides of the perforated metal sheet <NUM>, to form anti-noise shim.

to form an anti-noise shim sheet, i.e. a method wherein a coating sheet <NUM> is bonded on the opposite side of the perforated metal sheet <NUM> respect where the temperature resistant material <NUM> is mechanically bonded, to form an anti-noise shim.

Every of the above mentioned methods according to the present invention can optionally further comprise a step wherein a further thin coating layer <NUM> is applied/bonded on the high temperature resistant layer/sheet <NUM>, in particular when the high temperature resistant layer/sheet <NUM> is mechanically bonded/already mechanically bonded to the perforated metal layer <NUM>.

All the methods of producing anti-noise shims of the type according to the present invention are characterized by providing at least a perforated metal sheet/s <NUM>. Said perforated metal sheet <NUM> is obtained by perforation of metal sheet (Perforation is applied with a perforation machine, such as <NUM> or <NUM> perforating rolls or a high power hydraulic press that, with a specifically designed perforating mould/s, perforates the metal when said perforating mould/roll/s is/are pressed on a surface/side of the metal layer: perforation step) producing a perforated metal sheet with through holes <NUM> with sharped/pointed mechanical bonding means <NUM>, preferably with hook shape, at least one or two or three or four mechanical bonding means for each through hole, said mechanical bonding means jointly/united with the perforated metal layer <NUM> and, where present, located at the edge <NUM> of the through hole <NUM> on at least a mechanically bonding surface <NUM> of the perforated metal layer <NUM>. This perforation could be realized just on one side or on both sides of the metal layer/sheet.

Accordingly, the perforated metal layer/sheet <NUM> has through holes <NUM> with sharped/pointed mechanical bonding means <NUM>, preferably with hook shape, at least one or two or three or four mechanical bonding means for each through hole, said mechanical bonding means jointly/united with the perforated metal layer/sheet <NUM> and, where present, located at the edge <NUM> of the through holes <NUM> on at least a mechanically bonding surface <NUM> of the perforated metal layer <NUM>.

Said perforation step, when present in any embodiments of the method of producing anti-noise shim of the type according to the present invention, always precedes the step of providing the perforated metal sheet <NUM>.

In the perforation step the specifically designed perforating roll/mould/s has/have perforation tip/s, preferably but not only star shape tip/s (at least <NUM> tip per cm<NUM>), designed to produce through holes <NUM> in the metal layer/sheet and sharped/pointed mechanical bonding means <NUM>, jointly/united with the perforated metal layer <NUM>, located at the edge <NUM> of the through holes <NUM>, on the surface/side <NUM> of the perforated metal layer/sheet, which is opposite to the surface/side of the perforated metal layer/sheet on which the perforating roll/mould/s is pressed on.

When both surfaces/sides of the perforated metal layer/sheet have sharped/pointed mechanical bonding means <NUM> (I. both mechanically bonding surface <NUM>), the sharped/pointed mechanical bonding means on one surface/side are shifted with respect to the sharped/pointed mechanical bonding means on the other surface/side, i.e. each through hole <NUM> has sharped/pointed mechanical bonding means <NUM> at the edge <NUM> thereof on only one surface/side of the perforated metal layer/sheet (see <FIG>). Accordingly, in the corresponding perforation step, both surfaces/sides of the metal layer/sheet are perforated by pressing each face/side with a perforation mould/roll wherein the perforation tips of one perforation mould/roll are shifted with respect to the perforation tips of the other perforation mould/roll.

Bonding of different sheets to each other: bonding perforated metal sheet with high temperature resistant sheet/s by mechanical bonding, or bonding perforated metal sheet with high temperature resistant sheet by mechanical bonding and with coating sheet by bonding involving use of a bonding agent, such as resin, cyan, acrylic type adhesive or the like, or by vulcanization, may be performed in any suitable way providing a sufficiently strong bond there between. The bonding involve the step of applying pressure or pressure and heat or just heat. In order for the method to be efficient, the bonding may involve continuous rolling, whereby the perforated metal sheet and the high temperature resistant film/sheet/s are provided/ produced in the form coils <NUM> or rolls <NUM> respectively. In the bonding step <NUM>/<NUM>, comprising the mechanical bonding step, the pressure applied is sufficient to make the sharped/pointed mechanical bonding means <NUM>, of the perforated metal layer/sheet <NUM>, fold in on themselves to grip the perforated metal layer/sheet <NUM> and the high temperature resistant layer/sheet <NUM> to each other, while coating film/sheet <NUM> is applied/bonded by printing roll, spraying, wetting, bath saturation, etc.. Also the thin coating layer/sheet/film <NUM> is applied/bonded by printing roll, spraying, wetting, bath saturation, etc., when present.

Anti-noise shim/s of the type according to the present invention, are obtained as anti-noise shim sheet of the type according to the present invention, said anti-noise shim sheet of the type according to the present invention can be enrolled to form coils.

A further optional step of cutting out individual anti-noise brake shims from the anti-noise shim sheet, may be performed by any suitable method, such as stamping or similar methods. According to one embodiment, the method comprises the step of slitting <NUM> the coils into narrow coils after the bonding step <NUM>/<NUM>. Thereafter individual anti-noise brake shims are cut out from the narrow coils.

In order to achieve a strong bond and to minimize the steps in the bonding operation, the perforated metal sheet may be pre-treating with a bonding agent before the step of bonding <NUM>/<NUM>.

Also the step of pre-treating <NUM> may be performed in a continuous process. <FIG> show schematic examples of a continuous perforating, bonding and optionally cutting process line <NUM>. <FIG> shows a schematic example of a continuous perforating, bonding and optionally cutting process line <NUM>, wherein the perforated metal sheet <NUM>, obtained by a perforation machine <NUM> acting on a metal sheet provided in form of coils, not represented, and the high temperature resistant sheets <NUM> to be bonded together, are provided in the form of coils or rolls, not represented. The sheets <NUM> and <NUM> are pressed together and bonded by a pair of calender rolls <NUM> to form a layered anti-noise shim sheet according to the present invention. Optionally, a thin coating layer <NUM> is applied on the surface of the high temperature resistant layer of the layered anti-noise shim sheet by a wet application process <NUM>.

As a further optional step, individual anti-noise brake shims <NUM> are cut out from the anti-noise shim sheet by a stamping machine <NUM>. <FIG> shows a schematic example of a continuous perforating, bonding and optionally cutting process line <NUM>, wherein the perforated metal sheet <NUM>, obtained by a perforation machine <NUM> acting on a metal sheet provided in form of coils, not represented, and the high temperature resistant sheet <NUM> to be bonded together, are provided. The sheets <NUM>, and <NUM> are pressed together and bonded by a pair of calender rolls <NUM> to form a layered sheet. The coating layer <NUM> is applied on the no-bonded surface of the perforated metal layer <NUM> of the layered sheet by a wet application process <NUM> to form anti-noise shim sheet according to the present invention. As a further optional step, individual anti-noise brake shims <NUM> are cut out from the anti-noise shim sheet by a stamping machine <NUM>.

<FIG> shows a schematic example of a disc brake <NUM>, as an example of those disc brakes already known in the art, said disc brake <NUM> known in the art comprising a disc <NUM> arranged to rotate about the axis C-C. A pair of brake pads <NUM> each having a backing plate <NUM> supporting a friction member <NUM> on the disc side thereof, a brake calliper <NUM> supporting the brake pads <NUM> movably toward and away from opposite friction surfaces of the disc <NUM>, and hydraulic actuating means in the form of a brake piston <NUM> for urging the brake pads against the disc. The brake piston <NUM> is hydraulically actuated via the fluid path <NUM> connected to the hydraulic brake system of a vehicle. In the disclosed embodiment, the disc brake <NUM> the calliper housing <NUM> is moveable in the actuation direction of the brake piston, whereby the brake pad on the non piston side is urged against the disc by a calliper finger <NUM> of the calliper housing <NUM>. An anti-noise shim <NUM> is arranged adjacent the backing plate <NUM> of each disc pad <NUM> and the brake force from the brake piston <NUM> and calliper finger <NUM> respectively is transferred to the brake pads <NUM> via the anti noise shims <NUM>. Throughout this description, the expression "brake pad side" refers to the side of an anti noise shim <NUM> that face the backing plate <NUM> of a brake pad <NUM> and the expression "piston side" refers to the non pad side, i.e. the side that faces the piston <NUM> or the calliper finger <NUM>. In some disc brake designs, the calliper finger <NUM> is omitted and the calliper <NUM> is provided with brake pistons <NUM> on both sides of the disc <NUM>. However, throughout this description, the above expressions include any such non disclosed disc brake arrangements.

There is also provided a disc brake arrangement comprising an anti-noise shim according to anyone of the above embodiments between the calliper and the brake pad, and the disc brake may be arranged in a suitable vehicle -such as a car, truck, train, motorbike, bicycle etc..

Claim 1:
Anti-noise shim (<NUM>) comprising at least a perforated metal layer (<NUM>) and at least a high temperature resistant layer (<NUM>) faced/coupled together by mechanical bonding wherein the perforated metal layer comprises through holes (<NUM>) and mechanical bonding means (<NUM>), and the high temperature resistant layer comprises fibers, a filler and a binder material, said perforated metal layer <NUM> is characterized by through holes <NUM> and sharped/pointed mechanical bonding means <NUM>, jointly/united with the perforated metal layer <NUM> and, where present, located at the edge <NUM> of the through holes <NUM> on at least a mechanically bonding surface <NUM> of the perforated metal layer <NUM>..