Ventilated type brake band for disc brakes

Abstract

Brake band for ventilated type disc brakes The present invention relates to a brake band (1) for a ventilated-type disc brake disc (2) that is exceptionally capable of avoiding annoying whistling-inducing vibrations during braking. The brake band (1) extends between an inner diameter (D1) proximate an axis of rotation (XX) of the brake band (1) and an outer diameter (D2) distal from the axis of rotation (XX), the axis of rotation defining an axial direction (XX). The brake band (1) defines a radial direction (RR) substantially perpendicular to the axial direction (XX) and a circumferential direction (CC) perpendicular to both the axial direction (XX) and the radial direction (RR). The brake band (1) comprises two opposing plates (3, 4), the plates (3, 4) including inner surfaces (5, 6) directly or indirectly facing each other and defining a gap (7), and the plates (3, 4) including outer surfaces (8, 9) having flat, opposing circumferential portions that form braking surfaces (10, 11). The plates (3, 4) consist of plate bodies (12, 13) or plate thicknesses (14, 15) extending in the axial direction (XX), and the plates (3, 4) are joined to one another by heat dissipation or connecting elements (16, 17, 18, 19) in the form of pillars and / or ribs protruding from one plate towards the opposite plate in the form of a bridge connecting the plates (3, 4), and at least one of the plates (3, 4) is provided with at least one shaped pin (20, 21, 22) which allows the plate to reach the opposite plate (4; 3), thereby forming at least one local narrowing of the gap (7) and the thickness of the plate body (12; 13) and thus a local increase in the plate thickness (14, 15). At least one molded pin (20, 21, 22) extends from at least a first connecting element (16, 17, 18, 19) to an adjacent connecting element (16, 17, 18, 19) connecting the connecting elements (16, 17, 18, 19). At least one molded pin (20, 21, 22) extends at least along a circumferential direction (CC) connecting at least two adjacent connecting elements (16, 17, 18, 19) arranged side by side in the circumferential direction (CC), and each molded pin (20, 21, 22) extends circumferentially along a discontinuous annular path, avoiding an assembly of molded pins being uniformly distributed in the circumferential direction.

Description

[Technical Field]

[0001] The present invention relates to a brake band and a ventilated disc for disc brakes, and in particular to a vehicle having said ventilated disc, although this application is not limited to the automotive sector. [Background technology]

[0002] In a disc brake, a brake caliper is generally arranged to straddle the outer peripheral edge of a brake disc adapted to rotate about an axis of rotation (AA) defining an axial direction (XX). In a disc brake, a radial direction (RR) is also defined, which is substantially perpendicular to said axial direction (XX), a circumferential direction (CC) perpendicular to both said axial direction (XX) and said radial direction (RR), and a tangential direction (TT) locally, or better temporally, perpendicular to both said axial direction (XX) and said radial direction (RR).

[0003] As is known, a disc for a disc brake consists of a bell adapted to connect the disc to the vehicle hub, from which extends an annular section called a brake band intended to cooperate with the brake pads of a caliper. In the case of ventilated discs, the brake band is made up of two plates facing each other and connected to each other by connecting elements, for example in the form of pins or fins. The outer surfaces of the two plates define the opposing braking surfaces, while the inner surfaces, in cooperation with the pins or fins, define air channels for cooling the disc, i.e., passages through which air flows in a centrifugal direction during the rotational movement of the disc itself.

[0004] The brake band is intended to cooperate with a caliper for a disc brake adapted to apply braking force to a vehicle, and friction is applied to the opposing surfaces of the two plates (the aforementioned braking surfaces) by means of the aforementioned pads.

[0005] It is known that during braking, friction between the pads of the brake caliper and the braking surface of the brake band increases the amount of heat that must be dissipated.

[0006] The heat generated actually causes the occurrence of several undesirable phenomena such as deformation of the brake band, the formation of cracks on the braking surface or local changes in the state of the material forming the brake band, resulting in a deterioration of the brake band itself.

[0007] Particularly in high performance automotive applications where braking efficiency is increased, the energy to be dissipated is significantly higher and the aforementioned need to deal with the heat generated by braking action is even more felt.

[0008] Ventilated discs of the aforementioned type have undergone continuous evolution over the years, in particular with regard to the number and shape of the so-called ventilation channels that define the gap formed by the two plates axially facing each other.

[0009] Among the known breathable discs, the so-called "pin" discs have been shown to be particularly efficient in terms of heat dissipation, i.e. cooling, in which the air passages are confined from the inside by specific columnar connecting elements with limited or practically little deformation in radial and circumferential length relative to their axial extension, defined as "pins" that connect two plates laterally.

[0010] For example, a "pin" ventilated disc is known from EP 1 373 751 B1, in which the pins are geometrically arranged along three concentric circumferences coaxial with the disc and having different radii to form three "ranks", and when cross-sectioned in a plane parallel to and central to the two plates, the pins have different types of cross-section (e.g. pins with a "diamond" cross-section in the intermediate and inner ranks; "droplet-shaped" pins in the outer ranks).

[0011] Other ventilated discs with a "pin" structure are known, for example, from WO 2004 / 102028 and US Pat. No. 5,542,503.

[0012] Known ventilated discs include so-called "fin" or "tab" discs in which the air passages are confined internally by specific connecting elements, or spirals, elongated along a main direction oriented, for example, parallel to the radial direction (RR), connecting two plates laterally.

[0013] Similarly, the braking action performed by the pads against the braking surface of the disc is known to generate heat and therefore cause the temperature of the disc to rise to the point where the disc itself becomes white-hot, especially in the case of severe braking. The temperature of the disc rises during braking, which leads to deformation of the disc and poor contact between the pad and the braking surface. Furthermore, the friction material of the pad undergoes a kind of vitrification and becomes contaminated by the material of the disc.

[0014] Also, the highest temperatures are reached in the annular centre of the braking surface, i.e. in the annular centre of the outer surface of each plate, and cracks are likely to occur in such zones during the life of the disc.

[0015] In order to avoid the above-mentioned drawbacks, there is a particular need in this field to, on the one hand, increase the efficiency of the dissipation of the heat generated by braking so as to limit the temperature reached by the disc during and after braking, and, on the other hand, to increase the mechanical resistance of these central parts of the braking band.

[0016] Several solutions are known from WO 2004 / 102028, and WO 2002 / 064992, US 7,066,306, US 7,267,210, US 2006 / 0243546, US 2004 / 0124047, US 6,367,599, US 5,542,503 and US 4,865,167, which are satisfactory from various points of view, but these known solutions do not achieve a compromise between the desired mechanical resistance in the central annular zone of the braking band and the contrasting need to maximize in the same zone an air flow capable of eliminating the strong local temperature rise caused by the braking action.

[0017] It is worth noting, however, that the ventilated discs of the type mentioned do not themselves provide a solution to a further problem which arises at the same time as the problem mentioned above and which must be solved at the same time, but which can affect disc brakes, in particular disc brakes with ventilated discs, and which is briefly disclosed below.

[0018] As is known, during braking, the disc and in particular the brake band may mechanically vibrate at different frequencies that correlate with different vibration modes of the disc itself. Such vibrations of the disc may arise, for example, from resonances caused by vibrations of objects mechanically coupled to the disc that are stressed during the braking step, if the vibration frequency of such objects coincides with or is sufficiently close to the vibration frequency of the disc.

[0019] It is also known that the above vibrations produce audible noises, particularly annoying whistling-like noises, when the resonant frequency is in the audible range (for example between 2 and 9 kHz followed by a more or less sharp whistling sound).

[0020] Therefore, a need arises to devise a solution to reduce or eliminate such whistling noise by constructing a device that "shifts" the vibration frequency of the disk to a value different from that which is excited.

[0021] Several solutions are known for disks with structures different from the "pin" structure described above.

[0022] For example, IT1273754 has a brake band with protrusions that protrude on the inside of the plates towards the gap between the two plates to reduce the vibrations and subsequent noise that occur.

[0023] Other ventilated discs having a structure adapted to reduce annoying vibration phenomena are known, for example from US Pat. No. 4,523,666.

[0024] U.S. Patent No. 3,983,973 to Knorr-Bremse GmbH shows a brake disc including a pair of friction plates spaced apart to form an air passage. A brake pad / brake gasket may apply a braking force to the plates. The two friction plates are interconnected by a plurality of ribs or flow guide fins, forming an air passage between the friction plates. Radial grooves formed on the opposing surfaces of the friction plates contain strips of vibration-damping material. These inserts damp vibrations and are formed of metal elements with a coefficient of expansion greater than that of the ferrous material from which the friction plates are made, such as lead, bronze, or copper.

[0025] A similar solution is known from US2009 / 035598.

[0026] It is known from US 2012 / 111692 to couple a passive damper of the scook type to a braking system in order to reduce vibrations.

[0027] Known from US 6,131,707, WO2016 / 020820, WO2017 / 153902, WO2017 / 153873, EP0318687, WO2011 / 058594, WO2006 / 105131, US2006 / 219500, US 6,145,636. From US 2010 / 122880, US 6,325,185, US 4,523,666, US 5,004,078, SI 23474, GB 2060796, DE 102013210700, EP 3421833, WO 2015 / 092671, GB 2286438, DE 102004056645, EP 2192321, WO 2008 / 078352, US 3,983,973, DE 202006017092, US 2009 / 0000884, DE 202015102580 it is known to provide connections between plates of a braking band that are arranged unevenly in the circumferential direction in order to reduce vibrations excited by the braking action and to increase the air permeability in the gaps.

[0028] However, these distributions of the connecting elements of the plates create structural inhomogeneities which can generate quite unwanted stresses concentrated in the brake band under certain conditions of braking operation.

[0029] Therefore, a need arises for a new design of breathable discs that can simultaneously provide both efficient cooling performance and vibration and noise minimization characteristics during braking steps, and that can avoid concentrated stresses in the braking band that could impair its integrity and lifespan.

[0030] The above-mentioned known examples of breathable discs and associated brake bands do not adequately meet all of the needs that have been mentioned and are highly desired.

[0031] EP 2 715 179 B1 to the same applicant seeks to partially solve these problems and in particular to reduce the frequencies of vibration modes of the brake band that lead to vibrations outside the plane of the band plates themselves, in particular by providing a shaped pin arranged between the connecting elements and projecting into the gap.

[0032] Although satisfactory from many points of view, this known solution does not completely solve the problem and in particular highlights how there is a felt need to find a solution that makes it possible to obtain a shape for the surfaces that delimit the gaps in the brake band.

[0033] Therefore, there remains a strong need to increase the mass of the brake band near its outer edges in order to reduce "out-of-plane" type brake band vibration modes which, when excited, have a significant adverse effect on brake performance.

[0034] At the same time, there remains a strong need to maintain a distance between the molding pins and the connecting elements, especially close to the outer edge of the disc, in order to simplify the manufacturing process of the core, which allows for example to produce the brake band by molding. Since the shape of the pins is achieved by the core, which geometrically represents the space between one pin and another, it is necessary to ensure a minimum cross section so that the sand for the core can fill all the spaces that form the gaps, and furthermore, said core has a minimum cross section that allows it to provide its own structural resistance, sufficient for its handling and for the melting of the brake band.

[0035] Furthermore, there is a strong contrasting need to avoid large annular areas of clearance without connecting elements or protrusions, and therefore to avoid uneven distribution of temperature on the braking band, which could cause disc vibrations or other unbalance phenomena.

[0036] The problem underlying the present invention is therefore to devise a brake band and a disc for a disc brake having structural and functional characteristics that satisfy the aforementioned needs while avoiding the drawbacks mentioned with reference to the known art. Summary of the Invention

[0037] The present invention aims to provide a braking system that has a reduced tendency to produce such vibration waves and the subsequent whistling noise.

[0038] These and other objects and advantages are achieved by a brake band according to claim 1, by a disc brake disc according to claim 9 and by a vehicle according to claim 10.

[0039] Particular advantageous embodiments are the subject matter of the dependent claims.

[0040] From the analysis of this solution it became clear how the proposed solution makes it possible to achieve superior braking comfort with respect to prior art solutions and to reduce vibrations, in particular the absence of vibrations that cause whistling noise.

[0041] Furthermore, the proposed solution maintains a very high, and in some embodiments even improved, disc cooling efficiency, for example, which is strongly improved by the increased turbulence of the air flow through the gaps of the brake band, i.e., turbulence caused by the particular shape of the circumferentially extending molded pins located between the plates and the connecting elements.

[0042] Furthermore, the proposed solution makes it possible to increase the mass of the brake band located near its outer edge in order to reduce the "out-of-plane" type of brake band vibrations, which when excited have a significant negative effect on the performance of the brake.

[0043] Furthermore, the proposed solution allows for a certain distance between the mold pins and the connecting elements, especially near the outer edge of the disc, thus simplifying the manufacturing process. For example, to facilitate the realization of the casting core from which the brake bands are made, a minimum distance (variable from 5 to 7 mm, typically 6 mm) was determined to be required between the connecting elements and the mold pins. Since the shape of the connecting elements is determined by the core, which geometrically represents the space between one connecting element and another, a minimum cross-section is required to allow the molding sand to fill the entire space, as well as to guarantee the structural resistance of the core itself.

[0044] Furthermore, the proposed solution makes it possible to avoid large annular gap areas without connecting elements or shaped pins, and therefore to avoid uneven distribution of temperature on the braking band, which would cause disc vibrations or other imbalance phenomena.

[0045] Furthermore, the proposed solution allows for increased mass near the outer edge while structurally strengthening the band to limit crack formation and propagation while avoiding excessive blockage or narrowing of the air passages.

[0046] Furthermore, the proposed solution may ensure increased resistance to braking due to high temperatures.

[0047] Furthermore, shaped pins that can further increase the surface available for heat exchange are ensured by the proposed solution. [Brief explanation of the drawings]

[0048] Further features and advantages of the device, disc brake, and vehicle will become apparent from the following description of preferred, non-limiting embodiments thereof, with reference to the accompanying drawings, in which:

[0049] [Figure 1] FIG. 1 is an axial view of a brake band according to the present invention. [Figure 2] FIG. 2 is a plan view of the brake band of FIG. 1, taken along the central flow plane of the fluid flowing through the gap. [Figure 3] FIG. 3 is an enlarged detail view of a cross section of the brake band of FIG. [Figure 4] FIG. 4 is an axial view of a detail of the cross section of FIG. [Figure 5] FIG. 5 shows a cross section of the brake band in FIG. 1 along a plane including the axial and radial directions, in which further shaped pin shapes are noted. [Figure 6]FIG. 6 shows a cross section of the brake band of FIG. 1 along a plane including the axial and radial directions, in which the shape of the molded pin is marked. [Figure 7] 7 is an axial and partial cross-sectional view of the brake band in FIG. 1. FIG. [Figure 8] FIG. 8 is a cross-sectional view of a brake disc constituting a brake band according to the present invention, taken along a plane including the axial and radial directions. DETAILED DESCRIPTION OF THE INVENTION

[0050] According to a general embodiment, a disc brake band 1 for a disc brake 2 of the ventilated type is provided.

[0051] The brake band 1 extends between an inner diameter D1 close to the axis of rotation XX of the brake band 1 and an outer diameter D2 remote from the axis of rotation XX, which axis of rotation defines an axial direction XX.

[0052] The brake band 1 defines a radial direction RR that is substantially perpendicular to the axial direction XX, and a circumferential direction CC that is perpendicular to both the axial direction XX and the radial direction RR.

[0053] The brake band 1 has two plates 3 and 4 facing each other.

[0054] The plates 3, 4 face each other directly or indirectly and have inner surfaces 5, 6 defining a gap 7 which defines a ventilation duct for the brake band 1.

[0055] The plates 3, 4 have outer surfaces 8, 9.

[0056] The outer surfaces 8, 9 have flat, mutually opposing circumferential portions that form braking surfaces 10, 11. In other words, portions of the outer surfaces 8, 9 cooperate with brake pads received in a brake caliper to provide a braking action when pinched against the brake band 1. The portions of the outer surfaces 8, 9 that are brushed or caught by the pads define the braking surfaces 10, 11.

[0057] Said plates 3, 4 are made up of plate bodies 12, 13 extending in an axial direction XX and having a plate thickness 14, 15. That is to say, when evaluated in the axial direction, each plate 3, 4 exhibits a plate thickness 14, 15 given by the axial thickness of the plate body 12 of the plate 3, 4.

[0058] The plates 3, 4 are joined together by heat dissipation or connecting elements 16, 17, 18 of the plates 3, 4.

[0059] Said connecting elements 16, 17, 18 are in the form of pillars and / or ribs projecting from one plate towards the opposite plate in the form of a bridge connecting the plates 3, 4.

[0060] At least one of the plates 3,4 has at least one molded pin 20,21 that projects from said plate 3,4 into the gap 7 and thus reaches the opposite plate 4,3.

[0061] The forming pins 20, 21 form at least one local constriction of the gap 7. In other words, when traveling through the gap 7 and reaching the forming pins 20, 21, a cross-sectional reduction in the width of the gap 7 in the axial direction XX is detected.

[0062] The forming pins 20, 21 form at least one thickening of the plate bodies 12, 13 and thus cause a local increase in the plate thickness 14, 15. That is, when considering the thickness of the plate body in the axial direction XX, the thickness 14, 15 increases at the forming pins 20, 21.

[0063] According to a general embodiment, a brake band 1 of a disc 2 for a ventilated type disc brake extends between an inner diameter D1 close to an axis of rotation XX of the brake band 1 and an outer diameter D2 remote from said axis of rotation XX, said axis of rotation defining an axial direction XX.

[0064] The brake band 1 is characterized by defining a radial direction RR substantially perpendicular to the axial direction XX, a circumferential direction CC perpendicular to both the axial direction XX and the radial direction RR, and a tangential direction TT perpendicular to the axial direction XX and the radial direction RR.

[0065] The brake band 1 is composed of two plates 3 and 4 facing each other.

[0066] The plates 3, 4 have inner surfaces 5, 6 which face each other directly or indirectly and define a gap 7.

[0067] The plates 3 and 4 have plate bodies 12 and 13 each having a predetermined length in the axial direction XX or predetermined plate thicknesses 14 and 15 .

[0068] The plates 3 and 4 are joined together by heat dissipation and connection elements 16, 17, and 18 (also referred to as connection elements).

[0069] Said connecting elements 16, 17, 18 are formed as pillars and / or ribs and / or fins projecting from one plate towards the opposite plate and forming bridges connecting the plates 3, 4 to one another.

[0070] At least one of the plates 3,4 has at least one forming pin 20,21 protruding into the gap 7 from said plate 3,4 to the opposite plate 4,3, thus forming at least one local narrowing of the gap 7 and the thickness of the plate body 12,13 and forming a local increase in the plate thickness 14,15.

[0071] The at least one shaped pin (20,21) is separate from each connecting element (16,17,18), and the thickness of the at least one plate (3,4) with respect to the at least one shaped pin (20,21) is substantially equal to the predetermined plate thickness (14,15).

[0072] Said at least one shaped pin 20 advantageously extends forming at least two separate shaped pin branches 31,32.

[0073] According to one embodiment, the thickness of at least one plate 3,4 between said at least two formed pin branches 31,32 is substantially equal to said predetermined plate thickness 14,15.

[0074] According to one embodiment, said inner surfaces 5, 6 are flat surfaces.

[0075] According to one embodiment, the plates 3, 4 have outer surfaces 8, 9. The outer surfaces 8, 9 have flat, opposed annular portions that form braking surfaces 10, 11. The distance between the inner surfaces 5, 6 and the braking surfaces 10, 11 defines the predetermined plate thickness 14, 15.

[0076] According to one embodiment, the maximum axial width or length of said gap 7 is reached between said at least one shaped pin 20, 21 and each adjacent connecting element.

[0077] According to one embodiment, said at least one forming pin 20 and its at least two separate forming pin branches 31, 32 have a symmetrical shape with respect to a plane containing the axial direction XX and the radial direction RR.

[0078] According to an embodiment, the brake band 1 has an outer band edge 35 at the outer band diameter D2. When viewed in a plane containing the radial direction RR and the circumferential direction CC, the at least one shaping pin 20 and its at least two separate pin branches 31, 32 form a branch shaping pin 34, which presents a "V" shaped cross section forming a recess facing the outer edge of the disc.

[0079] According to one embodiment, when viewed on a plane having a radial direction RR and a circumferential direction CC, the at least one molding pin 20 and its at least two separate pin branches 31, 32 form a branched molding pin 34, and the branched molding pin 34 is crescent-shaped.

[0080] According to one embodiment, said at least one forming pin 20 consists of a cylindrically shaped central forming pin body 36 from which said at least two separate forming pin branches 31, 32 project.

[0081] According to one embodiment, the extensions of said at least two shaped pin branches 31 , 32 are arranged across at least one connecting element 16 .

[0082] According to one embodiment, the brake band 1 comprises a pin 21 with at least one further shape.

[0083] According to one embodiment, at least one extension of said at least two pin branches 31 , 32 intersects said at least one further shaped pin 21 .

[0084] According to one embodiment, the braking band 1 comprises at least two further shaped pins 21 arranged on the sides of the connecting element 16 .

[0085] According to one embodiment, each extension of said at least two pin branches 31, 32 intersects with a pin 21 having at least one further shape.

[0086] According to one embodiment, said at least one further shaped pin 21 is drop-shaped, as viewed in a plane having a radial direction RR and a circumferential direction CC.

[0087] According to one embodiment, said at least one further shaping pin 21 has a further shaping pin tapered extension 37 which is preferably tapered in a radial direction RR, directed towards said rotation axis XX.

[0088] According to one embodiment, the pin 21 with at least one further shape is a pin 21 with multiple further shapes.

[0089] According to one embodiment, the at least one further shaped pin 21 is a plurality of further shaped pins 21 arranged near the outer band edge 35 .

[0090] According to one embodiment, said at least one further shaping pin 21 is a plurality of further shaping pins 21 evenly distributed around the circumference.

[0091] According to one embodiment, said at least one further shaped pin 21 is a plurality of further shaped pins 21 arranged between a plurality of connecting elements 16 .

[0092] According to one embodiment, the at least one mold pin 20 and its at least two separate mold pin branches 31, 32 are a plurality of mold pins 20 each having a respective at least two separate mold pin branches 31, 32.

[0093] According to one embodiment, said at least one forming pin 20 and its at least two separate forming pin branches 31, 32 are a plurality of forming pins 20 evenly distributed around the circumference.

[0094] According to one embodiment, the at least one molded pin 20 and its at least two separate molded pin branches 31 , 32 are a plurality of molded pins 20 arranged at least partially between the connecting elements 17 .

[0095] According to one embodiment, at least one circumference concentric with the axis of rotation XX of the brake band 1, arranged on said inner surfaces 5,6 and intersecting said connecting elements 17 of the inner or intermediate rank, also intersects said at least one shaped pin 20.

[0096] According to one embodiment, at least one circumference concentric with the axis of rotation XX of the brake band 1, which is arranged on said inner surfaces 5, 6 and which intersects said connecting elements 16 of the outer rank, also intersects said at least one further shaped pin 21.

[0097] According to one embodiment, when viewed in a plane having a radial direction RR and a circumferential direction CC, the at least one molding pin 20 and its at least two separate pin branches 31, 32 form a branch molding pin 34, which has a rounded outer molding pin surface 38 connected to the inner surface 5 or 6 and protrudes therefrom into the gap 7.

[0098] According to one embodiment, when viewed in a plane containing the radial direction RR and the circumferential direction CC, the at least one further shaping pin 21 has a further shaping pin rounded outer surface 39 connected to the inner surface 5 or 6 and protruding therefrom into the gap 7.

[0099] According to one embodiment, the connecting elements 16, 17, 18 are grouped into at least two circumferentially arranged rows or ranks 23, 24, 25. A first of the ranks 23 is arranged radially closer to the inner diameter D1 or inwardly towards the axis XX, while a second of the ranks 24 is arranged further radially from the axis XX closer to the outer diameter D2.

[0100] According to one embodiment, at least one third of the ranks 24 are radially disposed between the first inner row 23 and the second outer row 24 .

[0101] According to one embodiment, each of the second connecting elements 16 of the rank 24 has three shaped pins or a combination of shaped pins facing it on three sides, and further shaped pins 20,21.

[0102] According to one embodiment, said at least one shaped pin 20 or 21 is at least a plurality of shaped pins, each of said plurality of shaped pins 20 or 21 being arranged between connecting elements 16 or 17 of the same rank 23, 24.

[0103] According to one embodiment, at least some of said connecting elements 16, 17, 18 are fins or ribs having an elongated shape in a plane substantially parallel to the air flow along the gap 7, for example in the radial direction RR.

[0104] According to one embodiment, said connecting element 16 close to the outer band diameter D2 or outer rank 24 has an elongated drop-shaped cross section in the radial direction RR on a plane substantially parallel to the air flow along the gap 7.

[0105] According to one embodiment, at least two of said connecting elements 17, 18 have, in a plane substantially parallel to the air flow along the gap 7, a rhombus or diamond-shaped cross section 27 with four vertices 28 joined by four side surfaces 29, said side surfaces delimiting said cross section being substantially rectilinear in shape.

[0106] According to one embodiment, all of the forming pins 20, 21 are arranged in a circular portion of the gap 7 close to the band outer diameter D2.

[0107] According to one embodiment, all of said shaped pins 20, 21 are located in the circular part of said gap 7 close to where the outer ranks 24 of the connecting elements 16 are located.

[0108] The present invention also relates to a disc brake disc 2 that constitutes the brake band 1 according to any one of the above-described embodiments.

[0109] The invention also relates to a vehicle equipped with a brake band 1 according to any one of the above-described embodiments.

[0110] Those skilled in the art may make some modifications and adaptations to the above-described embodiments and may substitute other functionally equivalent elements to meet accidental and particular needs, without, however, departing from the scope of the following claims.

[0111] The clusters of shaped pins 20, 21 arranged close to one another form groups of shaped pins 20, 21 arranged circumferentially and therefore have circumferential discontinuities concentrated near the outer diameter D2 of the brake band, making it possible to form an uneven distribution of the clusters of shaped pins, i.e. a distribution adapted to avoid the existence of vibration modes of the brake band 1 which, if arranged in resonance, would produce annoying sounds or whistling noises.

[0112] An embodiment of the present invention will be described below.

[0113] According to one embodiment, the brake band 1 has an outer diameter D2 of 415 mm, an inner diameter of 295 mm and a thickness of 33 mm.

[0114] The gap 7, i.e. the ventilation channel, has an estimated height in the axial direction XX of 12.6 mm.

[0115] The two plates 3, 4 are connected to each other by connecting elements 16, 17, 18 in the form of rows arranged over three concentric rows or ranks 23, 24, 25, said connecting elements 16, 17, 18 being arranged according to a staggered arrangement.

[0116] The connecting elements of the outer rank 24 have a drop shape evaluated on the average flow surface moving through the gap 7, and are oriented according to the radial direction RR and have tapered extensions pointing towards the axis of rotation XX.

[0117] The connecting elements 17 , 18 of the middle rank 25 and the inner rank 23 have a diamond shape evaluated on the mean flow plane moving through the gap 7 .

[0118] Each rank has 47 connection elements 16, 17 or 18.

[0119] Further shaped pins 21 are present in the outer ranks 23 between each connecting element 16. Said further shaped pins 21 have a drop shape in a plane containing the radial direction RR and the circumferential direction CC and have a tapered extension oriented according to the radial direction RR and facing the axis of rotation XX.

[0120] The shaped pin 20 is present at an intermediate rank 25 between each connecting element 17. The further shaped pin 20 has, in a plane containing the radial direction RR and the circumferential direction CC, a branch shape 34, i.e. a cylindrical central body from which first and second shaped pin branches 31, 32 project separately from each other.

[0121] The forming pin 20 has an axial length of 3.4 mm. The base of the forming pin 20 has a radius of 4 mm. The forming pin 20 has an overall height of 9.7 mm and an overall width including the branches of 13.5 mm.

[0122] The outer surface 38 of the molded pin 20 is joined to a flat inner surface 5 or 6 with a radius of 2 mm.

[0123] A modal analysis carried out in the frequency range 20-10,000 Hz (using a material with a Young's modulus of 112,000 MPa, a Poisson's ratio of 0.263 and a density of 7.113 kg / dm) showed the following notable values compared to the solution described in EP2715179 B1 of the same applicant:

[0124] [Table 1] [Explanation of symbols]

[0125] 1: Brake band 2: Disc brake disc 3: Plate 4: Plate 5: Inner 6: Inner self 7: Gap 8: Exterior 9: Outer surface 10: Braking surface 11: Braking surface 12: Plate body 13: Plate body 14: Plate thickness 15: Plate thickness 16: Connected components 17: Connected components 18: Connected components 20: Molded pin 21: Molding pin 23: Rank 24: Rank 25: Rank 26: Pin 27: Fin or rib 28: A rhombus or diamond with four vertices 29: Diamond side 31: First molded pin branch 32: Second molded pin branch 33: Bell 34: Branched molded pin 35: Outer band 36: Central molded pin body 37: Tapered extension of further formed pin 38: Outer pin surface 39: Outer surface of pin with further shape AA: Brake band or brake disc rotation axis XX: Rotational or axial direction RR: Radial direction CC:Tangential direction D1: Band inner diameter D2: Band outer diameter

Claims

1. A brake band (1) for a ventilated type disc brake, the brake band (1) extends between an inner diameter (D1) close to an axis of rotation (A-A) of the brake band (1) and an outer diameter (D2) remote from the axis of rotation (A-A), the axis of rotation (A-A) defining an axial direction (X-X); the brake band (1) defines a radial direction (R-R) perpendicular to the axial direction (X-X), a circumferential direction (C-C) perpendicular to the axial direction (X-X) and the radial direction (R-R), and a tangential direction (T-T) perpendicular to the axial direction (X-X) and the radial direction (R-R); The brake band (1) comprises two plates (3, 4) facing each other, the two plates (3, 4) include inner surfaces (5, 6) that are directly or indirectly opposed and define a gap (7) between the two plates (3, 4); The two plates (3, 4) have plate bodies (12, 13) having predetermined plate thicknesses (14, 15) in the axial direction (X-X), The two plates (3, 4) are joined together by a plurality of connecting elements, which are heat dissipation and connecting elements; the plurality of connecting elements are formed as pillars, ribs or fins each protruding from one of the two plates (3, 4) towards the other of the two plates (3, 4), thereby forming a bridge connecting the two plates (3, 4) to each other; At least one of the two plates (3, 4) has at least one first molded pin (20) that protrudes from one of the two plates (3, 4) into the gap (7) and reaches the other of the two plates (3, 4); The plurality of connection elements include a first connection element (16) and a second connection element (17), and the first connection element (16) is disposed outside the second connection element (17) in the radial direction (R-R); The first shaping pin (20) is arranged such that, with respect to the radial direction (R-R), a radially inner end of the first shaping pin (20) is located radially outward of the radially inner end of the second connecting element (17) and radially inward of the radially (R-R) outer end of the second connecting element (17), and such that the radially (R-R) outer end of the first shaping pin (20) is located radially outward of the radially (R-R) outer end of the second connecting element (17) and radially inward of the radially (R-R) inner end of the first connecting element (16); The first forming pin (20) has a central forming pin body (36) and two pin branches (31, 32) extending outward from the central forming pin body (36) in the radial direction (R-R) and on opposite sides in the circumferential direction (C-C), The brake band (1) is configured such that the first molded pin (20) has two pin branches (31, 32) that straddle the first connecting element (16) in the circumferential direction (CC).

2. The inner surfaces (5, 6) of the two plates (3, 4) are flat surfaces, The two plates (3, 4) each include an outer surface (8, 9); Each of said outer surfaces (8, 9) includes a flat annular portion forming a braking surface (10, 11); the distance between the inner surface (5, 6) and the outer surface (8, 9) defines the predetermined plate thickness (14, 15); 2. The brake band (1) according to claim 1, wherein the size of the gap (7) in the axial direction (X-X) is greatest between the at least one molded pin (20) and the connecting element (16, 17) adjacent to the first molded pin (20).

3. 3. A brake band (1) according to claim 1 or 2, wherein the first shaped pin (20) is "V" shaped or "crescent shaped" symmetrical with respect to a plane containing the axial direction (X-X) and the radial direction (R-R) and wherein the two pin branches (31, 32) have opposing recesses on the outer diameter (D2).

4. At least one of the two plates (3, 4) includes at least one second forming pin (21) located radially outward of the first forming pin (20) in the radial direction (R-R), protruding from one of the two plates (3, 4) into the gap (7) and reaching the other of the two plates (3, 4); 4. The brake band (1) according to claim 1, wherein the second shaped pin (21) is arranged so that extension lines of the two pin branches (31, 32) intersect with the second shaped pin (21).

5. 5. The brake band (1) according to claim 4, wherein the second shaped pin (21) tapers inward in the radial direction (R-R) on a plane including the radial direction (R-R) and the circumferential direction (C-C).

6. A braking band (1) according to claim 5, wherein said second shaped pin (21) is drop-shaped on a plane containing said radial direction (RR) and said circumferential direction (CC).

7. 7. The brake band (1) according to claim 4, wherein the second shaped pins (21) are arranged between adjacent first connecting elements (16) in the circumferential direction (C-C).

8. 8. The brake band (1) according to any one of claims 4 to 7, wherein at least a portion of the first molded pin (20) is arranged between adjacent second connecting elements (17) in the circumferential direction (C-C).

9. On a plane including the radial direction (R-R) and the circumferential direction (C-C), the central forming pin body (36) of the first forming pin (20) has an outer surface (38) that is rounded toward the axis of rotation (A-A); The second molded pin (21) has a generally rounded outer surface (39). A brake band (1) according to any one of claims 4 to 8.

10. The plurality of connection elements further includes at least one third connection element (18) disposed inside the second connection element (17) in the radial direction (R-R), The connection elements are grouped into three ranks; the third connecting element (18) forms a first rank (23); the first connecting elements (16) form a second rank (24); the second connecting elements (17) form a third rank (25); A brake band (1) according to any one of claims 4 to 9.

11. The first forming pins (20) are arranged in the third rank (25); 11. Braking band (1) according to claim 10, wherein said second formed pins (21) are arranged in said second rank (24).

12. 12. The brake band (1) according to any one of claims 1 to 11, wherein the second connecting element (17) has a diamond-shaped or lozenge-shaped cross section (27) having four side surfaces (29) and four vertices (28) connecting the four side surfaces (29) on a plane including the radial direction (R-R) and the circumferential direction (C-C).

13. A disc for a disc brake, comprising a brake band (1) according to any one of claims 1 to 12.

14. A vehicle comprising a brake band (1) according to any one of claims 1 to 12.

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