Disc brake disc and manufacturing method and system thereof

Abstract

A method for manufacturing a disc brake disc comprises the following steps: providing at least one sheet material having a predetermined thickness; punching out a first disc-shaped portion in the sheet material; punching out a second disc-shaped portion in the sheet material; punching out a third portion in the sheet material, which is suitable for manufacturing at least one ventilation spacer for a ventilated brake band; drawing the third portion by shaping a first protrusion and a second protrusion along a circular path on the third portion, thereby forming opposite first and second recesses, which are suitable for manufacturing a ventilation channel for the ventilated brake band; connecting the first disc-shaped portion to the first protrusion by a discontinuous weld spot; connecting the second disc-shaped portion to the second protrusion by a discontinuous weld spot. A system for manufacturing a disc brake disc capable of performing the above manufacturing steps and a disc brake disc for a disc brake manufactured according to the above manufacturing steps are also provided.

Description

Technical Field

[0001] The invention relates to a brake band and to a disc for a ventilated disc brake and to a method for producing the brake band. Background Art

[0002] In a disc brake, a brake caliper is usually arranged to straddle the outer periphery 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) arranged substantially orthogonal to said axial direction (XX) and a tangential direction (CC) or circumferential direction (CC) orthogonal to both said axial direction (XX) and said radial direction (RR) are also defined.

[0003] As is known, a disc for a disc brake comprises a bell or a support portion suitable for associating the disc with the hub of a vehicle, from which extends an annular portion known as the brake band, intended to cooperate with the pads of the caliper. In the case of a ventilated disc, the brake band is made with the aid of two plates respectively facing each other and respectively connected to each other by a connecting element, for example in the form of a column or a fin. The outer surfaces of the two plates define opposite braking surfaces, while the inner surfaces, together with the columns or fins, define ventilation channels for cooling the disc, through which an air flow passes according to a centrifugal direction during the rotational movement of the disc itself.

[0004] Said brake band is intended to cooperate with a disc brake caliper adapted to apply a braking action to the vehicle by exerting friction by means of pads on the opposite surfaces of two plates, called braking surfaces.

[0005] It is known that during operation of the brakes, the friction between the pads of the brake calipers and the braking surface of the brake band generates a considerable amount of heat which needs to be disposed of.

[0006] The heat generated can indeed lead to undesirable phenomena such as, for example, deformation of the brake band, the formation of cracks on the braking surface or local changes of state of the material forming the brake band, which in turn leads to a deterioration of the brake band itself.

[0007] Particularly in high performance motor vehicle applications where braking efficiency is increased, there is more energy to be processed and a greater need to manage the heat generated during braking action.

[0008] Ventilation disks of the above-mentioned type have undergone continuous evolution over time, in particular as regards the number and shape of the so-called ventilation channels defining the gap formed by the two plates axially facing each other.

[0009] It is also known that the braking action provided by the pad against the braking surface of the disc generates heat and therefore, in particularly demanding performance situations, the temperature of the disc increases to such an extent that the disc itself becomes incandescent. Due to the increased temperatures reached by the disc during braking, the brake disc deforms and the contact between the pad and the braking surface deteriorates. In addition, the friction material of the pad is subject to vitrification and contamination from the disc material.

[0010] In order to eliminate the above drawbacks, there is a particular need in the art to improve, on the one hand, the efficiency of dissipating the heat generated by braking in order to control the temperature reached by the brake disc during and after braking, and, on the other hand, to increase the mechanical resistance of these intermediate portions of the brake band.

[0011] However, it should be noted that ventilated discs of the type described above do not by themselves provide a solution to other problems that may affect disc brakes, particularly disc brakes having ventilated discs, which arise concurrently with the above problems and need to be solved concurrently. This problem is briefly described below.

[0012] In particular, there is a need to provide discs for ventilated disc brakes also for mass-produced automotive or motorcycle applications, in which the brake band is obtained by punching out a steel sheet, e.g. the brake band is obtained by punching out and forming two sheets which are then connected together by gluing or brazing.

[0013] Such solutions are known from DE 34 32 926 A1 and US 2017 097 058.

[0014] It is also known to use two blanks with interposed fins or spacer rings and joined together by brazing.

[0015] A solution of this type is known from GB2437745.

[0016] Although these known solutions are suitable for mass production, they only result in products with low mechanical properties and susceptible to corrosion, since the brazing process significantly impairs the entire area of ​​the brake band plate that interacts with the brake pad and uses a low-melting alloy that is susceptible to corrosion. In addition, these known solutions produce a brake band structure that is strongly preloaded or biased by the welding effects distributed over a large surface of areas with mutually different masses and thermal and mechanical resistances. These effects usually lead to the need for long and expensive heat treatment processes of the brazed parts and subsequent deep chip removal machining, which makes the entire production process very laborious and sometimes even expensive.

[0017] Similar solutions are known from US3730304 and US2013284549.

[0018] Known solutions are those that place separate spacers between the plates and then connect the plates to the spacers by brazing the entire strip (as in FR2927389), or those that weld shaped spacers to the plates (as in US3623579 and US3486218). In particular, these solutions weld the shaped spacers along a line, which creates two types of problems. The first type of problem is that the weld line, extending over the entire height of the brake band, creates a circumferentially variable or cyclic structural discontinuity, which significantly increases the wear unevenness of the pad friction material, thus generating abnormal wear and particularly annoying noises during the braking action of the vehicle. The second type of problem is the inhomogeneity of the mechanical characteristics caused by the welding, where the material in the weld is harder but also more brittle, further increasing the wear unevenness of the pad, but also abnormal and uneven wear of the disc itself, which leads to the need to replace the disc long before the end of its actual service life.

[0019] Therefore, there is a need for new ventilated disc structures which can provide particularly effective cooling performance during the braking step, while being also easy to produce. In particular, from a mechanical point of view, and especially from a thermal point of view, there remains a strong need to extend the use of disc brake discs obtained by blanking from sheet metal to heavy-duty applications using efficient and cost-effective industrial processes.

[0020] The aforementioned known examples of ventilated discs and corresponding brake bands do not adequately meet all of the mentioned highly desirable requirements.

[0021] The problem underlying the present invention is therefore to provide a brake band and a disc for a brake disc having structural and functional properties that meet the above requirements and at the same time solve the drawbacks mentioned with reference to the prior art. Summary of the invention

[0022] The object of the present invention is to provide a braking device in which the tendency to generate these waves and the attendant noise is reduced.

[0023] This object and other objects and advantages can be achieved by a method for manufacturing a brake disc, and a disc brake disc and a system for implementing the above method according to the present application.

[0024] An analysis of the solution shows that, compared to the prior art solutions, the proposed solution allows achieving a higher braking comfort despite the use of a disk of material punched out of a sheet.

[0025] Furthermore, the proposed solution maintains a very high efficiency in cooling the disk.

[0026] In particular, according to the proposed solution, it is possible to extend the use of disc brake discs obtained by punching from at least one metal sheet to heavy-duty applications using an efficient and cost-effective industrial process from a mechanical point of view, in particular a thermal point of view.

[0027] The newly proposed solution enables the production of lightweight and corrosion-resistant discs with high mechanical strength and longer life and more uniform wear compared to solutions of the known art. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Further features and advantages of the device, the brake disc and the vehicle will become apparent from the following description of preferred embodiments of the device, the brake disc and the vehicle, shown by way of non-limiting example, with reference to the accompanying drawings, in which:

[0029] - Figure 1 is an axonometric view of a disc brake disc, in which the bell is obtained by drawing the central part of a stamped sheet disc; in this embodiment, the plate is welded to the ventilation spacer at mutually spaced and discreet points by at least one electrode (for example by capacitor spot welding), the at least one electrode reaching the opposite plate through a special opening in the plate;

[0030] - Figure 2 is a perspective view of a disc brake disc, in which the bell is obtained by drawing the central part of a stamped sheet disc; in this embodiment, the plate is welded to the ventilation spacer at mutually spaced and inconspicuous points by means of a plurality of electrodes (or a single electrode with a plurality of welding tips, for example by capacitor spot welding) which touch the opposite plate (according to the first plate or the second plate) through a plurality of openings made in the plate;

[0031] - Figure 3 is a perspective view of a disc brake disc in which the bell is obtained by eutectic melting of the bell on the inner radial extension of a brake band made from a component made from a blank; in this embodiment, the plates are welded to the ventilation spacers at mutually spaced and inconspicuous points by means of at least one electrode (for example by capacitor spot welding) which reaches the opposite plate through a special opening in the plate;

[0032] - Figures 4 to 6 is a perspective view of the three components of the brake band which, when assembled and welded together, form Figure 1 of the plate;

[0033] - Figure 7 yes Figures 4 to 6A side view of the three parts of the ventilated spacer, superimposed on each other and ready to be arranged side by side so as to align the openings suitable for receiving the welding electrodes with the recesses present in the ventilated spacer;

[0034] - Figure 8 yes Figures 4 to 6 a side cross-sectional view of a detail of three parts of the plate superimposed on each other and in contact with each other, wherein a welding electrode enters an opening in the plate to reach the surface defining the recess of the ventilation spacer and is ready to weld the ventilation spacer at a point at an opposing plate resting on a corresponding protrusion of the ventilation spacer, thereby forming a weld spot;

[0035] - Figures 9 to 11 is a perspective view of the three components of a brake band which, when connected and welded together, form Figure 2 of the plate;

[0036] - Fig.12 yes Figures 9 to 11 A side view of three components in which the three components are superimposed on each other and are ready to be placed side by side so that the openings suitable for receiving multiple welding electrodes (or a single electrode with multiple welding tips) are aligned with the recesses present in the ventilation spacer;

[0037] - Fig.13 yes Figures 9 to 11 a side cross-sectional view of a detail of three parts in a superimposed and contacting arrangement, wherein two opposing welding electrodes (in this section two welding tips of a single first welding electrode on the upper side and a welding tip of a single opposing welding electrode on the lower side can be seen) enter the plate opening to reach the surface defining the recess of the ventilation spacer and are ready to weld the ventilation spacer at a plurality of individual weld points at an opposing plate resting on corresponding projections of the ventilation spacer;

[0038] - Fig.14 and Fig.15 Is to prepare according to Fig.13 Several welding points and welding according to Fig.13 Schematic and perspective views of two steps of several welds of the invention, in which the welding tips can be seen, a first welding tip 28 of major extension extending into the plate opening and reaching the protrusion of the ventilation spacer resting on the opposite plate, and a second welding tip 29 of smaller extension extending to contact the plate, for example in which the hole 19 is formed;

[0039] Fig.16 yes Fig.15 A side cross-sectional view of the detail requiring two weld points;

[0040] Figures 17 to 20is a side view of a detail of an assembled assembly of three components of a brake band, said three components forming the brake band when assembled and welded together, wherein, after openings are formed in said plate and said vent spacer, said openings are aligned with one another to insert a welding stud in each of said openings and to weld so as to join said three components with opposing electrodes placed in contact with said welding studs by locally melting said welding studs and making them integral with said plate and said vent spacer;

[0041] Fig. 22 is a perspective view of a blanked plate with an inner radial extension for connection to a bell;

[0042] Fig.23 It includes Fig.21 A perspective view of the brake band of the plate shown in ;

[0043] Fig.23 is a perspective view of a disc brake rotor with a bell-shaped piece around it. Fig. 22 eutectic in said inner radially extending portion of the brake band;

[0044] Fig.24 and Fig.25 The bell-shaped piece surrounds Fig. 22 A perspective view of the two steps of the co-stamping process of the inner radial extension of the brake band in the first step of which the brake band is inserted into the mold ( Fig.24 ), and the second step is to reopen the die after co-punching the bell-shaped member around the inner radial extension of the strip;

[0045] Fig.26 is with Fig. 22 A perspective view of a brake band similar to the brake band in FIG. 1 , in which the inner radial extension 15 has been machined to receive the connection and feed device 30 to a support wheel 17 typically used for motorcycle applications;

[0046] Fig. 27 and Fig.28 are schematic and perspective views of two steps of simultaneously preparing and welding more than one welding spot according to a variant of embodiment, in which an annular welding plate can be seen, which is suitable for resting on the entire extension of the opposite braking surface of the plate and allows making an annular welding plate with a boss 19 therein;

[0047] Fig.29 yes Fig. 27 A cross-sectional view in the axial direction;

[0048] Fig.30 yes Fig.28 A side cross-sectional view of a detail of the embodiment of the present invention highlights the two opposing welding plates or ring electrodes indicated by reference numeral 33. DETAILED DESCRIPTION

[0049] According to a general embodiment, a brake band 4 for a disc of a ventilated disc brake 1 is provided.

[0050] The braking band 4 extends between an inner diameter D1 close to the rotation axis XX of the braking band 1 and an outer diameter D2 away from the rotation axis XX. The rotation axis defines an axial direction XX.

[0051] Said braking band 1 defines a radial direction RR substantially orthogonal to said axial direction XX and a circumferential direction CC orthogonal to both said axial direction XX and said radial direction RR.

[0052] The brake 1 comprises two plates 3 , 6 facing each other.

[0053] Said plates 3 , 6 comprise inner surfaces facing each other directly or indirectly and defining a gap defining a ventilation duct 13 for the braking band 4 .

[0054] The plates 3, 6 comprise an outer surface.

[0055] The outer surface comprises opposite flat circumferential portions which form the braking surfaces 26, 27. In other words, portions of the outer surface cooperate with a brake pad received in the brake caliper to apply a braking action when the brake pad is clamped against the brake band 4. The portions of the outer surface which are wiped or contacted by the pad define the braking surfaces 26, 27.

[0056] Said plates 3, 6 comprise a plate body having an extension extending in the axial direction XX or plate thickness. In other words, when viewed in the axial direction, each plate exhibits a plate thickness given by the thickness of the plate body of the plate 3, 6 in the axial direction.

[0057] Said plates 3 , 6 are joined to each other by means of heat dissipating elements or connecting elements made of at least one ventilated spacer 8 .

[0058] The ventilation spacers 8 are shaped as columns and / or ribs or fins which protrude from one plate towards the opposite plate in the shape of a connecting bridge of the plates 3 , 6 .

[0059] For example, the ventilation spacer 8 is made of a single shaped disk having projections 9,10 forming recesses 11,12. Each projection 9,10 has a flat portion 20 of the projection at the end of the projection, which adjoins the plates 3,6.

[0060] The invention also relates to a manufacturing method.

[0061] According to the general embodiment of the method, a method for manufacturing a disc brake disc 1 is provided. The method comprises the following steps:

[0062] - providing at least one sheet having a predetermined thickness;

[0063] - punching out a first disk-shaped portion 2 in at least one sheet, the first disk-shaped portion 2 being suitable for producing a first plate 3 of a ventilated brake band 4;

[0064] - punching out in at least one sheet a second disk-shaped portion 5 suitable for manufacturing a second plate 6 of said ventilated brake band 4;

[0065] - punching out in at least one sheet a third portion 7 suitable for producing at least one ventilated spacer 8 for said ventilated brake band 4;

[0066] - drawing said third portion 7 by shaping first 9 and second 10 projections along a circular path on said third portion 7 so as to form first 11 and second 12 opposite recesses suitable for making a ventilation channel 13 for said ventilated brake band 4;

[0067] - connecting said first disc-shaped portion 2 suitable for making a first plate 3 to said first projection 9 by means of discontinuous welds 14;

[0068] - connecting said second disk-shaped portion 5 , suitable for making a second plate 6 , to said second projection 10 by means of discontinuous welds 14 .

[0069] According to an embodiment, at least one sheet is made of a steel suitable for brake disc applications.

[0070] According to an embodiment, said at least one sheet is made of a stainless steel suitable for brake disc applications.

[0071] According to an embodiment, a bell 16 is provided which is associated with said braking band 4 and in which said bell is made of a material different from the material from which said braking band 4 is made.

[0072] According to an embodiment, said bell 16 is made of aluminium.

[0073] According to some embodiments, the bell 16 may be made of one of the following alternatives:

[0074] - eutectic aluminium on the inner radial extension 15 of the braking band 4; or

[0075] - is made of aluminium and is fitted to the brake band 4 by means of a small component, namely the connecting device 30; or

[0076] - steel material connected to the brake band 4 by means of a small component, namely the connecting device 30; or

[0077] - steel installed by deformation (e.g. according to the applicant's Blechtopf® solution); or

[0078] - Composite materials.

[0079] According to an embodiment, at least one of the blanking steps is annular crown blanking.

[0080] According to an embodiment, at least one of the punching steps is an annular crown punching of the inner radial extension 15 for connection to a bell 16 for connection to a stub axle of the vehicle and / or to a central feed and connection part to a wheel hub 17 .

[0081] According to an embodiment, at least one of the steps of blanking is blanking of a complete disc. Simultaneously with or after the blanking, a step of drawing a central bell-shaped portion 18 for connection to a stub axle of a vehicle is provided.

[0082] According to an embodiment, a further step of stamping and / or drawing point-shaped portions or bosses 19 in the first disc-shaped portion 2 and / or the second disc-shaped portion 5 and / or the ventilation spacer 8 is provided simultaneously with or after the punching to form recessed portions and / or raised portions suitable for local welding and / or spot welding.

[0083] The term "boss" refers to a portion of local variation in shape and / or thickness of the plate 3 or 6 or the ventilation spacer 8, i.e., it can be defined as a point-shaped portion to form a small cavity between the plate 3 or the plate 6 and the ventilation spacer 8, which cavity is suitable, for example, for forming a local capacitive weld or, for example, for allowing an arc to form a weld spot. Since it can be expected that the weld spot will not directly affect the braking surface of the plate 3, 6 (i.e., the surface for cooperating with the brake pad), it is allowed that the discontinuity and / or mechanical characteristics of the geometry and / or structure of the plate 3, 6 are reduced or completely absent.

[0084] According to an embodiment, a further step of punching and / or drawing bosses 19 in the first disc-shaped part 2 and / or the second disc-shaped part 5 and / or the ventilation spacer 8 is provided simultaneously with or after the blanking, and wherein the step of manufacturing the bosses is provided at the points provided with the discontinuous welds 14. This type of welding is called projection welding.

[0085] According to an embodiment, the boss housing 34 is manufactured before, after or simultaneously with the further step of stamping and / or drawing the bosses 19 in the first disk-shaped part 2 and / or the second disk-shaped part 5 and / or the ventilation spacer 8 .

[0086] According to an embodiment, said first and second protrusions 9, 10 comprise at least some flat end portions 20, wherein a step of placing said first disc-shaped portion 2 and / or second disc-shaped portion 5 on said at least some flat end portions is provided.

[0087] According to an embodiment, said first and second protrusions 9, 10 comprise at least some flat end portions 20, wherein a step of placing said bosses 19 of said first and / or second disc-shaped portion 2, 5 on said at least some flat end portions 20 is provided.

[0088] According to an embodiment, a step of manufacturing a first passage opening 21 and / or a second passage opening 22 for a welding electrode and / or a welding stud is provided simultaneously with or separately from the aforementioned step of punching out a first disk-shaped portion 2 and / or a second disk-shaped portion in the at least one sheet.

[0089] According to an embodiment, a third channel opening 23 for welding the stud 24 is provided simultaneously with or separately from the step of punching out the third portion 7 suitable for manufacturing the ventilation spacer 8 in the at least one sheet.

[0090] According to an embodiment, said step of connecting said first disc-shaped portion 2 and / or second disc-shaped portion 5 suitable for manufacturing a first plate 3 and / or a second plate 6 to said first protrusion 9 and / or second protrusion 10 by means of discontinuous welds 14 provides a step of capacitor spot welding.

[0091] According to an embodiment, the step of connecting the first disk-shaped part 2 and / or the second disk-shaped part 5 suitable for manufacturing the first plate 3 and / or the second plate 6 to the first protrusion 9 and / or the second protrusion 10 by means of discontinuous welds 14 provides a step of welding at the boss 19 using a pair of annular electrodes or welding plates or annular welding plates 32, wherein the pair of annular electrodes or welding plates or annular welding plates 32 are suitable for resting on the plates 3, 6 and forming an electric potential difference, and are suitable for determining the spot welding of the contact portion between the plates 3, 6 and the ventilation spacer 8 at the boss 19.

[0092] According to an embodiment, the step of connecting the first disk-shaped part 2 and / or the second disk-shaped part 5 suitable for manufacturing the first plate 3 and / or the second plate 6 to the first protrusion 9 and / or the second protrusion 10 through discontinuous welds 14 provides a step of simultaneously welding with multiple welding electrodes 25, and the multiple welding electrodes simultaneously form multiple discontinuous welds 14.

[0093] According to an embodiment, a step of manufacturing a first channel opening 21 and / or a second channel opening 22 for welding electrodes 25 is provided simultaneously with or separately from the aforementioned step of punching out the first disk-shaped portion 2 and / or the second disk-shaped portion in the at least one sheet, and wherein a step of allowing at least some welding electrodes 25 to enter the first channel opening 21 and / or the second channel opening 22 for welding electrodes is provided.

[0094] According to an embodiment, the first disc-shaped portion 2 is brought close to the portion 7 forming the ventilation spacer 8 and the second disc-shaped portion 5 is brought close to the ventilation spacer 8 on the opposite side of the ventilation spacer 8 .

[0095] According to an embodiment, a further step of placing at least one first welding electrode 25 at said first disk-shaped part 2 or second disk-shaped part 5 is provided.

[0096] According to an embodiment, a step of producing a first passage opening 21 or a second passage opening 22 for a welding stud is provided simultaneously with or separately from the aforementioned step of punching out a first disk-shaped portion 2 or a second disk-shaped portion in said at least one sheet.

[0097] According to an embodiment, a first step of introducing at least one second welding electrode 25 into an electrode opening 22 , 21 provided in the second disk-shaped part 5 or the first disk-shaped part 2 and placing the ventilation spacer 8 , the second welding electrode 25 is provided.

[0098] According to an embodiment, a further step of connecting the ventilation spacer 8 to the first disc-shaped part 2 or the second disc-shaped part 5 by means of welding spots 14 is provided.

[0099] According to a preferred embodiment, the connection is welding and capacitor welding.

[0100] According to another embodiment, the following steps are provided:

[0101] - bringing the first disc-shaped portion 2 close to the portion 7 forming the ventilation spacer 8 and bringing the second disc-shaped portion 5 close to the ventilation spacer 8 on the opposite side of the ventilation spacer 8;

[0102] - providing a step of making a first passage opening 21 and a second passage opening 22 for welding the studs simultaneously with or separately from said step of punching out the first disk-shaped portion 2 and the second disk-shaped portion in said at least one sheet;

[0103] - providing, simultaneously with or separately from said step of punching out in said at least one sheet a third portion 7 suitable for making a ventilation spacer 8, a third passage opening 23 for making a welding stud 24; and

[0104] - aligning the first passage opening 21, the second passage opening 22 and the third passage opening 23; and

[0105] - inserting at least one welding stud 24 into each of said aligned openings 21 , 22 , 23 ; and

[0106] - bringing said at least one welding electrode 25 close to said assembly of the first and second disk-shaped parts 2, 5, ventilation spacers 8 and welding studs 24; and

[0107] - connecting the ventilation spacer 8 to the first disk-shaped part 2 or the second disk-shaped part 5 by means of the welding studs 24 through welds 14; and / or wherein the connection is welding and capacitor welding.

[0108] According to an embodiment, the welding stud 24 is a nail holding portion composed of three parts (a first disk-shaped portion 2 and a second disk-shaped portion 5 sandwiching a third portion 7), wherein the welding stud 24 is a nail fixed with or without interference, and the welding stud 24 is locally melted by welding to be held in place, and the welding stud 24 is welded to parts of the following: the first disk-shaped portion 2 and the second disk-shaped portion 5, and the third portion in contact with the first disk-shaped portion 2 and the second disk-shaped portion 5.

[0109] According to another embodiment, the following steps are provided:

[0110] - bringing the first disc-shaped portion 2 close to the portion 7 forming the ventilation spacer 8 and bringing the second disc-shaped portion 5 close to the ventilation spacer 8 on the opposite side of the ventilation spacer 8;

[0111] - providing a step of making a first passage opening 21 and a second passage opening 22 for welding the studs simultaneously with or separately from said step of punching out the first disk-shaped portion 2 and the second disk-shaped portion in said at least one sheet;

[0112] - inserting at least one first welding electrode 25 into the electrode opening 21 provided in the first disk-shaped part 2, and placing the ventilation spacer 8 and the second welding electrode 25;

[0113] - inserting at least one second welding electrode 25 into the electrode opening 22 provided in the second disk-shaped part 5 and placing the ventilation spacer 8 and the second welding electrode 25;

[0114] - connecting the ventilation spacer 8 to the first disc-shaped part 2 and the second disc-shaped part 5 by means of welds 14; and / or wherein the connection is welding and capacitor welding.

[0115] According to an embodiment, after said step of connection by means of weld points 14, said first disc-shaped portion 2 and said second disc-shaped portion 5 are machined, taking into account the tolerances of at least a portion of the outer surface of the ventilated brake band 4, so as to form the opposing braking surfaces 26, 27 of the first plate 3 and of the second plate 6.

[0116] According to an embodiment, a further step of drilling and machining the bell 16 at least in its surface is provided so as to adapt this surface of the bell 16 to cooperate with a supporting stub of a brake disc of a vehicle.

[0117] According to an embodiment, the machining is grinding, or fine turning or milling or similar machining, for example machining by chip removal and / or grinding.

[0118] According to an embodiment, at least one of said blanking steps is annular crown blanking to produce said second disk-shaped portion 5 .

[0119] According to another embodiment, the following steps are provided:

[0120] - at least one of the punching steps is annular crown punching to punch out the inner radial extension 15, thereby producing the second disc-shaped portion 2; and

[0121] - bringing the first disc-shaped portion 2 close to the portion 7 forming the ventilation spacer 8 and bringing the second disc-shaped portion 5 close to the ventilation spacer 8 on the opposite side of the ventilation spacer 8;

[0122] - connecting the ventilated spacer 8 to the first disc-shaped part 2 or the second disc-shaped part 5 by means of weld spots 14, thereby producing a ventilated brake band 4; and

[0123] - inserting said inner radial extension 15 into the cavity of the mould (provided by the two mould halves 31 and 32 ); and

[0124] - providing a step of co-casting a bell-shaped piece 16 which, when solidified, has its peripheral portion at least partially surrounding said inner radial extension 15 so as to connect said bell-shaped piece 16 to said ventilated brake band 4 , thereby allowing radial thermal expansion movements of said ventilated brake band 4 relative to said bell-shaped piece 16 .

[0125] The invention also relates to a disc brake 1 comprising a brake band 4 according to any of the embodiments described above.

[0126] The present invention also relates to a disc for a disc brake manufactured according to any one of the above-mentioned manufacturing methods.

[0127] The invention also relates to a vehicle comprising a brake band 4 according to any of the embodiments described above.

[0128] A person skilled in the art may make numerous changes and modifications to the above-described embodiments, or may replace the elements with other functionally equivalent elements to meet possible needs without departing from the scope of the appended claims.

[0129] Furthermore, the invention relates to a system for producing a disc brake disc 1, comprising:

[0130] - at least one device for feeding at least one sheet having a predetermined thickness;

[0131] at least one station for punching out, in at least one sheet, a first disk-shaped portion 2 suitable for making a first plate 3 of a ventilated braking band 4;

[0132] the same station or a separate station for punching out, in at least one sheet, a second disk-shaped portion 5 suitable for making a second plate 6 of said ventilated braking band 4;

[0133] the same station or a separate station for punching out, in at least one sheet, a third portion 7 suitable for producing at least one ventilated spacer 8 for the ventilated braking band 4;

[0134] a station for drawing said third portion 7 by shaping first 9 and second 9 protrusions along a circular path on said third portion 7 so as to form first 11 and second 12 opposite recesses suitable for making ventilation channels 13 for said ventilated brake band 4;

[0135] - a station for connecting said first disk-shaped portion 2 suitable for making a first plate 3 to said first projection 9 by means of discrete welds 14;

[0136] the same station or a separate station for connecting said second disk-shaped portion 5 , suitable for making a second plate 6 , to said second projection 10 by means of discrete welds 14 .

[0137] According to an embodiment, a rotating support table is also included to control the angular position of at least the first disk-shaped part 2, the second disk-shaped part 5 and the inserted ventilation spacer 8 to support at least the first disk-shaped part 2, the second disk-shaped part 5 and the inserted ventilation spacer 8 so that the point to be welded is placed in position relative to at least one welding electrode 25.

[0138] According to an embodiment, a welding station with a single electrode is also included, wherein a plurality of weld points are produced by moving said assembly of the first disc-shaped part 2 , the second disc-shaped part 5 and the interposed ventilation spacer 8 .

[0139] According to an embodiment, a welding station with a shaped electrode (projection welding) is also included, wherein a dedicated electrode is provided with a plurality of welding electrode tips or portions 25, so that the entire component can be welded in a single operation.

[0140] According to an embodiment, the welding station provides for welding a section of brake band with a shaped welding electrode tool having multiple welding tips, for example by repeating the operation for multiple sections of brake band 4. For example, by moving the welding section 90° around the axis of the XX disk four times, the brake band can be completely welded using cheaper equipment.

[0141] According to an embodiment, welding can be performed by the following process steps: in a first process step, the part or second disc-shaped part 5 that will become the outer plate is welded to the third part 7 that will become the ventilation spacer 8, and then the first part 2 that will become the inner plate 3 is welded to the outer plate 6 and the third part 7. Alternatively, the first disc-shaped part 2 is close to the third disc-shaped part 7 and the second disc-shaped part 5, and the first disc-shaped part 2, the third disc-shaped part 7 and the second disc-shaped part 5 are all welded together at the same time, thereby making the brake band 4.

[0142] According to an embodiment, said third portion 7 is intended to be a ventilation spacer 8 , said third portion being made using additive manufacturing techniques and in a suitable material suitable for being welded to the first disc-shaped portion 2 and the second disc-shaped portion 5 .

[0143] Reference numerals list

[0144] 1 disc brake disc

[0145] 2 First disc-shaped part

[0146] 3. First Set

[0147] 4 Ventilated brake bands

[0148] 5 Second disc

[0149] 6 Second board

[0150] 7 Part 3

[0151] 8 Ventilation spacers

[0152] 9 First protrusion

[0153] 10 Second protrusion

[0154] 11 First recess

[0155] 12Second recess

[0156] 13 Ventilation channels

[0157] 14 Discontinuous solder joints

[0158] 15 Inner radial extension

[0159] 16 bell-shaped pieces

[0160] 17 Central feed and connection to wheel hub

[0161] 18 Central bell section

[0162] 19 convex and / or concave bosses or dot-shaped portions

[0163] 20 Flat end portion of the projection

[0164] 21 First channel opening

[0165] 22 Second channel opening

[0166] 23 Third channel opening

[0167] 24 Welding studs

[0168] 25 welding electrodes

[0169] 26 Braking Surfaces

[0170] 27 Braking surface

[0171] 28 Main extension welding tip for access to plate opening

[0172] 29 Smaller extended welding tip for access to plate contact

[0173] 30 Bell-shaped brake band connection and feeding device

[0174] 31 Half mold

[0175] 32 Half mold

[0176] 33 Annular welding plate or annular welding electrode

[0177] 34 Boss housing

[0178] XX Rotation axis

[0179] AA Axial direction

[0180] RR Radial direction

[0181] CC Tangential direction

[0182] D1 Inner belt diameter

[0183] D2 External belt diameter.

Claims

1. A method for manufacturing a disc brake disc (1), the method comprising the following steps: - providing at least one sheet having a predetermined thickness; - punching out a first disk-shaped portion (2) in at least one sheet, said first disk-shaped portion (2) being suitable for producing a first plate (3) of a ventilated brake band (4); - punching out a second disk-shaped portion (5) in at least one sheet, said second disk-shaped portion (5) being suitable for producing a second plate (6) of said ventilated brake band (4); - punching out a third portion (7) in at least one sheet, said third portion (7) being suitable for producing at least one ventilation spacer (8) for said ventilated brake band (4); - drawing the third portion (7) by shaping a first protrusion (9) and a second protrusion (10) along a circular path on the third portion (7) so as to form first opposite recesses (11) and second recesses (12), the first recesses (11) and the second recesses (12) being suitable for producing a ventilation channel (13) for the ventilated brake band (4), wherein the first protrusion (9) and the second protrusion (10) comprise at least some flat end portions (20); The method is characterized in that: - while punching out the first disk-shaped part (2) and / or the second disk-shaped part (5), or after punching out the first disk-shaped part (2) and / or the second disk-shaped part (5), providing the following additional step: punching and / or drawing point-shaped parts or bosses (19) in the first disk-shaped part (2) and / or the second disk-shaped part (5) to form recessed parts and / or raised parts suitable for local welding; - placing the first disk-shaped portion (2) and / or the second disk-shaped portion (5) on the at least some of the flat end portions (20) so that the bosses (19) of the first disk-shaped portion (2) and / or the second disk-shaped portion (5) are placed on the at least some of the flat end portions (20); - connecting said first disc-shaped portion (2) suitable for manufacturing a first plate (3) to said first projection (9) by means of discontinuous welds (14) at said bosses (19); - connecting said second disc-shaped portion (5) suitable for making a second plate (6) to said second projection (10) by means of discontinuous welds (14) at said bosses (19).

2. The method according to claim 1, wherein: - At least one sheet is made of a steel suitable for brake disc applications.

3. The method according to claim 1, wherein: The at least one sheet is made of a stainless steel suitable for brake disc applications.

4. The method according to any one of claims 1 to 3, wherein: A bell-shaped piece (16) is provided in association with the ventilated brake band (4), and wherein the bell-shaped piece is made of a material different from the material from which the ventilated brake band (4) is made.

5. The method according to claim 4, wherein: The bell is made of aluminum.

6. The method according to claim 1 or 2, wherein: - At least one of the punching steps is annular crown punching.

7. The method according to claim 1 or 2, wherein: - at least one of the punching steps is an annular crown punching out of an inner radial extension (15) for connection to a bell (16) for connection to a stub axle of the vehicle and / or to a central feed and connection part connected to a wheel hub (17); and / or wherein - at least one of the steps of blanking is blanking a complete disc, and wherein - Simultaneously with or after said blanking, there is provided a step of drawing a central bell-shaped portion (18) for connection to a stub axle of a vehicle.

8. The method according to any one of claims 1 to 3, wherein: - simultaneously with or separately from the step of punching out the first disk-shaped portion (2) and / or the second disk-shaped portion in the at least one sheet, a step of producing a first passage opening (21) and / or a second passage opening (22) for a welding electrode and / or a welding stud is provided.

9. The method according to any one of claims 1 to 3, wherein: - the step of connecting the first disc-shaped portion (2) suitable for making a first plate (3) to the first protrusion (9) and / or the step of connecting the second disc-shaped portion (5) suitable for making a second plate (6) to the second protrusion (10) by means of discontinuous weld spots (14) provides a step of capacitor spot welding; and / or wherein - the step of connecting the first disk-shaped part (2) suitable for manufacturing the first plate (3) to the first protrusion (9) and / or the step of connecting the second disk-shaped part (5) suitable for manufacturing the second plate (6) to the second protrusion (10) by means of discontinuous welds (14) provides a step of welding simultaneously using a plurality of welding electrodes (25), a plurality of said welding electrodes (25) simultaneously forming a plurality of said discontinuous welds (14), and wherein simultaneously with the step of punching out the first disk-shaped part (2) and / or the second disk-shaped part in the at least one sheet, or separately from the step of punching out the first disk-shaped part (2) and / or the second disk-shaped part in the at least one sheet, a step of making a first passage opening (21) and / or a second passage opening (22) for the welding electrodes (25) is provided; and wherein a step of allowing at least some of the welding electrodes (25) to enter through the first passage opening (21) and / or the second passage opening (22) for the welding electrodes is provided; or among them, The step of connecting the first disk-shaped part (2) suitable for manufacturing the first plate (3) to the first protrusion (9) and / or connecting the second disk-shaped part (5) suitable for manufacturing the second plate (6) to the second protrusion (10) by means of discontinuous weld spots (14) provides a step of welding with a pair of annular electrodes or welding plates (32), which are suitable for resting on the first plate (3) or the second plate (6) and forming an electric potential difference, and are suitable for determining spot welds in the contact portion between the first plate (3) or the second plate (6) and the ventilation spacer (8) at the boss (19).

10. The method according to any one of claims 1 to 3, wherein: - the first disc-shaped portion (2) is close to the third portion (7) forming the ventilation spacer (8) and the second disc-shaped portion (5) is close to the ventilation spacer (8) on the opposite side of the ventilation spacer (8); and / or wherein - placing at least one first welding electrode on the first disk-shaped part (2) or the second disk-shaped part (5); and / or wherein - simultaneously with or separately from the step of punching out the first disk-shaped portion (2) or the second disk-shaped portion in the at least one sheet, a step of producing a first passage opening (21) or a second passage opening (22) for the welding stud is provided; and / or among them - inserting at least one second welding electrode into a second passage opening (22) provided in the second disk-shaped part (5) or a first passage opening (21) in the first disk-shaped part (2), and placing the ventilation spacer (8), the second welding electrode; and / or wherein - connecting the ventilation spacer (8) to the first disc-shaped part (2) or the second disc-shaped part (5) by means of discontinuous welds (14); and wherein the connection is welding.

11. The method according to any one of claims 1 to 3, wherein: - the first disc-shaped portion (2) is close to the third portion (7) forming the ventilation spacer (8), and the second disc-shaped portion (5) is close to the ventilation spacer (8) on the opposite side of the ventilation spacer (8); and / or wherein - simultaneously with or separately from said step of punching out the first disk-shaped portion (2) and the second disk-shaped portion in said at least one sheet, a step of producing a first passage opening (21) and a second passage opening (22) for welding the stud is provided; and / or among them - inserting at least one first welding electrode into a first passage opening (21) provided in the first disk-shaped part (2) and placing the ventilation spacer (8), the first welding electrode; and / or wherein - inserting at least one second welding electrode into a second passage opening (22) provided in the second disk-shaped part (5) and placing the ventilation spacer (8), the second welding electrode; and / or wherein - the ventilation spacer (8) is connected to the first disc-shaped part (2) and the second disc-shaped part (5) by discontinuous welds (14); and the connection is welding.

12. The method according to any one of claims 1 to 3, wherein: - After said step of connection by discontinuous welds (14), said first disc-shaped portion (2) and said second disc-shaped portion (5) are machined, taking into account the permissible deviations of at least a portion of the outer surface of the ventilated brake band (4), so as to form the opposing braking surfaces (26, 27) of the first plate (3) and of the second plate (6).

13. The method of claim 4, wherein: - providing a further step of drilling and machining said bell (16) at least in its surface suitable for cooperating with a supporting stub of a brake disc of a vehicle.

14. The method according to any one of claims 1 to 3, wherein: - At least one of the punching steps is annular crown punching, thereby producing the second disc-shaped portion (5).

15. The method according to any one of claims 1 to 3, wherein: - at least one of the punching steps is an annular crown punching which punches out an inner radial extension (15), thereby producing the second disc-shaped portion (5); and wherein - the first disc-shaped portion (2) is close to the third portion (7) forming the ventilation spacer (8), and the second disc-shaped portion (5) is close to the ventilation spacer (8) on the opposite side of the ventilation spacer (8); and wherein - the ventilated spacer (8) is connected to the first disc-shaped part (2) or the second disc-shaped part (5) by means of discontinuous welds (14), thereby producing a ventilated brake band (4); and wherein - inserting the inner radial extension (15) into the cavity of the mould (31, 32); and wherein - providing a step of co-molding a bell-shaped piece (16) which, when solidified, at least partially surrounds the inner radial extension (15) by a peripheral portion of the bell-shaped piece (16) so as to connect the bell-shaped piece (16) to the ventilated brake band (4) and thereby allow radial thermal expansion movement of the ventilated brake band (4) relative to the bell-shaped piece (16).

16. A disc brake disc manufactured according to the method according to any one of claims 1 to 15.

17. A system for manufacturing a disc brake disc (1), the system comprising: - at least one device for feeding at least one sheet having a predetermined thickness; - at least one station for punching out a first disk-shaped portion (2) in at least one sheet, the first disk-shaped portion (2) being suitable for producing a first plate (3) of a ventilated brake band (4), wherein the first disk-shaped portion (2) is punched and / or drawn with points or bosses (19); - the same station or a separate station for punching out, in at least one sheet, a second disk-shaped portion (5) suitable for producing a second plate (6) of the ventilated brake band (4), wherein the second disk-shaped portion (5) is punched and / or drawn with points or bosses (19); the same station or another separate station for punching out a third portion (7) in at least one sheet, said third portion (7) being suitable for producing at least one ventilation spacer (8) for a ventilated brake band (4); - a station for drawing the third portion (7) by shaping a first protrusion (9) and a second protrusion (10) along a circular path on the third portion (7) so as to form first opposite recesses (11) and second recesses (12), the first recesses (11) and the second recesses (12) being suitable for producing ventilation channels (13) for the ventilated brake band (4), wherein the first protrusions (9) and the second protrusions (10) comprise at least some flat end portions (20), and wherein the first disc-shaped portion (2) and / or the second disc-shaped portion (5) are placed on the at least some flat end portions so that the bosses (19) of the first disc-shaped portion (2) and / or the second disc-shaped portion (5) are placed on the at least some flat end portions (20); - a station for connecting said first disc-shaped portion (2) suitable for making a first plate (3) to said first projection (9) by means of discontinuous welds (14); - the same station or a separate station for connecting said second disc-shaped portion (5) suitable for making a second plate (6) to said second projection (10) by means of discrete weld points (14).

18. The system of claim 17, wherein: - also comprising a rotating support table for controlling the angular position of at least the first disk-shaped part (2), the second disk-shaped part (5) and the inserted ventilation spacer (8), thereby supporting at least the first disk-shaped part (2), the second disk-shaped part (5) and the inserted ventilation spacer (8) so that the point to be welded is placed in position relative to at least one welding electrode (25); and / or among them - also comprising a welding station with a single electrode, wherein a plurality of weld points are produced by moving the assembly of the first disk-shaped part (2), the second disk-shaped part (5) and the interposed ventilation spacer (8); and / or where - Also included are welding stations with shaped electrodes, wherein a dedicated electrode is provided with multiple welding electrode tips or portions, such that the entire component can be welded in a single operation.

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