Disc for disc brake, method for making a disc for disc brake, and mounting kit

Abstract

There is described a disc for disc brake comprising a braking band (200), a bell (204), and a radial connection system for connecting the bell to the braking band. The connection system comprises at least one through-hole (210) made in an annular bell wall (206), at least one band seat (212) made in an inner annular surface (202) of the braking band (200), and at least one pin (214) at least partially inserted into the band seat (212) through the through-hole (210) of the bell wall (206) to bind the braking band (200) in rotation to the bell (204). The pin (214) is coupled to the through-hole (210) by interference and is at least partially inserted into the band seat (212) with clearance. The connection system further comprises at least one retaining formation (216) protruding from an inner surface of the annular wall (206) of the bell (204) close to the through-hole (210). The at least one retaining formation (216) is arranged to take a first non-interference condition adapted to allow the pin (214) to be inserted into the through-hole (210) and a second interference condition adapted to prevent the pin (214) from being removed from the through-hole (210). A method for making a disc for disc brake and a mounting kit for a disc for disc brake are also described.

Description

[0001] Disc for disc brake, method for making a disc for disc brake, and mounting kit

[0002] Technical field

[0003] The present invention generally applies to the field of disc brakes; in particular, the invention relates to a disc for disc brake, a method for making a disc for disc brake, and a mounting kit for disc brake.

[0004] Prior art

[0005] The embodiments of discs for disc brakes actually known involve making two parts: a braking band, on which the disc brake caliper acts to generate braking torque, and the bell, fixed to the wheel hub and associated with the braking band.

[0006] The connection between band and bell is very important because it ensures the transfer of braking torque from the band to the bell (and from the latter to the wheel hub).

[0007] Solutions are known in which the bond in rotation between band and bell is achieved by systems which include braking band teeth which couple in respective bell seats; the axial bond, on the other hand, is achieved by retainer elements capable of axially holding the teeth in the respective seats. Such embodiments are particularly simple and cost-effective.

[0008] However, they have some drawbacks, such as a particularly onerous tensional state acting on the band teeth, especially in the band ring connection zone.

[0009] In the prior art, solutions are also known for radially binding the bell in rotation to the band.

[0010] In a first example, the bell can be bound to the band by means of a threaded coupling between a fastening element and the bell.

[0011] However, such a threaded coupling has the disadvantage that the fastening element could slip off during disc operation due to vibrations. Another disadvantage is the high complexity of making the various elements due to the need to make threaded regions in the fastening element and bell.

[0012] In a further example, the bell can be bound to the band by shape coupling achieved by means of a fastening element inserted into the band and cast into the bell.

[0013] Disadvantageously, the solution which includes casting the fastening element has high assembly complexity. Furthermore, should it be necessary to separate the bell from the band, e.g., for maintenance operations, it will be necessary to break the bell so that the fastening element cast therein can be removed.

[0014] Summary of the invention

[0015] It is an object of the present invention to provide solutions for the connection between braking band and bell of a disc brake, which reduce the manufacturing and assembly complexity compared to the prior art, while simultaneously reducing the risks that the bell can uncouple from the band during the operating life of the disc brake.

[0016] It is a further object of the present invention to provide solutions for the connection between braking band and bell of a disc brake which can be used to obtain a radially-fed floating disc, in which floating of the braking band with respect to the bell is ensured without compromising the fluid dynamics of the disc, while simultaneously ensuring a stable connection between the components.

[0017] The aforesaid and other objects and advantages are achieved according to the following aspects of the invention:

[0018] - a disc for disc brake, in particular for automotive use, having the features defined in claim 1;

[0019] - a method for making a disc for disc brake, in particular for automotive use, having the features defined in claim 9; and

[0020] - a mounting kit for a disc for disc brake having the features defined in claim 10. Preferred embodiments of the invention are defined in the dependent claims, the contents of which are intended to form an integral part of the present description.

[0021] Brief description of the drawings

[0022] The functional and structural features of some preferred embodiments of a disc for disc brake, a method for making a disc for disc brake, and a mounting kit for a disc for disc brake according to the invention will now be described. Reference is made to the accompanying drawings, in which:

[0023] - figure 1 shows a perspective view of an embodiment of a disc for disc brake according to the invention;

[0024] - figure 2 shows a perspective sectional view of the disc in figure 1, seen from the cutting plane A;

[0025] - figure 3 shows a perspective sectional view of a further embodiment of a disc for disc brake according to the invention;

[0026] - figure 4 shows a perspective view of a further embodiment of a disc for disc brake according to the invention;

[0027] - figure 5 shows a perspective sectional view of the disc in figure 4, seen from the cutting plane B;

[0028] - figure 6 shows a sectional view of the disc in figure 4, seen from the cutting plane B, in which the at least one formation is in a first non-interference condition adapted to allow the pin to be inserted into the through-hole;

[0029] - figure 7 shows a sectional view of the disc in figure 4, seen from the cutting plane B, in which the at least one formation is in a second interference condition adapted to prevent the pin from being removed from the through-hole.

[0030] Detailed description

[0031] Before explaining a plurality of embodiments of the invention in detail, it is worth noting that the application of the invention is not limited to the constructional details and configuration of the components disclosed in the following description or shown in the drawings. The invention can take other embodiments and can be implemented or practiced in different manners. It should also be understood that the phraseology and the terminology are only descriptive and must not be understood as limiting. The use of "include" and "comprise" and variations thereof are intended to comprise the elements set out in the following and their equivalents, as well as additional elements and equivalents thereof.

[0032] Referring first to figure 1, a first embodiment of a disc for disc brake, in particular for automotive use, having a central axis of rotation x is described hereafter.

[0033] Furthermore, throughout the present description and in the claims, terms and expressions indicating positions and orientations, such as "longitudinal," "transverse," "vertical," or "horizontal," are to be referred to such an axis of rotation x, unless otherwise noted.

[0034] As it can be seen in figure 1 and in detail in figure 2, for example, the disc for disc brake comprises a braking band 200 intended to be engaged by a disc brake caliper to generate braking torque. The braking band 200 has an inner annular surface 202.

[0035] Furthermore, the disc for disc brake comprises a bell 204 intended to be connected to a wheel hub. The bell 204 comprises an annular bell wall 206 which extends coaxially to the central axis of rotation x.

[0036] The annular bell wall 206 is arranged radially inside the inner annular surface 202 of the braking band 200 so as to define a gap 208 therebetween.

[0037] The disc for disc brake further comprises a radial connection system for connecting the bell to the braking band.

[0038] Such a radial connection system comprises at least one through-hole 210 made in the annular bell wall 206, at least one band seat 212 made in the inner annular surface 202 of the braking band 200, facing said through-hole 210, and at least one pin 214.

[0039] The pin 214 is at least partially inserted into the band seat 212 through the through-hole 210 of the bell wall 206 according to a substantially radial direction with respect to the central axis of rotation x, in order to bind the braking band 200 in rotation with the bell 204. The pin 214 is coupled to the through-hole, and thus to the bell, by interference and is at least partially inserted into the band seat 212 with clearance.

[0040] The connection system further comprises at least one retaining formation 216 protruding from an inner surface of the annular wall 206 of the bell 204 close to the through-hole 210.

[0041] The at least one retaining formation 216 is arranged to take a first non-interference condition adapted to allow the pin 214 to be inserted into the through-hole 210 and a second interference condition adapted to prevent the pin 214 from being removed from the through- hole 210.

[0042] Referring again to figure 2, preferably, the pin 214 can have an end which comprises an abutment formation of the pin 218. The abutment formation 218 can extend radially from the lateral surface of the pin 214. The abutment formation 218 is thus adapted to pass through the through-hole 210 and abut against the inner annular surface 202 of the braking band 200.

[0043] Preferably, as it can be seen in figure 3, instead, the pin 214 can again have an end which comprises an abutment formation 218 of the pin extending radially from the lateral surface of said pin. However, such an abutment formation 218 of the pin is adapted to abut against an inner surface of the annular wall 206 of the bell 204.

[0044] Preferably, with reference to the embodiment shown in figures 4 and 5, the pin 214 can again have an end which comprises an abutment formation 218 of the pin extending radially from the lateral surface of said pin. However, such an abutment formation 218 of the pin is adapted to abut against a shoulder 220 obtained on the inner surface of the through-hole 210.

[0045] For example, as it can be seen in figures 4 and 5, the retaining formation 216 can be a single circumferential retaining formation, e.g., a collar, protruding from the inner surface of the annular wall 206 of the bell 204 and made about the through-hole 210.

[0046] Preferably, as it can be seen in figures 1 to 3, instead, the connection system can comprise a pair of retaining formations 216, 216' protruding from an inner surface of the annular wall 206 of the bell 204 close to the through-hole 210. The retaining formations 216, 216' can face each other from opposite sides of the through-hole 210 and, in the interference condition thereof, be folded onto said end of the pin 214 from opposite side of the band seat 212.

[0047] Preferably, the pair of protruding retaining formations 216, 216' can include a pair of circumferential ribs or prominences.

[0048] Preferably, the pair of circumferential ribs or prominences can be obtained by removal of material from the inner surface of the annular wall 206 of the bell 204 or plastic deformation of the material of the inner surface of the annular wall 206 of the bell 204. Preferably, the pair of circumferential ribs or prominences can be obtained by milling or similar machining.

[0049] As it can be seen in the various perspective section views of the figures, for example, the band seat 212 made in the inner annular surface 202 can have a greater depth in the radial direction than the length of a portion of the side wall of the pin intended to be accommodated in such a band seat 212.

[0050] In other words, once the pin 214 is inserted at least partially into the band seat 212 through the through-hole 210 of the bell wall 206 and is retained in the through-hole 210 and the band seat 212 by the at least one retaining formation 216, there will be an air region 222, or void, inside the band seat between one end of the pin remote from the abutment formation and a bottom wall of the band seat. Such an air region will be arranged to further accommodate the pin 314 in case of radial stresses experienced by the bell or braking band.

[0051] Furthermore, as it can be seen in figure 2, for example, a pin body diameter D 1 can be smaller than a diameter D2 of the band seat 212 so as to allow the pin to slide in the band seat in the presence of radial stresses and / or vibrations.

[0052] Preferably, the pin can be made of a material comprising steel.

[0053] Preferably, as it can be seen in figures 1 and 4, for example, the radial connection system of the bell can comprise a plurality of through-holes, band seats, pins (and a plurality of the other elements included in the radial connection system described above), arranged spaced angularly apart from one another in said annular bell wall 206.

[0054] In a further aspect, the present invention further relates to a method for making a disc for disc brake, in particular for automotive use, having a central axis of rotation x. The disc for disc brake comprises a braking band 200 intended to be engaged by a disc brake caliper to generate braking torque. Such a braking band 200 has an inner annular surface 202. The disc for disc brake further comprises a bell 204 intended to be connected to a wheel hub and comprising an annular bell wall 206 extending coaxially to the central axis of rotation x. The annular bell wall 206 is arranged radially inside the inner annular surface 202 of the braking band 200 so as to define a gap 208 therebetween.

[0055] Additionally, the disc for disc brake comprises a radial connection system for connecting the bell to the braking band. Such a connection system comprises at least one through-hole 210 made in the annular bell wall 206, at least one band seat 212 made in the inner annular surface 202 of the braking band 202, facing said through-hole 210, and at least one pin 214.

[0056] The pin 214 is at least partially inserted into the band seat 212 through the through-hole 210 of the bell wall 206 according to a substantially radial direction with respect to said central axis of rotation x, in order to bind the braking band 200 in rotation with the bell 204.

[0057] According to a preferred embodiment, the method comprises the following steps:

[0058] - making at least one retaining formation 216, 216' protruding from an inner surface of the annular wall 206 of the bell 204 close to the through-hole 210;

[0059] - introducing the pin 214, at least partially, into the band seat 212 through said through-hole 210;

[0060] - abutting the pin 210 against the inner annular surface of the braking band 206 or an inner surface of the annular wall 206 of the bell 204 or a shoulder 220 obtained on the inner surface of the through-hole 210, by means of one end of the pin on the opposite side of the band seat 212; and

[0061] - bringing the at least one formation 216, 216' from a first non-interference condition adapted to allow the pin 214 to be inserted into said through-hole 210 to a second interference condition adapted to prevent the pin 214 from being removed from the through-hole 210.

[0062] For example, figure 6 shows a section view of the disc in figure 4, seen from the cutting plane B, in which the at least one formation is in a first non-interference condition adapted to allow the pin to be inserted into the through-hole.

[0063] For example, figure 7 shows a section view of the disc in figure 4, seen from the cutting plane B, in which the at least one formation is in a second interference condition adapted to prevent the removal of the pin from the through-hole.

[0064] The depictions seen in figures 6 and 7 can similarly apply to the embodiments in figure 2 and figure 3.

[0065] In a yet further aspect, the present invention relates to a mounting kit for a disc for disc brake.

[0066] In an embodiment, the mounting kit comprises a braking band 200 intended to be engaged by a caliper of the disc brake to generate a braking torque, which has an inner annular surface 202 in which at least one band seat 212 is obtained.

[0067] The mounting kit further comprises a bell 204 intended to be connected to a wheel hub and comprising an annular bell wall 206 in which at least one through-hole 210 is made and at least one plastically deformable retaining formation 216, 216' protruding close to the through-hole 210.

[0068] Furthermore, the mounting kit comprises at least one pin 214 insertable into the band seat 212 through the through-hole 210 of the bell wall 206 to bind the braking band 200 in rotation with the bell 204.

[0069] The at least one retaining formation 216 is arranged to take a first non-interference condition adapted to allow the pin 214 to be inserted into the through-hole 210 and a second interference condition adapted to prevent the pin 214 from being removed from the through- hole 210.

[0070] All the embodiments described above for the disc for disc brake, which relate to the elements included in the mounting kit, although not repeated here, can also clearly find similar application for the elements of the mounting kit.

[0071] Thus, the advantage achieved is the provision of solutions which:

[0072] - reduce the brake disc manufacturing and assembly complexity compared to the prior art, while simultaneously reducing the risks that the bell can uncouple from the band during the operating life of the disc brake;

[0073] - can be used to obtain a radially-fed floating disc, in which floating of the braking band with respect to the bell is ensured without compromising the fluid dynamics of the disc, while simultaneously ensuring a stable connection between the components.

[0074] Various aspects and embodiments of a disc for disc brake, a method for making a disc for disc brake, and a mounting kit for a disc for disc brake according to the invention have been described. It is understood that each embodiment can be combined with any other embodiment. Furthermore, the invention is not limited to the described embodiments but may be varied within the scope defined by the appended claims.

Claims

CLAIMS1. A disc for disc brake, in particular for automotive use, having a central axis of rotation (x), comprising:- a braking band (200) intended to be engaged by a caliper of the disc brake to generate braking torque, which has an inner annular surface (202);- a bell (204) intended to be connected to a wheel hub and comprising an annular bell wall (206) extending coaxially to said central axis of rotation (x), wherein said annular bell wall (206) is arranged radially inside the inner annular surface (202) of the braking band (200) so as to define a gap (208) therebetween, and- a radial connection system for connecting the bell to the braking band, comprising at least one through-hole (210) made in said annular bell wall (206); at least one band seat (212) made in said inner annular surface (202) of the braking band (200), facing said through-hole (210); at least one pin (214) at least partially inserted into the band seat (212) through the through-hole (210) of the bell wall (206) according to a substantially radial direction with respect to said central axis of rotation (x), in order to bind the braking band (200) in rotation with the bell (204), characterized in that:- the pin (214) is coupled to the through-hole (210) by interference and is at least partially inserted into the band seat (212) with clearance;- the connection system further comprises at least one retaining formation (216) protruding from an inner surface of the annular wall (206) of the bell (204) close to the through-hole (210), wherein the at least one retaining formation (216) is arranged to take a first non-interference condition adapted to allow the pin (214) to be inserted into said through-hole (210) and a second interference condition adapted to prevent the pin (214) from being removed from the through -hole (210).

2. A disc according to claim 1, wherein said retaining formation is a circumferential retaining formation made around the through-hole 210.

3. A disc according to claim 1, wherein the connection system comprises a pair of retaining formations (216, 216') protruding from an inner surface of the annular wall (206) of the bell (204) close to the through -hole (210), facing each other from opposite sides of the through-hole (210) and, in the interference condition thereof, folded onto said end of the pin (214) from opposite side of the band seat (212).

4. A disc according to claim 3, wherein said pair of protruding retaining formations (216, 216') includes a pair of circumferential ribs or prominences.

5. A disc according to claim 4, wherein said pair of circumferential ribs or prominences is obtained by removal of material from the inner surface of the annular wall (206) of the bell (204) or plastic deformation of the material of the inner surface of the annular wall (206) of the bell (204), preferably by milling the inner surface of the annular wall (206) of the bell (204).

6. A disc according to any one of the preceding claims, wherein the pin (214) has an end comprising an abutment formation (218) of the pin extending radially from the lateral surface of said pin (214), adapted to pass through said through-hole (210) and abut against said inner annular surface (202) of the braking band (200).

7. A disc according to any one of claims 1 to 5, wherein the pin (214) has an end which comprises an abutment formation (218) of the pin extending radially from the lateral surface of said pin and adapted to abut against an inner surface of the annular wall (206) of the bell (204).

8. A disc according to any one of claims 1 to 5, wherein the pin (214) has an end which comprises an abutment formation (218) of the pin extending radially from the lateral surface of said pin and adapted to abut against a shoulder (220) obtained on the inner surface of the through-hol e (210) .

9. A method for making a disc for disc brake, in particular for automotive use, having a central axis of rotation (x), comprising:- a braking band (200) intended to be engaged by a caliper of the disc brake to generate braking torque, which has an inner annular surface (202);- a bell (204) intended to be connected to a wheel hub and comprising an annular bell wall (206) extending coaxially to said central axis of rotation (x), wherein said annular bell wall (206) is arranged radially inside the inner annular surface (202) of the braking band (200) so as to define a gap (208) therebetween, and- a radial connection system for connecting the bell to the braking band, comprising at least one through-hole (210) made in said annular bell wall (206); at least one band seat (212) made in said inner annular surface (202) of the braking band (202), facing said through-hole (210); at least one pin (214) at least partially inserted into the band seat (212) through the through-hole (210) of the bell wall (206) according to a substantially radial direction with respect to said central axis of rotation (x), in order to bind the braking band (200) in rotation with the bell (204), the method being characterized in that it comprises the following steps: making at least one formation (216, 216') protruding from an inner surface of the annular wall (206) of the bell (204) close to the through-hole (210); introducing the pin (214) at least partially into the band seat (212) through said through-hole (210), the pin (214) being at least partially inserted into the band seat (212) with clearance and coupled to said through-hole (210) by interference; abutting the pin (210) against the inner annular surface of the braking band (206) or an inner surface of the annular wall (206) of the bell (204) or a shoulder (220) obtained on the inner surface of the through-hole (210), by means of one end of the pin on the opposite side of the band seat (212); and bringing said at least one formation (216, 216') from a first non-interference condition adapted to allow the pin (214) to be inserted into said through-hole (210) to a second interference condition adapted to prevent the pin (214) from being removed from said through-hole (210).

10. A mounting kit for a disc for disc brake, comprising:- a braking band (200) intended to be engaged by a caliper of the disc brake to generatebraking torque, which has an inner annular surface (202) in which at least one band seat (212) is made;- a bell (204) intended to be connected to a wheel hub and comprising an annular bell wall (206) in which at least one through-hole (210) is made and at least one plastically deformable retaining formation (216, 216'), protruding close to the through-hole (210); and- at least one pin (214) insertable into the band seat (212) through the through-hole (210) of the bell wall (206) to bind the braking band (200) in rotation with the bell (204); wherein said at least one retaining formation (216) is arranged to take a first noninterference condition adapted to allow the pin (214) to be inserted into said through-hole (210) and a second interference condition adapted to prevent the pin (214) from being removed from said through-hole (210).

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