Caliper assembly for a disc brake

Caliper assembly for a disc brake comprising a caliper body and at least one pin; wherein said pin shank is suitable for being inserted in said at least one pin seat through said second seat opening; and wherein said pin shank comprises a first shank portion, suitable for being received in said at least one pin seat when in operative conditions, and a second shank portion, suitable for projecting canti-levered with respect to said at least one first surface, when in operative conditions; and wherein said first shank portion comprises at least one perimetric protuberance of greater extension along the transversal direction with respect to the adjacent shank portions; and wherein said at least one perimetric protuberance is suitable for forming a friction-fit between said first shank portion and said pin seat; and wherein said pin head comprises at least one under-head portion that extends from said pin head towards said pin shank to form a collar; and wherein said first shank portion comprises at least one groove, arranged between said collar and said perimetric protuberance, said groove forming a recessed shank portion, of shorter extension along the transversal direction with respect to the transversal extension of said collar and said at least one perimetric protuberance; and wherein said collar is suitable for upsetting, during the step of press-fitting said pin in said pin seat, said mouth portion of said caliper body in said groove, so as to form, through deformation of said mouth portion, a locking tooth suitable for cooperating with said groove to lock said at least one pin in said at least one pin seat.

FIELD OF THE INVENTION

The object of the present invention is a caliper assembly for a disc brake comprising a caliper body and at least one pin, as well as a pin suitable for being press-fitted in a caliper body, as well as a method for press-fitting a pin in a caliper body.

STATE OF THE ART

In a disc brake, the brake caliper is generally arranged astride of the outer peripheral margin of a brake disc, suitable for rotating about a rotation axis defining an axial direction. In a disc brake a radial direction, substantially perpendicular to said axial direction, and a tangential direction, perpendicular both to said axial direction, and to said radial direction are also defined. The brake calipers are constrained to a support structure that remains immobile with respect to the vehicle, like for example a stub axle of a suspension of a vehicle or a hub of a wheel of a vehicle. The brake caliper usually comprises a caliper body comprising two elongated portions arranged so as to face opposite braking surfaces of a brake disc, and at least one bridge that connects said two elongated portions to one another.

In a typical arrangement of a disc brake on a vehicle, a braking surface of the brake disc faces towards the vehicle, defining the vehicle side of the disc brake, and the opposite braking surface of the brake disc faces towards the wheel of the vehicle, defining the wheel side of the disc brake. Therefore, when a brake caliper is mounted on a brake disc, a first elongated portion of the caliper body is in the vehicle side, and a second elongated portion of the caliper body is in the wheel side. Friction pads are foreseen arranged between each elongated portion of the caliper body and the facing braking surfaces of the brake disc. At least one of the elongated portions of the caliper body has cylinders suitable for receiving hydraulic pistons capable of exerting a thrusting action on the friction pads abutting them against the braking surfaces of the disc to exert the braking action on the vehicle.

Pins are generally arranged beside the pads along the tangential direction of the disc brake to provide an abutment, on which the pad rests, to discharge the braking action, both in forward travel conditions and in reverse travel conditions. Pins of this type are stressed by bending. Said pins are also suitable for allowing the sliding of the friction pads towards the respective braking surfaces of the brake disc as the friction material of the brake pads is progressively consumed.

Moreover, according to a type of known brake caliper, as for example described in document EP2318729B1, the brake pads are supported by pins connected to the caliper body of the brake caliper and comprise eyelets in which canti-levered portions of said pins are inserted with clearance, so that the associated pads are free to slide along said canti-levered portions of said pins, when subjected to the action of suitable thrusting means. During the braking action, the pad is placed under traction and/or compression (for example in the case of pads for calipers for racing vehicles) and said pins have the function of transmitting the braking force that develops from the contact between pads and disc at the caliper body and therefore are stressed by bending.

Pins are generally used mounted in a caliper body suitable for guiding the relative movement of portions of the brake caliper. For example, in the technical field of floating calipers, pins are used to guide the sliding of the floating caliper body with respect to a fixed element, like for example a support bracket, as is known for example from document WO2012/156849A1.

As illustrated inFIG. 19, a known solution for a pin comprises, for example, a threaded portion that is engaged by a screw, and externally a diameter adapted to be coupled with a suitable seat formed in the caliper to ensure the coupling between pin and caliper body, in operative conditions. A pin of this type requires operation on both sides of the seat in which it is press-fit, indeed once the pin is inserted in its seat it is necessary to operate on the screw arranged on the opposite side of the side to the pin entry side. Moreover, the provision of a threaded coupling has some drawbacks. Firstly, the process of masking a hole and of threading a pin have a cost that is not always negligible with respect to the production cost of the pin, in particular considering the maintenance requirements of the machinery suitable for the purpose.

Moreover, in operating conditions, the repeated mechanical and thermal stresses deriving from the braking action, as well as the exposure to corrosive agents, or corrosion phenomena, deteriorate the threading of said coupling. Said stresses are increased when the brake caliper is designed for applications in racing vehicles, producing an increase of the undesired effects described above.

Alternative solutions to threaded coupling are generally known, for example rivets comprising a shank having variable section suitable for making a sealed coupling with the opening of a rivet seat formed in a seat body. For example, document DE102008059343A1 shows a rivet that comprises, at a shank end thereof, a portion suitable for hooking onto a surface of the seat body arranged undercut on the opposite side to the rivet entry side. When the rivet is inserted, the application of a force on said portion makes it possible to upset the seat body and to make material of the seat body flow into a groove arranged in the under-head area of the rivet.

However, a solution of this type is not suitable for being applied in brake pincers because it has some drawbacks. Firstly, the force that is generated during the entry step with interference of the rivet in the seat adds to the upsetting stresses and causes overstresses in the caliper body. Moreover, the need to operate on both sides of the seat body makes this solution very onerous in terms of the time necessary to press-fit the rivet. The shank of a rivet of this type is also unsuitable for applications as a pin for a brake caliper since it comprises a portion suitable for being bent, instead of projecting canti-levered from said caliper body.

There is therefore a need to provide a brake caliper assembly comprising at least one pin suitable for projecting canti-levered from said caliper body, as well as a method for press-fitting, coupling with force a pin in a caliper body that is quick and simple, which maintains suitable operating safety guarantees and at the same time that does not causes overstresses to the caliper body, deteriorating the mechanical properties thereof.

Solution

A purpose of the present invention is to avoid the drawbacks of the prior art and to provide a solution to the requirement of providing a caliper assembly for a disc brake, comprising at least one pin suitable for projecting canti-levered from said caliper body, capable of maintaining its mechanical characteristics over time and wherein said pin is press-fit firmly and long-lastingly at said caliper body.

A further particular purpose of the present invention is to provide a brake caliper assembly comprising at least one pin, as well as an improved method for press-fitting said pin in the caliper body, which is faster, simpler, as well as more cost-effective with respect to known solutions, without for this reason providing reduced reliability.

A further particular purpose of the present invention is that of providing a pin capable of firmly coupling in a seat formed in a caliper body, and that is lighter than known solutions.

These and other purposes are accomplished with an assembly according to claim1as well as with a method according to claim8.

Some advantageous embodiments are the object of the dependent claims.

Thanks to the provision of a caliper assembly for a disc brake comprising a caliper body and at least one pin, in accordance with the invention, a brake caliper product is provided that is reliable and suitable for maintaining its mechanical characteristics over time.

Thanks to the provision of a caliper assembly for a disc brake comprising a caliper body and at least one pin, in accordance with the invention, it is ensured that the dimensional tolerances are not changed in operating conditions, as well as ensuring that the axis of the pin is positioned geometrically where foreseen.

Thanks to the provision of a caliper assembly for a disc brake comprising a caliper body and at least one pin, suitable for being press-fitted in a pin seat by operating on a single side of the caliper body, it is possible to press-fit said pin according to a press-fitting method that is quick and simple, as well as reliable.

An assembly comprising a caliper body and at least one pin, in accordance with the present invention is lighter with respect to known solutions, thanks to the fact that said at least one pin does not need to be coupled with the caliper body through a screw or other external fixing element.

A pin in accordance with the present invention is versatile, i.e. it is capable of being used in different applications, for example and not for limiting purposes it can act as an abutment for a brake pad and/or it can act as a sliding guide for a brake pad.

DESCRIPTION OF SOME PREFERRED EMBODIMENTS

In the following description, the term “friction-fit” (in German: “Reibschluss”) between two bodies is meant to indicate a coupling by interference, in which the extent of said interference must be sufficiently high as to prevent any clearance between the two bodies coupled through friction-fit. In other words, friction-fit is the opposite to a coupling with clearance. In the description, reference will be made to the portion of pin coupled by friction-fit also as “interfering portion”.

In the following description, the term “form-friction-fit” between two bodies is meant to indicate a friction-fit, as defined above, in which at least one of said two bodies has a surface that is worked for example through knurling and/or creasing and that comprises raised parts, so that they cause elasto-plastic deformation of the surface of the other body, for example increasing the extension of the contact surface between said two bodies as well as the effectiveness of the coupling.

In the following description, the term “perimetric protuberance” is meant to indicate an offshoot, or a set of offshoots or projections, also disconnected from one another, to form an ideal path that extends at least partially along the edge of a generic section of a body and said section is not necessarily a transversal section but can be obtained through a cut in any direction.

In accordance with a general embodiment, a caliper assembly1for a disc brake comprises a caliper body2and at least one pin3.

Said caliper body2is suitable for being arranged astride of a brake disc100, said brake disc100having a first braking surface101, or vehicle-side braking surface101, and a second braking surface102, or wheel-side braking surface102, opposite said first braking surface101.

Said vehicle-side braking surface101is suitable for facing the vehicle201and said wheel-side braking surface102is suitable for facing the wheel of the vehicle202.

Said caliper body2comprises a first elongated portion41, or vehicle-side elongated portion41, suitable for facing said first braking surface101, and a second elongated portion42, or wheel-side elongated portion42, opposite said first elongated portion41and suitable for facing said second braking surface102. Said caliper body2comprises at least one bridge43that connects said first elongated portion41with said second elongated portion42so as to be arranged astride of the brake disc100, when said caliper body2is assembled to the brake disc100.

At least one from said first elongated portion41and said second elongated portion42comprises at least one first surface4, suitable for facing said first braking surface101or said second braking surface102, respectively.

In accordance with an embodiment, each of said first elongated portion41and second elongated portion42comprises said at least one first surface4, suitable for facing said first braking surface101and said second braking surface102, respectively.

At least one from said first elongated portion41and said second elongated portion42comprises at least one second surface6, opposite with respect to said first surface4and suitable for facing the vehicle or the wheel of the vehicle, respectively.

In accordance with an embodiment, each of said first elongated portion41and second elongated portion42comprises said at least one second surface6, opposite with respect to said first surface4and suitable for facing the vehicle and the wheel of the vehicle, respectively.

Said caliper body2comprises at least one pin seat7that opens into said first surface4through a first seat opening8made in said first surface4and that opens into said second surface6through a second seat opening9made in said second surface6, said pin seat7being suitable for placing said at least one first surface4in communication with said at least one second surface6.

In accordance with an embodiment, said pin seat7is a through hole, suitable for placing said first surface4in communication with said second surface6.

In accordance with an embodiment, said second surface6is arranged in a recess5of the caliper body2.

Said caliper body2comprises a mouth portion18that delimits said second seat opening9.

Said at least one pin3comprises a pin head10and a pin shank11, said pin defining a longitudinal direction X-X, coinciding with the direction of longitudinal extension of said pin shank11, and a transversal direction Y-Y, perpendicular to the longitudinal direction X-X. In the description, reference will be made to the extension along the longitudinal direction X-X also with the term “longitudinal extension”; in analogous manner, reference will be made to the extension along the transversal direction Y-Y also with the term “transversal extension”.

Said pin shank11is suitable for being inserted in said at least one pin seat7through said second seat opening9.

Said pin3is press-fitted by operating on a single side of said pin seat7of said caliper body2, and particularly from the side of said pin seat7that opens into said second surface6through said second seat opening9, and therefore it does not require operation on the side of said pin seat7of said caliper body2that opens into said first surface4through said first seat opening8. In other words, said pin3is press-fitted by operating exclusively on the outer side of said first and/or said second elongated portion41,42of the caliper body2, i.e. facing the vehicle or the wheel of the vehicle, and it does not require operation also on the inner side of said first and/or said second elongated portion41,42of the caliper body2, facing said first and/or second braking surface101,102of the brake disc100.

In accordance with an embodiment, said pin shank11is suitable for being inserted exclusively through said second seat opening9.

Said pin shank11comprises a first shank portion12, suitable for being received in said at least one pin seat7when in operative conditions, and a second shank portion22, suitable for projecting canti-levered with respect to said at least one first surface4facing said brake disc100, when in operative conditions.

Said first shank portion12comprises at least one perimetric protuberance14, of greater extension along the transversal direction Y-Y with respect to the adjacent shank portions.

Said at least one perimetric protuberance14is suitable for forming a friction-fit between said first shank portion12and said pin seat7.

The term “adjacent shank portions” is meant to indicate the portions of said pin shank11that are located close, in the specific case described above portions of said pin shank11that are close to said at least one perimetric protuberance14.

Said pin head10comprises at least one under-head portion13that extends from said pin head10towards said pin shank11, in the longitudinal direction X-X, to form a collar16.

In accordance with an embodiment, said collar has a shorter transversal extension than said pin head10and in said under-head portion13, between said collar16and said pin head10, there is an under-head step36. In accordance with an embodiment, said collar16is joined to said pin head10through an under-head slit35.

Said first shank portion12comprises at least one groove17, arranged between said collar16and said perimetric protuberance14, said groove17forming a recessed shank portion19, of shorter extension along the transversal direction Y-Y with respect to the extension along the transversal direction Y-Y of said collar16and with respect to the extension along the transversal direction Y-Y of said at least one perimetric protuberance14.

Said collar16is suitable for upsetting, during the step of press-fitting said pin3in said pin seat7, said mouth portion18of said caliper body2in said groove17, so as to form, through deformation of said mouth portion18, an locking tooth20suitable for cooperating with said groove17to lock said at least one pin3in said at least one pin seat7.

Advantageously, thanks to the provision of said collar16during the press-fitting step of said pin3, in said mouth portion18of said caliper body2, a deformation process is actuated that generates a flow of material that goes to form said locking tooth20, which when in operating conditions prevents said pin3coming out from said pin seat7. The provision of said groove17arranged between said collar16and said at least one protuberance14forces the deformed material of said mouth portion18to flow at least partially in said groove17.

Advantageously, the provision of said locking tooth20as well as of said at least one peripheral protuberance14, provides the certainty that the dimensional tolerances as well as the geometric tolerances, set at the design stage, are respected.

Advantageously, in order to press-fit said pin3in said pin seat7formed in said caliper body2, only one side of the caliper body2is operated on. In other words, said pin3can be press-fitted in said pin seat7of the caliper body2by exerting the press-fitting action exclusively on said pin head10, which is accessible from said second surface6.

In accordance with an embodiment, said locking tooth20is positioned undercut with respect to said at least one protuberance14in the longitudinal direction X-X. The provision of said locking tooth20positioned undercut with respect to said at least one protuberance14, prevents the relative movement along the longitudinal direction X-X between pin3and caliper body2.

In accordance with an embodiment, said deformation of said mouth portion18of said pin seat is an elasto-plastic deformation.

In accordance with an embodiment, said at least one perimetric protuberance14is made adjacent to said groove17, in said first shank portion12. In other words, said at least one perimetric protuberance14is made in an adjacent portion of pin shank11with respect to said groove17.

In accordance with an embodiment, the volume occupied by said collar16substantially corresponds to the volume of said groove17so that the material deformed by upsetting by said collar16and locked by said at least one protuberance14flows in said groove17, to form said locking tooth20. In other words, the volume of material of caliper body2that flows as a result of the upsetting through the action of said collar16substantially corresponds to the volume that said groove17is suitable for receiving. The material upset by the action of said collar16necessarily enters into said groove17, with the flow of material being substantially blocked by the presence of said at least one perimetric protuberance14, arranged close to said groove17. Said at least one first protuberance14is suitable both of producing a friction-fit with said pin seat7, and of influencing the flow of material upset by said collar16so that it enters into said groove17.

In accordance with an embodiment, said at least one perimetric protuberance14is knurled or worked through knurling, and is suitable for forming a form-friction-fit through a deformation of at least one portion of said pin seat7.

In accordance with an embodiment, said at least one perimetric protuberance14is worked through ribbing, and is suitable for forming a form-friction-fit through a deformation of at least one portion of said pin seat7.

The provision of at least one knurled perimetric protuberance14, during the step of press-fitting, reciprocally deforms the portion of the pin seat7with which it couples by form-friction-fit so as to counteract the relative movement between said pin3and said pin seat7, when in operating conditions.

The provision of at least one perimetric protuberance14consisting of a series of knurlings with straight teeth makes it possible to reduce the stress of the press-fitting action and increase the precision thereof, as well as constituting an anti-rotation and/or anti-translation element along the transversal direction Y-Y. Indeed, during the step of press-fitting, the valleys present in the knurling constitute actual seats where the upsetting of the material of the pin seat7moved by the knurling teeth meets up, forming an actual geometric coupling of the guide-pad type.

In accordance with an embodiment, said at least one perimetric protuberance14is at least one portion of a rounded surface of said first shank portion12, suitable for forming a friction-fit with a portion of said pin seat7.

A rounded surface has a curved profile along the longitudinal direction X-X and that varies substantially continuously, to form said at least one protuberance14, in at least one portion of maximum transversal extension thereof.

In accordance with an embodiment, said first shank portion12comprises a further perimetric protuberance14, so as to comprise at least two perimetric protuberances14a,14b.

In accordance with an embodiment, said at least two perimetric protuberances14a,14bare disconnected from one another.

Said at least two perimetric protuberances14a,14bare suitable for forming at least two portions suitable for forming a friction-fit with said pin seat7.

In accordance with an embodiment, at least one perimetric protuberance14of said at least two perimetric protuberances14a,14bis knurled or worked through knurling, and is suitable for forming a form-friction-fit through a deformation of at least one portion of said pin seat7.

In accordance with an embodiment, at least one perimetric protuberance14of said at least two perimetric protuberances14a,14bis worked through ribbing, and is suitable for forming a form-friction-fit through a deformation of at least one portion of said pin seat7.

In accordance with an embodiment, at least one perimetric protuberance14of said at least two perimetric protuberances14a,14bis at least one portion of a rounded surface of said first shank portion12, suitable for forming a friction-fit with a portion of said pin seat7.

In accordance with an embodiment, a first perimetric protuberance14bis arranged in an adjacent shank portion with respect to said groove17on the opposite side of said collar16substantially close to said second opening9and a second perimetric protuberance14ais arranged close to said first opening8of said pin seat7.

The provision of two perimetric protuberances14a,14bsubstantially close to the openings8,9of said pin seat7, makes it possible to obtain the maximum static stability of the pin3, and at the same time allows better precision of press-fitting and greater precision of geometric arrangement of the pin3in said pin seat7.

In accordance with an embodiment, exclusively said at least one perimetric protuberance14is suitable for forming a friction-fit between said first shank portion12and said pin seat7. In other words, the surfaces of said first shank portion12outside of said at least one protuberance14are unsuitable for forming a friction-fit with said pin seat7.

In accordance with an embodiment, said at least one perimetric protuberance14extends for a section along the longitudinal direction X-X that is shorter than the extension along the longitudinal direction X-X of said first shank portion12. In accordance with an embodiment, said at least one perimetric protuberance14has a shorter longitudinal extension than at least one adjacent shank portion.

The provision of at least one perimetric protuberance14on one or more parts of said first shank portion12makes it possible to friction-fit one or more parts of said first shank portion12with reciprocal portions of said pin seat7. Therefore, the provision of areas in which said first shank portion12is free from contact with said pin seat7, requires a smaller press-fitting force of said at least one pin3with respect to the press-fitting force necessary to press-fit the same pin3able to be coupled by friction-fit along the entire said first shank portion12.

In other words, the provision of an interference portion of said first shank portion12of reduced extension along the longitudinal direction with respect to the longitudinal extension of said seat makes it possible to reduce the press-fitting force of the pin, while still conserving adequate operative stability and precision of press-fitting. From an analysis carried out by the inventors, it emerges that this embodiment reduces the risk of deformation of the pin seat7, and the geometric arrangement of the pin3is more accurate with respect to a pin having a portion interfering on the entire said first shank portion12.

In accordance with an embodiment said second perimetric protuberance14bhas a shorter extension in the longitudinal direction X-X than both of the adjacent shank portions.

In accordance with an embodiment, said collar17has a greater extension in the transversal direction Y-Y than the extension in the transversal direction Y-Y of said at least one perimetric protuberance14,14a,14b. The provision of a collar16with greater transversal extension than the transversal extension of said at least one perimetric protuberance makes it possible to plasticize the material of said mouth portion18so as to form said locking tooth20.

In accordance with an embodiment, said collar16is suitable for always being press-fitted in the metal of said mouth portion18of said caliper body2, when in operating conditions.

In accordance with an embodiment, said second perimetric protuberance14bhas a shorter extension in the transversal direction Y-Y than the extension in the transversal direction Y-Y of said first perimetric protuberance14a.

The provision of a second perimetric protuberance14b, the first of the protuberances to enter into the pin seat7, with shorter transversal extension than the transversal extension of said first perimetric protuberance14a, which enters into the pin seat7after said second perimetric protuberance14b, allows both of said protuberances to make a friction-fit with said pin seat7.

In accordance with an embodiment, said second perimetric protuberance14bis knurled, and when said first shank portion12is press-fitted in said seat7, said second perimetric protuberance14bdraws said pin seat7making a drawing profile in said seat7, then said first perimetric protuberance14aof greater transversal extension with respect to said second perimetric protuberance14benters into said pin seat7and draws it again, exerting a greater interfering force on said pin seat7with respect to the interfering force exerted by said second protuberance14b, then said collar16enters that upsets the material of said mouth portion18making said locking tooth20. Therefore a second seat step34bis formed in said pin seat7by means of the interference of said second protuberance14bwith the surface of said seat wall7and a first seat step34ais formed in said pin seat7by means of the interference of the first protuberance14awith the surface of said seat wall7already drawn by said second protuberance14b.

In accordance with an embodiment, said at least one perimetric protuberance14produces said at least one seat step34.

In accordance with an embodiment, said at least one perimetric protuberance14is a single protuberance that extends along the entire said first shank portion12. In accordance with an embodiment, said single protuberance is entirely knurled.

The provision of a single perimetric protuberance that extends along the entire said first shank portion12makes it possible to maximise the force necessary to decouple said pin3from said pin seat7, as well as to maximise the anti-rotation effect of the pin shank11in the pin seat7.

In accordance with an embodiment, at least one portion of said pin shank11is substantially cylinder-shaped with a substantially circular base. In accordance with an embodiment, said under-head portion13is substantially discoid-shaped, to form said collar16. In accordance with an embodiment, said collar16is an annular collar. In accordance with an embodiment, said groove17is an annular groove. In accordance with an embodiment, said pin seat7comprises at least one substantially cylindrical wall. In accordance with an embodiment, said first seat opening8has a substantially circular shape. In accordance with an embodiment, said second seat opening9has a substantially circular shape.

The provision of a pin shank3with cylindrical geometry makes it possible to optimise the distribution of material as a function of the bending resistance value that is wished to be given to said pin shank, at the design stage.

In accordance with an embodiment, said at least one perimeter protuberance14has a substantially annular shape. In accordance with an embodiment, said rounded surface is a substantially toroidal surface.

In accordance with an embodiment, said pin head10has at least one raised portion31, made through incision of the adjacent portions of the pin head10, clinching of the pin head10, or moulding. In accordance with an embodiment, said at least one raised portion31has an ornamental function and/or one of recognition of the pin product3. In accordance with an embodiment, said at least one raised portion31is suitable for improving the grip of a tool on said pin head3.

In accordance with an embodiment, said under-head portion13comprises a toothing, suitable for causing said deformation of said mouth portion18.

In accordance with an embodiment, said pin shank11comprises a blind hole, or shank cavity21, which extends along the longitudinal direction X-X on at least one portion of said pin shank11, said shank cavity21being accessible through a cavity opening32and at least partially delimited by at least one cavity surface30.

The provision of a shank cavity21makes it possible to reduce the weight of said pin3as well as of said caliper assembly1.

In accordance with an embodiment, said pin seat7comprises at least one substantially smooth wall.

In accordance with an embodiment, at least said mouth portion18of said caliper body2is made of a tougher and/or more ductile material with respect to said pin shank11and to said collar16. In accordance with an embodiment, said pin shank11and said collar16are made of a harder material with respect to said mouth portion18of said caliper body2. In accordance with an embodiment, said caliper body2is made at least partially from aluminium or aluminium alloy or cast iron. In accordance with an embodiment, said pin3is made at least partially from steel, quenched steel or titanium.

In accordance with an embodiment, at least one from said first elongated portion41and said second elongated portion42of said caliper body2is suitable for receiving at least one brake pad15, and wherein said at least one pin3is suitable for being used as resting pin, suitable for forming an abutment for at least one abutment surface23of said at least one brake pad15. As known, during the braking action, the brake pads15abut against the braking surfaces101,102of the brake disc100, and through the tangential friction tend to follow the rotary movement of the disc100, i.e. towards the exit direction of the disc100from the caliper body2. Therefore, the use of pins3alongside said pads15makes it possible to keep the pads15in useful position, both in forward travel condition and in reverse travel condition. Said pins2can also be suitable for promoting the sliding of at least one abutment surface23of said brake pad15, when, in conditions of prolonged use, the friction material of said brake pads15is consumed by friction, forcing at least one portion of pad to approach the respective braking surface of the disc101,102, to exert the braking action.

In accordance with an embodiment, as for example illustrated inFIG. 5, each of said first elongated portion41and said second elongated portion42of said caliper body2is suitable for receiving at least one brake pad15, so that said assembly1comprises at least two brake pads15and at least four pins2, press-fitted so that said second shank portion22of each of said at least four pins3projects canti-levered substantially close to abutment surfaces23of said at least two brake pads15, so that, when in operative conditions, said at least four pins3are suitable for forming an abutment, for said at least two brake pads15.

The provision of at least one pin3suitable for forming an abutment, or a support, for at least one portion of a pad through said second shank portion22, increases the amount of stresses due to bending on said pin3, when it is in operating conditions. The provision of at least one pin3suitable for forming an abutment for a brake pad15makes it possible to make a caliper body2for example without seat pockets to receive the pads15, since the pads are kept in position by the action of said at least one pin3.

In accordance with an embodiment, said at least one pin3is suitable for being used as pad sliding pin. In other words, said second shank portion22of said pin is suitable for being inserted with clearance in an eyelet33, or a slot33, made on a brake pad15so as to form a sliding guide for the pad15, when it abuts against one of said braking surfaces101,102of the brake disc100.

In accordance with an embodiment, as for example illustrated inFIG. 6, each of said first elongated portion41and said second elongated portion42of said caliper body2is suitable for receiving at least one brake pad15, so that said assembly1comprises at least two brake pads15and at least four pins2, press-fitted so that said second shank portion22of each of said at least four pins3is inserted in a pad eyelet33of said at least two brake pads15, so that, when in operative conditions, said at least four pins3are suitable for forming a sliding guide, for said at least two brake pads15.

Said at least one pin3is versatile and can be used in different applications.

In accordance with an embodiment, said pin3is suitable for working by bending, when it is in operating conditions. In accordance with an embodiment, said pin3is suitable for working mainly by bending, when it is in operating conditions.

In accordance with an embodiment, said assembly1comprises said caliper body2and a plurality of said pins3, said plurality of said pins3being suitable for being inserted in a plurality of pin seats7, by a plurality of said second seat openings9.

The invention also concerns a pin3without caliper to be imagined as a spare part or as a supply piece for first mounting, said pin comprising a pin head10and a pin shank11. In accordance with an embodiment, said pin defines a longitudinal direction X-X, coinciding with the direction of longitudinal extension of said pin shank11, and a transversal direction Y-Y, perpendicular to the longitudinal direction X-X. In accordance with an embodiment, said pin shank11is suitable for being inserted in said at least one pin seat7through said second seat opening9. In accordance with an embodiment, said pin shank11comprises a first shank portion12, suitable for being received in said at least one pin seat7when in operative conditions, and a second shank portion22, suitable for projecting canti-levered with respect to said at least one first surface6, when in operative conditions. In accordance with an embodiment, said first shank portion12comprises at least one perimetric protuberance14, of greater extension along the transversal direction Y-Y with respect to the adjacent shank portions. In accordance with an embodiment, said at least one perimetric protuberance14is suitable for forming a friction-fit between said first shank portion12and said pin seat7. In accordance with an embodiment, said pin head10comprises at least one under-head portion13that extends from said pin head10towards said pin shank11to form a collar16. In accordance with an embodiment, said first shank portion12comprises at least one groove17, arranged between said collar16and said perimetric protuberance14, said groove17forming a recessed shank portion19, of shorter extension along the transversal direction Y-Y with respect to the extension along the transversal direction Y-Y of said collar16and to the extension along the transversal direction Y-Y of said at least one perimetric protuberance14. In accordance with an embodiment, said collar16is suitable for upsetting, during the step of press-fitting said pin3in said pin seat7, said mouth portion18of said caliper body2in said groove17, so as to form, through deformation of said mouth portion18, a locking tooth20suitable for cooperating with said groove17to lock said at least one pin3in said at least one pin seat7.

Hereinafter a method for press-fitting a pin3in a caliper body2will be described.

A method for press-fitting a pin3in a caliper body2, comprises the following steps:providing a caliper assembly1according to any one of the embodiments described above;inserting said pin shank11in said pin seat7from said second seat opening8;exerting a press-fitting action F on said pin head10, so as to deform said mouth portion18, so that it forms a locking tooth20.

The term “press-fitting action” is meant to indicate the application of a press-fitting force on said pin head10, for example a continuous pressure and/or a series of impulses of force, sufficient to press-fit said pin3in said pin seat7foreseen in said caliper body2, so as to provide friction-fit between said at least one first protuberance14and said pin seat7, as well as so as to provide for the formation of said locking tooth20by deformation of said mouth portion18.

Advantageously, the press-fitting method described above of a pin3in a caliper body2foresees to operate exclusively on one side of the caliper body2.

In accordance with a possible way of operating, a press-fitting method comprises the step of providing press-fitting equipment, which allows said two elongated bodies41,42to be connected, said press-fitting equipment comprising:

at least one press-fitting tool25, suitable for transmitting the press-fitting action F to said pin head10;at least one support element26suitable for being arranged between at least one portion of said at least one first surface4of said first elongated portion41and at least one portion of said at least one first surface4of said second elongated portion42, so as to limit, during the step of press-fitting, the deformation of said caliper body2;at least one support plane27, suitable for allowing at least one portion of at least one second surface6of at least one from said first elongated portion41and said second elongated portion42of said caliper body2to be rested, during the step of press-fitting.

Said support element26has a shape that comprises a housing surface29, suitable for at least partially receiving said second shank portion22of said pin3, when said pin3is press-fitted in said caliper body2and/or during the step of press-fitting said pin3in said caliper body2. In accordance with a possible way of operating, said housing surface29has a substantially cylindrical shape or at least one portion has a cylindrical shape.

In accordance with a possible way of operating, said support element26is made of a material suitable for resisting, for example suitable for neither twisting nor fracturing, when the press-fitting action F is exerted on said pin head10.

In accordance with a possible way of operating, said support element26comprises at least one support surface28, suitable for facing at least one portion of said first surface4of at least one from said first elongated portion41and said second elongated portion42of said caliper body2.

As illustrated inFIGS. 8 and 9, when said caliper body2is in press-fitting configuration, at least one from said first elongated portion41and said second elongated portion42projects at least partially canti-levered with respect to said bridge43. Said support element26has a shape that comprises a housing surface29, suitable for at least partially receiving said second shank portion22of said pin3, when said pin3is press-fitted in said caliper body2and/or during the step of press-fitting said pin3in said caliper body2, so as to minimise the torque able to be generated by the press-fitting action F on said pin head10, avoiding the collapse of the caliper body2under the effect of the press-fitting action F of the pin3. In other words, said support element26is suitable for transferring through it the press-fitting action to minimise the bending stresses acting on at least one from said first elongated portion41and said second elongated portion42arranged canti-levered with respect to said bridge43, when said caliper body2is in press-fitting configuration. From an analysis carried out by the inventors, it emerges that operating the press-fitting action F by using said support element26, reduces, with respect to a control piece, the tension state on at least one from said first elongated portion41and said second elongated portion42arranged canti-levered with respect to said bridge43, when said caliper body2is in press-fitting configuration, eliminating the risk of twisting of at least one portion of the caliper body2, due to the press-fitting action F.

In accordance with a possible way of operating, said housing surface29has a substantially cylindrical shape.

In accordance with a possible way of operating, a press-fitting method comprises at least one of the following further steps:inserting said support element26between said first elongated portion41and said second elongated portion42of said caliper body2;inserting said support element26between at least one portion of said at least one first surface4of said first elongated portion41and at least one portion of said at least one first surface4of said second elongated portion42;providing said pin seat7in said first elongated portion41of said caliper body2;resting said second elongated portion42on said support plane27, so as to carry out the press-fitting action F on said first elongated portion41;inserting said pin shank11in said pin seat7provided in said first elongated portion41of said caliper body2;exerting the press-fitting action on said pin head10through said press-fitting tool25;making said first and said second seat step34a,34b, in said pin seat7;minimising the torque generated by said press-fitting action F on said caliper body2;providing said pin seat7in said second elongated portion42of said caliper body2;inverting said caliper body2, i.e. rotating said caliper body by 180° so as to rest an opposite elongated portion41,42on said support plane27;resting said first elongated portion41on said support plane27, so as to carry out the press-fitting action F on said second elongated portion42;inserting said pin shank11in said pin seat7provided in said second elongated portion41of said caliper body2.

Those skilled in the art can bring numerous modifications, adaptations and replacements of elements with other functionally equivalent ones to the embodiments described above, in order to satisfy contingent and specific requirements, without however departing from the scope of the following claims.

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