PAD FOR A BICYCLE DISC BRAKE AND BICYCLE DISC BRAKE ASSEMBLY COMPRISING SUCH A PAD
20180362112 ยท 2018-12-20
Assignee
Inventors
Cpc classification
F16D65/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B62L1/005
PERFORMING OPERATIONS; TRANSPORTING
F16D55/22
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16D2065/789
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16D65/847
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B60T5/00
PERFORMING OPERATIONS; TRANSPORTING
International classification
F16D65/847
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
A bicycle brake pad of friction-wearing material that has at least one heat-dissipating element associated with the friction-wearing material.
Claims
1. A pad for a bicycle disc brake, comprising a support frame, an element made of friction-wearing material associated with a first portion of said support frame and at least one heat-dissipating element associated with said support frame, wherein at least one portion of said at least one heat-dissipating element is associated with said first portion of said support frame.
2. The pad according to claim 1, wherein said at least one portion of said at least one heat-dissipating element is in direct contact with said element made of friction-wearing material.
3. The pad according to claim 1, wherein said element made of friction-wearing material is associated with a first face of said first portion of said support frame and wherein said at least one portion of said at least one heat-dissipating element is associated with said first face.
4. The pad according to claim 1, wherein said element made of friction-wearing material is associated with a first face of said first portion of said support frame and wherein said at least one portion of said at least one heat-dissipating element is associated with a second face of said first portion of said support frame opposite to said first face.
5. The pad according to claim 1, wherein said at least one heat-dissipating element is associated with a second portion of said support frame adjacent to said first portion of said support frame.
6. The pad according to claim 5, wherein said at least one heat-dissipating element is housed in at least one seat formed on said second portion of said support frame.
7. The pad according to claim 5, wherein said second portion of said support frame comprises a through-opening for mounting the pad on a brake caliper, wherein said at least one seat is arranged between said through-opening and said first portion of said support frame.
8. The pad according to claim 5, wherein said second portion of said support frame comprises a through-opening for mounting the pad on a brake caliper, wherein said through-opening is arranged between said at least one seat and said first portion of said support frame.
9. The pad according to claim 5, comprising a first heat-dissipating element housed in a first seat formed on said second portion of said support frame between a through-opening for mounting the pad on a brake caliper and said first portion of said support frame, and a second heat-dissipating element housed in a second seat formed on said second portion of said support frame on an opposite side to said first seat with respect to said through-opening.
10. The pad according to claim 5, wherein said second portion of said support frame has a predetermined thickness, wherein said at least one heat-dissipating element has an overall thickness lower than, or equal to, said predetermined thickness.
11. The pad according to claim 10, wherein said first portion of said support frame has a thickness lower than said predetermined thickness.
12. The pad according to claim 1, wherein said at least one heat-dissipating element comprises a central main portion and opposite end portions, wherein at least one of said opposite end portions is associated with said first portion of said support frame and defines said at least one portion of said at least one heat-dissipating element.
13. The pad according to claim 12, wherein said central main portion is housed in said at least one seat.
14. The pad according to claim 12, wherein said at least one heat-dissipating element comprises a wire-like element, wherein said central main portion of said at least one heat-dissipating element comprises a helical winding of said wire-like element having a circular or square geometry, wherein said at least one of said opposite end portions of said at least one heat-dissipating element comprises a rectilinear portion of said wire-like element.
15. The pad according to claim 14, wherein said wire-like element has a circular or square section.
16. The pad according to claim 1, wherein said support frame is made of aluminum and said at least one heat-dissipating element is made of a material having a coefficient of thermal conductivity greater than that of aluminum.
17. A bicycle disc brake assembly, comprising at least one pair of pads according to claim 1 at least partially housed in a brake caliper.
18. The bicycle disc brake assembly according to claim 17, wherein said at least one heat-dissipating element is at least partially arranged outside of said brake caliper.
19. A brake caliper for a bicycle disc brake, comprising a main body having a slot for housing at least one pair of pads, wherein said main body comprises at least one heat-dissipating element.
20. The brake caliper according to claim 19, wherein said at least one heat-dissipating element is arranged at said slot.
21. The brake caliper according to claim 20, wherein said brake caliper comprises at least one first heat-dissipating element arranged at a first side of said slot and at least one second heat-dissipating element arranged at a second side of said slot opposite to said first side.
22. The brake caliper according to claim 19, wherein said at least one heat-dissipating element comprises a plurality of fins, wherein the fins of said plurality of fins are preferably all parallel to one another.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The features and advantages of the invention will become clearer from the description of preferred embodiments thereof, made with reference to the attached drawings, wherein:
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0045] In a first embodiment of the pad of the invention, the element made of friction-wearing material is associated with a first face of said first portion of support frame and said at least one portion of said at least one heat-dissipating element is associated with said first face.
[0046] In a second embodiment of the pad of the invention, the element made of friction-wearing material is associated with a first face of said first portion of support frame and said at least one portion of said at least one heat-dissipating element is associated with a second face of said first portion of support frame opposite to said first face.
[0047] In the preferred embodiments of the invention, said at least one heat-dissipating element is associated with a second portion of said support frame adjacent to said first portion of said support frame.
[0048] In this way the heat removed from the portion of the support frame which the brake lining is associated with is immediately transferred to a portion of support frame that is at a lower temperature, thus obtaining an effective removal of heat.
[0049] Preferably, said at least one heat-dissipating element is housed in at least one seat formed on said second portion of said support frame.
[0050] In this way the heat-dissipating element is protected and the space occupied by it is limited.
[0051] Preferably, said second portion of said support frame comprises a through-opening for mounting the pad on a brake caliper.
[0052] In some embodiments of the pad of the invention, said at least one seat is arranged between said through-opening and said first portion of said support frame.
[0053] In other embodiments of the pad of the invention, said through-opening is arranged between said at least one seat and said first portion of said support frame.
[0054] In further embodiments of the pad of the invention, the pad comprises a first heat-dissipating element housed in a first seat formed on said second portion of said support frame between said through-opening and said first portion of said support frame, and a second heat-dissipating element housed in a second seat formed on said second portion of support frame on the opposite side to said first seat with respect to said through-opening.
[0055] Preferably, said second portion of support frame has a predetermined thickness and said at least one heat-dissipating element has an overall thickness lower than, or equal to, said predetermined thickness.
[0056] In this case, advantageously, the heat-dissipating element does not project outside of the support frame.
[0057] Preferably, said first portion of said support frame has a thickness lower than said predetermined thickness.
[0058] Preferably, said at least one heat-dissipating element comprises a central main portion and opposite end portions, wherein at least one of said opposite end portions is associated with said first portion of support frame and defines said at least one portion of said at least one heat-dissipating element.
[0059] Advantageously, the end portion(s) of the heat-dissipating element transfer(s) the heat from the portion of the support frame which the brake lining is associated with to the central main portion of the heat-dissipating element.
[0060] Preferably, said central main portion is housed in said at least one seat.
[0061] Preferably, said at least one heat-dissipating element comprises a wire-like element.
[0062] More preferably, said central main portion of said at least one heat-dissipating element comprises a helical winding of said wire-like element having a circular or square geometry.
[0063] Advantageously, the use of a wire-like element wound helically makes it possible to increase the heat exchange surface.
[0064] Even more preferably, said at least one of said opposite end portions of said at least one heat-dissipating element comprises a rectilinear portion of said wire-like element.
[0065] Preferably, said wire-like element has a circular or square section. The circular section is easier to obtain than the square one, whereas the square section makes it possible to have a larger heat exchange surface.
[0066] Preferably, said support frame is made of aluminum. Such a material has good thermal conductivity and thus allows optimal removal of heat from the portion of the support frame which the brake lining is associated with.
[0067] More preferably, said at least one heat-dissipating element is made of a material having a coefficient of thermal conductivity greater than that of aluminum, so as to facilitate the removal of heat.
[0068] In a second aspect thereof, the invention relates to a bicycle disc brake assembly comprising at least one pair of pads in accordance with the present invention, wherein said pads are at least partially housed in a brake caliper.
[0069] Consequently, the bicycle disc brake assembly has all of the advantages indicated above with reference to the pad of the invention.
[0070] In some embodiments of the aforementioned assembly, said at least one heat-dissipating element is at least partially arranged outside of said brake caliper. For example, this occurs when the heat-dissipating element, or one of the heat-dissipating elements, is arranged above the through-opening for mounting the pad on the brake caliper.
[0071] In this way the heat-dissipating element is in direct contact with the air outside of the brake caliper, whereby the heat is removed quickly by means of a heat exchange by convection with air.
[0072] In a third aspect thereof, the invention relates to a brake caliper for a bicycle disc brake, comprising a main body having a slot for housing at least one pair of pads, characterized in that said main body comprises at least one heat-dissipating element.
[0073] Advantageously, the provision of a heat-dissipating element on the main body of the brake caliper makes it possible to cool the brake caliper, with consequent advantages in terms of effectiveness of braking.
[0074] Preferably, said at least one heat-dissipating element is arranged at said slot. This makes it possible to cool the brake caliper precisely at the area in which the heat is generated during braking.
[0075] More preferably, the brake caliper comprises at least one first heat-dissipating element arranged at a first side of said slot and at least one second heat-dissipating element arranged at a second side of said slot opposite to said first side.
[0076] Preferably, said at least one heat-dissipating element comprises a plurality of fins.
[0077] More preferably, the fins of said plurality of fins are all parallel to one another.
[0078] With reference now to the attached
[0079] The disc brake comprises a brake caliper 50 (
[0080] The brake caliper 50 of
[0081] What is been described hereinafter with respect to the pad 1 and to the respective disc brake is applicable identically in the case of a disc brake for a front wheel of the bicycle.
[0082] At least two opposite pads 1 in accordance with the present invention are provided inside the brake caliper 50.
[0083] The brake caliper 50 comprises a main body 52 provided with a slot 54 accessible from the outside and wherein the pads 1 are inserted. The slot 54 has a plane of symmetry substantially coinciding with a transversal mid-plane of the main body 52, which in turn coincides with the mid-plane of the brake disc.
[0084] The main body 52 illustrated in
[0085] Means for dissipating the heat generated at the pad 1 during braking are provided on the main body 52.
[0086] As illustrated in
[0087] In particular, a heat-dissipating element 56 is arranged at the slot 54 on both sides of the main body 52. A pair of heat-dissipating elements 56a, 56b arranged symmetrically on the opposite sides of the slot 54 are thus identified.
[0088] Each heat-dissipating element 56a, 56b comprises a plurality of fins 58.
[0089] Preferably, the fins 58 are parallel to one another and are arranged substantially perpendicular to the transversal mid-plane of the main body 52.
[0090] The brake disc comprises a radially outer annular portion that is arranged inside the space defined between the pads 1. By actuating an associated brake lever (not illustrated), the pads 1 are brought towards the brake disc (which rotates as a unit with the wheel of the bicycle), generating friction on the brake disc and, consequently, braking the wheel.
[0091] With reference to
[0092] The support frame 10 is made of a metallic material. Preferably, the support frame 10 is made of aluminum or alloys thereof.
[0093] The element made of friction-wearing material 20 can be made of organic materials, like for example glass fibers or copper fibers with resins, or of metallic materials, like for example sintered metallic powders.
[0094] The support frame 10 has a substantially rectangular and flattened shape.
[0095] The support frame 10 comprises a first portion 15 on which the element made of friction-wearing material 20 is associated and a second portion 11 for fastening to the brake caliper 50.
[0096] The second portion 11 of the support frame 10 is adjacent to the first portion 15 and comprises a through-opening 12 for housing a pin 13 (
[0097] As illustrated in
[0098] As shown in
[0099] The first portion 15 for supporting the element made of friction-wearing material 20 has a substantially rectangular shape, with a lower part that has a central area 15a extending downwardly.
[0100] In the present description and in the following claims the expressions upper, lower and side are used with reference to a front view of the pad as oriented in the
[0101] The element made of friction-wearing material 20 has a substantially rectangular shape. It comprises an upper surface 20a, a lower surface 20b substantially parallel to the upper surface 20a, and a pair of opposite side surfaces 20c substantially perpendicular to the upper 20a and lower surfaces 20b.
[0102] The upper surface 20a is slightly convex, whereas the lower surface 20b is slightly concave.
[0103] The element made of friction-wearing material 20 has a predetermined thickness and comprises, typically in a side end area of the upper portion thereof, a visual wear indicator 21. In particular, as illustrated in
[0104] As illustrated in
[0105] The tapering 31 is defined at the opposite joining edges of the lower surface 20b and of the side surfaces 20c of the element made of friction-wearing material 20.
[0106] Alternative embodiments of the pad 1 of the present invention are provided in which the tapering 31 is defined only at one of the opposite side end areas of the lower portion of the element made of friction-wearing material 20.
[0107] The second portion 11 of the support frame 10 has a width substantially equal to that of the first portion 15 and has a predetermined thickness. As illustrated in
[0108] The second portion 11 of the support frame 10 comprises, in addition to the through-opening 12 for mounting the pad 1 at the brake caliper 50, a seat 11b for housing heat-dissipating members of the pad 1.
[0109] Such heat-dissipating members comprise a heat-dissipating element 60 having a central main portion 62 (
[0110] As illustrated in
[0111] The seat 11b is arranged between the through-opening 12 and the first portion 15 of the support frame 10.
[0112] As illustrated in
[0113] Preferably, the heat-dissipating element 60 is made of a material having a coefficient of conductivity greater than that of the support frame 10, preferably copper or alloys thereof.
[0114] The opposite end portions 64 of the heat-dissipating element 60 each comprise a rectilinear end portion 65 that extends until it reaches the first portion 15 of the support frame 10.
[0115] Preferably, one or both of the rectilinear portions 65 of the wire-like element 61 are in direct contact with the element made of friction-wearing material 20.
[0116] In particular, one or both of the rectilinear portions 65 of the wire-like element 61 can be in direct contact with a first face 15b of the first portion 15 where the element made of friction-wearing material 20 is associated, as illustrated in
[0117] The rectilinear portions 65 of the wire-like element 61 can also be embedded in the first portion 15 of the support frame 10 or be arranged at least partially under the element made of friction-wearing material 20, as illustrated in
[0118] Alternative combinations of the aforementioned arrangements of the rectilinear portions 65 of the wire-like element 61 are also possible.
[0119] The support frame 10 also comprises a gripping handle 70 for the insertion and the extraction of the pad 1 in the brake caliper 50. In particular, the gripping handle 70 extends substantially perpendicular to the second portion 11 of the support frame 10, at the upper part 11a of the latter, on the opposite side to the element made of friction-wearing material 20.
[0120] As illustrated in
[0121] A pneumatic piston (not illustrated) is associated with the pad 1, in particular with the face 15c of the first portion 15 of the support frame 10. The pneumatic piston belongs to a pneumatic circuit of a hydraulically-controlled disc brake.
[0122] A magnetic element (not illustrated) is arranged between the pneumatic piston and the support frame 10. Such a magnetic element is fixedly associated with the pneumatic piston and coupled by magnetic attraction with the support frame 10. As an alternative to the magnetic element it is possible to use a spring.
[0123] When the brake lever is actuated, each pneumatic piston pushes the respective pad 1 against the brake disc. When the brake lever is released, each pneumatic piston goes back into its initial position and each pad 1 moves away from the brake disc by means of the magnetic attraction on the support frame 10 (which as stated is made of metallic material) exerted by the magnetic element fixedly connected to the respective pneumatic piston. Therefore, the disc brake is a hydraulically-controlled brake and the return of the pads 1 in the rest position when the brake is deactivated takes place by means of the magnetic attraction exerted by the magnetic element of the respective pneumatic piston on the support frame.
[0124] In an alternative embodiment of a hydraulically-controlled disc brake, instead of the aforementioned magnetic element a spring is used arranged between the two support frames 10 of the pads 1 of the disc brake. When the brake lever is activated, each pneumatic piston pushes the respective pad 1 against the brake disc, compressing the spring. When the brake lever is released, each pneumatic piston goes back into its initial position and each pad 1 moves away from the brake disc by means of the elastic thrust exerted by the spring.
[0125] The pad 1 described above can also be used in a manually-controlled disc brake.
[0126] A second preferred embodiment of the pad 1 of the invention is illustrated in
[0127] In this second preferred embodiment, the pad 1 is mounted in a brake caliper 50 substantially identical to that of
[0128] The pad 1 of
[0129] Once the pad 1 is mounted in the brake caliper 50 (
[0130] A third preferred embodiment of the pad 1 of the invention is illustrated in
[0131] In this third preferred embodiment, the pad 1 is mounted in a brake caliper 50 substantially identical to that of
[0132] The pad 1 of
[0133] As illustrated in
[0134] The heat-dissipating element 160 is substantially identical to the heat-dissipating element 60 of the pad 1 of
[0135] The heat-dissipating element 260, on the other hand, is substantially identical to that of the pad 1 of
[0136] As illustrated in
[0137] Preferably, the rectilinear portions 165 of the heat-dissipating element 160 are substantially parallel to the rectilinear portions 265 of the heat-dissipating element 2.
[0138] Once the pad 1 is mounted in the brake caliper 50, the central main portion 262 of the heat-dissipating element 260 is arranged, substantially entirely, outside of the main body 52 of the brake caliper 50, whereas the heat-dissipating element 160 is arranged inside the brake caliper 50.
[0139] A fourth preferred embodiment of the pad 1 of the invention is illustrated in
[0140] In this fourth preferred embodiment, the pad 1 is mounted in a brake caliper 50 substantially identical to that of
[0141] The pad 1 of
[0142] The adoption of the aforementioned heat-dissipating elements on the pad 1 and/or on the brake caliper 50 gives the possibility of evaluating the formulation of different compositions for the compounds of the element made of friction-wearing material 20, also including graphene, so as to increase the conductivity thereof. Furthermore, since the temperature of the element made of friction-wearing material is lower thanks to the removal of heat, the expansion difference between support frame 10 and element made of friction-wearing material 20 is reduced and this makes the union of the two components more stable.
[0143] The helical windings formed by the wire-like elements of the heat-dissipating elements of the pad 1 can have different pitches along the same winding.
[0144] A fifth preferred embodiment of the pad 1 of the invention is illustrated in
[0145] In this fifth preferred embodiment, the pad 1 is mounted in a brake caliper 50 substantially identical to that of
[0146] The pad 1 of
[0147] The embodiment of
[0148] The embodiments of
[0149] The Applicant has found that:
[0150] by making the heat-dissipating element 60 through a wire-like element 61 that is 25 mm in length and having a circular section with a diameter equal to 0.7 mm, such a wire-like element 61 being wound helically with a pitch equal to 1 mm to form coils having a diameter equal to 4 mm, the heat exchange surface of the pad 1 of
[0151] by making the heat-dissipating element 60 through a wire-like element 61 that is 25 mm in length and having a circular section with a diameter equal to 1.2 mm, such a wire-like element 61 being wound helically with a pitch equal to 1.5 mm to form coils having a diameter equal to 4 mm, the heat exchange surface of the pad 1 of
[0152] This confirms that, all other conditions being equal, as the diameter of the wire-like element increases, the heat exchange surface increases.
[0153] The Applicant also found that:
[0154] by making the heat-dissipating element 160 through a wire-like element 161 that is 20 mm in length and having a circular section with a diameter equal to 0.7 mm, such a wire-like element 161 being wound helically with a pitch equal to 1 mm to form coils having a diameter equal to 3 mm, and making the heat-dissipating element 260 through a wire-like element 261 that is 25 mm in length and having a circular section with a diameter equal to 1.2 mm, such a wire-like element 261 being wound helically with a pitch equal to 1.5 mm to form coils having a diameter equal to 4 mm, there would be a heat exchange surface equal to about 350 mm2 at the heat-dissipating element 160 and equal to about 700 mm2 at the heat-dissipating element 260, so that the overall heat exchange surface of the pad 1 of
[0155] by making the heat-dissipating element 160 through a wire-like element 161 that is 20 mm in length and having a square section with side of the square equal to 0.7 mm, such a wire-like element 161 being wound helically with a pitch equal to 1 mm to form coils having a diameter equal to 3 mm, and making the heat-dissipating element 260 through a wire-like element 261 that is 25 mm in length and having square section with side of the square equal to 1.2 mm, such a wire-like element 261 being wound helically with a pitch equal to 1.5 mm to form coils having a diameter equal to 4 mm, there would be a heat exchange surface equal to about 450 mm2 at the heat-dissipating element 160 and equal to about 900 mm2 at the heat-dissipating element 260, so that the overall heat exchange surface of the pad 1 of
[0156] This confirms that, all other conditions being equal, the use of a wire with a square section results in an increased heat exchange surface.
[0157] Of course, those skilled in the art can bring numerous modifications and variants to the present invention, in order to satisfy specific and contingent requirements, all of which are in any case encompassed by the scope of protection defined by the following claims.