Braking device for a rimmed wheel, particularly for a bicycle wheel

BRAKING DEVICE FOR A WHEEL RIM PARTICULAR

WHEEL BIKE

p0003The present invention relates to a braking device for a wheel rim, particularly for a bicycle wheel rim.

p0004In the cycling field, the bicycle generally comprise two wheels mounted on a frame and drive means with a pedal comprising at least one tray, at least one fixed drive pinion of the rear wheel and a drive chain between the tea and pinion, this for the vast majority.

p0005Nevertheless, significant progress has been made in the area of ​​the cycle, especially under the impact of major international events and professionals involved.

p0006In this sport, fans are very demanding and are looking for high performance materials.

p0007Thus managers have changed dramatically and we know that this is a very important part in the behavior of a bicycle. Indeed, the quality of a framework depends to a large extent the performance and restitution efforts.

p0008We must resolve a problem before linking two conflicting parameters:

p0009- Stiffness to avoid deformation and therefore energy absorption, and

p0010- The weight to be reduced in order not to penalize practicing, especially when the presence of the golf slopes or steep inclines. Thus the applicant of the present invention has been led to use composite materials incorporating carbon fibers and / or other technical fibers for the realization of frames.

p0011Components mounted on the framework are very sophisticated from the point of view of the mechanisms that the materials which constitute them.

p0012Thus the stems, handlebars, derailleur and their controls have evolved.

p0013by we see against relatively little progress in the field of brakes that are initially security features but also performance. Practitioners including competition but also advanced amateurs need braking devices with excellent performance in downhill especially when weather conditions are bad.

p0014Progress has been made on the braking interface. Thus, the annular zone of the rim is subjected to surface treatments such as a ceramization and the brake pads themselves are made of materials capable of braking even in the presence of water, gradually, and these pads may keep these performances even when there is a sharp rise in temperature.

p0015The mechanism for applying pressure to the pads on the rim remains virtually unchanged. This mechanism comprises:

p0016- An actuator lever-type operable by the practitioner, and

p0017- A transmission of the shares printed by the practitioner on the lever the cable brake means or by any other means including hydraulic fluid. These known braking means uses a pair of arms arranged on either side of the rim. Each arm is rotatably mounted on a pivot which is integral with the frame. Both arrangements are possible: - Either one of the ends of the arms carries the pad, the other end is connected to the transmission and the pivot is interposed between the two ends,

p0018- Either one of the ends of the arms is pivoted, the other end is connected to the transmission and the pad is interposed between the two ends,

p0019Traction direction exercised by the transmission are adapted so that each pad is pressed against the rim when the practitioner exerts a force on the lever with a multiplier effect. Each of the arms further comprises a biasing means such as a loop spring, usually interposed between the frame and arm so as to recall back from the rim the arm and the pad it carries after the practicing exerted action.

p0020These arrangements of the prior art have the disadvantage of requiring a pivot connection which may be mentioned several drawbacks. The friction of the swivel arms are raised, especially that there are particles projected during travel that could be introduced between the pivot and arm. This generates greater efforts to operate. In addition, there is the presence of a spring, which is an additional part, an additional weight, a problem of source by its very presence. As spring has a callback, requires that the practitioner has a first effort to cancel the recall effort which adds a second effort to curb. To ensure an effective return of the arm carrying the pad and \ / a \ NCRE potential additional friction to the right of the pivot connection generated by the mud, the return means, generally a spring, are oversized.

p0021The force exerted by the practitioner to cancel that effort during braking is increased accordingly. It is noteworthy that, on a bike, the practitioner must hold the handlebars and act with one or more fingers on the lever so that it would be attractive to the practitioner of having to carry a small force on the lever , almost equal to only effort required to operate the brake and avoid the extra effort due to oversize return means. Precise braking would be even better. It is recalled that there is no possibility of introducing braking assistance as in motor vehicles. As to the alternative of increasing the length of the arm, it must be -tempérée that the necessary race at the lever increases. Also, rather than increasing the power, it is necessary to remove static friction.

p0022Another disadvantage of the pivot connection lies also in the defects of progressivity during braking actions especially if it occurs partial seizure of the said pivot connection. These seizures are mainly due to the deterioration of materials on the surface and the progressive wear that results, particularly in areas of friction.

p0023The present invention provides a braking device which is progressive, lighter than the devices of the prior art and which removes the risk of seizing due to greater resistance to wear, to the elimination of friction in the connection pivot and implementation of said device composite material. The braking device according to the invention offers more opportunities airfoil and especially aesthetic forms. To this end, the invention relates to a braking device, intended to be mounted on a bicycle frame having at least one wheel rim, comprising a fixed support, and two rigid arms movable with respect to said fixed support, and two elastic return integral connections of said fixed support, said device is characterized in that, each arm comprising a friction member provided to cooperate with said rim at its lower end and a finger at its upper end, each arm is linked to said fixed support by the return connection elastic interposed between its upper and lower ends and said fixed support.

p0024The braking device on the rim according to the present invention, in particular for a bicycle wheel, is now described in detail according to a particular embodiment, but not limiting.

p0025This description is based on the accompanying drawings including different figures which show:

p0026- IA and Figure IB: a schematic view of a braking device according to the invention fitted to a bicycle frame according to a first embodiment of the actuating means, respectively in the rest position and braking position,

p0027- Figures 2A and 2B a schematic view of a braking device according to the invention fitted to a bicycle frame according to a second embodiment of actuating means according to the invention, respectively in the rest position and braking position,

p0028- Figure 3 is a front perspective view of a braking device according to the invention in a second embodiment of the maneuvering means in the rest position, - Figure 4 is a rear perspective view of a braking device according to the invention in a second embodiment of actuating means in the rest position.

p0029RN figures, IB, 2A and 2B, a braking device is shown according to the invention mounted on a bicycle frame C having at least one wheel R to rim 10. Figures IA and IB illustrate an example of mounting a braking device on a portion of a bicycle frame C comparable to a front fork, while figures 2A and 2B illustrate an example of mounting a brake device on a portion of a G part of assimilable bike rear stays. The braking device may be mounted on any part of a bicycle frame C located on a wheel rim R 10, whether a front fork, rear shrouds or any another part of the bicycle frame.

p0030The braking device according to the invention comprises a fixed support 12 can be attached to a bicycle frame C, two arms 146 and 14b rigid and movable relative to said fixed support 12 with two links 166 and 16b elastically restored, integral with said fixed support 12.

p0031To be attached to a bicycle frame C, said fixed holder 12 includes fixing means S to the frame Ç. Each of the arms 146 or 14b is connected to the fixed support by a link 166 or 16 D in respective elastic return, a link 16 (5 or 16D interposed between the two ends greater than 186 or less 206 or 18D and 2OD an arm 146 or 14C) and said fixed support 12.

p0032Each link 166 or 160 to elastic return permits arm movement it supports between an initial position, called the rest and its active position, called the braking.

p0033The two arms 146 and 14D are in the form of two identical elements, disposed substantially symmetrically on either side of the wheel

p0034For each arm, the plane containing the arm 146 or 14b and the plane containing the link 166 or 16b associated with elastic return are substantially perpendicular.

p0035To effect braking, each arm 146 or 14b comprises at its lower end 206 a or 20b or 226 friction member 22b provided to cooperate with the rim 10 and a finger 246 or 24b at its upper end 186 or 18b. The friction member 226 or 22D for the braking is in the form of a pad 286 or 28b attached to the bottom 206 or 2OD end of each arm 146 or 14b by any suitable means.

p0036For example and as shown in the various figures, an elongated hole is provided at the lower end 20 (5 or 20b of an arm in order to allow alignment with the portion of the rim 10 with which it must cooperate as accurately as possible.

p0037146 or an arm 14b has a thickness e, a full width | and a height h between the ends 18b or upper 186 and lower 206 or 20b.

p0038The full width | one arm is designed to be positioned substantially in the plane so the bike to fight against the drive torque generated by rotating the wheel R during braking. And the thickness e of one arm is adapted to give it sufficient rigidity during braking. The arms 146 and 14b, as the fixed support 12, are particularly hard, both in terms of bike perpendicular to this plane, and almost dimensionally stable at the level of effort exerted.

p0039As illustrated in Figures IA and IB, the braking device according to the invention includes actuating means 26 which drive the movement of the arms 14 (5 and 14b relative to the fixed support 12 including through the mobility permitted of said arm by 166 links 16b and elastic return.

p0040The fingers 246 and 146 24b and 14b of the arm part of the maneuvering means 26 of the braking device according to the invention, and this is by putting them in motion, in particular by spreading said fingers 246 and 24b, these actuating means 26 cause movement of the arms 146 and 14b between their rest position and braking position.

p0041The rest position of said arm is illustrated in Figures IA, 2A, 3 and 4, and the braking position is illustrated in Figures IB and 2B. These maneuvering means 26, detailed later in the description, serve to generate the movement of each arm 146 and 14D from its rest position to its braking position, thanks to the effort made by the practitioner and transmitted jusqu'auxdits operating means 26 by suitable transmission means known to those skilled in the wary, such a brake lever associated with a sheath and a cable or any other means. The return of a 146 or 14D arm from its braking position to its initial position of rest entirely on the restoring force of the link 166 or 16D elastic return that connects the fixed support 12. For this purpose, the links 166 and 16D elastic return interposed between the arm 146 and 14D and the fixed support 12 with a braking device according to the invention are bonds working in bending.

p0042In a preferred embodiment of the invention, the fixed support 12, the arms 146 and 14D and the connections 166 and 16b to elastic return came from manufacture in a single piece of composite material, more particularly based fibers carbon, aramide and / or glass, embedded in a resin matrix.

p0043Thus, in a braking device manufactured in a single piece of composite material, the fixed support 12 and 146 and 14D arms may be made from fibers favoring the stiffness and light weight, such as carbon fibers, while the connections 166 and 16D including the sails 306 and 3OD, can be made from fibers favoring elasticity, such as glass fibers. As shown in Figures 3 and 4, the S securing means to the frame G, in particular a threaded pin, also come of manufacture with said fixed support, said arms and said elastic return links. The fixed support 12 and the arm 146 and 14b have geometries designed to adapt to this monolithic manufacturing method of composite material and to mechanically withstand the forces generated during braking. Also, each link 166 or 16b to resilient return comprises at least one web 306 or 3OD capable of deforming by bending under the force transmitted via the gear-shift finger 246 or 24b and to allow the return position initial rest the arm 14G or 14D when said force is released. The term "sailing" at least one area likely to deform by bending, from a neutral position determined after the production, under a sustained effort between the two parts and connects it to resume its neutral initial position when said force is released.

p0044Thus, 3OG 30b or web may be thick if the material which constitutes the achieves the desired result of working in bending. 16G bond or each elastic return 16b is also constructed so as to resist the torque R suffered during braking.

p0045The arrangement of the braking device according to the invention, made of a monolithic piece of composite material, is particularly interesting because the veil 3OG or 30b can transmit the torque R exerted by the wheel during braking and sustained by the 14G or arm 14b to the fixed support 12. Thus, the torque is transmitted directly from the interface wheel / shoe S to the connection means and therefore taken up by the frame Ç. The practitioner who uses this arrangement finds a very large escalation in actions on the brake lever because all potential friction points of seizing or mechanical jamming generated by the return springs of the prior art devices are removed.

p0046Achieving 16G link or 16b to elastic return of composite material also can significantly extend the service life and maintenance the braking performance relative to the prior art devices comprising at least one pivot connection and a return spring arm. With the braking system according to the invention, the elastic restoring force needed to move the 14G and 14D arms and to restore the neutral position after a braking action is minimal so that the force exerted by the practitioner is not only progressive but almost fully booked braking allowing a very precise dosage. This is especially true as composite materials using high modulus fibers transmit faithfully the efforts. Progressivity, the power of the resilient return can be easily adjusted by the profiles, fibers, their diameters and / or their numbers, directions, Id nature of the resin constituting the matrix.

p0047Such a braking device also provides an advantage inherent in its nature, but far from negligible in the field of the cycle: the weight. In the various figures, there is shown schematically means transmitting the force T exerted by the practitioner on the maneuvering means 26 integrated with a braking device according to the invention. These T transmission means are generally in the form of a sheath inside which a cable connected at one end to a brake lever, this in known manner, and at another end to the actuating means 26 of braking device.

p0048The braking device includes receiving means 32 of said control means, including an abutment 34 integral with the fixed support 12 and on which abuts the sheath of the transmission means T. In a first embodiment, illustrated in Figures IA and IB, these actuating means 26 connected to the transmission means T, said operating means 26 include a corner 36 of substantially trapezoidal shape, the large base at the bottom, laterally provided with two guide faces 38G and 24G 38b and 24b fingers of the two arms 140 and 14b so that when traction is ensured on said corner 36 it translate vertically and causes the movement of the arms to their braking position. More specifically, the vertical translation of the wedge 36 causes the spacing of the fingers 24 (5 and 24b relative to each other, the relative movement of the arm 14G and 14b relative to the fixed support 12 with the bending of the webs 3OG and 3OD and therefore the approximation of the pads 28 (5 and 28b toward the rim 10. in a second embodiment, illustrated in figures 2A, 2B, 3 and 4, these operating means 26 connected to the transmission means T , each finger 24b or 14b or 246 of an arm 14 (5 is equipped with a roller 40 (5 or 40b rotatably mounted and said actuating means 26 comprise a wedge 36 of substantially trapezoidal shape laterally provided with two grooves 42 (5 and 42b for rolling and guiding the rollers 4OG and 40b so that when traction is ensured on said corner 36, it is translated vertically, the 4OG rollers and 40b roll in the grooves 42G and 42b and cause the spacing of these rollers 40b and 4OG, the spacing of the fingers 24g and 24b which they are bonded, the bending of 3OG sails and 30b and therefore the approximation of pads 28G and 28b to the rim. More specifically, each of the fingers 24g or 24b is equipped with a roller or 4OG 40b, mounted to rotate freely.

p0049A corner 36 is disposed in the middle part and laterally includes two 42G and groove 42b rolling and guiding each able to receive the corresponding 4OG roller or 40b. This corner 36 is of substantially trapezoidal shape, the large base at the bottom. bans the position of the arms 14G and 14b of the braking device, the wedge 36 is such that the 4OG rollers and 40b are at the top, to the small base of law, Figures 2 A, 3 and 4. This corner 36 also carries fixing means of the active component of the transmission means T, in this case a cable.

p0050Referring to FIGS ZA, 2B, 3 and 4, we can present a block of operation. When the practitioner has an action on the brake lever actuating the transmission means T, the cable pulled from the sheath held stationary by the abutment 34, provides a pull on the wedge 36, which translates vertically.

p0051Due to this movement, the rollers 4OG and 400, fixed in translation, roll in the grooves 42G and 42b of the corresponding corner 36 that moves.

p0052The width of the wedge 36 increases, causing the spacing of these rollers 40 and G

p00534OD therefore also the distance between the fingers 246 and 24D which they are attached.

p0054Fingers 24G and 24D causes the bending of 3OG and 3OD sails, the fixed support 12 remaining stationary. The arms 14G and 14D, especially their lower ends and 2OG

p00552OD, each carrying a 28G or 28D pad, approach and cause the plating of said pads 28 and 28D on the rim 10 of the wheel, thus exerting the desired braking.

p0056According to a first improvement, the two guide faces 38G and 38D of a wedge 36 or both 42G and 42D grooves of rolling a corner 36 may have curved profiles or variable inclination. Thus, the corner 36 of the maneuvering means 26 can be used to vary the ratio (the finger of an arms race) / (brake pad stroke) or ratio (stroke of the brake lever) / (finger stroke 'an arm). These variations in ratio to directly influence the behavior of the brake device and thus adapt to different practitioners.

p0057According to a second improvement, the operating means 26 may integrate the bending limitation means in particular not to exceed the acceptable deflection limit, eg if the braking device after JR wheel was removed during maintenance. Thus, as shown in Figures 2A, 2B, 3 and 4, the corner 36 may include two lumens 446 and 44D which constitute upper and lower stops of the corner, cooperating with the projecting screw heads of fixing rollers 406 and 4OD.

p0058This avoids any untimely bending beyond the plastic limit bending of connections 16G and 16D elastic return, in particular when the wheel R is removed. The braking device of the invention provides attractive features of¹ aerodynamics, compactness and lightness in the version made of composite material.

p0059The braking device according to two embodiments can be sold as original equipment but also aftermarket. The adaptation is very simple since it is enough to fix the threaded rod of S securing means on the frame C in place of the existing device.

p0060Finally, the braking device according to the invention provides significant advantages in terms of weight, braking performance, especially flexibility and progressivity, resistance to wear and even aesthetics.