Patent Application
20070137948
The present invention relates to a bicycle brake mechanism which includes links to activate the two brake pads to step the rim simultaneously.
Conventional brake systems includes disk brake system and caliper brake system. The disk brake system includes complicated mechanism and can brake the wheel sharply, the caliper brake system is economically manufactured and is suitable for stop wheels at slow speed. The disk brake system uses hydraulic oil to activate the brake action and the caliper brake system uses brake cables to pivot two brake pads to stop the wheel. The brake cable is connected to a yoke cable which has two ends respectively connected to two brake arms so that when the brake cable pulls the yoke cable, the two brake arms are pivoted and the brake pads on the two brake arms are move to stop the wheel. It is noted that the two brake pads cannot contact the rim simultaneously, in other words, one of the pads contacts the rim first so that the rim is applied by a force in one direction, and then the other brake pad contact the rim in opposite direction. Because at the beginning of the braking action, only one brake pad is in contact with the rim so that the speed of rim does not reduces as desired and the brake distance is therefore prolonged.
The present invention intends to provide a bicycle brake mechanism whose brake pads are in contact with the wheel rim simultaneously to effectively stop the wheel.
The present invention intends to provide a bicycle mechanism wherein the brake cable extends through the front fork.
The present invention relates to a bicycle brake mechanism which comprises a body located above a front wheel and a pivotable member is pivotably connected to the body and connected to a brake cable. Two brake arms are located at inside of the body and movably connected to the body by two tubes extending through two elongate holes in the body. Each brake arms has a brake pad connected thereto. The two tubes are in contact with the pivotable member so that the two brake arms are moved when the pivotable member is pivoted by pulling the brake cable. Two link units are pivotably connected to two ends of each of the brake arms and the body so that the two brake arms are moved simultaneously by the two link units.
The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.
Referring to FIGS. 1 to 7, the bicycle brake mechanism 1 of the present invention comprises a U-shaped body 10 which is located above a front wheel and a through hole 16 is defined in a top of the body 10. A connector 17 is engaged with the through hole 16 so that the brake cable “B” extends through the front fork “A”, the connector 17, and the through hole 16 and is then connected with a pivotable member 20 which will be described hereinafter. Two slots 11 are defined through a top of two ends of the body 10 and two first elongate holes 14 are defined through a side of each of the two ends of the body 10. Two plates 15 extend from two respective lower edges of the two ends of the body 10 and two connection lugs 12 extend from each of the two ends of the body 10 and located opposite to the front fork “A”. Two cushion members 18 are connected to the two ends of the body 10 so as to prevent impact with the front fork “A”.
The pivotable member 20 includes two legs 21 which movably extend through the two slots 11 and each leg 21 includes an L-shaped end. Two pins 22 extend through the two L-shaped ends and two holes 151 in the two plates 15 to pivotably connect the pivotable member 20 to the body 10. The two pins 22 each have an aperture and a spring clip “E” extends through the aperture to prevent the pin 22 from being pulled backward through the two holes 151 in the two plates 15 of the body 10. The pivotable member 20 has two top lugs 23 on a center thereof and a securing unit is connected to the two top lugs 23. The securing unit includes a tubular member 24 which extends through the two top lugs 23 and includes a recess 242 defined in an outer periphery thereof. The tubular member 24 has a groove defined in an outer periphery of an end thereof and a C-clip 241 is engaged with the groove to position the tubular member 24. A securing plate 243 is engaged with the recess 242 and a bolt 244 extends through the securing plate 243 so as secure the brake cable “B” between the securing plate 243 and the recess 242.
Two brake arms 40 are located at inside of the body 10 and movably connected to the body 10 by two tubes 42. Each of the brake arms 40 has a brake pad 41 connected thereto and the two brake pads 41 are located on two sides of the wheel rim. The two tubes 42 are located on two respective horizontal sections of the L-shaped ends of the pivotable member 20 so that the two brake arms 40 are moved when the pivotable member 20 is pivoted. Each of the brake arms 40 has two first lugs 401 extending from a first end thereof and two second lugs 402 extending from a second end thereof. The two tubes 42 are respectively connected to the second lugs 402 of the two brake arms 40 and extend through two first elongate holes 14 defined through the two ends of the body 10. Each of the tubes 42 has an end cap 42a connected to a distal end thereof to ensure that the tubes 42 will not drop from the first elongate holes 14 of the body 10.
Two link units are pivotably connected to two ends of each of the brake arms 40 and the body 10 so that the two brake arms 40 are moved simultaneously. Each of the link units includes two first links 51 and two second links 52, each of the first and second links 52 are ova plates. The first links 51 have a first end pivotably connected to the first lugs 401 of each of the two brake arms 40, a second end of the first links 51 are pivotably connected to connection lugs 12 on the body 10. The first links 52 have a first end pivotably connected to the second lugs 402 of each of the two brake arms 40, a second end of the second links 52 are pivotably connected to a through hole 13 in each of the two ends of the body 10.
A rod 53 extends through the first end of each of the first links 51 and the first lugs 401 of each of the brake arms 40 to form a first pivotable portion “C”. A bolt 56 extends through the second end of each of the first links 51, a torsion spring 54, a support tube 55 for receiving the torsion spring 54 and the connection lugs 12 of each end of the body 10 and is connected to a nut 57 so as to form a first positioning portion “D”. Another rod 53 extends through the first end of each of the second links 52, the tube 42 between the second lugs 402 and the second lugs 402 of each of the brake arms 40 to form a second pivotable portion “C1”. Another bolt 56 extends through the second end of each of the second links 52 and the through hole 13 of the body 10 and is connected with another a nut 57 so as to form a second positioning portion “D1”.
A top cap 60 is mounted on the body 10 and includes two second elongate holes 61 which are in alignment with the first elongate holes 14 of the body 10, the tubes 42 extend through the two second elongate holes 61.
Referring to
The brake cable “B” extends through the front fork “A” so that the length of the brake cable “B” that is exposed is reduced and the inherent shortcoming that the brake cable tangles objects can be effectively reduces.
While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.
