Patent Publication Number: US-2023140277-A1

Title: Bicycle braking device

Description:
BACKGROUND OF THE INVENTION 
     1. Fields of the Invention 
     The present invention relates to a bicycle braking device, and more particularly, to a bicycle braking device that reinforces the clamping force to the brake disk and enhances braking stability. 
     2. Descriptions of Related Art 
     The conventional mechanical bicycle braking device known to applicant is disclosed in Taiwanese Patent Publication No. 201928226, which is connected with a brake cable, and includes a cylinder, a piston, a plurality of beads, two linings control components. The rotation of each lining control component drives the operation part to move axially in the assembly hole of each threaded ring. Each operation part is spirally movable by cooperation with the beads and positioning holes to further move the linings to clamp the brake disk. The beads reinforce the clamping force of the linings. 
     However, the above-mentioned braking system has a disadvantage, which lies in that the position and direction of each groove for accommodating the beads in the operation part is a spiral arrangement from top to bottom, and due to the pivoting direction of the shaft, such that as long as the instantaneous pivoting force of the axis is large, the beads may jump out and enter into the adjacent groove. Therefore, the operation part cannot move precisely to produce the best clamping force. In addition, please refer to Korean Patent 10-0999381 for “Disk Brake Parking Brake Device”, mainly to focus on reducing manufacture cost of the brake disk and parking brake device. The finger part and the pad are in close contact with two sides of the magnetic disk. The brake caliper includes a cylinder whose piston moves the pad toward the brake disk hydraulically or mechanically. 
     In the parking brake device of the disk brake, there is a cam device for converting the linear motion to the rear end of the cylinder. The cam device includes a slider and a cam shaft. The slider has a hollow area formed between the slider and the circumferential surface so as to accommodate one or more guide shafts. There is at least one guide groove formed in the outer circumferential surface of the cam shaft. The guide shaft is engaged with the guide groove. 
     The slider includes the grooves that are defined through the slider, however, the grooves weaken the structural strength of the slider. 
     The present invention intends to provide a bicycle braking device to eliminate the shortcomings mentioned above. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a bicycle braking device and comprises a caliper having a gap formed between two side parts thereof. Each of the two side parts includes a threaded hole which communicates with the gap. Two operation units are respectively installed to the two threaded holes, and each operation unit includes an operation assembly and a ring. Each operation assembly has a protrusion protruding beyond the threaded hole and the outside of the caliper corresponding thereto. Each of the operation assemblies includes multiple curve slots which are located in the threaded hole corresponding thereto. The curve slots are spaced from each other and each curve slot have multiple balls partially and rotatably accommodated therein. 
     Two links each have the first end thereof connected to the protrusion of the operation assembly corresponding thereto. Each of the rings includes multiple spiral grooves formed to the inner periphery thereof. The spiral grooves are not in communication with each other. The multiple balls are partially accommodated in the spiral grooves. The rings are axially movable relative to the operation assembly. 
     Two linings are respectively connected to the two side parts of the caliper and located within the gap. When the rings move axially relative to the operation assembly and toward the gap, the two linings move and clamp the brake disk located between the two linings. 
     The two operation assemblies are rotated when the two links are respectively pivoted about the protrusions of the operation assemblies. The balls are rotated in the curve slots so that the rings are axially moved and protrude into the gap to move the two linings to clamp the brake disk. The two rings are moved into the threaded holes when the two links are pivoted reversely, the two linings remove from the brake disk. 
     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. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view to show the bicycle braking device of the present invention; 
         FIG.  2    is an exploded view of the bicycle braking device of the present invention; 
         FIG.  3    shows the core part, the sleeve and the ring; 
         FIG.  4    is a perspective view to show the ring with the spiral grooves of the bicycle braking device of the present invention; 
         FIG.  5    is a cross sectional view, taken along line V-V in  FIG.  1   ; 
         FIG.  6    shows that the bicycle braking device of the present invention and the brake disk; 
         FIG.  7    is a cross sectional view, taken along line VII-VII in  FIG.  7   , and 
         FIG.  8    shows that the two rings move axially to move the two linings to clamp the brake disk. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS.  1  to  8   , the bicycle braking device of the present invention comprises a caliper  1  which has a gap  11  formed between two side parts thereof, and each of the two side parts includes a threaded hole  12  which communicates with the gap  11 . Two operation units  2  are respectively threaded to the two threaded holes  12 . Each operation unit  2  includes an operation assembly  21  and a ring  22 . Each operation assembly  21  includes a protrusion protruding beyond the threaded hole  12  and the outside of the caliper  1  corresponding thereto. Each of the operation assemblies  21  includes multiple curve slots  23  which are located within the threaded hole  12  corresponding thereto. The curve slots  23  are spaced from each other and each curve slot  23  has multiple balls  4  partially and rotatably accommodated therein. In this embodiment, three balls  4  are located in each curve slot  23  and do not drop off from the curve slot  23 . Two links  3  each have the first end thereof connected to the protrusion of the operation assembly  21  corresponding thereto. Each of the rings  22  includes multiple spiral grooves  221  formed to the inner periphery thereof, wherein the spiral grooves  221  are not in communication with each other. The multiple balls  4  are partially accommodated in the spiral grooves  221 . The ring  22  is axially movable relative to the operation assembly  21 . Two linings  5  are respectively connected to the two side parts of the caliper  1  and located within the gap  11 . When the rings  22  move axially relative to the operation assembly  21  and toward the gap  11 , the two linings  5  move and clamp a brake disk  10  located between the two linings  5 . The two operation assemblies  21  are rotated when the two links  3  are respectively pivoted about the protrusions of the operation assemblies  21  corresponding thereto. The balls  4  are rotated in the curve slots  23  and the spiral grooves  221  so that the rings  22  are axially moved and protrude into the gap  11  to move the two linings  5  to clamp the brake disk  10 . On the contrary, when the two links are pivoted reversely, the two rings  22  are moved into the threaded holes  12 , and the two linings  5  remove from the brake disk  10 . 
     When riding the bicycle along a down-slop road or a rugged road, the rider generally reduces the speed by braking the bicycle. One of the two links  3  has the second end thereof connected to a brake cable  20  which extends toward and is connected to another one of the two links  3  so that the brake cable  20  pivots the two links  3  simultaneously as shown in  FIGS.  6  to  8   . 
     As shown in  FIGS.  3  to  7   , each of the operation assemblies  21  includes a core part  211  and a sleeve  212  which is threadedly connected to the threaded hole  12  of the link  3  corresponding thereto. Each sleeve  212  has a mount hole  213  defined axially therethrough. Each of the core parts  211  is partially accommodated in the mount hole  213  corresponding thereto. Each core part  211  has the protrusion protruding from one side thereof and the protrusion protrudes beyond the sleeve  212 . The protrusion of each core part  211  has a toothed portion  214  formed axially in the outer periphery thereof. The curve slots  23  are formed to the outer periphery of each of the core parts  211 . The toothed portion  214  of each core part  211  is engaged with a hole in the first end of the link  3  corresponding thereto, so that when the link  3  is pivoted, the core part  211  is rotated. A room  24  is formed between the inner periphery of the mount hole  213  of the sleeve  212  and the outer periphery of the core part  211  of each operation assembly  21 . The ring  22  is movably located in the room  24 . 
     As shown in  FIG.  1   , the caliper  1  includes two lugs  13  between which the gap  11  is located. A bolt  6  extends through the two lugs  13  and the two linings  5  to position the two linings  5  in the gap  11  so that the two linings  5  are secured to the caliper  1  and located in the gap  11  to as to clamp the brake disk  10 . 
     When the two operation assemblies  21  rotate by pulling the brake levers (not shown), the two links  3  are pivoted simultaneously by pulling the brake cable  20 , and the balls  4  rolls in the curve slots  23  of the core part  211  and the spiral grooves  221  of the ring  22 , so that the rings  22  are driven by the balls  4  and spirally and axially move into the gap  11  to move the two linings  5  to clamp brake disk  10  to reduce the bicycle speed. On the contrary, when releasing the brake levers (not shown), the two links  3  are pivoted reversely, the two rings  22  are moved into the threaded holes  12 , and the two linings  5  remove from the brake disk  10 . The linings  5  of the present invention are moved by the rings  22  and therefore firmly clamp the brake disk  10 . In addition, the balls  4  in the curve slots  23  and the spiral grooves  221  make the movement of the rings  22  smoothly to precisely clamp the brake disk  10 . 
     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.