Patent Publication Number: US-2007107995-A1

Title: Brake drawing system

Description:
BACKGROUND OF THE INVENTION  
      (a) Field of the Invention  
      The present invention is related to a brake drawing system applied in bikes and any motor vehicle provided with handbrake and pedal driven brake, and more particularly to one that allows easy adjustment and assured maintenance of the openness of the brake pull rod.  
      (b) Description of the Prior Art  
      Most of motorcycles or beach mobiles are engine power driven motor vehicles so they could get the greater output of kinetics to operate or by repeatedly stepping on a pair of pedals to drive both wheels for revolving at higher speed in case of a bike. In either case, a high efficiency brake system must be provided to have the wheels turning at high rpm to return to still status in the least time. Disk brake and drum brake at present are the most popular and reliable braking systems. In the disk brake, a disk or a drum is concentrically disposed at and synchronously turning with the wheel hub; and by taking advantage the fact that the liquid is prevented from compression and the Pascal&#39;s Law (states that pressure applied to a confined fluid at any point is transmitted undiminished through out the fluid in all directions and acts upon all the parts of the confined vessel at right angles to its interior surfaces and equally upon equal areas), a brake shoe is hydraulically driven to clamp on the disk to produce friction between the brake shoe and the disk or drum to stop the wheel.  
      In the entire disk brake system, the braking is achieved by having a pair of sliding calipers that push the brake shoe or the drum connected through hydraulic piping a hydraulic cylinder; and the brake pull rod pushes brake oil in the hydraulic cylinder to take advantage of hydraulic power to push the pair of calipers or a piston in the brake drum. The resultant placement by the push from the piston moves a lining for it to contact the brake disk or drum. As illustrated in  FIG. 1  of the accompanying drawings for a sectional view of a brake drawing system of the prior art, the drawing system is comprised of a hydraulic cylinder  20  fixed to a support bracket  10  and pivoted with a brake pull rod  30 . The brake pull rod  30  is coupled to a push rod  21  of the hydraulic cylinder  20  with a brake lever pin  31 . Accordingly, once the pull rod  30  swings as drawn by the user, the swing is transmitted through the brake lever pin  31  to the push rod  21 , where a piston  22  coupled to the push rod  21  pushes hydraulic oil inside the hydraulic cylinder  20  to apply the brake.  
      Whereas the motive power for a handbrake or a pedal driven brake comes from the action of the brake pull rod  30  in a brake drawing system, the openness of the brake pull rod  30  affects the action the brake pull rod  30  permits and the manipulation by the drive or the rider. Consequently, multiple teeth are provided on the push rod  21  and corresponding threaded holes are disposed on the brake lever pin  31  to constitute the coupling between the push rod  21  and the brake lever pin  31 . If necessarily, changing the relative positions between the push rod  21  and the brake lever pin  31  by turning the push rod  21  will achieve the purpose of adjusting the openness  30  of the brake pull rod  30 .  
      However, in practice, a wrench is needed to hold and turn the push rod  21  to fail immediate adjustment of the openness of the brake pull rod. It also prevents from maintaining the adjusted openness since the linearly reciprocal motion of the push rod  21  will cause it to revolve on its own axis to change the relative positions between the push rod  21  and the brake lever pin  31 , thus to change the openness of the brake push rod  21 .  
     SUMMARY OF THE INVENTION  
      The primary purpose of the present invention is to provide an improved brake drawing system that is capable of maintaining the openness of the push rod as adjusted. To achieve the purpose, an adjustment bushing is fastened to the brake lever pin for the push rod to penetrate through. Adjusting the openness of the brake pull rod by changing the relative positions between the adjustment bushing and the brake lever pin will maintain the openness of the brake pull rod as adjusted without interfering with the push rod.  
      In practice, a graded section is provided on the tail of the push rod to allow penetration by the adjustment bushing; a clip is used to clamp at where the push rod leaves the adjustment bushing to constitute the coupling between the push rod and the adjustment bushing; and a nut is disposed externally to the brake lever pin for the user to directly turn the adjustment bushing by fingers as immediate adjustment of the openness of the brake pull rod warrants. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a sectional view of a brake drawing system of the prior art.  
       FIG. 2  is a perspective view of the present invention.  
       FIG. 3  is an exploded view of the present invention.  
       FIG. 4  is a sectional view of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      A brake drawing system of the present invention as illustrated in  FIGS. 2, 3 , and  4  is essentially comprised of a support bracket  10  fixed with a hydraulic cylinder  20  and pivoted with a brake pull rod  30 . Using the support bracket  10 , the entire brake drawing system is mounted to a handle  40  of a motorcycle, beach mobile or bicycle. Wherein, a pin lever  31  is axially disposed on the brake pull rod  30  to constitute transmission between the push rod  21  of the hydraulic cylinder  20  and the pull rod  30 , and the transmission is converted through the swing by the brake pull rod  30  into linear motion executed b the push rod  21 .  
      An adjustment bushing  32  is fastened to the pin lever  31  to allow penetration by the push rod  21 . Turning the adjustment bushing  32  changes relative positions between the adjustment bushing  32  and the pin lever  31 ; accordingly, openness of the brake pull or  30  is adjusted without interfering the push rod  21  to revolve on its axis so to ensure of maintaining the openness of the brake pull rod  30  as adjusted.  
      In practice, a gradation  211  to penetrate through the adjustment bushing  32  is disposed at the tail of the push rod  21 , and clamped by means of a locking ring  23  at where the push rod leaves the adjustment bushing  32  to constitute the coupling of the transmission between the push rod  21  and the adjustment bushing  32 . A locking ring (not illustrated) is each to the push rod  21  in relation to where externally to both ends of an adjustment bushing  32 . Furthermore, an adjustment nut is provided to the adjustment bushing  32  at where externally to the pin lever  31  for the user to directly turn the adjustment bushing  32  for immediate adjustment the openness of the brake pull rod  21 .  
      The prevent invention provides an improved structure of a brake drawing system applied in bikes and automobiles, and the application for a utility patent is duly filed accordingly. However, it is to be noted that the preferred embodiments disclosed in the specification and the accompanying drawings are not limiting the present invention; and that any construction, installation, or characteristics that is same or similar to that of the present invention should fall within the scope of the purposes and claims of the present invention.