Patent Publication Number: US-6698074-B1

Title: Pincers for assembling and disassembling the springs of the brake shoes in a drum brake

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a pair of pincers for assembling and disassembling the springs of the brake shoes in a drum brake, particularly to one able to be handled with ease and less labor. 
     2. Description of the Prior Art 
     Conventionally, a brake drum of a brake device of an automobile is installed on the axle for rotating together, having two brake shoes  1  disposed oppositely in the interior, as shown in FIG.  1 . The two brake shoes  1  are respectively provided with plural hook holes  10  for receiving two hook ends  20  of strong springs  2  so as to always urge inward the two brake shoes  1 , and each brake shoe  1  is fixed on the outer side with a brake lining  11  made of a coarse material and able to endure abrasion. When the brake of an automobile is actuated, two brake shoes  1  force two brake linings  11  to move outward and press the inner sides of the brake drum and accordingly produce a great frictional force to control the wheels of an automobile to stop. But, these brake linings  11  will gradually be worn off after the brake is employed for long, and under this condition, the brake shoes  1  have to be replaced with new ones so as to maintain the proper function of the brake and ensure safety of driving. 
     For the present, the strong springs  2  tightly hooking the brake shoes  1  are forcefully disassembled by means of a pair of needle nose pliers. However, when a pair of needle nose pliers clamps the hook end  20  of the spring  2  to carry out assembling and disassembling, it is not kept stable by any fulcrum, therefore a user has to pull it with a very huge force, thus not only increasing difficulty in assembling and disassembling and wasting labor and time but also possibly resulting in damage to the tools or to the components of an automobile. 
     SUMMARY OF THE INVENTION 
     This invention has been devised to offer a pair of pincers for assembling and disassembling the spring of the brake shoes in a drum brake, able to be operated with quickness and less force. 
     The feature of the invention is a position lever and a hook lever pivotally combined oppositely. The position lever has its upper end formed with a ball joint fitted around with a position member. The hook lever has its upper end formed with a hook facing the position member of the position lever. The position member further has a sleeve receiving the ball joint therein, able to turn around but impossible to disengage from the ball joint. Besides, the position member has it upper side formed with ratchet teeth, and the position lever and the hook lever respectively have a handle disposed at a lower portion, with one of the two handles provided with a lengthwise groove and a blocking member at the lower end. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     This invention will be better understood by referring to the accompanying drawings, wherein: 
     FIG. 1 is a cross-sectional view of a conventional drum brake device; 
     FIG. 2 is a perspective view of a pair of pincers in the present invention; 
     FIG. 3 is a perspective view of the pair of pincers in a condition of disassembling a spring from brake shoes in the present invention; and, 
     FIG. 4 is a perspective view of the pair of pincers in a condition of assembling the spring on the brake shoes in the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A preferred embodiment of a pair of pincers for assembling and disassembling the springs of the brake shoes in a drum brake of an automobile in the present invention, as shown in FIG. 2, includes a position lever  30  and a hook lever  31  respectively preset in its form as main components pivotally combined together. 
     The position lever  30  and the hook lever  31  are pivotally combined together by means of a rivet  4  and respectively have a handle  32  provided at the lower portion. The position lever  30  has its upper end formed with a ball joint  300  fitted around with a position member  33 , which has a sleeve  330  receiving the ball joint  300  therein, enabling the position member  33  to turn around. Besides, the position member  33  has its topside provided with umbrella-shaped ratchet teeth  331 . The hook lever  31  has its upper portion curved and formed on the upper end with a hook  310  facing the position member  33  of the position lever  30 . Further, one of the two handles  32  is provided with a lengthwise groove  320  having a blocking member  321  positioned at the lower end. 
     Thus, the position member  33  has its sleeve  330  fitting around the ball joint  300 , and the lower opening of the sleeve  330  is formed shrinking inward slightly so as to prevent the position member  33  from disengaging from the ball joint  300  and enable the position member  33  to be actuated to turn around by the ball joint  300 , and further the outer end of the ratchet teeth  311  of the position lever  33  faces the hook  310  of the hook lever  31 . 
     To disassemble the spring  2 , referring to FIGS. 3 and 4, simply hold and push outward two handles  32  of the position lever  30  and the hook lever  31  to let the upper portions of the two levers  30 ,  31  separate outward. Next, the ratchet teeth  331  of the position member  33  are forced by the ball joint  300  to firmly grab the outer wall of the brake shoes  1 , and the hook  310  of the hook lever  31  hooks the hook end  20  of the spring  2 . Lastly, hold close the two handles  32  to let the ratchet teeth  331  of the position lever  33  tightly grab the brake linings  11  to form a force-applying fulcrum and then have the hook  310  of the hook lever  31  removing the hook end  20  of the spring  2  out of the hook hole  10  of the brake shoes  1 , thus disassembling the spring  2  with quickness and with less force. 
     To assemble the spring  2 , referring to FIG. 4, firstly, one hook end  20  of the spring  2  is made to hook the brake shoes  1  and the other hook end  20  of the spring  2  is hooked by the groove  320  and the blocking member  321  at the lower end of the handle  32 . Next, pull forward the handle  32  together with the spring  2  to let the other hook end  20  of the spring  2  aligned with the hook hole  10  of the brake shoes  1  and then slightly pry the handle  32  to let the hook end  20  of the spring  2  move into the hook hole  10  of the brake shoes  1  along the groove  320  and the blocking member  321  of the handle  32 . 
     As can be noted from the above description, this invention has the following advantages. 
     1. It is able to be operated with ease and with less force and elevate work efficiency. 
     2. It is convenient to assemble and disassemble the spring of the brake shoes with quickness and security, impossible to cause any damage to the components of an automobile. 
     While the preferred embodiment of the invention has been described above, it will be recognized and understood that various modifications may be made therein and the appended claims are intended to cover all such modifications that may fall within the spirit and scope of the invention.