Patent Publication Number: US-6220125-B1

Title: Device for adjusting angle of ratchet wrench

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to a ratchet wrench, and more particularly to an angle adjusting device of the ratchet wrench. 
     BACKGROUND OF THE INVENTION 
     As shown in FIG. 1, the Taiwan Patent No. 82202299 discloses a ratchet wrench comprising a button  2  and a drive head  3 . The drive head  3  has a connection rod  4  which is received within an insertion hole  5 . The button  2  has a rack  1 , which is engaged with the insertion hole  5  in which a corresponding rack is provided. When the button  2  is pressed, the rack  1  of the button  2  is disengaged with the insertion hole  5  so as to enable the drive head  3  to be bent to form a predetermined angle with the handle  6 . As soon as the button  2  is relieved of the pressure exerting thereon, the button  2  is forced by the elastic force of a spring  7  to return to its original position. Such a prior art ratchet wrench as described above is defective in design in that the rack  1  of the button  2  is prone to displace and jam in the insertion hole  5 . In order to prevent the jamming of the rack  1 , it is necessary to turn the button  2  gently. The user of the prior art ratchet wrench is often annoyed by such inconvenience. 
     As shown in FIGS. 2 and 3, the Taiwan Patent Nos. 82210906 and 83206013 disclose respectively a ratchet wrench comprising a rod body  9  which is provided with a cam  8  for supporting an arresting member  10  so as to retain the drive head  11 . The rod body  9  is not provided with a means for causing the rod body  9  to return to its original position automatically. As a result, the user of such prior art ratchet wrenches must keep turning the rod body  9  at the same time as when the prior art ratchet wrenches are at work. In addition, the contact area of the drive head  11  and the arresting member  10  is smooth and is vulnerable to deformation. 
     Now referring to FIG. 4, the Taiwan Patent No. 8221506 discloses a ratchet wrench, which comprises a drive head  12  having two lugs  13  and a steel ball  14  located between the two lugs  13 . The steel ball  14  is intended to engage any one of the retaining slots  17  of the pivoting end  16  of the handle  15 . One of the two lugs  13  of the drive head  12  is provided with a hole  18  for receiving a spring pull member  19  which has a protruded rod  20 . The pivoting end  16  of the handle  15  is provided with a plurality of insertion holes  21 . The protruded rod  20  is inserted into one of the insertion holes  21 . In order to bend the drive head  12 , it is necessary to pull the spring pull member  19  so as to cause the protruded rod  20  to disengage the insertion hole  21  of the handle  15 . In the meantime, the steel ball  14  constantly supports any angle of any corresponding retaining slots  17  of the pivoting end  16  of the handle  15 . 
     It is therefore readily apparent that the prior art ratchet wrenches are complicated in construction and are therefore not cost-effective. In addition, the prior art ratchet wrenches can not be used with ease and convenience. 
     SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a ratchet wrench with an angle adjusting device which is free from the deficiencies of the prior art devices described above. 
     In keeping with the principle of the present invention, the foregoing objective of the present invention is attained by an angle adjusting device comprising a drive head, a handle, and a button. The drive head has a pivoting end at one end thereof. The handle has two pivoting lugs for fastening the pivoting end of the drive head at one end thereof. The handle also has a receiving slot for disposing the button in conjunction with a spring and a steel ball at one end thereof. The button has an OFF center slot for receiving the spring, a notch corresponding in location to a ball slot of the pivoting end of the drive head, and an inclined plane. The button is supported by the spring such that the steel ball is forced by the inclined plane of the button to reside in the ball slot of the pivoting end of the drive head. As the button is pressed, the steel ball falls back into the notch of the button to enable the drive head to be adjusted angularly. 
    
    
     The foregoing objective, features, functions, and advantages of the present invention will be more readily understood upon a thoughtful deliberation of the following detailed description of a preferred embodiment of the present invention with reference to the accompanying drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a schematic plan view of a ratchet wrench of the Taiwan Patent No. 82202299. 
     FIG. 2 shows a perspective view of a ratchet wrench of the Taiwan Patent No. 82210906. 
     FIG. 3 shows a schematic plan view of a ratchet wrench of the Taiwan Patent No. 83206013. 
     FIG. 4 shows an exploded view of a ratchet wrench of the Taiwan Patent No. 82215064. 
     FIG. 5 shows an exploded view of the preferred embodiment of the present invention. 
     FIG. 6 shows a perspective view of the preferred embodiment of the present invention. 
     FIG. 7 shows a sectional schematic view of the preferred embodiment of the present invention. 
     FIG. 8 shows a schematic view of the preferred embodiment of the present invention at work. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     As shown in FIGS. 5-8, the preferred embodiment of the present invention comprises a drive head  30 , a handle  40 , and a button  50 . 
     The drive head  30  is provided at one end thereof with a pivoting end  32  which is in turn provided with a plurality of ball-locating slots  34  and a through hole  36 . 
     The handle  40  is provided at a pivoting end  49  thereof with two pivoting lugs  43 , with each having a fisheye hole  41  and a threaded hole  42 . The pivoting end  32  of the drive head  30  is fastened pivotally between the two pivoting lugs  43  of the handle  40  by a sunk-head bolt  44  which is received in the through hole  36  of the pivoting end  32  of the drive head  30  and the threaded hole  42  of the two pivoting lugs  43  of the handle  40 . The pivoting end  49  of the handle  40  is further provided with a receiving slot  45  for receiving a spring  46  and the button  50 . The receiving slot  45  is provided in the midsection thereof with an open area  47  for receiving a steel ball  48 . 
     The button  50  is provided with a longitudinal OFF-center spring slot  52 , a notch  54 , and an inclined plane  56 . The OFF-center spring slot  52  is intended to receive the spring  46 . 
     In operation, the button  50  is mounted in the receiving slot  45  of the pivoting end  49  of the handle  40  such that the upper end of the button  50  extends outwardly of the upper end of the receiving slot  45  because the spring action of the spring  46 . The steel ball  48  is located at the notch  54  of the button  50  to prevent the button  50  from slipping out of the receiving slot  45 . As shown in FIG. 7, the button  50  is supported by the spring  46  such that the steel ball  48  slides down the inclined plane  56  of the button  50  to exit of the open slot  47  and to enter in the ball-locating slot  34 . Now referring to FIG. 8, as the button  50  is pressed, the steel ball  48  falls back into the notch  54  so as to enable the drive head  30  to form a new angle with the handle  40 . As soon as the button  50  is relieved of the pressure exerting thereon, the button  50  returns to its original position. 
     The embodiment of the present invention described above is to be regarded in all respects as being merely illustrative and not restrictive. Accordingly, the present invention may be embodied in other specific forms without deviating from the spirit thereof. The present invention is therefore to be limited only by the scope of the following appended claim.