Patent Publication Number: US-2011072940-A1

Title: Wrench having detachable wrench head

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to a wrench, and more specifically to a wrench having at least one detachable wrench head for driving a nut or bolt head. 
     2. Description of the Related Art 
       FIG. 1  shows a conventional wrench  10  comprising a handle  12  and two wrench heads  14 . The handle  12  has a socket  122  through two ends thereof for insertion of the wrench heads  14 , and two pairs of protrusions  124 . As shown in  FIG. 2 , each pair of the protrusions  124  are respectively projected out from the inner periphery walls of the top and bottom sides of the handle  12  for engagement with holes  142  of the wrench heads  14 , thereby enabling the wrench heads  14  to be mounted with the handle  12 . According to this design, the wrench heads  14  are undetachable from the handle  12  after they are mounted with the handle  12  by means of the engagement between the protrusions  124  of the handle  12  and the holes  142  of the wrench heads  14 . Under this circumstance, the wrench  10  will become functionless and discardable if one of the wrench heads  14  is damaged, resulting in waste of the product. 
     SUMMARY OF THE INVENTION 
     It is one objective of the present invention to provide a wrench having a detachable wrench head for facilitating maintenance and replacement of the damaged wrench head. 
     To achieve this objective of the present invention, the wrench comprises a handle having an end surface defining a socket and an outer periphery defining a hole in communication with the socket, a wrench head having a head portion and a body portion integrally extending from the head portion and inserted in the socket of the handle and provided with a recess aligned with the hole of the handle, and a fastener detachably fastened to the hole of the handle and having a distal end inserted in the recess of the wrench head. 
     By means of removing the fastener from the hole of the handle, the damaged wrench head can be detached from the socket of the handle for maintenance or replacement, promoting a decrease in waste of the product. 
     Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein: 
         FIG. 1  is an exploded view of a wrench according to a prior art; 
         FIG. 2  is a partial cutaway view of the wrench according to the prior art; 
         FIG. 3  is a perspective view of a wrench according to a first preferred embodiment of the present invention; 
         FIG. 4  is an exploded view of the wrench according to the first preferred embodiment of the present invention; 
         FIG. 5  is a partial cutaway view of the wrench according to the first preferred embodiment of the present invention; and 
         FIG. 6  is a perspective view of the wrench according to a second preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in  FIGS. 3 and 4 , a wrench  20  in accordance with a first preferred embodiment of the present invention comprises a handle  30 , a first wrench head  40 , a second wrench head  50 , and two fasteners  60 . 
     The handle  30  is solid, having two end surfaces each defining a socket  32 , and an outer periphery defining two holes  34 , each of which communicates with one of the sockets  32 . A line defined between the holes  34  of the handle  30  isn&#39;t parallel to an axial direction of the handle  30 . 
     The first wrench head  40  includes a first head portion  42  having a U-shaped opening  422  for engagement with a nut or bolt head, and a first body portion  44  integrally extending from the first head portion  42  and inserted into one of the sockets  32  of the handle  30  and having a first recess  442  at a distal end thereof aligned with one of the holes  34  of the handle  30 . 
     The second wrench head  50  includes a second head portion  52  having a circular mounting hole  522  for installation of a ratchet wheel  56 , and a second body portion  54  integrally extending from the second head portion  52  and inserted into the other of the sockets  32  of the handle  30  and having a second recess  542  at a distal end thereof aligned with the other of the holes  34  of the handle  30 . 
     As shown in  FIG. 5 , each of the fasteners  60  is embodied as a screw so as to be screwed to one of the holes  34  of the handle  30 , and provided with a distal end inserted into one of the first recess  442  of the first wrench head  40  and the second recess  542  of the second wrench head  50  for fastening the first and second wrench heads  40  and  50  to the handle  30 . 
     When the wrench  20  has been used for a long time, the first head portion  42  of the first wrench head  40  or the second head portion  52  of the second wrench head  50  may suffer a damage severe enough to result in that the nut or bolt head can&#39;t be grasped tightly by the first head portion  42  of the first wrench head  40  or the ratchet wheel  56  can&#39;t be assembled securely with the second head portion  52  of the second wrench head  50 . Under this situation, a user can use a screwdriver to remove the fastener  60  associated with the damaged wrench head in order to draw out the damaged wrench head from the socket  32  of the handle  30  for maintenance or replacement. Thereafter, the user can insert a repaired or new wrench head into the socket  32  of the handle  30  and then tighten the fastener  60  again to complete the replacement work, thereby attaining the purpose of reducing the waste of the product. 
     The wrench of the present invention can be made with various kinds of design on the basis of the spirit of the present invention. As shown in  FIG. 6 , a wrench  70  in accordance with a second preferred embodiment of the present invention is substantially similar to the aforesaid first embodiment with the exception of the positions of the holes  722  of the handle  72 . The line defined between the holes  722  of the handle  72  is parallel to the axial direction of the handle  72  such that the first and second wrench heads  74  and  76  are located on the same imaginary plane after fastened to the handle  72 . 
     The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.