Patent Publication Number: US-2012036967-A1

Title: Ratchet wrench having rotatably attached sockets

Description:
(a) TECHNICAL FIELD OF THE INVENTION 
     The present invention generally relates to ratchet wrenches, and especially relates to a ratchet wrench whose sockets could fit on nuts or bolts of various sizes. 
     (b) DESCRIPTION OF THE PRIOR ART 
     A ratchet wrench is a hand tool that includes a ratcheting mechanism that allows a bolt or nut to be tightened or loosened with a reciprocating motion, without requiring that the wrench be removed and refitted after each turn. A conventional ratchet wrench is shown in  FIGS. 1 and 2 . As illustrated, a head section  15  is formed in at least one of a wrench  10 &#39;s two ends. Inside the head section  15 , an engaging piece  16  and a selection rod  17  are provided where the selection rod  17  determines which direction the engaging piece  16  is turned by the wrench  10 . Separate, removable sockets  20  are provided to tighten or loose many different sizes of fittings and fasteners (e.g., nuts and bolts). Each socket  20  has a pivot hole  21  for joining with the engaging piece  16 , and a fitting hole  22  to fit a nut or bolt of a specific size. 
     For the conventional ratchet wrench described above, sockets  20  of various sizes have to be ready and changed when a different nut or bolt is encountered during usage. Not only a large number of sockets  20  have to be available and the repeated changes of sockets  20  cause operational inconvenience and delay. In addition, the pivot hole  21  and the fitting hole  22  of a conventional socket  20  is always axially aligned, which limits the design flexibility of the socket  20 . 
     In other words, the conventional ratchet wrench is limited by its structure and, therefore, a large number of sockets have to be ready and available and repeated socket changes are inevitable. This is especially troublesome when working at heights. In reality, the nuts and bolts of the same machine or apparatus usually have similar sizes. As such, if a socket could be designed to fit on nuts or bolts of different sizes, this would definitely enhance operational speed and convenience. 
     SUMMARY OF THE INVENTION 
     A major objective of the present invention is to provide a ratchet wrench having rotatably attached sockets that could fit on nuts or bolts of various sizes so as to enhance operational convenience. 
     To apply the ratchet wrench on bolts or nuts of different sizes, the attached sockets could be turned along an axis to select one matching the bolt or nut. As such, there is no need to carry a large number of removable sockets as in the prior arts and the sockets could be switched more quickly. In the mean time, as the ratchet wrench could be turned in a reciprocating motion to tighten or loosen the bolt or nut, without removing and refitting the ratchet wrench after each turn. The ratchet wrench of the present invention strikes a successful compromise between functionality and convenience. The ratchet wrench therefore enjoys a higher add-on value and economical benefit. 
     The foregoing objectives and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts. 
     Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective diagram showing a conventional ratchet wrench is joined with a socket. 
         FIG. 2  is a sectional diagram showing the conventional ratchet wrench and socket of  FIG. 1 . 
         FIG. 3  is a perspective diagram showing a ratchet wrench according to an embodiment of the present invention. 
         FIG. 4  is a perspective break-down diagram showing the various components of the ratchet wrench of  FIG. 3 . 
         FIG. 5  is a schematic side-view diagram showing the ratchet wrench of  FIG. 3 . 
         FIG. 6  is a schematic top-view diagram showing the ratchet wrench of  FIG. 3  is configured to operate in one direction. 
         FIG. 7  is a schematic top-view diagram showing the ratchet wrench of  FIG. 3  is configured to operate in another direction. 
         FIG. 8  is a schematic side-view diagram showing a ratchet wrench according an alternative embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following descriptions are exemplary embodiments only, and are not intended to limit the scope, applicability or configuration of the invention in any way. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the invention. Various changes to the described embodiments may be made in the function and arrangement of the elements described without departing from the scope of the invention as set forth in the appended claims. 
     As illustrated in  FIG. 3 , a ratchet wrench in accordance with an embodiment of the present invention contains a wrench  50 , and a head section  55  formed in at least one of the wrench  50 &#39;s two ends. In the present embodiment, each end of the wrench  50  is configured with a head section  55 . Inside the head section  55 , an engaging member  60  is provided. In the present embodiment, the two engaging members  60  are configured to the same side of the wrench  50  while, in an alternative embodiment shown in  FIG. 8 , the two engaging members  60  are configured to opposite sides of the wrench  50 . Each engaging member  60  has a pin-joined fitting element  65  with multiple fitting holes. For each head section  55 , a selection mechanism  70  is provided on a side opposite to the engaging member  60 . The selection mechanism determines which direction the engaging member  60  is turned by the wrench  50 . 
     As further shown in  FIGS. 4 and 5 , within each head section  55  of the wrench  50 , there are a through wheel chamber  56  and an open configuration chamber  58  laterally connected together. The wheel chamber  56  is to accommodate a gear wheel  61  of the engaging member  60 . The configuration chamber  58  is to accommodate the selection mechanism  70 . A cover piece  59  is used to seal an open side of the wheel chamber  56  and the configuration chamber  58 . 
     The gear wheel  61  is configured at an end of each engaging member  60 . Two opposing and parallel ear pieces  62  are extended from the other end of the engaging member  60  for pin-joining the fitting element  65 . On a first ear piece  62 , a bolt hole  620  is provided for a limiting element  63  to thread through. The limiting element  63 , from inside out, contains a steal ball, a spring, and a stopping bolt, so that the steal ball provides an elastic latching to the fitting element  65  through the bolt hole  620 . The fitting element  65  is positioned between the ear pieces  62  and is rotatably joined with the engaging member  60  by threading a pin  64  through the ear pieces  62  and a through axle hole  660  in a central axial section  66  of the fitting element  65 . The rotational axis of the fitting element  65  and the operational axis of the engaging member  60  are as such orthogonal. On the axial section  66 , a number of limiting indentations  661  are configured around the axle hole  660  for engaging the steal ball of limiting element  63 . A number of sockets are configured around the circumference of the fitting element  65 , and perpendicular to the rotational axis of the fitting element  65 . In the present embodiment, four sockets of different sizes, namely, a first socket  681 , a second socket  682 , a third socket  683 , a fourth socket  684 , are provided to fit on bolts or nuts of four different sizes. 
     The selection mechanism  70  contains two arm pieces  71  and  73  inside the configuration chamber  58 . The arm pieces  71  and  73  have a pivotal end and a free end. The pivotal ends are adjacent with each while the free ends are extended in a C-like shape towards two separate spots along the rim of the gear wheel  61  (as illustrated in  FIGS. 6 and 7 ). Teeth  710  and  730  are configured on inner sides of the free ends of arm pieces  71  and  73  interfacing with the gear wheel  61 , respectively. On the other hands, two elastic elements  72  and  74  are configured between the wall of the configuration chamber  58  and outer sides (opposite to the inner sides where teeth  710  and  730  are configured) of the arm pieces  71  and  73 &#39;s free ends, respectively. The two elastic elements  72  and  74  push the free ends (and therefore their teeth  710  and  730 ) to swing around the pivotal ends and to engage the gear wheel  61 . A selection block  75  is configured inside the configuration chamber  58  and between the arm pieces  71  and  73 . The selection block  75  is engaged by a selection switch  76  on the cover piece  59  which, in one of the selection switch  76 &#39;s two configurations, the arm pieces  71  or  73  are selectively pushed away from the gear wheel  61 . 
     As described above, a ratchet wretch compromising functionality (capable of operating various bolts or nuts) and convenience (no need to carry multiple sockets) are achieved. 
     The operation of the ratchet wretch is depicted in  FIGS. 3 ,  5 ,  6 , and  7 . As illustrated, to tighten or loose a bolt or nut, the selection switch  76  is set to a specific configuration where one of the arm pieces  71  and  73  is pushed away from the gear wheel  61  while the other arm piece  73  or  71  engages the gear wheel  61  by the corresponding elastic element  730  or  710 . As such, the wretch  50  (and therefore the engaging member  60 ) could be turned in a reciprocating motion to tighten or loosen a bolt or nut, without removing and refitting the ratchet wrench after each turn. 
     To apply the ratchet wretch on a bolt or nut, as shown in  FIGS. 3 and 5 , the fitting element  65  is rotated relatively to the engaging member  60  until one of the first, second, third, and fourth sockets  681 ,  682 ,  683 ,  684  that matches the bolt or nut faces is properly oriented downward. When the fitting element  65  is adjusted as described, the limiting element  63  locks into one of the limiting indentations  661  on the axial section  66  so that, during the ratchet wretch&#39;s operation, the fitting element  65  is confined and does not rotate arbitrarily. In the mean time, the first, second, third, and fourth sockets  681 ,  682 ,  683 ,  684  could be conveniently and quickly switched. 
     While certain novel features of this invention have been shown and described and are pointed out in the annexed claim, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention.