Patent Publication Number: US-7712397-B2

Title: Wrench assembly

Description:
CROSS REFERENCE 
   The present application is a continuation-in-part application of U.S. patent application Ser. No. 11/279,650, filed on Apr. 13, 2006, now abandoned, of which the entire disclosure is incorporated herein. 

   BACKGROUND OF INVENTION 
   1. Field of Invention 
   The present invention relates to a wrench assembly. 
   2. Related Prior Art 
   U.S. Pat. No. 5,996,448 discloses a socket wrench including a handle  2 , extension means  20  and a ratchet head  30 . The extension means  20  includes receiving means  22  for receiving a shank  8  of the handle  2  and a shank  24  for insertion in receiving means  32  of the ratchet head  30 . The shank  24  is equipped with a spring-loaded detent for abutting an internal face of the receiving means  32 . The shank  8  is equipped with a spring-loaded detent for abutting an internal face of the receiving means  22 . However, the detents cannot adequately retain the shank  24  within the receiving means  32  and the shank  8  within the receiving means  22 . As compensation, the shanks  24  and  8  must be high enough and the receiving means  32  and  22  must be thick enough. Such large dimensions however make it difficult to use the wrench within limited space. 
   U.S. Pat. No. 5,996,448 discloses a socket wrench including a handle  2 , extension means  20  and a ratchet head  30 . The extension means  20  includes receiving means  22  for receiving a shank  8  of the handle  2  and a shank  24  for insertion in receiving means  32  of the ratchet head  30 . The shank  24  is equipped with a spring-loaded detent for abutting an internal face of the receiving means  32 . The shank  8  is equipped with a spring-loaded detent for abutting an internal face of the receiving means  22 . However, the detents cannot adequately retain the shank  24  within the receiving means  32  and the shank  8  within the receiving means  22 . As compensation, the shanks  24  and  8  must be high enough and the receiving means  32  and  22  must be thick enough. Such large dimensions however make it difficult to use the wrench within limited space. 
   U.S. Pat. No. 7,000,504 discloses a ratchet wrench  10  including tool members  40  selectively and changeably received in a compartment  13  thereof. The tool member  40  includes a peripheral groove  43  in which a resilient ring member  43  is adapted to locate. The ring member  43  is made of rubber or other synthetic materials so that it can be squeezed. A ratchet wheel  21  is mounted between the compartment  13  and the tool member  40  and includes an inclined surface  27  on an upper portion thereof. In coupling the tool member  40  to the ratchet wrench  10 , the ring member  43  is inserted into a hole defined by the ratchet wheel  21  and is squeezed in order to pass through the hole. When the ring member  43  engages the inclined surface  27 , the ring member  43  returns to its original cross sectional profiles and the tool member  40  is attached to the ratchet wrench  10 . In disengaging the tool member  40  from the ratchet wrench, the process is reversed. While this attachment enables easy and quick engagement of the ratchet wrench  10  and the tool member  40 , it nevertheless suffers from some problems. Firstly, since the peripheral groove  43  provides no redundant recessed space into which the ring member  43  is adapted to move during the engagement/disengagement of the tool member  40  and the ratchet wrench  10 , the ring member  43  will rub against the ratchet wheel  21  and gradually wears out. Secondly, since the ring member  43  is made of rubber or other synthetic material and is not forced through the ratchet wheel  21  so as to be retained on the terminate edge of the ratchet wheel  21 , it has poor efficacy to reinforce connection of the tool member  40  and the ratchet wrench  10 . Thus the ring member  43  is easily accidentally disengaged with the inclined surface  27 . Thirdly, the ring member  43  is adapted to return to its original shape and engage with the inclined surface  27  when the tool member  40  engages with the ratchet wrench  10 . However, the tool member  40  gradually loses grip with the ratchet wrench  10  as the ring member  43  wears out. 
   The present invention is therefore intended to obviate or at least alleviate the problems encountered in the prior art. 
   SUMMARY OF INVENTION 
   According to the present invention, the wrench assembly includes a first wrench, a second wrench and a bar. The first wrench includes a first driving device at an end and a second driving device at an opposite end. The second wrench includes a first driving device at an end and a second driving device at an opposite end. The bar includes a first connecting device for connection to the second driving device of the first wrench and a second connecting device for connection to the first driving device of the second wrench. The first connecting device includes a first annular groove spaced from the bar greater than a thickness of the second driving device of the first wrench. The second connecting device includes a second annular groove spaced from the bar greater than a thickness of the first driving device of the second wrench. 
   A first C-clip is compressible and has a first extent parallel to and at least equal to a depth of the first annular groove when the first C-clip is received in the first annular groove. Further, the first C-clip has an outer diameter located outwardly of the first annular groove and an inner diameter located within the first annular groove when the first C-clip is in an expanded condition. The first C-clip is adapted to reinforce the connection of the first connecting device of the bar to the second driving device of the first wrench. 
   A second C-clip is compressible and has a second extent parallel to and at least equal to a depth of the second annular groove when the second C-clip is received in the second annular groove. Further, the second C-clip has an outer diameter located outwardly of the second annular groove and an inner diameter located within the second annular groove when the second C-clip is in an expanded condition. The second C-clip is adapted to reinforce the connection of the second connecting device of the bar to the first driving device of the second wrench. 
   Preferably, the first and the second C-clips are made of metal and have a circular cross-sectional profile. 
   An advantage of the wrench assembly of the present invention is that the C-clips ensure adequate connection of the first and second wrenches to the bar. 
   An advantage of the wrench assembly of the present invention is that the first and second wrenches and the bar are thin and easily operable within limited space, since the interconnection is ensured. 
   Other advantages and features of the present invention will become apparent from the following description referring to the drawings. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
     The present invention will be described through detailed illustration of four embodiments referring to the drawings. 
       FIG. 1  is a perspective view of a wrench assembly according to the first embodiment of the present invention. 
       FIG. 2  is an exploded view of the wrench assembly of  FIG. 1 . 
       FIG. 3  is a side view of the wrench assembly of  FIG. 1 . 
       FIG. 4  is an enlarged partial side view, partially in section of the wrench assembly shown in  FIG. 3 . 
       FIG. 4A  is a top view of a C-clip shown in  FIG. 4 . 
       FIG. 5  is another enlarged partial side view, partially in section of the wrench assembly shown in  FIG. 3 . 
       FIG. 5A  is a top view of the C-clip shown in  FIG. 5 , with the shape of the C-clip in  FIG. 4A  shown in phantom. 
       FIG. 6  is an exploded view of a wrench assembly according to a second embodiment of the present invention. 
       FIG. 7  is a side view of the wrench assembly of  FIG. 6 . 
       FIG. 8  is an exploded view of a wrench assembly according to a third embodiment of the present invention. 
       FIG. 9  is a side view of the wrench assembly of  FIG. 8 . 
       FIG. 10  is an exploded view of a wrench assembly according to a fourth embodiment of the present invention. 
       FIG. 11  is a side view of the wrench assembly of  FIG. 10 . 
   

   DETAILED DESCRIPTION OF EMBODIMENTS 
   Referring to  FIGS. 1-3 , a wrench assembly is shown according to a first embodiment of the present invention. The assembly includes a first wrench  10 , a second wrench  20  and a bar  30 . 
   The first wrench  10  includes a first driving device  13  at a first end  11  and a second driving device  14  at a second end  12 . The first driving device  13  is preferably a selective one-way driving device. The second driving device  14  is preferably a box end. The first wrench  10  further includes an upper surface  15  and a lower surface  16  spaced from the upper surface  15 . The second driving device  14  has a thickness substantially equal to the spacing between the upper and lower surfaces  15  and  16 . 
   The second wrench  20  includes a first driving device  23  formed at a first end  21  and a second driving device  24  formed at a second end  22 . The first driving device  23  is preferably a box end. The second driving device  24  is preferably an open end. The second wrench  20  further includes an upper surface  26  and a lower surface  25  spaced from the upper surface  26 . The first driving device  23  has a thickness substantially equal to the spacing between the upper and lower surfaces  26  and  25 . 
   The bar  30  includes a first end  31 , a second end  32  and a middle section  33  between the ends  31  and  32 . An upper surface  34  of the middle section  33  and lower surfaces  35  of the ends  31  and  32  are substantially in the same plane. The bar  30  further includes a first connecting device  36  on the lower surface  35  of the first end  31  and a second connecting device  37  on the lower surface  35  of the second end  32 . The first connecting device  36  is preferably a toothed stud defining a first annular groove  361  for receiving a first C-clip  362 . The second connecting device  37  is preferably a toothed stud defining a second annular groove  371  for receiving a second C-clip  372 . The C-clips  362  and  372  are preferably made of metal and include a circular cross-sectional profile. 
   As shown in the figures, the first and second annular grooves  361  and  371  define a first space  363  and a second space  373 , respectively. The first space  363  and the second space  373  have a first depth and a second depth, respectively. Also, the first annular groove  361  is spaced from the lower surface  35  of the first end  31  greater than the thickness of the second driving device  14  of the first wrench  10  and the second annular groove  371  is spaced from the lower surface  35  of the second end  31  greater than the thickness of the second driving device  14  of the first wrench  10 . 
   Referring to  FIGS. 4 through 5 , the first C-clip  362  is compressible and has a first extent parallel to and at least equal to the first depth when the first C-clip  362  is received in the first annular groove  361 . The first C-clip  362  has an outer diameter located outwardly of the first annular groove  361  and an inner diameter located within the first annular groove  361  when the first C-clip  362  is in an expanded condition. Please note, although not illustrated, but it is understood that the second C-clip  372  has a second extent parallel to and at least equal to the second depth when the second C-clip  372  is received in the second annular groove  371 . The second C-clip  372  has an outer diameter located outwardly of the second annular groove  371  and an inner diameter located within the second annular groove  371  when the second C-clip  372  is in an expanded condition. 
   To connect the first wrench  10  to the bar  30 , the first C-clip  362  is first disposed in the first annular groove  361 . Then, the first C-clip  362  is forced into the first space  363  of the first annular groove  361  of the first connecting device  36  such that the C-clip  362  is completely received by the first annular groove  361  and thereby prevents abrasion between the first C-clip  362  and the second driving device  14  of the first wrench  10 . After the first C-clip  362  passes through the second driving device  14  of the first wrench  10 , the first C-clip  362  is in an expanded condition to securely reinforce connection of the first connecting device  36  of the bar  30  to the second driving device  14  of the first wrench  10 . Likewise, as for securely connecting the second wrench  20  to the bar  30 , the second C-clip  372  is first disposed in the second annular groove  371 . Then, the second C-clip  372  is forced into the second space  373  of the second annular groove  371  of the second connecting device  37  such that the second C-clip  372  is completely received by the second annular groove  371  and thereby prevents abrasion between the second C-clip  372  and the first driving device  23  of the second wrench  20 . When the second C-clip  372  passes through the first driving device  23  of the second wrench  20 , the second C-clip  372  is in an expanded condition to securely reinforce connection of the second connecting device  37  of the bar  30  to the first driving device  23  of the second wrench  20 . In disengaging the first wrench  10  and/or the second wrench  20  from the bar  30 , the processes are reversed. 
   In this embodiment, the cross-sectional profile of the first C-clip  362  and the second C-clip  372  can remain circular and undeformed when being forced through the second driving device  14  of the first wrench  10  and first driving device  23  of the second wrench  20 , respectively. Also, when the first wrench  10  and the second wrench  20  are locked to the bar  30 , the first and second C-clips  362  and  372  are resiliently biased to their original shape. 
     FIGS. 6 and 7  show a wrench assembly according to a second embodiment of the present invention. The second embodiment is like the first embodiment, except that the first wrench  10  includes a second driving device  14   a , which is preferably a toothed stud defining an annular groove  141   a  for receiving a C-clip  142   a . The second wrench  20  includes a first driving device  23   a , which is preferably a toothed stud defining an annular groove  231   a  for receiving a C-clip  232   a . Further, the bar  30  includes two connecting devices  36   a  and  37   a , which are preferably box ends. 
     FIGS. 8 and 9  show a wrench assembly according to a third embodiment of the present invention. The third embodiment is like the first embodiment, except that the first wrench  10  includes a second driving device  14   a , which is preferably a toothed stud defining an annular groove  141   a  for receiving a C-clip  142   a . The bar  30  includes a first connecting devices  36   a , which is preferably a box end. 
     FIGS. 10 and 11  show a wrench assembly according to a fourth embodiment of the present invention. The fourth embodiment is like the first embodiment, except that the second connecting device  37  is on the upper surface  34  of the second end  32 . 
   Therefore, in accordance with the aforementioned, the wrench assembly of the present invention exhibits several advantages. Firstly, the C-clips  362 ,  372 ,  142   a , and  232   a  in the annular grooves  361 ,  371 ,  141   a , and  231   a  ensure adequate connection of the first and second wrenches  10 ,  20  to the bar  30 . Secondly, the wrench assembly is easily operable within a limited space. Thirdly, the C-clips  362 ,  372  are made of metal, and the annular grooves  361 ,  371   142   a , and  232   a  are adapted to completely receive the C-clips  362 ,  372   142   a , and  232   a , and thereby ensure that the C-clips  362 ,  372   142   a , and  232   a  have a long, useful life. 
   The present invention has been described via the illustration of the embodiments. Those skilled in the art can derive variations from the embodiments without departing from the scope of the present invention. Therefore, the embodiments shall not limit the scope of the present invention defined in the claims.