Patent Publication Number: US-2005135876-A1

Title: Connection of tool handle with tool bit

Description:
This Application is a Continuation-in-Part of my application Ser. No. 10/352,647 filed on Feb. 27, 2003. 
    
    
     BACKGROUND OF INVENTION  
      1. Field of Invention  
      The present invention relates to a tool including a handle and a tool bit for releasable engagement with the handle and, more particularly, to a connector for connecting the handle with the tool bit.  
      2. Related Prior Art  
      U.S. Pat. No. 5,531,140 discloses a conventional connector including a rod  10 , a ball detent  15 , a control bar  20 , a spring  24  and a button  30 . The rod  10  defines an axial cavity  13 . The control bar  20  includes a slot  21  longitudinally extending therein. The slot  21  including a long opening in a first side and a short opening in a second side opposite to the first side. In addition, a deep recess  22  and a shallow recess  22  are defined in the second side of the rod  20 . The button  30  includes a hook  31  formed at an end and an inclined edge  32  formed next to the hook  31 . The ball detent  15  is put in the hole  14 . The wall of the hole  14  is processed so as to trap the ball detent  15  in the hole  14 . The wall of the hole  14  is processed so as to trap the ball detent  15  in the hole  14 . The spring  24  is received in the axial cavity  13 . The control bar  20  is inserted into the axial cavity  13 . The control bar  20  is biased by means of the spring  24 . The button  30  is partially inserted into the hole  11 . The hook  31  is received in the long opening of the slot  21  and the inclined edge  32  is received in the short opening of the slot  21 . Normally, the ball detent  15  is partially received in the shallow recess  23  and partially inserted from the hole  14  for locking a tool bit. The button  30  can be pushed in order to move the control bar  20  further into the axial cavity  13 . Thus, the ball detent  15  is partially received in the deep recess  22  and hidden in the hole  14 .  
      U.S. Pat. No. 4,938,107 discloses a wedge locking socket device with an extension shank  9  and a socket  21 . The extension shank  9  includes a driving portion  12 . The socket  21  defines a recess for receiving the driving portion  12 . The driving portion  12  includes a shoulder  58  formed thereon, a slot  10  defined therein and a hole  19  communicated with the slot  10 . A limiting collar  52  is mounted on the driving portion  12  with an end located against the shoulder  58 . A spring  17  is mounted on the driving portion  12 . A sleeve  15  is mounted on the driving portion  12 . The sleeve  15  includes two rings  28  and  29  formed on an internal side. The spring  17  is compressed between the limiting collar  52  and the ring  28 . Two ball detents  22  and  24  are put in the hole  19 . A control bar  14  is put in the slot  10 . The control bar  14  includes a spur  16  and an inclined edge  22 . The spur  16  is held between the rings  28  and  29 . The spring  17  pushes the sleeve  15  and therefore the control bar  14  towards the ball detents  22 . Because of engagement of the inclined edges  25  with the ball detent  22 , the control bar  14  and the ball detent  24  are moved outwardly so as to abut against two opposite walls  31  of the recess defined in the socket  21 . The sleeve  15  and therefore the control bar  14  can be moved from the ball detent  22  in order to disengage the control bar  14  and the ball detent  24  from the walls  31 .  
     SUMMARY OF THE INVENTION  
      It is the primary objective of the present invention to provide a structurally simple connector for connecting a tool with a tool bit.  
      According to the present invention, a connector for connecting a tool handle with a tool bit includes a shank, a spring, a detent and a switch. The shank includes a first end, a second end, a non-circular insert formed at the second end for insertion in a corresponding hole defined in the tool bit, a terminal hole extending therein obliquely with respect thereto and a peripheral hole communicated with the terminal hole. The spring is inserted in the terminal hole. The detent is movably inserted in the terminal hole and includes a first end biased by means of the spring and a second and extensible from the terminal hole for engagement with the wall of the hole defined in the tool bit. The switch is connected with the detent through the peripheral hole.  
      Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the attached drawings.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The present invention will be described through detailed illustration of embodiments referring to the attached drawings.  
       FIG. 1  is a perspective view of a connector according to a first embodiment of the present invention.  
       FIG. 2  is an exploded view of the connector shown in  FIG. 1 .  
       FIGS. 3-7  are cross-sectional views of the connector shown in  FIG. 1 .  
       FIG. 8  is a perspective view of a connector view of a connector according to a second embodiment of the present invention.  
       FIG. 9  is a perspective view of a connector according to a third embodiment of the present invention.  
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS  
      Referring to  FIGS. 1-3 , according to a first embodiment of the present invention, a connector  1  for connecting a tool handle (not shown) with a tool bit or socket  6  ( FIGS. 4-7 ) is shown. The connector  1  includes an extension shank  2 , a detent  3  and a switch  4 .  
      The extension shank  2  includes a first end and a second end. A socket  24  is formed at the first end of the extension shank  2 . The socket  24  defines a non-circular hole for receiving a corresponding end of the tool handle. Thus, pivoting of the handle causes pivoting of the extension shank  2 . A non-circular insert  21  is formed at the second end of the extension shank  2  for insertion in a corresponding hole  61  defined in the tool bit or socket  6 . Thus, rotation of the extension shank  2  causes rotation of the socket  6  or tool bit. The detent  3  and the switch  4  are installed at the second end of the extension shank  2  in order to control the engagement of the insert  21  with the socket  6 .  
      The extension shank  2  defines a terminal hole  22 . The length of the terminal hole  22  is not parallel to that of the extension shank  2 . The extension shank  2  defines a peripheral hole or slot  23  communicated with the terminal hole  22 .  
      The terminal hole forms a preferred angle relative to the shank  2  which is generally less than six (6) degrees.  
      A spring  33  is inserted in the terminal hole  22 . The detent  3  is in the form of a rod. The detent  3  is movable inserted in the terminal hole  22 . The detent  3  includes a first end and a second end. The first end of the detent  3  is biased by means of the spring  33  so that the second end of the detent  3  tends to extend out of the terminal hole  22 . A rough area  31  is formed on the detent  3  at or near the second end for firm engagement with the wall of the hole  61 . The rough area  31  is a plurality of ribs. A hole  32  is defined in the detent  3  near the first end.  
      More preferably, the angle formed on the terminal hole relative to the shank  2  is arranged between three (3) degrees and six (6) degrees. Under the specific range of the angle, the detent  3  can provide friction between the detent  3  and the inner wall of the socket  6 . Instead of ribs, the area  31  is preferably formed with an edge having a slightly convex smooth curve. The contact area between the detent  3  and the socket inner wall is much larger owing to the angle therebetween being relatively small. The larger contact area obtains a stronger friction force of engagement between the insert  21  and the socket  6 , and reaches a phenomenon tending to efficiently expand the inner wall of the socket, thereby being liable to prevent the socket  6  from being disengaged due to the undesired external force. In addition, due to the small oblique angle of the detent  3  as disposed, the detent  3  is not liable to be retracted in the hole  22  owing to the force applied from the inner wall of the socket  6 . This design causes the shank  2  to be firmly in engagement with the socket  6  when in use.  
      The switch  4  is in the form of a sleeve movably mounted on the second end of the extension shank  2 . The switch  4  defines an axial hole  41  through which the second end of the extension shank  2  is inserted and a radial hole  43  communicated with the axial hole  41 . A pin  5  is inserted through the holes  43  and  23  into the hole  32 , thus combining the detent  3  with the switch  4 . A ring  45  is mounted on the switch  4  so as to keep the pin  5  in position. An annular groove  42  is defined in the periphery of the switch  4  for receiving the ring  45 . Several annular ribs  44  are formed on the periphery of the switch  4  for contact with a hand of a user (not shown). To facilitate user&#39;s operation, the switch  4  is preferably configured to be a slightly tapered shape having a larger diameter at the end of shank  2  and a smaller diameter at the end of the socket  6 .  
      Referring to  FIG. 4 , the user moves the second end of the detent  3  into the terminal hole  22  by way of pushing the switch  4 . Then, the user inserts the insert  21  into the hole  61 .  
      Referring to  FIG. 5 , the user releases the detent  3  via releasing the switch  4 . As the detent  3  is biased by means of the spring  33 , the second end of the detent  3  extends from the terminal hole  22  so as to abut against the wall of the hole  61 .  
      Referring to  FIG. 6 , if the user unintentionally pulls the socket  6  away from the extension shank  2 , the user brings the second end of the detent  3  further from the terminal hole  22 , thus enhancing the engagement of the second end of the detent  3  with the wall of the hole  61 . Therefore, unintentional disengagement of the socket  6  from the extension shank  2  is avoided.  
      Referring to  FIGS. 4-6 , in the wall of the hole  61  is defined an annular groove  62  for receiving a ball detent of a typical connector (not shown). Referring to  FIG. 7 , the connector is used for connection with a socket  6 ′ different from the sock  6  in that it does not include the annular groove  62 . It is obvious that the connector of the present invention can be used for connection with a socket with or without an annular groove such as the annular groove  62 .  
       FIG. 8  shows a connector according to a second embodiment of the present invention. The second embodiment differs from the first embodiment in that the first end of the extension shank  2  is connected with a handle  7  instead of formed with the socket  24 .  
       FIG. 9  is a perspective view of a connector according to a third embodiment of the present invention. The third embodiment differs from the first embodiment in that the first end of the extension shank  2  is formed with a universal joint  8  instead of the socket  24 .  
      The present invention has been described via illustration of some embodiments. The applicant gives these embodiments only as examples, and those skilled in the art can derive variations from the embodiments after a study of this specification. Therefore, these embodiments shall not limit the scope of the present invention that is defined in the following claims.