Patent Publication Number: US-2004045416-A1

Title: Hand tool

Description:
CROSS-REFERENCE  
     [0001] The present application is a continuation-in-part application of U.S. patent application Ser. No. 09/941991. 
    
    
     
       BACKGROUND OF INVENTION  
       [0002] 1. Field of Invention  
       [0003] The present invention is related to a hand tool and more particularly to a hand tool including a handle and a bit engaged with the handle.  
       [0004] 2. Related Prior Art  
       [0005] U.S. Pat. No. 5,934,384 discloses a conventional drill that includes a transmission shaft  1 , a stop member  2 , a C-clip  3 , a compression spring  4 , a locating ring  5 , a chuck  6  and a bit  8 . The transmission shaft  1  includes a coupling hole  10  defined in an end for receiving the bit  8  and a coupling rod  13  extending from an opposite end for engagement with a motor. In the periphery of the transmission shaft  1  is defined a locating groove  11 . The transmission shaft  1  defines a through hole  110  through which the coupling hole  10  is communicated with the locating groove  11 . The stop member  2  includes an arched body and a rod  20  extending from a midpoint of the arched body. The arched body of the stop member  2  is put in the locating groove  11  while the rod  20  is inserted in the through hole  110 . In the periphery of the transmission shaft  1  is defined an annular groove  12  for receiving the C-clip  3 . The compression spring  4  is mounted on the transmission shaft  1 . The chuck  6  defines a central through hole  60  that includes a tapered orifice  61 . The chuck  6  is mounted on the transmission shaft  1  so as to enclose the stop member  2 , the C-clip  3  and the compression spring  4 . The locating ring  5  is fit in the chuck  6 . The compression spring  4  is compressed between the C-clip  3  and the locating ring  5 . The tapered orifice  61  pushes the arched body of the stop member  2  so as to insert the rod  20  into the coupling hole  10 . The bit  8  includes a shank  80  including several angles  81  in each of which a cut  82  is defined for receiving the rod  20 . The chuck  6  is pulled from the transmission shaft  1  so as to move the tapered orifice  61  from the arched body of the stop member  2 . Thus, the rod  20  leaves the coupling hole  10 . Hence, the shank  80  of the bit  8  can be inserted into or pulled from the coupling hole  10 . However, such pulling requires delicate actions of a hand, i.e., holding the transmission shaft  1  with the palm and four fingers and pushing the chuck  6  with the thumb. Moreover, a distance taken from the bit  8  to the coupling rod  13  is not adjustable for only one cut  82  is defined in each of the angles  81  of the periphery  80  of the bit  8 .  
       [0006] There have been devised various hand tools that each include a bit engaged with a handle in a releasable manner. Generally, such a bit includes an insert, and such a handle includes a socket for receiving the insert. A locking device is used to lock the insert in the socket.  
       [0007] The present invention is hence intended to obviate or at least alleviate the problems encountered in prior art.  
       SUMMARY OF INVENTION  
       [0008] It is an objective of the present invention to provide a tool including a handle and a bit that can easily be engaged with and disengaged from the handle.  
       [0009] It is another objective of the present invention to provide a tool including a handle and a bit that can be engaged with the handle in various positions.  
       [0010] According to the present invention, a tool includes a handle, a bit and a locking device. The handle includes a socket defining a first tunnel, a second tunnel and at least one aperture through which the first tunnel is communicated with the second tunnel. The bit includes a working head formed at an end, a shank formed at an opposite end and a series of recesses defined in the shank. The shank can be inserted in the first tunnel. The locking device includes at least one ball detent and a latch. The at least one ball detent is put in the aperture. The latch extends in the second tunnel for pushing the ball detent into one of the recesses in a locking position and defining at least one notch for receiving the ball detent in a releasing position.  
       [0011] 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 DRAWINGS  
     [0012] The present invention will be described through detailed illustration of two embodiments referring to the attached drawings wherein:  
     [0013]FIG. 1 is a perspective view of a tool including a handle and a bit engaged with the handle according to a first embodiment of the present invention.  
     [0014]FIG. 2 is an exploded view of the tool of FIG. 1.  
     [0015]FIG. 3 is a cross-sectional view of the tool of FIG. 1.  
     [0016]FIG. 4 is similar to FIG. 3, but showing the handle in a releasing position for the bit.  
     [0017]FIG. 5 is similar to FIG. 4, but showing the handle in a locking position for the bit.  
     [0018]FIG. 6 is a cross-sectional view of a tool including a handle and a bit engaged with the handle according to a second embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS  
     [0019] Referring to FIG. 1, according to a first embodiment of the present invention, a tool includes a handle  10 , a bit  30  and a locking device  20  for locking the bit  30  to the handle  10 . The bit  30  may be a crow.  
     [0020] Referring to FIG. 2, the bit  30  includes a prying head  32  and a shank  34  for engagement with the handle  10 . The shank  34  includes a series of recesses  31  defined therein.  
     [0021] The handle  10  includes a socket  12  formed at an end. The socket  12  defines a first tunnel  11 , a second tunnel  13  extending in parallel with the first tunnel  11  and two apertures  14  through which the first tunnel  11  is communicated with the second tunnel  13 . As known in the art, the first tunnel  11  is shaped corresponding to the shank  34  so as to receive the shank  34  non-rotationally. Each of the apertures  14  includes a first end at the first tunnel  11  and a second end at the second tunnel  13 . The first end is smaller than the second end.  
     [0022] The locking device  20  includes two ball detents  21 , a latch  23  and a spring  22 . The latch  23  includes an end inserted in the second tunnel  13  and an opposite end formed with a button  26 . Two notches  24  are defined in the latch  23 . Each of the notches  24  includes a slope  25 .  
     [0023] In assembly, the latch  23  is inserted through the spring  22  into the second tunnel  13  so that the apertures  14  are aligned with the notches  24 . Each of the ball detents  28  is forced into one of the apertures  14  through the first end. Thus, each of the ball detents  21  is trapped in one of the apertures  14  and one of the notches  24 .  
     [0024] As inserted into the first tunnel  11 , the shank  34  pushes the ball detents  21  completely from the first channel  11 . In turn, the ball detents  21  push of the slopes  25 , thus causing the latch  23  to move.  
     [0025] Referring to FIG. 3, the shank  34  is inserted in the socket  12 . Two of the recesses  31  are aligned with the apertures  14  so as to receive the ball detents  21  pushed by means of the slopes  25 . The latch  23  is kept in this position by means of the spring  22  compressed between the socket  12  and the button  26 .  
     [0026] Referring to FIG. 4, the button  26  is pressed so that the slopes  25  are moved from the ball detents  21 . Thus, the ball detents  21  can move further into the notches  24 . That is, the ball detents  21  can completely escape the notches  31 . Therefore, the shank  34  can be inserted further into the first tunnel  11 . Although not shown, the shank  34  can be pulled from the first tunnel  11  as the button  26  is pressed.  
     [0027] Referring to FIG. 5, the button  26  is released again. The bit  30  is locked to the handle  10  in a different position than the position shown in FIG. 3.  
     [0028] The tool may include an additional bit  36 . The additional bit  36  may be a screwdriver. The additional bit  36  includes a screw-driving head  38  and a shank  40 . In this case, the handle  10  includes a socket  15  formed at an opposite end for receiving the shank  40 .  
     [0029]FIG. 6 shows a tool according to a second embodiment of the present invention. The second embodiment is identical to the first embodiment except for three points. Firstly, a chisel  30  is used instead of the bit  30 . Secondly, the first tunnel  11  and the second tunnel  13  extend perpendicular to the handle  10 . Thirdly, a grip  18  is formed on the handle  10 .  
     [0030] Two embodiments of the present invention have been described in detail for illustration of the present invention. Those skilled in the art can derive variations from these embodiments. Hence, these embodiments shall not limit the scope of the present invention that can only be defined in the claims.