Abstract:
A screwdriver includes a hollow handle in which a bit set is slidably received and the bit set receives bits. A shank extends from a front end of the handle. A first end of the bit set is connected to a head member and a second end of the bit set is connected to a cap which is rotatably and disengagably connected to a rear end of the handle. A limit ring extends radially inward from the inside of the handle so that when the bit set is pulled from the handle to a position where the head member is stopped by the limit ring.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a screwdriver which has a shank extending from a front end of a handle of the screwdriver and a bit set for receiving bits is slidably received in the handle. 
     BACKGROUND OF THE INVENTION 
     A conventional screwdriver generally includes a handle and a shank extending from a front end of the handle. The shank has an engaging hole defined in a distal end of the shank so that different bits can be engaged with the engaging hole of the shank and perform different functions. The screwdriver is convenient for the user to carry and bits can be easily replaced and engaged with the shank. However, the bits are received in a box and the box is independent from the screwdriver so that the user has to carry the bit box and the screwdriver. A cartridge type screwdriver is developed and disclosed in U.S. Pat. No. 5,265,504 to Fruhm, with the title of “Cartridge Type Screwdriver”. The shank of the cartridge type screwdriver includes a neck portion which is securely engaged with a passage of the handle. The engagement between the neck portion and the passage requires a large mold set to manufacture and complicated checking processes to position the neck portion in the passage so that the screwdriver is incurred by high manufacturing cost. The shank is made of metal and has the same length as the handle so that each screwdriver employs a certain amount of metal which makes the price of the screwdriver be high. Besides, the magazine has no proper support when it is pulled out from the handle. 
     The present invention intends to provide a screwdriver having a bit set slidably received in the handle and the bit set is well positioned when it is pulled from the handle. 
     SUMMARY OF THE INVENTION 
     In accordance with one aspect of the present invention, there is provided a screwdriver and comprising a hollow handle having a shank extending from a first end of the handle and a cap rotatably and removably engaged with a second end of the handle. A bit set is received in the handle and connected to the cap. The bit set has a central column and a plurality of clamping plates are radially connected to the central column so as to receive bits. A head member is connected to a first end of the central column and the head member is movably engaged with the inner periphery of the handle. A limit ring extends radially inward from an inner periphery of the handle and the head member will be stopped by the limit ring when the bit set is pulled from the second end of the handle. 
     The object of the present invention is to provide a screwdriver that includes a hollow handle with a slidable bit set received therein and the bit set has a head member connected thereto so that it is well supported during pulling from the handle. 
     These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded view to show a screwdriver in accordance with the present invention; 
     FIG. 2 is a perspective view to show the screwdriver of the present invention; 
     FIG. 3 is a side elevational view, partly in section, of the screwdriver, wherein a bit is connected to the shank of the screwdriver; 
     FIG. 4 is a side elevational view, partly in section, of the screwdriver, wherein a bit set is pulled from the handle of the screwdriver; 
     FIG. 5 is a perspective view to show the bit set and the screwdriver; 
     FIG. 6 is a side elevational view, partly in section, of the screwdriver, wherein another type of shank without ratchet mechanism is connected to the screwdriver; 
     FIG. 7 is an exploded view to show the screwdriver in accordance with the present invention and a light device mountable to the shank; 
     FIG. 8 is a side elevational view, partly in section, of the screwdriver, wherein the light device is mounted to a shank with a ratchet mechanism; 
     FIG. 9 is a side elevational view, partly in section, of the screwdriver, wherein the light device is mounted to a shank without a ratchet mechanism; 
     FIG. 10 is a perspective view to show another embodiment of the screwdriver that has another type of ratchet mechanism connected thereto, and 
     FIG. 11 is a perspective view to show yet another embodiment of the screwdriver wherein a universe joint is used to connect to the ratchet mechanism as shown in FIG.  10 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIGS. 1 to  3 , the screwdriver in accordance with the present invention comprises a hollow handle  10  having a shank  62  extending from a first end of the handle  10  and a cap  30  rotatably and removably engaged with a second end of the handle  10 . A bit set  20  is slidably received in the handle  10 . Two holes  12  are defined radially through the handle  10  and located close to the second end of the handle  10 , a limit ring  40  having two protrusions  41  extending radially outward therefrom is engaged with an inner periphery of the handle  10  so that the two protrusions  41  are engaged with the two holes  12 . The limit ring  40  extends radially inward from the inner periphery of the handle  10 . 
     A tube  14  is located longitudinally in the handle  10  and a plurality of plates  13  connected between the tube  14  and the inner periphery of the handle  10  so that the tube  14  is located in the handle  10  and located close to the first end of the handle  10 . The tube  14  has a closed end and an open end which communicates with the first end of the handle  10 . The tube  14  has a plurality of grooves  140  defined longitudinally in an inner periphery thereof. A first end  60  of a shank  62  is securely received in the tube  14 . The first end  60  of the shank  62  has a plurality of ridges  600  extending radially outward therefrom so that the ridges  600  are engaged with the grooves  140 . Accordingly, the shank  62  is co-rotatable with the handle  10 . A ratchet mechanism  61  is cooperated with the shank  62  and has a switch button  610  on an outside of the ratchet mechanism  61 . An access hole  150  is defined radially through the handle  10  close to the first end of the handle  10  so that the switch button  610  can be accessed via the access hole  150  by the user. A flange  70  extends radially outward from the shank  72  and the flange  70  is engaged with the first end of the handle  10 . A tubular member  100  is located in the first end of the handle  10  and the tubular member  100  has an inner threaded periphery. The shank  62  has a threaded section  71  which is engaged with the inner threaded periphery in the tubular member  100  to make sure that the flange  70  seals the first end of the handle  10 . An engaging hole  620  is defined in a distal end of the shank  62  so as to engage with a bit  24 . 
     The bit set  20  has a central column  22  and a plurality of clamping plates  230  are radially connected to the central column  22  so as to define a plurality of clamping recesses  23  that hold bits  24  therein. A head member  50  is connected to a first end of the bit set  20  and the head member  50  is movably engaged with the inner periphery of the handle  10 . The head member  50  has a recess  51  defined in an end thereof and the first end of the central column  22  is securely received in the recess  51 . Two slots  220  are defined radially through the first end of the central column  22  and two snap members  510  are located at an inside of the recess  51  of the head member  50  so that the snap members  510  are engaged with the slots  220 . The head member  50  has a shoulder portion  52  extending radially outward from an outside of the head member  50 . 
     A second end of the bit set  20  is rotatably connected to the cap  30  which has a skirt portion and two ribs  32  extend radially inward from an inner periphery of the skirt portion. A stepped block  31  extends from the inner periphery of the skirt portion of the cap  30  and is located between the two ribs  32 . The second end of the central column  22  is connected to a cup member  21  and has two slits  210  defined longitudinally therein. The two ribs  32  are engaged with the two slits  210 . A flexible hook  211  is defined between the two slits  210  and engaged with the stepped block  31  so that the cap  30  is rotatable independently from the handle  10 . The cup member  21  further has a stepped portion  213  that is engaged with the limit ring  40  when the bit set  20  is received in the handle  10 . As shown in FIGS. 4 and 5, the bit set  20  can be pulled from the second end of the handle  10  by pulling the cap  30  till the shoulder portion  52  of the head member  50  is engaged with the limit ring  40 . The bit set  20  is well supported because the head member  50  is engaged with the inner periphery of the handle  10 . A boss  214  extends radially outward from the stepped portion  213  of the cup member  21  so that when the bit set  20  is pushed into the handle  10 , the boss  214  is forced to move across an inner periphery of the limit ring  40  to notify the user that the bit set  20  is completely received in the handle  10 . 
     FIG. 6 shows that the shank  62  can be a general shank  62  that has an engaging hole  620  in a distal end thereof and has no ratchet mechanism. 
     FIGS. 7 and 8 shows that a light device  80  is securely mounted to the shank  62  and a sleeve  90  is rotatably mounted to the light device  80 . The light device  80  has batteries  84  received in recesses  83  in an outside of the light device  90  and two bulbs  86  are engaged with the light device  80 . Two curved notches  82  are defined in an end of the light device  80  and the sleeve  90  has two hooks  91  located in one end thereof so that the two hooks  91  are movably engaged with the two curved notches  82 . A lip  93  extends radially inward from the other end of the sleeve  90  to engage with the other end of the light device  80 . The sleeve  90  has a conductive plate  92  connected to an inner periphery thereof so that when rotating the sleeve  90  to contact the conductive plate  92  and the batteries  84 , the bulbs  86  turn on. FIG. 9 shows that the shank  62  has no ratchet mechanism cooperated therewith. 
     FIG. 10 shows that another type of ratchet mechanism  600  is connected to the handle  10  and FIG. 11 shows a universe joint  601  is used to connect to the ratchet mechanism  600 . 
     While we have shown and described various embodiments in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope and spirit of the present invention.