Abstract:
A component of a bit driving tool is presented, having a mid-chamber, telescopically received in an outer chamber. A bit storage chamber is formed in the mid-chamber, surrounding and rotatable about a central. A central rod extends through and out of the outer chamber. A dual lever arm comprising a first magnetic end and a second end is pivotably connected to the central rod such that the dual lever arm pivots into and out of axial alignment with the central bore. Telescopic extension of the mid-chamber out of the outer chamber positions the dual lever arm to magnetically connect with a rear end of a bit stored in the bit storage chamber and telescopic retraction of the component pivots the bit radially inwardly into the central chamber and wherein further telescope retraction of the component pushes the bit through the central chamber until the bit extends out of the component.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a component for a screw driver or drill that allows for ease of bit replacement. 
       BACKGROUND 
       [0002]    Drills and screwdrivers, both powered and manual are well known historically as tools for drilling holes and driving threaded screws into surfaces for any number of construction purposes. 
         [0003]    Although some manual screwdrivers and even drills are built with a single, integral screw or drill bit, it is more commonly preferred that the driver or drill be able to accommodate any number of bits, to allow for a variety of sizes of holes to be drilled, or a variety of sizes or types of screws to be driven. Bits are often stored in an external bit storage magazine from which a desired bit can be selected and loaded into the screwdriver or drill chuck. Alternately, many screw drivers comprise a bit storage magazine in the form of a hollow driver handle with multiple chambers for storing the bits. Bits can be selected and removed from the handle end and then loaded into the chuck end of the driver. 
         [0004]    The need to first remove and then load bits from an external or integrated magazine often leads to loss of bits and additional time. 
         [0005]    Some prior art drills and screwdrivers have been designed in which bits may be stored in chamber that is integral with the tool, and in which bits may be selected and then pushed through chamber and out through the chuck where it is locked or otherwise prevented from rotating inside or sliding out of the chuck. 
         [0006]    However in most such cases, the bit storage chamber is mis-aligned with the central chamber and chuck of the tool. In such cases, bit selection is performed by rotating the bit storage chamber until the desired bit alignes with an opening leading to the central chamber, and then the bit is pushed through the opening, into the chamber and out through the chuck. The arrangement is not unlike a bullet chamber in relation to the barrel of a gun. 
         [0007]    U.S. Pat. No. 7,086,314 teaches a tool with a bit storage chamber that is rotatable about a slotted, apertured core of the tool. The tool comprises a lever arm pivotally coupled to a core to magnetically attract the desired bit from the chamber and a magnet-tipped push rod to push the bit through a shaft to protrude through the chuck. The magnetic lever arm shares a limited area of contact with bit and is thus limited to the size of bits that can be magnetically attracted and pulled into the core. 
         [0008]    A need and interest therefore exists in the art to develop improved drill and screwdriver assemblies of simple internal design that allow for rapid changing of bits. 
       SUMMARY  
       [0009]    A component of a bit driving tool is presented. The component comprises a mid-chamber, telescopically received in an outer chamber, the mid-chamber and the outer chamber surrounding a central bore. A bit storage chamber is formed in the mid-chamber, surrounding and rotatable about the central bore and comprising one or more bit storage compartments. A central rod extends through and out of the outer chamber, said central rod being axially movable through central bore when the mid-chamber is telescopically retracted into the outer chamber. A dual lever arm comprising a first magnetic end; and a second end is pivotably connected to the central rod such that the dual lever arm pivots into and out of axial alignment with the central bore. Telescopic extension of the mid-chamber out of the outer chamber positions the magnetic end of the dual lever arm to magnetically connect with a rear end of a bit stored in the bit storage chamber and telescopic retraction of the component pivots the magnetic end and the magnetically connected bit radially inwardly into the central chamber and wherein further telescope retraction of the component pushes the central rod, the dual lever arm, the magnetic end and the bit axially through the central chamber until the bit extends out of the component. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    The present invention will now be described in greater detail, with reference to the following drawings, in which: 
           [0011]      FIG. 1  is a cross sectional view of the component of the present invention in an opened position; 
           [0012]      FIG. 2  is a cross sectional view of the component of the present invention in a bit engaging position; 
           [0013]      FIG. 3  is a cross sectional view of the component of the present invention in a closed position 
           [0014]      FIG. 4  is a side view of one embodiment of the magnetic end of the present invention; and 
           [0015]      FIG. 5  is a perspective view of one embodiment of the magnetic end of the present invention. 
       
    
    
     DESCRIPTION OF THE INVENTION 
       [0016]    The invention provides an insert or internal component for a screwdriver or drill. The component houses screw bits or drill bits that can be changed without the need to individually remove and load the bits into the tool opening. Changing of bits can be performed with the component installed in the screwdriver or drill. 
         [0017]    The component is rotatably received in the screwdriver or drill. More preferably, rotation of the component is accommodated by a series of ball bearings between the rotating component and the stationary outer drill body. When the component is in an open position, it can freely move or spin. When the component is moved to a closed position, it is locked against spinning unless the drill is activated. 
         [0018]    The term drill is used in the context of the present invention to generally describe any manual or powered tool used to drill holes or drive screws or other fasteners. For the purposes of the present invention the term drill is intended to encompass any such device that can handle standard fastener bits. The bits of the present invention can be drill bits or screwdriver bits, depending on the applications. Any number of sizes or shapes of such bits can be used with the component of the present invention. Most preferably the bits are 2″ bits. Shorter or longer bits can also be accommodated. 
         [0019]    The component of the present invention is shown in  FIGS. 1 to 3  in various positions. With reference to these figures, the component  2  comprises a mid-chamber  6  having first end that is telescopically received into a second end of an outer chamber  4 . When the mid-chamber  6  is extended out of the outer chamber  4 , it is rotatable. When the mid-chamber  6  is pushed into the outer chamber it is locked against independent rotation. Any number of known means may be employed to prevent relative rotation between the mid-chamber and the outer chamber  4 , including complimentary profiles on an inner surface of the outer chamber  4  and the on an outer surface of the mid-chamber  6  that interact to prevent relative rotation. Such profiles can include but are not limited to complimentary ribs and slots, ridges and valleys, or complimentary faceted surfaces. 
         [0020]    An inner chamber  10  sits inside both the mid-chamber  6  and the outer chamber  4 . The inner chamber does not rotate with the mid-chamber and is rotationally locked together with the outer chamber  4 . 
         [0021]    A central rod  8  extends through a central bore  24  of the component from the inner chamber  10  to the outer chamber  4  and extends out of and is rotationally locked to the first end of the outer chamber  4 . The portion of the central rod  8  that extends from the first end of the outer chamber  4  is connectable to a drill or other drive means to rotate the central rod  8  and thus cause rotation of the outer chamber  4 , inner chamber  10  and mid-chamber  6  when a bit has been engaged, the position shown in  FIG. 3 . 
         [0022]    A locking tip  18  extends from a second end of the mid-chamber  6  to receive bits  20 . The locking tip  18  can receive bits  20  that are pushed through the mid-chamber  6  or which are loaded, manually or otherwise, into a first end  22  of the locking tip  18 . 
         [0023]    The mid-chamber  6  comprises a bit storage chamber  26  that circumferentially surrounds the inner chamber  10  and a central bore  24  of the component  2 . The bit storage chamber  26  comprises one or more spaces for housing one or more bits  20 . Rotation of the mid-chamber  6  rotates the bit storage chamber  26  around the central bore  24  for selection of a desired bit  20 . A longitudinal slot  28  in the central bore  24  allows for passage of a desired bit  20  from the bit storage chamber  26  into the central bore  24 . 
         [0024]    The second end of the mid-chamber  6  preferably comprises an angled profile  16  that assists in guiding bits  20  into the radial center of the component  2  and out of the locking tip  18 . 
         [0025]    The inner chamber  10  further comprises a dual lever arm  30 . The dual lever arm  30  comprises a first pivot point  36 , axially aligned with the central bore  24 , and pivotably connecting the dual lever arm  30  to the central rod  8 . The dual lever arm  30  further comprises a magnetic end  32  that is aligned with the longitudinal slot  28 . Preferably the magnetic end is pivotable by means of a second pivot joint  34 . The magnetic end  32  and the second end  38  are opposite one another and pivot radially towards and away from the central bore  24  of the component  2 , about first pivot point  36 . 
         [0026]    With reference to  FIG. 1 , to load a bit  20 , the mid-chamber  6  is telescopically extended from the outer chamber  4 , thereby allowing rotation of the mid-chamber  6 , independent of the outer chamber  4  and the inner chamber  10 . Bit selection is made by rotation of the mid-chamber  6 , thereby rotating the bit storage chamber  26  about the central bore  24  until the desired bit  20  aligns with slot  28 . 
         [0027]    Preferably the component  2  of the present invention comprises means for the user to identify and select a bit  20  of choice. In one embodiment, the mid-chamber  6  can be made of a transparent or translucent material that allows visual identification of the bits within the bit storage chamber  26 . In another embodiment, an audio, visual or tactile means can be used to confirm alignment of the desired bit  20  with the slot  28 . For example, a detent can be incorporated into mid-chamber  6  that provides a tactile or audio ‘click’ or ‘snap’ each time a bit storage space is aligned with the slot  28 . It would be well understood by a person of skill in the art that any number of means can possibly be used to identify a desired bit or to confirm alignment of said bit  20  with slot  28 . 
         [0028]    In a further preferred embodiment, mid-chamber  6  can be a removable piece of the present invention, allowing for different mid-chambers, each having its own bit storage chamber with one or more bits, to be loaded into to drill component  2  in order to provide different bits for use with the present invention. 
         [0029]    The magnet end  32  of the dual lever arm aligns with the bit storage chamber  26 . Preferably, the dual lever arm  30  comprises a biasing means  42  for biasing the magnetic end  32  of the dual lever arm  30  to the bit storage chamber  26  rather than the central bore  24 . More preferably the biasing means  42  comprises a biasing spring at the first pivot point  36  and mating shoulder  14  on the central rod  8 . 
         [0030]    When the desired bit is aligned with the slot  28 , the magnetic end  32  of the dual lever arm  30  becomes magnetically attracted to a proximal end of the bit  20  and thereby catches the bit  20 . In a further preferred embodiment, as illustrated in  FIGS. 6 and 7 , the magnetic end  32  may optionally include a protrusion  40  that may serve to mechanically engage the bit  20 , in addition to the magnetic engagement provided by the magnetic end  54 . 
         [0031]    The mid-chamber  6  can then be retracted into outer chamber  4 . A first stage of this retraction is shown in  FIG. 2 , which illustrate an engaged position of the component  2  of the present invention. In the engaged position, at least partial retraction of the mid-chamber  6  into the outer chamber  4  causes the central rod  8  to travel axially in the direction of the locking tip  18 . The second end  38  of the dual lever arm correspondingly travels along shoulder  14 , thereby overcoming the biasing force of biasing means  42  and causing the dual lever arm  30  to pivot about first pivot point  36 . Rotation of the dual lever arm about first pivot point  36  causes magnetic end  32  of the dual lever arm  30 , with bit  20  attracted thereto, to pivot into alignment with the central bore  24 , thus pulling the bit  20  through slot  28  and into central bore  24 . The optional protrusion  40  on the magnetic end  32  may preferably serve to assist in engaging and guiding the bit  20  through the central bore  24 . 
         [0032]    Optionally a second pivot point  34  is present at the magnetic end and serves to maintain alignment of the magnetic end  32  with a rear end surface of the bit  20 , thereby maximizing contact and magnetic attraction between the magnetic end  32  of the dual lever arm  30  and the bit  20 . 
         [0033]    As the mid-chamber  6  is retracted into the outer chamber  4 , the central rod  8  continues to travel axially into central bore  24 , thereby also pushing dual lever arm  30  with the bit  20  magnetically linked to the magnetic end  32 , through the central bore  24 . The component  2  is illustrated in its fully engaged position in  FIG. 3 , in which the bit  20  has been pushed through the central bore  24  and out to the locking tip  18 , from which the bit  20  protrudes. The locking tip  18  preferably comprises locking means  46  (not shown) for preventing the bit from rotating within the locking tip  18  or from falling out of the locking tip  18 . 
         [0034]    In use, the central rod  8  is connected into a drill or similar driver device. Rotational force powered by the driver device is transmitted to the central rod  8 . The central rod  8  is rotationally fixed to the outer chamber  4 , which is in turn rotationally fixed to the inner chamber  10  and to mid-chamber  6 . The mid-chamber  6  is further rotationally fixed to the locking tip  18 , which is rotationally fixed to the bit  20 , thereby serving to transmit rotational force from the driver device to the bit  20  and effect drilling or fastening as needed. 
         [0035]    A bit  20  can also be retracted from the locking tip  18  and returned to its space in the bit storage chamber  26  by reversing the method described above. Namely, the mid-chamber  6  is protracted out of the outer chamber  4 , thereby retracting the central rod  8 , dual lever arm magnetic end  32  and bit  20  back through the central bore  24 . As the second end  38  of the dual lever arm  30  moves past shoulder  14 , the biasing means  42  forces the second end  38  and the magnetic end  32  of the dual lever arm  30  to move radially outwardly, in opposite directions. The magnetic end  32 , still magnetically linked to the bit  20 , moves the bit  20  from the central bore  24  through slot  28  and back to its space in the bit storage chamber  26 . 
         [0036]    It is also possible to load bits into the locking tip  18  from sources other than the insert  2 . Bits  20  can also be loaded into the first end  22  of the locking tip  18 , in which case the same locking means  46  cooperate to hold the bit  20  from falling out. This method of loading advantageously allows the present component  2  to be used with a variety of bits  20  beyond those stored in the component  2 . 
         [0037]    The present invention can thereby accommodate bits in the locking tip  18  which may be significantly larger than those that can be accommodated in the bit storage chamber  26 . Preferably the bit storage chamber  26  accommodates bits  20  of up to a 2″ size, whereas bits of sizes ranging from 2″ up to 4″ can be inserted from outside into the locking tip  18 . 
         [0038]    The bit storage chamber  26  of the present invention can advantageously be emptied and filled by the user, to load the component  2  with a desired magazine of bit types and sizes. To empty spaces in the bit storage chamber  26 , the user simply loads bits  20  through the locking tip  18 , as described above, and pulls the bits  20  out of the locking tip  18  to empty the bit storage chamber  26 . Then new bits  20  can be inserted into the locking tip  18  and the component  2  can be protracted to its open position to pull the bits  20  back into the bit storage chamber  26 . 
         [0039]    In the foregoing specification, the invention has been described with a specific embodiment thereof; however, it will be evident that various modifications and changes may be made thereto without departing from the broader scope of the invention.