Patent Publication Number: US-7591616-B1

Title: Drill bit holder attachment

Description:
PRIORITY DATE CLAIMED 
   None. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   In general the novel invention is directed to an improved structure for a portable drill bit storage rack wherein drill bits are inserted for storage between uses. The overall drill bit storage rack is provided with a frictional engagement sleeve that retains the bits in a single row but which allows selective removal of a drill bit from the storage rack. In particular, the present invention relates specifically to an ergonometrically improved tool bit holder and presenter apparatus that stores bits side-by-side. 
   2. Description of the Prior Art 
   Workers, especially electricians, must often work in areas in which it is difficult to get to a tool chest. These same workers, however, must often perform a variety of functions, each requiring a different tool or a different tool bit. Workers, therefore, generally carry a multiplicity of tools in a tool belt or tool kit. Even the most skilled worker, however, looses time removing and inserting tool bits in his belt. Workers also loose time searching for lost tools that they have set down at different locations. Furthermore, a tool belt with all the necessary tools can become quite disorganized leading to increased worker fatigue and more inefficient use of time. It is desirable, therefore, to have a single tool bit holder that can be detachably affixed to a power drill or other power hand tool that utilizes different bits. Prior art attempts at providing such a bit holder resulted in a structure that made it difficult to grasp individual bits because the bits were arrayed in a matrix or in a circular pattern around a chuck. This arrangement makes it difficult to grasp a bit with two opposing fingers and remove it. In addition, the circular arrangement as well as arrangements that have individual apertures and holes in which to insert bits after use are cumbersome to use and difficult for a worker wearing work gloves to efficiently insert the bits. 
   U.S. Pat. No. 4,973,205, which issued to Spaulding on Nov. 27, 1990 provides a bit holding apparatus wherein a hand drill includes a conventionally configured elongate housing with an elongate orthogonally extending handle relative thereto, with a forwardly mounted collet to receive drill bits therewithin. The apparatus further includes a transparent drill bit housing pivotally mounted to an upper surface of the central housing body of the drill formed with a snap-fit cover to receive drill bits in a convenient and accessible manner. A bifurcated chuck-key holder includes resilient legs defining a slot to resiliently secure a chuck-key therewithin. 
   On Jul. 30, 1991 U.S. Pat. No. 5,035,553 issued to Lo for an improved drill bit storage rack which allows for the user to insert the drill bit into the drill bit storage rack by grasping the handle portion of the drill bit. In this manner, the user&#39;s hand is protected by holding the drill bit by the handle portion and not being either cut or burned by grasping the drill bit blade. The two major drawbacks with this structure are that it is difficult to identify the bit needed when retrieval is necessary and nowadays workers use work gloves to protect their hands. 
   On Jun. 22, 2004 Wadsworth further advanced the art with U.S. Pat. No. 6,752,268 for a magnetically holdable drill bit. This patent teaches an invention to provide a quick-change tool element wherein at least two or more working tools are simultaneously attracted, held and served by a magnet to prevent loss of tool bits from the chuck of a hand drill where the grip of the jaws has somewhat slackened. Wadsworth brings a magnetized bit into contact with the interior of the drill, while simultaneously holding a screw or other object by magnetism at the other, exposed end of the tool element. A few weeks later on Jul. 13, 2004 Beauchamp received U.S. Pat. No. 6,761,095 for a bit holder arrayed circularly around the drill shaft. The Beauchamp bit holder is (a) a shaft adapted at one end for releasably mounting to the drill chuck, and at the other end for releasably mounting tool bits therein; and, (b) a circular storage rack for releasably storing tool bits in a nested fashion around the shaft such that the drill shaft and the nested storage rotate in unison with the drill chuck. 
   U.S. Patent Publication 0139831 published on Jul. 22, 2004 by Nagy teaches a tool for housing and supplying bits through an elongated tube of a screw driver or drill to a forward presentation for use. The housing has a rotatable storage holder mounted in the housing for holding and storing a plurality of tool bits and arranged by manual engagement with an exposed side portion to rotate about a second axis parallel to the tube. The rotatable holder has a plurality of receptacles each for receiving a respective one of the tool bits arranged parallel to the second axis and in angularly spaced relation around the second axis. 
   OBJECTS OF THE INVENTION 
   A primary object of the invention is to provide a receptacle and for receiving a single line linear array of bits wherein each bit can be inserted anywhere in the receptacle with two opposite fingers without having to line up the bit to a particular hole or aperture. 
   It is another object of the present invention to provide a bit presenter for presenting a single line linear array of bits wherein each bit can be grasped with two opposite fingers and removed without interference from surrounding bits. 
   It is still another object of the present invention to provide a portable drill bit receptacle for frictionally holding a plurality of bits wherein the receptacle frictionally and releasably engages a slot in the portable drill shaped to receive the receptacle. 
   It is yet another object of the present invention to provide a novel structure for a single hole in a holder that enables the single hole to receive and frictionally engage a plurality of bits without the usual prerequisite of having to line up each bit to an individual receiving hole. 
   Other objects of this invention will appear from the following description and appended claims, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views. 
   SUMMARY OF THE INVENTION 
   The novel structure embodying the teachings of the present invention enables a portable drill bit holder and drill bit presenter to be detachably mounted by frictional engagement in a slot formed in the body of a hand drill. The holder is made of a resilient material such as a hard rubber or TEFLON® plastic, for example. The holder has an elongated oval shaped hole of a fixed depth with a bottom and with two parallel elongated side walls spaced apart a separation distance slightly less than the highest diameter of the plurality of bits to be received in the holder. Inside the hole and lining the wall of the hole is a resilient tube having a length approximately equal to the fixed depth of the hole. The resilient tube is spongy and has a thickness equal to slightly less than one-half of the separation distance between the two parallel elongated side walls. The tube is disposable and replaceable. After the tube is worn by insert and removal of bits between the inside walls thereof and the frictional engagement of the bits by the inside walls, it is designed to be replaced. The tube is held in place by frictional engagement with the side wall of the hole and/or use of an adhesive to bond the tube to hole. Bits are held in place in between the spongy resilient inside wall of the tube. When inserted into the hole the inside wall of the tube is almost pressed together. A slight opening is left to facilitate easy insert of the bits into the holder. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features, aspects, and advantages of the present invention will become better understood with regard to the following detailed description of a preferred embodiment, appended claims, and accompanying drawings wherein: 
       FIG. 1  is a detailed perspective view showing a preferred embodiment of the invention; 
       FIG. 2  is a perspective view of the novel tool shown in  FIG. 1  with the tool bits shown in  FIG. 1  removed; 
       FIG. 3  is a top view of the embodiment shown in  FIG. 2 . 
       FIG. 4  is another detailed cross-sectional view of the novel invention taken along the plane  4 - 4 ′ shown in  FIG. 2 ; 
       FIG. 5  is a perspective view of a resilient tube insert for the novel invention; 
       FIG. 6  is a detailed bottom view of the novel invention shown in  FIGS. 2 and 8 ; 
       FIG. 7  is a side view of the novel invention shown in  FIGS. 2 and 8 ; 
       FIG. 8  is a perspective view of another embodiment of the novel invention; 
       FIG. 9  is a top view of the embodiment of the novel invention shown in  FIG. 8 ; 
       FIG. 10  is a perspective of the novel invention holding various bits and mounted in a horizontal slot on a hand drill; 
       FIG. 11   a  is a perspective view of a drill with a novel improvement to the casing; and, 
       FIG. 11   b  is a front view of the novel improvement in the drill shown in  FIG. 11   a.    
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   In  FIG. 1  there is shown a first preferred embodiment of a novel tool bit holder  10 . The tool bit holder  10  forms a detachably mountable hand drill bit holder and static presenter apparatus. The apparatus is oblong and made of a compressible flexible resilient material such as rubber, silicone rubber, or plastic, for example. The holder  10  has a tab  12  in the form of a protrusion formed as an integral extension of a bottom of the holder  10 . The tab  12  is shaped to tightly fit into a rectangular slot  14 , for example, formed in a hand drill  16  such as shown in detail in  FIG. 10 , for example. The holder  10  has first and second parallel walls  18  and  20 , respectively, formed inside the holder  10 . The two parallel walls  18  and  20  are joined at each end by two opposing first and second semi-circular walls  22  and  24 , respectively, to form a tubular surface interior to the holder  10 . Inside the tubular surface formed by the surfaces  18 ,  20 ,  22 , and  24  there is a thick walled tube  30 . The tube  30  has a wall thickness D. The parallel walls  18  and  20  are separated by a distance S. Twice the wall thickness D is selected to be slightly less than the separation distance S. The surface inside the holder  10  forms a blind hole  32 . When the tube  30  is inserted into the blind hole  32 , the walls of the tube  30  conform and become oval and oblong. 
   In  FIG. 1 , the set of bits  34  is shown inserted into the holder  10  and gripped between the inner walls  36  and  38  of the tube  30 . The tube  30  has an outside surface  40  as shown in  FIG. 5 . The tube  30  is made of highly compressible large cell rubber such that the inner surface of the tube  30  grips the bits  34 . The tube  30  is gripped sufficiently by the walls  18  and  20  to stay in place in the blind hole  32  of the holder  10 . The holder  10  with the tube  30  in place and without bits  34  inserted is shown in  FIGS. 2 and 3 . 
   A cross-section of the holder  10  with the tube  30  inside is shown in  FIG. 4 . The cross-section in  FIG. 4  is taken along the plane  4 - 4 ′ illustrated in  FIG. 2 . In the cross-section there is shown the tube  30  pressed together to form a slot  42  into which bits such as bits  34  may be inserted. The mouth of the slot  42  is rounded to ease insertion of bits therein. 
   An alternative embodiment of the invention is shown in  FIGS. 8 ,  9 , and  10 . There a plurality of apertures  44 , either round or hexagonal, is aligned in a single row. The apertures  44  are each sized for specific bits, each aperture  44  being of slightly smaller size so that each matching bit has to be forced into its individual hole for substantial frictional engagement therein. The substantial frictional engagement insures that each bit is retained in its aperture  44  despite substantial vibration from the hand tool or drill.  16  being operated while the bits are stored in the holder. 
   Moreover, it is an essential feature that this second embodiment has the novel tab  12  for substantial frictional engagement in the slot  14  as shown in  FIG. 10 . The depth and width of the slot  14  are selected to insure that the novel tab  12  is substantially retained in the slot  14  when the drill  16  is operated with its most severe vibrations, and yet allow the tab  12  to be released only when it is manually pulled away from the drill  16 . The crux of this second embodiment is the novel addition of a releasable frictional engagement tab  12  to a linear bit holder  10 ′ for the substantial frictional engagement of the tab  12  in a congruent mated slot  14  formed anywhere in the body of the drill  16 , for example as shown in  FIG. 10 . 
   The apertures  44  are shown round in shape. For example, the diameter of an aperture for a particular hexagonal bit is made slightly less than the distance between opposite corners of an hexagonal bit to provide a firm frictional engagement of that bit in the assigned receiving aperture  44 . 
   Referring to  FIGS. 11   a  and  11   b  there is shown the slot  14 . The slot  14  is a novel improvement in the power hand drill  16 . The slot  14  provides an affixing means for affixing the holder  10  as shown in  FIG. 1  to the hand drill tool  16 . The holder  10  is attached to the slot  14  in the hand drill tool  16  by inserting the tab  12  made of a resilient compressible flexible material such as rubber, TEFLON® plastic, or NYLON™ plastic, for example. The hand drill  16  has an electrical motor  46 , a chuck  48  adapted to receive a tool bit  50  selected from the plurality of bits  52  (See  FIG. 10 ), and a molded outer body or casing  54 . 
   As shown in  FIG. 4 , the first and second opposing walls  60  and  62 , respectively, of the tube  30  when inserted are separated by the spacing  64 . The separation S is equal to twice the thickness D plus the spacing  64 . 
   The parameters S, D, and  64  are determined by the upper and lower limits of the diameters of a set of bits to be held in the holder  10 . Another factor is the modulus of compression of the material used for the tube  30  and the holder  10 . For the holder to effectively frictionally engage a set of bits with diameters ranging from B 1  to B N  where N equals the number of bits in the set, then if B 1  is less than B N , the maximum compression of the two walls  36  and  38  of the tube  30  should be equal to or greater than B N . Hence, the compressibility of the material for the tube  30  is selected to be about 50% and the parameter or distance D is equal to or greater than ½ of B N . The parameter  64  should be in range of ½ to ⅓ of B 1 . With these parameters based in this manner on the diameters of the bits to be held and presented, the need for specific holes for specific bits is eliminated and the oblong aperture or blind hole  32  with the tube  30  inserted can accommodate a plurality of bits  34  having diameters extending over a range without the need to have specific holes or bins for specific bits. 
   The detachably mountable hand drill tool bit holder and static presenter apparatus shown in  FIG. 1  is adapted to receive the plurality of variously sized bits  34  for use with the hand drill tool  16  shown in  FIG. 11   a . The plurality of variously sized bits  34  have diameters that extend over a fixed range. The fixed range is from a small diameter, e.g. 0.5 cm., to a large diameter, e.g. 3.0 cm. Thus, each bit  34  has a diameter in the fixed range. The novel holder  10  is designed and adapted as shown and made out of the compressible resilient flexible material to firmly hold and present the bits  34  for use while frictionally engaged and attached within the novel adaptive slot  14  of the hand drill tool  16 . The slot  14  may be oriented vertically or horizontally or at any angle anywhere on the drill  16  by forming the slot  14  in the outer casing  54 , for example. 
   The hand drill tool  16  with the affixing means for affixing the holder  12  to the hand drill tool  16  allows the holder to be attached to the drill tool  16  and forms the holder  12  into a tool bit presentment means for presenting each tool bit  34  with two opposing sides exposed and unobstructed for improved accessibility by a user wearing work gloves, for example. The tab  12  forms an integral frictional engagement means for detachably connecting the holder  10  or apparatus to the affixing means or slot  14 . Referring to  FIG. 1 , the blind hole  32  has the tube  30  therein that forms a frictional bit engagement means for releasably holding anywhere in the blind hole  32  all of the plurality of bits  34 . The blind hole  32  is located in holder  10 . The holder  10  forms the detachably mountable hand drill tool and static presenter apparatus of the novel invention. The holder  10  or tool presentment means is integrally connected to the slot  14  or integral frictional engagement means. 
   The blind hole  32  as shown in FIGS.  1 , 2 , 3  and  4  has an oval or oblong elongated cross section. The blind hole  32  is formed by first and second parallel elongated opposing side walls  18  and  20  separated by a first distance S. Shown in  FIG. 4 , a distance  64  representing a separation of the walls  60  and  62  shown in  FIG. 3  is less than the small or smallest diameter B 1  in the fixed range of diameters that range from diameter B 1  to diameter B N  corresponding to the diameters of the bits  34  as shown in  FIG. 1 . A thick walled tube  30  inside the holder  10  forming the novel apparatus is preferably made entirely of a substantially compressible resilient flexible material such as medium hard rubber. Hard medium cell rubber is molded to form a unitary structure. As shown in FIGS.  3 , 4 , and  5  the inside walls  60  and  62  are compressible, resilient and flexible to a degree where both inside walls having the thickness D can be compressed to the point that the spacing  64  between the parallel side walls  60  and  62  equals a second distance whereby the second distance is equal to the large or largest bit having a diameter B N . 
   As this invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, the present embodiment is, therefore, illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that fall within the metes and bounds of the claims or that form their functional as well as conjointly cooperative equivalent steps are, therefore, intended to be embraced by those claims. 
   
     
       
         
             
           
             
                 
             
             
               PARTS LIST 
             
             
                 
             
           
          
             
                 
             
          
         
         
             
             
             
          
             
                 
               tool bit holder 
               10 
             
             
                 
               tab 
               12 
             
             
                 
               rectangular slot 
               14 
             
             
                 
               hand drill 
               16 
             
             
                 
               first parallel wall 
               18 
             
             
                 
               second parallel wall 
               20 
             
             
                 
               first opposing semi-circular wall 
               22 
             
             
                 
               second opposing semi-circular wall 
               24 
             
             
                 
               thick walled tube 
               30 
             
             
                 
               wall thickness 
               D 
             
             
                 
               separation distance 
               S 
             
             
                 
               blind hole 
               32 
             
             
                 
               variously sized bits 
               34 
             
             
                 
               diameter 
               B 1   
             
             
                 
               diameter 
               B N   
             
             
                 
               number of bits in set 
               N 
             
             
                 
               first inner wall 
               36 
             
             
                 
               second inner wall 
               38 
             
             
                 
               outside surface 
               40 
             
             
                 
               slot 
               42 
             
             
                 
               plurality of apertures 
               44 
             
             
                 
               electrical motor 
               46 
             
             
                 
               chuck 
               48 
             
             
                 
               tool bit 
               50 
             
             
                 
               plurality of bits 
               52 
             
             
                 
               casing 
               54 
             
             
                 
               first inside wall 
               60 
             
             
                 
               second inside wall 
               62 
             
             
                 
               spacing 
               64