Abstract:
An improved two-ended reversible drill/driver tool for use with power drills. The tool having a hollow cylindrical socket that at one end has a drive shank for insertion into a chuck of a powered drill, and, at the opposite end, has a polygonally shaped opening therein for receiving a correspondingly shaped, two-ended, reversible tool assembly. This tool assembly is sized to slide within the hollow socket, and has a combined drill bit and countersink at one end, and, at the other end, a polygonally shaped opening for accepting a screw driver bit having a shank with a polygonal cross section.

Description:
This application is a continuation of application Ser. No. 08/439,355 filed May 11, 1995 now U.S. Pat. No. 5,779,404, which was a continuation-in-part of application Ser. No. 08/236,992 filed May 2, 1994, now U.S. Pat. No. 5,470,180. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates to an improved tool for use with a powered drill. The tool includes a two-ended reversible tool assembly with one end having a bit for drilling a pilot hole and countersink, and the other end having a screwdriver for driving a screw into the pilot hole. 
     Presently, carpenters and other builders often use a combination of tools to accomplish the task of drilling and countersinking pilot holes for screws and then driving a screw into the pilot hole. Generally, they either have used two powered drills with one holding a pilot-hole, drill-bit attachment and the other holding a screwdriving attachment, or they have used one drill in which the separate attachments were alternately clamped into the chuck of the single drill with a corresponding waste of time. 
     There have been several previous attempts to solve the problem of maintaining two attachments available for use in one tool clamped in a powered drill. U.S. Pat. No. 3,023,015 to Pankow illustrates an elongate tubular cylindrical dual socket having a drill chuck engaging tang at one end. The other end of the socket is designed to releasably hold reversible screwdriver and countersink attachments. This socket accommodates only specially manufactured bits, both for the screwdriver and the countersink attachments, each having a lateral stop flange to limit insertion depth into the socket. The bits are held in place with set screws. A ball detent device positioned on the socket is used to transmit rotational energy from the drill to a bit. Transmitting rotational energy in this fashion through the sloping walls of a bail in a detent puts considerable deforming strain on the socket. A guide sleeve is also provided to cover the ball detent device. A pair of exposed springs attached to the sleeve resiliently holds the sleeve on the socket. 
     U.S. Pat. No. 4,676,703 to Swanson also illustrates a reversible drill bit and drive tool holder. The reversible drill and driver tool holder pivotally holds the dual ended socket for holding the reversible tools. The bits are held in place in the socket with set screws. The tool holder is machined to receive the particular tool not being used in a Position within the holder so as to be out of the way. A user pivots the socket within the tool holder to position the apropriate tool against the work piece. 
     From the above, it can be seen that a need exists for a simple two-ended reversible tool assembly for use with a powered drill. The reversible tool socket should be capable of accepting a wide variety of screw driving bits and should also be capable of transmitting rotational energy from the drill to the bit without being subject to wear. 
     Further, there are widely-available commercial screw driver bits having hexagonal shanks. These bits are used by carpenters and builders with drill sockets having a corresponding hexagonal shape. These bits are commonly used today as replacement bits thereby eliminating the necessity of replacing the entire screwdriver. A need exists for a reperssible bit drill attachment capable of accepting these conventional hexaconal shanked bits. 
     SUMMARY OF INVENTION 
     The present invention relates to an improved two-ended reversible drill/driver tool for power drills. The reversible drill/driver tool has a hollow cylindrical socket that at one end has a drive shank for insertion into a chuck of a powered drill, and at the opposite end has a polygonally shaped opening therein. 
     A separate, two-ended, reversible tool assembly, sized to slide within the hollow socket, has a combined drill bit and countersink at one end, and at the other end a polygonally shaped opening for accepting a screwdriver bit having a shank with a polygonal cross-section. The countersink is a conventional countersink and may have a relief section for chip removal. A magnet attached to the reversible tool assembly is placed adjacent the polygonally shaped opening at the opposite end from the countersink to magnetically hold the screwdriver bit in the reversible tool assembly. With this arrangement, the screwdriver bit can easily be pulled away from the magnet to be replaced with another bit. 
     To prevent rotation of the tool assembly within the socket, a portion of the tool located intermediate the ends of the reversible tool assembly has a polygonally shaped exterior surface. This polygonally shaped surface mates with a similarly shaped interior surface of the hollow socket. These surfaces permit rotary motion to be transmitted by the drill, through the drive shank, through the socket, to an exposed attachment. Further, this drive arrangement between the socket and the tool holder minimizes the deforming, rotational strain on the socket when the drill is operated. 
     To prevent the reversible tool from inadvertently slipping out of the socket, the reversible tool assembly is releasably locked to the hollow socket using a ball removeably positioned in a locking groove. A hollow cylindrical sleeve, slideably surrounding the outer surface of the socket, is used to removeably position the ball in the locking groove. When the sleeve is moved toward the drive shank the ball is positioned in the locking groove. When the sleeve is moved toward the exposed bit end of the socket the ball may be removed from the locking groove by pulling the reversible tool out of the socket. The sleeve freely rotates on the socket and can be held with one hand while operating the powered drill with the other. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In order that the invention may be clearly understood and readily carried into effect, a preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings wherein: 
     FIG. 1 is an elevational view of an elongate reversible drill/driver tool of the present invention; 
     FIG. 2 is a cross-sectional view along a line  2 — 2  in FIG. 1; 
     FIG. 3 is an elevational of a two-ended reversible tool assembly; 
     FIG.  4   a  is an enlarged cross-sectional view along a line  4 — 4  in FIG. 1 illustrating a locking mechanism for the two-ended reversible tool assembly with a sleeve positioned in an unlocked position; 
     FIG.  4   b  is the same cross-section view as FIG.  4   a  with the sleeve moved to a locked position; 
     FIG. 5 is an end view of the right end of the elongate reversible drill/driver tool shown in FIG.  1 . 
     FIG.  6   a  is an enlarged cross-sectional view of a second embodiment along a line  4 — 4  in FIG. 1 illustrating a second locking mechanism for the two-ended reversible tool assembly with a sleeve positioned in an unlocked position; 
     FIG.  6   b  is the same cross-section view as FIG.  6   a  with the sleeve moved to a locked position; and 
     FIG. 7 is locking spring used in the second embodiment shown in FIG.  6   a  and  6   b.   
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     A preferred embodiment of the reversible drill/driver tool  10  is shown in FIG.  1 . The elongate reversible drill/driver tool  10  has a hollow socket  12  which has a drive shank  14  at one end to be received by a chuck of a powered drill. At the other end, hollow socket  12  has a polygonally shaped first opening  16  for slideably receiving two-ended, reversible tool assembly  18 . 
     The reversible tool assembly  18  has a conventional countersink and drill bit  20  at one end that is used for boring pilot holes in a workpiece, although other tools including other screwdriver bits could be inserted equally as well. At the other end reversible tool assembly  18  has a conventional screw driver bit  22  with a shank that has a polygonal cross-section  24 . In the drawings, the screw driver bit  22  is illustrated as a Phillips head screw driver, but any other screw driver bit, such as a straight blade, Allen wrench, or other socket driver having a polygonal cross-section, could be used equally as well. 
     A generally circular cross-section central body  26  holds countersink and drill bit  20  on one end and screw driver bit  22  at the other end. Body  26  has a polygonally shaped second opening  28  at one end, which in the preferred embodiment is a hexagonal shape as best seen in FIG.  5 . Opening  28  is sized to accept a screw driver bit  22  that also has a similar polygonally shaped cross-sectional shank  24 . A magnet  30  is attached to body  26  adjacent second polygonally shaped opening  28  to hold a screw driver bit  22  inserted into the opening. Although body  26  has a generally circular cross-section shape, a polygonally shaped portion  32  is formed on body  26  intermediate the ends thereof and sized to slide through a mating polygonally shaped first opening  16 . Polygonally shaped portion  32  of body  26  mates with polygonally shaped first opening  16  of socket  12  to prevent tool assembly  18  from rotating inside hollow socket  12 . The mating of body  26  with socket  12  assures a positive, non-rotational match between two mating parts and avoids placing deforming strain on the tool retaining socket  12  when the drill is operated to rotate the tool. Rotary motion transmitted from drive shank  14  to screw driver bit  22  is transmitted through the polygonally shaped mating surfaces. 
     As best seen in FIGS.  4   a  and  4   b , socket  12  is provided with a tapered hole  42  to receive a detent ball  36 . The interior opening of hole  42  is sized to have a diameter smaller than the diameter of detent ball  36  to prevent detent ball  36  from dropping out of hole  42 , but sufficient large to allow a portion of detent ball  36  to extend outwardly beyond hole  42 . 
     A groove  34  is cut in polygonal shaped portion  32  of reversible tool assembly  18 . This groove is sized to removeably receive the portion of detent ball  36  extending outwardly beyond hole  42 . With the detent ball  36  held in groove  34 , as explained below, the reversible tool assembly  18  is prevented from inadvertently slipping out of socket  12 . 
     A cylindrical sleeve  38  is fitted around socket  12 . This sleeve is provided with an interior angular groove  50 . As best seen in FIGS.  4   a  and  4   b , when groove  50  is positioned over detent ball  36  (FIG.  4   a ), the detent ball  36  can move into groove  50 . This enables a user to remove the tool assembly  18  from socket  12 . When groove  50  is not positioned over detent ball  36  (FIG.  4   b ), the detent ball  36  is held in groove  34 , and tool assembly  18  is prevented from being removed from socket  12 . 
     As seen in FIGS.  4   a  and  4   b , socket  12  is further provided with an annular retaining ring groove  40  encircling socket  12  on an exterior surface. A retaining ring  44  is positioned in retaining ring groove  40 . Sleeve  38  is also provided with two spaced apart annular grooves  46  and  48 . When sleeve  38  is slid away from drive shank  14 , retaining ring  44  springs radially outward from socket  12  into groove  46  in sleeve  38 . Groove  46  is positioned to have groove  50  positioned over detent ball  36  so that tool assembly  18  can be removed (FIG.  4   a ). When sleeve  38  is slid toward drive shank  14 , retaining ring  44  springs radially outward from socket  12  into groove  48 . Groove  48  is positioned to have the groove  50  not positioned over detent ball  36 , so that the detent ball  36  is moved into groove  34  of tool assembly  18  to lock tool assembly  18  within socket  12  (FIG.  4   b ). 
     An alternate embodiment of a releasable retaining means is shown in FIGS.  6   a  and  6   b . A shaped cylindrical sleeve  38   a  again surrounds hollow socket  12 . Sleeve  38   a  is constrained to slideably move longitudinally on socket  12 . A “C” shaped hook spring  52 , constructed of resilient material for example spring steel, is provided as shown in FIG. 7 with a hook  54  at one end used to lock the reversible tool assembly  18  in place. In a preferred embodiment of this alternative embodiment, a single hook  54  is provided at one end of the “C” shaped hook spring  52 , although hook spring  52  could as easily have double hooks, one located at either end of the “C” shaped hook spring so that both hooks could lock the reversible tool assembly  18  in place. Resilient “C” shaped hook spring  52  is biased to spring radially outwardly after being compressed. 
     Hollow socket  12  has a hole  42   a , which extends through a wall of socket  12  from the exterior to the interior of the socket. Hole  42   a  is sized to slideably accept hook  54  of “C” shaped hook spring  52 . In addition, a loading groove  55  is provided on socket  12  adjacent hole  42   a  into which hook spring  52  can be compressed as cylindrical sleeve  38   a  is slipped over hook spring  52  during initial assembly of tool  10 . 
     Cylindrical sleeve  38   a  has a recessed interior camming surface  58  into which hook spring  52  can expand outwardly as shown in FIG.  6   a  so that reversible tool assembly  18  can be removed. Cylindrical sleeve  38   a  has a second recessed interior camming surface  60  which compresses spring  52  as sleeve  38   a  is moved across spring  52  to force hook  54  through hole  42   a  and into intermediate groove  34  as shown in FIG.  6   b . With hook  54  positioned in intermediate groove  34 , reversible tool assembly  18  is locked into hollow socket  12  and can not be removed until cylindrical sleeve  38   a  is moved to the unlocked position. 
     Camming surface  58  and camming surface  60  are connected with an intermediate camming surface  62  which forces spring  52  to contract as cylindrical sleeve  38   a  is moved between an unlocked position and a locked position. A first stop flange  64 , formed on cylindrical sleeve  38   a  adjacent camming surface  58 , prevents cylindrical sleeve  38   a  from moving beyond the unlocked position when being moved to unlock the reversible tool assembly  18 . First stop flange  64  contacts hook spring  52  while hook  54  is still in hole  42   a  which prevents further movement of cylindrical sleeve  38   a  in a direction away from drive shank  14 . When moving cylindrical sleeve  38   a  to the locked position, a second stop flange  66  on cylindrical sleeve  38   a  adjacent camming surface  60  prevents cylindrical sleeve  38   a  from moving beyond the locked position. The contact between the second stop flange and hook spring  52  stops the movement because hook  54  is held in position within hole  42   a.    
     In operation, drive shank  14  is inserted into the chuck of a powered drill to prepare to drill a pilot hole in a workpiece. If the countersink and drill bit  20  is not exposed, the operator can slide sleeve  38  away from drive shank  14  to unlock the two-ended reversible tool assembly  18  from hollow socket  12 . The reversible tool assembly  18  can then be removed, reversed, and reinserted into socket  12  with countersink and drill bit  20  exposed. Sleeve  38  is then slid toward drive shank  14  to lock reversible tool assembly  18  in hollow socket  12 . The pilot hole and countersink can now be drilled. 
     When the time comes to drive a screw in the pilot hole, sleeve  38  is slid away from drive shank  14  to unlock two-ended reversible tool assembly  18  from socket  12 . Reversible tool assembly  18  is then removed, reversed, and reinserted into socket  12  with screwdriver bit  22  exposed. Sleeve  38  is then slid toward drive shank  14  to again secure reversible tool assembly  18  within socket  12 . The screw may now be driven with screwdriver bit  22 . When drive shank  14  is rotated with the drill, rotational motion is transmitted through the mating polygonal shaped parts to screwdriver bit  22 . 
     With this single tool both the operation of drilling a pilot hole and the operation of driving a screw can be performed. Because a screwdriver bit  22  with polygonal shank can be held in place by magnet  30 , the screwdriver bit can be easily interchanged by just pulling the bit away from the magnet before inserting another screwdriver bit. 
     While the fundamental novel feature of the invention have been shown and described, it should be understood that various substitutions, modifications and variations may be made by those skilled in the art without departing from the spirit or scope of the invention. Accordingly, all such modifications or variations are included in the scope of the invention as defined by the following claims.