Patent Publication Number: US-7913592-B2

Title: Tool holding device

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a tool holding device for a bit and, in particular, the tool holding device is suitable to have an application with a power tool. 
     2. Description of the Related Art 
     U.S. Pat. No. 6,345,560 teaches a clamping chuck including a toolholder in which a bit is adapted to be received. Preferably, the bit has a shank of a standard hexagonal shape and a plurality of recesses disposed thereon. A clamping portion with a hexagonal cross section is connectable to a drive member. An actuating sleeve is connected to the toolholder and is utilized to maneuver a ball to selectively engage in and disengage from one of the recesses in the received bit. Thus, when the ball is engaged in one of the recesses, the received bit is securely retained in the toolholder, and when the ball is disengaged from the recess, the received bit is removable from the toolholder. It is appreciated that the actuating sleeve has a front end with a gradually decreasing outer diameter so if driving a fastener in a hole, a user may insert a portion of the front end of the sleeve which can clear the hole in order that the bit can engage with the fastener. However, if the front end is inserted in the hole and the bit still can&#39;t engage with the fastener, the user then has to use a bit with an elongated shank. Further, the user has to hold the elongated shank to alleviate a wobble of the bit during operation, particularly when the bit is rotated by a power tool rapidly. 
     Also, it is understood that when the received bit is allowed to be removed from the toolholder, the received bit can fall out of the toolholder due to gravity. Therefore, U.S. Pat. No. 6,345,560 teaches a magnet disposed in the toolholder adapted to relieve this problem. However, it is noted that the toolholder and other elements in the toolholder, any of which that are magnetizable, can scatter and, therefore, weaken the magnetic force. Thus, the magnet no longer provides sufficient force to hold the bit from falling out due to gravity. 
     Another chuck device for tool bits is disclosed in U.S. Pat. No. 6,637,755. However, this chuck device does not help the user reduce the demand of using a bit with an elongated shank. 
     In addition, U.S. Pat. No. 6,637,755 teaches a pusher utilized to facilitate removal of the bit received in the chuck device. However, if the user does not hold the bit, the bit will drop out of the chuck device. The user, then, has to pick up the bit which will result an inconvenience. 
     The present invention is, therefore, intended to obviate or at least alleviate the problems encountered in the prior art. 
     SUMMARY OF THE INVENTION 
     According to the present invention, a tool holding device includes a toolholder having a shank and a socket. The shank includes a connecting end at a first end of the toolholder adapted to connect to a power tool. The socket includes a cavity at a second end of the toolholder adapted to receive a bit. The cavity extends in the socket and defines an effective length which is a longitudinal length measured for a boundary wall of the cavity which is adapted to abut a peripheral wall of the bit. The socket also includes an annular wall having a first slot and a second slot cut into a region of the annular wall which corresponds to where the effective length of the cavity is measured. An aperture is defined in the second slot and communicates with the cavity. 
     A hollow sleeve is disposed circumferentially outside the toolholder. The sleeve is axially and rotationally movable in relation to the toolholder and is operable to move between a first position which allows for removal of the bit and a second position which allows the bit to be securely retained in the cavity of the toolholder. The sleeve defines a first section and a second section extending from an end of the first section. A returning member is disposed circumferentially between the toolholder and the second section of the sleeve for returning the sleeve to a neutral position between the first and second positions. Moreover, the portion of the sleeve which does not surround the returning member abuts the toolholder. 
     A clipping member is mounted in the first and second slots and includes an embracing portion disposed about the first slot. A retaining portion is received in the second slot, is inserted in the aperture, and is partially disposed in the cavity. The clipping member is selectively abutted by the first section of the sleeve. When the sleeve is at the first position, the first section of the sleeve does not abut the clipping member, and when the sleeve is at the second position, the first section of the sleeve abuts the clipping member. 
     A hole extends longitudinally in the socket from an end of the cavity and is in communication with the cavity. A through hole extends radially from the annular wall of the socket to the hole and is in communication with the hole. A pusher is disposed in the hole and includes a lateral side having a longitudinally extended recess with two stopping ends at a proximal end and a distal end thereof respectively. A detent is disposed in the through hole and is partially received by the recess. A resilient member is disposed in the hole as to bias the pusher in the hole. The pusher facilitates removal of the bit. 
     In another embodiment of the present invention, the tool holding device includes a magnet disposed in the socket for attracting the bit. 
     Preferably, the socket is made of stainless steel, i.e. austenitic stainless steel, in order that the socket does not scatter the magnetic force of the magnet. 
     Preferably, the pusher is made of copper, so that the pusher does not scatter the magnetic force of the magnet. 
     It is an object of the present invention that the tool holding device effectively reduces demand of using an elongated bit. 
     It is another object of the present invention that the sleeve is axially and rotatably movable in relation to the housing. 
     It is a further object of the present invention that the clipping member prevents the bit from falling out of the tool holding device due to gravity. 
     There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention wilt be described with reference to the accompanying drawings which assist in illustrating the pertinent features thereof, in which: 
         FIG. 1  is a perspective view of a tool holding device in accordance with a first embodiment of the present invention and a bit received in the tool holding device. 
         FIG. 2  is an exploded perspective view of  FIG. 1 . 
         FIG. 3  is a cross-sectional view taken along line  3 - 3  of  FIG. 1 . 
         FIG. 4  is a cross-sectional view taken along line  4 - 4  of  FIG. 3 . 
         FIG. 5  is a side view illustrating the tool holding device in  FIG. 1  connected to a power tool, with the power tool shown in phantom. The tool holding device is inserted in a hole and the bit is adapted to drive a fastener located within the hole, with the fastener shown in phantom. 
         FIG. 6  is a cross-sectional view illustrating a sleeve of the tool holding device in  FIG. 1  operated to allow removal of the bit from the tool holding device. 
         FIG. 7A  is a cross-sectional view of the tool holding device in  FIG. 1 . 
         FIG. 7B  is a partial, enlarged view of  FIG. 7 . 
         FIG. 8  is a perspective view of a tool holding device in accordance with a second embodiment of the present invention and a bit received in the tool holding device. 
         FIG. 9  is an exploded perspective view of  FIG. 8 . 
         FIG. 10  is a cross-sectional view taken along line  10 - 10  of  FIG. 8 . 
         FIG. 11  is a cross-sectional view taken along line  11 - 11  of  FIG. 10 . 
         FIG. 12  is a cross-sectional view illustrating a sleeve of the tool holding device in  FIG. 8  operated to allow removal of the bit from the tool holding device. 
         FIG. 13A  is a cross-sectional view of the tool holding device in  FIG. 8 . 
         FIG. 13B  is a partial enlarged view of  FIG. 13 . 
         FIG. 14  is a cross-sectional view of a tool holding device in accordance with a third embodiment of the present invention and a bit received in the tool holding device. 
         FIG. 15  is a cross-sectional view of a tool holding device in accordance with a fourth embodiment of the present invention and a bit received in the tool holding device. 
         FIG. 16  is a cross-sectional view of a tool holding device in accordance with a fifth embodiment of the present invention and a bit received in the tool holding device. 
         FIG. 17  is a cross-sectional view of a tool holding device in accordance with a sixth embodiment of the present invention and a bit received in the tool holding device. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIGS. 1  though  7  show a tool bit holding device in accordance with a first embodiment of the present invention The tool bit holding device includes a toolholder  10  having a shank  11  and a socket  12  integrally formed therewith. The shank  11  includes a connecting end at a first end of the toolholder  10  adapted to connect to a power tool  90 , as shown in  FIG. 5 . The socket  12  includes a cavity  14  at a second end of the toolholder  10  adapted to receive a bit  93 . The cavity  14  includes six faces encompassing a boundary wall, with each two of the six faces defining an included angle substantially equal to 120° at a corner. The cavity  14  extends in the socket  12  and defines an effective length L which is a longitudinal length measured for the boundary wall of the cavity  14  adapted to abut a peripheral wall of the bit  93 . 
     The socket  12  also includes an annular wall  15  having a first slot  16  and a second slot  161  cut into a region of the annular wall, and an aperture  162  is defined in the second slot  161  and communicates with the cavity  14 . Additionally, the aperture  162  is disposed about one of the corners. 
     A hollow sleeve  20  is disposed circumferentially outside the toolholder  10 . The sleeve  20  is axially and rotationally movable in relation to the toolholder  10  and is operable to move between a first position which allows for removal of the bit  93  and a second position which allows the bit  93  to be securely retained in the cavity  14  of the toolholder  10 . The sleeve  20  includes an inner peripheral edge which circumferentially abuts the annular wall  15  of the socket  12  and an outer peripheral edge. The sleeve  20  defines a first section  21  and a second section  22  extending from an end of the first section  21 . The first section  21  includes a circular cross section and has an uniform internal diameter and an uniform external diameter with respect to a center of the cavity  14 . In this case, the boundary wall of the cavity  14  defines a plurality of corners, i.e. six, and the center of the cavity  14  is a point where the six corners are equally spaced therefrom. The internal diameter is measured from the inner peripheral edge of the sleeve  20  to the center of the cavity  14 . The external diameter is measured from the outer peripheral edge of the sleeve  20  to the center of the cavity  14 . Moreover, the outer peripheral edge of the second section  22  is preferably ridged as to allow a user to hold the sleeve  20  securely during operation thereof. 
     A returning member  40  is disposed circumferentially between the toolholder  10  and the second section  22  of the sleeve  20  for returning the sleeve  20  to a neutral position between the first and second positions. In this embodiment, the returning member  40  is disposed on an engaging portion  17  defined on the annular wall  15  of the socket  12 . The engaging portion  17  includes a first shoulder and a second shoulder  171 ,  172  at a proximal end and a distal end thereof respectively. The second section  22  of the sleeve  20  includes a ridge  24  extending from the inner peripheral edge thereof and toward the engaging portion  17 . The ridge  24  is supported by the first shoulder  171 . Additionally, the returning member  40  includes a first end  41  supported by the ridge  24  and a second end  42  supported by the second shoulder  172 . 
     Optionally, the first end  41  has a cross section greater than that of the second end  42 . 
     Moreover, the portion of the sleeve  20  which does not surround the returning member  40  abuts the toolholder  10 . Referring to  FIGS. 7A and 7B , the first section  21  of the sleeve  20  includes a sleeve region corresponding to where the effective length L of the cavity  14  is measured including a thickness T 21  measured from the inner peripheral edge to the outer peripheral edge thereof. The socket  12  includes a socket region corresponding to where the effective length L of the cavity  14  is measured including a minimum distance T 12  equal to a first length measured from the center of the cavity  14  to the annular wall  15  of the socket  12  subtracted by a second distance measured from the center of the cavity  14  to one corner of the cavity  14 , with thickness T 21  being less than distance T 12 . With this configuration, the tool holding device is adapted to be inserted into a narrow hole to drive a fastener  92 , as shown in  FIG. 5 . It is appreciated that the tool holding device, therefore, can be made with a smaller cross section than any those taught by the prior art. 
     A clipping member  30 , preferably made of metal, is mounted in the first and second slot:  16  and  161  and includes an embracing portion  32  disposed about the first slot  16 . A retaining portion  31  is received in the second slot  161 , is inserted in the aperture  162 , and is partially disposed in the cavity  14 . The clipping member  30  is selectively abutted by the first section  21  of the sleeve  20 . Specifically, when the sleeve  20  is at the first position, the first section  21  of the sleeve  20  does not abut the clipping member  30 . When the sleeve  20  is at the second position, the first section  21  of the sleeve  20  abuts the clipping member  30 . Note that when the sleeve  20  is at the first position, the retaining portion  31  of the clipping member  30  can abut the received bit  93 , particularly one of the cutouts  931  on the bit  93 , in order that the bit  93  is prevented from falling out of the tool holding device due to gravity. Also, when the sleeve  20  is at the second position, the retaining portion  31  of the clipping member  30  is restrained in movement by the first section  21  of the sleeve  20 . Thereby, the tool holding device securely holds the bit  93 . 
       FIG. 4  shows that the annular wall  15  of the socket  12  includes an arcuate area defining the first slot  16  and a flat area defining the second slot  161 . The first slot  16  is contiguous with the second slot  161 . The clipping member  30  includes two embracing portions  32  interconnected by the retaining portion  31 . The two embracing portions  32  are arcuate and are received in the first slot  16 . The retaining portion  31  has a bow-shaped edge which includes an arcuate side and a flat side received in the second slot  161 . 
     In addition, the socket  12  defines a center where the annular wall  15  is equally spaced from the center, and the clipping member  30  defines an arc length having an angle with respect to the center of the socket  12  greater than 180°. 
     A hole  18  extends longitudinally in the socket  12  from an end of the cavity  14  and is in communication with the cavity  14 . A through hole  181  extends radially from the annular wall  15  of the socket  12  to the hole  18  and is in communication with the hole  18 . A pusher  50  is disposed in the hole  18  and includes a lateral side having a longitudinally extended recess  511  with two stopping ends  512  at a proximal end and a distal end thereof respectively. A detent  61  is disposed in the through hole  181  and is partially received by the recess  511 . A resilient member  62  is disposed in the hole  18  as to bias the pusher  50  in the hole. In this embodiment, the pusher  50  facilitates removal of the bit  93 . 
       FIGS. 8  though  13  show a tool bit holding device in accordance with a second embodiment of the present invention. It is noted that like numerals are employed to denote like components of the prior embodiment, however, bearing a letter. This embodiment differentiates from the first embodiment in that a shank  11 A is insertably installed in a tunnel  13  defined in a socket  12 A. The tunnel  13  has a circular cross section and defines a diameter. The shank  11 A defines a length measured from two diagonally opposed corners. The length is marginally smaller than the diameter so that the shank  11 A is securely connected with the socket  12 A. Further, a sleeve  20 A includes a first section  21 A and a second section  22 A releasably mounted to the first section  21 A. Further, the returning member  40  is disposed on the shank  11 A. Specifically, the shank  11 A includes a groove  111 , and the second section  22 A of the sleeve  20 A includes a ridge  24 A extending therefrom toward the shank  11 A. The first end  41  of the returning member  40  is supported by the ridge  24 , while the second end  42  of the returning member  40  is disposed in the groove  111 . Further, a magnet  52  is disposed at an end of the socket  12 A for attracting the bit  93 . 
     Additionally, the socket  12 A includes a cavity  14 A and an annular wall  15 A having an arcuate area defining a first slot  16 A. A second slot  161 A extends radially from the first slot  16 A toward the cavity  14 A, and an aperture  162 A is defined in the second slot  161  and communicates with the cavity  14 A. Further, a clipping member  30 A includes two embracing portions  32 A interconnected by one retaining portion  31 A. The two embracing portions  32 A are arcuate and are received in the first slot  16 A. The retaining portion  31 A has a U-shaped edge and is received in the second slot  161 A. 
     The socket  12 A also includes a center where the annular wall  15 A is equally spaced from the center, and the clipping member  30 A defines an arc length having an angle with respect to the center of the socket  12 A greater than 180°. 
       FIG. 14  shows a tool bit holding device in accordance with a third embodiment of the present invention. It is noted that like numerals are employed to denote like components of the first embodiment, however, bearing a letter. This embodiment differentiates from the first and/or second embodiments in that a socket  12 B includes a cavity  14 B and an annular wall  15 B having an arcuate area defining a first slot  16 B. A second slot  161 B extends radially from the first slot  16 B toward the cavity  14 , and an aperture  162 B is defined in the second slot  161 B and communicates with the cavity  14 B. Further, a clipping member  30 B includes an embracing portion  32 B connected at an end of a retaining portion  31 B. The embracing portion  32 B is arcuate and is received in the first slot  16 B. The retaining portion  31 B has an inverted J-shaped edge received in the second slot  161 B. 
     The socket  12 B also comprises a center where the annular wall  15 B is equally spaced from the center, and the clipping member  30 B defines an arc length having an angle with respect to the center of the socket  12 B greater than 180°. 
       FIG. 15  shows a tool bit holding device in accordance with a fourth embodiment of the present invention. It is noted that like numerals are employed to denote like components of the first embodiment, however, bearing a letter. This embodiment differentiates from the first and/or second embodiments in that a socket  12 C includes a cavity  14 C and an annular wall  15 C having an arcuate area defining a first slot  16 C. Two opposing second slots  161 C extend radially from the first slot toward the cavity  14 C, and two apertures  162 C are defined in the second slots  161 C and communicate with the cavities  14 C respectively. Further, a clipping member  30 C includes two retaining portions  31 C interconnected by an embracing portion  32 C. Each of the two retaining portions  31 C has an inverted J-shaped edge received in the two second slots  161 C respectively. The embracing portion  32 C is arcuate and is disposed about the first slot  16 C. 
     The socket  12 C also includes a center where the annular wall  15 C is equally spaced from the center, and the clipping member  30 C defines an arc length having an angle with respect to the center of the socket  12 C substantially equaling to 180°. 
       FIG. 16  shows a tool bit holding device in accordance with a fifth embodiment of the present invention. It is noted that like numerals are employed to denote like components of the first embodiment, however, bearing a letter. This embodiment differentiates from the first and/or second embodiments in that a socket  12 D includes a cavity  14 D and an annular wall  15 D having an arcuate area defining a first slot  16 D and a flat area defining the second slot  161 D. An aperture  162 D is defined in the second slot  161 D and communicates with the cavity  14 D. The first slot  16 D is contiguous with the second slot  161 D. The clipping member  30 D includes a retaining portion  31 D and an embracing portion  32 D abutting the retaining portion  31 D. The retaining portion  31 D has a bow-shaped edge which includes an arcuate side and a flat side received in the second slot  161 D. The embracing portion  32 D is arcuate and is received in the first slot  16 D. 
     The socket  12 D also include a center where the annular wall  15 D is equally spaced from the center, and the embracing portion  32 D defines an arc length having an angle with respect to the center of the socket  12 D greater than 180°. 
       FIG. 17  shows a tool bit holding device in accordance with a sixth embodiment of the present invention. It is noted that like numerals are employed to denote like components of the first embodiment, however, bearing a letter. This embodiment differentiates from the first and/or second embodiments in that a socket  12 E includes a cavity  14 E and an annular wall  15 E having two opposing arcuate areas and two opposing flat areas defining a first slot  16 E. A second slot  161 E extends radially from the first slot  16 E toward the cavity  14 E, and an aperture  162 E is defined in the second slot  161  and communicates with the cavity  14 E. The clipping member  30 E includes a retaining portion  31 E and an embracing portion  32 E abutting the retaining portion  31 E. The retaining portion  31 E has a ball-shaped edge and is received in the second slot  161 E. The embracing portion  32 E has two first flat sides received in the flat areas of the first slot  16 E respectively, an arcuate side between the two flat sides, and two substantially second flat sides extending from an end of the two first flat sides respectively. 
     The socket  12 E also includes a center where the annular wall  15 E is equally spaced from the center, and the embracing portion  32 E defines an arc length having an angle with respect to the center of the socket  12 E greater than 180°. 
     Moreover, it is advantageous that the socket  12 A,  12 B,  12 C,  12 D,  12 E is made of stainless steel, i.e. austenitic stainless steel, in order that the socket  12 A,  12 B,  12 C,  12 D,  12 E does not scatter the magnetic force of the magnet  52 . 
     Moreover, the pusher  50  is made of copper, so that the pusher  50  does not scatter the magnetic force of the magnet  52 . 
     While the specific embodiments have been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of invention, and the scope of invention is only limited by the scope of the accompanying claims.