Patent Publication Number: US-2010122926-A1

Title: Tool bit exchange system and method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application No. 61/115,366, filed on Nov. 17, 2008 and to U.S. Provisional Patent Application No. 61/166,496, filed on Apr. 3, 2009, the entire contents of both of which are hereby incorporated by reference. 
    
    
     BACKGROUND 
     The present invention relates to a bit exchange system for rapidly exchanging working bits into and out of connection with a tool, such as a power tool for use therewith. Previous attempts at such systems, such as that disclosed in U.S. Pat. No. 7,275,659 to Openiano, have provided for one-hand bit exchange with a power tool, but have required complexities in both the physical components and the movements required of the user during operation, which drawbacks are not shared by the present invention. 
     SUMMARY 
     In one aspect, the invention provides a bit exchange system for use with a tool. The bit exchange system includes a driver bit engageable with the tool and defining an axis. Each of a plurality of adapters has a first end configured to engage the driver bit along the axis and a second end configured to retain a tool bit. Each of a plurality of tool bits is coupled to the second end of one of the plurality of adapters. A holder unit has a plurality of receptacles for receiving the plurality of adapters. Each of the plurality of adapters is insertable into and removable from the respective receptacle with a motion substantially perpendicular to the axis while engaged by the driver bit. 
     In another aspect, the invention provides a bit exchange system for use with a tool. A driver bit is engageable with a tool and defines an axis. An adapter has a first end configured to selectively engage the driver bit along the axis and a second end configured to retain a tool bit. The adapter further includes a sleeve that is axially movable between an open position that allows substantially free insertion and removal of the driver bit into and out of the first end and a closed position in which axial removal of the driver bit from the first end is inhibited. A tool bit is coupled to the second end of the adapter. A holder unit includes a receptacle configured to receive the adapter and a wedge portion adjacent the receptacle. The wedge portion is configured to wedge the sleeve from the closed position to the open position when the adapter is moved into the receptacle. 
     In yet another aspect, the invention provides a method of coupling and decoupling a tool bit with a tool. A driver bit is engaged with the tool. A tool bit is engaged with an adapter. The adapter and the tool bit are stored in a holder unit such that a sleeve of the adapter is held in an open position that allows substantially free insertion and removal of the driver bit into and out of the adapter. The driver bit is inserted into the adapter with a first motion while the adapter is stored in the holder unit. The adapter and the tool bit are removed from the holder unit with a second motion substantially perpendicular to the first motion. The adapter and the tool bit are returned to the holder unit with a third motion, which is substantially a reverse of the second motion. The sleeve of the adapter is wedged open by contact with the holder unit during the third motion to release a locking engagement between the driver bit and the adapter, which allows the driver bit to be freely removed from the adapter. The driver bit is disengaged from the adapter with a fourth motion, which is substantially a reverse of the first motion. 
     Additional features and benefits of the present invention are described and will be apparent from the accompanying drawings and description below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a tool and bit exchange system in one configuration in which a driver bit is engaged with the tool and a plurality of adapters with tool bits are stored in a holder unit. 
         FIG. 2  is a perspective view of the tool and bit exchange system of  FIG. 1  in a configuration in which the driver bit engages one of the adapters. 
         FIG. 3  is a perspective view of the tool and bit exchange system of  FIG. 1  in a configuration in which the engaged adapter is removed from the holder unit for use with the tool. 
         FIG. 3A  is a detail view of an empty receptacle of the holder unit shown in  FIG. 3 . 
         FIG. 4  is a perspective view of the tool and bit exchange system of  FIG. 1  in a configuration in which the engaged adapter is returned to the holder unit after use with the tool. 
         FIG. 5  is a perspective view of the tool and bit exchange system of  FIG. 1  in a configuration in which the driver bit is disengaged from the one adapter and moved toward a second one of the adapters. 
         FIG. 6  is a perspective view of the tool and bit exchange system of  FIG. 1  in a configuration in which the driver bit engages the second one of the adapters. 
         FIG. 7  is a perspective view of the tool and bit exchange system of  FIG. 1  in a configuration in which the second adapter is removed from the holder unit for use with the tool. 
         FIGS. 8A-8D  illustrates various means for supporting the holder unit similar to that of the tool and bit exchange system of  FIGS. 1-7 . 
         FIG. 9  illustrates a modified holder unit for the tool and bit exchange system of  FIGS. 1-7 . 
         FIG. 10  illustrates modified bit adapters for the tool and bit exchange system. 
         FIGS. 11 and 12  illustrate an alternate tool and bit exchange system including a holder unit coupled with a glove-type article. 
         FIG. 13  illustrates a tool and bit exchange system similar to that of  FIGS. 11 and 12 , including a modified holder unit. 
         FIG. 14  is an exploded perspective view of a clamp according to one aspect of the invention. 
         FIG. 15  is a perspective view of the clamp of  FIG. 14  clamped to a planar object. 
         FIG. 16  is a side view of the clamp of  FIG. 14  attached to the object of  FIG. 15 . 
         FIG. 17  is a perspective view of the clamp in a closed position. 
         FIG. 18  is a perspective view of the clamp of  FIG. 14  with a tool and bit exchange system similar to the one of  FIGS. 1-13  attached. 
         FIG. 19  is a perspective view of an upper jaw of the clamp of  FIG. 1 , including a movable attachment interface. 
         FIG. 20  is a perspective view of the upper jaw of the clamp of  FIG. 1 , including the movable attachment interface of  FIG. 19  rotated to a second position. 
         FIG. 21  is a perspective view of the movable attachment interface of  FIG. 19 . 
         FIG. 22  is a top perspective view of the upper jaw of  FIG. 19  with the movable attachment interface removed. 
         FIG. 23  is a perspective view of the upper jaw of the clamp of  FIG. 1 , including a second movable attachment interface. 
         FIG. 24  is a perspective section view of the upper jaw of the clamp of  FIG. 1 , including the second movable attachment interface of  FIG. 23 . 
         FIG. 25  is a perspective view of the upper jaw of the clamp of  FIG. 1 , including the second movable attachment interface of  FIG. 23  rotated to a second position. 
         FIG. 26  is a perspective view of the upper jaw of the clamp of  FIG. 1 , including the second movable attachment interface of  FIG. 23  rotated to a third position. 
         FIG. 27  is a perspective view of an alternate driver bit for use with a tool and bit exchange system. 
     
    
    
     DETAILED DESCRIPTION 
     The invention is described with reference to the drawings in which like elements are referred to by like numerals. The relationship and functioning of the various elements of this invention are better understood by the following description. Each aspect so defined may be combined with any other aspect or aspects unless clearly indicated to the contrary. The embodiments described below are by way of example only, and the invention is not limited to the embodiments illustrated in the drawings. 
       FIGS. 1-7  illustrate a tool and bit exchange system  100  including a tool such as a drill/driver  104  having a chuck  108 . The chuck  108  is closable to releasably engage a driver bit  112  to be rotated by the drill/driver  104 . Various tool bits  116  are provided as part of the system  100 . As shown in the figures, the tool bits  116  may include a screwdriver bit  116 A associated with a first adapter  120 A, a drill bit  1168  associated with a second adapter  120 B, and an additional drill bit  116 C associated with a third adapter  120 C. The driver bit  112  is configured to engage any one of a plurality of bit adapters  120  so that the chuck  108  does not need to be released and re-engaged for every bit change. 
     In some constructions, a mechanical device is provided for coupling and de-coupling the driver bit  112  and any one of the adapters  120 . Such a mechanical device can be a spring-biased ball or other type detent mechanism that provides a positive engagement between one or more balls and a groove. Such a mechanical device can be similar to one of those disclosed in U.S. Pat. No. 6,457,916 and U.S. Pat. No. 6,561,523, both of which are incorporated herein by reference. As with the devices of the two above-mentioned patents, an exterior sleeve  121  can be provided to change the mechanical device from a locked or closed state to an unlocked or open state. In the locked or closed state, the driver bit  112  and the adapter  120  are inhibited or prevented from being pulled apart, while the driver bit  112  is freely insertable into and removable from the adapter  120  when in the unlocked or open state. Alternately, other means can be provided to selectively inhibit and allow separation of the driver bit  112  from the adapters  120 . For example, the device need not be a detent mechanism and can instead be a one-way linear bearing or other type mechanism that inhibits axial decoupling of the driver bit  112  and an engaged adapter  120  when the sleeve  121  is in the locked or closed position. In such a construction, no groove is required in the shank of the driver bit  112 , since the resistance to disengagement is provided by balls or rollers that bind to prevent axial removal of the driver bit  112  until the sleeve  121  is moved to the unlocked or open position. 
     Each one of the adapters  120  has a first end configured to engage the driver bit  112  for rotational driving engagement. In particular, the adapters  120  of the illustrated construction include openings at the first ends that have a shape that corresponds to the shape of the driver bit  112  (e.g., hex, double-hex, Torx, etc.) and is capable of transmitting torque from the driver bit  112  to the adapter  120 . A second end of each adapter  120  opposite the first end is configured to receive a tool bit  116  and enable torque to be transmitted from the adapter  120  to the tool bit  116 . The first adapter  120 A is provided with a hex-shaped receptacle to receive a drive portion of the screwdriver bit  116 A. The second and third adapters  120 B,  120 C can be provided with round openings sized to receive the respective drill bits  116 B,  116 C. Additional adapters  120  can be provided as part of the system  100  to be used with one or more additional tool bits  116 . 
     Each adapter  120  can include a locking mechanism  140 , such as a set screw, to prevent the respective bit  116  from becoming inadvertently separated from the adapter  120  and/or to prevent relative rotation between the bit  116  and the adapter  120 . The locking mechanism  140  can include, among other things, a magnetic device, a ball detent arrangement, or a miniature multi-jaw chuck as alternatives to set screws. Although not shown, the third adapter  120 C also includes a locking mechanism  140  to engage the drill bit  116 C. The tool bits  116  can be substantially conventional tool bits  116  so that the benefits of the invention may be realized with a user&#39;s existing tool bits  116 . Furthermore, at least the first adapter  120 A is configured to receive any one of a plurality of different tool bits that have a common hex-shaped drive portion. 
     All of the adapters  120  of the system  100  are able to be stored in a holder unit  144  for easy access. The holder unit  144  includes a receptacle  148  for each adapter  120 . As shown in the figures, each adapter  120  may include a groove or relief  152  at a central portion that is sized to engage the edge of one of the receptacles  148  so that the adapters  120  are movable into and out of the storage position on the holder unit  144  along the directions of double arrow A ( FIG. 1 ), and the adapters  120  are otherwise securely supported within the receptacles  148 . 
     Although other shapes are optional, the illustrated holder unit  144  is generally L-shaped, having a first portion  144 A with the receptacles  148  and a second portion  144 B extending at a substantially 90 degree angle from the first portion  144 A. The adapters  120  can be retained with the holder unit  144  by a magnetic retention mechanism to inhibit incidental release of the adapters  120  from the respective receptacles  148 . The attraction of the adapters  120  to one or more magnets on the holder unit  144  is strong enough to prevent the adapter  120  from falling out of the receptacle  148 , but weak enough to easily be overcome by an average user when a user makes an effort to remove the adapter  120  from the receptacle  148 . Alternatively, mechanical retention mechanisms can be provided to retain the adapters  120  on the holder unit  144 . Such mechanical retention mechanisms may include resilient clips, hook-and-loop strips, etc., none of which require a user to grasp or otherwise engage the holder unit  144  in order to release the adapters  120  from the holder unit  144 . 
     As shown in  FIG. 8 , the holder unit  144  may be supported in a variety of convenient locations for storage and/or access during a work task. By way of example,  FIG. 8  illustrates the holder unit  144  supported on a bucket tool organizer  160 , a step ladder  162 , a user&#39;s belt  164 , and a user&#39;s wrist  166 . The holder unit  144  can be provided with one or more clips (not shown) that enable easy attachment to a variety of support structures (including those shown in  FIG. 8 ). As configured to be supported on a user&#39;s wrist  166 , the holder unit  144  can be provided with one or more wrist straps  170  that secure the holder unit  144  to the user&#39;s wrist  166 . In some constructions, the wrist straps  170  may be releasably secured to the holder unit  144  by the same clips that enable the holder unit to be supported on a belt  164  or other structure. In other constructions, the wrist straps  170  are coupled to the holder unit  144  by alternate fasteners or made integral (i.e., non-releasably fixed) with the holder unit  144 . The wrist straps  170  can wrap around the user&#39;s wrist  166  and be secured with hook-and-loop strips, clasps, buckles, etc. 
     The illustrated tool and bit system  100  enables a user to complete a task requiring multiple tool bits  116  quicker and more easily than previously possible. First, the user loads the required tool bits  116  into the adapters  120  by inserting the tool bits  116  into the adapters  120  and locking them in place, with the locking mechanisms  140  if necessary. Once the adapters  120  are loaded with the tool bits  116 , the adapters  120  are loaded into the holder unit  144 . Although the holder unit  144  is illustrated with three receptacles  148  for three adapters  120 , the system  100  can include more adapters  120  for additional tool bits  116 , and the holder unit  144  may be provided with one, two, or more than three receptacles  148 . 
     The user loads the driver bit  112  into the chuck  108  of the drill/driver  104  so that the driver bit  112  is aligned with the tool&#39;s axis TA and is configured to be rotated about the axis TA with the chuck  108  when the drill/driver  104  is energized. The user secures the holder unit  144  at a convenient location, including for example on the body of the user, for access during the work task. When the holder unit  144  is provided with the wrist straps  170 , the holder unit  144  is supported on the wrist  166  of the user opposite the hand used to operate the drill/driver  104 . When the holder unit  144  is coupled to the user&#39;s belt  164 , the user may choose to locate the holder unit  144  on the same side of the body as the hand used to operate the drill/driver  104 . 
     As shown in  FIGS. 1 and 2 , the user aligns the tool axis TA with an axis AB of the desired adapter  120 B and moves the drill/driver  104  with a first motion M 1  ( FIG. 2 , substantially parallel to the axis AB) toward the holder unit  144 . The axis AB of the adapter  120 B is shared with the tool bit  116 B associated therewith. With the first motion M 1  of the drill/driver  104 , the driver bit  112  is inserted into the adapter  120 B that is loaded with the first desired tool bit  116 B. The holder unit  144  holds the adapter  120 B stationary while the driver bit  112  is coupled to the adapter  120 B. As shown in  FIG. 3 , the user slides the adapter  120 B out of the receptacle  148  with a second motion M 2  ( FIG. 3 , substantially perpendicular to the tool axis TA and the adapter axis AB) to disengage the adapter  120 B from the holder unit  144 . As long as the holder unit  144  is properly secured, the user is able to load the adapter  120 B onto the driver bit  112  and release the adapter  120 B from the holder unit  144  with a single hand, while the other hand is free and can be used to hold another tool, a fastener, or the workpiece, among other things. Once the first selected adapter  120 B is released from the holder unit  144 , the user uses the first selected tool bit  116 B by operating the drill/driver  104 . 
     When the task of the first selected tool bit  116 B is complete and the user requires another of the tool bits  116 A,  116 C, the user returns the first selected adapter  120 B (still engaged with the driver bit  112 ) to the holder unit  144  as shown in  FIG. 4 . The user slides the adapter  120 B with a third motion M 3  ( FIG. 4 , substantially a reverse of the second motion M 2 ) into a/the vacant receptacle  148  such that the groove  152  in the adapter  120 B is engaged by the holder unit  144 . When the adapter  120 B is fully seated into the receptacle  148 , the user pulls the driver bit  112  (still in engagement with the chuck  108 ) out of engagement with the adapter  120 B by a fourth motion M 4  ( FIG. 5 , substantially a reverse of the first motion M 1 ). The adapter  120 B is held fixed with the holder unit  144  via the groove  152  as the user makes the fourth motion M 4  to retract the driver bit  112 . 
     As shown in  FIGS. 5 and 6 , the user moves the driver bit  112  over to align the tool axis TA with the axis AA of the adapter  120 A containing the next desired tool bit  116 A. The user then inserts the driver bit  112  into the adapter  120 A with a fifth motion M 5  ( FIG. 6 , substantially parallel to the tool axis TA and the axis AA of the adapter  120 A). The adapter  120 A is removed from the holder unit  144  with a sixth motion M 6  ( FIG. 7 , substantially perpendicular to the tool axis TA and the adapter axis AA), and the user uses the second selected tool bit  116 A for the next task. 
     From the time that the driver bit  112  is loaded into the chuck  108  and the holder unit  144  is loaded with adapters  120  loaded with the required tool bits  116 , the user only requires the use of a single hand to arm the drill/driver  104  with the first tool bit  116 B, remove the tool bit  116 B from its stored position, operate the drill/driver  104 , return the tool bit  1168  to its stored position, and exchange the first tool bit  1168  for the second tool bit  116 A. The particular task of the user may require exchanging between more than two tool bits  116  and/or exchanging back and forth between the same tool bits  116  repeatedly. Thus, a great deal of time and effort is saved by the tool and bit exchange system  100  when multiple tool bits  116  must be exchanged for sequential use with the drill/driver  104 . Although the figures illustrate the tool as being a drill/driver  104 , the invention can be adapted for use with other power tools. Likewise, the invention can be useful for manual tools as well. 
     In some constructions, a positive engagement (e.g., by a ball and groove detent or other mechanism) between the driver bit  112  and the first end of one of the adapters  120  can be established or broken while the adapter is stored or held fixed in the holder unit  144 . In a construction where the adapters  120  are equipped with axially movable sleeves  121  that must be moved to cause the establishment or breaking of a positive engagement between the driver bit  112  and the adapter  120 , a feature of the holder unit  144  may be provided to automatically move the sleeve  121  when the adapter  120  is moved into and out of engagement with the holder unit  144 . As shown in  FIG. 3A , the holder unit  144  can be provided with a wedge portion  175  adjacent the receptacle  148 . The wedge portion  175  is configured to wedge the sleeve  121  of the adapter  120 B from the locked or closed position (to which it may be biased) to the unlocked or open position as the adapter  120 B is inserted into the receptacle  148  (i.e., moved with the third motion M 3  perpendicular to the axes TA and AB). In the illustrated construction, the wedge portion  175  constitutes a change in thickness in the first portion  144 A of the holder unit  144 . Wedge portions like that shown in  FIG. 3A  can be provided on both sides of each receptacle  148  in the holder unit  144 . Once wedged to the unlocked or open position by insertion of the adapters  120  into the receptacles  148 , the holder unit  144  retains the sleeve  121  of each of the adapters  120  in the unlocked or open position until eventually removed for use with the drill/driver  104 . 
       FIG. 9  illustrates a modified holder unit  244  including receptacles  248  having flared openings  250  to make it easier for the user to insert the adapters  120  into the receptacles  248 . The flared openings  250  make it easier for the user to exchange between tool bits  116  “by feel” without looking towards the holder unit  244 . Furthermore, the modified holder unit  244  includes a cap  254  having funnels  258  above each receptacle  248  to help guide the driver bit  112  into the corresponding opening in the desired adapter  120 . The cap  254  may include labels (not shown) including letters, words, and/or numbers that are indicative of the tool bit  116  contained in each adapter  120  to help the user identify the funnel  258  into which the driver bit  112  must be inserted to arm the drill/driver  104  with the desired tool bit  116 . 
       FIG. 10  illustrates a set of modified adapters  320  in a holder unit  344  similar to the holder unit  144  of  FIGS. 1-8 . The adapters  320  are provided with first ends  322  configured to receive a driver bit (similar to the driver bit  112 , for example) and second ends  324  configured to receive drive portions of the respective tool bits  316 . The tool bits  316  are provided with non-round drive portions (e.g., hex-shaped shanks) that engage non-round openings in the second ends  324 . A mechanical device, which can be similar to those disclosed in U.S. Pat. No. 6,457,916 and U.S. Pat. No. 6,561,523 in some constructions, can be provided at the second ends  324  of the adapters  320  in addition to the first ends  322 . Accordingly, both ends  322 ,  324  can be provided with movable sleeves  321  that selectively allow the release of the driver bit and tool bits  316 , respectively. Thus, loading of the tool bits  316  into the adapters  320  is not only simplified, but the adapters  320  are substantially “universal” to accept all or at least a large number of tool bits  316  (which can include more than those illustrated). Although each tool bit  316  may be provided with a circumferential groove to receive a ball of a detent mechanism as shown in the two above-mentioned patents, a groove need not be provided in the shank if the mechanical device at each end the adapter  120  is configured as a one-way linear bearing with balls or rollers that bind and prevent axial removal of the driver bit or tool bits  316  until the corresponding sleeve  321  is moved to the unlocked or open position. 
       FIGS. 11 and 12  illustrate an alternate tool and bit exchange system  400  including a drill/driver  404  with a chuck  408 , a driver bit  412 , a holder unit  444 , a plurality of bit adapters  420  storable in the holder unit  444 , and a plurality of tool bits  416  associated with the adapters  420 . The tool and bit exchange system  400  is similar to the system  100  of  FIGS. 1-7 , except as noted below. Similar reference numbers are used where appropriate, with a different leading digit. A tool and bit exchange system of the present invention may include combinations of features shown in separate physical constructions. 
     In the illustrated construction the plurality of tool bits  416  includes a drill bit  416 A, a countersinking bit  416 B, and a screwdriver bit  416 C. The illustrated combination of tool bits  416  can be used to drill a hole in a workpiece, countersink the hole, and drive a fastener  460  into the countersunk hole. As with the system  100  of  FIGS. 1-7 , the system  400  of  FIGS. 11 and 12  allows the user to repeatedly exchange the tool bits  416  with which the drill/driver  404  is armed with a single hand and without operating the chuck  408 , or grasping the adapters  420  or the tool bits  416 . 
     The holder unit  444  of  FIGS. 11 and 12  is coupled with a glove-type article  464  configured to be worn on the hand/wrist area  466  of the user opposite the hand  468  that is used to operate the drill/driver  404 . The article  464  includes a body portion  470  to which the holder unit  444  is attached. The article  464  further includes a thumb hole  474  and a pair of straps  478  with clasps  480 . The straps  478  are elastic and/or length-adjustable. The thumb hole  474  offers the user great control of the holder device  444  during exchange of the adapters  420 . 
     As described, but not illustrated, with respect to the system  100  of  FIGS. 1-7 , the holder unit  444  includes magnets  484  configured to retain the adapters  420  until needed by the user. The magnets  484 , which are disc-shaped (but can be otherwise shaped), are coupled to the second portion  444 B of the holder unit  444 . 
       FIG. 13  illustrates a tool and bit exchange system  500  similar to those of  FIGS. 1-7  and  FIGS. 11-12 , including a modified holder unit  544 . Similar reference numbers are used where appropriate, with a different leading digit. The holder unit  544  includes a guard portion  546  that extends from the second portion  544 B in the direction of extension of the stored tool bits  516 . The guard portion  546  can extend about the same length as the longest tool bit  516 A. The guard portion  546  can be molded from plastic, although other materials and manufacturing methods are optional. The guard portion  546  substantially covers the tool bits  516  from at least one side to prevent incidental contact between the tool bits  516  and nearby objects and/or people, including the user. 
       FIG. 14  illustrates a clamp  600  that can be used in conjunction with or separate from an accessory, such as the holder unit  144  of the bit exchange system  100  of  FIGS. 1-7 , among others. The clamp  600  includes an upper jaw  605  and a lower jaw  610  that pivotally attach to one another to define a handle end  615  and a jaw end  620  that are movable between a closed position and an open position. A biasing member  625  is positioned to bias the jaw end  620  toward the closed position. 
     The upper jaw  605  includes an attachment region  630 , a handle region  635 , and a jaw region  640 . The handle region  635  includes a curved outer surface  645  shaped to fit within the palm of a user&#39;s hand. In preferred constructions, the handle region  635  is substantially hollow and is sized to receive a portion of the biasing member  625 . Of course other constructions could employ a solid handle region or partially hollow region if desired. 
     The attachment region  630  is positioned between the handle region  635  and the jaw region  640 . The attachment region  630  includes two ears  650  that include an aperture  655  that passes through both ears  650  along a pivot axis  660 . 
     The jaw region  640  includes an outer surface  665  that is substantially planar and that is adapted to receive an accessory, such as the holder unit  144  of the bit exchange system  100  of  FIGS. 1-7 , for example. Two side members  670  cooperate with the outer surface  665  to define a dovetail fit  675  for receiving the accessory. Of course other attachment arrangements could be employed if desired. 
     The jaw region  640  includes a pair of curved surfaces  680  opposite the outer surface  665  and adjacent the attachment region  630 . The curved surfaces  680  include a plurality of serrations or teeth  685  that cooperate to more firmly secure the clamp  600  to a cylindrical object as will be discussed. In the illustrated construction, two curved surfaces  680  support the teeth  685 . However, other constructions could employ a single surface  680  or three or more surfaces  680  if desired. 
     The jaw region  640  also includes a pad attachment portion  690  opposite the outer surface  665  and adjacent the curved surfaces  680 . The pad attachment portion  690  includes two attachment ears  695  that extend substantially normal to the outer surface  665  and define a space  700  therebetween. An aperture  705  passes through both ears  695  and defines a pad pivot axis  710  that is substantially parallel to the pivot axis  660 . 
     The lower jaw  610  is substantially the same as the upper jaw  605 . However, the attachment region  630  of the lower jaw  610  includes two ears  715  that are offset with respect to the ears  650  of the upper jaw  605 . In the illustrated construction, the lower ears  715  are offset inward, toward a bisecting plane of the jaw  610 . The offset allows the ears  650  of the upper jaw  605  to pass outside of the ears  715  of the lower jaw  610  to align the pivot axes  710  (and the apertures  705 ) of the upper jaw  605  and lower jaw  610 . Once aligned, a pivot pin  720  is inserted through the apertures  705  in the four ears  650 ,  715  and the upper jaw  605  and lower jaw  610  are pivotally attached to one another. 
     Pivot pads  725  are pivotally attached to each of the upper jaw  605  and the lower jaw  610  to facilitate clamping to planar objects. Each pad  725  includes a substantially rectangular portion  730  and an attachment boss  735  extending from the rectangular portion  730 . The attachment boss  735  includes an aperture  740  that passes through the boss  735 . The boss  735  is sized to fit within the space  700  between the attachment ears  695  of the upper jaw  605  and lower jaw  610 . When positioned within the space  700 , the boss aperture  740  aligns with the apertures  705  in the ears  695  to allow for the insertion of a pivot pin  745 . Once positioned, the pin  745  provides a pivot axis  750  for the pad  725  which allows the pad  725  to pivot with respect to the remainder of the clamp  600 . It should be noted that while the illustrated pads  725  include a rectangular portion  730 , other constructions may employ other shapes as desired. 
     In the illustrated construction, each pad  725  includes an engagement surface  755  opposite the boss  735 . The engagement surface can be a planar surface, or could be a roughened surface designed to increase the friction between the clamp  600  and the surface to which it is being attached. In still other constructions, a friction enhancing member is attached to the engagement surface  755 . For example, in one construction a rubber pad is bonded to the engagement surface  755  to improve the clamping ability of the clamp  600 . 
     The biasing member  625  includes a torsional spring that is positioned between the upper jaw  605  and the lower jaw  610 . The torsional spring includes a first arm  760 , a second arm  765 , and a coil portion  770 . The coil portion  770  is positioned adjacent the attachment region  630  of the jaws  605 ,  610  and is held in a fixed position with respect to the jaws  605 ,  610 . The first arm extends along the upper jaw  605  and is positioned within the hollow handle region  635 . The second arm  765  is similarly positioned within the hollow handle region  625  of the lower jaw  610 . 
     In operation, the user grasps the handle region  635  of the two jaws  605 ,  610  when the clamp  600  is in the position illustrated in  FIG. 17 . The user squeezes the two handle regions  635  toward one anther to open the jaw regions  640  of the clamp  600  and to overcome the biasing force of the biasing member  625 . Once opened, the user positioned the jaw regions  640  around the object to be clamped and releases the two handle regions  635 . The biasing member  625  moves the jaw regions  640  toward a closed position until the pads  725  contact the object being clamped. The pads  725  are free to pivot slightly to accommodate clamping to objects without parallel surfaces. Once clamped, the biasing member  625  provides the necessary clamping force to hold the clamp  600  in position. 
     A similar process is followed to clamp to a cylindrical object such as a pipe. However, rather than the pads  725  contacting the pipe, the teeth  685  of the curved surfaces  680  contact the pipe and provide sufficient grip to inhibit unwanted movement. 
     Turning to  FIG. 18 , the clamp  600  of  FIG. 1  is shown with a holder unit  744  of a bit exchange system that is similar to the holder unit  144  of the bit exchange system  100  illustrated in  FIGS. 1-7 . The illustrated holder unit  744  includes three receptacles  748  that support three separate adapters  120 A-C that are loaded with three tool bits  716  that may be needed for a particular operation. In addition, two smaller receptacles  775  are positioned outside of the receptacles  748  and are configured to hold other objects such as screws  780 . 
     The holder unit  744  of  FIG. 18  includes a dovetail fit portion  785  that engages the dovetail fit  675  of the clamp  600  to hold the holder unit  744  in place relative to the clamp  600 . In other constructions, other attachment means may be employed. For example, fasteners, hook and loop type fasteners (VELCRO), and the like could be employed in place of, or in conjunction with the dovetail  675 ,  785 . In still other constructions, magnets are used to magnetically connect the holder unit  744  to the clamp  600 . 
       FIGS. 19-22  illustrate an additional construction in which an upper jaw  605   a  of a clamp  600   a  includes a substantially planar top surface  790  that receives a movable attachment interface  800  that is arranged to support a holder unit, such as the holder unit  744 , of a bit exchange system. As illustrated in  FIGS. 19 and 20 , the upper jaw  605   a  includes a second substantially planar surface  805  opposite the top surface  790 , such that the wall thickness from the top surface  790  to the bottom surface  805  is substantially uniform. 
       FIGS. 19-22  illustrate one construction of the upper jaw  605   a  for the clamp  600   a  that includes a first movable attachment interface  800   a.  With reference to  FIG. 22 , the upper jaw  605   a  (and the lower jaw if desired) includes several apertures  810  formed in the planar top surface  790  to receive the movable attachment interface  800   a.  Each aperture  810  includes a large diameter portion  815  and a smaller diameter slot portion  820  extending from one side of the large diameter portion  815 . As illustrated in  FIGS. 19 and 20 , the apertures  810  pass through the upper jaw  605   a  and through the top planar surface  790  and the second planar surface  805 . 
     In the illustrated construction, the apertures  810  are arranged in pairs. For each pair, the slots  820  extend from the large diameter portion  815  in the same direction. The illustrated construction includes two pairs arranged at about 90 degrees with respect to one another, with other constructions being arranged at different angles and/or including additional, or fewer, pairs of apertures  810  if desired. 
       FIG. 21  illustrates the first movable attachment interface  800   a  which includes a substantially planar bottom surface  825 , and a dovetail fit  830  opposite the bottom surface  825 . The dovetail fit  830  is similar to the dovetail fit illustrated in  FIGS. 1-18  and is sized to receive a mating dovetail fit on the holder unit  744 . Of course other constructions could employ different attachment techniques and fits to attach the holder unit  744  to the first attachment interface  800   a.  Several of these different approaches were discussed with regard to  FIGS. 1-18  and are equally applicable to the constructions of  FIGS. 19-26 . 
     Two mushroom studs  835  extend outward from the bottom planar surface  825 . Each mushroom stud  835  includes a cylindrical neck portion  840  and a cylindrical head portion  845 . The head portion  845  has a larger diameter than the neck portion  840 . 
     As illustrated in  FIGS. 19 and 20 , the mushroom studs  835  are sized such that the large diameter head  845  can pass through the large diameter portion  815  of the apertures  810  but cannot pass through the smaller diameter slot portions  820  of the apertures  810 . The neck  840  is sized to fit through both the large diameter portion  815  and the smaller diameter slot  820 . Thus, the heads  845  are inserted into the desired apertures  810  and then the first attachment member  800   a  is slid along the slot portions  820  to lock the movable member  800   a  in place. As illustrated in  FIG. 19 , the first movable attachment member  800   a  can be positioned in two orientations in which a long axis of the attachment member  800   a  is substantially parallel with the long axis of the clamp  600   a.  Alternatively, the first movable attachment member  800   a  can be positioned in two orientations as illustrated in  FIG. 20 . In these positions, the long axis of the movable member  800   a  is approximately normal to the long axis of the clamp  600   a.  Of course other arrangements are possible when other aperture pairs are provided. 
     The arrangement of  FIGS. 19-22  allows a user to position the movable attachment interface  800   a,  and therefore the holder unit  744  at one of four orientations to improve access to the accessories. A first orientation is illustrated in  FIG. 19 . In this orientation, the movable attachment interface  800   a  is arranged such that its long axis is substantially parallel to the long axis of the clamp  600   a  and the open end of the dovetail fit  830  is near the jaw end  620  of the clamp  600   a.  A second orientation uses the same apertures but positions the open end of the dovetail fit  830  near the handle end  615  of the clamp  600   a.  A third orientation is illustrated in  FIG. 20 . In this orientation, the attachment interface  800   a  is rotated 90 degrees with respect to its position in  FIG. 19 . In a fourth orientation, the attachment interface  800   a  is rotated 180 degrees from the position illustrated in  FIG. 20 . In the fourth orientation, the attachment interface  800   a  engages the same apertures as those used in the third orientation. 
       FIGS. 23-26  illustrate another construction of an upper jaw  605   b  for a clamp  600   b  which includes a second movable attachment interface  800   b.  As with the construction of  FIGS. 19-22 , a top surface  850  of the upper jaw  605   b  is substantially planar. A central aperture  855  is formed in the upper jaw  605   b  and passes through the upper jaw  605   b.  A counterbore  860  is formed from the top surface  850  such that the aperture has a larger diameter near the top surface  850 . Two side apertures  865  extend part way through the upper jaw  605   b  from the top surface  850 . In the illustrated construction, the apertures  855  are positioned on either side of the central aperture  855  along a line that is substantially normal to the long axis of the clamp  605   b.  However, other positions for these apertures  865  could be employed if desired. 
     A ball detent mechanism  870  is positioned within each of the side apertures  865  as illustrated in  FIG. 24 . Each ball detent mechanism  870  includes a spring  875  having a first end in contact with the bottom of the side aperture  865  and a second end that supports a ball  880  that is sized to fit within the side aperture  865 . The spring  875  is sized to support the ball  880  above the top surface  850  when no other force is applied to the ball  880 . A locking member may be employed to hold the ball detent mechanism  870  within the aperture  865  if desired. However, preferred constructions do not employ a locking member. Rather, the second movable attachment interface  800   b  functions as a locking member as will be discussed below. 
     The second movable attachment interface  800   b  is similar to the first movable attachment interface  800   a  in that it includes a substantially planar bottom surface  885  and a dovetail fit  870  opposite the planar bottom surface  885 . As noted, other attachment methods could be employed in place of the dovetail fit  890 . In those constructions, the dovetail fit  890  would be omitted and replaced with the proper configuration for the particular attachment method being employed. 
     A post  895  extends downward from the planar bottom surface  885  and facilitates attachment of the second attachment interface  800   b  to the upper jaw  605   b.  The post  895  is a substantially cylindrical member sized to fit within the counterbore portion  860  of the central aperture  855 . A center bore  900  is formed in the post  895  and is sized to receive an attachment fastener  905 . The fastener  905  passes through the upper jaw  605   b  from the bottom surface  885  and engages the second movable attachment interface  800   b  in a way that allows the attachment interface  800   b  to rotate about an axis  910  centered on the post  895  but that inhibits axial movement along that axis  910 . In one construction, the fastener  905  threadably engages the post  895 . In other constructions, an adhesive attaches the fastener  905  to the post  895 . In still other constructions, a combination of threads and adhesive are employed. As one of ordinary skill in the art will realize, many alternative attachment systems could be employed if desired. 
     A plurality of slots  915  are formed in the bottom planar surface  885  of the attachment interface  800   b  and extend radially outward from the post  895 . The slots  915  have a width that is about equal to the diameter of the balls  880  and a depth of about half the diameter of the balls  880 . In preferred constructions, the slots  915  have a semi-circular cross-section that facilitates receipt of the balls  880 . In the illustrated construction, the slots  915  are arranged in four pairs which will allow for eight different orientations of the attachment interface  800   b.  Of course, other constructions could employ more pairs of slots  915  or fewer pairs of slots  915  as desired. In constructions that employ more pairs of slots  915 , the size of the balls  880  would likely need to be reduced from those shown to provide the necessary space. 
     It should be noted that while the illustrated construction includes a pair of ball detents  870  and pairs of slots  915  to receive the balls  880 , other constructions could employ a single ball detent mechanism  870  that is received in a single slot  915  or even a single semi-spherical aperture if desired. Furthermore, still other constructions could employ three or more ball detent mechanisms  870  if desired. 
       FIGS. 23 ,  25 , and  26  illustrate the second attachment interface  800   b  positioned in three of eight possible orientations. When positioned in one of the possible orientations, the springs  875  bias the balls  880  upward and into the slots  915 . With the balls  880  in the slots  915 , unwanted rotation of the attachment interface  800   b  is inhibited. To rotate the interface  800   b  to a different position, the user applies a torque to the interface  800   b.  As the interface  800   b  rotates, the balls  880  are forced downward against the spring force until they disengage with the slots  915 . The user than rotates the interface  800   b  until the balls  880  engage the next slots  915 . The springs  875  bias the balls  880  into the slots  915  to again inhibit unwanted rotation. The second attachment interface  800   b  also inhibits removal of the balls  880  as its axial position along the axis  910  is substantially fixed when the second attachment interface  800   b  is coupled to the fastener  905 . 
       FIG. 23  illustrates one orientation in which the long axis of the attachment interface  800   b  is substantially parallel to the long axis of the clamp  600   b  and the open end of the dovetail fit  870  is adjacent the jaw end  620  of the clamp  600   b.  A second orientation employs the same slots  915  but is rotated 180 degrees such that the open end of the dovetail fit  890  is positioned toward the handle end  615  of the clamp  600   b.    
       FIG. 25  illustrates a third orientation in which the long axis of the attachment interface  800   b  is substantially normal to the long axis of the clamp  600   b.  A fourth orientation uses the same slots  915  but is rotated 180 degrees from the position illustrated in  FIG. 25 . 
       FIG. 26  illustrates a fifth orientation in which the attachment interface  800   b  is rotated 45 degrees counterclockwise with respect to the position illustrated in  FIG. 25 . A sixth orientation employs the same slots  915  with the attachment interface  800   b  rotated 180 degrees from that illustrated in  FIG. 26 . While not illustrated, a seventh orientation exists in which the attachment interface  800   b  is rotated 45 degrees clockwise with respect to the position illustrated in  FIG. 25 . An eighth orientation employs the same slots  915  with the attachment interface  800   b  rotated 180 degrees from the clockwise position of the seventh orientation. 
     Thus, the construction of  FIGS. 19-22  is able to orient the holder unit  744  of the bit exchange system in one of four different orientations without moving the clamp  600   a.  Similarly, the construction of  FIGS. 23-26  is able to orient the holder unit  744  in one of eight different orientations without moving the clamp  600   b.    
     In use, the clamp  600  of  FIG. 18  is attached to an article near a work site such that the user is able to easily access the various tool bits and/or other contents held in the holder unit  744 . The user does not have to search for or even grasp the bits or the holder unit  744  between operations, making the exchange of bits a simple, one-handed operation (i.e., the one hand that grasps the tool to which the bits are exchanged). If the constructions of  FIGS. 19-26  are being employed, the user can first position the clamp  600   a,    600   b  and then orient the holder unit  744  in the most convenient of the available positions. 
       FIG. 27  illustrates driver bit  812  or arbor for use with an impact drill or hammer drill that operates not only to rotate a tool bit but also to “hammer” or repeatedly axially impact the workpiece. Thus, the driver bit  812  is provided with a hex-shaped shank  814  that includes a circumferential groove  816 . The shank  814  is received into the chuck of the impact drill and the groove  816  is engaged by a detent so that the hammering force is efficiently conveyed from the chuck of the impact drill to the driver bit  812 . The opposite end of the driver bit  812  is selectively engageable with any one of a plurality of quick-release adapters to which each of a plurality of tool bits is coupled, as described above, so that rapid, hands-free exchange of tool bits may be accomplished. 
     The foregoing detailed description has described only a few of the many forms that this invention can take. For this reason, this detailed description is intended by way of illustration, and not by way of limitation.