Abstract: A tool (10) including a drive shaft (36) having an axis of rotation, and a plurality of bit holders (28,30) interchangeable with one another at a position of use. The bit holders (28,30) being mounted on a turret (26) which is rotatable around an axis (k) set at an angle to the axis of rotation of the drive shaft (36). The drive shaft (36) being in drive connection with a respective bit holder (28,30) at the position of use, wherein the tool (10) includes means (20x) for engaging a clutch (46) which activates a drive train (44) to establish a drive connection between the drive shaft (36) and the turret (26) so that subsequent operation of the drive shaft (36) rotates the turret (26) to interchange the positions of the bit holders (28,30) at the position of use, and wherein after the turret (26) has been rotated the clutch (46) is disengaged to deactivate the drive train (44) to prevent any further rotation of the turret (26).

Abstract: A tool including a drive shaft having an axis of rotation and a plurality of bit holders interchangeable with one another at a position of use. The bit holders are mounted at arcuately-spaced positions on a turret rotatable around an axis that is set at an angle to the axis of rotation of the drive shaft. The drive shaft is reciprocal between first and second axially-spaced locations at which, respectively, the drive shaft is engaged and disengaged from the bit holder at the position of use. The positioning of the drive shaft at the second location establishes a drive connection between the drive shaft and the turret so that subsequent operation of the drive shaft rotates the turret to interchange the positions of the bit holders at the position of use. The drive shaft is adapted to return to the first location and restore the drive connection with a new bit holder at the position of use after the turret has been rotated.

Abstract: A pistol grip drill (1) has two control triggers (3 and 9) on its hand grip (4). One trigger (3) controls power to a motor in a casing (2) of the drill and the other trigger (9) initiates a sequence which interchanges the positions of two chucks (20, 21). The chucks (20, 21) are mounted on a forward extension (8) of the casing (2). The extension (8) has two degrees of freedom. It is firstly capable of rotating through ninety degrees about the axis of a pivot (14) to bring the unused chuck to the driving position in front of the casing (2). The second degree of freedom allows the extension to be then rotated about the driving axis of a drill drive shaft (5) so that the displaced chuck is moved from an upwardly-pointing position to a downwardly position directly in front of the pistol grip. The interchanging of the chucks (20, 21) can be controlled by the hand of the user holding the hand grip (4).