A mandrel assembly includes a mandrel, adapter, and bit coupler. The mandrel includes a shank part axially disposed in the mandrel, an adapter receiver, and a coupler receiver. An internal hole runs axially through the adapter. The coupler includes first and second axial sections, and an axial bit connection hole with a polygonal section proximate to an inner side, and a cylindrical section proximate to an opening. An outer wall of the adapter fits with an inner wall of the adapter receiver. An outer wall of the first section fits with an inner wall of the coupler receiver. An outer wall of the second coupler fits with the internal hole of the adapter. The mandrel transmits torque, via the adapter receiver and coupler receiver, to the adapter and then to a hole saw coupled to the adapter, and to the coupler and then to a bit coupled to the coupler.

A tool bit connectable to a tool. The tool bit including a tool body having a working end portion, an insertion end portion, and an outer surface formed on the insertion end portion. The insertion end portion defines an end of the tool body and configured to be coupled to the tool. The tool bit also includes a non-circular profile formed on the tool body and partially defining the outer surface, and an alignment region positioned between the non-circular profile and the end of the tool body. The alignment region partially defines the outer surface to facilitate alignment of the non-circular profile with the tool.

An accessory tool includes an adapter end having a maximum outer dimension, and a shank coupled to the adapter end. The shank includes a tool engagement portion including a cross section having a maximum outer width, a first reduced portion disposed between the tool engagement portion and the adapter end and having a first minimum outer dimension and a first length, and a second reduced portion formed in the tool engagement portion between the first reduced portion and an end of the shank. The second reduced portion is engaged by the tool to secure the shank to the tool, and has a second minimum outer dimension and a second length. The maximum outer dimension is greater than the maximum outer width. The maximum outer width is greater than the first minimum outer dimension and greater the second minimum outer dimension. The first length is greater than the second length.

An accessory tool includes an effector end and a shank coupled to the effector end. The shank includes a tool engagement portion that is configured to be received within a tool and a reduced diameter portion disposed between the tool engagement portion and the effector end. The shank defines a first length, and the reduced diameter portion defines a second length that is 10% to 45% of the first length.

An integrated drill chuck for installing mine roof bolts includes a single integrated piece, the single integrated piece including a body defining a receiving cavity, where the receiving cavity is configured to receive and secure a bit having a square-shaped end and a bit having a hex-shaped end. A drill for installing mine roof bolts is also disclosed. A method for installing mine roof bolts is also disclosed.

A tool bit holder for connecting a tool bit to a tool includes a tool body having a first end portion configured to connect to the tool, a second end portion, and a hollow interior configured to receive the tool bit. The second end portion defines an end of the tool body. The hollow interior extends through the end. The tool bit holder also includes a non-circular profile formed in the tool body and partially defining the hollow interior. The tool bit holder further includes an alignment region positioned between the end of the tool body and the non-circular profile. The alignment region partially defines the hollow interior to facilitate alignment of the tool bit with the non-circular profile.

A quick-change connecting mechanism and a quick-change screwdriver of the invention. Firstly, a connecting handle and an accommodating cavity are matched in a shaft-hole mode, during actual production and machining, the machining precision of round shafts and round holes is high, the matching and mounting precision of the round shafts and the round holes is much higher than that of hexagonal shafts and hexagonal holes, and thus the axial precision of the connecting handle or screwable tips is ensured after mounting; secondly, longitudinal locking bodies are arranged and longitudinally inserted into locking grooves in an abutting mode under the effect of a sliding sleeve, so that rotation torque is transmitted in the circumferential direction, and the torque of a connecting rod is transmitted to the connecting handle or the screwable tips. Meanwhile, the connecting handle is fixed in the mounting direction and is prevented from falling.

A drill chuck assembly. The drill chuck assembly includes a rapid change mechanism configured to retain a drill bit shank inserted therein. The drill chuck assembly includes a body having a bore with a trilobe cross-section that is configured to receive a triangular and hexagonally shaped drill bit shank, interchangeably. The bore includes a slot positioned in each lobe that slidably contains a detent ball therein. A collar is affixed annularly around the body and defines a channel extending around the body. A sleeve is slidably mounted around the body. The sleeve includes a tapered end that is slidably disposed within the channel and has circular apertures that are in communication with the slots of the bore for reception of the detent balls. The sleeve is spring biased towards the collar, which forces the detent balls against an angular wall within the channel. The angular wall in turn forces the detent balls laterally towards a center of the bore, thereby exerting a force on a drill bit shank inserted into the bore and preventing the withdrawal of the shank from the bore. When the bias force of the sleeve is counteracted by sliding the sleeve about its longitudinal axis, the detent balls move outwardly along the angular wall, thereby relieving the force exerted onto the shank by the wall and allowing the shank to be withdrawn.

A power tool drill/torque head bit connector is configured to be removably attached to a power tool and offers an alternative to changing drill/torque bits. The drill/torque head bit connector further comprises a chuck coupling portion and a bit securement portion for removably accommodating a drill bit or a torque bit. The chuck coupling portion and the bit securement portion are at opposing ends of the drill/torque head bit connector. The chuck coupling portion for coupling to the power tool. The chuck coupling portion having a male coupler configured to couple to a female coupler port of the power tool for receiving drive gear from the power tool. The bit securement portion configured to accommodate various bits and enables faster bit exchanges for drilling and/or torquing.

A wedge anchor setting tool has a drill bit component having a drill tool receiving member and a drill bit member. A polygonal shaped element is located between the two members. A sheath component has an open passage and an opening at the terminus of each end. The first end has a polygonal shape which conforms to the polygonal element and the second end having a polygonal shape which conforms to the shape of the wedge anchor. The method of installation using the tool includes drilling a channel into a wall using the drill bit component. The sheath component is then inserted over the drill bit component and a wedge anchor is inserted into the smaller opening at the second end of the sheath component. The wedge anchor is then drilled into the wall and tightened by the drilling tool to secure an attachment member to the wall.