A tool for roughening a borehole surface. The tool includes a coupling portion for clamping the tool in a drilling machine; and a tool head for machining the borehole surface, where the tool head comprises a cutter that is circumferentially disposed on the tool head, and where the tool head has at least one slit, which passes through from one side to the other and which, starting from an end face of the tool head, and extends axially along a longitudinal axis of the tool.

The present disclosure provides for a system to secure an anchor within a bore hole comprising a drill bit tool to be connected and secured to an improved setting tool head. The system is also comprised of an anchor removably secured to the setting tool head to optimize the setting strength of the anchor. The system is also comprised of bullets having preferred size ranges to further optimize the setting of various anchors.

A hole drilling device for forming an expanded-diameter hole portion at an inner bottom part of a mounting hole includes: a shaft including a contact surface and a tapered surface, and a cutter including a stopper provided on a side surface of the cutter, the stopper coming into contact with a surface of a drilling object. The cutter is movable between a first position and a second position. When the cutter is in the first position, the contact surface is in contact with the inner bottom part of the mounting hole, and the stopper is away from the surface of the drilling object. When the cutter is in the second position, the cutter has been pushed in forward from the first position, the cutting bit has protruded laterally from the tapered surface, and the stopper is in contact with the surface of the drilling object.

A diameter expansion drill bit used to expand the diameter of a part of a prepared hole bored in a frame by grinding includes: a cutting-blade portion that has a plurality of separate cutting-blade portions; a cutting-blade holding portion that slidably holds the plurality of separate cutting-blade portions in a radial direction; and a shank portion that supports the cutting-blade holding portion. The plurality of separate cutting-blade portions is arranged in a peripheral direction and arranged over a plurality of stages in a shaft direction, and the plurality of separate cutting-blade portions of the respective stages is caused to slide by a centrifugal force resulting from rotation so as to spread to an outside in the radial direction with respect to the cutting-blade holding portion.

A tool for roughening a borehole surface. The tool includes a coupling portion for clamping the tool in a drilling machine; and a tool head for machining the borehole surface, where the tool head comprises a cutter that is circumferentially disposed on the tool head, and where the tool head has at least one slit, which passes through from one side to the other and which, starting from an end face of the tool head, and extends axially along a longitudinal axis of the tool.

The invention relates to a drill head for chambering a blind hole with a flat base, and a method directed thereto.

A device for drilling a hole with an expanded diameter includes: a body, a shank; a sleeve; a compression spring; a drill bit body; an expanded diameter hole portion forming member attached to a side surface of the drill bit body and configured such that a cutting bit protrudes laterally from the drill bit body when the expanded diameter hole portion forming member moves forward on the side surface; a compression spring, which urges the expanded diameter hole portion forming member rearward relative to the drill bit body; and a cam. The expanded diameter hole portion forming member is configured to move forward on the side surface of the drill bit body owing to rotation of the cam when the body moves forward relative to the sleeve.

A hole expansion device includes a cutting portion main, body formed to have a diameter for the cutting portion, main body to be housed within a joint hole and including a cutting blade tool movable in a range from a housed position at which a blade is housed within a diameter for the cutting portion main body to an extended position at which the blade projects out of the diameter, an advancing and retracting member that is constructed to move in an axial direction by an external force and rotate about an axis of the advancing and retracting member, and a link mechanism that converts an advancing and retracting movement of the advancing and retracting member into a rotational movement of the cutting blade tool.

A diameter expansion drill bit used to expand the diameter of a part of a prepared hole bored in a frame by grinding includes: a cutting-blade portion that has a plurality of separate cutting-blade portions; a cutting-blade holding portion that slidably holds the plurality of separate cutting-blade portions in a radial direction; and a shank portion that supports the cutting-blade holding portion. The plurality of separate cutting-blade portions is arranged in a peripheral direction and arranged over a plurality of stages in a shaft direction, and the plurality of separate cutting-blade portions of the respective stages is caused to slide by a centrifugal force resulting from rotation so as to spread to an outside in the radial direction with respect to the cutting-blade holding portion.

A hole expansion, forming device includes a cutting portion main, body formed to have a diameter for the cutting portion, main body to be housed within a joint hole and including a cutting blade tool movable in a range from a housed position at which a blade is housed within a diameter for the cutting portion main body to an extended position at which the blade projects out of the diameter, an advancing and retracting member that is constructed to move in an axial direction by an external force and rotate about an axis of the advancing and retracting member, and a link mechanism that converts an advancing and retracting movement of the advancing and retracting member into a rotational movement of the cutting blade tool, a tip portion bearing that is provided on a tip end of the cutting portion main body, and serves as a tip end side bearing when being housed in an inner side of the joint hole.