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along the angular wall, thereby relieving the force exerted onto the shank by the wall and allowing the shank to be withdrawn.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 reverse spot-facing tool for cutting a reverse spot-face in a workpiece using a reverse spot-facing cutter configured to engage a pilot shaft having a first end and a second end is disclosed. The workpiece comprises a through hole having a central axis. The reverse spot-facing tool comprises a stop configured to be located between the first end and the second end of the pilot shaft; a biasing assembly that generates a first thrust force and an equal and opposite second thrust force when the reverse spot-facing cutter is cutting the reverse spot face; and a thrust bearing configured to be positioned between the biasing assembly and the stop. When the reverse spot-facing cutter is cutting the reverse spot-face, the thrust bearing transmits the second thrust force from the biasing assembly to the stop, and the biasing assembly transmits the first thrust force to the workpiece.

The invention relates to an expanding clamping sleeve for an expanding chuck having a first and a second bearing section, a clamping section that can grasp a tool, and a thrust section that is arranged between the clamping section and the first bearing section. The invention further relates to a toolholder having such an expanding clamping sleeve, wherein a contact surface is provided for a tool-side stop. The invention finally relates to a method for clamping a tool using an expanding chuck, in which, in a first step, a shaft of the tool is inserted into the expanding chuck, then the expanding chuck is subjected to pressure so that a clamping section of the expanding chuck clamps the tool shaft in the radial direction, and a thrust section of the expanding chuck displaces the tool shaft in the axial direction so that a tool-side stop is forced against a contact surface of a toolholder with an axial minimum clamping force.

A clamping device for clamping a workpiece or a tool or a tool holder to a machine component of a machine tool, having an axially movable tension rod, a clamping assembly which can be moved by the tension rod between a clamped position and a released position, a spring assembly dedicated to the tension rod with a plurality of series-connected spring units for generating the clamping and draw-in force of the clamping assembly, and a releasing unit by which the clamping assembly can be moved by the tension rod against the force of the spring assembly into the released position. To ensure the most uniform load possible, the axial spring deflection of the spring units is limited by a stop when the spring assembly is compressed.

A clamping device for clamping a workpiece or a tool or a tool holder to a machine component of a machine tool, including an axially movable tension rod, a clamping assembly which can be moved by the tension rod between a clamped position and a released position, a spring assembly dedicated to the tension rod for generating the clamping and draw-in force of the clamping assembly, and a releasing unit by which the clamping assembly can be moved by the tension rod against the force of the spring assembly into the released position. The spring assembly has a minimum of one spring unit with a plurality of flexible spring members disposed between a first and a second spring holder, with the first and second spring holders being secured against torsion relative to the tension rod.

A reverse spot-facing tool for cutting a reverse spot-face in a workpiece using a reverse spot-facing cutter configured to engage a pilot shaft having a first end and a second end is disclosed. The workpiece comprises a through hole having a central axis. The reverse spot-facing tool comprises a stop configured to be located between the first end and the second end of the pilot shaft; a biasing assembly that generates a first thrust force and an equal and opposite second thrust force when the reverse spot-facing cutter is cutting the reverse spot face; and a thrust bearing configured to be positioned between the biasing assembly and the stop. When the reverse spot-facing cutter is cutting the reverse spot-face, the thrust bearing transmits the second thrust force from the biasing assembly to the stop, and the biasing assembly transmits the first thrust force to the workpiece.

A reverse spot-facing tool for cutting a reverse spot-face in a workpiece using a reverse spot-facing cutter configured to engage a pilot shaft having a first end and a second end is disclosed. The workpiece comprises a through hole having a central axis. The reverse spot-facing tool comprises a stop configured to be located between the first end and the second end of the pilot shaft; a biasing assembly that generates a first thrust force and an equal and opposite second thrust force when the reverse spot-facing cutter is cutting the reverse spot face; and a thrust bearing configured to be positioned between the biasing assembly and the stop. When the reverse spot-facing cutter is cutting the reverse spot-face, the thrust bearing transmits the second thrust force from the biasing assembly to the stop, and the biasing assembly transmits the first thrust force to the workpiece.

A clamping device for clamping a workpiece or a tool or a tool holder to a machine component of a machine tool, including an axially movable tension rod, a clamping assembly which can be moved by the tension rod between a clamped position and a released position, a spring assembly dedicated to the tension rod for generating the clamping and draw-in force of the clamping assembly, and a releasing unit by which the clamping assembly can be moved by the tension rod against the force of the spring assembly into the released position. The spring assembly has a minimum of one spring unit with a plurality of flexible spring members disposed between a first and a second spring holder, with the first and second spring holders being secured against torsion relative to the tension rod.

A clamping device for clamping a workpiece or a tool or a tool holder to a machine component of a machine tool, having an axially movable tension rod, a clamping assembly which can be moved by the tension rod between a clamped position and a released position, a spring assembly dedicated to the tension rod with a plurality of series-connected spring units for generating the clamping and draw-in force of the clamping assembly, and a releasing unit by which the clamping assembly can be moved by the tension rod against the force of the spring assembly into the released position. To ensure the most uniform load possible, the axial spring deflection of the spring units is limited by a stop when the spring assembly is compressed.

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.