A device for holding and securing a tool, in particular, a drill bit, on a machine tool, for example, a core drill, including an output shaft for transmitting a torque generated in the machine tool to the tool; and a union nut positioned around the output shaft for detachably connecting the output shaft to an attachment end of the tool. The output shaft includes a locking ring and the union nut includes a washer disk, as well as an attenuator, the washer disk being positioned between the locking ring and the attenuator.

An assembly for tightening and securing includes a first male part and a second female part fitted together, which have complementary forms. The fitting includes at least one contact surface of the first part with the second part. The assembly also includes at least one annular means mounted on the periphery of one of the two parts. The annular means is connected in a translational manner to the part on which the annular means is mounted when the annular means abuts with the part on which the means is mounted, and arranged to interact with a peripheral surface of the complementary part during a rotation of the annular means in relation to the complementary part.

A device for holding and securing a tool, in particular, a drill bit, on a machine tool, for example, a core drill, including an output shaft for transmitting a torque generated in the machine tool to the tool; and a union nut positioned around the output shaft for detachably connecting the output shaft to an attachment end of the tool.

The output shaft includes a locking ring and the union nut includes a washer disk, as well as an attenuator, the washer disk being positioned between the locking ring and the attenuator.