Abstract: Electric spindle for numerical control machines structured to lock and rotationally drive a tool about a predetermined reference axis locally coinciding with the longitudinal axis of the tool; the electric spindle comprising: an outer structural casing that is structured to be rigidly attachable to a generic numerical control machine; an electric motor that is housed within the structural casing and is provided with a drive shaft, which projects/emerges with its front end outside the structural casing while remaining locally coaxial to the reference axis of the electric spindle; a rotating thrust-bearing bushing or sleeve, which is fitted in an axially rotatable manner on the front end of the drive shaft via interposition of a first set of annular rolling bearings, and is maintained coaxial to the reference axis of the electric spindle by a second set of annular rolling bearings, which are interposed between the rotating bushing or sleeve and the structural casing; and at least one disassemblable tool-holder

Abstract: The centering adaptor is configured to receive a spade type drill bit. The body of the adaptor has three centering arms to engage in a previously drilled smaller hole so that the spade type drill bit is guided along the same centerline to re-drill the hole to a larger diameter.

Abstract: A universal bit adapter includes: an adapting member clamped in a chuck or spindle of a tool having a shank hole longitudinally formed in the adapting member for inserting a tool bit into the shank hole; a sleeve coupled to a front portion of the adapting member for pivotally mounting a control member in a front portion of the sleeve; and a tension spring resiliently held in the sleeve for tensioning a back portion of the control member for normally biasing the control member to allow an axis of a central hole formed through the control member to be eccentrically inclinedly intersected with a longitudinal axis formed in the shank hole in the adapting member for firmly dogging any shank portion of the tool bit in the central hole in the control member regardless of the positioning of the neck portion as recessed in the shank portion of the tool bit.

Abstract: A universal bit adapter includes: an adapting member clamped in a chuck or spindle of a tool having a shank hole longitudinally formed in the adapting member for inserting a tool bit into the shank hole; a sleeve coupled to a front portion of the adapting member for pivotally mounting a control member in a front portion of the sleeve; and a tension spring resiliently held in the sleeve for tensioning a back portion of the control member for normally biasing the control member to allow an axis of a central hole formed through the control member to be eccentrically inclinedly intersected with a longitudinal axis formed in the shank hole in the adapting member for firmly dogging any shank portion of the tool bit in the central hole in the control member regardless of the positioning of the neck portion as recessed in the shank portion of the tool bit.

Abstract: A holder having a quick-connect mechanism actuated by inserting a single- or double-ended tool bit, the tool bit engaging means to force deflection of retaining means, where the retaining means actuate means for engaging the tool bit, and released by manual operation of the retaining means, whereby the tool bit is pushed out from the holder so that the user can operate the tool bit holder using one hand only.

Abstract: The hand-held machine tool has a tool holder (20) provided with a receptacle (19) into which a shaft portion (15) of a tool (16) is axially insertable. The tool holder (20) has a longitudinal axis (11) and includes a guide device (18) for axially guiding the tool (16); a device (23) for rotary slaving of the tool (16); a retaining device (28) for axially securing the tool (16) and a locking member (34) for locking the retaining device (28) in an open configuration for insertion or removal of the tool (16). The retaining device (28) is located in front of the guide device in an insertion direction of the tool (16) in the tool holder (16). The retaining device (28) is provided with an opening (31) for passage of the tool (16) through it.