Electric spindle for numerically controlled machine tools

摘要

An electric spindle of a numerical control machine configured to lock and rotate the tool (100) about a predetermined reference axis (A) that locally coincides with the longitudinal axis of the tool (2) (1). The electric spindle (1) comprises an outer structural casing (2) configured to be rigidly attachable to a general numerical control machine; housed in the structural casing (2) and a drive shaft (4 ) Provided with an electric motor (3), and the front end (4a) of the drive shaft (4) is located outside the structural casing (2) and locally with the reference axis (A) of the electric spindle. Projecting / appearing while maintaining a coaxial state. The electric spindle (1) is further connected to a front end (4a) of the drive shaft (4) with a first set of annular rotary bearings (12) interposed therebetween so as to be axially rotatable. A bearing bush or sleeve (11), said sleeve (11) being a second set of annular rotary bearings (between said rotary bush or sleeve (11) and said structural casing (2) ( 13), the electric spindle is maintained coaxially with the reference axis (A). The electric spindle (1) further comprises at least one removable tool configured to be rigid and stable but easily releasably attachable to the front end (4a) of the drive shaft (4) A holder head (5,5 '), said detachable tool holder head (5,5'), although the shanks (101) of a general tool (100) of a numerical control machine are solid and stable It is configured to be housed and held so that it can be easily released. The detachable tool holder head (5, 5 ') is provided with a peripheral crown (14), and the peripheral crown (14) is at the front end (4a) of the drive shaft (4) or , Dimensioned / configured to selectively and alternatively stably contact the rotating thrust bearing bush or sleeve (11).