Patent ID: 6681869
Filing Date: 2004-01-27
Classification: B23B

Abstract:
A hand-held rotary-percussion borer comprising an electrical drive (2) for generating a torque transmittable to a boring tool used with the borer for forming blind bores; a hammer mechanism (3) for applying axial impacts to the boring tool; controls means (7, 7â€² and 7â€³) for controlling operation of at least one of the electrical drive (2) and the hammer mechanism (3); and an electronic depth stop (4) including a sensor (5) for contactless, distance measuring of a depth of a blind bore, and a computation unit (6) for generating a signal indicating that a sensed measurement value (M) corresponds to a set value of a depth of the blind bore, and connected with the control means (7, 7â€², 7â€³), the control means, 7, 7â€², 7â€³) reducing an impact for the hammer mechanism (3) while maintaining the torque transmittable to the boring tool in response to the indicating signal.