Patent ID: 8327948
Filing Date: 2012-12-11
Classification: B25D

Abstract:
1. An electric hand tool device, a percussion drill, or a drill hammer, the device comprising: an elongated housing having a front region and a rear region; a spindle disposed within said housing and extending in an axial direction through said housing from said rear region to said front region, said spindle having a front end for engagement with a tool support at said front region of said housing; a drive motor disposed in said housing and cooperating with said spindle for drilling rotation of said spindle about an axial spindle axis; percussion means cooperating with said spindle for axially displacing said spindle in a percussion mode, said percussion means comprising a percussion component having a first cam surface facing said front region of said housing and a beater axially fixed to and rotating along with said spindle, said beater having a second cam surface cooperating with said first cam surface in a percussion mode; an adjusting means, said adjusting means comprising a rear cam member, a pressure member, and a switch ring disposed about said spindle between said rear cam member and said pressure member, wherein said rear cam member is fixed to said housing in said rear region thereof, said rear cam member having a third cam surface facing said front region of said housing, said third cam surface having cam structures extending through an angular region about said spindle axis, wherein said pressure member has a fourth cam surface facing said rear region of said housing, said fourth cam surface having cam structures extending through said angular region about said spindle axis, said pressure member having a front surface cooperating directly or indirectly with said spindle for axial displacement thereof said switch ring having a fifth cam surface on a rear end face thereof and a sixth cam on a front end face thereof, wherein, in a percussion mode and in response to pressure exerted on a work piece, said fifth cam surface seats in stationary meshed engagement with said third cam surface and said sixth cam surface seats in stationary meshed engagement with said fourth cam surface as said spindle is urged towards said rear region of said housing thereby permitting said second cam surface of said beater to cooperate with said first cam surface of said percussion component, wherein, in a drilling mode, said switch ring is rotated about said spindle axis and out of meshed engagement with said third and said fourth cam surfaces to urge said pressure member and said spindle towards said front region of said housing, thereby leading to disengagement between said first cam surface of said percussion component and said second cam surface of said beater; and a spring cooperating with said pressure member to urge said pressure member away from said switch ring.