Safety device for pneumatic screwdriver - has switching arrangement providing both pneumatic pressure and electric contact to allow screwdriver to start

摘要

The device controls the safe start of a pneumatic, or other mechanically driven screwdriver(6), or a similar rotary implement. It has a frame with a height-adjustable arm (4). The device operates in conjunction with an electrically conductive workpiece(11). A pressure on the screwdriver etc. spindle starts its drive. An additional switching device provides an electric connection between the screwdriver etc. and the workpiece, which deblocks the pneumatic drive and permits the screwdriver operation. If the electric connection has been broken, the holding arm is reset upwards, even if the driving pressure is on.