摘要 |
An impacting drill is equipped with an air cushion impacting mechanism and with a tumbling mechanism which is operative for reciprocating the impacting mechanism. The tumbling stroke of the tumbling mechanism and thus the reciprocating stroke of the impacting mechanism is adjustable from zero to a maximum. The tumbling mechanism includes a hub body which is mounted on a holding body rigid with a rotatable shaft. The holding body is centered on an adjustment axis which encloses an acute angle with the axis of the shaft. The hub body is mounted on the holding body for angular displacement about the adjustment axis with attendant adjustment of the tumbling range. Coupling elements connect the hub body with the holding body in the respectively selected angularly displaced position of the hub body on the holding body. There may be provided a stepping switching mechanism between the hub body and the holding body of the shaft, by which an axial displacement of the shaft is converted into angular displacement of the hub body about the holding body. |