| 摘要 |
<p>In a compressed air operated device for driving or setting fastening elements into a receiving material, a driving piston is axially displaceable within a cylinder in the device. Two separate supplies of compressed air are provided to the cylinder, one for driving the piston forwardly and the other for moving the piston rearwardly after the completion of the driving action. The parts of the device forming the cylinder are arranged to provide an opening between the cylinder and the exterior of the device. The opening is normally kept closed, however, it is opened when the piston is driven for inserting a fastening element, so that air in the cylinder ahead of the piston can be exhausted to assure the optimum displacing effect of the compressed air acting on the piston.</p> |
