| 摘要 |
A setting device arranged to use caseless propellent charges for driving fastening elements, such as bolts, nails and the like, into a hard receiving material includes a casing containing an axially slidable barrel forming a feed element at its rearward end. A counterpressure member is slidably movably supported within the casing and in combination with the end face of the feed element forms a combustion chamber for the caseless propellent charges. When the feed element is displaced rearwardly and forms a part of the combustion chamber, a ring located within the housing encircles its outside surface. The ring has a radially outer frusto-conical surface in contact with a complementary frusto-conical surface on the housing. When a caseless propellent charge is fired, propellent gases contact the ring and displace it along the frusto-conical surface on the casing causing it to be forced into sealing contact with the outside surface of the feed element. |
