Claims
- 1. A setting device adapted to use an explosive powder propellent for driving fastening elements, such as bolts, nails and the like, into a hard receiving material with the powder propellent being in the form of caseless propellent charges, comprising a casing having a front end and a rear end, means within said casing for forming an axially extending combustion chamber with the axis of said chamber extending transversely of the front end of said casing and said combustion chamber having a first end and a second end spaced apart in the axial direction of said chamber and an axially extending side wall extending between the first and second ends of said combustion chamber, said means comprising an axially extending feed element displaceably positionable in the axial direction of said combustion chamber within said casing and having a first end and a second end with the first end closer to the front end of said casing than said second end, an axially extending counterpressure member in axial alignment with said feed element and having a first end and a second end, said counterpressure member located closer to the rear end of said casing than said feed element, the second end of said feed element forming said first end of said combustion chamber and the first end of said counterpressure member forming said second end of said combustion chamber and the first end of said counterpressure member arranged to provide surface contact across the end thereof with the caseless propellent charge located within said combustion chamber, said counterpressure member being axially slidably displaceable within said casing in the axial direction of said feed element by said feed element displacing the propellent charge, said casing forming said side wall of said combustion chamber, said counterpressure member having a frusto-conical surface thereon encircling the axis of said counterpressure member with said frusto-conical surface spaced from and between the first and second ends of said counterpressure member and tapering inwardly in the direction away from said feed element toward the second end of said counterpressure member and being axially slidable relative to said casing, means located within said casing between said frusto-conical surface and the rear end of said casing for biasing said counterpressure member in the axial direction toward the front end of said casing and said casing having a stationary frusto-conical surface therein diverging toward the front end of said casing and being complementary to said frusto-conical surface on said counterpressure member and arranged to receive said frusto-conical surface on said counterpressure member in sealing contact with said frusto-conical surfaces having exactly the same cone angle, the complementary said frusto-conical surfaces on said counterpressure member and said casing being ground together in engagement with one another for providing a sealing quality as high as possible, said counterpressure member having an axially extending cylindrically shaped larger diameter section extending from the first end thereof to the larger diameter end of said frusto-conical surface thereon and an axially extending cylindrically shaped smaller diameter section extending from the smaller diameter end of said frusto-conical surface toward the second end thereof, and said larger and smaller diameter sections extending from said frusto-conical surface being in axially sliding surface contact with said casing as said frusto-conical surface approaches sealing contact with the stationary frusto-conical surface of said casing, whereby said biasing means biases said frusto-conical surface on said counterpressure member in the axial direction toward the front end of said casing and out of engagement from said frusto-conical surface on said casing, and when said feed element is displaced toward the rear end of said casing said feed element forms the first end of said combustion chamber, said counterpressure member moves axially in sliding contact with the surface of said casing forming the side wall of said combustion chamber toward the rear end of said casing and said frusto-conical surface on said casing forms a stop for the axial displacement of said counterpressure member moving toward the rear end of said casing and in the stopped position said frusto-conical surfaces are disposed in stationary contacting engagement and form a seal for propellent gases when a caseless propellent charge is ignited within said combustion chambers, ignition means being located within said casing for firing a caseless propellent charge positioned within said combustion chamber, said ignition means being located within said counterpressure member, and said ignition means comprises an ignition electrode.
Priority Claims (1)
Number |
Date |
Country |
Kind |
3005342 |
Feb 1980 |
DEX |
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Parent Case Info
This is a continuation of application Ser. No. 505,120 filed June 20, 1983 which in turn was a continuation of application Ser. No. 233,186 filed Feb. 10, 1981, now abandoned.
US Referenced Citations (2)
Foreign Referenced Citations (2)
Number |
Date |
Country |
56646 |
Mar 1965 |
AUX |
1110499 |
Apr 1968 |
GBX |
Continuations (2)
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Number |
Date |
Country |
Parent |
505120 |
Jun 1983 |
|
Parent |
233186 |
Feb 1981 |
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