Abstract: A power adjustment for a piston-type powder actuated fastener driving tool wherein a tube is slidably disposed in the barrel of the tool, the tube containing the driving piston of the tool. The tube has a radially inwardly extending flange at its breech end which engages a radially outwardly extending surface on the piston. Means for moving the tube axially of the barrel are provided so that the distance between the flange and firing chamber can be varied whereby the gas expansion chamber between the firing chamber and the rear face of the piston can be varied thereby varying the power with which the piston is driven.

Abstract: An improved indirect-acting powder-actuated fastening tool is provided wherein the power level may be continuously varied and wherein the tool may be discharged only if the muzzle is pressed against the work surface, with the tool substantially perpendicular thereto. A barrel and a barrel breech are adjustably screwed together and telescopically carried by a slide assembly which, in turn, is telescopically carried by the tool receiver. The slide assembly and the barrel are operably connected for corotation, whereby rotation of the slide assembly produces a joint axial displacement, of the barrel and the slide assembly, relative to the barrel breech, to vary the initial volume.

Abstract: The piston return mechanism for a powder actuated piston-type fastener driving tool utilizes a tilting muzzle bushing to engage the fastener driving face of the piston. After the piston has been driven, the muzzle bushing is displaced manually forwardly, by means of a slide, until the muzzle bushing tilts to a position where it can contact the fastener driving face of the piston. The muzzle bushing is then returned breechwardly, pushing the piston in front of it back into the barrel bore to a driving position. When the driving position of the piston is reached, the muzzle bushing cams out of the tilted position into a position where it is coaxial with the piston.

Abstract: A powder-actuated tool is provided with a barrel assembly having two parallel, communicating bores and a piston comprised of joined, offset portions, with one of said portions being adapted to slide in one bore while another portion is sliding in the other bore, whereby it is possible to provide a relatively short tool, capable of setting long fasteners, with continuous centering, of the fasteners, during their displacement.

Abstract: Synthesis of mercaptans by the photochemical reaction of an olefin with hydrogen sulphide in the presence of an initiator constituted by benzophenone, thiobenzophenone or a mixture of the two, preferably accompanied by an organic compound of an element of Group VA of the Periodic Classification. These initiators can carry substituents on either or both of the two benzene rings. The light utilized can have a wavelength of 300 to 600 nm. The process allows various mercaptans to be obtained with good yields.

Abstract: A fastener driving apparatus having a barrel provided with a fastening element guide which is pivotally mounted about an axis orthogonal to the barrel axis in order to introduce a fastening element therein.The fastening element guide is pivotally mounted on a support secured to the barrel, and there is provided a sleeve operative to engage the guide and pivot the same, said sleeve being moveably carried on the support for translation along the barrel axis in such manner that a relative sliding movement between the sleeve and support, causes the engagement of the sleeve and the guide for pivoting of the latter.

Abstract: The present invention relates to a self-closing propellant charge package adapted for use with a gravity operated loading device of a power-actuated tool. The package comprises a tubular body having one end at least partially closed, the other end being open. A portion of the body adjacent the open end is deformed for holding the charges, it being possible to cancel the deformation of this portion to allow passage for the charges. More specifically, at least one cut-out is provided in the deformable portion, the portion being maintained in a deformed state by a resilient ring or other means.

Abstract: A power actuated tool comprising an expansion chamber for the combustion gases of a piece of ammunition placed in a combustion chamber.In the tool at least one substantially radial through hole is provided in the wall of the expansion chamber or of the combustion chamber and a bush which moves relative to the chamber is provided so as to be able to more or less completely expose the hole.

Abstract: A loading device for a power-actuated tool which comprises a fixed support having an open recess adapted to receive the open end of a tubular propellant charge-retaining holder. A movable charge transporter is mounted on the exterior of the tool and contains a through passage which is movable between a charge-receiving position adjacent to the fixed support recess, and a charge-loading position adjacent to the firing chamber of the tool. Charges are gravity fed from the transporter to the firing chamber. The transporter moves to and from the loading position by pivoting through a pre-existing loading port in the tool.

Abstract: The invention concerns a fastening tool employing a caseless munition. The tool includes a cavity for the munition, or explosive chamber, constituting a high-pressure chamber communicating with a low-pressure expansion chamber through at least one passage. The cavity for the munition, or explosive chamber, is formed radially in the very body of the breech, access thereto for loading being located on the periphery of said breech. It is possible to close said access after loading with a closing member, and the passage or passages putting the munition cavity in communication with the low-pressure chamber are formed in said breech.

Abstract: The device comprises on the front end portion of the plunger or piston a retaining ring mounted in the barrel with the interpositioning of a joint in such a way that the bore of the ring is slightly off-center relative to the piston axis when the joint is not deformed.

Abstract: A power-actuated tool for fastening insulation plates to ingot mold surfaces. The tool includes a cocking foot which reciprocates with respect to the tool breech. Reciprocation of the cocking foot cocks the firing pin and opens and closes an ammunition loading window. A double sear is provided so that the tool cannot be air-fired.

Abstract: The recess for the ammunition comprises two blind bores whose width is equal to, or greater than, the thickness of the ammunition and whose depth is similar to, or greater than, the diameter of the ammunition, whereby the said blind bores are connected by a groove issuing over a part of the height thereof which is at least equal to the diameter of the ammunition, while the duct or ducts issue into the bottom of at least one of the blind bores.