Abstract: A method of releasably connecting together strips of material comprising arranging the strips with surfaces facing each other and forming upwardly deformed areas of the strips above their planes and downwardly deformed areas of the strips below their planes, the deformed areas having intervening tie portions arranged at angles to the planes of the sheets, the tie portions being partially cut out to form tongues and interlining shoulders and remaining connected to the strips between deformed areas whereby upon relative longitudinal movement of the sheets, the tongues are displaced to seal against the shoulders and the inclined tie portions are adjacent to each other.

Abstract: Deformable sheets are mechanically joined by punching and deforming the sheets in such a manner that one sheet is partially severed and the other sheet is correspondingly deformed without being severed. Pressure is applied to the joint, at least partially flattening both of the deformed portions of the sheets, outwardly expanding the partially severed portion of the severed sheet causing its severed edges to extend outwardly beyond the deformed but unsevered edges of the other sheet, thereby locking the sheets together to produce a waterproff sealed joint.

Abstract: A device for fastening superimposed sheets of metal or the like together by punching corresponding portions of the sheets into displaced positions relative to the adjacent areas of the sheets, then spreading one displaced portion of one sheet, under pressure, into interlocking engagement with the adjacent areas of the other sheet while retaining the corresponding displaced portion of the other sheet from spreading under the same pressure.

Abstract: A piercing punch, a piercing die and a swaging punch are displaced relative to each other to produce locking joints by a machine which uses cams, preferably in the form of pairs of mating, wedge-shaped blocks to produce the necessary reciprocating movements of one or more of the three tool elements. A suitable kinematic actuating device, preferably in the form of a toggle linkage reciprocates the third tool element.The interaction of these elements is such that exceptionally favorable conditions for joint formation prevail.

Abstract: Locking joints in hard-to-reach locations are made by a machine which uses a toggle linkage and a camming means to produce not only the joint-forming movements of a piercing punch, piercing die and flattening punch, but also the additional movements of these tool elements necessary to reach the joint location. No displacement of the over-all machine is necessary.

Abstract: A punch and press mechanism is used to interlock two or more overlying sheets of metal, or other material having plasticity or deformable properties, by partially piercing and deforming minor areas of the sheets. The mechanism includes a pierce-and-forming punch, a hollow cylindrical die, and a flattening punch. The die cavity is aligned with, and cooperates with, the pierce-and-forming punch to displace minor areas of the sheets. The flattening punch is slidably movable within the central bore of the die. Adjustment means are included so that the position of the die relative to the flattening punch may be so adjusted that compressive force is applied to the upper displaced minor area at a time when the lower displaced minor area is not confined by the die, whereby the lower displaced minor area is spread while the upper minor area is still constrained.

Abstract: To fasten together two or more overlying sheets of metal or other material having plasticity or deformable properties by partially piercing and deforming minor areas of the sheets, a pierce-and-forming punch is used in cooperation with a double-acting press having two separately actuatable rams. For displacing the minor areas of the overlying sheets, one of the rams carries a hollow cylindrical pierce-and-forming die, the die cavity of which is vertically aligned with, and cooperates with, a pierce-and-forming punch supported in the base. The other of the rams carries a flattening punch which is slidably movable within the central bore of the hollow cylindrical die. Fine adjustment means are included so that the position of the die may be adjusted for different thickness of sheets to be fastened, and also for wear on the die and/or punch.

Abstract: To fasten together two or more overlying sheets of metal or other material having plasticity or deformable properties by partially piercing and deforming sections of the sheets, a fixed pierce-and-forming punch is used in cooperation with a double-acting press having two separately actuatable rams. For displacing sections of the overlying sheets, one of the rams carries a hollow cylindrical pierce-and-forming die the die cavity of which is vertically aligned with, and cooperates with, a fixed pierce-and-forming punch supported in the base. The other of the rams carries a flattening punch which is slidably movable within the central bore of the hollow cylindrical die. The pierce-and-forming die is supported by means which includes fine adjustment means so that the position of the die may be adjusted for different thicknesses of sheets to be fastened, and also for wear on the die and/or punch.