Abstract: A rupturable can member (10) of sheet metal has a pair of scorings (16) which define a tearing strip (18) laterally. Welded onto the tearing strip (18) is a tongue (20) which has a thickened portion (24) at its welded-on end (22). This thickened portion is formed by a margin folded back towards the other free end (26) of the tongue (20).

Abstract: A method of fabricating a projection for resistance welding contemplates fabricating the projection at the workpiece by plastic deformation of the basic material and dimensionally exactly shaping the projection by compression molding of the flowable metal between a punch and die of a tool.

Abstract: A rupturable can member (10) of sheet metal has a pair of scorings (16) which define a tearing strip (18) laterally. Welded onto the tearing strip (18) is a tongue (20) which has a thickened portion (24) at its welded-on end (22). This thickened portion is formed by a margin folded back towards the other free end (26) of the tongue (20).

Abstract: For welding tongues (12) onto sheet-metal parts (10), particularly tear-open can parts, a welding machine having at least one pair of welding electrodes (62, 63) is provided. The sheet-metal parts (10) can be moved through the machine steps between the welding electrodes (62, 63), one behind the other, by a sheet-metal conveyor (15) and be located in a defined position by a positioning device (17). The tongues (12) can each be placed against a sheet-metal part (10) between the welding electrodes (62, 63) in synchronism with the working cycle of the sheet-metal conveyor (15) by a tongue conveyor (18).

Abstract: A can body is rolled from a sheet-metal blank (28) and has outer and inner longitudinal edges (12 and 14 respectively) which are welded to one another in an overlapping manner. Extending round the can body transversely to the longitudinal edges (12, 14) are two circumferential scorings (16) which define a tearing strip (18) laterally. The tearing strip (18) is extended by a tongue (20) which is welded onto the outer longitudinal edge (12) and which can be gripped by a key and rolled up. In a welding zone (42) which is adjacent to a starting scoring (30), the tearing strip (18) is stiffened by the welded-on tongue (20) in such a manner that it tears away from the can body reliably along the circumferential scorings (16) during the rolling up of the tongue (20).

Abstract: The leak-tight welding of elongated joints, particularly of circular, interlocked joints, such as, for example, the fluid-tight welding of plugs on drums is achieved by folding over the edge (11), or the circular margins around a circular opening, of the sheet (1) onto which, e.g., a plug (27) or other workpiece is to be welded liquid-tightly, laying the workpiece against the folded-over edge (11), and then applying electrodes (28, 30) on opposite sides of the workpiece and sheet, with sufficient pressure that the folded-over sheet margin (11) is further deformed. In this way, the surface-parts not lying flat against each other at the contact-surface (35/32) of the workpiece and sheet margins are forced into accommodation and an even distribution of pressure along the contact-surface results. When the welding-current is switched on, the current density is essentially uniform throughout the contact-surface and hence a simultaneous welding along the entire contact-surface occurs, producing a a leak-tight joint.

Abstract: On a machine for welding together the longitudinal edges (12, 14) of rounded sheet-metal container body blanks there are disposed a plurality of rings (24) of rollers round a common longitudinal axis (22), one behind the other in the direction of passage through (A) of the blanks (10). At least some (28) of the rollers (26, 28) of the rings (24) of rollers are each mounted on a roller carrier (40) which is adjustable in the direction away from the longitudinal axis (22) against resilient resistance. The roller carriers (40) are guided in a manner which enables the associated rollers (28) to execute yielding movements at an angle of distinctly less than 90.degree. to the direction of passage through (A) of the blanks (10). For this purpose, the roller carriers (40) are each pivotable about a transverse pin (42) which is disposed at least substantially parallel to the associated roller spindle (38), upstream of this with respect to the direction of passage through (A) of the blanks (10).

Abstract: A rupturable can member (10) of sheet metal has a pair of scorings (16) which define a tearing strip (18) laterally. Welded onto the tearing strip (18) is a tongue (20), which has a thickened portion (24) at its welded-on end (22). This thickened portion is formed by a margin folded back towards the other free end (26) of the tongue (20).

Abstract: For the welding of tongues (12) onto rupturable can members (10) of tin plate, a pair of welding electrodes (20, 22) is provided which are movable cyclically towards and away from one another and are additionally movable cyclically transversely to this movement in such a manner that successive spot welds are carried out by different portions of electrode.

Abstract: A can body is rolled from a sheet-metal blank (28) and has outer and inner longitudinal edges (12 and 14 respectively) which are welded to one another in an overlapping manner. Extending round the can body transversely to the longitudinal edges (12, 14) are two circumferential scorings (16) which define a tearing strip (18) laterally. The tearing strip (18) is extended by a tongue (20) which is welded onto the outer longitudinal edge (12) and which can be gripped by a key and rolled up. In a welding zone (42) which is adjacent to a starting scoring (30), the tearing strip (18) is stiffened by the welded-on tongue (20) in such a manner that it tears away from the can body reliably along the circumferential scorings (16) during the rolling up of the tongue (20).

Abstract: A welding machine with wire electrodes is used to electrically resistance roll seam weld tin plate. Only one electrode wire running over both of the electrode carrying rolls is used. To prevent the formation of a loop in the wire stretch between the electrode carrying rolls a hard wire is required which is produced by a prior rolling of a soft round wire. With this rolling there results however a non-uniform hardness distribution over the wire cross section with areas of high and areas of low material hardness so that the average strength increase over the entire wire cross section of the electrode wire remains below the increase in strength which could theoretically be reached if no portion of the wire cross section remained outside of the area of high material strength.

Abstract: In a method for electrical resistance roll seam welding with a single electrode-wire, wherein the electrode-wire runs over first and second electrode carrier-rolls urged against each other, and the strength of the electrode-wire is increased by rolling-out before it enters the first electrode carrier-roll, elongations of the electrode-wire which can otherwise arise and lead to a slippage of the electrode-wire at the welding point and therefore, deleteriously affect the weld-quality can be largely prevented by reducing the electrode-wire temperature at the welding-point by cooling with a cooling device (17) the electrode-wire (12) between its rolling-out point (17/18) and its passage onto the first electrode carrier-roll (14) and/or between its departure from electrode carrier-roll (14) and its passage onto the second electrode carrier-roll (15).

Abstract: A projection for use in electrical resistance welding of sheet metals and thin-wall parts, a method of fabricating such projection and the use of the same are disclosed. The flanks of the projection possess internally thereof an angle of about 40.degree. to 75.degree. and externally an angle of about 40.degree. to 100.degree., and the strength of the material at the region of the flanks is about 50% greater than the strength of the neighboring basic material. The method of forming the projection contemplates fabricating the same through plastic deformation of the basic material and the dimensionally exact shaping is accomplished by compression molding of the flowable metal between a punch and die of a tool.

Abstract: A method of transporting can bodies for a fully automated resistance welding machine comprising a roll former station for rolling the bodies, two successively arranged driven transport systems, and a pair of welding electrodes. The transport systems comprise endless, revolving chains equipped with fixed catches or cams and defining first and second chains. The first chain passes through the roll former station where, during rolling of the blanks into the can bodies, it cyclically and periodically remains at least approximately stationary, whereas the second chain has a sinusoidal velocity course. The can bodies exposed to the intermittent non-continuous mode of operation of the first chain, necessitated by the roll forming operation, are transferred to the second chain and experience a movement which is stabilizing for the can bodies.

Abstract: An apparatus for the application of a protective coating to the welded or soldered seam of can bodies. Two driven rolls arranged in tandem or series apply a protective coating, typically in the form of a lacquer, to the seam of the cans or can bodies. One of the rolls covers the actual seam and the other roll covers the region neighboring the seam. Both effective regions of the rolls overlap laterally of the seam at critical locations where the protective coating is to be applied to the seams of the can.

Abstract: A transport installation and method of transporting can bodies for a fully automated resistance welding machine comprising a roll former station for rolling the bodies, two successively arranged driven transport systems, and a pair of welding electrodes. The transport systems comprise endless, revolving chains equipped with fixed catches or cams and defining first and second chains. The first chain passes through the roll former station where, during rolling of the blanks into the can bodies, it cyclically and periodically remains at least approximately stationary, whereas the second chain has a sinusoidal velocity course. The can bodies exposed to the intermittent non-continuous mode of operation of the first chain, necessitated by the roll forming operation, are transferred to the second chain and experience a movement which is stabilizing for the can bodies.

Abstract: An apparatus for resistance welding of the longitudinal seam of can bodies by means of electrode rollers which are suspended so as to be oscillatingly drivable transversely with respect to the edges of the can bodies which are to be welded, in order to prevent premature wear of the electrode rollers due to the formation of notches, scoring or the like. The lower electrode roller which is additionally oscillatingly or reciprocatingly suspended in vertical direction provides outstanding accessibility and low dead mass of the moved parts.

Abstract: An apparatus for applying a protective coating to the inside of the welded seam of cans. When fabricating cans which are provided at their inner surface with a protective coating it is necessary, following the welding operation, to apply to the region of the welding seam the then missing part of the protective coating. Prior techniques were unable to achieve any optimum application of the seam-coating which would reliably cover the welded seam. If the fabricated cans are particularly intended for use for canned foods this then is dangerous to the health of the user. With the apparatus of the invention the protective coating is applied by means of a driven applicator roll to the welded seam. By suitably selecting the outer or jacket surface of the roll and a scraper as well as the rotational speed of the roll it is possible to optimize application of the protective coating.

Abstract: A resistance welding machine for seam welding blanks or bodies or the like, comprising a guide device arranged in front of the electrode rolls for producing an exactly determined overlapping of the edges of the blanks or bodies and for guiding the overlapped blank edges to the welding point between the electrode rolls. Adjustment of a movable section of the guide device aligns the guide device at the welding point.

Abstract: Method and apparatus for longitudinally seam welding overlapped edges of metal sheets with continuously renewable flat wire electrodes in which the edges are overlapped a distance of from three to no more than six times the thickness of the edges and the flat wire electrodes have a width from about two to three times the width of the overlap.