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: Spot- and projection-welding of aluminum sheets has always been connected with difficulties mainly because of the surface layers of aluminum oxide, and even by pickling, these difficulties could be only partly eliminated. The main difficulties have always been insufficient electrode life times, the unsatisfactory quality of the weld and especially the unsolved problem of achieving good quality welding and long electrode-life when using un-pretreated aluminum sheets. The problem has been solved in principle by using electrodes having profiled contact-surfaces, by means of which the layer of oxide is broken during pre-pressing and a direct contact between the electrode and unoxidized material of the workpiece is provided, the contact-resistance of which is lower than the portion of the overall resistance of the point of weld formed by the metal of the aluminum sheets to be welded together.
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).
Type:
Grant
Filed:
January 25, 1984
Date of Patent:
August 20, 1985
Assignee:
Paul Opprecht
Inventors:
Paul Opprecht, Wolfgang Weil, Martin Kaul
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: In an apparatus and a method of at least partially suppressing oxidation of can components or the like during resistance roller welding with the aid of an inert gas, the steps include welding the can components to one another, so as to obtain a hot welding seam, supplying the inert gas to the hot welding seam so as to envelop it at least partially, and to create a region of the inert gas in contact with the surrounding atmosphere, so that oxidation of the hot welding seam is at least partially suppressed.
Type:
Grant
Filed:
December 3, 1980
Date of Patent:
July 26, 1983
Assignee:
Paul Opprecht
Inventors:
Wolfgang Weil, Andres Lanz, Max Vogt, Paul Meier, Martin Kaul, Hanspeter Fankhauser
Abstract: An apparatus for transporting successive pieces to be separated from one another at respective predetermined spacings at a predetermined velocity, includes a rotary-to-linear movement conversion device, including a crank normally arranged to be driven at a prearranged angular velocity by a drive mechanism, and a clutch normally connected to, but disconnectable from the crank, and adapted to be connected to a drive device for periodically reducing the angular velocity to zero, so that the spacing of successive pieces may be accurately adjusted.
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.