GB548645A - Improvements in rod feeding devices for automatic welding apparatus - Google Patents

Abstract

548,645. Uniting by fusion. LINDE AIR PRODUCTS CO. Nov. 1, 1941, No. 14083. Convention date, Nov. 13, 1940. [Class 83 (iv)] A device for feeding a coiled welding rod or wire in an automatic electric arc or gas welding apparatus, comprises a jaw plate with a longitudinally curved surface for engaging and imparting a predetermined curvature to the rod. The rod is thus fed to the welding puddle at an angle other than a right angle so that a momentary change in the speed of the rod does not appreciably change the distance between the end of the rod and the work. The conditions in the welding zone in an arc welding apparatus are thus substantially stabilized. The device comprises a two part handle or bracket 10, 12 in which is mounted an electric motor M which through reducing gear rotates a feed roller F co-operating with a pressure roller P normally pressed forward by an adjustable spring 32 but retractable by a hand operated eccentric 42 to permit the rod to be threaded between the rollers. To the portion 12 of the bracket is secured by screws a bus bar provided with terminals 48 connected by cables 74 to a terminal box 70 having switches 76 for controlling the motor and flow of current to the welding rod. To a vertical surface on the forward end of the bus bar is secured by bolts 54 and slots 56 a contact jaw J which has a longitudinally grooved curved surface 51 co-operating with a pair of spring- pressed rollers S mounted in the bracket to bend the rod in a radius slightly smaller than that of the rod as it is drawn from the reel R. Each slot 56 is formed about one of the bolts 54 as a centre so that the jaw may be adjusted so as to feed the welding rod to the work at any desired angle.