Patent GB-348331-A (GB)
Title: Improvements in or relating to automatic welding apparatus
IPC: B23K5/06
Filed: 1930-04-09
Abstract: 348,331. Uniting by fusion. SVENSKA AKTIEBOLAGET GASACCUMULATOR, Lidingo, near Stockholm. April 9, 1930, No. 11288. Convention date, May 1, 1929. [Class 83 (iv).] An oxyacetylene or electric arc-welding apparatus for welding straight or circular joints, which is supported by and traversed on the work by mechanical means is provided with improved guiding means. The apparatus, which is provided with a handle 69 for transport purposes, may be traversed by a motor 1 mounted on the frame 15 and driven electrically, hydraulically, or by internal combustion, compressed air or welding gases, or may be driven by external power. The motor may be arranged to drive traversing wheels 13 by worm gear 2, 3, friction disc 4, roller 5 adjustable by a screw 8, friction disc 6 and worm gear 9, 11, 12. Wheels 59 are arranged at the front of the apparatus. A cog wheel and cog track may also be used, the apparatus being supported by wheels or on a slide. The motor shaft carries a fan 16, which constitutes the principal load on the motor so as to obtain substantially constant speed. This fan also serves to cool the apparatus and also the work. The blowpipe 22 and welding rod 32 are carried by a shield 17 to prevent damage to the apparatus by the burner and to deflect the air from the fan for cooling purposes. Holes 17a are provided for the passage of air through the shield. The shield is laterally adjustable in the frame and is also adjustable by a screw 77 engaging lugs 76, 75 for use in welding circular joints. The blowpipe 22 is carried by a pipe 21, which is keyed to a sleeve 26 rotatably adjustable by worm gear in a sleeve 27 also adjustable by worm gear about a pivot 28. The sleeve 26 contains a spring 24 engaging a flange 23 on the pipe and is also provided with a nut 25 to adjust the blowpipe vertically. The welding rod 32 is mounted in spring-pressed pivoted jaws 30, 31 in a lever 63, which is oscillatable about a pivot 40 by a pin 47 engaging a flanged collar 46 on a shaft 44 reciprocated against the action of a spring 45 by an inclined surface on the rear of the disc 6 through a roller 42 on an arm projecting from the shaft. The shaft may be rotated by worm gear to adjust the amplitude of the oscillations. The rod is fed by rollers 33, 34 driven through a flexible shaft from a roller 38, carried by an adjustable arm 38a and engaging a friction disc 39 driven by a worm wheel 62 from the worm 11. A series of rollers 50, 51, 52 may be guided either in a groove at the joint or in a grooved piece mounted thereon parallel with the joint, or grooved rollers may be used to engage a flanged joint. The rollers are carried by arms 53, 54, 55 pivoted on shafts 56, 57, 58 and may also move in guides. If the joint is previously tack or spot welded the distance between the rollers must be greater than the length of the spot weld. In welding the bottoms of cylindrical vessels, the wheels 50, 51, 52 may be moved laterally on the shafts 56, 57, 58 by a member 60 so that both pairs of wheels 13, 59, may be arranged on the same side of the seam. In this case also the shield is moved laterally and the pin 47 engaged with a second collar 46a on the shaft 41. A grooved bracket 72, Fig. 8, may be used to guide the apparatus right to the end of the seam. In operating on circular joints the work may be rotated continuously or intermittently m the opposite direction to the apparatus. The jaws 31 may also carry a spring- operated hammer 64, Fig. 5, raised by a cam 67 driven by a flexible shaft 68 from the motor in order to finish the joint. The edges of thin work may abut each other in which case additional metal is not required to effect the weld.