US2106692A

US2106692A - Gas-arc torch

Info

Publication number: US2106692A
Application number: US92034A
Authority: US
Inventors: Embleton Rowland
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1935-07-26
Filing date: 1936-07-22
Publication date: 1938-01-25
Anticipated expiration: 1955-01-25

Description

Jan. 25, 1938.

R. EMBLETON GAS-ARC TORCH Filed July 22, 1956 2 Sheets-Sheet l Inventcn": Rowland Em letom H is Attorney.

Jan. 25, 1938.

R. EMBLETQN GAS-ARC TORCH Filed July 22, 1936 2 Shets-Sheet 2 Inventor. Rowland Em labor y His Attovney.

Fstsntecl Jan. 25, 1933 iJNiTED STATES PATENT OFFICE GAS-ARC TORCH New York Application July 22, 1988, Serial No. 92,034 In Great Britain July 26, 1985 Claims.

My invention relates to gas-arc torches and more particularly to multi-flame gas-arc torches embodying a plurality of pairs of electrodes.

As pointed out in the United States Letters Patent 1,946,305, James T. Catlett, February 6, 1934, a stable arc may be produced between convergent electrodes by laterally displacing their arcing terminals so that the electrodes are moved from a common plane into two diiferent planes. It is frequently desirable to place a plurality of arcs closely adjacent one another to obtain a combined heating eii'ect particularly suited for certain kinds of welding and an independent adjustment of the several pairs of electrodes becomes diflicult and leads to structural complications.

It is an object o1 my invention to provide a multi-iiame gas-arc torch embodying a plurality of pairs of electrodes arranged in two rows with the electrodes of each pair occupying corresponding positions in said rows and with their arcing terminals adjacent an elongated opening in the nozzle of the torch.

It is a further object of my invention to provide means for collectively moving the electrodes of one of said rows of electrodes relative to the other of said rows of electrodes and for simultaneously laterally displacing the arcing terminals of said electrodes relatively to one another.

Further objects of my invention will become apparent from a consideration of the following description taken in connection with the accompanying drawings and its scope will be pointed out in the appended claims.

In the drawings Figs. 1 and 2 are side and end views of a multi-ilame gas-arc torch embodying my invention and Figs. 3, 4, and 5 are respectively plan, side sectional, and end sectional views of its nozzle construction. Fig. 4 is a section along 4-4 of Fig. 3, and Fig. 5 is a section along 5-! of Fig- 3.

In the embodiment illustrated in the drawings six pairs of electrodes iii are mounted in two rows with the electrodes of a pair occupying corresponding positions in these rows. Each electrode is secured by a clamp H to a block l2 arranged to slide upon one or more guide rods it. To facilitate certain adjustments, the blocks 12 are prefer-ably maintained in frictional engagement with their associated guide rods by spring means or the like. The clamps ll may be insulated from the blocks I2 so that the feeding mechanism, of which the blocks l2 form a part may be maintained at ground potential when the torch is in use. Current is supplied to the clamps ll through conductors H- electrically attached thereto.

Each block I2 is connected to a feed screw l5 and the feed screws of a pair of electrodes are operated simultaneously by a feed motor l8 whose 5 speed may be constant or controlled automatically in accordance with a characteristic of the are maintained between the electrodes. The feed motors it are offset relative to one another and the feed motor for any pair or electrodes rotates a cross shaft l'l through a speed reducing gearing it. These cross shafts are provided at their ends with bevel gears l9, each of which engages a bevel gear 20 forming a part of the feeding mechanisms for the screws [5. 15

The bevel wheels are mounted on external sleeves 2| and are caused resiliently to bear against intermediate collars on these sleeves through the agency of helical springs interposed between these gears and knurled collars 22 on 20 these sleeves. Splitnuts encircling the feed screws ii are attached to and rotated by the sleeves 2|. With this arrangement the feed screws l5 may be fed by the motors it to move the blocks l2 and feed the electrodes l0 attached thereto. The friction clutches constituted by the spring pressed gears 20 and the intermediate collars on the external sleeves 2i afford the required slip for manual adjustment which may be made by rotating the sleeves 2| independently of the motor drive through the agency of their knurled collars 22.

The split nuts encircling the feed screws I! are recessed at their upper ends to receive the rectangular collared ends of sleeves 23 located within sleeves 22. The sleeves 23 loosely ride upon the feed screws l5 and are provided with knurled portions 24 so that by manually rotating these sleeves the split nuts attached to sleeves 2| may be disengaged from the feed screws ii for making quick adjustments of the feed screws and their attached electrodes. The split nuts are normally held in engagement with the feed screws I! by peripherally disposed springs.

The individual feed units of the torch are mounted in pairs on a frame which is supported on a spindle 25 and the torch as a unit may be rotated about this spindle through the agency of a hand wheel 28 mounted on an arm 21 and connected to the spindle through gears 28. The spindle 25 is supported by two arms 21 which are in turn pivotally supported at 28 on brackets 30 forming a support for the torch as a whole. A hand wheel 3| operates a mechanism which reacts on the support for brackets 38 to move the arms 21 and the torch about their pivotal support 23. The two adjustments thus obtained by operation of hand wheels 26 and 3| provide vertical and horizontal adjustments of the nozzle 01' the torch into which the electrodes II! project. These adjustments make it possible for an operator to properly locate the nozzle of the torch over the work 3 which may be a pipe having a longitudinal seam to be welded.

Referring to Figs. 3, 4, and 5 which show in detail the construction of this nozzle, it will be noted that each of the electrodes It extends through a closely fitting bushing 3 of insulating and arc-resisting material, such for instance as steatite, and that these bushings have cylindrical end portions and ball-shaped intermediate portions. These bushings extend through bores or openings in two mounting plates 33, forming a part of the nozzle structure. The bores in these plates are shaped to correspond with the intermediate ball-shaped portions of the electrode bushings so as to form substantially gas-tight seatings therefor. These bushings are adjustably supported in the mounting plates 33 by'clamping plates 34 provided with bores also shaped to conform with the curvature oi the intermediate portions of the bushings, thereby providing another seating cooperating with the seating provided by the mounting plates 33 for rigidly holding the bushings and therewith the electrodes in adjusted positions relative to one another in two rows with the electrodes of each pair occupying corresponding positions in said rows. The mounting plates 33 in the construction illustrated form part of the wall structure of the nozzle and are clamped against the top surface of a hollow member 35 constituting the body portion of the nozzle. A tip 36 is also attached to the body portion of the nozzle on its bottom surface opposite the clamping plates, the arrangement being such that the arcing terminals of the electrodes are located adjacent the elongated opening in this tip.

The mounting plates 33 and their associated clamping plates 34 are provided with openings of sumcient clearance with regard to the clamping bolts 31 by which they are attached to the body portion 01' the nozzle, to permit the desired relative lengthwise adjustment of these plates to secure a simultaneous collective adjustment of the ofiset of the arcing terminals of the electrodes. A suitable mechanical movement, connected to the mounting plates or to these plates and the body portions of the nozzle, may be provided to facilitate this adjustment of the plates relative to one another. Suitable markings on the plates or on the plates or nozzle body may be provided to indicate the amount of displacement of the arcing terminals of the electrodes resulting from the relative adjustment of the mounting plates 33. v

The body portion 35 of the nozzle is formed along that face against which the mounting plates are clamped with a recess 33 which extends all around the nozzle body, thereby providing an annular chamber extending all around the nozzle body. Means including a conduit 33' are provided for supplying a gas such as hydrogen through a bore in the body portion of the nozzle to this annular chamber. Interposed between the mounting plates 33 and the body portion 35 of the torch, there is an annular packing ring or washer 39 which is cut away at its inner periphery to form V-shaped notches which provide spaces between the clamping plates and body portion of the nozzle for the discharge of gas from the annular chamber 33. The size and arrangement of the V-notches are conveniently adjusted so as to provide a uniform film like flow of gas into the hollow inner portion of the nozzle around its whole periphery. This will insure an even flow of gas through the discharge opening of the nozzle and across the arcing terminals of the electrodes. The flow of gas is indicated by arrows in Figs. 3, 4, and 5.

The nozzle body 35 and the nozzle tip 36 may be provided with channels 40 and I through which a cooling fluid may be circulated in the wall structure of the nozzle. Conduits 42 are employed for supplying the cooling fluid to these channels.

The nozzle tip as well as the other portions of the nozzle may advantageously be made of copper or a similar material to avoid the adherence thereto of small ferrous particles which are projected from the molten pool of welding metal during welding.

The nozzle above described forms a closure at the small end of a funnel-shaped housing 43 which encloses the electrodes and the feeding mechanisms therefor. The feed motors It may likewise be enclosed by a housing 44. The housing 43 may be provided with removable side wall portions which close openings therein through which the operator may obtain access to the electrode clamps for the removal and insertion of electrodes.

So long as the arcing terminals of the electrodes are located adjacent the tip of the nozzle, the nozzle construction may be variously modifled. It will, consequently, be apparent that a nozzle having openings adjacent which the terminals of each pair of electrodes are located may be employed, instead of the nozzle with a single elongated discharge opening above described, without in any way departing from the spirit of my invention. The arcing terminals of the electrodes may likewise be located within the nozzle or project a slight amount therefrom so long as they are adjacent the opening or openings in the nozzle through which the gas is discharged.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A gas-arc torch comprising a nozzle having an elongated discharge opening therein, a plurality of pairs of electrodes projecting into said nozzle with their arcing terminals adjacent the elongated opening therein, said electrodes being arranged in two rows with the electrodes of each pair occupying corresponding positions in said rows, and means for collectively moving the electrodes of one of said rows relatively to the electrodes of the other of said rows and for simultaneously laterally displacing the arcing terminals of said electrodes relatively to one another along the elongated opening in said nozzle, said means including relatively movable mounting plates each of which has openings therein for the electrodes of one of said rows of electrodes.

2. A gas-arc torch comprising a nozzle having an elongated discharge opening therein, a plurality oi pairs of electrodes arranged in two rows with the electrodes of each pair occupying corresponding positions in said rows and with their arcing terminals adjacent the elongated opening in said nozzle, means for collectively moving the electrodes of one of said rows relatively to the. electrodes of the other of said rows and for simultaneously laterally displacing the arcing terminals of said electrodes relatively to one another along the elongated opening in said nozzle, said means including relatively movable mounting plates each of which has openings therein for the electrodes of one of said rows of electrodes, and means for producing an even flow of gas through the discharge opening in said nozzle across the arcing terminals of said electrodes.

3. A gas-arc torch comprising a nczzlehaving an elongated discharge opening therein, a plurality of pairs of electrodes arranged in two rows with the electrodes of each pair occupying corresponding positions in said rows and with their arcing terminals adjacent the elongated opening in said nozzle, means for collectively moving the electrodes of one of said rows relatively to the electrodes of the other of said rows and for simultaneously laterally displacing the arcing terminals of said electrodes relatively to one another along the elongated opening in said nozzle, said means including relatively movable mounting plates each of which forms part of the wall structure of said nozzle and has openings therein for the electrodes of one of said rows of electrodes,

and bushings of insulating and arc-resisting material surrounding said electrodes and adjustably mounted in the openings in said mounting plates.

4. A gas-arc torch comprising a nozzle having a hollow body portion and a tip with an elongated discharge opening therein, a plurality of pairs of electrodes arranged in two rows with the electrodes of each pair occupying corresponding positions in said rows and with their arcing terminals adjacent the elongated opening of said nozzle tip, means for collectively moving the electrodes of one of said rows relatively to the electrodes of the other of said rows and for simultaneously laterally displacing the arcing terminals of said electrodes along the elongated opening in said nozzle tip, said means including relatively movable mounting plates placed edge-to-edge on the body portion of said nozzle opposite said nozzle tip, bushings of insulating and arc-resisting material surrounding said electrodes and adjustably mounted in the openings in said mounting plates, a washer having V-shaped notches along its inner periphery and located between said mounting plates and the body portion. of said nozzle, and means for supplying gas to said nozzle through said V-shapeci notches in said washer.

5. A gas-arc torch comprising a nozzle having a hollow body portion and a tip with an elongated discharge opening therein, a plurality of pairs of electrodes arranged in'two rows with the electrodes of each pair occupying corresponding positions in said rows and with their arcing terminals adjacent the elongated opening of said nozzle tip, means for collectively moving the electrodes of one of said rows relatively to the electrodes of the other of said rows and for simultaneously laterally displacing the arcing terminals of said electrodes relatively to one another along the elongated opening in said nozzle tip, said means including relatively movable mounting plates placed edge-to-edge on the body portion of said nozzle opposite said nozzle tip, bushings of insulating and arc-resisting material surrounding said electrodes and having intermediate portions adjustably mounted in the openings in said mounting plates, means for clamping said bushings in adjusted positions in said mounting plate and for clamping said mounting plates to the body portion of said nozzle in adjusted positions relative to one another, a washer having V- shaped notches along its inner periphery and located between said mounting plates and the body portion of said nozzle, means for supplying gas to said nozzle through said V-shaped notches in said washer, and means for circulating a cooling fluid through the wall structure of said nozzle.

ROWLAND EMBLETON.