USRE14927E - Frank l - Google Patents

Description

F. L. SESSIONS.

APPARATUS FOR ELECTRIC WELDING.

APPLICATION FILED MAY 5. 1919.

14,927. 2 SHEETS-SHEET 1.

- lnvcutor flan/PL Jmz'ons Reissued July 27, 1920.

Gttorncg .F. L. SESSIONS-J APPARATUS run ELECTRIC WELDING.

APPLICATION FILED MAY 5, 191.9. n Reissued July 27, 1920. 14,927.

2 SHEETS-SHEET 2.

31l vcntor flank L. Sam-20225 Gttorncg UNITED isrAre's PATENT-OFFICE.

FRANK L. SESSIONS, or naxnwoon, .omo, ASSIGNOR, BY MESNE assrenmmrrsfiro THE STANDARD PARTS co rrnzw, or CLEVELAND, care, A CORPORATION or 01110,

airamrus FOR ELECTRIC wnnnmo.

26, 1918, Serial No. 231,025.

To all whom it may concern:

Be it known that I, FRANK L. SESSION S, a citizen of the United States, and a rest dent of Lakewood, county of Guyahoga, and State of Ohio, have invented a new and useful Improvement in Apparatus for Electric Welding, of which the following is a specification, the principle of the lnvention being herein explained and the best mode in which I have contemplated applying that principle, soas to dist1ngu1sh it from other inventions.

The present invention relates more particularly to the welding together of the uxtaposed edges of two sheets of metal, or

the abutting edges of one sheet bent into ously, and, if desired, automatically, at the proper rate of speed to insure the expeditious and yet thorough welding of the 101m; between such juxtaposed edges. To'the accomplishment of theforegoing and related ends the invention, then, consists of the steps and means heneinafter fully described and particularly pointed out in the claims.

The annexed drawings and the following description set forth in detail certain steps and mechanism embodying the invention, such disclosed means constituting, however,

but several of the various ways in which the principle of the invention may be used.

In said annexed draw1ngs: Figure l is a side elevational new, more or less diagrammatic in character, i-llustrating an apparatus adapted to weld together the edges of. a metal 'tube in accordance with my improved method;

Fig. 2 is a similar View of a modified form of the apparatus;

Fig. 3 is an elevation of the same as viewed from the right in Fig. 2;

Fig. 4: is a plan View, with parts shown in section, illustrating yet another modification of the apparatus;

Fig. 5 is a side elevational view of such last-named modification; and

Fig. 6 is a cross-sect1on showing the Specification of Reissued Letters Patent. Rei d Ji l 27 19 0 Original No; 1,287,774, dated December 17, 1918; Serial No. 779,674, filed July l8, 1913. Renewed April Application forreissue filed-May 5, 1919-.- Serial No. 295,010.

welding operation on a larger scale and with a further modification, or addition,-in apparatus.

Any suitable feeding means for forcing or pulling the tube A through the welding apparatus proper may be emp-lo ed, but one or more pairs of feed rolls 1,'il ustrated in Figs. 1 and 4 of the foregoing figures, are adapted for carrying out this part of the operation. By means of said feed rolls, the tube is drawn through between two pressure rolls 2 which are disposed so as to tend to force the butt edges of the tube more or less closely together. Disposed directly above these pressure rolls 2 is a suitable feeding device shown as consisting of two rolls S'between which passes a continuous metallic electrode B of indefinite length, such electrode under operating conditions, being initially forced downwardly until it .is in contact with the abutting edges of the tubing" to be welded, then slightly withdrawn so as to form an arc, and being then maintained in such arcing distance.

In the first and simplest form of apparatus illustrated (Fig. 1), a hand wheel 4 is arranged to rotate a Worm 5 that meshes with a worm wheel 6 on one of the rolls 3, and such wire electrode may be fed at any desired rate, to correspond with the rate of feed of the tube by properly rotating saidhand wheel 4. The wire is conveniently coiled on a reel 7 or the like, from which it is drawn by the aforesaid feeding device and a guide 8 of refractory material may be utilized, if desired, to direct the wire to the proper point on the tubing.

Current may be supplied from any suitable source, as a generator 9, and is conveniently conducted to the tubing through the pressure rolls 2 and to the wire electrode through the feed rolls 3. Such current accordingly will pass from the electrode to the respective abutting edges of the tube, or vice versa, as the case may be,-the are formed between the two serving -to heat such edges and the end of the electrode simultaneously. The current will be regulated to develop sufficient heat to gradually melt the electrode and as it thus melts the tubing willbe advanced by means of the feed rolls-so that such melted electrode will be disposed in the joint between the edges. The latter being simultaneously brought to same onto a corresponding temperature, a continuously welded joint is formed which I have found can be made quite satisfactory for all puroses, and in fact superior tothe ordinary utt-welded join The metallic electrode being of an indefinite length, and means being prov ded as just described for continuously feeding the between which the tube A to be welded is passed. To this end, instead of the spindle with hand wheel 4 having a worm gear connection with the roll, I employ a vertically disposed spindle 10 connected with one of said feed rolls by gears 11 and provided at its upper end with a worm 12 that meshes with a worm-gear 13 on one such roll 3, the ratio of the gears 11, 12 and 13 being proportioned to feed the electrode at just the ro er rate to correspond with the rate of ee of the work. It will be understood that the pressure rolls in this construction, as well as in the preceding one, are power driven.

The apparatus illustrated in Figs. 4 and 5 is further elaborated by the inclusion of means for automatically regulating the rate of feed of the wire electrode B to correspond with the progress of the welding operation. In addition to the feed rolls 1 and the pressure rolls 2 which are disposed substantially as before,there is provided in this last form of apparatus a solenoid 14 that is adapted to be actuated by the current flowing through the work and the wire electrode. This solenoid operates a bell-crank 15 which is, in turn, connected to throw in or out a double clutch 16, through which rotative movement is transmitted from a drive shaft 17, to a second shaft 18 that carries one of the feed rolls 3 for feeding the wire electrode. When such clutch is thrown to the right, the feed is direct and at a predetermined speed, while if the clutch 'is thrown to the left the feed is reversed so as to temporarily withdraw the electrode. In the intermediate position of the clutch, which is the one show-n in Fig. 4, the feeding of the electrode will be simply interrupted and such electrode temporarily held stationary. I I

A spring 19, however, is so connected with the bell-crank 15 or other part of the automatic feeding device as to normally tend to throw the clutch into direct, or forward, feed. Accordingly, upon starting up the apthe work, there need be no interparatus, assuming the current to be on, (the circuit connections being controlled by a switch 20), if the shaft 17 is started rotating, the electrode will be fed forwardly until its end actually contacts with thejuxtaposed edges of the tube A, thereby completing the circuit and causing such a flow of current as will actuate the solenoid to throw the clutch into reverse. The reversing of the feed will withdraw the electrode a trifle, just sufficient, in fact, to remove the end of the electrode the proper distance from said edges to establish an arc. With such are established the flow of current from the circuit, although reduced, will still permit the clutch to drive the feed rolls forwardly andthus continuously feed the electrode at a rate capable of maintaining its end within such arcing distance, despite the gradual fusing of the end. The work being progressively advanced past the end of the. electrode, the juxtaposed edges are brought substantially to a point of fusion, as the melted material from the electrode is deposited between the same.

Should the electrode be fed too rapidly, so as to again bring the same into actual contact with the work, the solenoid will be actuated by the increased fiow of current to interrupt the feeding operation, oroven to reverse the same. As soon, however, as the distance of the electrode from the work is restored to normal, the clutch is thrown into the forward feeding position and the operation proceeded with. The operation of the solenoid may be very sensitive so that a very exact control of the feeding operation is secured, the wire electrode being advanced at just the proper speed to give the desired welding effect. The tension of spring 19 may be adjusted by means of a nut 22.

In rolling up the sheet or strip of metal to preliminarily form the tube for use in the ordinary butt-welding operation, it is usual to stretch the outer surface of the sheet so that the juxtaposed edges may lie in substantially the same radial plane with respect to the axis of the tube. For use in the present'improved process, however, it is not necessary to do this, and in fact it is preferable that the edges a be left in their normal state so that they flare a trifle and thus form a sort of trough, as illustrated in somewhat exaggerated fashion in Fig. 6. In other words, the extreme inner portion of the meeting faces will come into closer contact than the outer portion of such faces,

and the fused metal 3 that is deposited from of porcelain or other refractory material This latter so as to form a complete closure for ttie space between such juxtaposed edges.

The arrangement 'ust referred to is also illustrated in said i 6, it being considered unnecessary to il ustrate the means'of supporting the mandrel as these may be readily improvised, and will vary depend in upon whether the tube is preliminarily ro led up in sections of considerable len th, or is continuously rolled up, as the wel mg operation progresses, from a long strip of metal as it comes from the skelping rolls.

Suitable insulation will of course be provided in each of the several forms of apparatus described above, so as to prevent the current from straying. The particular disposition of such insulation, however, is obvlously a matter of indifference and no attempt has been made to show the same in detail in the drawings.

While the several foregoing described forms of apparatus for use in my improved method are illustrated as adapted for welding the edges of tubing together, it will be understood that the apparatus maybe equally well utilized for welding together the juxtaposed edges of separate sheets'or other articles. Accordingly for the purpose of this specification and the following claims, the respective edge portions of the tube may be regarded simply as two metallic articles, although they form part of the same tube. My improved process, however, does find a highly advantageous field of use in the manu acture of tubing, since by means of it tubing of indefinite length can be made from a strip or skelp, being fed through, the welding apparatus, while a metallic electrode, of like-indefinite length is progressively brought into proximity with the contacting or substantially contacting edges of the tube. The current, it will be observed, by reason of the circuit connections employed, is passed through such ed es of the tube and the electrode.

ather modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the steps or mechanism herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed. I

I therefore particularly point out and distinctl claim as my invention:-

1. Iii apparatus for electrically welding tubing, the combination of pressure rolls adapted to maintain the edges of a preliminarily formed tube in substantial contact; means adapted to feed a metallic electrode transversely of such tube toward such edges;

means adapted tofeed such tube longitudinally so as to move such edges progressively past'the end of said electrode; circuit connections for passing a fusing electric current through said electrode to both such edges; a: suitable driver; a clutch for opera-- tively connecting said electrode feeding means with said driver; and electro-magnetic means connected in such circuit and adapted to operate said clutch. 2. In apparatus for electrically welding tubing, the combination of pressure rolls adapted to maintain the edges of a preliminarily formed tube in substantial contact;

means adapted to feed a metallic electrode transversely of such tube toward such edges;

means adapted to feed such tube longitudinally so as to move such edges progressively past the end of said electrode; circuit connections for passing a fusing electric current through said electrode to both such edges; a suitable driver; a clutch adapted qptionally to connect said electrode feeding fn'eansdirectly or reversely with said driver; and electro-magnetic means connected in such circuit and adapted to operate said clutch.

3. In apparatus for continuous electric welding, the combination of means for feeding the work; means for maintaining the edges to be welded'together in substantial contact; rotar means adapted to grip a fusible metallic electrode and feed same transversely of the line of feeding movement of the work; circuit connections for passing a fusing current through said electrode to such edges; and rotary means controlled by the fusing current for automatically regulating the relative feeding movements of said electrode and thework.

4. In apparatus for electrically welding tubing, the combination of means for maintaining the edges of a preliminarily formed tube in substantial contact; rotary means adapted to grip a metallic electrode and 105 feed same transversely of such tube; means adapted to feed the tube longitudinally so as to move such edges progressively past the end of said electrode; circuit connections for passing a fusin current through such 11o electrode to such e' ges; and rotary means automatically controlled by the fusing current in said circuit, for actuating said rotary feeding means.

5. In apparatus for continuous electric Welding, the combination of means for feeding the work; means for maintaining the edges to-be welded together in substantial contact; means adapted to grip a fusible metallic electrode and feed same trans- 120 versely of the line of feeding movement of the work; circuit connections for passing a fusing current through said electrode to. such edges; and'rotary means governed by the fusing current to automatically control 12;, said electrode feeding means so that the rate of feeding of said electrode .will be in accordance with the variations in the fusing current.

welding, a fusible metallic electrode, means to grip said electrode and feed the same toward the work to be welded, circuit connections for passing a fusing electric current through said electrode to the Work, and devices governed by the fusing current to start the arc and to automatically control said electrode feeding means so that the rate of feeding of said electrode will be in accordancte with the variations in the fusing cur- 10 ren Signed by me this 3d day of May, 1919.

FRANK L. SESSIONS.

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