US1226639A

US1226639A - Electric welding.

Info

Publication number: US1226639A
Application number: US14940117A
Authority: US
Inventors: Spencer C Cary
Original assignee: Individual
Current assignee: Individual
Priority date: 1917-02-19
Filing date: 1917-02-19
Publication date: 1917-05-22
Anticipated expiration: 1934-05-22

Description

S. C. CARY.

ELECTRIC WELDING.

APPLICATION FILED FEB. 19. I917. 1,226,639. Patented May 22,1917.

w 4 SHEETS-SHEET 1. N

S. C. CARY.

ELECTRIC WELDING.

APPLICATION FILEDFEB. 19. 1917. 1,226,639. Patented May 22,1917.

4 SHEETS-SHEET 2- M anuewfoz S- C. CARY.

ELECTRIC WELDING. APPLICATION FILED FEB. 19. 1917.

Patented May 22, 1917.

4 smears-sneer a.

srENc ne. CARY, or BROOKLYN, NEW YORK.

ELECTRIC WELDING.

Specification of Letters Patent. Patented lIa 22, '7

' Application filed February 19, 1917. Serial No. 149,401.

To all whom it may concern:

Be it known that I, SPENCER don a citizen of the United States, residing at the city of -New York, borough of Brooklyn, county of Kings, and State of New York,

have invented a certain new and useful Electric-Welding, of which the following is a specification.

In the art of welding thin metal, usually sheet iron and steel, difiiculty is experienced in the operation of uniting with a continuous seam and by electric heat and pressure the marginal portions of a metal sheet or the edge portions of twoadjacent sheets.

one cause of the difficulty is the variable resistance to the flow of the electric currentthrough the marginal overlapping portions, which variable resistance is brought about by a non-parallel condition of said mar- !ginal portions so that when brought together thereis more of an overlap at one side portion than at the opposite side portion of the sheet or sheets. This condition is encountered in electrically welding the fiat sheets of commerce, the edge portions of which frequently are more or. less rough, but such condition is observable, more particularly, in electrically welding the marginal portions of a metal sheet which is bent to assume a hollow cross sectional form, as in the manufacture of cylindrical objects,like pipe. Experience shows that in bending a relatively wide sheet to a cylindrical form, the marginal portions of the sheet are unequally lapped, notwithstanding the fact that said marginal portions may have been out true prior to the bending operation; and when the electrical current is applied, such inequality in the lap results in a variable resistance to the flow of the heating current, frequently resulting in an imperfectly welded seam.

According to one part of this invention, the sheet or sheets are first preliminarily positioned in the work holders, the marginal portions are trimmed to bring them into parallelism, the marginal portions are then brought into overlapping relation so as to attain. uniformity in the extent or degree of the overlap throughout the width of the sheet or sheets, and electric heat is applied in conjunction with pressure to secure the continuous seam by which the marginal portions are welded together in a perfect manner. i

The mechanism for carrying out the operations herein briefly outlined embodies a plurality of work holders adapted for retaining the marginal portions of a single sheet or the corresponding portions of a plurality of sheets, one of said work holders being movable relatively to the other whereby the marginal portion confined in said movable work holder is brought into a definite overlapping relation to the other marginal portion.

In the machine disclosed herein, two pressure and current carrying electrodes are employed, both of which may be movable in a definite path relatively to the work, as disclosed in my prior application Serial No. M5511; but it is preferred inthe machine of this application to employ one stationary electrode and a rotatable electrode movable ina definite relation to the stationary electrode, whereby the marginal portion of the metal retained in the work holders are adapted to be positioned across the stationary electrode and in the proper overlapping order one to the other so that when traversing movement is imparted to the rotatable electrode the overlapped metal affords resistance uniformly throughout the width of the sheet to the flow of the electrical current from one electrode tothe other and through such overlapped mar gins, the traversing movement of the rotatable electrode feeding current progressively to the overlapped margins and applying the requisite pressure to the metal rendered plastic by the heating efi'eet of the' current so as to. secure the desired uniformity in the seam by which the marginal portions ment is imparted to the traveler or carriage by the operation of a screw and a nut, the I latter being guided by a suitable traekwvay and being connected operatively by a thrust bar with said traveler or carriage, With as said electrode begins its traversing movement in one direction and is thereby brought into contact with the material, the automatic switch is actuated to establish the flow of current during the welding operation, upon the completion of which said switch is again actuated to cut off the flow of current to the electrodes whereby no current flows through the electrodes upon the return traversing movement of the rotatable electrode to its initial position.

The relative positions of the work to the stationary electrode is determined primarily by gage mechanism, the latter being shiftable into operative relation to said stationary electrode for the purpose of initially bringing the marginal portions of the metal into proper relation to each other, said gage mechanism being shiftable out of position so as to be out of the path of the rotatable electrode and free from electrical contact with either electrode during this welding operation. It is preferred to employ a gage member mounted-by sliding movement in a hinged carrier, the same being swung on a horizontal axis so as to drop down out of the way after it shall have been used to determine the relation of both marginal portions of the work within the respective work holders.

A salient feature of this invention consists of means operating upon the marginal portions of the work for bringing the same into parallelism whereby in the subsequent operation prior to the application of welding heat and pressure said parallel marginal portions are uniformly lapped and afford resistance uniformly to the flow of the electrical heating current.

Said means for securing parallelism in the marginal portions of the work may be, and is preferably, embodied in the form of trimming mechanism adapted to be operated in embodied as a part of the gage mechanism so as to be shiftable therewith into and out of operative relation to the work holders upon thin metal, embodying this invention,

the welding mechanism being shown in the initial position.

Fig. 2 is a front elevation thereof.

Fig. 3 is a top plan view of" part of the machine illustrating the automatic driving means and an automatic current cut-out adapted to control the flow of current to the weldingmechanism.

Fig. 4 isa plan view, partly in horizontalsection, illustrating a plurality of workholders and a Work gage which is shiftable into and out of the path of the material to be operated upon by the welding mechanism.

Fig. 5 is a vertical section through a part of the machine and the work gage mechanism, the movable element of the-work gage being shown in operative position with respect to the stationary electrode.

Fig. 6 is a cross section through the gage mechanism and the stationary electrode shown in Fig. 5, illustrating the gage in the operation of determining the initial positions of the marginal portions of the work.

Fig. 7 is a side elevation, partly in vertical section, illustrating a preferred embodiment of the invention, wherein a duplex trimming mechanismis employed forthe purpose of cutting the marginal portions of the metal along the edges thereof in a manner to bring said edges into parallelism prior to the action of the welding mechanism thereon, the

dotted lines illustrating the. out-of-service position of the work-gaging mechanism and the work-trimming mechanism.

Fig. 8 is a plan view of the work-gaging mechanism and the work-trim ning mechanism shown in Fig. 7 the welding mechanism except the stationary electrode being omitted.

Fig. 9 is a cross section on the line 9.9 of Fig. 8,'illustrating the gaging mechanism and the trimming mechanism in position for operation upon the marginal portions of the work so as to bring the resulting edges of said marginal portions into parallelism prior to the operation of lapping the trimmed edges and prior, also, to the welding operation by which a continuous seam is obtained for joining said marginal portions of the metal in a satisfactory manner.

Fig. 10 is a detail sectional view of one form of spring pressure mechanism mounted on the reciprocating carriage for securing the required mechanical pressure of the roller electrode upon the material under treatment.

as to rotate the feed screw in one direction or the other whereby the electrode-supporting carriage may be reciprocated by poweroperated'mechanism.

The welding mechanism embodies a plurality of electrodes A, B which cooperate in applying electrical heat and mechanical pressure to the-thin pieces of material composing the work, said electrodes being movable relatively one to the other, and at least one of said electrodes being a roller adapted to traverse the lapping marginal portions of the material in order to produce a continuous seam or weld, whereby said marginal portions are united in a way to produce'a seam or joint integral with the metal, and said seam or weld is rolled by mechanical pressure acting upon the plastic metal to reduce the seam or weld substantially to the thickness of the individual pieces composing the work, thus eliminating rough or irregular surfaces at the seam between the pieces of metal.

' In the form of welding mechanism shown in the drawings I have elected to illustrate the same in connection with flat metal sheets, the same being united in end to end order So as to produce along continuous mass of metal which may vary from one hundred to three hundred feet or more in length, but it will be distinctly understood that the invention is not restricted to operation upon fiat 'metal, for the reason that the principle of the invention may be utilized in the treatment of metal composed of a thin sheet bent into cylindrical, tubular, or other desired form in cross section, and the edge portions of which metal sheet are to be united by a continuous seam.

The electrode A is preferably a flat elongated bar adapted to be supported in a stationary position in the machine, whereas electrode B is a solid roller or diskmounted in a carriage for movement in a rectilinear path and into contact with stationary electrode A, but in this connection it is desired to state that the invention is not to be. re-

,stricted to a stationary electrode and a roller electrode movable into contact therewith, for the reason that the welding mechanism may embody a plurality of cooperating rolls, substantially as disclosed in my application Serial No. 94,554 to which reference has 'been made. The stationary electrode A consists of a single piece or bar composed of copper or other good electrical conduct-,

ing material, such 'bar being substantially rectangular 1n cross section, as shown in Figs. 2 and 6, and the top edges of said bar being beveled at a, thus producing a narrow tread surface (1, intermediate the beveled edges a. The width of the tread surface a is equal to or slightly exceeds the width of the resulting seam in the metal, whereas the bar A is equal in length at least to the width of the material to be operated upon. The bar A is seated in a recess 0 of a pillar C attached rigidly toan arm C extending forwardly from the frame I) of the machine, said electrode bar A be- -ing retained in position by a clamping plate 0 which is engaged by a bolt 0 secured in the arm C, whereby the electrode bar A is retained fixedly in a horizontal position, and said electrode may readily be dismounted from the supporting arm C when occasion demands.

The roller electrode B is composed of a mass of copper or other good electrical conducting material, the edge portions ofovhich are beveled at 7) so as to produce a tread surface b, the width of which is equal substantially to the width of the tread surface a of stationary electrode A, see Fig. 2. Said roller electrode is carried by an arbor I) which is mounted in any suitable way in bearings of a swinging arm I), said arm being forked or slotted as shown in Fig. 1 to permit the roller electrode to rotate freely within the slotted portion. The carrying arm D is supported for pivotal movement .on a spindle (Z mounted in depending lugs (Z of a carriage E. Said carriage is fitted snugly to the under side of an overhanging zontal position over stationary electrode A.

The arm F is provided at its lower edge with lateral flanges constituting a track or guideway' for the carriage E, the respective side portions of which are provided with upstanding flanges c which embrace the laterally extending flanges f, as shown in Fig. 2, whereby the carriage is fitted slidably to the under side of the arm F. Said carriage is provided with upstanding bolts f on which are loosely fitted wear plates f which are pressed forcibly into contact with the upper surfaces of the t ack flanges f by springs P which loosely encircle the bolts f, and the tension of which springs is adapted to be regulated by adjusting the nuts 7 on said bolts. The wear plates f and spring 7"? provide means for retaining the carriage E into close frictional contact with the under-surface of the arm F, thus-compensating for wear due to the frictional engagement of the moving part E with the stationary part F, but at the same time said carriage E is free to move in a rectilinear path along the guideway afforded by the overhanging arm F so aS to impart a traversmg movement to the roller electrode B.

Said roller electrode and the pivoted arm D are held normally in a raisedposition by a spring G, see Fig. 1, the respective end portions of which are attached to pivoted arm D and to depending lugs d of the carriage, but the required mechanical pressure from the roller electrode B to the material 7 under treatment is secured by plungers G, one of which is shown in detail in Fig. 10.-

Said plungers G are positioned at the respective sides of carriage E (see Fig. 2), and are fitted sli'dably in guides 9 provided on said carriage. The plungers are pressed downwardly by the action of'springs g incased within the guides g, and said plungers are in contact at their lower end portions with arms 9 which are rigid with the pivoted arm D. The plungers G and the spring G thus act in opposition to each other, as it were, in retaining the arm D and the roller electrode B normally in pre determined positions for said roller to have electrical and mechanical contact with the lapped marginal portions of the metal to be For imparting the traversing movementto carriage E and roller electrode B, I employ a feed screw I, a traveler J and a nut K, substantially as shown in Figs. 1 and 3.

Said traveler J is fitted for sliding move-.

ment 'in a horizontal path on guideway j forming a part of the machine frame D, and in order to connect the traveler J with carriage E, a bar or link J is used, the

same being housed or contained within a chambered part of machine frame D, as indicated in dotted lines in Fig. 1, and the respective end portions of said link or bar J are connected pi-votally with traveler J and carriage E. The traveler is provided with upstanding arms y" between which is fitted the nut K. Said nut is connected with the traveler J for a limited sliding movement between the upstanding arms j and, furthermore, the nut is provided with an axial threaded opening with which engages the threads of the feed screw I, whereby rotative movement of the feed screw imparts movement to the non-rotatable nut K, and thus the movementof thenut is communicated to the traveler J. The feed screw I is unitary with a drive-shaft I journaled insuitable bearings provided on the machine frame D, and upon a gear housing D the latter being fixedly attached to the rear part of the machine frame D. Upon this gearhousing is positioned a motor L, the shaft of which is provided with a gear I that meshes with agear Z on a shaft L, the latter extending within the gear housing D. .The shaft L drives a train of reversiillg I m on the motor driven shaft, and thus the. gears M M are normally driven in opposite directions to each other by the shaft L, but, said gears M M do not communicate motion to the shaft I or the feed screw 1, except when one or the other of said gears M M are" made fast with said shaft I. The operation of making the gears M or M fast with the shaftI is accomplished by a clutch N mounted on a shaft n in the gear housing D said clutch N being positioned between the gears M M and adapted to engage with clutch faces provided on said gears or to be retained in a neutral position intermediate said gears. The means for operating the clutch is controllable in a way by the traversing movement of the traveler J, but means are provided, also, for manually throwing the clutch into operative engagement with the gear M for the purpose of starting the machineinto operation. I

The clutch shaft 9t protrudes at one end beyond the gear housing, to which protruding end is secured a lever O, the upper part of which is expanded to form a cam-shaped head 0, the cam surfaces of which are oppositely inclined to each other, as shown in Fig. 1. The shipper lever O is adapted to be manually operated by a lever 10 mounted loosely on the clutch shaft n. The upper part of this lever 10 is provided with lugs 11, 12 positioned at the respective sides of the shipper lever O and adapted to engage therewith. The lower end of the lever 10 is formed with a toe-piece 13 engaged by a latch 14 pivoted on the machine frame D, and to this latch isconnected a link 15, the lower end of which is pivoted to a bellcrank 16, the depending arm of said.

bellcrank being pivoted to a rod 17 which is pressed in one direction by a spring 18,

said rod being pivoted to a foot-treadle 19 positioned within convenient reach of the operator. stationed at the front of the machine. With the latch 14 in engagement with the lever 10, the clutch is locked in a neutral position free from engagement with the gears M M, but when it is desired to set the machine into operation the attendant presses a treadle 19 and withdraws latch 14 from lever 10, whereupon a spring 20 presses a roller 21 forcibly against one cam surface of leverO, thereby turning the shaft 'feed screw is rotated in'one direction, so as to act on the nut K and impart traveling movement to the traveler J, 'whereby the thrust bar J is actuated to impart movement to the carriage E and traversing movement is thereby imparted to the roller electrode with respect to the stationary electrode.

The clutch is automatically disengaged from gear M as the roller electrode reaches the limit of its movement over the stationary electrode, and this actionis brought about by an automatic stop mechanism now to be described;

22 designates a horizontal bar positioned intheupper part of the machine and intermediate the gear housing D and the rigid arm F, one end of said horizontal bar being pivotedtoa rocker 23 supported on the machine frame.- The other end of this horizontal bar is linked'to a rockshaft 24 supported in a bracket 25 attached to the gear housing D said rockshaft being provided with a depending link 26, to the lower end of which is pivoted a bar 27, the other end i of which has a pin and slot connection 28 with the lever O. Said horizontal bar 22 carries two

stops

29, 30 which are adjustably fastened to said bar 22, and with these stops cooperates a pin 31 (indicated in dotted lines in Fig.- t) attached to one of the arms oftraveler J, said pin 31 being positioned for movement between the

stops

29, 30. As the traveler J moves forwardly under the action of the screw the pin 31 approaches the stop 20, and when the returnin traveler and the pin reach the limit of their forward movement, said pin strikes the stop 29 and imparts movement" to the bar 22, the latter operating to rock the shaft 24 and swing the link 26 in a direction to impart movement to the bar 27, the operation of which imparts rocking movement to the lever 0 so as-to turn the shaft 1 and thus.

shift 'thefclutch N from the -"gear M over to and into engagement with thegear M,

the result of which is to'reverse the dII'GC-V tion of rotation of the feedstg'ew I. The screw now acts'on the nut' K to move the .travelerJ in a" reverse direction, thus drawing the carriage E and the roller electrode B backwardly over the welded seam, such reverse movement taking place until the pin 31. strikes the other stop 30, whereupon the bar 22 and rockshaft 24, are operated to impart movement m a .revorse direction'to the 'bar 27, and thusfretilifnfithe lever O to a. position wherein-the clutch Nis free from engagement with. gears 'M orM,

stopping the operation of the -rnachine and the clutch ina. neutral position,

the lever 10. into {position to be engaged y the latch 14 .Twhich acts to lock a lug on which is mounted the roller 21,

as shown in Fig. 1, said lever 32 and the spring 20 being yieldable to the cam surfaces of the lever 0 when said lever is operated by manually depressing the treadle 19 or by the action of the

automatic stops

29 and 30.

Projecting forwardly from the machine frame are

brackets

33, 34 positioned at the respective sides of the arm C which carries the stationary electrode A. Bracket 33 carries or supports one of the two work holders, said work holder on the bracket 33 being. indicated in its entirety by the reference character P, whereas the other of the two work holders, Q, is carried by the bracket 34. Said work holder Q may be of any approved construction, but as shown hereinit is adapted for the reception of metal in sheet form. Said work holder Q embodies a base 9 and a pivoted clamp g, the latter being depressed upon the metal by the operation of a cam lever gflsee Fig. 2. The work holder Q is stationary with respect to electrode A. The other work holder P embodies a bed plate p,- a pivoted clamp p and a cam lever p similar in all respects to the corresponding parts of work holder Q, but the bed plate p of work holder P is shiftable with respect to the work holder Q for a purpose which will presently appear. Said work holder P is fitted for sliding movement within a flanged foundation plate 35 fixedly attached to thebracket 33. Cooperating with the sliding bed plate 10 is an eccentrlc 36, see dotted lines in Figs.- 2 and 4, the same being attached to a shaft 37 supported in a fixed bearing 38 of the foundation plate 35, and to the lower end of this shaft is attached an operating lever 39, whereby the cam may be manually rotated for the purpose of advancing the work holder P to- Ward the work holder Q in" order to position I the marginal portions of the metal in lapping relation over stationary electrode A.

It will be understood that the machine of this invention is adapted for operating upon sheets are to be positionedin lapping relation and into contact withthe stationary v electrode A so as-to be operated 'upon by the traversing electrode B. Subsequent to the introduction of the sheet or sheets within the work holders, the marginal portions of said sheet or sheets are initially positioned by gaging devices in accurate relation to the stationary electrode, and I will now proceed to describe one practical form of gage mechanism which may be used for the purpose mentioned.

On the front end of the machine, and below the stationary electrode is supported a horizontal arbor 40, the latter being fixedly attached to the

brackets

33, 34, and serving as a means for tying the same together, this function being performed, also, by the tie rod 41, see Fig. 2. Mounted loosely on the arbor is a carrier 42 constituting one element of the gage device, the other element of which gage device is a sliding bar 43.

The carrier 42 is provided with a guideway' '44 in which is slidably fitted the gage bar 43, the latter being provided on its outer end with a hand-grip45, see Fig. 5. The

. sliding gage member orbar 43 is provided on its under side with a groove 46, which grooved part of the gage bar is adapted to fit the beveled and track surfaces 0, a of.

electrode A. when the gage is in the operative position shown in Figs. 5 and 6. The gage is provided on its uppersurface with an upstanding shoulder 47, the latter being positioned intermediate two upper surfaces of the gage, which two surfaces are in different horizontal planes, see Fig. 6. The carrier is adapted to swing on a horizontal axis afforded by the arbor 40, so that the carrier may be dropped down to the out-of-service position shown in Fig. 2, but it is apparent that the carrier may be swung in an upward direction to assume the operative position illustrated in Fig. 5, in which operative position the carrier is retained by a latch 48, the same being pivoted on the carrier and controlled by a spring 49, the end of the latch 48 being adapted for locking engagement with a keeper plate 50 fixed to the bracket 33 and positioned in the path of the latch 48 when the carrieris swung upwardly into the operative position.

In using the gage mechanism the carrier is swung on the arbor 40 to the raised position of Fig. 5, the latch 48 snapping into engagement with the keeper plate 50. The operator now presses the gage bar 43 inwardly so as to slide it lengthwise of. the carrier 42, which inward sliding movement of the gage bar brings the grooved portion 46 into contact with the top portion of electrode A. Thegage-bar is thus positioned intermediate the inner approximate ends of work holders P Q,-whereby the stop shoulder 47 of the gage bar is in the path of the marginal portions of the 'materi'al. With the clamps'p q of work holders P Q, re-

spectively, in raised positions, the work can be adjusted within the holders so that the marginal-portions X X of the work are adapted to be positioned upon the two surfaces of the gage bar 43 and into contact with the stop shoulder 47, the gage bar and its shoulder thus serving to initially position the'marginal portions X X of the work in accurate relation to the electrode A and at a time when the roller electrode B is withdrawn from the path of the material, as shown in Figs l and 4. The operator should now manipulate levers p 9 in order that clamps p, 9 may grip the work and retain the same fixedly in position within the work holders whereupon the gage bar should be pulled outwardly and away from contact with the marginal portions of the material, so that the latch 48 may be released and the entire gage device dropped down into the out-of-service position of Fig. 2. The position of the marginal portions of the material-having been accurately determined, the next-step in the operation consists in bringing said marginal portions into lappinggcontact, and this is effected by moving the lever 39 to impart rotative movement to cam 36, the latter acting to advance the work holder P and the material X, so that the material X will lap the material X over the electrode A. The work is thus adapted .to be held firmly bythe two holders and to be accurately positionedwith respect to electrode A. It should be stated that prior to introducing the work into the machine and gripp ng said work by the holders P Q, the

margmal'portions of the material should be sandrblasted', as disclosed in my application Serial No. 89289, whereby the surface oxidation or scale is removed from the marginal portions of the work, which marginal portions are to be brought into lapping con- .tact and electrically welded by the application of electric heat so as to render the metal plastic, and by the application of-mechanical pressure to effect the continuous seam which unites said marginal portions of the material.

I will now proceed to describe the, trimming mechanism by which the adjacent marginal portions are adapted to be cut or trimmed on parallel lines subsequent to the mechanism is shiftable with the gage mechanism into and out of operative relation to the electrodeA and to the marginal portions of the material.

Referring now more particularly to Figs.

7, 8 and 9 of the drawings, the electrode A and the gage carrler 42 are similar to the devices heretofore described, but in this embodiment of the invention it is preferred to employ a gage bar 43 whichissomewhat wider than the gage bar 42, heretofore described and illustrated in Figs. 5 and 6. The

wide gage bar is provided'with a longitudisides of this bar arefitted the

blades

53, 54,

the same being bolted firmly'to the cutterhead. The blades'run'parallel of the cutterhead and they are adapted to shear past the edges of the slot 51 in the gage member, see Fig. 9. The cutterhead is forked at one end, as at 55, and it is pivotally mounted on lugs or bearings 56 extending upwardly from the gage member 43, for which purpose the forked end of the'cutterhead is attached to a horizontal rockshaft 57 Around this 'rockshaft is coiled a spring 58 which tends to normally lift the cutterhead in order to free the

blades

53, 54 from the slot 51 of the gage member, thus allowing the material X X to be readily introduced over the gage 43 and into contact with the stop 47 Suitable means are provided for manually operating the cutterhead 52, but as shown more particularly in Fig. 7, said means are treadle-operated by the following mechanism 1- An armv58 is attached rigidly to the rockshaft, the lower end of said arm being connected to a link, 59,- the other end of which link is pivoted to a rocker arm 60 fitted loosely on arbor 40, supported as heretofore described on the machine frame or upon the

brackets

33, 34 thereof. This rocker arm 60 is provided with a lug 62 which is positioned in cooperative relation to a lug 63 forming a part of an arm 64 which is fitted loosely on arbor. 40. To the free end of the arm 64 is'pivoted the upper end of rod65', the latter being impelled normally in an upward direction by a spring 66; I Said rod passes loosely through a guide 67, and thelower end of the rod is attached to the treadle 68. The trimming mechanism is thus attached to or mounted on the shiftable member 43 of the gage, and said trimming I mechanism is shiftable with the carrier 42 when the latter is moved into or out of the out-of-service position, the link 59 permite cutterhead 52 with the gage mechanism when the carrier 42 is swung on the horizontal axis afforded by the arbor 40.

It is apparent that the movement of the carrier 42 inan u'pward direction can take place freely,.for the reason that'the

arms

60, 64 and link 59 permit of such movement.

When elevated and held by the latch 48 the 1 carrier presents the gage member 43 into position for, movement over electrode .A, which movement is readily effected by the operator applying pressure to the hand-grip 45. The gage may thus slide over the elec-v trode, and in this operation the cutting mechanism is movable with the gage, but the spring 58 retains the pivoted cutterhead in the raised-position shown in so that the material X X 'can bemovedfi over and into contact with'the gage, whereby: the material will be positioned by the stop.

47 into proper relation to the electrode A. The operator now applies pressureLtofgthe treadle 68 so as to turn the arm 64 and its shoulder 63 into contact with the s'hoiilder 62 of the arm 60, whereby the arm 60 is rocked to impart movement to link 59 and;

arm 58 in a manner to depress the cutterhead 52 and cause the

knives

53, 54 to shear the marginal portions of the material X X,

as a result of which the adjacent edges of said marginal portions are brought into parallelism. Upon removing pressure from the treadle 68, the spring58 lifts the cutterhead clear of the gage, after which the member 43 is withdrawn, the latch 48.is released and the carrier and the trimming. mechanism are dropped to the outof-service positions. The material which is held in one work-holder, as P, is now manipulated to bring the trimmed edge of said material into lapping contact with the other trimmed edge of the material, and for this purpose it is only necessary to impart the required sliding movement to the work-holder P, the

extent of the sliding movement being dewhich are effective in removing rough edges from the material and operating to secure parallelism between the trimmed edges of the marginal portions X X, whereby the marginal portions are adapted to be overlapped to an equal extent throughout the width of the sheet or sheets of material, as a result of which the equally lapping portions of the material offer resistance uniformly to the flow of the welding current at all points in the traverse of electrode B relatively to the lapped margins of material.

The machine disclosed herein embodies a transformer positioned within a chambered part of the main frame D, wherebythe weight of said transformer is not imposed upon the movable part of the machine, such as the element which carries the movable electrode and which is one of the characteristic features of a prior application Serlal No. 123,269, the title to which, and to the terminal connected with the carriage for the movable electrode B, whereas the other terminal includes the stationary electrode A, whereby current is supplied to the electrodes A,-B for the purpose of rendering plastic the metal which it is desired to weld by a continuous seam. The electrical equipment shown includes a controlling, solenoid 7 2 and switches" 7 3, 74 actuated substantially in the manner disclosed insaid application Serial No. 123,269. The flow of current to the electrodes is dependent upon the contact of roller electrode B with the, lapped portions 1 of the metal, and upon the operation of a cut-out S shown in Fig. 1. This cut-out comprises a stationary contact 75 and a movable contact 76, the latter being on a vibratory arm 7 7 under the control of a spring 78. Cooperating with the vibratory arm is a detent 79 which is normally in engagement with a movable detent 81 carried by a vibratory arm 82 under the control of a spring 83, and adapted to be arrested in a normal position by the stop 84. The vibratory arm 82 is in the form of a bellcrank, one end of which is engaged by a latch 85, which cooperates with stops-86, 87 carried on a shiftable bar 88. One end of this shiftable bar 89 of the carrier E, said arm extending upwardly through a slot in the overhanging rigid arm F, but the other end of the horizontal bar 88 is pivoted to the forward arm 9' of traveler J. In the normal position of the cut-out the spring '83 holds the detent 81 into contact with the detent 79, thus locking the vibratory arm 77 for the contact 76 to be free from the contact 75, and from these

contacts

75, 76 run conductors 90, 91 leading to the solenoid and the switches so as to prevent the flow of current to the electrodes A B in the normal position of the mechanism. Asthe electrode B makes contact with the lapped marginal portions of A the metal, the stop 86 is carried by the forward movement of the traveler-away from the latch 85, so that the vibratory arm 77 will be operated to move the contact 76 into electrical engagement with contact 75, and thus establish the flow of current to electrodes A B, the effect of which is to-render plastic the metal under treatment, and as the electrode B traverses the metal and the electrode A, the metal is pressed together and welded to produce the continuous seam. By the time that the electrode B completes its forward movement, the stop 87 actuates the arm 82 so as to restore the detent into contact with the member 79 and separate the contact 76 from contact 75, breaking the circuit on the return movement of the electrode B to its initial position.

It is thought that the operation of the invention will be understood from the foregoing description, but it may be summarized are sand-blasted, as heretofore described, in

order to remove the surface oxidation and scale. When operating upon flat metal sheets, the marginal portion of one sheetis introduced into holder P, .and a marginal portion of another sheet is introduced into holder Q, but should the mechanism be desired for operation upon tubular sheets, the respective edge portions thereof are introduced into the two holders P Q. The gage is used to initially determine the relative positions of the marginal portions of the metal, and the trimming mechanism is operated to shear off the adjacent edges of the margins, thereby removing any rough edges and bringing said edges into parallelism, after which the gage and trimming mechanism are moved to the out-of-service position. The holder P is now moved toward the holder Q, until the trimmed edges are in contact, and as the edges are parallel it follows that the marginal portions are lapped to a uniform extent throughout the width of the sheet or sheets, whereby said marginal portions ofi'er resistance uniformly to the flow'of the welding current. The operator presses upon treadle 19 and the motor actuates' to impart the traversing movement to roller electrode B, current being supplied to said electrode B and the electrode A to render the metal plastic. The roller electrode travels between the work holders and over electrode A to effect the welding progressively, for the reason that the metal is rcn' dered plastic as the roller passes along said metal, and said roller cooperates with electrode A in applying the pressure required to effect the union of the marginal portions of the metal, as a result of which a continuous seam is produced which affords a satisfactory union between the marginal portions, the application of pressure rolling the metal along the seam down to the gage of the individual pieces composing the sheets, in case two sheets are Welded in the manner described. As the roller electrode reaches the limit of its movement, the cut-out operates to preclude the flow of current, and the driving mechanism then becomes effective in imparting reverse motion to the carriage and to the roller electrode so as to return said parts to their initial positions.

It should be mentioned that provision is made for supplying a cooling medium to the pivoted arm D which carries the roller electrode and tothe arm C, which supports the stationary electrode, for which purpose water circulating pipes 92 are "attached to the proper parts, as clearly shown in Figs. 1 and 4.

- The machine disclosed herein produces continuous seams or welds between the metal, and operates rapidly upon the metal so as to attain large capacity for the performance of the required work. By removing the transformer from the carriage of the roller electrode, the weight of the moving parts is minimized, whereby the means or imparting reciprocating .IIlOtlO'IlftO thefar riage can be and is speedediupto'secure-the desired? rapidity of op'eration, all of the required operations being automatic except those necessary to start the machine into service and to introduce and remove the material.

It will be noted that the feed nut isheld from rotative movement by the traveler and that said feed nut has a limited lostmotion with respect to the traveler. This is desirable in overcoming the inertia of the moving parts at the periods of time when the direction of rotation of the feed screwis reversed so as to effect/the back and forth movements of the electrode-supporting carriage.

The improvement in theart of electric welding thin metal herein shown anddescribed is not claimed herein for the reason that such improvement in the art forms the subject matter of a divisional, application filed March 31, 1917, Serial No. 158,814.

Having thus fully described the invention, what I claim as new, and desire-to secure by Letters Patent is 1. In an electric welder, the combination with a plurality of work holders, of means for trimming the marginal portions of thin metal to secure parallelism in the resulting edges, said trimming means being operable subsequently to the operation of positioning the thin metal in the work-holders, means for effecting a relative movement between said marglnal portions whereby they are positioned in lapping contact, and means for electrically welding the marginal portions of said thin metal.

2. In an electric welder, the, combination with a plurality of work holders, of means for trimming the marginal portions of thin metal to secure parallelism in theresulting edges, said trimming means being operable subsequently to the operation of positioning the thin metal in the work-holders, and means fo moving one work holder relatively to the other whereby subsequent to the trimming operation the-marginal portions ofthe work are positioned into lapping contact, and means for electrically welding the marginal portions of said thin metal.

3. In an electricwelder, the combination with a plurality of work holders, of means for determining the initial positions of the marginal portions of thin metal, means for trimming said marginal portions and thereby bring the resulting edges into parallelism, said trnnming means being operable subsequently to the operation of positioning the thin metal in the work-holders, and means for effecting a relative movement between the marginal portions subsequent to the trimming operation whereby the trimmed marginal portions are positioned into lapping contact, and means for electrically welding the marginal portions of said thin metal.

4:. In an electric welder, the combination witha plurality of work holders, of means for determiningthe initial positions of the marginal portionsof thin metal, means for trimming said marginal portions and thereby bring the resulting edges into parallelism, and means for moving one work holder relatively to the other for a predetermined distance and subsequently tothe trimming operation whereby the trimmed marginal portions. are positioned into uniform lapping contact. 4

5. In an electric welder, the combination with a plurality of work holders, of workgaging means for determining the initial positions ofthe marginal portions of thin metal, welding mechanism, said work-gaging means being shiftable relatively to said welding mechanism, and work trimming means operable upon said marginal portions for'bringing them into parallelism prior to the action of the welding mechanism 6. In an electric welder, the combination with a plurality of work holders, of means for initially determining the position of the work with reference to the respective work holders, means operable simultaneously upon the contiguous "marginal portions of the work to trim the same and thereby secure parallelism between said marginal portions, and welding means for securing the desired union between said trimmed marginal portions.

7. In an electric welder, the combination with a plurality of work holders, of means for initially determining the position of the work with reference to the respective work holders, means operable upon the marginal portions of the work subsequently to the initial positioning thereof for trimming said marginal portions and thereby secure parallelism between the edges of said marginal portions, means for efiecting lapping contact between the trimmed marginal portions, and welding mechanism for securing the desired union between said marginal portions. n

8. In an electric welder, thecombination with a plurality of work holders for retaining the marginal portions of the work in definite relation to each other, gaging means tions of said marginal portions, means operable subsequently to the initial positioning of said marginal portions for securing parallelism between the edges thereof, means for effecting lapping contact between said marginal portions, and welding mechanism whereby the desired union is secured between the marginal portions of the material.

9. In an electric welder, the combination with a plurality of work holders for retaining the marginal portions of the work in definite relation to each other, of trimming means operable upon themarginal portions of the work for securing parallelism between the edges thereof, means for efl'ecting lapping contact between the trimmed marginal portions of the work, and welding means for securing the desired union between said trimmed marginal portions.

10. In an electric welder, the combination with a plurality of work holders for retaining the marginal portions of the work in definite relation to each other, of gaging means for initially determining the relative positions of the marginal portions, said gaging means being shiftable into and-out of operative position with reference to the work holders, trimming means operable upon the mar 'nal portions of the work for securing para lelism between the edges thereof, said trimming means being shiftable in unison with the gaging means, means for effecting lapping contact between the trimmed marginal portions, and welding means for securing the desired union between said lapped marginal portions of the work.

11. In an electric welder, the combination with a plurality of work holders for. retaining the marginal portions of the work in definite relation to each other, of gaging means for initially determining the relative positions of the marginal portions, said gaging means being shiftable into and out of operative position with reference to the work holders, trimming means operable upon the marginal portions'of the work for securing parallelism between the edges thereof, said trimming means being carried by the gaging means and shiftable therewith into and out of operative relation to the work, means for effecting lapping con" tact between the marginal portions, and atraversing electrical welding device movable in a definite path with respect to the lapped marginal portions for uniting the same with a continuous seam.

12. In a electric welder, the combinationv tive positions of the marginal portions, said gaging means being shiftaBle into and out of operative position with reference to the Work holders, trimming means operable upon the marginal portions of the work for securing parallelism between the edges thereof, said trimming means beingshiftable in unison with the gaging means, means for moving one work holder relatively tothe other for effecting lapping contact between said trimmed marginal portions, and

a traversing welding device operable for i applying electrical heat and mechanical pressure to the lappedmarginal portions and unite the same by a continuous seam.

13. In an electric welder, the combina- 7 tion of a roller electrode, a relatively sta tionary electrode cooperating, with said roller electrode, a carriage on which the roller electrode is mounted, a feed screw, a

traveler separate from said'carriage, a feed the other guideway, means connecting the traveler and the carriage for impa ting movement to the latter from the former, a plurality of cooperating electrodes one of which is supported by the carriage,ea feed 7 "nut movable with the traveler, a feed screw,

and a reversible driving mechanism for'imparting rotative movement to said Jfeed screw. v v I 15. In an electric welder, a plurality of. separate guideways, a carriage slidableilon one of said guideways, a traveler slidable on the other guideway', means connecting the traveler and the carriage for imparting movement to the latter from the former, a plurality of cooperating electrodes one of which is supportedby the carriage,vpre$ure means for efi'ecting a relativemovement -.between said electrodes whereby mechanical pressure is applied to the metal under treatment during a traversing movement of the carriage, and meansracting upon the traveler for imparting reciprocating movement to said traveler and carriage.

16. In anelectric welder, aplurality of separate guideways, a carriage slidable on one of said guideways, a-.traveler slidable on the other guideway, ;neans connecting the traveler and the carriage for'imparting movement to the latterv from the former, a plurality of cooperating electrodes one of which is supported by the carriage, a feed nut held from rotative movement by the traveler and movable therewith, a-feed screw,

a reversible driving mechanism for impartmg rotatlve movement to sald feed screw,

, and means operable-by the movement of the traveler for controlling the reversible driving mechanism.

17. In an electric welder, the combination with a carriage, and a plurality of electrodes at least one of which is supported limited lost motion relatively to the traveler,a feed screw, and means for imparts ing rotative movement to the feed screw.

18. In an electric welder,the combination with a trackway, of a carriage slidable relatively thereto, a spring-actuated arm pivoted to said carriage and movable therewith, a plurality of electrodes at least one of which is mounted in said arm and held thereby 'in cooperative relation to the other electrode, and means for imparting reciprocating movement to said carriage.

19. In an electric welder, the combination with a trackway, of a carriage slidable relatively thereto, an arm pivoted to said carriage, pressure'means mounted on the carriage and cooperating with the arm for yieldably forcing the sa me in one direction, a stationary electrode positioned parallel to the path of .the carriage, a roller elec trode mounted in the pivoted arm and adapted to be yieldablypresented thereby into cooperative relation to the stationary electrode, and means for imparting traversing movement to said carriage.

20. In an electric welder, the combination with a relatively stationary electrode, and a trackway positioned in parallel relation thereto, of a carriage in under running contact with said trackway, means for retaining said carriage in sliding contact with 'said trackway, means for imparting reciprocating movement to said carriage, an arm pivoted to the carriage and movable therewith, a roller electrode mounted for rotative movement in said arm and movable with the carriage so as to partake of a traversing movement relatively to the stationary electrode, and pressure means operatively related to said pivoted arm whereby mechanical pressure is applied by the 00- operating electrodes to the metal under treatment during the traversing movement imparted to the roller electrode.

21. In an electric welder, the combination with a relatively stationary electrode, of a trackway in overhanging relation thereto, a carriage slidably fitted, to said trackway, an, arm pivoted to said carnage, said arm be ng forked, a roller electrode positioned within the forked portion of the arm and mounted in the arm for rotation-freely therein, pressure means carried by the: carriage and cooperating with said arm for pressing the roller electrode toward the stationary electrode, and means for imparting traversing movement to said carriage.

22. In an electric welder, the combination with a relatively stationary anvil electrode, and a trackway adjacent thereto, of a a rriage fittedto said trackway for sliding movement thereon, a movable member mounted on the carriage, a roller electrode supported by said movable member and movable therewith relatively to said carriage, pressure means mounted on the -arriage and cooperating with the movable member for effecting the required pressure upon the material under treatment between said electrodes whereby the material is rolled to gage, and means for imparting a traversing movement to said carriage.

23. In an electric welder, the combination with a plurality of work holders, and welding mechanism, of a gage mechanism shiftable into and out of cotiperative. relation to said work holders, said gage mechanism embodying two movable'members one ofwhieh is adapted to be positioned between said work holders.

24:. In an electric welder, the combination with a plurality of work holders, and \veld ing mechanism, of a gage mechanism embodying a swinging member and a slidable member carried by the swinging member, said slidable member being adapted to be interposed intermediate said work holders.

25. In an electric welder, the combination with a. plurality of work holders, and welding mechanism, of a gage carrier mounted for movement into an out of service relation to the welding mechanism, and a gage member connected with the gage carrier for movement therewith, said gage member being movable relatively to the gage carrier for interposition intermediate the work holders.

26. In an electric welder, the combination with aplurality of work holders, and welding mechanism, of a gage carrier mounted for movement into an out ofservice relation to the welding mechanism, means for locking the gage carrier in operative position, and a gage member mounted on the. gage carrier and movable into position intermediate said work holders.

27. In an electric welder, the-combination with a stationary electrode, and a plurality of work holders, of a gage member movable into position over said stationary electrode and intermediate the work holders.

28. In an electric welder, the combination with a'stationary electrode, and a plurality of work holders, of a gage member movable into position over said stationary electrode and intermediate the work holders, said gage tioned in the path of the marginal portions of the'work adapted to be held in said work holders and operating to initially determine the relative positions of said marginal portions.

- gina l portions of the material to be united.

30. In an electric welder, the combination with a stationary electrode, and a plurality of work holders, of a gage member movable into position over said stationary electrode and intermediate the work holders, said gage member beingprovided with exposed surfaces with which are adapted to contact the marginal portions of the material to be welded and provided also with a stop member positioned intermediate said exposed surfaces so as to have contact edge wise with said marginal portions.

31. In an electric welder, the combination with a stationary electrode, and a plurality of work holders, of a gage carrier hinged.

for movement on a horizontal axis, and a gage member slidably connected with said gage carrier, said gage member being movable over the electrode and to a positlon intermediate said work holders.

32. In anelectric welder, the combination with a stationary electrode, and a plurality of work holders, of a movable gage carrier, and a slidable gage member sup-. ported by the gage carrier,-- said gage mem ber-being movable into contact ,with said electrode and toa position intermediate the work holders.

7 33. .I'n an electric welder, the combination witha stationary electrode, and a plurality'of work holders, of a gage carrier the axisofmovement of which is in a difierent plane from the surface of the electrode, and

' E-and movable" therewith, said Bo b eing' movable with respect to the gage car a gage member supported in the gage carrier age member QJr-ier] and to an operative position intermejdidtef'fsaid; work 1 holders.

"34. In an electricfwelder, the combination t i n ryelectrode, and a P Q holders, f gage arrier hinged I .for movement on a horizontal axis, and a gage member connected to-said carrier for sliding movement with reference thereto,

said gage member being movable into contact with-said electrode and to lposition intermediate' said Work'hol ders- I 35% In an 'electric'welder, the combination witha stationary electrode, and a plurality of work holders, of a gage carrier hinged fol movement on a horizontal axis, a latch for retaining the gage carrier in a fixed relation to the work holders, and a gage member slidable upon the gage carrier and mov- 36. In an electric Welder, the combination with a stationary electrode and a plurality of work holders, of a gage carrier movable relatively to said work holders, and a gage member supported by the carrier and movable to a position intermediate the work holders, said gage carrier being provided with two exposed surfaces in different levels and upon which the marginal portions of the material are adapted to rest.

37. In an electric welder, the combination with a stationary electrode and a plurality of work holders, of a' gage carrier movable relatively to said work holders, a gage member supported by the carrier and movable to a position intermediate the work holders, said gage carrier being provided with two exposed surfaces in different levels and upon which the marginal portions of the material are adapted to rest, and means for moving one work holder relatively to the other, whereby upon the withdrawal of the gage member the marginal portion in the movable work holder is positioned into lapping contact with the marginal portion in the other work holder. 1

38. In an electric Welder, the combination with a stationary electrode and a plurality of work holders, of a gage carrier movable relatively to said work holders, and a gage member supported by the carrier and movable relatively thereto so as to assume an operative position intermediate the work holders, said gage member being provided member movable into an operative position mtermediate said work holders, a trimmingv mechanism carried by said gage member,

means 'for operating said trimming mechanism independently of the movement of the gage member whereby the trimming mechanism is effective in bringing the edges of the marginal portions of the material into parallelism-prior to the welding operation, and means for weldin the trimmed edges of said marginal portions.

40. In an electric welder, the combination with a plurality of work holders, of a gage member movable into an operative position intermediate said work holders, and a worktrimming mechanism carried by said gage member, said work-trimming mechanism being operable independently of its movement with the gage member. a,

*1. In an electric welder, the combination able into contact with said electrode and to a position intermediate the work holders.

42. In an electric welder, the combination with a plurality of work holders, of a gage I member movable into an operative position intermediate sald work holders, a cutterhead v mounted upon the gage member, a'plurality of cutters attached to the'cutterhead, means for liftingthe cutterhead relatively to; the gage member so as to permlt the marginal portions of the material to be positioned by' the gage member, and means for operating said cutterhead.

43. In an electric welder, the combination with an anvil electrode, and a plurality of work holders, of aslotted gage member movable into contact with said anvil electrode and to an' operative position intermediate the work holders, a cutterhead attached to the gage member and movable therewith, means for retaining the cutterhead in such relation to the gage member as to permit the free adjustment of the work into contact with said gage member, cutters on the cutterhead adapted to shearthe metal, and means for operating the cutterhead.

44.- In an electric welder, the combination with a plurality of Work holders, of a gage carrier movable relatively to the work holders, a gage member supported by the carrier and movable with respect to the work holders, cutting mechanism supported by the gage member and movable with said gage member and the carrier, and operating means for imparting movement to said cutting mechanism.

45. In an electric welder, the combination with a plurality of work holders, of a gage carrier movable relatively to the work holders, a gage member supported by the carrier and movable with respect to the work holders, cutting mechanism supported by the gage member and movable with said gage member and the carrier, and operating means effective in imparting movement to said cutterhead when the gage member is in operative position with reference to the work holders, said operating meansbeing shiftable with the cutterhead when the gage carrier is moved into an out-of-service position.

46. In an electric welder, the combination with a plurality of work holders, of a gage carrier movable relatively to the work hold ers, a gage member supported by the carrier and movable with respect to the work holders, cutting mechanism pivoted to said gage member, and treadle-operated means for imparting movement to said cutting mechanism, said treadle operated means including connections whereby free movement of the gage carrier is assured when shifting it to and from anoperative position.

47. In an electric welder, the combination with a stationary electrode, and a traveling carriage, of a roller electrode supported by the carriage and movable into cooperative relation to said stationary electrode, means for feeding current to said electrodes, and means responsive to the movement of the carriage for controlling the How of current to the electrodes during the traversing movement of the roller electrode in one direction and for cutting off the fio'wof current as the roller electrode travels in the opposite direc- SPENCER O. GARY.