A. H‘ LLOYD. . 1,398,731. Patented Nov. 29, 1921. 2 SHEETS SHEET 1 A. H. LLOYD- ' I LATHE. _ APYPLHIJAITION FILED MAY 5. 1926. ',398,731. Patented Nov. 29,1921. 2 sums-sneer 2._

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PET? 41.4%.- AT ORNEY " Unite m s ARTHUR HAROLD LLOYD, or" COVENTRY, ENGLAND._ LATHE. Lsesnsr. Speci?cation of Letters Patent. Patented Nov. 29, 1921. Application ?led May 5, 1920. vSerialNo. 378,952. To all 107mm it may concern: ut'acture ot' boilerlstaysis shownin the ac ' Be it known that. I, ARTHUR HAROLD companying drawings, in .which-_ LLOYD, a subject of the King of England, re~ . Figure l is a plan view, and , siding at Coventry, in the county of ‘Var Fig. 2 is an end view with the part on the wick, England, have invented certain new left of the line 2-2 in Fig. 1 removed. .60 and useful Improvements in , of Like letters indicate like parts throughout which the following is a speci?cation. the drawings. . ' This invention relates to lathes 'or like The saddle of the lathe is indicated at A; machine tools upon which are employed self the cross slide at B; the gripping the 10 opening die-heads, and it has for its princi stock in the hollow at C; the turret .65 pal object to provide an improved method of at D; and the self-opening die-head carried controlling the operative connection estab by it at E. A leader orlead- F which lished between the die-head and the lead is interchangeable with others for use with screw, so that thereby the time required for the lathe in the known manner has a gap or 15 certain kinds of work is substan equivalent interruption or a termination of tially reduced, thus resulting in a corre its thread at‘ F2, at a position adapted to spondingly increased output with a conse cause complete disengagement of the lead quent reduction invmanufacturing costs. screw or saddle nutat the completion of the The kind of work to which the invention threading operation. is especially applicable is that in which a At the back of. the slide B is, an inverted gap separates two similarly-pitched thread tool B2 for the reduced part G2 sit ed portions 01“ a member upon which the uated-between the threaded parts G3 of the relative dispostion of the threads upon the stay G; and on the front ot the?slide is a two parts must be such that they are in heli parting-cit tool B? for the ?nal operation on 25 cal register, with one another. It will be the stay. 1 . ' 80 evident therefore’ that when such threaded Upon the cross slide B is mounted a block parts are produced in a turret or like lathe H whose position is adjustable lengthwise the ordinary self-feeding action of the die and crosswise of the lathe bed. This block head cannot be employed owing to the gap carries a plunger H2 which is, by the agency between the two portions of the threads on of a spring Ht, resiliently thrust outward .85 the stay, and the present invention therefore for a limited distance toward the longitudi embodies certain features, which besides pro nal center line of the lathe. The nose H3 of viding tor the automatic operative connec-. the plunger is slightly beveled on its verti tion 01': the die-head with the lead screw, also cally disposed sides tov facilitate its engage 35 insure sub-sequent automatic disconnection ment with a notch J2 in a- member J carried 90 therefrom and the simultaneous opening of by the housing of the self-opening die-head the die-head when the threading operation is it‘ mounted in the turret‘ D. As usual the completed. ' turret is carried upon a slide adapted to. be According to this invention, in a- lathe or moved along the bed of the machine. , 40 like tool having a’saddle and lead screw, In machining a boiler stay of the kind 95 there are provided in combination, a resili employed around-?reboxes and the like, and ently acting bolt or plunger (preferably having a gap between its threaded'parts, the carried by the saddle) adapted at a predeten stock is fed through the hollow- lathe-man mined point inthe travel of the saddle to en drel in the known manner,'and the ?rst op 45 gage the turret slide, or other member carry eration is that of torming'the reduced por 100 ing the die-head, so that the latter travels tion G2 constituting the gap between the with the saddle; and a gap or a like inter threaded. parts G3 of the stay G, by means ruption in‘ the lead screw, which gap is of the tool B2 on the back part of the cross adapted, at the completion of the threading slide B. lVhen this operation'is completed, 50 process to disengage the saddle-nut and thus the self-opening die-head E mounted upon 105 automatically to bring the saddle to rest, the turret Dis brought‘ into position at the the die-head being opened simultaneously free end of the stay. The saddle A is then by the known means. ' adjusted lengthwise along the lathe-bed so The manner or" carrying out the invention that the nose H3 of the plunger H2, which, 55 upon a turret lathe as arranged for the man under the action of its spring H4, is adapted 110 2 1,398,731

to move radially inward toward the rota carrying out this kind of threading opera 65 tional axis of the lathe, is disposed so that, tion in such manner that both the threaded relatively to the direction of the saddle parts G3 are in helical register with one movement, it points somewhat to the rear of another, while by the provision of the gap the notch J2 in the member J upon the die F2 in the lead screw F no danger of injury head housing when the die-head is in posi to the lathe or to the work arises in the op 70 tion to engage the end of the stay G. I The eration of opening the die-head and it will usual saddle-nut A2 is then engaged with also be seen that the whole of the machining, the lead screw F and the cross slide B is fed operation can be carried out with cons1der- . 10 inwardly. During this in~movement of the able rapidity and with a minimum of wasted cross slide the plunger H2, by coming into time. 75 contact with the rear side wall of the notch It will be evident that the foregoing com J2 in the member J, is forced back into the bination of parts can equally well bepro block H against its spring loading. As the vided either upon a turret lathe, in'which 15 saddle A commences to move, carrying with the movement of engagement of the saddle it the plunger Hz, the nose H3 of the latter nut also acts to feed inwardly the cross slide so’ comes into register with the notch J2 and is thereon, or upon an ordinary screw-cutting thrust into it by means of the spring H4 so lathe in which the action involves two dis that the die-head E is thus operatively con tinct operations. 20 nected to the saddle A and thereafter is ‘W hat I claim as my invention and desire moved along with it by the lead screw F at to secure by Letters Patent of the United 85 the appropriate rate of feed. ‘ States of America is :— The plunger block H carrying the plunger 1. In a lathe, a saddle, a self-opening die H2 is mounted on the front of the cross slide head carriedthereon, a saddle-nut carried 25 of the lathe and thus the block and the plun by said saddle, and a lead screw adapted to ger with it can be moved inward by the ordi be engaged ‘by said saddle-nut, and having a 90 nary screw transverse feed. In some makes gap which interrupts the threads formed of capstan lathe the cross slide is geared up upon it, thereby to automatically disengage to the- lead screw mechanism in such a man the saddle nut as it arrives in the gap. 30 ner that when the usual half nut is engaged 2. In a lathe, a main saddle, a saddle-nut with the screw an inward movement of the carried by said saddle, a lead screw adapted 95 cross slide amounting to about 3;” takes to be engaged by said saddle~nut and having place, effecting the engagement of the plun a gap which interrupts the threads formed ger with the notched member J. This well upon it thereby to automatically disengage 35 known construction, however, forms no part the saddle nut as it arrives in the gap, a sec~ of my invention. ondary saddle distinct from the ?rst saddle, 100 As soon as the die-head E completes the a self-opening die-head carried upon said ?rst threaded part G3 of the stay G and secondary saddle, and means adapted auto arrives at the reduced portion G2, the lathe matically at a pre-determined point in the 40 is speeded up in any known or convenient travel of the main saddle to establish a trac_ manner either by hand-controlled means or tive engagement of said main saddle with 105 automatically, until the gap portion G2 has said secondary saddle. I been traversed by the die-head, so that no‘ 3. In a lathe, a main saddle, a saddle-nut, time may be wasted in this movement. Just carried by said saddle, a lead screw adapted 45 before starting to cut the second part G3 of to be engaged by said sa ddle-nut and havin the thread, the speed of the lathe is reduced a gap which interrupts the threads forme 110 to the normal and the operation of threading upon it thereby to automatically disengage is then continued as in the ?rst case. Im the saddle nut as it arrives in the gap, a sec mediately, however, the predetermined ex ondary saddle distinct from the first saddle, 50 tent of this is attained, the saddle-nut A2 a self-opening die-head carried upon said i has arrived at the gap F2 in the lead screw secondary saddle, a resiliently acting bolt 115 F whereby the travel of the saddle A is carried upon one of said saddles, and a co arrested at the moment at which the die operating member carried upon the other he’ad E is arranged to be opened by the saddle and adapted to be engaged by the 55 known automatic means, which are appro aforesaid resiliently acting bolt at a pre priately adjusted for this purpose. After determined relative position of the two 1,20 this, the cross slide B is moved to cause the saddles. plunger H to'disengage the notched mem In testimony whereof I have signed my ber J, the die-head E is withdrawn by a name to this speci?cation in the presence of 60 rearward movement of the turret slide, the two subscribing witnesses. parting-off tool B3 is employed, and the ma ARTHUR IAROLD LLOYD. chining operation is then completed. 1Witnesses : It will thus be seen that the invention ALBERT BROWN, providessimple and automatic means for ANNIE LOUISE WADE.