US2190208A

US2190208A - Chucking machine and method

Info

Publication number: US2190208A
Application number: US116392A
Authority: US
Inventors: Sven E Green
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1936-12-17
Filing date: 1936-12-17
Publication date: 1940-02-13
Anticipated expiration: 1957-02-13

Description

Feb. 13, 1940. s. E. GREEN 1 cnucxmq MACHINE AND METHOD 8 Sheets-Sheet 1 Filed Dec. 17, 1936 m I N E I. E R M V m E .I N w 5 3 Q mm Q J F mm Na l. qww QQN l, ed a QQN mu mm.

ham

' HIS flTTO/V/VEY Feb. 13, 1940. s. E. GREEN 2,190,203

' CHUCKING MACHINE AND METHOD Filed Dec. 17, 1936 8 Sheets-Sheet 2 24 36 V k Wm INVENTORJ JVEN E. GREEN, Y awe fl mmo Feb. 13, 1940.

s. E. GRE EN CHUCKING MACHINE AND METHOD 8 Sheets-Sheet 3 Filed Dec. 17, 1956 I775 HTTORMEK Feb. 13,, 1940. s. E. GREEN CHUCKING MACHINE AND METHOD Filed De c. 17, 1956 & Sheets-Shegt 4 Feb. 13, 1940.

s. E. GREEN CHUCKING MACHINE AND METHOD Filed Dec. 17; 1936 m. w m

w Mm M v /a w. M 8 W M w mm 22 mm mfl V i a H/S HTTOR'IVEK Feb. 13, 1940.

s. E, GREEN 2,190,208

CHUCKING MACHINE AND METHOD Filed Dec. 17, 1936 s Sheets-Sheet s F/Ez/ I- [Q ii 0 1 in L E:

iv v V ll A m j 394 3% I/vz/E/vTok: EVEN E. GREEN,

' 11/; HTTORNEK Feb. 13, 1940. s. E. GREEN CHUCKING MACHINE 'AND METHOD a Sheets-Shet 7 Filed Dec. 1 1956 Flaw/6 mm m w lllll I m 3 N. E T y. r a wa m M N 3 a M 2 v a 4 8 M a 4. w/w 8 0 2 J 7 M /m\ m l W A; w w G Y 33 h a 8 3 m w 4 6M 6 w w M4 AM FebQlS, 1940. v v GREEN 2,190,208

GHUCKING MACHINE AND METHOD Filed Dec. 17, 1936 a sheets-sheet s Patented Feb. 13, 1940 on cKiNc MACHINE Asn-Mmnon Sven E; Green, Bristol,.Conn., assignor to Gen- Y era! Motors Corporation, Detroit, Mich, a

corporation of Delaware Application December m. 1936, Serial No. 116,392

24 Claims. (01. '29-38) This invention relates to chucking machines. and methods and comprises all of the features of novelty herein disclosed. An object ofv the invention. is toprovide a machine and a method for completely machining all surfaces of a work-. piece or of a pairof work-pieces at one l'randling of a single work blank. Another object is to provide suitable attachments for existing multi spindle chucking machines such that more tools can be used and more operations can be performed. Another object is to produce a multi spindle chucking machine which Will reduce the expense of machining work-pieces as by eliminating the usual second handlingof the piece. Still another object is to provide an improved method a of machining work-pieces.

To these ends and alsoto improve generally upon devices and methods of this character, the

Fig. 3 is a cross sectional view taken in the plane of line 3-3 of Fig. l. 1

Fig. 4 is a sectional view of an attachment taken about on the line l4 of 2.

Fig. 5 is an end View of a Work. spindle with its chuck removed.

Fig. 6 is an enlarged sectionv of details at one end of a chuck operating rod. H Fig. '7 is a section on the line l--l of Fig.4.

Fig. 8 is a front View partly in section of the keying device for the quill. A

Fig. 9 is a sectional view taken on the line B'9 of Fig. 2.

40. Fig. 10 is a sectional View taken on line Illill v In the illustrated construction, there are six .spindles, each having chuck jaws ill to grip a of Fig. 9. v

Fig. 11 is a sectionalview of a chuck operating cylinder and its controlling valve.

Fig. 12 is a front View of a tool and its carrier.

chucks.

Fig. 16 is a sectional view of aportion of the turret and associated fluid mechanism for opafim crating the spindle clutches.

Fig. 15 is a sectional view of the. valves which control chucking and driving of the turret Fig. 17 is a front elevation of Fig. 16 with parts broken away and in section.

Figs. 18 to 24 are sectional views indicating the sequence of operations on a work-piece.

. Figs. 25 to 31 are sectional views indicating 5 the sequence of operations to produce two fin-- ishedarticles from a single piece. C First outlining the general operation, awork blank such as a hollow sleeve, is chucked upon one of the rotary spindles of a carrier or turret 0 which is intermittently indexed to carry the piece 1 successively to a plurality of stations for machining operations by suitable tools. When the piece returns to the loading station; it is released and transferred to an auxiliary chuck whichis advanced to gripthe piece and their retreats toaworking station for further treating the work by suitable auxiliary tools. Meanwhile a new piece is chucked at the loading station and is carried around to the successive stations. 20' i This transfer of the piece to the auxiliary chuck enables the auxiliary tools to operate upon those surfaces which were previously. grasped by the jaws of theturret chuck and so prevented. access of tools to such surfaces. the piece. not only effects economy by eliminating a subsequent handling and chucking of the piece on another machine but also contributes to accurate. chucking and consequent concentricity. of inner andouter surfaces because the trans- 30. fer is mechanically effected. Further important economy results because two articles can be completed from a single Work blank of slightly more than double size to allow for severing and that double size blank can be forged or otherwise p'ro- 35 duced more economically than two single blanks. The numeral 2 indicates a base supporting a main frame 4 in which is journalled for indexing movement, a horizontal turret 6 carrying a series of individually rotatable work spindles 8. 40

work-piece W, the chucks at the various stations being indicated by the letters A, B, C, D, E

and F. The indexing of the turret lithe driving of the work spindles. 8, and the actuation of the chuck jawslllis not per se apart of the present invention and maybe controlled by any suitable mechanism suchas indicated in the patents to Gridley et al. 2,055,l34 and 2,055,435 granted Sept. 22, 1936; g l

A main tool carrier ii! of hexagonal form is provided on each face with slots i l to receive suitable tools as required, the tool carrier being guided for reciprocating movement on a sup- The. transfer of 25 able and slidable shafts 5i! and 52 project from porting sleeve I6 projecting from the main frame 4. The tool carrier is fastened to a slide block I8 which slides on ways 26 supported by a cross member 22 which is bolted to pedestals 24 projecting upwardly from the base. The tool carrier I2 and the attached slide block I3 may be reciprocated by any suitable mechanism such as a cam-operated bar .28 projecting from the sleeve I6 and threaded at the outer end in nuts 28 confined to the slide block IS-by an end cap 3%. ions so that, by inserting a suitable tool in a recess 32 of the end cap, initial adjustment of the tool carrier with respect to the turret can be effected in a manner well known.

Shafts

34 and 36 are rockably mounted in the pedestal 24 and usually carry arms 38 one of which is shown in Fig. 3 as provided with slots for T-bolts 49 for attachment of a tool holder. Ordinarily a tool mounted on the arm 38 operates on a work-piece secured to one of the turret carried work spindles at station A but,

in the present machine, an extension arm 42 is bolted to the arm 38 and has slots for T-bolts 44 which clamp on a tool holder 46 with a tool 48 which operates near station F on a workpiece after such work-piece has been transferred to a supplemental chuck as will appear. Rock the main frame 4 into bearing

bosses

54 and 56,

respectively, on a supplemental casing or frame 58 which is bolted to the cross member 2.2. The

supplemental frame is rigidly braced from the main frame near the top by bracing bars Bil and 82 which project from the main frame and are secured by set screws 64 to bosses on the supplemental frame. Shafts 50 and 52 carry'tool holders (not shown) with suitable tools for operating on the work in the turret-carried chucks as will appear.

In the supplemental casing or frame 58 (Figs. 1 to 4) are mounted an auxiliary work spindle and a quill with an actuating mechanism which effects rotation of the spindle, longitudinal shifting and locking of the quill, chucking and unchucking, there also being a' cam-operated device (Fig. 9) to swing a supplemental tool for operation on the work after it is transferred to the auxiliary work spindle. For rotatably driving the auxiliary spindle, a power shaft iii journalled in bearings l2 and M on the main frame is se cured by a coupling it to a short shaft I8 which is journalled in bearings enclosed by cover plates 19 on a hollow standard 80 fastened to the supplemental frame 58. A sprocket wheel 82 is connected by a chain 8 with a sprocket wheel at keyed to a shaft 88 journalled in the supplemental frame upon ball bearings 9t and 92. The bearing t2 which is a double row ball bearing has its inner race ring clamped on the shaft against the sprocket wheel 86 by a nut 94. The outer race ring is clamped against a shoulder in a flanged bearing housing 96 by a cap 98, the

- housing 86 being removably secured to the frame The pinion E02 drives a gear Ifit 'journalled on.

a countershaft H33 and meshing with an elongated gear l ill which is keyed to a hollow spindle II 2 and held from longitudinal movement on the spindle by a screw I I4. The spindle is jour- The nuts 28 are formed externally as pin ment of the spindle.

nalled for rotation in a quill II6 which is capable of sliding movement without rotation in The outer race rings are spaced by a sleeve I30 and are locked against endwise movement in the quill between a shoulder and an end cap I32, the end cap cooperating with a companion cap I34 to form a felt holding seal engaging an enlarge- Near the other end, the spindle is journalled in a double row ball bearing E36 whose outer race ring can slide in the quill and whose inner race ring is clamped against a washer engaging a shoulder by a tubular projection I33 threaded on the spindle and forming an extension of a chuck-operating cylinder Hit. Lubricant is retained and foreign matter excluded by a felt washer confined between a washer and an end cap ItI fastened to the end of the quill.

The cylinder Hid has a piston I42 connected to'a rod M l which passesthrough a packing gland i l-ii in the spindle to thread into a draw bar MS which operates a chuck. As best shown in Figs. 5 and 6, the draw bar has a flattened portion engaged by a flattened area on the interior of a D-washer I52 which is secured in the spindle by a pin I54, thus compelling the draw bar to rotate with the spindle but allowing endwise movement.' The front end of the spindie is enlarged and a chuck body I56 is secured to it by screws I58, a key IEO being fastened to the enlarged end of the spindle by screws and entering a slot in the chuck body to insure against relative rotation. A detachable nose piece I62 has an enlarged portion threaded in the end of the chuck body and has inclined cam surfaces for jaws orwedges I54 adapted to be expanded on the inside of a work-piece W which is located endwise by a locatingring I56 secured to the enlarged portion of the nose-piece. The ring also prevents the wedges from dropping out when the work is released. To expand the wedges, a collar. S68 is secured to the end of a bolt I I0 which is keyed to the nose-piece and threaded in the front end of the draw bar I48. The bolt I'ill is threaded in the draw bar when the nosepiece is threaded home. Endwise movement of the draw bar to the right expands the wedges to grip the work internally. Endwise movement in the opposite direction releases the wedges which are forced back down the inclines of the nose-piece by plungers H2 engaged by a collar Ild surrounding the bolt I'll) and backed up by check nuts. The work is pushed off the wedges by ejector pins H6 whose enlarged rear ends are engaged by coil springs I'IB housed in recesses of the collar i'M.

The chuck spindle H2 and quill IIE are shown in Fig. 4 in the position they occupy while the work-piece W is being treated. The quill is normally locked against endwise movement by a locking bar 5823 which enters a recess formed by wear plates I82 inserted in the quill. The locking bar is urged to locking position by a coil spring I 84 which is backed up by a pilot screw I86 1 288. cam 2H1 formed by plates M2 and 2M attached to the periphery of the cam drum 98 and acting threaded for adjustment in the top of a housing H88 having a guiding wear plate I98 and a rear cover I92. Projecting from the locking bar through a'slot in therear cover is a cam roller I9 5 adapted for operation by a cam I95 fastened to the end of a rotary cam. drum Hill which is keyed to a rotary shaft 200 and fastened to it by a set screw. The drum and shaft are retained endwise by thrust washers Zill engaging bosses on the frame 58. The cam Hit withdraws the locking bolt at the proper times to allow the quill and spindle to advance for the purpose of taking work pieces successively from the work spindles 8 when the latter reach the station F.

The quill H6 is held against rotation in its bearings H8 and 120 by a key 2132 (Figs. 7 and 8) which enters an elongated slot 2% in the quill, the key being carried in a recess of a plate 206 attached to the frame 58 against a gasket The quill is actuated longitudinally by a on a cam roller 2H5 rotatably mounted on a stud secured to a slide 220. The slide has limited. movement in a dovetail way 222 formed in a block: 2% which is fastened by screws 226 and v "station F to transfer the piece from a turret chuck to the auxiliary chuck. The turret chucks and the auxiliary chuck rotate in the same direction and at the same speed to facilitate transfer.

The cylinder MB travels with the spindle H2, and the operation of its chuck-operating piston is timed to release the work before the chuck takes on a new piece from a turret chuck, and to grip the new piece before the quill returns. A cylinder head Mil is secured to the outer end of the cylinder and has a cylindrical extension 252 with two spaced

annular grooves

264 and 2%. A port 248 leads from the groove 24 to the outer end of the cylinder. A central port 25;} leading from the other groove communicates by

passages

252 and 254 with the opposite end of the cylinder. A sleeve 258 surrounds the extension Ni! and is retained by a plate 26%. The sleeve has openings for two pipes 262 and 254 (Fig. 11) which communicate with the grooves 2M and 2% and with a valve casing 265. These pipes are flexible because the sleeve 258 travels longitudinally although it does not rotate with the cylinder head extension 242 which is journalled in it. The valve cornprises spaced pistons 268 adapted to alternately put the

pipes

262 and 2% in communication with a pressure line 216. There are also two spaced

exhaust pipes

212 and 2 714 which alternately exhaust the fluid from the

pipes

252 and 264. The

valve stem has a yoke 2l5to rotatably support a cam roller 218, the yoke having a lug 235i engaging an extension 282 on one of the valve caps to of the supplemental frame.

216 and to an anchoring stud 288 so that the cam roller is held against the cam.

Another instrumentality operated by cams on the cam drum see is a sliding and swinging shaft carrying a supplemental tool to operate on each work-piece after it has been transferred to the auxiliary spindle. (See Figs. 3, 9 and 10.) The shaft 29% is

journalledin bosses

292, 294 and 296 Its endwise move-. ment is controlled. by a cam slot formed by cam plates 2% and 383 on the periphery of the drum and straddling a cam roller 362 journalled on a stud projecting from a block 384. The block is loose on the shaft although confined between collars till pinned to the shaft. The block is held from turning with the shaft by an extension 308 which is guided on a rod 3H3 fixed in the supplemental frame. The cam roller is thus held from swinging out of the can). slot when the shaft is swung.

Rocking or swinging movement of the shaft 299 is controlled by an arm 362 having its hub provided with a key ti l entering an elongated slot 3N5 in the shaft. The arm. carries a cam roller Sill arranged for actuation by a segmental cam plate EQQKFig's. 3 and i) attached to a ring 32! fastened around an extension at the end of the cam. drum 598, a coil spring 3122 anchored to the arm and to the frame urging the roller against the cam plate. To insure swinging of the arm in case the spring fails, another segmental and outside'cam plate 325 is attached to the ring 32!. A tool carrying arm. is clamped to the outer end of the shaft iii-iii. Adjustablysecured to the arm by screws 252i is a tool holder 328 with spaced ribs 3% (Fig. 13) having opposed adjusting screws straddling a lug 33% on .a ratchet 336. A tool 338 has a companion ratchet to engage the ratchet and is secured to the tool holder by a clamping bolt Coarse angular adjustment of the tool is provided by the ratchet faces and fine adjustment by the screws 332. The tool opiiifi. Its inward swinging movement towards the work is limited by an abutment plate 342 (Fig. 3) mounted on a bracket 3- 53 secured to the frame 58 and engaged by an arcuate locating plate 344 adjustably secured in an arcuate guide in the arm 326 by a clamping screw 3%. The arcuate plate SM is accurately located in its guide by a screw .erates on the work carried by the auxiliary chuck Milthreaded in the arm and adapted to abut against the end of the arcuate plate.

The cam drum 588 carries a gear 3565 (Fig. 41) secured to it by the same screws which secure the ring 32!. The gear is driven by a gear 352 keyed to a short shaft 354 vhi-ch is journalled in a boss 356 of the supplemental frame 58. At the outside of the frame is a collar 358 to hold the shaft from. endwise movement. The shaft is connected by a coupling 3% to a short shaft 362 (Fig. 1) having a similar coup-ling 35d to secure it to a timing shaft 355 which projects from the main frame. One of the collars of coupling 358 has timing can be varied.

Referring to Figs. 14 to 17, each work spindle ll on the turret 5 is provided with a grooved clutch collar tall! urged to clutching position by a coil spring 372, so that the spindles when in working positions will be rotatably driven from any suitable power source. fork 3M engaging each clutch collar is guided on a rod 3'55 carried by projecting flanges 3T3 on the turret B. Each fork for each spindle clutch has a cam roller 33!] adapted for actuation by a cam 382 on a slide 384 which is guided by bars 386 and 383 projecting from the main frame and carrying coil springs 3% which urge the slide to a retracted position. The slide is adjustably secured by nuts to the 3 threaded end of a piston rod 392 having a piston 394 in a cylinder 396. The above mentioned springs urge the piston against an adjustable stop screw 398 but the piston can be advanced to throw out the clutch. To look the clutch out temporarily, as when a new piece of work is being chucked on the work spindle, a collar Mill on the piston rod is adapted to ride behind a latch hook 462 on an arm which is pivoted at 464 on a bracket 466 projecting from the cylinder.

Fluid under pressure can be admitted behind the piston through a passage 468 having an adjustable throttle valve Mil, the passage communicating with a chamber 2 containing a slidable piston valve Al i with two spaced pistons. Fluid is admitted between the pistons from a pressure line 416 and will communicate with the passage 468 when the valve 494 is slid to the left in Fig. 15. Normally the passage 408 is open to an exhaust line M8. The valve has a projecting stem 320 with two annular grooves adapted to be engaged alternately by a spring pressed ball detent 42! to hold the valve in its extreme positions. A link 4722 connects the valve stem to an arm 424 pinned to a rock shaft 426 which projects through the frame and carries an actuating handle 428. By rocking the handle, the piston Valve M4 can be slid to the left to advance the clutch operating piston 394 and throw out the spindle clutch to 3.5,, permit chucking and it can be shifted back to the right to let the piston 3% come back under spring pressure to throw in the spindle clutch and start spindle rotation after chucking.

For successively controlling the chucks on the work spindles 8 as the latter reach the loading station F, there is a second valve chamber 43!] with a piston valve 4132 comprising spaced pistons in communication with the pressure line 496, the

chamber Q30 having two exhaust lines 43 and 436 l for alternately exhausting fluid from ports 538 and Mill which lead to a distributor (not shown) having fluid connections with cylinders on all the spindles. Each cylinder M2 has a piston 4% connected to the draw rod ME of the respective chuck. Patent to Gridley 2,055,435 above mentioned has a somewhat similar fluid system. The piston valve 432 has a stem M8 provided with grooves adapted to be engaged alternately by a spring pressed ball. detent l5il to hold the valve in its extreme positions. A link 452 connects the valve stem to an arm 454 of a lever which is secured to a sleeve 456 which serves as a journal for shaft 426 and is rockably mounted in the frame and operated by a handle 458. In the position shown in Fig. 15, pressure fluid goes throughthe port 438 and thence to the chucking cylinder 642 to hold the chuck jaws closed on the work. By swinging the lever, the piston valve 432 can be shifted to the left to put the port Mill in communication with the pressure line M5 to thereby operate the chucking piston to open the chuck but the piston valve 432 is preferably operated automatically in this direction. For this purpose, a lever arm '46!) is connected by a link 9-62 to a bell crank lever 464 which is connected by a link 4555 with a second bell crank lever M6 carrying a cam roller 4M in the path of a cam M2 on a cam shaft Md. The cam is timed to actuate the valve and open each chuck after such chuck has reached the loading station F and before its spindle has been stopped from rotating by the throwing out of its clutch.

On the stem 448 is a collar 416 which normally engages an inclined cam surface on an arm 418 which is a part of the same lever which carries the latch hookAQZ. Whenever the sleeve 456 is swung in a direction to shift the piston valve 432 to the left, the collar 416 releases the arm 478 so that the latch hook is ready to dropdown behind the other collar M90 as soon as the clutch-controlling piston rod 392 is advanced, thus affording a means to insure the holding out of the work spindle clutch 316 until a work-piece is chucked.

Figs. 18 to 24 inclusive indicate operations which can be carried out by the machine. The rough work is indicated as an internally-ribbed sleeve to be made into a double row, outer race ring, and each piece is inserted in the chuck jaws H] of one of the turret spindl s 8 as such spindle reaches the loading station F. The turret then indexes to carry the piece to station A for operation by tools, such as a turning tool 486 shiftable axially along the outside of the work, a rough boring tool 332 shiftable axially, and a facing tool 484 swinging radially. At station B, there may be a further turning operation by a tool 486 and a further boring operation and a rounding of corners by a tool 488. At station C, a tool 49!] moves axially and radially to form a rough ball race and an internal rounded corner while a tool 482 faces the end and forms an external rounded corner. At station D, a boring tool 694 cuts ball races and finishes the inside corners while a tool 496 faces and finishes the outside corner. At station E, a boring tool 498 finishes the ball races. At station F, the piece is released from the turret spindle jaws l0 and transferred to the chuck I56 on the supplemental spindle whose quill retreats to a working and locked position where the tool 338 above mentioned turns the exterior surface in the region where the chuck jaws Ill were previously gripping the piece. At this same position, the tool 48 faces the now accessible end and rounds the corner. Thus all surfaces of the piece are finished at a single handling by one machine. When the piece is thus transferred to the supplemental chuck, a new piece is inserted in the chuck jaws at station 15 ready to be indexed to station A.

Figs. 25 to 31 inclusive illustrate how two articles can be completed from a single piece WE at a single handling by one machine. The piece may be a plain sleeve loaded at station F and first operated upon at station A by a turning tool 500, by a'boring tool 562, and by a recess forming tool 564. At station B, another turning tool 506 operates on the exterior and another boring tool 568 operates on the interior. Atstation C, there is indicated a recess forming tool m, a facing tool 5l2, and a boring tool 5M. At station D there is a tool 5; for facing one end and rounding the corner while a boring tool 558 completes a pair of raceways. At station E, a cut-off tool 526 severs a completely machined single row race ring W2 from the piece WI. The remainder of the piece continues to station F where it is transferred to the supplementary chuck Hi6 and treated by the tools 338 and 68 to complete another race ring.

The tools above referred to are merely illustrative of suitable tools which can be used as required. They show that a work-piece can be treated on some surfaces when in the turret chucks, followed by transfer to a supplemental chuck for operation on surfaces previously engaged by the jaws of the turret chucks. While the turret chucks are shown as gripping the exterior of the work and the supplemental chuck with the quill for operating the chuck; substanhas been operated upon'by all of the usual tools pertaining to the turret stations, such work-piece finally returns to the loading station F. It is still in the chuck? and its spindle is rotating but no work can be performed on those surfaces which are engaged by the chuck jaws it as long as the piece is held by them. At this time, the

quill Ht of Fig. a carrying the supplemental spindle H2 becomes unlocked by the cam l t and is advanced towards and in line with station F by the cam 2H]. Its spindle rotates at the same speed as the turret chuck F and turns in the same direction, While the rotating piece is I still gripped and centered by the turret chuck, the supplemental chuck wedges ltd are expanded to grip the piece internally under control of the piston Hi2, valve 2% and cam 284. N2 of Fig. 1"] now shifts the piston valve 332 to the, left and the chucking piston d i l of the turret chuckis operated to release the work-piece so it can be carried away by the supplemental chuck when the quill returns to its outward, locked position where work is to be performed by the

tools

48 and 338 on the hitherto inaccessible work surfaces. The turret spindle at the loading station F is still rotating. Handle 328 is now rocked to move the other piston valve li ito the left thereby advancing the clutch con trolling piston 394 to release the, turret spindle clutch 37B and stop the rotation of its spindle.

The clutch is held out temporarily by reason of the safety latch hook til? dropping down behindthe collar dilll. A new piece is now put in the chuck F. Next, the lever 658 is swung manually in the opposite direction and the piston valve 432 shifts to the right to cause the turret chuck piston did to operate its chuck to grip the new piece. The collar tit raises the latch hook Mid and frees the clutch piston 3% although the latter is still held temporarily in its advanced position by fluid pressurefrom the line H5. Next the other handle 328 is swung back to slide the other piston valve did to the right to thereby let the clutch piston 39% return by spring pressure and throw in the clutch tojstart rotation of the turret spindle.

Thereafter the turret indexesthe spindle to the'A position for operation by the tools and advances all of the other spindles one station. Meanwhile the work transferred to the supplemental chuck lfit is operated upon by the twotools it and 338 and the work is finally released from the machine in a completely machined condition on all surfaces.

I claim: 1. In amachine of the character described, a frame, a quill mounted to slide endwise in the frame, a spindle journalled for rotation in the quill and having a chuck, means for locking the quill in retracted position, a cam for retracting the locking means, and a cam for sliding the quill "to advance the chuck to a loading position; substantially as described. H

2. In a machine of the character described, a frame, a quill mounted to slide endwise in the frame, a spindle journalled for rotation in the quill and having a chuck, means for sliding the quill to advance the chuck to a loading position, and a cylinder and piston unit shiftable The cam tially as described.

3. In a machine of the character described, a frame, a. quill mounted to slide endwise in the frame, a spindle journalled for rotation in the quill and having a chuck, means for sliding the quill to advance the chuck to a loadingstation, a cylinder and piston unit shiftable with' the qulil for operating the chuck, a valve controlling said unit, and a cam for operating the valve; substantially as described.

4. In a machine of the character described, a trance, a quill mounted to slide endwise in the frame, a spindle journalled for rotation in the quill and having a chuck, a cylinder and piston unit shiftable with the quill for operating the chuck, a valve controlling said unit, a cam for operating the valve, and a cam for sliding the quill to advance the chuck to a loading positicn; substantially as described.

In a machine of the character described,

a frame, a quill mounted to slide endwise in the frame, a spindle journalled for rotation in the quill and having a chuck, means for locking the quill in one position, a cam for retracting the locking means, a cylinder and piston unit shiftable with the quill for operating the chuck, a cam for controlling said unit, and a cam for sliding the quill to advance the chuck to a loading position; substantially as described.

kiln a machine of the character described,

a frame, a quill mounted to slide endwise in the frame, a spindle journalled for rotation in the quill and having a chuck, a gear within:

the quill and secured to the spindle, a driven mounted on the frame and projecting through an opening in the quill to drive the spindle gear, one of the gears being elongated, and means for sliding the quill to advance-the chuck to a loading position; substantially as described.

'1'. In a machine of the character described,

a spindle journalled for rotation and havinga chuck, a second chuck in alignment with the first chuck and adapted to grip or release a workpiece, means for advancing the first chuck to- .wards the second one, said advancing means having a yieldable member to provide lost motion when the first chuck engages the work-piece; substantially as described.

8. In a, machine of the character described, a spindle jcurnalled for rotation and having a ,chuck, a second chuck in alignment with the,

first chuck and adapted to grip or release a workpiece, means for advancing the first chuck towards the second-one, a rotatable cylinder and piston unit connected with the spindle to advance therewith, the cylinder and piston also being relatively movable for operating the first chuck,

and means for supplying operating fluid to said unit; substantially as described.

9. In a machine of the character described,

a spindle journalled for rotation and having a chuck, a rotatable cylinder and piston unit connected to the spindle for operating the chuck, and means for axially reciprocating the spindle and unit; substantially as described. 10. In a machine of the character described,

a turret having work spindles, each spindle having a clutch to control rotation and a chuckj'm to grip or release a workpiece, a piston and cylinder unit to operate each chuck, a piston and cylinder unit to operate all the clutches in sequence, a valve to control the chuck operating pistons, a valve to control the clutch-r controlling valve to release a work-piece, means for operating the clutch controlling valve to throw out a spindle clutch, means for latching out the spindle clutch while loading the chuck, means for operating the chuck controlling valve to cause gripping or" a new piece and release of the latch, and means for operating the clutch controlling valve to control renewed driving of the spindle; substantially-as described.

11. In a machine of the character described, a turret having work spindles, each spindle having a clutch to control rotation and a chuck to grip or release a work-piece, a piston and cylinder unit to operate each chuck, a piston and cylinder unit to operate all the clutches in sequence, a latch, valves to control the chuck operating pistons and the clutch operating piston, and means to operate each valve to throw out and latch a clutch until a new piece is gripped in the chuck; substantially as described.

12. In a machine of the character described, a turret having work spindles, each spindle hav ing a clutch to control rotation and a chuck to .grip or release a work-piece, a piston and cylinder unit to operate each. chuck, a piston and cylinder unit to operate all the clutches in sequence, a valve to control the chuck operating piston, a valve to control the clutch operating piston, means to operate the clutch controlling valve to throw out a clutch and latch it, and means to operate the chuck controlling valve to grip a new piece and release the latch; substantially as described.

13. In a machine of the character described, a work spindle having a clutch to control rotation and a chuck to grip or release a workpiece, a piston and cylinder unit to operate the chuck, a piston and cylinder unit to operate the clutch, a latch for the clutch, a valve to control the chuck operating piston, a valve to control the clutch operating piston, means to operate the clutch controlling valve to throw out the clutch and latch it, and means to operate the chuck controlling valve to grip a new piece and release the latch; substantially as described.

14. In a machine of the character described, a Work spindle having a clutch to control 1'0- tation and a chuck to grip or release a workpiece, a piston and cylinder unit to operate the clutch, a latch for the clutch, a valve to control the unit, means for shifting the valve to throw out the clutch and latch it, and chuck controlling means for releasing the latch; substantially as described.

15. In a machine of the character described,

. a work spindle having a clutch to control ro- ,tation and a chuck to grip or release a workpiece, a piston and cylinder unit to operate the chuck, a valve to control the unit, means to throw out the clutch, a latch for the clutch, and

means for shifting the valve to operate the chuck and release the latch; substantially as described.

16. The method of machining a pair of articles from a single piece of substantially double size with an extra length for severing and separating the articles, which consists in chucking the double size piece by gripping only a portion pertaining to the rear end of one article to leave exposed for machining all the portions pertaining to the other article plus a portion of said one article, machining said exposed portions pertaining to said other article and a poroperating piston, means for operating the chuck tion of said one article, rechucking by gripping another portion of the double size piece to leave exposed that portion at the rear end of said' one article which was previously gripped, and

machining said previously gripped portion; substantially as described.

1'7. The method of chucking and machining a pair of articles from a single piece of substantially double size with an extra length for severing and separating the articles, which con-"- sists in chucking the double size piece by gripping only one end portion thereof to leave all other portions exposed, machining all exposed portions pertaining to one article, rechucking the pieceby gripping a machined portion to expose said previously gripped portion, and machining the newly exposed, previously gripped portion; substantially as described.

18. In a machine for chucking and completely machining a pair of articles from a single piece of substantially double size with an extra length for cutting ofi, a chuck for gripping only one end portion of the double size piece to leave all other portions exposed, means for machining substantially all exposed portions, means for cutting off some of said machined portion to release cne completed article from the piece held in the chuck, a second chuck for gripping a machined portion of the remaining part of the piece while the previously gripped portion remains gripped by the first chuck, means for operating the first chuck to release its hold on the piece, and means for machining the newly exposed previously gripped portion to complete a second article; substantially as described.

19. In a machine for chucking and machining a pair of articles from a single piece of substantially double size with an extra length for cutting off, a chuck for gripping only one end portion of the double size piece, means for machining the exposed portion, means for cutting off said machined portion to produce one article,

a second chuck adapted to hold the remaining for cutting oif and releasing the machined por-' tion to produce a finished article, a second chuck for gripping a projecting surface of the portion remaining in the first chuck, means for thereafter causing the first chuck to release the piece, and

means for machining the previously gripped and newly exposed portion of the piece to produce a second article; substantially as described.

21. In a machine for chucking and machining a pair of articles from a single sleeve of substantially double size with an extra length for cutting ofi, a chuck for gripping a portion of the exterior surface of the sleeve, means for machining the exposed portion of the exterior surface and the interior surface, means for cutting oil the sleeve at an intermediate area to produce one article, a second chuck for gripping the interior surface of the remaining portion of the sleeve before the exterior surface thereof is released, and means for machining thenewly exposed ex.

terior portion of the sleeve to produce a secon article; substantially as described. I

22. In a machine for chucking and machining all surfaces of a hollow work-piece, a chuck for gripping one peripheral surface of the piece, means for machining the exposed portion of the peripheral surface and the opposite peripheral surface, a secondchunk adapted to grip said opposite peripheral surface while the piece remains in the original position and. is still gripped by said one peripheral surface, means for causing the first mentioned chuck to release said one peripheral surface, and means for machining the newly exposed portion of the piece; substantially as described. I 1

23. In a machine for chucking and machining a pair of articles from a single piece of substantially double size with an extra length for severing and separating the articles, a chuck adapted.

to grip only a portion pertaining to the rear a portion pertaining to the first article, means for machining the exposed portions pertaining to both articles, a second chuck adapted to grip another portion of the double size piece to leave exposed that previously gripped portion at the rear end of the first article, and means for ma chining said previously gripped portion; sub

stantially as described.

24. In'a machine for chucking and machining meansforfmachining all exposed portions pertaining to one article, a second chuck adapted to grip a machined portion to expose the previously gripped portion, and means for machining the newly exposed previously gripped portion to complete a. second article; substantially as described. l 1

SVEN EHGREEN.