USRE22621E

USRE22621E - Loading and unloading of work in

Info

Publication number: USRE22621E
Authority: US
Priority date: 1938-05-24
Publication date: 1945-03-20
Also published as: US2211722A

Description

March 20, 1945. w, GROENE r Re. 22,621

LOADING AND UNLOADING OF WORK IN MACHINE TOOLS Original Filed May 24', 1938 6 Sneets-Sheet 1 INVENTORS. W\LLU\M F-GROENE BY WALTER R.METER \L) owl m g- ATTORNEY.

w. F. GROENE arm. Re. 22,621.

Margh 20, 1945.

LOADING AND UNLOADING OF WORK IN MACHINE TOOLS 6 Sheets-Sheet 2 Original Filed May 24, 1938 INVENTORS. W\LL\AM F.GROENE ATTORNEY.

wmusss. WMJM March 20, 1945. w'. P. GROENE ETAL LOADING AND UNLOADING OF WORK IN MACHINE TOOLS Original Filed May 24, 193B 6 Sheets-Sheet 3 E II Q m 3 3 m w N h m w x A2 Mr W 2. Q A 3 N2 2* $1 mr o: .or or m rr w 2w 1 3 E on w A ww\\\ w //J s m. 5 -m mm WILUAM F GROEHE WALTER ameyea ATTORNEY.

March 20, 1945.

W. F. GROENE ETAL LOADING AND UNLOADING OF WORK IN MACHINE TOGLS 6 Sheets-Sheet 4 Original Filed May 24, 1.938

m9 $7 3: A m2 INVENTORS.

\N'lLLlAM F-QRDENE BY WM. ER R.METER 5' ATTORNEY:

W. F. GROENE ET AL LOADING AND UNLOADING OF WORK IN MACHINE TOOLS 6 Sheets-Sheet 5 Original Filed May 24, 1938 R 5.. mm M wjmeL .m m 5 w mm mm .A fi w 8 m m a M w M.

w. F. GROENE ET AL Re. 22,62'l LOADING AND UNLOADING OF WORK IN MACHINE TOOLS March 20, 1945.

Original Filed May 24, 1938 6 Sheets-Sheet '6 wow: 52; mw kflfifid 02 z v o2 02 5 J E a: E Q: 7 2: 32:52 mw fiaflfi 555". M ME m m E 02.] 1 r 09 a;

02 3 Rm; 553 2: 555:2: 3: x53 Hm: x53 o: 3:25;

auzmzi flag Um @u i mm H. m m WZhR 0 mm m. w P A m M 1 m M Reissued Mar. 20, 1945 LOADING AND UNLOADING onwolm 1N MACHINE rooms I William F. Groenc and cinnati; Ohio, assignors MachineTool Company, corporation of Delaware Original No. 231L722, d

riaINo.209,'738," May 2 reissue September 15,

35 Claims.

This invention pertains to loading and unloading *of work in machine tools and is particularly related to crankshaft lathes of the center drive type of a character shown inPatent 2,069,107, dated January26, 1937, in which thecrankshaft to be machined is chucked and rotated by means of one or more center drive chucks and-has its ends I supported by centers while cutting tools operate on the various bearing-portions-of said crankshaft.

Heretofore in lathes of this character it has always been a major difliculty to provide proper means to load and unload the crankshaft into the center drive-chucks. One difficulty hasbeen that caused by the tailstock each side of the center drive-chucks which prevented the insertion and removal of the work in thecenterdrive'chuck'on the axis-of rotation of the chuck and"- crankshaft. In order to avoid moving the tailstocks it"was found necessary to make the center' drive gears relatively -large'in diameter, in fact so large as to make the machine difficult to operate as these large center drive gears necessitatedlarge housings-which projected outwardly to the-front of the machine and interfered with 'theoperators access to the cutting tools and chucking mechanism in the ring gears. In fact these ringgearsbecame so large in instances where loading devices were used that it was practically impossiblefor the operator toget at certain of the tools, for example the cutting tools 22 on the tool bar l8;-and also-difllculty-was found in gaining access to the various clamping devices in the ring gear chucks. Another defect of the large ring gears was'the difficulty in presenting the/tools to the work from such a far removed position when the ring gears were so large-as to prevent putting-the tool supporting devices sufficiently close to the workpiece beingmachined for proper stability of the tools. This large ring gear construction also presented much greater expense in manufacture, particu- 3 larly in instances where anti-friction bearingsor other highly expensive bearings-of large diameter were required. And also in cases where plain bearings were used in' conjunction with" these large ring gears the surface velocity'of the bearing surfaces necessary to properlyrotatethe crankshaft at cutting speed were so highas to create serious problems of lubricationand -wear in the bearings.

Also in the cases where the tailstocks are fixed and relatively large ring gears are utilized it-was necessary after moving the crankshaft into the chucking devices to-lower it to the'chuckingmembers and to raiseit-again after machining'of' the crankshaft before it was removed outwardly from the ring gear chuck. This resulted inconsiderableefiort on the part of the operator especially when lt-was done manually. This-also required considerable carefulness of operation-on the part Walter E. Meyer, Cinto The R. K. Le Blond Cincinnati, Ohio; at

atcdAugu'st 13,1940, Se-

1941, sci-arm; 410,922

1938. Application for of the-operator. "Whereloading devices were used, whichdoading devices-were necessarily of elaborate -construction to-=-efiect these various movements mechanically, the operator had to carefully actuate them in' their-proper sequence. In instances where the tailstocks have been movedin the past-the work was invariably leaded manually or'by use-of the usuai'ca-ble-and hook crane. Such loading and unloadingwas particularly difficult ininstanceswhere morethan one center'drive' chuck-was used be'ca-use of the inabi1'-- ity toproperly hold the crankshaft-when thread-- ingit through the-'chucking'devi'ees. fTheresult was that the ring gears'hadto-be made relatively large to permit the crank to be loadedmanually without striking the chuckingmechanism, and also, the cutting tools had tobewithdrawn a relativ'ely great distance from the axis 'of' rotationof the chuck so that they would not be struck by'the crankshaft when so loaded. This-*method-obviously wasvery cumbersome and-extremely difiicult for the operator to perform consuming considerable time and energy on "his-part. Another defector the abo-vcme'thodwas that there was no accurateway of guiding-the crankshaft into and outof theychucking devicesindependent-of the skill and' eifort-exerted on the partof the operator.

In instances where the former typeloa'ding-devices -were used itwas found that" considerable efiort'was required on the part of the operator to roll the various loading-cranes with the work hanging thereon into and out of the chucking devices commensuratew'ith the high production required of thes machines. -Withthe structure here developed, this former effort was substantiallyreduced to a minimum while at the same time-greatly reducing theamount of mental -efiort and skill necessaryon the part-of the operator-in actuating the former loadingdevices ina definite sequential-manner and in practically eliminating ail costly loading devices.

-Furthermore with these former methods including' the formertype loading devices, it-was impossible tosimultaneously load and unload the crankshafts from the chucks. It-.-w'as-' necessary first to remove the finished'work piece before a rough work piece was again loaded in the chuck whereas with the present method we are now able to simultaneously eject the" completed crankshaft from the center drive chuck while loadingan unmachined shaft therein. 7 And furthermore in the former devices particularly where'one device is utilized for loading and another for unloading of the-work, it was necessary forthe operator to move from one-side of the machine to the-other for operating the respective cranes which, of course, consumed time andeffort'on the part of the operator and cut down the productiveoutput of the machine. i

With these former difficulties clearly in mind,

it is therefore an object of our invention to provide means for easily loading and unloading crankshaft in a center drive lathe on the axis of rotation of the center drive chucking devices and to provide means for ejecting said crankshafts from chucking devices with a minimum of efiort on the part of the operator.

Another object of our invention is to provide in a center drive lathe chucking devices adapted to engage a crankshaft by means of machined locat- Another object of Our invention is to provide in a center drive lathe, means for supporting and rotating a crankshaft in exact centered and indexed position in the center drive chucks and means for stopping said center drive chucks at the completion of the cutting cycle at a predetermined indexed position relative to a loading and unloading arrangement comprising a. rail forming a substantially continuous track from one end of the machine through the center drive chucks to the other end of the machine for loading and unloading crankshafts in said center drive lathe. 1

Another object of our invention is to provide in a center drive lathe having one or more center drive chucks and tailstock each side of said center drive chucks, means for movingsaid tailstocks radially of the axis of rotation of said chucks and to provide means on each of said tailstocks comprising a loading and unloading rail, and

1 means for actuating said tailstocks radially for presenting either their centers or the loading and unloading rails in alignment with said chucking devices so that work may be supported at its ends or may be loaded or unloaded from said chucking deVices when the centers of said tailstocks are withdrawn radially from aligned position with the center drive chucks.

It is also an object. of our invention to provide in a center drive lathe one or more center drive chucks and associated tailstocks each side of said center drive chucks, both of said tailstocks being movable radially of the axis of rotation ofthe chucks and each incorporating a loading and unloading rail which may be brought in alignment with said chucking devices when the centers of said tailstocks are withdrawn radially from their work engaging position so that work may be loaded and unloaded from said center drive chucking devices by axially sliding said work with its axis coinciding with the axis of rotation of said chuck. 1

Another object of this invention is to provide in a center drive lathe a loading arrangement for axially sliding work from one side of the lathe to the other through said center .drive chucks while on the axis of rotation of said chucks so that the chucking mechanism will require a minimum of space and a relatively small ring gear and which will require an extremely small amount of movement for clamping and unclamping of the work by means of machined locating areas thereon and to avoid the necessity of moving any clamp or other clamping mechanism other than actuating a single clamping bolt to render the chuck efiective or ineffective in gripping the work piece.

Our invention also comprises a novel method of loading and unloading center drive lathes comprising premachining locating notches on the webs'of a crankshaft, placing said crankshafts on a loading rail carried on a movable tailstock of said lathe aligned with said center drive chuck,

.axially sliding said crankshaft from said loading rail past the cutting tools and into said center drive chucks wherein the chucking mechanism engages said crankshaft by means of said locating notches to accurately support and positively rotate said crankshaft in indexed position in the center drive chuck and to provide means for accurately stopping said center drive chuck in a definite predetermined indexed position relative to said loading rail to facilitate loading or unloading said crankshafts axially of said chucking devices.

And it is also an object of our invention to provide means for automatically moving the tailstock of a center drive lathe topresent a loading rail in alignment with the center drive chucking devices at the completion of the machining operation and to present its work supporting center in alignment with the chucking devices during the cutting operation.

Further objects and advantages of our invention will appear from the detailed description of the drawings in which:

Figure I is a right hand end elevation of a double center drive crankshaft lathe showing one of the movable tailstocks with loading and unloading rails and the associated center drive chucking device.

Figure II is a vertical transverse section through the lathe of Figure I on the line 11-11 of Figure III particularly showing the guide blocks on the tool bars and the construction of the center drive chucking devices associated with these blocks.

Figure II is a vertical section substantially on the line IIIIII of Figure I particularly showing the loading and unloading rails on the tailstocks, the guide blocks on the tool bars and the locating grippingblocks in the center drive chucking devices.

Figure IV is a diagrammatic layout showing the relation of the various parts in the power transmission and driving motor for rotating the center drive ring gears of the lathe.

Figure V is a circuit and operating diagram showing'the arrangement used when operating a tailstock with an unloading rail and a loading rail.

Figure VI is a diagrammatic layout of the op-' erating and control mechanism utilized when operating a tailstock having a single loading and unloading rail.

Figure VII is a diagrammatic circuit layout and operating diagram showing mechanism utilized for efiecting the accurate indexed stopping of the work spindle in a predetermined position in relation to the loading and unloading rail mechanism.

Figure VIII is a'diagrammatic showing of the' loading and unloading arrangement provided with one tailstock fixed and one movable, a finished work piece being shown in the chucking devices just at the completion of the machining operation and an unfinished work piece placed on the loading rail of the movable tailstock.

Figure IX is a diagrammatic showing similar toFigure VIII, but showing'the movable tailstock positioned for removing finished" work pieces from the chucking devices, the' finished workpiece being shown on the unloading rail and the unfinished workpiece shown on the loading rail. 1

Eigure X is a diagrammatic showing similar to Figure VIII showing the movable tailstock positioned' for inserting unfinished work pieces into the chucking devices; the unfinished workpiece having been just loaded from the loading rail into the chucking devices and the finished work piece on the loading rail ready for removal from the lathe.

Figure XI is a diagrammaticshowing of the loading and unloading arrangement provided with both tailstocks movable, a finished work piece being shown in the chucking devices just at the completion of the machining operation and an unfinished work piece placed on the loading rail of the right-hand movable tailstock.

Figure XII is a diagrammatic showing similar to Figure XI, showing the tailstocks moved to loading and u'nloadingposition, with thesunfinished work piece positioned ready for movement into the chucking devices and for ejecting. the finished work piecetherefrom.

Figure XIII is a diagrammatic showing similar to=Figure XI, showing the position of the work pieces after the unfinished workpiece has been inserted in the chucking devices.

The machine com-prises a base I upon which is mounted the center

drive chuck units

2 and 3 and the associated toolunits 4,. 5, and 6 in amanner as shown in Patent 2,069,107, dated January 26, 1937. In each of the

center drive units

2 and 3 are rotatably mounted the center drive. ring gears Ion suitable anti-friction bearings 8 which gears aredriven through idler gears 9 rotatably mountedon appropriate bearings in the center drive units by pinions I fixed on a drive shaft I I journaled on appropriate bearings in the

center drive units

2 and 3 and in the tool units 4 and: 5. The drive shaft II projects from. the left side of the tool unit 4 and has fixed on this end. a gear I2 which is adapted to be driven by a pinion I3 fixed on the pulley shaft I4 which is suitably journaled'in the tool units a, 5, andfi. 0n the righthand side of the tool. unit 6 is mounted themultiple V-belt driving pulley I5 which is adapted to be driven by a suitable electric motor I6 which has: a driving pulley I1 fixed on its shaft and is connected to the pulley by suitable V'-belts I8.

In the tool units 4, 5, and 6 are v slidably mounted the upper tool bars l9 and the lower tool bars 20. On the upper tool bars I9 are mounted the various cutting tools 2I, 22,. and 23 and on thelower tool bars are mounted the

cutting tools

24, 25, and 26, all of tools being adapted to completely-machine all of the line bearing portions 21, 2B, and 29 and the flange end 30 and stub. end 3|. ortions of a crankshaft W. r

. In each of the centerdrive ring gears 'I is provided chucking mechanism adapted to engage the crankshaft W to serve as the sole means for supporting and rotating said crankshaft in proper position in the lathe. This mechanism comprises a cartridge 32 fixed in the bore 33' of each of. the ring gears I which is adapted to bepositively driven by the key and which has 'a central bore 35 for receiving the work W. To one side of the axis :of rotation-of the-chuck in' theb'ore 35 is mounted the'fixed locating block-36 having-acourately machined angularly related locating surfaces 31 and'38 bearing a definite pr'edeter-. mined; relationship relative to. saidaxisof rotationwof the chuck. Substantially:diametrically opposite said loactingzblock 36 on the other side ofsaid axis is mounted an adjustable locating block-39"fixed' in a clamp 40 and having locating areas-4I and 42 similarly related to the chuck axis, when clamped on the work crankshaft W, as the surfaces 31' and 38 of the block 36. The crankshaft W is prepared for chucking in these chucks inthe ringgear 1 by having the locating notches 43 which engage the blocks 36-and notches 44 which engage the blocks39 premachined in'a predetermined relation to theaxis of rotation of the crankshaft W so that when gripped in said chucks the crankshaft will b e positively and securely held in correct centered and indexed position in said devices in a manner as disclosed in the related patents Re. 19,905, dated March 31, 1936; Re. 20,090, dated September l, 1936; 2,030,020, dated February 4,1936; and 2,106,501, dated January 25, 1938. A unique arrangement'of. these locating notches, however, is provided on the crankshaft W in that these notches are so arranged as to permit unlimited axial slidingof the crankshaft along the locating blocks 36 and 39 and other related surfaces to be subsequently described. vIn order to properly bind the crankshaft betweentthe locating blocks 36 and 39, the clamp '43, which is pivotally mounted in a socket-45 formed in the cartridge 32,. isprovided with a clamping eccentric 46 which isactuated by placing a wrench in the socket 41 to thereby force the sliding plunger-:48 againstthe abutment block 49 fixed in the cartri'dge 32 to move the clamp counterclockwise,

Figure 11, toward the crankshaft W. A spring urged plunger 50 bearing against the surface 5| of the cartridge 32 provides means for auto! matically raising the clamp 40 from the work when the eccentric is loosened.

When loading and unloading the crankshafts Win the lathe the center drive ring gears I are brought to a stop at a-definite predetermined .indexedposition by the hydraulic braking motor 52 attached to the shaft of the main driving motor I6 and the indexing plunger 53 which engages in the indexing disc 54 fixed to the gear I2 ina manner for example as fully disclosed and claimed in co-pending application Serial Number 209,026, filed May 20, 1938'.- This center :drive ring gear stopping and positioning apparatus is best shown in Figures IV and VII. The supply of fluid pressure for this hydraulic control system may be derived from the hydraulic fluid pressure pump 55 driven by an electric motor 56 which draws' fluid through the suction line 51' from the fiuid reservoir 58 and delivers the fluid under pressure through the pressure line 59. Drainage from a relief valvein the pump 55 for maintaining presture in. the line 59 is exhausted through the line 60 into the. drain line H which returns fluid-to the reservoir 58.

In the operation of the lathe whenthe main drive motor I6 is operating driving the center drive gears I during the cutting operation the hydraulic braking motor 521s also being driven by the motor shaft 62. Under'these conditions fiuid is discharged from the exhaust port 63 of the braking motor 52 through the lines 64 and 65, passes freely through the relief valve 66, through the line" 61, the solenoidoperated control valve 68,-'Which'is n'ormallyspring set in neutralpositionutat'. this time, into the dine- 59, and then valve 19 through escape through-the line '16 from line 12 since this latter line is at all times closed off at the control valve and serves only to supply fluid pressure .for opening the valve 11 to connect line 18 to the drain line 6|, which connection is normally cut-ofi by the spring set arrangement in" the valve when the pressure drops in the line 16. High pressure is maintained in the closed circulating circuit bypressure received from the pressure line 59 which passes through the speed control valve 19 which in turn discharges the high pressure fluid into the line 80 connected to said circuit at a definite relatively small volume for at all times maintaining the high pressure in the circuit and to make up for any leakage from said circuit. This discharge from the valve 19 is also utilized to rotate the hydraulic braking motor 52 at a definite slow speed for driving the electric motor 16 and the center drive ring gears 1 at slow speed preparatory to stopping said gears or when jogging them as will be described. The relief valve 56, while it at all times allows free flow between the lines 65 and 61, is so set at a pressure higher than that of the relief valve in the pump 55, or in other words than the pressure in the closed circuit, that fluid does not escape under these conditions through the bypass line 8| and into the drain line 6|.

Immediately upon disconnecting the electrical power fromthe motor the limit switch LS -l associated with the dog 83 on one of the ring gears 1 becomes effective through the usual rela'ys and contactors (not shown) when engaged by said dog 83 to cause the solenoid B of the control valve 68 to be energized, operating the valve 68 so as to close oil the line 69 and to connect line 61 to line-18. This causes the pressure to drop to substantially zero in the

lines

10, 12, 13, and because the intake volume through the port 1! of the braking motor 52, which is being driven at a high rate of speed by the momentum" of the electric motor l6 and the associated driving transmission for the center drive gears 1, is far in excess of that which can be supplied by the the line 80. Dropping the pressure in the line 16 causes the valve 11 to operate by its spring to close off the line 18 thus preventing fluid from passing through the line 61. Extremely high pressure is momentarily built up in lines 64 and 65 until the momentum in the electric motor and spindle transmission is absorbed by bypassing fluid through the high pressure relief valve 66 into the line 8|. Thedischarge through the line 8| passes through the line 15, through the check valve 14, and into the line'13 due to the suction action set up in the

lines

13, 12,and 10 by the rapid intake of the hydraulic braking motor 52. The check valve 82, which is arranged to prevent fiow from the drain line Bl to line 15, maintains the suction action through the check valve 14.

The hydraulic brakin motor 52 will continue to decelerate in bypassing fluid through the valve Gliuntil it has slowed down to a point where the volume taken into the intake port H is equal to the fluid pressure line -lines 64 and 65 that being supplied through the line 8 0 from the valve 19. The valve 66 is so set as toeffect the deceleration to this point by the time the work spindle has made about a half revolution of the work spindle or ring gears 1. After the hydraulic braking motor 52 has decelerated to the above point pressure again builds up in the

lines

10, 12, 13, and 16 and the braking motor 52 is driven at a. relatively slow speed for similarly rotating the work spindle by fluid from the line 80. Building up pressure in the line 16 again opens the valve 11 connecting line 18 to the drain line' 6|, allowing free flow of fluid through line 61 thus eliminating all back pressure at the exhaust port 63 of the braking motor 52 which would hinder the operation of said motor 52 at the predetermined slow speed.

As soon as the limit switch LS I is operated rendered in a conoperated. The limit is operated when the dog 84 cardition to .be effective when switch LS2 ried on one of the ring gears 1 engages it as the.

work spindle is rotated at the predetermined slow speed by the hydraulic ation of the limit switch LS-2, through appropriate relays and contactors (not shown), causes valve 81 to be en- 81 so as to connect 59 to the line 88 to cause the indexing plunger 53 connected to the piston 89 in the cylinder 90 to be urged against the inthe solenoid C of the control ergized to operate the 'valve dexmg disc 54. Exhaust fluid from the cylinder 50 under these conditions passes through line and into the drain line 22. The dog 84 is arranged to operate the limit switch LS2 just prior to the time when the notch in the indexing disc 54 is in position for engagement by the indexing plunger 53. Thus the plunger '53 bears against the periphery of the indexing disc after limit switch LS-2 has operated, the plunger jumping into the slot as the spindle transmission is rotated at slow speed by the braking motor 52 to instantly arrest rotation of the ring gears 1 and stop them in accurate predetermined indexed position.

The solenoid D of the valve 81 is adapted to be energized to connect the pressure line 59 to the line 9| and line 88 to the drain line SI for withdrawing the indexing plunger53 from the indexing disc 54 whenever the main driving motor I6 is energized. In order to prevent damage to the machine in the event the indexing plunger 53 would be inserted in the disc 54 before the spindle transmission had completely decelerated to the slow speed, a pressure controlled limit switch LS-3 is connected in series with the limit switch LS-2 and is operated by pressure in the through its connecting line 92 the limit switch LS2 inoperative so long as there is pressure in the lines 64 and 65 duringdeceleration of the lathe transmission, the pressure dropping to substantially zero in these lines to allow the limit switch LS'3 and LS 2 to operate only when the braking motor 52 has completely decelerated and is being driven at the predetermined slow speed from the hydraulic pump 55 as described.

On each of the tool bars 20 are mounted the T-shaped guide blocks 93, 94, and 95 by suitable bolts 98 passing through clearance holes 91 in said blocks and threaded in the tool bars. These blocks have guide surfaces 98 and 99 on their upper ends which are arranged to be in alignment with the respective surfaces 31 and38 of so as to render braking motor 52. Opersition and the tool bars I9 and 20 1 ed position of the tool worlrmay be compensated for base I by bolts I04 for movement to the axis of rotation of the center drive ring .gears .priate bearings upivotally mounted 'of' the" clamp II8a against the barrel I09. "hydraulically actuated plunger I21 connected to "the piston I28' in the cylinder I29 formed in the support I03 serves to actuate the clamp wplate I24 and the bolts I2I toefiect clamping *of the tailstock barrel by the clamp Ilfla.

- the aflxed locating blocks 36 in" the ring gears"! when the ring gearsarestopped in indexed poare in fully .Any variation of the retractbars .20 in setting the cut- 26 for properly sizing the by loosening the bolts '96. and moving the

blocks

93, 94, and 95 on retracted position.

ting tools. 24', 25, and

thetool bar 20 to bring their surfaces 98 and 99 in proper alignment with the blocks .35 in the center drive chucks.

On the base I of the lathe each side of the center drive chuck units and tool units are -mounted the automatically operated tailstocks -I00 and IOI. Since the construction and operation of these tailstocks is substantially alike, a description of the one tailstock IOI willsuflice for both. Noting particularly Figures 1- and III, the

tailstock' IOI is slidably mounted on dovetail guideways I02 on the support I03 fixed on the perpendicular I. A hydraulic cylinder I05 mounted in a bracket "I06 fixed to the base I having'its piston -I0'I..and associated piston rod I08 connected to the tailstock 'IOI serves to reciprocate the tailstock 10! on .the dovetail guideways Ii02.

'Mountedin the tailstock IOI is the tailstock barrel I09 having the'usual center IIO adapted to .::move parallelwith the axisof rotation of the center drive gear I. 'This barrel 'I09 is axially-reciprocated by a formed on the barrel and fixed on a rock shaft pinion :I II engaging a rack I'I2 II3 journaled against axial-movement in appro- II4 .in the tailstock I0I. outwardly projecting portion of the rock shaft The 3 center drive chucksand one or the other of the'rails I30 and I3I 'may be positioned so as g to be in alignmentwith the fixedlocating blocks 36 in the chucks and the blocks 93, 94, and 05 'on the tool bars when the chucks are stopped in'indexed. position. Whenso positioned either of therails I30 or I3I and the blocks in the chucks and on the tool bars form a substantially continuous track from the tailstocks past I the cutting tools and through the centerdrive chucks upon which work crankshafts 'W may he slid axially into and outof loading positionin the chucking devices "of the lathe. "To

load a crankshaft W in the lathe it is 'merely necessary to place the crankshaft with its notches 43 in engagement with-oneof the properly positioned rails I30 or '-I3I-and=push the crankshaftaxially-into the center drive chucks and tighten theclamping eccentrics-"46, no other manipulations being necessary before starting the cutting-operation. --At' the completion of the cutting operation the clamping eccentrics 4B are loosened and the crankshaft -W slid' axially out on one of the-properly alignedrails I30 or 'I3I.

The notches 43 and 44 to=be prepared on'the work-piece W must be of suchlimited size and so positioned as to have substantially *no' efiect on the ultimate balance and" necessary configuration of the crankshaft. But these notches mustibe of sufficient size and" so positioned on --'the= work to properly maintain item the rails and blocks unassisted by -'the-operator'in loading and unloading the work-in-the lathe. A

" surprising thing-has been=discovered by-the ap- I I3 has splines II5 which slidingly engagein the splined bore of the pinion IIB Mounted on. the bracket I06 is axhydraulic cylinder II'I- havinga piston -I I8 and an associated piston rod II9 having rack teeth formed thereon engaging thepinion II6 wherebyzfluid pressure actuation of the cylinder II1 efiects'movement of the tailstock barrel I09. In connection with this barrel; I09 is a clamp I Illafor locking the barrel in position when its center H0 is engaged with the end of the crankshaft W. This clamp II8a is on a' pin 'II9a fixed in the tailstock and extendsover the barrel I09 withv "an arcuate bearing surface I20 slidingly enugaging' said .barrel when unclamped. To the "opposite side of the barrel I00 from the pin II9a @are attached the tension bolts I2I which have "squared'heads I22 ate slots I23 'in the clamping plate movement with the tailstock IOI) mounted on apin-l25 fixed in the support 103. Adjusting nuts slidingly engaging appropri- I24 (for pivotally I26 on the bolts I2I provide means for properly adjusting the clamping force A 'Mounted on the tailstock IOI and movable therewith are loading and unloading rails I30 .and I3I*-having the angularly related surfaces ;I32 andI33 adapted to receive the mating sur- ":f'acesof the notches 43 of the crankshaft W. 13y moving the tailstock by appropriately actuating the cylinder I05 as will be described, the .tailstockbarrel and its-center-may be positioned coaxial with or removed from the-axis of said journaled against axial movement in the bracket I06.

plicantsin-developing'this loading and unloadingarrangement in'that it is foundthat much less effort is required to slide the crankshaft'W into and out of the center drive chucks on these notches than is requiredto similarly-manipulate a loading and -unloading crane supporting the crankshaft and rolling on an overhead rail of a character shown in Patent 1,700,721. Thus this arrangement not only eliminatesall former costly loading and unloading devices'" butalso greatly facilitates the handling of'the crankshaft W 'into and out of the lathe. Furthermore with an arrangement of this type it is unnecessary to raise or lower the crankshaft in a vertical plane thus further eliminating effort and fatigue on the part of the operator.

It is-to be further-noted that theuse of the prepared notches 43 and 44' are not "limited in their use to effect onlyefiicient-loading orunloading of work in the lathe but are also used in greatly increasing the efficiency of-- machining processes to be performed in ;'this lathe and in subsequent rnachining operations. '-In this lathe these notches are utilized for accurately supporting the crankshaft W in the center drive chucks and provide means for positively driving the crankshaft during-the cutting operation. Furthermore the notches 43'inthe webs adjacent the flange end line bearing 21 and stub endline bearing 29'ar utilizedfor indexing the crankshaft in chucking devicesofa character shown in Patent 2,030,142, dated February 11, 1936,

used in orbital lathes of a'character shown'in iPatent 1,934,530, dated November 7, 1933. These notches may also be utilized "in machines of a character shown in application Serial Number 80,204; filed May 16, 1936-, for subsequent finish =machining operations -0n the line bearings,

flange, and stub ends of the crankshaftand' are 2 also used in grinding the crank pins of the :"cranksh'afts. Thus the applicants have utilized with the tailstock IOI.

crankshaft but also to greatly simplify and improve the method of loading and unloading work in the lathe. Furthermore these notches accurately guide the crankshafts into and out of loading position so as to prevent damage to the cutting tools and to also permit said cutting tools to be stopped in retracted position much closer to the axis of the work than was possible in former lathes that were loaded and unloaded manually with the conventional loading devices cited above thus cutting down the loss of time required to traverse the tools to and from cutting position on the work and to thereby greatl increase the productive output of the machine to which this arrangement is applied. This arrangement'also reduces the cost of construction of the machine as it permits the use of much smaller diameter center drive gears to accommodate the necessary chucking devices and loading and unloading mechanism than heretofore has been provided.

There are various methods of operating this loading and unloading arrangement. One method would be to at all times have the tailstock I and its center IIn fixed and to insert and remove the crankshaft W from the right hand side of the machine. In conjunction with this arrangement eitherone loading rail I or both loading rails I30 and I3I may be utilized in connection When a single rail I 30 is used the rough crankshafts W are placed on the rail and loaded into the chuck and the finished crankshafts are shd out on the same rail and removed therefrom. This is a very satisfactory arrangementwhere the maximum saving in loading and unloading time is ofi set by'the lesser amount of equipment required in this arrangement. Where further savings are desired in the loading and unloading time when loading from one side'only of the machine two loading rails I30 and I3I are provided on the tailstock IOI upon one of which is placed the rough crankshafts W and the other to receive finished crankshafts W as they come out of the center drive chucks. Thus in this set up the rough crankshafts can be placed on one rail I3I and finished crankshafts removed from the other rail I30 while the machine is going through its cutting cycle.

Still another way of operating this arrangement is to have both tailstocks I00 and IOI movable and to provide a loading rail for each tailstock. In this instance the rail I30 of the tailstock I00 receives the finished crankshafts while the rough crankshafts are placed on the rail I 30. A unique feature in connection with this set up is that the operator may still remain at oneside of the machine lathe, it being unnecessary for him to go to the other side of the machine to unload the finished work. In operation both tailstocks withdraw from work holding position when the cutting cycle has been completed bringing their respective loading rails I30 in alignment with the chucks. The rough crankshaft W, which has previously been placed on the rail I30 for example of tail stock I III, is pushed axially to the left engaging the finished crankshaft lying un chucked in the center drive gears 1 whereby the finished crankshaft is ejected out of the gears and onto the rail I30 of the rough crank shaft is brought into chucking position. The rail I3I] on the tailstock I00 may be so constructed that as further crankshafts are while loading crankshafts in the I erations of the tailstock tailstock I00 as the line I 22,621 the notches not only to facilitate chucking of the passed into, machined, and ejected from the machine the finished crankshafts will automatically drop from this rail onto a suitable conveyor to be carried thereby to subsequent operations to be performed on the crankshafts. Thus with this method of operation the operator need only load rough crankshafts into the chucks and operate the clamping mechanism in the chucks. The number of times the operator must handle the crankshafts per given output of the machine is thus enormously reduced and it is also found that much less efiort is required to simultaneously slide two crankshafts in this loading and unloading arrangement than is required to operate a pair of loading devices as shown in Patent 2,069,- 107, dated January 26, 1937, because of the ease of sliding provided by the unique arrangement of the notches 43 and 44 on the crankshafts.

The operation and control mechanism for actuating the tailstock with one loading'and unloading rail is shown in Figure VI The control lever I34 for efiecting the various sequential op- I00 or IIII has a shaft I35 upon which are mounted suitable actuating cams I36 and I31 for effecting operation of the control valves I38 and I39 as will be described. When the control lever I34 is in the clamp position valve I38 is so actuated by the cam I 36 that fluid pressure from the pump 55 passes through line I40, the valve I38, through line HI, and into the head end of the cylinder I29 to force its piston I28 and rod I 21 against the clamping plate I24 to clamp the barrel I09 in the tailstock II when in work engaging position. Drainage from the rod end of the cylinder under these conditions returns through line I42, the valve I38 and into the drain line 6| to the reservoir 58.

After the work W has been machined the control lever is moved from the clamp position to the unclamp position whereupon valve I38 is delivered to line I42 to retract the piston I28 and rod I2I of the cylinder I29 from the clamping plate I24 to unclamp the barrel I09 from the tailstock IOI, drainage from the head end of the cylinder I29 under these conditions returning through line I4I, through the valve I38, into the drain line 6|. I

After having unclamped the tailstock'barrel I09 the control lever I34 is then movedto Load position whereupon fiuid pressure from the line I40 passes through the valve I39, the line I43,

freely through the bypass valve I44, through the line I45 into the cylinder I I! to eifect withdrawal of the barrel I09 from work engaging position, drainage from the cylinder I" under these conditions passes through the lines I 46, freely through the pressure reducing valve I 41, the line I48, freely through the bypass valve I49 into the line I 50, and through the valve I39 into the drain BI. After the cylinder III has efiected complete withdrawal of the barrel I09 and its piston and rod has stalled against a suitable stop, pressure builds up in the lines I43 and I45 causing fiuid to bypass through the valve I44, through the line I5I into the head end of the cylinder I05 moving its piston I01 and rod I08 to move the tailstock IM and its barrel I09 from alignment, with the axis of the center drive chucks and to bring the loading and unloading rail I30 into alignment with the center drive chucks. While the piston I0! is being so actuated fluid is being discharged from the cylinder I05 through the line I 52, freely through the valve I49, through the I50, the valve I39, and into the drain line 6 I.

I I40'passes through the line II'I,v freely-through the valve I49, through the line I52 :into therodend of 'thecylinder I05 thus moving the'tailstock IOI and its barrel I09 .into alignment with the axis of the center -.drive chucks. Under these conditions fluid is expelled from the head endof the cylinder I05through the lineI 5I, freely ,passing through the valve -I44 'into the line I43 and then through the valve I3B-.-into the. drain line. As soon as the tailstocklfll has moved to said aligned position the piston .II'I'I stalled by suitable abutment means, pressure builds up in the lines I52 and I50 discharging ,fiuid' through the valve I48. into line I 48 and. through the pressure reducing valve H1 is delivered intoline- I4'B- at a predetermined lower pressurefor actuating the cylinder I II to insert the center IIOof the barrel I09 in the tailstocklfll just the right pres sure to engage the work. without distortingit. Discharge from the cylinder I I1 :is-carriedbyzthe line I45, freely through the valve- I44,.,into the line I43andthrough thevalve I39 into'thedrain line BI. The work is then clamped in thechucking devices and the control lever =I34moved.to

clamp position to secure the tailstock barrel I09 as described. In. cases where both-:tailstocks I00 and NI are arranged to move, one of "the tailstocks would be moved to workengaging .position andits barrel clamped with -its center engaging the work to properly axially 'position' said workin the lathe by providing means for accu-z rately stopping the position of: the barrel .109 ofthis tailstock I00 beforeit is: clamped. Th'e tailstock- MI is then brought to work engaging position as described.

In instances where an unloading rail I30rand a loading rail III are utilized .in conjunction'with the tailstock IIH an operating circuit as shown in Figure V is utilized. The method of clamping and unclamping the tailstock barrel I09 is the same as described in Figure VI. The control le ver I34 is provided with .an Unload' positi'on :as. wellas .Load" position as in Figure VI. When in the Unload position the unloading railI30 is aligned with the center-drive chucks and when in the Load position the rail I31 is aligned with the chucks. in the Unload position fluid pressure from the line I40 passes through the valve assembly I53 into the line I 43, passing freely through the valve I44-.into the line ..I45 connected to the cylinder I I! to retract the barrel I09 from work engaging position at the completion of which movementfluid is bypassed through .line I5I into the head end of the cylinder I05 moving "its piston I01 and 7 rod I08 toretract the tailstock from aligned position to the uploading position; During-this movement fluid is discharged from therod end of the cylinder I05 through the'line I52, the valve I49, line I50, and the valve assembly I53 into the drain line: BI and also through the line I54 connected to an annular groove I55 formed midway the length of the bore of the cylinder I05 and connected through the valve assembly I'53' with the drain line BL, The piston I01 continues to move past-this annular groove I55 until it" is exposed to connection with the head and zchamz- When the control lever I34 is her .of the-cylinder :at :which time pressure-.irom the line 115i oanxescape through the line I 54 thus allowing the piston to come. toa vstop to. thus bring: the unloading rail I30iin alignment with the-center drive chucks.

When the control lever I34 is moved to Loadposition the valveassembly I53 is actuated to close offthe line I54 to again build up pressure in the head end chamber-of the cylinder I05 receivedtrom the-:l-ine -.I5I to cause the piston I'III to complete. its stroke to bring the loading rail I3I in aligned position with said chucks.

After the work has been appropriately loaded in the machinethe control lever is moved to the Normal position whereupon fluid pressure is delivered to the cylinders I05 and II] and fluid exhausted therefrom in a manner as describedin Figure VI, the line I54 being closed off and inef- 'fective-- during this operation.

Having, thus fully set forth-and described our invention .what we claim and desire to secure-by UnitedStates LettersPatent is:

1. In a lathe, one or morerotatable center driv chuck .rneans forrotati-ng said chucks, means for .stoppingsaid chucks, cutting tools'associated with said chucks, tailstocks associated with. said chucks, having centers and loading and unload. ing .rails incorporated therein,-and. means .for moving said. tailstocks relative to said chucks for alternately presenting saidcenters and said rails in alignment with said chucks.

.2. Ina lathe, one .or more-rotatable center drive chucks, means. for rotating said chucks, means for stopping. said chucks in .a definite predetermined position, cutting tools associated with said chucks, tailstocks associated with said chucks having. centers. andloading' and unloading rails incorporatedtherein,and means ,ior moving said tailstocks relativeto said chucks for presenting said centersin alignment with said chucks when said cutting tools areoperating on a workpiece in the chucks and for. presenting said loading and unloading railsinalignment with. the chucks when said chucks .are.v stopped for loading and unloading workirom said chucks.

3. In a lathe, a rotatable center drive chuck, means for rotating said chuck, means for stop- .ping said chuck in .a predetermined position, a

tailstock associated with said. chuck,-a center and a loading and unloading rail incorporated in said tailstock, means for moving said tailstock .rela- 'tive tothe axis of ,rotation of-said chuck-for alternately bringing said center or said rail in alignment with said chuck.

4. Ina lathe, a rotatable center drive chuck,

. said center in alignment-with said chuckv 5. In a lathe, a rotatable .cehter drive chuck,

means for rotating said chuck, means'ior stopping said chuck in a predetermined position, a tailstock each side of said chuck, a center and a loading rail incorporated in each of said tail-, stocks, means for moving said tailstocks relative to the axis of rotation of saidchuck for alternately bringing said centers or said railsin align-. ment with said chuck. I f

6. In a lathe, a rotatable center-drive chuck, means for rotating said .chuck,.. means for stopping said chuck in a predetermined position, a

- ing and unloading to be aligned with said tailstock each side of said chuck, a loading and unloading rail associated with one of said tailstocks, and means for moving said last mentioned tailstock relative to the axis of rotation of said chuck for alternately bringing its center or its rail in alignment with said chuck.

7. In a lathe, a rotatable center drive chuck,

means for rotating said chuck, means for stopping said chuck in a predetermined position, a tailstock each side of said chuck, a loading rail, an unloading rail, and a center associated with one of said tailstocks, and means for moving said last mentioned tailstock relative to the axis of rotation of said chuck for alternately .bringing either of its rails 01' said center in alignment with said chuck. I v

8. In a lathe, a rotatable center drive chuck, means for rotating said chuck, means for stopping said chuck in a predetermined position, fixed locating surfaces in saidchuck adapted to engage locating surfaces on a work piece to be machined in said lathe, a tailstock associated with said chuck, a center in said tailstock, a loadrail mounted on said tailstock, andmeans for moving said tailstock relative to said chuck for bringing said center in engagement with the end of said work piece in the chuck or bringing said rail in alignment with the locating surfaces in said chuckwhen stopped in said predetermined position.

9. In a lathe, a rotatable center drive chuck, means for rotating said chuck, means for stopping said chuck in a predetermined position, fixed locating surfaces in said chuck adapted to engage locating surfaces on a work piece to be machined in said lathe, tool feeding devices associated with said chuck, surfaces on said tool feedwhen said chuck is stopped and the centers of said tailstocks are removed from said work piece, said surfaces thus forming a substantially continuous rail through said chuck and past said locating surfaces in said chuck adapted to engage locating surfaces on a work piece to be machined in said lathe, tool slides operable each side of said chuck, cutting tools mounted on said slides, guide blocks mounted on said slides having surfaces adapted to be aligned with said surfaces in said chuck when said tools are retracted from said work piece and-said chucks are stopped and means for adjusting said blocks relative to said tool slides.

13. In a lathe, a pair of rotatable center drive chucks, means for rotatingsaid chucks in synchronism, means for stopping said chucks in a predetermined position, fixed locating surfaces in said chucks adapted to engage locating surfaces on a work piece to' be machined in said lathe, tool slides operable each side of and'be-' tween said chucks, cutting tools mounted on said slides, and guide blocks mounted on said slides having surfaces adapted to be aligned with said surface in said chucks when said tools are retracted from said work piece and said chucks are stopped to thus form a substantially continuous ing devices adapted to be aligned with said surfaces in said chuck when said chuck is stopped and said tool feeding devices are withdrawn from said work piece, said surfaces thus forming a substantially continuous rail through said chuck and past said tool feeding device upon which may be axially slid said work piece on its locating surfaces into or out of said chucking device.

10. In a lathe, a rotatable center drive chuck, means for rotating said chuck, means for stopping said chuck in a predetermined position, fixed locating'surfaces in said chuck adapted to engage locating surfaces on a workpiece to be machined in said lathe, tool feeding devices associated with said chuck, surfaces on said tool feeding devices adapted to be aligned with said surfaces in said chuck when said chuck is stopped and said tool feeding devices are withdrawn from said work piece, tailstocks associated with and out of said chucking 11. In a lathe, a rotatable center drive chuck, means for rotating said chuck, means for stopping said chuck in a predetermined position, fixed locating surfaces in said chuckradapted to engage locating surfaces on a work piece to be machined in said lathe, tailstocks associated with said chuck, surfaces on said tailstocks adapted surfaces in said chuck rail for accurately guiding said work pieces into or out of said chucks and past said cutting tools.

14. In a lathe a tailstock movable relative to the spindle axis of said lathe, an axially movable center in said tailstock, means for clamping said center against axial movement when engaged with a work piece in said lathe, a loading and unloading rail mounted on said tailstock, means for axially withdrawing said center from said work piece, and means for moving said tailstock to remove said center from aligned position with said spindle axis and to bring said rail in alignment therewith to facilitate loading or unloading said work piece on said axis.

15. In a lathe, a tailstock, fluid pressure means for moving said tailstock perpendicular to the spindle axis of said lathe, fluid pressure means for axially reciprocating the tailstock center, fluid pressure means for clamping said center when in work engaging position, and hydraulic control means for operating said fluid pressure means in a predetermined sequential relationship.

16. In a lathe, a tailstock, fluid pressure means for moving said tailstock perpendicular to the spindle axis of said lathe, fluid pressure means for axially reciprocating the tailstock center, fluid pressure means for clamping said center when in work engaging position. hydraulic control means for rendering said fluid pressure means operative in predetermined sequence so that the center may be unclamped and withdrawn from the work and then the tailstock moved to withdraw the center from alignment with the work spindle axis of said lathe.

, 17. In a lathe, a tailstock, fluid pressur means for moving said tailstock perpendicular to the spindleaxis of said lathe, fluid pressure means I spindle center may be unclampe'd. and withdrawn: from the work and then the tailstock moved: to withdraw the center from alignment with the work spindle axis of saidlathe, and to move said tail.- stock to a predetermined. accurate position reiative to said axis.

"18. Ina lathe, a tai1stock,l fluid pressure means for moving said tailstock perpendicular to the axis of said lathe, fluid pressure means for axially reciprocating the: tailstock center, fluid pressure means for clamping: said center when in work engaging position, hydraulic control means for rendering said fluid pressure .means operative in predetermined sequence so that the center may be unclamped and withdrawn from the work and then the tailstock moved towithdraw the center from alignment with the work spindle axis of said lathe,.and to move said tailstock to a plurality of. predetermined accurate positions relative to said axis.

19. In a device for loading and unloading rough, irregular work pieces in a machine tool, a loading and unloading rail associated with a chucking device of said machine tool adapted to engage locating surfaces premachined on said work piecesto be machined sothat said work pieces may be slid axially on said surfaces on said loading and unloading rail into or'out' of said chucking device, means for positioning said. chuckin device in a predetermined position relative to said rail. and means in said chucking devicefor gripping said work pieces by means of said surfaces.

20. In a device for loading andunloading rough, irregular work pieces in a center drive lathe; a loading and unloading rail associated with achucking device of said lathe adapted to en-' gage locating surfaces premachined' on said work pieces to be machined so that'said work piece may be moved axially on said surfaces on said loading and unloading rail into or out of the. center drive chucking device of said. lathe, means for positioning said chucking device in a predetermined position relative to-said rail, and means in said chuckingdevice for gripping said work pieces by means of said surfaces.

21. In a device'for loading and unloading rough, irregular workpieces. in a center drive lathe, a loading rail associated with a center drive chuck- 8. device f S d lathe adapted to engage 1ocating surfaces premachined on said work piecesto be machinedso that said workpieces may be moved axially on said surfaces on said loading rail into the center drive chucking device, means for positioning said. chucking device in a predetermined positionrelative to said rail, means in said chucking device for gripping said work pieces by means of said surfaces, an unloading rail associated with said chucking device adaptedv to engage said locating surfaces on the work pieces when it is moved out of said chuckin device after the completion of said machining.

22. In a device for loading and unloading rough, irregular work pieces in a center drive lathe, a loading rail located to one side of a center. drive chucking device of said lathe adapted toengage locating surfaces premachined on said work pieces to be machined so that said work pieces may be moved axially on said surfaces on said loading rail into said center drive chucking device, means for positioning said chucking: device in a predetermined position relative to said rail, means in said chucking device for gripping said work pieces by means of said surfaces, and an unloading rail located on the other side of said chucking device adapted to engage said locating surfaces on the work pieces: when it is moved out of said chucking: device after the completionfof said machining.

' 23-. Ina loading andunloading mechanism for a center drive crankshaft lathe, a loading rail associated with a center drive chucking device of said lathe adapted to engage" locating surfacespremachined onwebs of a crankshaft to be machined so-that said crankshaft maybe: moved axially on said surfaces on said loading. rail into the center driveichucking device, means for positioningsaid chucking. device in a predetermined position. relativestm said: rail, m'eans'in said'chucking'. device: for grippin saidcrankshaft by means of said: surfaces, and? an unloading rail associated' with said chucking device adapted to en gage saidi'locating'. surfaces of the crankshaft when. it is moved out of said chucking device after the completion of said machining.

. 24-. Inzaloading andiunloadingmechanismzfor a. center drive crankshaft lathe, a loading rail located toone side of a center drive chuckin device of sai'di'lath'e adaptedito' engage locating surfaces premachined on webs of a; crankshaft to be machinedso that said crankshaft may' be moved: axially on said surfaces on: said loading railinto the center drive chucking device, means for positioning sald' chucking device in a predetermined position relative to said rail; means in'i said chucking device: for gripping said crank"- shaft by meansof said surfaces,'and a? ing: riail located at the" other side: of sa 6; chucking device adapted: to engage said: locating surfaces on the crankshaft when his moved out of saidchucking;devicev after-the completion of said machining. I

25; Ina loading and unloading mechanism for a center drive crankshaft lathe, a loading rail arranged to be positioned in alignment with the center: drive chuck ofxsaid' lathe. adapted to engage locating" surfaces" premachined on webs of a crankshaft-tube machined s'o'that said crank shaft. may be'moved' axially onv said surfaces on said loading'railintosaid chuckymeans for posi tioning said. chucking device in a predetermined position: relative to said. rail, means in said chucking device p g: said crankshaft by means of said surfaces, and an unloading railarranged-tobe; positioned in alignmentwiththe center drive chuck toengage: said locating cur-- facescn the crankshaft whenit is moved out of said chucking device after the" completionof said. machining.

26:. In a loading; and unloading mechanism for.

a. center drive crankshaft lathe, means f'or posttioning a loading rail in alignment with a chuck ing device of said lathe; said rail being adapted td slidably support a: crankshaft having prer'nachined locating surfaces thereon and adapted to: be placed. on-said rail on said surfaces and moved. into said chucking device, means in saidchucking devicefor gripping said crankshaftby means of. said' surfaces, and means for positioni'n'g an unloading railin alignment with said chucking: device-to receive said" crankshaft whenmachined as it is ejected from said chucking device by moving: further unmachined crankshafts from said loading. rail into saidchuckingdevice.

2"7. In a loading and unloading mechanism for a: center drive lathe, a center d'i'ive'chuck' having" meansadapted to grip a crankshaftby means of locating surfaces' in predetermined-position thereon, means for positioning said chuck in predetermined posltion of rotation, means on one side of unloadand aligned with said gripping means on said chuck when the latter is insaid position, for guidan unworked crankshaft into on, and Work supporting means each side of said chuck and aligned with said gripping means of said chuck adapted to permit sliding of unmachined crankshafts axially of said chuck to engage finished crankshafts gripped in said chuck, said .means permitting continued axial movement of said shafts as said unfinished crank'shafts are brought intosaid chuck.

t 29. 'In a lathe, a tailstock movable relative to I thespindle axis of said lathe, an axially movable center in said tailstock, means for clamping said center against. axial movement when engaged with a work piece in said lathe, a loading and unloading rail connected to said tailstock, means for, axially withdrawing said center from said work piece, and meansior moving said tailstock toremove said center from aligned position with said spindle axis and'to bring saidrail in alignment therewith to facilitate loading or unloading said work piece on said axis.

30. In a lathe, a tailstock movable relative to the spindle: axis ofsaid lathe, an axially movable center in'said' tailstock, means for clamping said center against axialmovement when engaged with a-work piece in said lathe, a loading and un-' loading rail associated with said tailstock, means for axially withdrawing said center from said workpiece, and means for moving said tailstock to remove said center from aligned position with said spindle axis and to bring said rail in alignment therewithto facilitate loading or unloading said work piece on said axis;

31. In, the lathe, a bed, a" tailstock-having an axially movable center and mounted on said bed for motion transverse to the'axis of said center, fluid pressure operating means for so moving said tailstock, a binder for said center, fluid pressure actuating means for said binder, fluid pressure power'means foraxiallymoving said center,- a control member for said power meansand said operating means, and connections including a manually-controlled element for actuating said power means, said actuating means and said operating means, to release-said binder and to re tract said center and movesaid tailstock on continued motion of said element in center releasing direction, after release has been effected, and to return said tailstock, advance said center and then lock it on movement of said actuating means to its initial position.-

- 32. In a lathe, a bed, a tailstock having an axially movable center and mounted on said bed for motion transverse to the axis of said center, fluid pressure operating means for so moving said tailstock, a binder for said center, fluid pressure actuating meansfor said binder, a handlehaving a plurality of operative positions, fluid pressure guidance of said surfaces, by-

unfinished crankshafts to thereby, simultaneously eject said finished crank-' power means for axially moving said center, control means for said power means, said operating means and said actuating means, and connections between said handle and said control means for actuating said control means to cause said power means to retract said center and move said tailstock when said handle is moved from a first position through a second position to a third position and to return said tailstock and presentsaid center to the work when said handle is moved from said third position to said first position, and to efiect operation of said actuating means for operating said binder to clamp and unclamp said center when said handle is moved from said first position to said second position. v

33. In a lathe, a bed, a tailstock having an axially movable center and mounted on said bed for motion transverse to the axis of said center, fluid pressure operating means for so moving said tailstock, a binder for said center, fluid pressure actuating means for said binder including a handle having a plurality of operative positions, fluid pressure power means for moving said center, a control means and said operating means, and connections between said actuating means and said con trol member for actuating said power means to retract said center and said operating means to withdraw said tailstockwhen said handle is moved from a first position through a second position to a third position and to return said tailstock and present said'center to the work when said handle v and means for moving said tailstock transversely 1 binder to be released,

of the lathe to permit one of said rails to come into alignment with the axis of rotation of the lathe in order to receive said workpiece from the lathe while holding another workpiece in a second rail in readiness to be moved further with the tailstock into line with said axis of rotation and preparatory to locating the second workpiece in machining position in the lathe When'the first workpiece has been removed therefrom. 35. In a lathe, a bed, a tailstock movable'transversely of the bed and carrying an axially'movable center, a binder for said center, first fluid pressure means for operating said binder, second fluid pressure means'for moving said tailstock, and third fluid pressure means for moving said center, a control element for said first, second and third means, adapted to be moved to a, plurality of positions, said element in one position being adapted.to operate said first means to cause the and then to operate said second and third means to retract said center and move the tailstock from the axis of rotation of the lathe on continued motion of said element after a release has been effected, and on further movement of said element to operate said second and third means to move the tailstock into the axis of rotation of the lathe and to cause the center to contact the workpiece, and on still further movement of the element, to operate said first means to'clampthe binder about the center. 7 WILLIAM F. GROENE.

WALTER R. MEYER.

member for said power