US2424153A

US2424153A - Connecting and positioning device

Info

Publication number: US2424153A
Application number: US485980A
Authority: US
Inventors: Myron S Curtis; Schoepe Harry
Original assignee: Warner and Swasey Co
Current assignee: Warner and Swasey Co
Priority date: 1943-05-07
Filing date: 1943-05-07
Publication date: 1947-07-15
Anticipated expiration: 1964-07-15

Description

f M. s. CURTIS r-:T Al. 2,424,153

CONNECTING AND POSITIONNG DEVICE Filed May 7,` 1943 July 15, 1947.

'YISheets-Sheet 1 Mme/v .S Caer/.s HARRY .5C/#05,05

BY ya am July l5, 1947. M. s. CURTIS ET Al.l 2,424,153

CONNECTNG AND POSITIONING DEVICE lNvENTloRs. MY'Ro/Y .52 Cams July l5, 1947. E M. s. CURTIS ET Al. 2,424,153

CONNECTING AND POSITIONING DEVICE Filed May 7, 1943 '7 Sheets-Sheet 3 July.15, 1947.

M. S. CURTIS ET AL CONNECTING AND PosITIoNING DEVICE Fired May 7, 1945 7 sheets-sheet 4 INVENTORS,

Mmc/v .5T Caer/s Jrfxly 15, 1947. M. s. CUR-ns ET AL 2,424,153

CONNECTING AND POSITIONING DEVICE July 15, 1947. M. s. CUR-ns ET A1. 2,424,153

CONNECTING AND POSITIONING DEVICE Filed May 7, 1943 7 Sheets-Sheet 6 if?. Z5

July 15, 1947. M. s. CURTIS ET AL 2,424,153

CONNECTING AND POSITIONING DEVICE Filed May '7, 1945 '7 Sheets-Sheet '7 IN VEN TOM Patented July 15, '194 CONNEC'IING. AND1` P0 SITIONING.. DEVICE MyronS. Curtis and Harry Schoepe, Cleveland,

Ohio, assignors to The Warner &. Swasey Company, Cleveland; Ohio, a corporation of Ohio Application ll/Iafy:` 7, v194:3, .SerialNm 485,980

(Cl. 19g- 139) ZZICIainis.

1. This invention relates to a connectingv and positioning device arranged between a driving member and a movable element and said dev-ice.

functions Witha positive driving action tomove. said element.

One of the important objects of the invention isV to provide a device of the character specied: and which is so constructed that the movable element can be disconnected from the driving member and stopped always in the same predetermined denite position.

Another object is to provide a device'of the character specified which is so constructed that said deviceafter connecting the movable element With the driving member remains in this condition to give said element apredetermined move'- ment and then automatically functions to` disc-onnect said element and member and stop the. (glement alvvays in the same predetermined posiion.

Anotherl important object is to providera device ofthe character specied and which device does not employ the structure usually present. in.

clutch mechanisms but is constructed in such' a manner that the connection and disconnection of the drivingmember and the movable element-v results in a predetermined acceleration and decelerationV oi the movementof said element .and causes the latter to stop or start. its movement upon disconnectionv or connection .gradually'and smoothly and Without a hammerblow effect.

A further object is to provide a device ofv the character specified and which device is particularly useful in a machine tool structure foraactuating the feeding, mechanism of a slide-or similar element to successively impart to such slide or element a predetermined feeding movement vand to stop such movement of the sldeor element repeatedly in the same definite position.

Another object is to provide a device ofI the character specified for use in a machine tool to obviate the employment therein of positive stops for terminating the feeding'movementsof slides or other elements of the machine tool atthe exact end of a machining operation.

A still further. object is to provide a device .of the. character specified and which device when utilized in a machine tool in the drive train to a toolor` Work carrying slide eliminates.` the. necessity of they operator manually completing the; feeding movement of the slide at the. end of a machining operation.

Further and additional objects` and advantages:

noty hereinbefcre specied Will become apparenti 2A. duringj the-detaileddescription which is to.. follow. of several embodiments of the invention.

Referring to the accompanying drawings,

Fig.. 1 is a iront .elevational View cfa machine tool, .in this instance a lathe,.and wherein there. is-included a. device embodying. the present invention and. vvl'iichy used for connectingthe actuating mechanism of a mainslide to adriving. source. andfor stop., ping andpositioningthe. slide in.predetermined positions.

Eig. 2. is. a-diagramrnatic view partly in-.el'evation.. andpartly in sectionshowing the slide-the actuating mechanism therefor and.. the. device embodying the invention associated. with said mechanism.

Fig. 3 is a vertical sectional view through a portion otheslide actuating mechanismshovvn in Fig. 2.and through' theconnecting and positionin g. device.

Fig. 4 is a detached .elevationalview takensubf stantially from the line .li-lof Fig. y3,1 ookingin the direction of the arrowswith certainportions ofthe device shown in section.

Figs. 5, 6 and. 7 are sectional views tak'enre'- spectively. alonglines 5 5, .li-.45" and T -T of Fig. 4, looking. in the directionof the arrows,

Fig. 8`is a View similar to Fig. 3 but With. certain of the parts of the .connecting and'pgositioning device disposed 4in adiffer'ent relationship.'

Fig. 9' isan elevationalvietv takensubstantially fromline 9-9, ofl Fig. 8,.loroking in the direction ofthe arrows', with certain portions of' the device shown in section.

Figs. 10 and 1l areideveloped views ofthe cir'- Cumierenceof. the shiftable cam member of the device with the pins shown in section; Figi. 10 illustrating'the relationship of theparts as dis'- closed inFgs. 3'and;.4 ;while Fig. 11 discloses the relationship of the partsl as illustrated in Figs. Sand 9.

Fig. .12 is a diagrammatic view, partlyfin" eleva'- tOII-arid-Dlltly in SGQGOH, and iS Smi1ar`tOTFg 2 butv illustrates a mo'diiied form off' connecting.v and'positioning device fromthatshovvn'in Fig. 2, it 'being' notedth'atthe device shown in Fig, 2 iswa single acting device functioningautomatically to position the slide 'at' the, end of"its 'movefment in one direction only, While the device'sliown' in Fig. 12 is a double .acting device functioning automatically to position-the slideat-the endof its movement-'in both -cli-rections.I

Fig. 13'- is `a view-A similar` to Fig.. .3 ibut-illustratingftne connectingaand positioning. deviceshovvn 55.' 1n Fig. .12.

by Way of. example may be.

Fig. 14 is an elevational view taken substantially from line lE-Ili of Fig. 13, looking in the direction of the arrows, with certain of the parts shown in section.

Figs. 15, 16 and 17 are sectional views taken, respectively, along lines l -l5, lS-l and l'l-i'l of Fig. 14, looking in the direction of the arrows.

Fig. 18 is a view similar to Fig. 13 but illustrating a different relationship between the parts than that shown in Fig. 13.

Fig. 19 is an elevational view taken substantially from line lil- I9 of Fig. 18, looking in the direction of the arrows, with certain of the parts shown in section.

Fig. 20 is a view similar to Figs. 13 and 18 but showing a still dierent relationship between the parts of the device than those shown in said Figs. 13 and 18.

Fig. 21 is an elevational view taken substantially from line 2l-2l of Fig. 20, looking in the direction of the arrows, with certain of the parts shown in section.A

Figs. 22 and 23 are developed views of the circumferenence of the driven cam member of the device shown in Fig. l2 with the pins shown in section and the parts corresponding in relationship as shown in Figs. 13 and 14, with the driving pin in driving relationship; Fig. 22 showing the cam member being driven in one direction while Fig. 23 illustrates said member as driven in the opposite direction.

Fig. 24 is a developed view of the circumference of the driven cam member of the device shown in Fig. 12 and corresponds to the position of the parts as shown in Figs. 18 and 19.

Fig. 25 is also a developed View of the circumference of the driven cam member of the device shown in Fig. 12 with the parts corresponding in relationship t0 that shown in Figs. 20 and 21.

Fig. 26 is a diagrammatic View showing the way in which a preferred curvature may be developed for lthe cam groove.

of a modified form of track system.

The connecting and positioning device of the present invention can be employed advantageously in various types of machines wherein it is desired to connect a driving member with a movable element of the machine to move the same and then tov automatically disconnect the member and element and stop the movement of the element 'repeatedly in the same predetermined position or positions. Inasmuch as the device has particular utility when used in a machine tool to connect the actuating mechanism of a slide or other movable element of the machine tool with a, driving source, the device is illustrated and described herein as employed in that relationship, it being understood, however, that this is merely by way of illustration and not by way of limitation.

Heretofore mechanical drives to a movable element of a machine have had the disadvantage that the element does not always come to a stop repeatedly in the same position or location each time the drive is interrupted due to the varying velocities of the members of the drive vand also to dilferent friction and load factors to which said members are subjected.

This disadvantage is particularly serious in machine tools where it is desired to stop the feeding `movement of a slide which carries the Work or a cutting tool repeatedly in a definite predetermined position in order-.that the workpiece may be accurately machined within close tolerances, as for example to stop the movement of a slide actuated by a screw and nut mechanism. Heretofore it has been necessary to employ positive stops in the form of stop rolls for positively and accurately locating the tool or work carrying slide at the end of thermachining operation. Ordinarily the power feed drive to the slide is released just prior to the completion of the machining operation and then the operator by means of the hand wheel manually moves the slide into contact with the positive stop to properly position the slide and complete the machining operation.

' v'lhe manual operation of the slide by the operator is objectionable since the operator cannot always apply the same degree of force in moving the slide against the positive stop and the result is the work piece may not be machined within the close tolerance called for due to the variations in pressure exerted on the slide by the operator.

The connecting and positioning device embodying the present invention does away with the necessity of using the positive stops for the work or tool holding slide of a machine tool since said devicefunctions automatically to stop the movement of the slide repeatedly in exactly the same location .for the same tool setup and thus the work piece is machined within the close tolerance limits demanded at the present time.

The use of the device of the present invention in a machine tool also eliminates the requirement that the operator manually move Jthe work or tool slide against the positive stop above referred to and thus increases the efficient operation of the machine and the accurate machining of the work pieces within close tolerance limits,

Inasmuch as it is preferable, particularly for high operating speeds, to provide gradual and smooth acceleration and deceleration of the movable element in order to avoid any hammer blow elTects in the starting and stopping of said elements, an important aspect of the invention is the arrangement employed for such purpose and which will later be fully explained.

' As previously stated, the connecting and positioning device of the present invention is illustrated herein, by way of example, as applied to a machine tool in this instance a lathe. The lathe Y is shown in Fig. l and comprises a headstock 30 having a rotatable work spindle 3|. The bed of the lathe is provided with ways for a main slide 32 and a cross slide carriage 33 which supports a crossslide 34 as is well understood in the art. The spindle 3l may be driven at different speeds by a suitable variable speed transmission not shown ,as it is well known. The spindle 3l is operatively connected through suitable gearing or other means to a shaft 35 (see Fig. 2) carried by a gear box 3b mounted on the front of the machine.V The shaft 35 has xe'd thereto a, gear 31 which meshes with a gear 38 formed on a clutch member 39 freely rotatable on a shaft 4D extending alongy the front of the bed of the lathe and in this' instance through the apron of the cross slide carriage and intoa gear box 4l secured to the end of the bed, as clearly indicated in Fig. l. A shaft 524also carried b y the gear box 36, has a gear d3 fixed thereto which meshes with a gear 44 formed on a clutch member 45 also freely rotatable on the shaft lill. The shaft 42 is driven by a suitable power source, not shown, at a relatively higher speed than is the shaft 35 and functions to drive the shaft d during the idle movements of the main slide 32. A shiftable clutch member lis splined on the shaft 4l! interme-V ldiate the clutch members-39 and 45 andcanbe :sleeve-like portion 59 is provided with a 'boss 5l having a radially'extending bore into -which a cup-s'hapedmember 52 is screwed. A plunger 53 Lis slidably mounted inthe cup-shaped member-52 and is normally urged in a radially inward direction by a spring 54. The -rgear'lil is freelyfrotatable on a stationarysshaftli mounted in 'the gear box '4i and extending parallelto the shaft 49.

It will be noted that the gear `Iii) is mounted on a reduced portion of the shaft 55 and is held against endwise movement by the shoulder of the shaft 55 formed by the reduced portion and by the bearing boss for the shaft formed internally of the gear box'lli. The shaft 55 also carries a second freely rotatable gear which is provided with an'elongated hub portion -51 that extends into the sleeve-like portion 59 Aof the geardg. Thepurpose of the elongated hub portion 51 extending into the sleeve-like portion Y5l! and the other parts associated therewith will subsequently be explained.

The gear 56 and hub portion 51 are slidable axially of the shaft 55 as well as being freely rotatable ythereon and said gear meshes with an elongated gear 58 fixed to a shaft 59 rotatably supported in the gear boxv 4I andextending outwardly therefrom `along the bed and toward the headstock. The shaft 59 is threaded for a portion of its length as indicated at 60 and constitutes the actuating screw for the main slidef32. The main slide 32 is provided in this instance with a depending nut 5l which receives the threaded portion 60 of the shaft 59 and causes said shaft when rotating to impart linear movement to the slide 32 in either direction depending upon the direction of rotation of the shaft. f

The hub 51 is `provided with a track system shown, in this instance, as spaced annular grooves 62 and E3 and these groovesare connected with camming portions in the form of a curved groove 54 having a straight walled driving and stopping portion indicated at E5 and parallel to the axis of the hub,see Figs. 4 andi() and located midway rbetween the grooves 52 land 63. Of course the camming portions of the track system could be other than curved portions, as for instance they might be straight portions angularly disposed to the annular portions. The major^seg ments of the

annular grooves

92 and 63 are of uniform depth and correspond in vdepth to the depth of tne curved groove 5d. However, the remaining segments'of the

grooves

62 and 63 are of varying depth and rdecrease in depth toward the points where the curved. groove 64 merges with the annular groovesZ and-53,.as clearly shown in Figs. 3I 4, 5 and 7.

The plunger 53' carried by Vthe sleeve portion inthe `drawings,'that is in or to the right ofthe d straight'walled portion 6510i said curved groove for a purpose later to be explained.

The 1. gear i' box= 4 I is' provided rinteri'orly 'with a supporting :bracket inwhich is sli'dably mounted -a jplunger #formed of ytwo interconnected :parts fii '"and61, with the latter-'part having a shouldere'dextended Vportion '58 passing into a recess -inthe l part '5B ian'd engaging 1a Ispring-69 located inv'said "recess, .wherefore the part l :can have movement relative to the part 61, butfnormally said part/@66 and 61 willmovetogetheras Vaunit.

The part of the two partplunger is l'adapted to .extend into and 'travel in the;annular lgroove 62 andithe left hand portion ofthe curved-groove vlillup-to and including the straight walledportion 65 thereof Vfor a purpose later'to be explained. `The part '61 of "the two partplunger is provided nearitsouterend with a slot which receives'the rounded "free end of one arrnof 'a bell vcrank lever 19 that is 'rockably mountedrin the :gear box-AI. vThe free end ofthe other arm ofcsai'd -'bell'crank lever 19 is pivotally connectedztoy a link 1l `which extends outwardly of the gear box'M and has 'its zouter end pivotallyconnected tov the free'end Vof'one larm of `a bell crank-lever 12` which latter lever is `rockably supported by a bracket von the bed ofthe machine,- see Fig. .2. The free end of the other arm yofthe bell crank lever 12-is of roun'ded'formati'onand is located in a slot formed in the `enlarged ylower-"end of Va cam rod 13 which carries a collar "1li toflimit its -upward. movement, and'said rod extends into/a cup-shaped housing`15 carried fby the bed. 'The rod 13n at its upper end is provided'fwith an enlarged portion v19 'which'fsli-dably iitsl'the cups'hape'd-'housin-g 4and has its outer Sor'y free end f `tapered or beveled formation `as clearlyindicated inFig. 2. A spring 111 located in the housing f15 *surrounds the rod v1.3 *between fthe 'base `of the housing and the renlarged portion'16 ofthe rod and normally maintainsssaid rod in its uppermost position, with the collar 14 abutting the lower end of the housing 15.

The slide 32 is provided `in its side with an elongated T-slot 18 and a cam lug`19 is adjustably supported by said slot 18 randfcan be clamped in various adjustedpositionstherein. The cam lug 19 is provided on one side with 'a beveled surface 89 that cooperates with the beveled end of the enlarged portion 1S of thecam rod 13 when the slide 32 is moving in a forward-or feeding direction. The cam lug 19 is positioned inthe slot 1B in accordance with the length of feeding movement to be imparted to the slide 32 andthe location of said cam lug determinesthepositionin which the feedingA movement of said slide is to be stopped.

It will be understoodlthat as the slide 32 is moved forwardly in `a feeding direction by the screwA til the beveled surface'f ofthe lug 19 will contact the beveled upper end vofthe cam rodv13 and depress said rod againstthe action of the spring 11. This depression ofthe .cam rod 13 will be transmitted through the bell crank lever 12, link 1|, and bell crank lever 1,9 to the two part plunger 65,51 to move the same radially vinward for a purposel later to4 be explained.

However, it should benoted that except when the cam rod 13 isdepressed I'by-'the cam lug 19 the two part plunger 96,151 is inthe position shown in Fig. 3, at which time the yinner end of the plunger extends slightly into the annular groove52 for al distance less than the minimum depth of saidgroove. The purpose of this normal or inactive 4arrangement is '1 to have: theplunger aigues 'r hold the hub 51 and gear 56 against axial shifting movement.

Assuming that the slide 32 is having feeding movement imparted thereto by the screw B and that the shi-ftable clutch member 46 is in engagement with the clutch element 39 and the shaft 40 and gears 48 and 49 are rotating to impart rotation to the shaft 59 through the device already described, the parts of said device will be in the relative positions indicated in Figs. 2, 3, 4 and 10. At this time the driving plunger or element 53 carried by the sleeve portion 5l] of the gear 49 will be located in the straight walled driving and stopping portion or section 55 of the curved groove 64 of the hub 51 (see Figs. 4 and 10) and will be engaged on diametrically opposite sides by the straight walls of said portion 65. Therefore the forward rotation of the sleeve portion U will cause the plunger 53 to move in a circular path as indicated by the arrows 53a of Figs, 4 and 10 and this movement of the plunger 53 at right angles to the straight walls of the portion 65 of the groove 64 will impart rotary movement to the hub 51 in the direction indicated by the arrow 51a, with a resultant rotation of the gears 56 and 53 and the screw 60 to move the slide 32 in a forward or feeding direction.

Y It will be noted that the location of the drive plunger 53 in the straight walled portion 65 of the curved groove 64 while driving, as just referred to, has no tendency to cause axial shifting movement to the hub 51. Furthermore, at this time the two-part plunger kH55, 61 extends slightly into the annular groove 62 (see Fig. 3) and suiiiciently to hold the hub 51 positively against axial shifting movement. This is the normal inactive position of the two-part plunger 55, 61 and in such position said plunger in no way interferes with the free rotation of the hub 51 as previously explained.

It will be observed that when the drive plunger 53 is in the position just explained and is driving the hub 51 a positive uninterrupted timed relation drive exists between the work spindleA 3| and the screw Si) and the main slide 52 thus asn suring the desired feeding rate for said slide and the work or tools carried thereby. The slide continues its feeding movement until the beveled surface Sil of the cam lug 19 engages the beveled upper end oi the cam rod 13 and depresses said rod to cause the two-part plunger El to be moved radially inwardly of the groove 62. This movement of the two-part plunger radially inwardly of the groove 52 results in the inner end of the plunger following or riding into the left hand section of the curved groove 55 as the hub 51 rotates and as indicated by dash lines in Fig. 1l. The inner end of the two-part plunger riding into the curved groove 55, as just referred to, effects an axial shifting movement of the hub 5'? toward the left, as viewed in the drawing, with a resultant relative movement of the driving l plunger 53 out of the straight walled section 65 of the curved groove 54 and into the right hand curved section of said latter groove, as indicated by dash lines in Fig. 1l. As soon as said drivingV plunger has moved out of the straight walled section 55 of the curved groove said plunger Y pressed against the spring 54 as the plunger rides over the high point of the groove 63. By the time that the driving plunger 53 has traveled through the right hand section of the curved groove Gli and into the annular groove `65 the hub 51 has been shifted axially so that the two-part plunger 66, 61 will have completed its travel through the left hand section of the curved groove and will have its inner end located in the straight walled driving and stopping section or portion 55 thereofY and will have brought the rotation of the hub portion 51 to a positive stop and the parts will be in the position indicated in Figs. 8, 9 and ll. The arrangement of the plungers and the annular grooves is such that if either plunger is in th-e straight walled driving and stopping section or portion 6510i the curved groove the other plunger will be in its respective annular groove.

It will be seen that the positioning of the twopart plunger 55, 61 in the straight walled section 55 definitely and positiv-ely stops the rotation of the hub 51, gears 55, 53, shaft 59 and screw G, with a resultant stoppage of the feeding mcvement of the slide 32 and the location of the latter in a predetermined deiinite position which will always be the same for each feeding movement during the same adjustment of the cam lug l5. It will later be explained that the curvature of the groove 61% on both sides of the straight walled section 55 is such that the movement of the plunger 66, 51 into the groove eifects a gradual smooth deceleration in the speed of rotation of the hub 51 and brings the latter to a stop without a hammer blow effect.

The feeding movement of the slide 32 has now stopped, but the shaft 35, gears is and i5 and sleeve 56 continue to rotate with the plunger 53 traveling idly around in the groove, 53. The operator in order to bring the slide back to its rearrnost position moves the shiftable clutch element by the control lever il out oi engagement with the clutch member 39 and into engagement with the clutch member 125, whereupon the shaft siii is rotated in the reverse direction by the shaft t2 through the gears i3 and it and at a faster rate of speed than when it was rotating in the forward feeding direction. The gear i9 and sleeve 55 now start to rotate in the reverse direction, whereupon the driving plunger 53 traveling in a direction opposite to the arrow 53o sho-wn in Fig. 11 enters the right hand section of the curved groove 64 in the hub 5l, as indicated by dash lines in Fig. l1. As the driving plunger 53 travels in the right hand section of the curved groove 6ft toward the straight walled section 65 theremF it shifts the hub 51 axially toward the right as viewed in the drawing and at the same time the two-part plunger 56, 51 moves out of the straight walled section 55 and travels in the left hand curved section of the groove 54 until it is in the annular groove 52 as indicated by dash lines in Fig. il. The instant that the stopping two-part plunger 66, 61 moves out ofthe straight walled section 55 of the curved groove the hub 51 commences to rotate and accelerate under the action of the driving plunger 53. During this accelerating rotation of the hub 51 the driving plunger 53 moves into the straight wall section 65 of the groove 65 without a hammer blow effect since the acceleration of the hub 51 has brought the latter into synchronized rotation with the sleeve 50. As soon as the hub 51 commences its rotation in the reverse direction the screw t'rotates in the reverse direction and the slide 32 commences to move rearwardly. This rearward movement of the slide causes the beveled surface Se of the cam lug 'i9 to move out of cooperative engagement with the beveled upper end of the cam ro-d le to allow the spring il to move said rod upwardly and torestore the two part plunger et, el to its normal inactive position as indicated in 3, wherein it is just slightly engaged in the groove 62 to prevent axial shifting movement of the hub 51 while the hub is rotating in the reversedirection. In case the two-part plunger has traveled out of the curved groove ed and into the annular groove S2 before the cam lug 'i9 is completely out of engagement with the beveled end of the cam rod '13 then for one or more turns of the hub 5l in the reverse direction the part @e of the plunger will be compressed against the spring ed and telescope relative to the shouldered portion t8 of the part 6l of the plunger each time the end of the plunger contacts the minimum depth segment of the groove. The operator allows the rearward movement of the slide to continue until the cutting tools have cleared the work sufficiently to allow the latter to be removed and a new work piece loaded in the worxy holder, whereupon the operator by means of the control lever il shifts the movable clutch element 4?, into neutral position and terminates the rotation of the shaft and stops the rearward movement of the slide 32.

It will be understood that when the rotation of the shaft iii stops, as just explained, the sleeve portion 5d of the gear 49 and the hub 5l also stop rotation with the driving plunger 53 located in the straight walled section 65 of the groove and with the two-part stopping plunger BS, El extending into the annular groove 62, as shown in Figs. 3, l and l0. When the operator has loaded a new work piece into the workk holder he can again cause forward feeding movement to be imparted to the slide 32 to machine such new work piece. He accomplishes this by shifting the control lever il to move the shiftable clutch element 46 into engagement with the clutch element 39 and start the rotation of the shaftV 40 in the forward direction. Immediately the sleeve portion E rotates in th'e forward direction and thedriving element or plunger 53 drives or rotates the hub El in a forward direction with a resultant forward rotation of the screw t@ anda forward feeding movement of the slide 32. The forward movement of the slide 32 continues until the cam lug i9 again depresses the cam rod "i3, which action as explained above, causes the driving plunger 53 to moveout of the curved slot and into the annular slot 63, while the holding plunger E5, 6l moves out of the annular slot 62 into the curved slot 64 and comes to rest in the straight walled section @5 thereof to positively stop the rotation of the hub 5l and the feeding movement of the screw @D and the slide in exactly the same position that the slide was stopped in as previously explained.

It will be seen that the slide may have-feeding movement imparted thereto time after time and will always be stopped upon completion of its feeding movement in th'e same predetermined position.

It will be recalled that the two-part holding plunger 65, 6'! is slidably supported in a bore formed in a fixed bracket portion interiorly of the gear box ill, and, therefore, said plunger cannot be displaced circumferentially of the hub 5l and when said plunger engages in the straight walled section 65 of the groove 64 it will positively stop the rotation of the hub 51 in exactly the same position each time the cam rod 13 is depressed by the cam lug was the slide reaches the end of its feeding movement'. Consequently, since the gears 56, ESthe screw fand the slide 3'2, constitute an unbroken drive train, they will all be decelerated and then stopped and locked repeatedly in exactly the same position each time the plunger E55, el has engaged in the straight walled section of the groove Be of the hub 51 without allowing any further rotation or coasting ofthe parts. Therefore the feeding movement of the slide 32 will be terminated and the slide located in exactly the same position at the end of each feeding movement and the tools carried by said slide will terminate their cutting movement and will be positioned in the same accurate relationshipto the work each time the feeding movement is terminated; As a result of this repeated accurate positioning of the tools relative to the work the machining of the work piece can be kept within extremely close tolerances and it will be unnecessary for the operator to manually move the slide against positive stops in order to complete the machining operation on the work piece. In other words, the slide can be repeatedly stopped in the same predetermined position to maintain the distance X indicated in Fig. 2 by the arrowed line to within a thousandth part of an inch, it being noted that said line represents the distance between the adjacent end surface of the slide and the end surface of th'e spindle.

In Figs. 2' to l1 inclusive positioning device of the invention disclosed therein and previously described in detail constitutes a device for automatically and positivelyv stopping and positioning the movement of the slide at the end of its forward or feeding movement only, while the stopping of the slide during its return movement is manually controlled by the operator, who also controls the direction of movement of the slide.

In Figs. 12 to 25 inclusive the connecting and positioning device of the invention sh'own therein is a device wherein the movement of the slide is automatically stopped and the slide positioned in both directions of its linear movement, while only the direction of movement of the slide is under the manual control of the operator.

There maybe instances where it is desirable not only to repeatedly stop and locate the slide in exactly the same predetermined position at the end of its movement in one direction, but also at the end of its movement in the opposite direction, and in such instances the connecting and positioning device would be advantageously employed. As illustrative of instances where this form of device could be advantageously used reference is made to the situation wherein the slide might have feeding movements in opposite directions, or might have only forward feeding movement but at the end of its return movement have additional func-v tions to perform.

Referring to Fig. l2, it will be seen that the shaft le is selectively operatively connected to the shafts 35 and i2 by identical mechanism as that used for the same purpose in the embodiment of the invention already described and, therefore, similar reference characters are employed to identify the identical parts or elements, except that the control lever for shifting the shiftable clutch element 45 will be identified by the numeral 8 l The shaft l5 in Fig. 12 extends into and is rotatably supported by a gear box 82 similar to the gear box 4I previously described, invthat it houses the connecting and shown in Figs. l2 to 25 inclusive the connecting and positioning device. The shaft 48' within the gear box 82 has fixed thereto a gear 83 which meshes with a gear 84, in this instance formed integral with a sleeve portion 85 and freely rotatable on a non-rotatable shaft 8B supported internally of the gear box 82 and parallel to the shaft |18.4 The gear 84 and sleeve portion 85 are held against endwise movement on the shaft 86 by a shoulder formed on said shaft and engaging one side of the gear 84 and by a gear later to be referred to freely rotatable on the shaft 86 and engaging the other side of the gear 84. The sleeve portion 85 is provided at its end with a radially extending boss 81 having a bore therein in which is slidably mounted a spring pressed driving plunger 88, similar to the driving plunger 53 previously described. Also freely rotatable on the shaft 86 is a gear 89 which has an elongated hub 98 extending axially of the shaft 88 and into the sleeve portion 85 of the gear 84. The gear 89 and hub 98 are axially shiftable on the shaft 88 and said gear 89 constantly meshes with an elongated gear 9| fixed to a shaft 92 which is rotatably supported in the gear box 82 and extends outwardly thereof toward the headstock and is provided with a screw threaded portion 93 that cooperates with the depending nut 94 carried by the slide 95 which slide is similar to the slide 32, shown in Figs. 1 and 2.

Theshaft 92 within the gear box 82 has fixed thereto a gear 96 which meshes with a gear 91 freely rotatably mounted on the shaft 88 intermediate one face of the gear 84 and the inner face of a bearing boss for said shaft 86. The gear 91 meshes with a gear 98 that is freely rotatable on the shaft 48 and is located within the gear box intermediate one face of the gear 83 and the bearing boss for said shaft 48. The gear 98 meshes with a gear 99 that is fixed to a screw threaded shaft |88 that is rotatably supported in suitable bearing bosses formed in the gear box 82 and extends, in this instance, parallel to the

shafts

48, 88 and 92. The gears 96, 91, 98 and 99 cause the screw shaft |88 to rotate in timed relation to the shaft 92 but at a different speed, in this instance.

An elongated block 19| is threadedly mounted on the screw threaded shaft |88 and is provided in its lower face with a longitudinal groove into which extends a xed pin |82, wherefore said block |81 is held against rotation or rocking movement but is free to move endwise on the screw threaded shaft |88 when the latter is rotated.

It will be seen that since the shaft |88 rotates in timed relation to the shaft 92 and screw 93 the block |81 will move linearly 0n the shaft |88 in timed relation to the linear movement of the slide 95 on the screw, but in this instance at a slower rate of movement. The block 18| is provided with a longitudinal T-slot |83 which carries a pair of cam lugs |84 and |85 that can be relatively adjusted in said slotand then clamped in adjusted position for a purpose later to be explained.

The hub 90 is provided with a track system, in this instance shown as including four circumferential grooves |86, |81, |88 and |89. The grooves |86, |81 are interconnected by a curved groove |18 which has a straight walled portion or section 11| midway between the grooves |85, |81 with said straight Walled section extending in a direction axially of the hub, or at right angles to the hubs rotation, see Fig. 22.

The annular groove |86 has a segment of variable depth with the high point of said segment at the juncture of the curved groove 1 18 with the groove |86, see Figs. 14 and 15. The groove |81 also has a segment of variable depth with the high point of said segment at the juncture o-f the curved groove 18 with the groove 181, see Figs. 14 and 17.

It will be noted that the curved groove H8 has two curved portions or sections on opposite sides of the straight walled section |11 but that such curved sections extend in opposite directions and therefore the high points of the grooves |86, |81 are oppositely disposed with respect to their relation with the curved groove |18, as clearly indicated in Figs. 15 and 17.

The annular grooves 188 and 189 are connected by a curved groove 112 having a straight walled portion or section H3 midway between the grooves |88, |89. The curved groove 112 is identical with the curved groove 118 but has its curved portions or sections oppositely disposed with respect to said groove |18. `Likewise the grooves |88, |89 each have a segment of variable depth with the high point thereof at the junction of the curved groove |12 with said annular grooves similar to the high points of the grooves |86, |81.

The form of the curved portions or sections of the grooves 118, |12 preferably Iwill follow a predetermined and desired curvature as will later be explained, and as previously stated with respect to the curvature of the curved groove Ell of the earlier described embodiment of the invention.

The gear box 82 is provided with an internal bracket having a-pair of parallel bores in which are slidably mounted identical two-part plungers identified in their entireties at |14, |15. These two-part plungers are each similar to the twopart plungers 68, 81 of the previously described form and each comprises inner and outer plunger parts operatively interconnected and held in extended relationship with respect to each other by a coil spring. The outer parts of the twopart plungers 1 14, 5 are provided at their outer ends with forks which are embraced by the forked outer ends of the opposite arms of a lever |16 which is rockably supported by the internal bracket that carries the two-part plungers. The lever 118 intermediate its ends and on its inner edge is provided with a V-notch with which a spring point 111 cooperates to hold the lever in its inactive positiony as indicated in Fig. 13. The lever |18 is also provided intermediate its ends and on its outer edge ywith a laterally extending arm |18 which has its outer end of spherical formation. The arm 118 extends between the adjustable cam lugs |88, 185 of the block |81 and said cam lugs will abut one side or the other of said arm as said block moves linearly in opposite directions to rock the lever IIB in one direction or the other to move either the two-part plunger |14 inwardly and the twopart plunger |15 outwardly or vice versa as will later be further explained,

When the lever |18 is in its inactive position 13 as shown. in Fig. 13, the two-part plungers H4 and..` I i5 will have their inner ends extending slightly into the grooves m5, im ofthe hub' 9B and said two-part plungers at such` time prevent any axial shifting movement of the hub but permit the free rotation thereof.

1t will further be noted that the driving plunger 88, depending upon the axial poistion ofthe hub Si?. extends at all times either into the annular grooves` it', 25S or into the curved groove H2 of the hub, said driving plunger 88 being shown in Fig. 13 as extending into the straight walled section l i3 of the curved groove H2.

In order to clearly explain the purpo-se of the construction shown in Figs. 12 to 25 inclusive and herein described the manner in which said construction functions will now be explained. Assuming that the operator has disengaged the shiftab-le clutch element 56 from theA clutch element 3S to stop the' movement of the slide before it has completed its forward feeding movement and while it was in feed as indicated in Fig. 12, it will b-e seen that at this time the two-part plungers i ill, i' i 5 extend slightly into the annular grooves iiiii, itil to prevent axial shifting of the hub while the driving plunger 88 is in the straight walled section H3 of the curved groove H2 of the huh iid as indicated in Fig. 13. At this time the arm H8 of the lever ile is situated intermediate the cam lugs iM, m5 of the block mi and which lugs have been positioned in accordance with the desired extent of travel of the slide S5 in opposite directions. At this time also the lever i 16 is in its inactive position and is held in such position by the spring point H1. When the operator wishes to continue the forward feeding movement of the slide 95 and the parts being in the relationship shown in Fig. 12 he moves the control lever Si to engage the shiftable clutch element 45 with the clutch element 39', whereupon the shaft la again rotates in timed relation to the rotation of the work spindle with a resultant rotation of the huh 99 and Shaft 92 and screw 93 due to the driving action of the plunger 88 in the straight walled section H3 of the curved groove H2 and .the fact that said hub portion is held against axial movement by the two-part plungers lill and H5.

It will be noted by referencev to Fig. 22 that the i plunger 88 drives in the direction of the arrow 88a and that the hub revolves in the direction of the arrow Sila. The slide 95 is now moving forward in feed and the screw threaded shaft I0!) is rotating .in timed relation to the shaft 92 and the block lili is moving line-arly toward the left, as viewed in Fig. 12, in timed relation to the movement of the slide. As the slide 95 approaches the point at which its feeding movement is to be terminated the block lill has moved sufficiently far so that the cam lug 105 has started to contact the arm H3 of the lever H5.' The continued movement of the slide 95 and `the block lo! causes the cam lugV HB5 to rock the lever IIB from the position shown in Figs. l2 and 13 to the position shown in Fig. 18, with la resultant .radial inward movement of the two-part plunger lili into the groove lee and a withdrawal of the two-part plunger H5 from the groove l01.

The slight rotary movement of the hub Si! after the plunger H4 has moved into the groove |05 causes the plunger Htl to relatively travel out of the annular groove Iil and into the curved groove i 1S as indicated by dash lines in Fig. 24l until said plunger has reached the straight walled section direction with a gradual acceleration and this .f

- 114 Ilfl ofthe curved groove at which time the rotation ofthe hub 9i) is positively stopped.

It will be understood that the extent of the continued rotation of the hub 9D after theplunger IM has been moved inwardly depends upon the position in which the plunger moves radially inwardly of the groove |05 with respect tothe curved groove Iii). It will be understood that should the plunger H4 move into the segment of the groove i U6 of variable depth, the plunger will simply he momentarily depressed against its coil spring until it is in the part of the groove which is of maximum and constant depth.

It will also be understood that as the plunger lid* moves in'to the curved groove H0, as indicated by dash lines in Fig. 24, the hub Q will be shifted axially toward the left, it being recalled that the plunger H5 has been moved entirely clear' of the hub 90. This axial shifting of thehub 9!) toward the left causes the driving plunger 83: to move out of the straight walled segment M3' of the curved groove |52 and through the latter as indicated by dash lines in Fig. 24 and into the annular groove m9, said driving plunger 33T reaching the annular groove simultaneously compress the plunger against its spring upon each revolution of the sleeve portion 85.

It will be understood that the arrangement of the plunger Hd in the straight walled section Iii of the curved groove H0 instantly and positively stops the rotation of the hub 9i), screw 93 and the feeding movement of the slide which is connected to the hub by an uninterrupted drive train. The stopping of the rotation of the hub 9@ also results in stopping the linear left hand movement of the block lil! which likewise is connecteolv to the hub through an uninterrupted drive train.

When the operator wishes to initiate the rearward movement of the slide S5 he shifts the control lever to disengage the clutch element 46 from the clutch member 39 and engage said element with the clutch member 45, whereupon the shaft d will rotate in the opposite direction and at a more rapid rate. This reverse rotation of the shaft iii causes the sleeve 85 and the driving plungerv B8 to rotate in the opposite direction from that indicated in Figs. 22 and 2li, with the result that the plunger 83 moves out of the annular groove 599 andinto the curved groove H2 until it reaches the straight walled section l I3 of the latter groove, as indicated in Fig. 22. This movement of the' driving plunger 83 in the curved groove H2 and into the straight walled section H3 eiects an axial shifting movement of the hubl toward the right with a resultant relative movement of the two-part plunger l i4 out of the straight walled section. ill of the curved groove lill and through the latter groove and into the annular groove HB5. The instant that the driving plunger d8 engages in the curved groove H2 and the two-part plunger l la rides out of the straight walled portion HI the driving plunger S8 positively drives or rotates the hub Si) in the reverse reverse rotation of the hub results in a reverse rotation of the shaft 92, screw 93 and the screw threaded shaft |90, with the result that the slide 95 moves linearly rearwardly while the block |0| moves linearly toward the right. The movement of the block lili results in the cam lug |05 moving out of engagement with the arm H8 of the lever H6 which allows the spring point to act and restore the lever H6 to its inactive position as shown in Fig. 13, with the result that the twopart plunger I I4 is moved radially outwardly and the two-part plunger H5 radially inwardly until both plungers are in the position shown in Fig. 13 wherein they act to hold the hub 95 against axial shifting movement but allow it to rotate freely.

It will be understood that when the two-part plunger H4 is moving radially outwardly from the position shown in Fig. 18 to the po-sition shown in Fig. 13 the cam lug |95 controls the rate of such movement until the lever IIE has fully reached its inactive position and should the plunger H4 during this controlled movement contact the high portion of the groove |96 said plunger will be momentarily compressediagainst its spring. The slide 95 continues its rearward movement while the block IGI continues its linear movement toward the right until the cam lug |95 contacts the arm H8 of the lever H6.

When the slide 95 is near its predetermined limit of rearward movement the cam lug |04 has been brought by the movement of the block I| into contact with the arm H8 of the lever H8. The continued rearward movement of the slide and the right hand movement of the block IGI results in said lever H6 being rocked from its inactive position shown in Fig. 13 into the position shown in Fig. 20. The rocking of the lever H to the active position of Fig. 2O withdraws the two-part plunger H4 completely from the groove |95 and moves the two-part plunger H5 radially inwardly of the groove I 6T, whereupon said two-part plunger H5 and the hub 99 are relatively displaced to cause the plunger H5 to ride out of the groove |91 and into the curved groove H6 until it is in the straight walled section III of the latter groove, this relative movement of the plunger being shown in Fig. 25 by dash lines.

The relative movement of the plunger I I5 just referred to brings about the displacement of the hub in a right hand axial direction, with the result that the driving plunger 88 moves relatively to the curved groove H2 from the straight walled section H3 thereof and into the annular groove |08, such movement being indicated by dash lines in Fig. 25 and occurring simultaneously with the relative movement of the two-part plunger H5 into the straight Walled section IH of the curved groove HB, wherefore the instant that the two-part plunger H5 is in the straight walled section HI said plunger functions to stop the reverse rotation of the hub 90 (indicated in Fig. 23 by arrow 90b) While the driving plunger 88 travels idly around in the groove |98 in the direction indicated by arrow 88h in Fig. 25, it being understood that the driving plunger 88 is compressed momentarily against its spring each time said plunger travels over the high part of the groove 98.

The stoppage of the reverse rotation of the hub 99 immediately acts through the uninterrupted drive trains to the screw S3 and slide 95 and to the block 19| to stop and position the same in their predetermined rearward locations. The

operator Vmay allow the shaft 49 and the sleeve 95 to continue rotating idly in the reverse direction, but most probably he will shift the control lever 8| to disengage the movable clutch element l5 from the clutch member 45 and thus terminate the rotation of the shaft 59 and sleeve 85. He then can remove the finished work piece and insert a new work piece, after which he will shift the control lever to engage the clutch element 45 with the clutch member 39 and start the rotation of the shaft 49 and sleeve 85 in the forward or feeding direction.

As soon as the sleeve 85 starts to rotate in the forward direction as indicated by the arrow 88a in Fig. 22 the driving plunger enters the curved groove H2 and travels relatively therein until it is in the straight walled section I I 3 of the groove as indicated by dash lines in Fig. 25. The relative movement of the driving plunger 88 into the curved groove I l2 eifects a left hand axial shifting of the hub 99, with the result that the twopart plunger H5 moves relatively in the curved groove HG from the straight walled section Il I of the latter groove and into the annular groove il?? as indicated by dash lines in Fig. 25 and which movement of the two-part plunger H5 is simultaneous with the movement of the driving plunger 88. In other words, the instant that the driving plunger 85 rides into the curved groove H2 and the two-part plunger H5 rides out of the section Hl the hub 99 is free to rotate and the plunger 88 will so rotate the hub in the forward direction with a gradually accelerated movement. The rotation of the hub 9B in the forward direction immediately starts the feeding movement of the slide and the linear movement of the block I9| toward the left. As the block I9! moves toward the left the cam lug |04 moving therewith allows the lever H6 to be rocked by the spring point l Ill from the position shown in Fig. 2O 'to its inactive position as shown in Fig. 13 and at this latter time the two-part plungers lill and H5 extend slightly into the grooves |55, I'i and hold the hub 99 against axial shifting and the condition indicated in Fig. 22 is now current.

It will be understood that during the movement of the lever H6 from the position of Fig. 20 to its inactive position as shown in Fig. 13 the twopart plunger H5 will be compressed each time it strikes the high point of the groove |01 until the lever I6 has reached its inactive position and such compression `of the two-part lever H5 will assist the spring point in restoring the lever to its inactive position. The slide 95 is again in feeding movement and the block IUI is moving linearly toward the left in timed relation to the feeding movement of the slide and the cycle of operation previously described will be repeated and the slide stopped and positioned accurately and repeatedly at the end of each of its forward movements and at the end of each of its rearward movements.

Although the slide 95 has been shown as not provided with an indexible turret for the sake of simplicity, it will be understood that the invention is readily adaptable for use in a machine tool employing an indexible turret on the side. In such case the indexing mechanism which is well known could be operatively connected to the block IBI to index the latter in a well known manner and such block would then be provided with a plurality of faces for sets of cam lugs |04, |95 and corresponding in number to the faces of the indexible turrent.

1:7 It will be understood that although the invention has been shownV as used in. connection with the mainslide of a machine toolr it couldybe em.-

ployed with equal facility in connection withother slides of a machine tool and including; the cross,

slide carriage and cross slide and can also be employed in any other mechanism` where such. af,

clutching device is desirable.

It will be understood that the forward rotation of the shaft 40 need notbe. entirelyintimed relaf tion to the rotation of. the work spindle, sincesaid shaft can be rotatedv in the forward direc.-v tion at a faster rate as is Wellknown in theart.. in order to impart a. fast. forward movement to...

the slide and then a feeding movementxand in such an arrangement the connecting. and posi,-

toning device of the4 invention would; functiony in the identical manner.

The grooves in the. hubs, Bland 9.0` Whichconnectl the annular grooves insaid hubs havebeen illustrated as curved. grooves with intermediate straight walled sections extending. axiallyfof theV hubs. It should be understood thatA said connecting grooves: might have various forms of cur'- vature or. even might be straight angularly disposed'V forms of. camming grooves interconnectingv thevannular. grooves. However, in orderto avoida. hammer blow effect inthe starting4 and stop-- ping ofthe. parts and'to provideadesirable and smooth acceleration and deceleration of the parts' it is preferable and important to employ curved connecting grooves.V Tests have indicated a particular form of curvaturewhich may be followed-A in*A forming .the curved portions of the grooves of, the track'. system and which curvature is such-l thatl the. Imovements of the driving plungerand the, holding plunger therein will result in a gradual and smoothA acceleration or deceleration in the speed of rotation of the hub and will avoid The particular form of' hammer blow effects. curve just referred to is derived. from a formula analogous to the law of-fallingbodies, since'the` degree of curvature of progressive portionsy of the curve decreases from-the point of origin of*l ofincreasesfrom the straight walled section in,

proportionv to the square of the relative axial distance which they travel.

Fig. 26 illustrates the development ofthe preferred curve employed n forming the curved: portions of the grooves constituting the track' system in the peripheries ofthe hubs and in which.,

curved portions'- the driving and' holding plungers relatively travel. The point of' origin ofthe. curve of the curvedV portions is indicated" at O and" that portion of the curve derivedl from the :fornlula extends to the point M, while the portion` MN of the curve is formed on a radius. The equation employedin plotting the curve OM is as follows. X.2=2PY Where theA quantity 2P is determined by thedesired ratev of hub acceleration or deceleration. ln this instant case the quantity 2P is taken as .64 for one inch axial' shiftingv of the hub. This form-ulaY enables eachpoint= of'- theL curve to be determined and plotted by assigning the actual values to the coordinates, for example tol determine point K of the curve and either the distance X or Y as indicated in Fig. 26 being known, its actual value is substituted in the formula to` determine the actual distance of the other. In laying out the curve OM a sufcient eration whichcan be imparted to the hub by they driving plungen. Fig. 26 illustrates by dash and dotl lines. such movement of the holding

plunger

6,6. It will be understood that when the holding plunger 66 is moving from the straight Walled sectionof'the track` system through the curved portion' thereof. to the annulargroove the driving plunger isr moving from an annular groove through a curved portion and toward the straight Walledsection and that such movement of the driving. plunger inits respective curved portion of` the groove. is governed byy the movement of they holding` plunger inits 4respective curved portion of the groove. Therefore since the movemeritl of the holding; plunger is a controlling f actor` and inu order to facilitate the description of thecurvev the action of the holding plunger 66 in` thecurved groove will be described. When.

the holding,v plunger 66 is retaining the hub stationaryv the center of said plunger is approximately at pointv H and when said plunger has movedgits center, to the point of origin Ol ofthe curve due to theaxial shifting of the hub by the driving plunger said holding plunger is still in thev straight Walled. section G5 of the groove. 64. Asthe center'of the plunger 65 moves from point Q to p oint Kl it has traveled the distance of vertical increment I, as indicated in Fig. 26, and whichrdistance represents the axial displacement of the hub and said plunger, has also traveled.

theV slight distance of horizontal increment l and which distance represents the permitted relative rotation of the hub under the action of the driving plunger Whichis moving relatively in its respective curved portion of, the4 groove as will be understood. The movement of the center of the holding plunger 66 from point Kl to point K2 takes. place during the axial displacement of the hub'A by the driving plunger for. the equal vertical increment 2 and such movement of the holding plunger permits a relative rotative movement of the' hub under the action. ofi the driving plunger as indicated by the larger horizontal increment 2. In the same way when the center of the holding plunger 66 moves from point K2 to point K3 as the hub'is. axially displaced a third equal verticalv increment by the driving plunger, the permitted relative rotation ofthe hub under the action of the; drivingv plunger is equal to horizontalr increment 3` which. is substantially greater than horizontal increments I and 2. As the center of the holding plunger moves relatively along the curve. from point K3 toward point M as thehub is axially displaced in equallyv vertical increments forV each successive relative movement of'- the holding plunger, as clearly shown in Fig. 26,

the allowedrelativerotation of the hub under the actionA of the driving plunger progressively increases for each suchincrement until the center of the holding plunger has reached point M of the curve. When` the center of the holding When rotation of the sleeve 50 is reversed theholding plunger 65 moves out of the straight Y walled section 65 and into the curved portion 64 of the groove due to the driving plunger 53 simultaneously moving out of the annular groove E3 and'into the curved portion and exerting both driving and axially shifting effects upon the hub with the holding plunger controlling this driving effectand permitting the acceleration of the hub fromlzero to its maximum driving speed in the reverse direction as explained above. It will also beunderstood that conversely when the driving plunger 53 moves out of the straight walled section 65 and into the curved portion of the groove under the action of the holding plunger moving into the curved portion of the groove toward the straight walled section thereof, the rotation of the hub underthe action of the driving plunger is controlled by the holding plunger and gradually decelerated from maximum speed to zero. Consequently the smooth acceleration and deceleration incident to starting and stopping the rotation of the hub eliminates hammer blow effects between the driving and holding plungers and the hub, since said plungers enter Vthe straight Walled section of the groove when the hub has reached full driving speed or has had its rotation substantially diminished.

Referring again to Fig. 26, it will be seen that the curve developed from the formula terminates at point M and from said point onward to point N the curvature is formed by a pure radius and merges into .the annular grooves of the hub and provides for a smooth action when the plungers enter orleave the curved groove. v

It will be understood that although theV description relating to Fig. 26has referred specifically to the curved groove 64 this was merely by way of example and that the same curvature is utilized' forall of the curvedgrooves illustrated and described herein with respect-to all of the embodiments of theinvention.

Fig. 27 shows a different form of track system than those shown in the previous views. In this latter form the annular grooves are not-interconnected by curved groove portions or sectionsv withthe latter joined by straight Walled portions or sections. Referring to Fig.' 27 it will be noted that the hub shown therein has annular grooves I I9 and I 20 from Ywhich extend, respectively, curved groove portions |2| and |22. The portion |2| has at itsv end a straight Walled section |23 1 while the portion |22 similarly has a straight walled section |24. The sections |23 and |24 would constitute driving and stopping sections if this form of track system were substituted for that shown` in Figs. 1 to 11v inclusive and would constitute separate stopping sections if used in place ofthe grooves |06, |01, III) and ||1| of the form shown vin Figs. l2 to 25 inclusive.

Although several embodiments of the invention have been illustrated and described hereinit will be understood that the invention is susceptible of such modications andadaptations ascome within the scope of the appended claims. Y Y n Having thus described our'invention, we claim:l

20T 1, A device ofthe character described comprising` a `driving member, a movable member, and means selectively functioning to operatively connect the members and to positively stop said movable memberin a predetermined position after a selected predetermined movement thereofy and including a track system on one of said members and having endless portionsand interconnecting portions therebetween., a driving element carried by the otherzof said members, and a stopping element mountedindependently of said members, both of said elements cooperating with said track systemA the said driving element continuously engaged with said track system. l 4

. 2.,'.A device ofthe character described comprising a; driving member, a movable member, and

means selectively functioning to l operatively con-y nect the members and to positively stop said movable member in a predeterminedposition after a selected predetermined movement thereof and including a tracksystem on'- one of said members and having endless portions and interconnecting portions therebetween withthe latter portions including camming sections and a straight section,

a driving element carried by theother ofsaid members, and a stopping element mountedindependently of Said4 members, both of said elements cooperatingwith said track system the said drivingelement continuously engaged with said track System,

3, device ofthe character described compris ing a driving Vmembena member shiftableV relativel to saidrdriving member and also movable therewith, andvmeans selectively functioning tov operatively connect the members for movementy thereof vv'i'tlsaid driving member or to stopxsaid,

secondnamecl member, said driving ,element beilacolrltinuously in engagement withsaidtrack "el,` A lev'icefof vthe character described comprising adriving member, Ya, Asecond member shiftable relative` tothe driving member and also movable therewitnfand means selectively functioning to operatively connect the members for movement together 'an'd'to'positively stop said second member'in a'predetermined positionand including a track system on one `of'said members and having endless' portions and Vintereonnecting portions therebetween -with the latter portions including camm'ing"sectionsV andastraight section, a drivingelementcarried by the other of said membersl andl'z, .stopping element mounted independently of' said menbers, both oflsaid elements, cooperatingjwith said*l track systemdto shift the second memberrelativemto the driving member and into a stopping position ora driving positionwherein eachjelement may perform, respectivelyjtsstopping or; ldriving rfllnlilfl,l said .driving element be.

inggcontinuollsly in engagement with said track system..r; Y m .u .l

A; Cllioelof the characterdescribed comprisr,

inga driving member, amovablemember, and;

21 means selectively functioning to operatively connect the members and topositively stop said movable member in a predetermined position and including a system of endless grooves formed in one of said members, a driving element carried by the other of said members, and a stopping element mounted independently of said members, both of said elements cooperating with said system of endless grooves with said driving element oontinuously engaged in said grooves.

6. A device of the character described comprising a driving member, a movable member, and means selectively functioning to operatively connect the members and to positively stop said movable member in a predetermined position, and including a track system on one of said members and provided with a driving portion and with a stopping portion, a driving element carried by the other of said members and continuously cooperating with said track system and with the driving portion thereof, and a pair` of elements mounted independently of said members and cooperating with said track system and alternately with said stopping portion thereof depending upon the direction of movement of the movable member.

7. A device oi' the character described comprising a driving member, a movable member, and means selectively functioning to operatively connect the members and to positively stop said movable member in a predetermined position and including a system of endless grooves formed in one of said members and provided with a driving and stopping portion, a driving element carried by the other of said members and continuously extending into and cooperating with said grooves and said portion thereof and another element mounted independently of said members and continuously extending into and cooperating with said grooves and With said portion thereof.

8. A device of the character described comprising aV driving member, a movable member, and means selectively functioning to operatively connect the members and to positively stop said movable member in a predetermined position and including a system of endless grooves formed in one of said members and having a driving portion and a stopping portion, a driving element carried by the other of said members and continuously cooperating with said grooves and with the driving portion thereof, and a stopping element mounted independently of said members and cooperating with said grooves and with the stopping portion thereof.

9. A device of the character described comprising a driving member, a movable member, and means selectively functioning to operatively connect the members and to positively stop said movable member in a predetermined position and including a system of endless grooves formed in one of said members and having a driving portion and a stopping portion, a driving element carried by theother of said members and continuously cooperating with said grooves vand with the driving portion thereof, and a pair of stop elements mounted independently of said members and cooperating with said grooves and alternately with the stopping portion thereof depending upon the direction of movement of said movable member.

10. A device of the character described oomprising a reversible driving member, a movable member, and means selectively functioning to operatively connect the Vmembers and to posi-V tively stop said movable member in a Apredetermovement thereof in one direction and including a driving element carried by one of said members, a stopping element mounted independently4 of saidmembers, and a track system on the other of said members and cooperating with both said driving and stopping elements, said driving element automatically cooperating with said track system when said driving member is reversed to render inactive said stopping element and to operatively interconnect said members to move the .movable member in the reverse direction.

11. A deviceof the character described comprising a driving member,- a movable member, and means selectively functioning to operatively connect the members and to positively stop said movable member in a predetermined position and including a driving element carried by one of said members, a stopping element mounted independently of said members, and a track system on the other of said members with which said elements cooperate with said driving element continuously engaging said track system, said track system comprising annular portions and interconnecting portions therebetween with the latter portions including curved sections and a straight section. Y

12. In a device of the character described comprising a driving member, a movable member, and means selectively functioning to operatively connect the members and to positively stop said movable member in a predetermined position and including a track system ony one of said members and having a pair of annular portions and an interconnecting portion therebetweenl capable of shifting movement relative to the driving member and also driven movement therewith, and means selectively functioning to operatively connect the members and to positively stop said second member in a predetermined position after a predetermined driven movement;

thereof and including a track system on one of said members and having a pair of annular portions and an interconnecting portion therebetween with the latter portion including curved sections joined by a straight driving and stopping section, a driving element carried by the other of said members, and a stopping velement mounted independently of said members, each of said elements cooperating with saidtrack system, with the driving element cooperating with one of the curved sections to shift the movable member and relatively displace the stopping element with respect to the driving and stopping section while the stopping element cooperates with the other curved section to shift said movable member and relatively displace the drivingV element with respect to said driving and stopping section. Y

14. In a device of the character described com- Vprising a driving member, a second memberv capable,Y of.; shifting. v.movement relativeto. the.

driving.:.member. and. also of driven..movement.

therewitl1`,fand means selectively functioning'to.;

operatively'connect the members andtov positively stopsaid. movable member inla predetermined. position after a predetermined.drivenzmovement;

thereofzandincludingy a tracky system. on one` of saidv members comprising twofpairsrof; annularY portions with .the annularportionsV of each.. pair interconnectedA by a connecting portion, .each connecting portion including .curved sectionsv joined. by a .straight section.. a .driving element carried. by the .other of: said! members andcooperating with .one pair of. annular portionsof said. track system and withv .the curvedi sections" oftheY interconnecting portion thereof to;V shift said movable member and withthetstraight. section'` to drivev said movable member', and aA pair of stoppingelements mounted independently.

of saidmembers and .cooperatingiwith theother pair of. annular portions of said .track system" and. valternately with the curvedsections .ofI the'connecting. portions itherebetweenjto shift said mov'- able` member and. with lthe straight .section to..

stop the movement of saidimovable member;

415. .In combination,.a slide, means. iformoving.

said slide in opposite directions andi'forpositively stoppingr themovement thereof lin predetermined positions'. and including a single ldriving member, a. movable member; an uninterrupted operative connectionbetween said movable member and saidsslide, and meansfor operativelyconnecting.;

said members and for positively stopping. the

movable; member andslide in a predetermined. position. and including aA trackr system on one. ofy saidmembers; a driving .element on the `other vofsaid-mernbers and cooperating. with saidtrack system to'operatively interconnectthe members,

and. a pair of. stopping elements mounted inde-1 pendently ofsaid members andalternatelycooperatingwith said track system/ to stop :the movement of. the movable member and the slide in Opposite directions,Y and control means moving`A in .timed relation: to said slide .and operatively associated .with said stoppingA elements. for Yalter-A nately rendering one or the other ,active de.. pending upon the direction of movement-of the2 slide.. 16.` A device of the character described comprising adriving member, a second member capablo of .shifting .movement relative tothe "drivingrnember` and;` also capable of driven movement therewith, and .means selectivelygiunct'ioning4 to operatively connect the.members..and.1 to

positively stopsaid second member in a vpredetermined.; position after a predetermined given.

movement thereof. and includingxa track systeml on one of said membersand having a pair of .ane` nular portions each of which connects with a.. curved section; and a straight section, a driving..

element carried by the Aother of said members and.

cooperating. with oneof said; annular portionsof z said .tracksystem toprevent shifting movement of ksaid'second. member and. with'fone. of .said c urved sectionsV toy causeshifting' movement .ofA

said ,memberand with said. straight section; to

drive *sa-id., member, and'A a stopping.. element.

mounted independently of said members. and cooperatingv with the otherannular portion ofY said. track systemY to prevent shifting movement... ofi said-second member and-with; the othercurved; section-:thereof to" cause shifting. movement of. said second member and with the other straight.:

section, .t stop.l the.. driven .movement of. .the second memben. 1 f

. .24Sv 17.. Ay device of the character described com. prising. a-clriving member; a second member capable; of. shifting movement :relative to the vdriving member and also'drivenmovement therewith,

andVv meansselectively functioning to operatively connect the membersiand to positively stop said'. second member in a. predetermined position after.Y` a predetermined .driven lmovementA thereof and-f. including. a` track system on one ofv said members..V and having annular portions, straight driving.

and stopping...sections,. and curved. portions.. connectingsaid .straight sections and saidV annularA portions, a driving'element'carried by the other. of said membersnand cooperating'with ce'rtainiof tions `of saidy track systemv following a predetermined curvature'` such thatA the cooperation be-A' tween --saidportions and the driving: and stopping elementseffects al smooth and gradualaccelera'- tion anddeceleration of the-second member in commencing the movement of said member andiin stopping'themovement thereof'.

-l8; A`v device Aof the character described com-fprising a dri-ving member, a movable member, and means selectively functioning to operatively connect the members and to positively stop said movable member in a predetermined position after a selected predetermined movement there' of and includingV atrack system on one Aof said members and having endless portions communi-'l eating with camming portions and driving andstopping sections, a driving element carried'by thesot-her of said members and continuously co`` operating with said track system and a stopping element mounted'independently of said members and also cooperatingwith said track-system; 'said cam-ming portions; having a predetermined contour suchthat;V the movement of ther movableV memberis gradually and smoothly accelerated Aor decelerated'upon the initiation of its movementW byr'the'ldriving element orv upon the-initiation-of* the stopping eiect vthereon bythe stopping 'element.V f

19. Ae device `of the character described com` prising'- a Vdriving member, a movable member,- and `meansy selectively functioning to VoperativelyY connectv theA members and to positively stop said movable member inY a predetermined position after a selectedpredetermined movementthereof :and including Ya track system on one'ofvsaid members-andhaving endless portions-and curvedVV portions and drivingand stopping sections,` ar driving element carried by theother ofsaidmem# bers, andf aA stopping element mounted-independi ently'of 'said members, botnof said elements Acooperating vvith saidv tra-ck system; the'curvaturev of said curved portions' followinga-formula based ongthe-law'of falling-"bodies, namely `X2=2PYl Where-the `quantity 2E is determined-by theirate" of acceleration vor'deceleration' desired for the' movable-finember While'X andzY represent'the values ofthe Ycoordinates for locating; the points along gthe desired curve.

20. A device ofn Athe character-y describedY comprisinga fixed shaft, a drivingmember freelyjro;

tatableonsaid shaft, a movableV member freely rotatable and-endwise movable on'said shaft, and-l meansselectively functioning to operativelyjcone" nect-.theQmembers and-to positively stop 'rotation-4 of.:.said: movable "mem-ber -in a" predetermined `pof and including a, driving element, a stopping element and a track system cooperating with both of said driving and stopping elements.

21. A device of the character described comprising a fixed shaft, a driving member freely rotatable on said shaft, a movable member ireel rotatable and endwise shiftable on said shaft,

and means selectively functioning to operatively connect the members and to positively stop rotation of said movable member in a predetermined position after a selective predetermined movement thereof and including a track system on one of said members and having endless portions and interconnecting portions therebetween, a driving element carried b-y the other of said members, and a stopping element mounted independently of said members, both of said elements cooperating with said track system.

22. In combination a rotatable shaft, an elongated gear fixed thereto, a fixed shaft, 9, driving member freely rotatable on said fixed shaft, a

movable member freely rotatable and endwise sniftable on said fixed shaft, gear means opera- 26 tively connected with said movable member and intermeshing with said elongated gear, and means selectively functioning members and to positively stop rotation of said movable member in a predetermined position after a selective predetermined movement thereof and including a track system on one of said members and having endless portions and interconnecting portions therebetween, a driving element carried by the other of said members, and a stopping element mounted independently of said members, both of said elements cooperating with said track system.

MYRON S. CURTIS. HARRY SCHOEPE.

Date Dec. 6, 1932 Number