US2669345A - Out-of-stock responsive mechanism - Google Patents

Description

Feb. 16, 1954 R w, BROWN 2,669,345

OUT-OF-STOCK RESPONSIVE MECHANISM Filed Sept. 10, 1949 4 Sheets-Sheet l Feb. 16, 1954 R, R N 2,669,345

OUT-OF-STOCK RESPONSIVE MECHANISM 122x22??? W2 ldfzawfa Patented Feb. 16, 1954 2,669,345 OUT-OF-STOCK RESPONSIVE MEfiHANISM Roger W. Brown, Windsor, Vt., assignor to Cone Automatic Machine Company Inc., Windsor, Vt., a corporation of Vermont Application September 10, 1949, Serial No. 115,069

2 Claims.

In connection with lathes and screw machines which operate upon lengths of stock fed through one or more rotary work spindles, it is desirable for the operator to know when the stock is exhausted in order idle operation of the machine.

An object of the present invention, therefore, is to provide simple and effective means for indicating out-of-stock condition to the operator, and, if desired, for stopping the machine automatically or performing any other desirable function on the occurrence of such a condition.

A further object of the invention is to associate such an indicator, together with such automatic controls as may be desired, with a stock feeding mechanism, the absence of the stock from such mechanism at any time resulting in the operation of the indicator and parts controlled thereby.

A further object is to provide means for imparting a slight forward and backward motion of a portion of the stock feed mechanism effective when the normal resistance to such motion produced by the presence of stock fails, as it would fail should no stock be present, to give notice and effect such automatic controls as are desired.

A further object of the invention is to provide indication of an out-of-stock condition whether or not the pusher has appreciable return stroke friction.

Further objects and advantages will appear from a description of an embodiment of the invention shown in the accompanying drawings in which:

Figures 1 and 2 are end and fragmentary front elevations of a multiple spindle lathe embodying the invention.

Figure 3 is a detail sectional View to a larger scale on line 3-3 of Figure 1.

Figure 4 is a fragmentary View partly in front elevation and partly broken away and in section and to a larger scale than Figure 2, showing certain portions of the mechanism, the stock feed being in retracted position.

Figure 5 is a fragmentary view similar to a portion of Figure 4, but with the parts in different positions as when the stock is in the spindle and has been fed forwardly.

Figure 6 is a sectional detail of the forward end of the spindle, a piece of stock having been gripped and fed.

Figure 7 is a view similar to a portion of Figure 4, but showing the mechanism in condition of out-of-stock just before this is effective on the responsive mechanism.

Figure 8 is a View similar to a ure 7 and showing the parts in condition.

Figure 9 is a fragmentary vertical sectional view showing the stock gripper actuating mechanism.

Figure 10 is a detail sectional view on line iB--iii.of Figure 9.

Figure 11 is a detail sectional view to an en-- larged scale on line |lll of Figure 9.

Referring first to Figures 1 and 2, there is illustrated a portion of a multiple spindle lathe or screw machine having an indexing spindle carrier i mounted for indexing motion about its axis 2 to present successively a plurality of hollow rotary work spindles 3 in the various tooling positions. The indexing is produced by a Geneva motion comprising the rotating Geneva arm 3 having a cam roller 5 which cooperates with Geneva slots 6 in a suitable portion of the spindle carrier I. This Geneva arm is rotated by means driven in time with a cam shaft '5 positioned above and substantially parallel to the axis of the spindle carrier. This cam shaft 1' carries suitable cams for controlling the various portions of the cycle of operation of the machine as is well understood in the art. Each of the work spindles is hollow, as shown best in Figure 8, and carries at its forward end a work-gripping collet II] which may be moved portion of Figout-of-stock axially and which is provided with jaws having tapered outer faces H which cooperate with a mating tapered inner face [2 of the spindle, so that the work piece 15 may be gripped while machining operations are being performed on an extended portion thereof, or released for feeding of the stock through the spindle. Mechanism for opening and closing the collet It] in proper time is old and well known and may be as shown in the Cone Patent No. 2,142,557 granted January 3, 1939. This mechanism is shown more particularly in Figures 9 to 11, inclusive. The work gripping collet or clamp H is carried at the forward end of a sleeve Hill axially slidable within the spindle 3 and rotatable with this spindle. The sleeve Hit! has a collar IOI secured to its outer or rear end, the forward end of the collar carrying a support I02 having slots for the pivotal reception of fingers I03. These fingers are each provided with a lug l 04 which bears against the end of an outer axially fixed sleeve I 05 forming a portion of the spindle and on which is axially movable a wedge collar I06. This collar its has a tapered end I01 against which the ends of the fingers I03 engage. When the wedge collar 108 is moved toward the left as viewed in Figure 4, the fingers I03 are wedged outwardly and the collar Nil and the support I02 are forced toward the left, retracting the collet l and clamping the work piece therein. Motion of the wedge collar 51%. to :the right will then allow the collet is to move in the same" direction and release the work piece. This motion of the collar W5 is produced in cam drum Hi8 (Figures 9 and 10) carried by the cam shaft '1, the cam ll5*-acting one 185 carried by a slide connected to a second slide I ll carried by a sup-- porting bar H2. Slide engageable in a peripheral groove H4 in the collar angular position about the axis of the shaft 2 to have -the stock =fedtherein. l

The feeding is produced by a pusher :1 6: of :any suitable ty-pe-.which is .reciprooated. j The forwardmotion of the pusher ordinarily; occurs while the collet I0 is released, thus feeding. the stock through the stock clamp up against a stock. stop (not shown) and the pusher .is. retracted normally while the clamp is closed so that the stock pusher rides backwardlyrover the stock without moving it.

The stock-pusher- 16 extends outwardly beyond the end of thee-spindle where it is provided with a head 253' shown best in Figures 3 and 4. o This. head maybe engaged-inxa peripheral groove 2L of a spool-shaped member 22F 1Otatab1y' mounted on a bushing-.23 carriedby a pin shaft 24 which extends through a yoke 25.3. Itis secured in: this yoke by a transverse spin 26'; .passed through a slot therethrough oppositelto thehead end 21. of the pinxshaft." Theiyoker'. tisf1xed between a pair of lugs 28 :anddevona block; 30zwhich: is secured to the outer endlof a tube Si'asbyscreW-s 3i. Extendingwthrough the tube32 is a rod 33, which, as shown bestirr-Figure 4, is anchored at its inner end "by =being1threaded into :the' .machineframe atx34; A spring: 35:isenclosedwithin the tube 32i-and reacts :Vat .oneyendx betweenthe closed end BEDi-ofthis -.tubeiandlat.its opposite end against anrabutrnent :36 secuned.tothe:-.outer end of the rod. 33 :andnheld; in positionithereon asbya nut 31 threaded onto theiouterrend .of this rod. This spring 35 thus tends to ,moventhe tube 32; and throughits connections with the pusher of the spindle-which happens;to:rbe in i the proper index positionptoi moves the pusher, also, inwardly in feeding directionw.

The retracting motion .of; the ieedztube is :produced by the actionxofa cam 38 carried-by a drum 39'securedtothe camshaft]; This ,cam 38hasa sloping cam facellfliwhich isin angular position relative: toithe' :timing of the clamping and unclampingi of the stock by the stockclamp I!) to cause the stock pusherto'be retracted duringthe'time that the collet. l0 is-in engagement withthe stock.1a This cam-'38ralso'has'a depression M which isa .second low pointofthecam, the first low pointbeing formed atithe furthest left hand portion :of 'therca'm face M which permits the spring sfii to: advance the stockpusher at a time in the cycleiwhe'n-thezcolletnll! is still closed, but whensto'ck is-in positionand in:'engag.e+ mentxwiththe stock pusher and the clamp as shown in Figure. :4, zthisiforward or feeding motion of the stockxpusherst-is prevented by "the presence'of the clamped stock which normally proper timed relation to I the other machine functionsbya vcam H5 one a HI carries a yoke: H3

IE5 of a spindlewhich is in theproperoffers such large frictional resistance to the motion of the stock pusher therealong that the stock pusher is not moved therealong by pressure of the spring 35. However, should no stock be in position to be engaged by the pusher at this time during the cycle, the stock pusher may move forwardly, as shown, for example, in Figure 8, the cam z-follower 52" fallingv intokthe cam depression 4 land should such motion occur, provision is made in accordance with this invention for responding to the out of stock conditions The particular response to this condition as shown in the present embodiment acts to stop the machines- IrkFigur-eA there is shown at M diagrammatioally 'the driving motor for the machine which normally "derives its power from the lines 45 and 46. In one of these lines, as 45, are positioned-in multiple a pair of switches 41 and 48. Thus when either of these switches is closed the motor; M is: energized, but when both .are open at: the, same time "the motor is; deenergized-iso thatthe machine-stops The switch 48' is normally closed but-is1opened whenever. the iugu50 "fixedto th'e'cam 5i of the cam shaft? is=in the angularposition of Fig. 5 such that-a cam follower roll 52 on the -.lever r53ais opposite to. the cam--depression iii". .This lever 53 has ans-end 54 connectedvthrougl'na link 55, tozra swivel head 58 carried by. the b1ock='-30,aa spring 5? being interposed between thishead 56'and a pair of nuts 59*threaded on the outerrend-iof the link 55. This; spring, .57 is". additionallycompressedby further'rockingof the vlever'53 by a suitable cam (not shown) on the-drum: ii9iafter the spring35 has-fed the stock against 'thestock; stop, in order to; prevent any rebound of the stockr-iawayfrom contact: with the stop :before the, collet; has had time to closes: Thesw-itch i47 may 'be opened by impingement on an arm $0 thereof; of a cam :element Glonqthezhub=-z62 of :the lever-:53. Whenever: the; lever: is irr,-the angular 1 position :shown in Figuresr and 'l the switch-141 remains closed, but should no-stock:be' impositionto prevent for.- ward motion tofr-the stockxpusher; whenv the .follower; 52 is a opposite .ltorthei depression 4 l which allows thelever. 53 to be. pulled in :counterclockwise direction by the action of the feeding spring 35; s the cam lug; 3'61": acts-.to open :the; switch Al. -Thus.wheneverithe shafti'l is ingangular, position toopermit actuation 1 of :the: stock feed; in "feed direction while the stock clamp is closed such action. only beingt'permitted by-ythe absence of stock in theispindle' both the switches ,48, and: ill are-opened: simultaneously so: that themachine stops.

At other timesrwhenwthecam" 33 would permitiforward feed 0f:..the stock pusher if 'no stock were in position and this motioniis spreyented by thepresence' of sto'ck being heldrby therstock clamp Hi, only the switch 48 opens. so. that. the motorgrMris still energized and continues its rotation; It will: be understood, that the opening and closing ofrthe stock-clamp l0 is-controlled by the angularrposition iof'the. cam" shaft in: a .well understood manner. The provision .ofthe roll 22 permits the: spindle tocomednto operative "relation to'theihead ZQ-Dnthestock pusher sequentially asi the spindle:carrier--1 is'indexed from one to another of itSLangular positions; there being -a stockpusherv for eachspindle, actuated byna "single spool-22 positioned at that index station where feeding of the stock is-clesired.

From :the foregoing. description of an embodiment of; this :.-invention, it should :be evident to those skilled in the art that various changes and modifications may be made Without departing from its spirit or scope.

I claim:

1. A mechanism of the class described, comprising a hollow rotary spindie through which stock may be fed, a stock clamp carried by said spindle, means for intermittently closing and opening said clamp, a rotary cam shaft, cams on said shaft for controlling operative functions of the machine including a cam for actuating said closing and opening means, a stock pusher mounted for reciprocation in said spindle and engageable with stock in said spindle, yielding means operatively connected to said pusher and tending to hold said pusher in stock-advanced position, said cams including a stock pusher cam, mechanism actuable by said stock pusher cam for retracting said pusher while said stock clamp is closed and for releasing said stock pusher to be moved by said yielding means to feed the stock While said clamp is open, said pusher-actuating cam having a second portion recessed to permit said yielding means to move said pusher in stock-advancin direction while said clamp is closed when this is not prevented by stock engaged thereby being held against feed by the closed clamp, an electric motor for rotating said cam shaft, a pair of controlling switches for said motor arranged in parallel, means actuable by said cam shaft only when said shaft is in angular position to present said pusher cam recessed portion in operative position to open one of said switches, and means actuated by advancing motion of said stock pusher for opening the other of said switches, whereby when said pusher advances while said clamp is closed both of said switches are opened to stop said motor.

2. A mechanism of the class described, comprising a hollow rotary spindle through which stock may be fed, a stock clamp carried by said spindle, means for intermittently closing and opening said clamp, a rotary cam shaft, cams on said shaft for controllin operative functions of the machine including a cam for actuating said closing and opening means, a stock pusher mounted for reciprocation in said spindle and engageable with stock in said spindle, yielding means operatively connected to said pusher and tending to hold said pusher in stock-advanced position, said cams including a. stool: pusher cam, mechanism actuable by said stock pusher cam for retracting said pusher while said stock clamp is closed and for releasing said stock pusher to be moved by said yielding means to feed the stock while said clamp is open, said pusher-actuating cam havin a second portion recessed to permit said yielding means to move said pusher in stock-advancing direction while said clamp is closed when this is not prevented by stock engaged thereby being held against feed by the closed clamp, means for rotating said cam shaft, a circuit, a pair of controlling switches arranged in parallel in said circuit, means actuable by said cam shaft only when said shaft is in angular position to present said pusher cam recessed portion in operative position to open one of said switches, and means actuated by advancing motion of said stock pusher for opening the other of said switches, whereby when said pusher advances while said clamp is closed both of said switches are opened to open said circuit.

ROGER W. BROWN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 580,539 Woodruif et a1. Apr. 13, 1897 1,591,818 Hayden July 6, 1926 2,045,486 Ogilvie June 23, 1936 2,142,557 Cone Jan. 3, 1939 2,159,398 Montgomery et a1. May 23, 1939 2,310,259 Ruppel Feb. 9, .1943 2,339,414 Kohring Jan. 18, 1944

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