US2513557A

US2513557A - Pusher

Info

Publication number: US2513557A
Application number: US760617A
Authority: US
Inventors: William P Gallen
Original assignee: Individual
Current assignee: Individual
Priority date: 1947-07-12
Filing date: 1947-07-12
Publication date: 1950-07-04
Anticipated expiration: 1967-07-04

Description

July 4, 1950 w. P. GALLEN 2,533,557

PUSHER Filed July 12, 1947 2 Sheets-Sheet 1 42 INVENTOR. 4/ W/LL/A/W P GALLE/V A TTOR/VE Y5 W. P. GALLEN July 4, 1950 PUSHER 2 Sheets-Sheet 2 Filed July 12, 1947 INVENTOR.

W/LL/A/V/ 1 GA LLEN ATTORNEYS) Patented July 4, 1950 UNITED STATES PATENT OFFICE 2,513,557 PUSHER William P. Gallen, Cleveland, Ohio Application July 12., 1947;.s'er'ial No. 760,617

'25 Claims. 1

This invention relates tostock pushers or stock feeding collets for automatic screw'machines and more particularly to improvements in the type of pusher or feed collet contained in U. S. Patent No. 2,299,972, issued 2'7 October 1942, for the joint invention of Roy R. Gallen and the applicant herein.

It is amon the objects of my invention to improve the effici'ency, life and facility of use and operation of the type of pusher contained in my said prior patent. Another object is to provide an improved and resilient stock gripping element which grips the stock with a force of predetermined a-nd/or determinable magnitude. Another object is to provide a pusher having cam means which upon the forward feeding stroke of the pusher serve to exert a cam force upon the stock in addition to said resilient force and having further means to adjust the cam force over a wide range of values in order better to meet various operatin problems such as those of stock reibound, buckling, scoring of the stock and the like. Yet another object is to provide a pusher .in which the stock gripping element can be expanded to release its grip upon the stock without removal of the element from the pusher, permitting amon other things ease of withdrawal of the stock from the pusher. Another object is to provide an improved means for removably securing the stock gripping element in operative relation to the outer body or shell element and to provide for easier "insertion and removal of the :former into and from the latter. Another ob- .ject is to reduce the number of separable operating parts in the complete pusher. Another object is to provide a permanently associated resilient locking member which in its disposition and coaction with the other elements of the pusher will effect a mutual enhancement of the strength, operation and coaction of the several related parts.

Other objects will appear from the following description of a preferred form of my invention, reference bein had to the accompanying drawings in which Figure 1 is an end elevationof' a pusher embodying my invention with its parts in assembled and operative relation; Figure 2 is a longitudinal section taken along the line 2-2 of Figure 1; Figure 3-is an enlarged view of a longitudinal section taken at 90 from the section of Figure 2, i. e., along the line 3-3-=of Figure 1; Figure 4 is an end elevation of the'she'l-l or body part which comprises the female element of my pusher; Figure 5 is a side elevation thereof as viewed along theline '5--5 -of Figure 4 and Figure-6 is the 2 opposite-side elevation thereof as viewed along the lined-6 of Figure-4; Figure 7 is anisometric view'of the resilient locking member for the bushing; Figure 8 is an enlarged view of an end elevation of the stock gripping member or -bushing part of my pusher; Figure 9 is an enlarged view of a side elevation thereof as viewed from the line 9-9 of Figure 8; Figure 10 is an enlarged view of a longitudinal section thereof taken along the line l0ll of Figure 8; Figure 11 is an enl arged view of a longitudinal section in the plane of the line I l--l l of Figure 8; Figure 12 is a longitudinal fragmentary view showing in full the adv justable shoulder within the female pusher element; Figure 13 is an enlarged fragmentary section similar to Figure 2 showing part of a modifie'd form of bushing locking finger in locking relation to the other parts of the pusher; Figures 14' and 15 are sectional views taken along the lines i i-14 and i5|5 of Figure 5 respectively;

Following the teachings "of the prior patent of Roy R. Gallenand myself the preferred embodiment of the pusher in which the instant improvements are contained comprises a hollow cylindrical body member or shell I and an inner stock gripping member 20, which for convenience I shall call the bushing part of the pusher. In their general operation, arrangement and disposition these parts follow the teaching of my prior patent particularly in that when the parts are assembled as shown in Figures 1, 2 and 3, the bushing or male part is disposed within the cylindrical bore 2 of the forward, or left end as viewed in Figs. 2 and 3, of the shell or female part, and is constrained against all but limited rotary motion with respect thereto, although it has freedom for limited relative longitudinal and/ or reciprocatory motion therein whilst the cams .26 of the bushing have sliding contact and engagement with the conically inclined cam surface 'l of the shell and are forced radially inwardly as the bushing is induced to move longitudinally inwardly of the shell to enhance the grip of the bushing (and the pusher as a whole)- upon the stock and conversely to reduce the grip upon the stock when the opposite relative movement takes place. When the bushing is gripping stock or otherwise expanded to its maximum normal workin size its external cylindrical walls have a 'free sliding fit within the bore 2 of the shell.

As is known in the art and mentioned in my prior patent the shell '1 is secured to a feeding spindle, not shown, of the 'automatic'm'achine in which it is employed by a threaded connection through the threads 'T at the rearward end of the shell, i. e., the rightward end as viewed in Figures 2, 3 and 6, and the pusher as a whole is moved bodily forwardly during the stock feeding stroke of the machine wherewith to advance the stock, not shown, that passes through the pusher as a whole and particularly through the interior of the bushing where it is engaged by the internal gripping surfaces G of the pads 22 of the bushing. It is characteristic of my patented pusher that the grip upon the stock is enhanced by the cam relationship above mentioned on the feeding stroke wherewith the stock is firmly carried forward and held against the stop of the machine until the driving collet of the machine grasps the proper length of stock exposing the proper length of the part thereof to be worked diminished grip thereupon to a rearward position from which the feeding stroke and cycle is re-initiated.

Also, each different size and shape of stock requires an appropriate and particular size and shape of gripping surface in the pusher to act therewith. In the past, excepting my prior patent, it has been common practice to change pushers as a whole with each change of stock; that is, the pushers or so-called feed fingers have had to be removed bodily from the feed spindle and replaced by difierent ones adapted to the new stock. Following the teaching of my prior patent I provide that only the bushing or stock gripping part need be replaced to accommodate a change in stock, and in my instant invention I have provided improved means to facilitate the convenience of such change. As will more fully appear below I have retained the general principle of a bayonet lock connection between the sleeve and bushing but in this invention a resilient locking finger or keeper 40, Figs. 2, 5 and 7, is secured to and longitudinally disposed in the shell and has a yielding part formed to admit the direct manual insertion of the bushing into the shell and consequent manipulation thereof to the desired removably locked and operative relation. The novel coaction of the finger 'M] with thev other parts is such that it is strong and substantially unyielding in resistance to circumferential forces arising from the tendency of the part to rotate relative to each other, and thus depart from their desired operative relation, but is readily yielding radially to facilitate the desired attachment and separation of the shell and bush ing.

Preferring to follow the teaching of my prior patent, where the same is not inconsistent with the instant invention the shell I has a longitudinally extending slot 4, see Figures 2 and 6, leading from its forward end through and beyond the zone of its camming surface I wherewith to permit the shell to yieldingly avoid bursting in the event the pressure between the cams 26 and the surface 1 tends to become excessive. The shell I also comprises at it forward end the bifurcated arrangement of overhanging lugs or extensions 3 each comprising a little less than a quadrant in circumferential extent and functioning as the female parts of a bayonet lock overhanging the cams 26, see Figure 3, when the bushing has been inserted into the forward end of the shell and turned 90 wherewith to register the cams 26 behind the lugs. The cams 26 correspondingly are of less than in circumferential extent wherewith to facilitate the entry of the bushing into the forward end of the shell when the bushing is held with the cams 26 at right angles to the lugs 3. As shown in Figure 3 and as taught in my prior patent the forward faces 21 of the cams 26 are preferably inclined rearwardly from the radial plane to coact with complementarily inclined cam surfaces 8 on the rearward faces of the'lugs 3 so that engagement between these surfaces on the rearward stroke of the pusher will tend to expand or at least not contract the bushing. In the operative relation of the parts the maximum diametrical span of the cams 26 exceeds the minimum diametrical span between the inner surfaces of the lugs 3 wherewith the parts are retained in the bayonet locking relationship taught in my prior patent.

The shell I has its main rearward cylindrical bore 9 smaller than the bore 2 but of a diameter large enough to permit the free movement therethrough of stock of maximum capacity leaving a relatively thick walled portion of the shell in the rearward part thereof which terminates in a threaded portion 5 adapted to receive a sleeve M which acts as an adjustable stop against which the rearward end of the bushing 20 abuts at the limit of its extreme longitudinal inward movement. As taught in my prior patent the shell is preferably made of appropriate quality of steel susceptible of being freely machined to give it the configuration described and also susceptible of being hardened in the zone of the cam surface 1 adjacent its forward end but also tempered to a desirable degree of resiliency rearwardly of the cam surface 7 and particularly throughout the zone of the slot 4 wherewith to combine both desirable wear resistant characteristics in the cam surface and desirable resilience of the adjacent structure to permit the expansion of the cam surface 1 under at least extreme load.

The bushing 20 follows the teaching of my prior patent in recognizable respects including its general coaction with the shell and in its general form and contour, with stock gripping pads 22 relatively movable radially with respect to each other wherewith to grip the stock along the internal gripping surfaces G thereof. The bushing 20 integrally includes a rearward ring portion 2| integrally joined by diametrically opposed and spaced parts 32 to the pad portions 22 wherewith to give the pads an inherent tendency to have an initial resilent grip upon the stock to be pushed prior to receiving aid from the action of the bushing cams 26 on the surface cams l of the shell. The longitudinal lengths of the resilient ring 2| may be proportioned to the length of the pads 22 about as shown in the drawings, and the circumferential lengths of the parts 32 may also be proportioned as shown having regard for the desired resilient strength sought from the ring 2| and the parts 32. It is desirable, however, that the thickness of the ring 2| shall not materially impair the capacity'of the pusher with respect to the maximum diameter of the stock to be fed thereby. Similarly the radial dimensions of the pads along with the shape of the gripping surfaces G may be accommodated to a wide variety of shapes and sizes of stockup to the point where the thickness of the pads-does not substantially exceed the thickness of the ring 2|. In these forms of bushings in which the pads 22 are thicker than the ring 2| I prefer that the rearward ends of the pads merge into the ring a" chamfered or conical 8 junction betweem the rihg'..an1d the pads whereby to enhance the? strength of bond therebetween zas welt aszntazaiford. a;:guide-. for the end of the stockto be. receivedltherein: As shown in: the-drawings the: pads. are greatly thickenedwith the surfaces G cylindrical-inform wherewithl to engage roundzstoclc'iof mucnsmaher diameter than the largest size stock. that might be accommodated inapusher combinationcomzprising the same shell: and.a different internal sizeof bushing with thin. padshaving thegripping surfaces G correspondingly enlarged; The bushing as a whole is' preferably made of that kind of steel in which the pads .andwparticularly the gripping surfaces .Gthereof may be hardened for the sake of long wearand. the -ring;portion 2| and parts 32 thereof may beappropriatelyspring tempered where-with togive it the desired resiliency for the purposes abovezdescribed. 'I do not exclude other materialsthat may be used to better advantage with regard to; the: different kinds of stock upon which my pusher mayoperate that retain the essential characteristics and mode of operation thereof. As more fully .ex-

plained in my prior patentit is advantageous to have in mind that the qualities of the material of thebushing and the shell and theh'ardnessor relative hardness of the parts that :have the camming action on the .one handand-the stock gripping function on the other hand bears upon a not only the wearing qualities of such .parts but the co-efiicient of friction of suchparts in] relation to each other and to the stock to be pushed. Due regard for these considerations for their bearing upon the inclination of the cammingsurface 1, the contour of the faces of'the cams 25 and the quality andhardness of -the;parts. with regard to the form, shape andquality-of the stock to be pushed will behad by those skilled in the art within theteachingsof this specification and my prior patent.

The pads 22 and the ring portion 2| are defined by a pair of-identical T-shaped-slots, each comprising a longitudinally extending slot 3.0

separating the pads 22 and comprising'the legof the T, running throughout the lengthof the pad portion of the-bushing and terminating in a transverse slot 3| disposed as the head ofthe T. The transverse slots 3| preferably extend substantial circumferential distances around the bushing and separate the adjacent part of -.the ring portion 2| from the adjacentgparts of the pads 22 throughout the*circumferential extent of the slots 3|. Thus the ring part 2|.is joined integrally with the separate pads 22 only. for the limited circumferential extent in the parts .32, see Figures 10 and 11, that lie between therespective-ends of the .transverseslots -3|. For reasons presentlyto be discussed it is preferable that the slots 3| have a width or longitudinal extent a little greater thanthe diameter of .a tenpenny nail or similar smallvinstrumentality;

The bushing is-preferably. hardened with the pads 22 held closer-togetherthantheir relative position when gripping stock with the result. that the bushing pads must be forcibly sprun'g apart when stock is inserted. The bushing-is illuss trated' in the drawings inits sprung apart" condition although in the absence ofstockenibraced therein the s1ots30 wouldpreferably berclosed or substantially narrowed-at the end of the bushing remote from the ringfiportioh 2|. insofar .as the :bushing alone is involved the stockis gripped with a force determinedby several factors, the resiliency per seofi'thez ring: 2 t and parts-"Bums angular circumferential length of the parts .32 and the. heat; treatment: to which. they are sub.- -jecte.d.. The desired resiliencycan-in partibe obtained: by properly spacing; the pads of the bushing duringthe hardening treatment and then-drawing the ring portions 2| and adjacent parts-32. back to, the required resiliency. A second factor, the angular extent of theparts32; is determined by the length of the slots 3|. When the. pads are sprung apart the parts 32 are 'stres'sedasis also the ring 2|, the parts 32 tend ingzfirstxto be flattened and then bent outward with the ring tendingto assume a slightly ellipti cal formand =by'resisting such distortion lending support to the.parts32. The parts 32 backed up by the ring 2| in this manner function like springs acting in opposition to the diametrical .openingmovement-of the pads. The greater the circumferen-tialilehgth of the parts 32 the greater is the'forcewith which. they will resist-the flattening and bending forces and necessarily the greater will be the resilient force with which the bushing gripsthe stock. If it is desired to reduce the stock-gripping force, the slots 3| may be elongated, reducingthe arcuate length of the parts 32 making them notonlyshorter but also relatively flatter and hence less resistant to the opening forces exerted bythe stock.

My bushing design thus enables the bushing to flex with a determinable resiliency as the pads move-diametrically to. and away from each other with a comfortable margin of safety, controlling accurately the desired action of the pads, and extending the life ofthe bushing and pusher.

The resilient grip of the bushing upon the stock augmented and/or modified by the cam action previously described. In the feeding stroke of the pusher, the forward motion of the hell will'lea'd the corresponding movement of the bushing so that the bushing is given a rearward movement relative to the shell. The cams 2'6 of the bushing will therefore be influenced by the cam surfaces 1 of the shell in a manner to :cause the pads to move radially inwardly'to grip the stock with added force. Thus the total gripping force of the pads on the work during the feeding stroke is the algebraic resultant of two components, the inherent resilient spring force of thebushing and the component resulting from the coaction of the cams.

'I also find it desirable to control the latter component, thecamforce, by limiting the rearward longitudinal motion of the bushing relative to the shell; the yielding of the camsurfaces 1 as permittedby the slot 4 as more fully described in said prior patent preferably being preservedwith the operation and means about to be described. Tothis end I provide an adjustable threaded's-leeve H] which is secured within the shell] and which acts as an adjustable stop or shoulder-toward or against whichthe bushing moves or abuts =in its rearward movement or rearmost-position relativeto the shell. Preferably-the sleeve til substantially matches the ring portion Has to internal diameter and wall thickness-so as not 'to reduce the capacity of the pusher, and has anexteriorly threaded portion adapted to :engage the female threads i-of the: shell. Both sets of-threads-are as shallow aszis consistentwith their function and areas longas' necessary for strength, The threaded portion of the sleeveri-is :'-p1-eferably a few thou 'san'dlths oversize as-compared-"wit-h the-shell and is preferably split by -a longitudinal slot la 30 asto have: a: snug resilient fit with the threaded a ea-3355!:

.7 portion t of the shell. However, I alsoprovide additional means to insure that the sleeve will remain locked in the desired position of adjustment, which means preferably takes the form of a resilient locking finger l adapted to cooper.- ate with longitudinal retaining grooves l2 in the sleeve and so secure the sleeve against accidental displacement.

The locking finger liis the shell by press fit within a longitudinal dove.- tail groove [6 substantially in the manner later to be described in reference to the main locking finger 4B. The dovetail groove 16 is shown to be substantially in alignment with the slot 4, see Figure 6. The free end of finger. l5 normally lies within an aperture H in the wall of the shell, see Figure 6, of substantial size, and in locking position, extends down into one of the juxtaposed longitudinal grooves lz see Figure 12, of. the sleeve to hold the sleeve against turning movement. These grooves 42 are preferably shallow being just deep enough to-receive the finger and enable it to hold the sleeve against rotation and are spaced circumferentially of the sleeve as shown in Figure 12. In order to release the sleeve for adjustment the finger canbe lifted by a nailor other sharp pointed instrument applied to the finger in a lifting movement.

The aperture i! not only permits the finger IE to be readily unlatched but also gives access to the interior of the shell and to the sleeve so that the sleeve can be adjusted as desired. To enable such adjustment I provide a number of equally spaced perforations l3 disposed circumferentially of the sleeve as shown and preferably staggered with respect to the longitudinal grooves Ill. The aperture H has sufficient circumferential length to expose at least two of such perforations. The position of the sleeve can be adjusted by first lifting the finger l5 to unlatching position and then turningthe sleeve by applying torque with a pin inserted within one of the exposed perforations.

Other means of locking the sleeve in in the desired position may be used. I also find it convenient to lock the sleeve in place by a lock nut arrangement in which the sleeve is made in two parts as indicated by the dotted lines in Figure 12. The forward part I to may or may not have the grooves 12 as preferred but in any case it still retains the holes [3 for purposes'of adjustment. The rearward part ND is preferably threaded over its whole length and it also is provided with holes l3a, shown in dotted lines, for adjusting, the holes [3a. being accessible through aperture Ha, shown in dotted lines in Figure 6. The part I la is first positioned so as to limit the rearward movement of the bushing as desired, and the part llb is then screwed tightly up against it to hold it locked vagainst displacement;

The facility with which I can thus adjust the cam force finds utility in many instances. The sleeve I0 can be moved forwardly to so restrict the movement of the bushing as to substantially eliminate coaction between came 26 and I allowing only the resilience of the bushing to grip the stock. screwing the sleeve to its extreme forward position and thereby forcing the bushing to its extreme forward position will effect coaction between

cams

21 and 8 and correspondingly open or spread the pads of the bushing to relax correspondingly their resilient grip on the stock. In the rearmost position of the sleeve the bushing will have full rearward movement within the shell with the cams exerting their, full influence the preferably secured limit of which: is-determined 'by the resiliency of the split shell as more fully described in my prior patent. In intermediate positions of the sleeve It the cam force may be limited or modified as desired. For example, if my pusher is properly adjusted for a run of stock of particular size and material with thesleeve It) in a particular midposition then it may well be that before the end of a long run wear of the cam surfaces or other normal wear may reduce the desired grip on the stock. In that event a modestrearward movement of the sleeve in permitting more travel of the bushing relative to the sleeve will compensate for such wear and bring backthe desired grip and feeding operation and effect. Other examples will be recognized and may be cited. For instance one day one of my pushers may be used at full capacity with, for example, a run of 1" diameter hard steel stock wherein the bushing therefor will be chosen to have the relatively high resilient grip and the sleeve [0 will be moved rearwardly for substantially a maximum cam force for efficient and positive feeding of the-stock. The next run on the same machine may be with diameter light aluminum rod or tubing requiring a very different treatment by the pusher for satisfactory feeding. In that instance the resilient grip of the bushing may be chosen to be light enough to avoid scratching or scoring the surface of the stock while firm enough to provide merely the inertia wherewith to bring thecam action into play in a desirable amount at the beginning of and on the feeding stroke. However the very lightness of the stock requires but a limited gripping force for satisfactory feeding movement thereof and a light grip permits desirable but controlled slippage after forcible contact between the stock and the stop of the machine has been made to avoid either upsetting, bending or otherwise injuring the length of stock between the pusher and the stop especially in machines having a, positive and unyielding pusher feed. In such an instance forward adjustment of the sleeve ID of my pusher taken with proper selection of the bushing very readily facilitates the application and limitation ofthe forces and effects most desirable for the purpose to'which they are employed so that the very light and weak stock may be handled in one run with the same desirable efiiciency that tough and heavy stock may be handled in apreceding or following run.

The adjustability' of the cam gripping force taken with the adjustable determinability of the bushing gripping force, the ready exchange and substitution of one bushing for another and the protection against injuriously high pressures afforded by the slot-4 taken in their whole or partial interplays and coactions gives my pusher a wide range of utility and efficiency, ready compensation-for' wear and high protection against injury either to the pusher or its parts or to the stock upon 'whichit-operates. i

As shown particularly in Figures 9 and 11 the portion of the slots 3!! of the bushing adjacent the slot 3! ismi-lled out to form a longitudinal groove 33 of slightly greater Width than the width of the finger 48 and, as shown, to a greater Width than the slot 30. The depth of the groove 33 is preferably in'excess of the depth of the thickness of the ring part 21 and-in all events is of such depth that its .depth plus the thickness of the adjacent wall of the shell, Figs. 2and 15, exceeds the overall. thickness of the end 4! of the finger 4.0-. Thus when'the freeend 4| ,of the finger 40 isreceivedin the groove.33. no-partof the. finger:

is required to lie above the cylindrical exterior surface of the shell, 1, see also'aFig. 13. As shown in Figures 2, 7 and 13 the forward endsof either form of the bushinglocking fingers have depressed or-thickened portions the lower parts of which are adapted to lie within the lateral confines of the groove 33 with a freedom of fit-there- With that permits the free longitudinal sliding movement of the bushing with-respect theretoand with respect to the shell I when the pusher is in operation. Thus the longitudinal extent of the part of the finger lying in the groove is one of the measures of the required length of the groove 33; the length of the groove 33 taken with the width of the adjoining cross slot 3| preferably exceeding the length of the part of the finger in the. groove by an amount at least equal to the desired longitudinal travel of the bushing within the shell. tent of the slot 3| should not so exceed-the length of the thickened or depressed end of the finger to permit the end of the finger to become disengaged from the groove 33 by the mere longitudinal forward motion of the bushing with respect to the shell. While I have mentioned; the depth of the groove 33 having regard to the bottom of the sides thereof adjacent the slot 30 it will be appreciated that in bushings in which the pads 22 are of reduced radial dimension the groove 33. may be bottomless in the sense that it may .cut :all the way through shallow pads.

The locking finger "40- is disposed to lie ,longie tudinally of the pusher and radially within the cylindrical exterior surface of the shell I,. To this end the shell I, seeFigure 5, preferably on the side opposite the slot 4 is grooved as-at 43 lengitudinally and external-ly from a point just forwardly of the rear of the threaded portion 5 to a point about half way to a circumferential slot-5.0 as shown in Figure 2. From this point a slot 44 extends in alignment with the groove, intersects the slot "50 and extends beyond it for ;a length. The slot-.44 as will be described later perm-its the locking finger to reach within the sleeve-andengage the bushing. The groove 43 is undercut Ion,- gitudinally preferably along both sides to form a dovetail groove, .see Figure'M, which receives the shank of the locking finger 40 in tongue and groove engagement. The depth of (the groove is preferably equal to the thickness of the wallof the thin walled forward portion of the shell and thelocking finger iszthinnerso that it may be received'therein. In order to insert the finger within the groove itsturnedor-beaded end "4 l isfiexed upwardly-sothat room .willbe, had tolena-ble the shank end Ito be fitted into the open end of the dovetail .groove, the finger is then forcibly ,inserted fully into the groove. The locking end of the :finger thereafter --is released and allowed :to move downwardly-into the slot taking its normahpositionas shown in Figures 2, 5, 13-and 15. Preferably'the shankend of'thefinger-is milled to fitzsnugly within the :groove as shown. The finger is self retaining under normal-operating conditions. In order to remove the finger, the locking-end'must first be flexed so that it canclear the forward endof the slot 44, and thenithe rearward half of :thefinger can'be driven out ofthe dovetail groove. Such .a sequence aof operations is practically impossible to obtain-by chance ;or mischance" under 5 operating conditions, yet if the finger should break or .wear-it'can readily be driven out and replaced. When the rearward or shank "p rtioniof the :ifineerzis iu yin ert dint groove 43 the. {forward port n zthcre fwwilh ie l i Correspondingly the longitudinal ex- '10 the slot ,44. and; the whole finger will lie below and within the cylindrical external surface of the shell. The-locking finger 4,0 is preferably wider than it is thick, for a shel=1.ofabout 1" external diameter being about 3% thick and about wide. The, finger is preferably made of stron spring tempered steel wherewith to be highly re,- sistant to bending transversely of its width while fairly free to bond transversely of its depth. The slot 44' will preferably exceed the width of the finger only by an amount permitting the forward end of the finger to have freedom of movement within the confines of the slot. The forward portion of the finger which is preferably about half the length thereof will lie in the slot 44 with its free end 4| freely spaced from the forward end of the slot 144-to permit the free forward portion of the finger .to be raised upwardly against the inherent resistantyielding thereof. 'In the form of finger illustratedin Figures 2; and 7 a short length 42 is turned downwardly and rearwardly wherewith to give somewhat more than double overall depth to the ex ernalforward end portion and alsoto. give an upwardly and forwardly inclined and rounded face to the end of the fingerwhich, when-the finger 'liesin its normalunstressed position', as shown in Figures 2 and 13, prior to the insertion of the bushing into-the forward end of the sleeve, will afford an inclined surface of contact with the outer rearward corner of the ring 21 of the bushing whenthe bushing first makes contact therewith, and which will enable the end of the finger ;to be easily lifted permitting the ring of the bushing to pass thereunder as the shing i ecl- W e t e fi r takes he form 40a shown in-Eigure 13 its forward end may be merely offsetrand curved as at 46. wherewithto ve; it exte n q wa d end suc an effective overall depth-or thickness as to enter and subtantially-reachthe bottom of the groove 33 preferably contacting thebottornthereof asat 41. In this, form-the fingeralso hasan upwardly sloping and forwardly inclined facei48 thatmay be slidably rand yieldably I engaged by the outer rearward corner of the ring .21 upon the intial insertion of the bushing into the sleeve for the purposes and with the results above described with respect to the-rounded fOIQWB id'BIlQ-OFHIS finger 40.

Referring particularly to Figures 5 and :113 it will-be seen that I have provided a transverse slot out through the wall of the shell-about midwayof the length (of the slot 44 and preferably disposed "to lie just a little rearwardly of the thickened orldepressed part of the forward end of the fingers-4,0 or 4n This slot is preferably bu h tl w d n e h di met of a en-pe y nailin theinstanceiof-a-pusher ofv about'the size bo e-mentioned, and-this-slo ois limited in its circumferentia exten whe y-to not su a tiallyexceed a distance which would permit the freeinsertion of anail or other small pointed'instrumentality :underneath the adjacent part .of the forward flnd'of the locking finger so that the nail or-similar instrumentality may be fulcrumed upon eitherre dnf th fi ofiwherewith t'o :lift'the hiqls neder rde re se for ardend of e fi er u i ou 0 hee oo 10 e ush ng to p rm t theibush neto-t turne w t ionto the shell. In practice -;especially when the sleeve is rigidly securedtothe cylindrical feed.v Spindle the me e nsertion o .the n c t e nail in the 5101;

50 and {th manual depression thereof by the them zer fin e c one hand re di y. di n ases the -;end of the fing er -;from the groove ,33 whilst eacher-handssvfreei r steep-the; ex rn l for- '11 ward end of the bushing and'turn it 90' whereby to rotate the cams 28 from behind the rearward faces of the lugs 3 and extract the bushing. The insertion of a bushing is even more simple since this requires merely that the bushing be held in axial alignment with the shell with the cams 26 at right angles to the lugs 3 whereby to pass therebetween. Then gentle but forcible movement of the bushing rearwardly will liftthe end of the finger by sliding contact with the outer rear corner of the ring 2|. Further rearward movement of the bushing bringing the forward faces of the cams 26 behind the plane of the rearward faces of the lugs 3 will cause the forward end of the finger to come to bear upon the smooth outer surface of the'bushing rearwardly of one or another of the earns 26 and preferably somewhat forwardly of the plane of the front edge of the slot 3|. Thereupon a 90 turn of the bushing will bring the groove 33 of the bushing into radial N alignment with the slot 44 of the shell and with of my pusher and the semi-permanent attachment of the resilient locking finger to the shell means in effect that when the shell is attached to the feeding spindle the operator of the machine has but a single element to deal with, to wit, the bushing. In effect when he desires to change pushers to accommodate different stock or to replace a worn bushing he has merely to remove one bushing and replace it with another requiring for that operation merely his hands and a tenpenn mail or the like. The finger is neither flexed nor is there any tendency to flex it transversely of its minor dimension when the pusher is in use and is ordinarily loaded but transversely of its width wherein it has ample strength to resist such loads through a long life especially since it is supported laterally throughout the greater portion of its forward free length by the side walls of the slot 44 with which it has free sliding contact closely adjacent the side walls of the groove 33, see Figures 13 and 15. The free length of the forward end of the locking finger is such I of the finger, i. e. move it radially outwardl of the groove 33. This tendency, however; is limited to a matter of harmless degree in my invention since an uppermost part of the free end of the finger, as for 'exampl'ethe corner 49 of the finger 40a, will in idle position lie substantially flush with the outer cylindrical surface of the shell with the result that radially outward movement of the free end of the finger in an amount substantially'less than the depth 'ofthe groove 33, i. e., substantially less than the most thickened or depressed part of the finger lies within the groove 33, will bring contact between the point 43 and the interior surface of the closely adjacent collet driving spindle before any sub- 1 stantial part of the finger that is intended to lie within the groove 33 will move therefrom.

Since the coaction of the cam surfaces 1 and 26 permits relatively easy movement of th stock forwardly in the pusher, but properly resists realward movement therein I have made provision in my pusher to facilitate rearward withdrawal of the stock from the pusher when the same is nec-' essary or desirable. To that end I provide for holding the bushing forwardly to inhibit the cam action and/0r inhibit the cam action and expand the bushing. Advancing the sleeve Ill forwardly to effect coaction of

cams

21 and 8 does both things and is especially practicable where maximum freedom from the grip of the bushing pads upon the stock is denied. A straight rearward pull then easily removes the stock. I also provide for a similar effect without moving the sleeve [0 by locating the forward edge of the aperture I1 far enough forwardly to provide access to the rear edge of the bushing. A screwdriver or similar tool can thus be inserted through aperture I1 and between the rear end of the bushing and the forward end of the sleeve [0 to force the bushing forwardly and hold it there while the stock is withdrawn rearwardly.

While I have illustrated and described a preferred and modified form of my invention, changes, modifications, adaptations and improvements thereof and thereon will occur to those skilled in the art who come to understand and appreciate the teachings hereof and the principles and advantages of my invention wherefor I do not care to be limited in the scope of my patent to the forms and embodiments of my invention herein specifically disclosed nor in any manner other than by the claims appended hereto.

I claim:

1. A stock feeding pusher comprising a female shell member, a male stock gripping member rotatably movable therein for insertion and removal therefrom and longitudinally movable therein, coating cam means carried by said members responsive to relativelongitudinal movement therebetween for modifying the gripping force of said male member on the stock, means for restraining said male member against rotatable movement while permitting longitudinal movement relative to said female membenand a sleeve adjustably carried by one of said members and coacting with the other to control 10ngitudinal movement therebetween.

2. The combination of claim 1 with means for locking said sleeve in a determinable adjustable position.

3. The pusher of claim 1 in which said sleeve is locked in its adjusted position within said female member by a separately operable abutting threaded sleeve serving as a lock nut therefor.

4. The pusher of claim 1 wherein said male member is split by a pair of diametrically opposed T-slots defining two stock gripping pads and a resilient ring connected to said pads by arcuate resilient connecting portions,

5. A stock feeding pusher for automatic screw machines or the like comprising a female shell member and a removable and replaceable male stock gripping bushing longitudinall movable therein, said bushing having inclined cam portions, said shell having complementary cam surfaces adapted to coact with said cam portions upon relative longitudinal movement of said bushing within said shell to increase the force with which the said bushing grips said stock, and adjustable means for selectively limiting movement of said bushing relative to said shell and to modify the coaction of said cams.

6. The pusher of claim 5 in which said adjustab e means t ke the form of a sleeve threadedly mews secured within said shell: adjacentthez-rearward end of said'bushing and adapted to abut-thereagainst.

'7. The pusher of claim'fi in'whichrsaid sleeve has a plurality of circumferentially spaced recesses and saidshell'has'a resilient locking finger secured thereto, said 'iinger having a :portion adapted to 'seatin one of 'said' recesses and secure said sleeve against rotational movement, said portion being yieldably removable fromsaid recess to permit said rotational movement.

8. A stockfeeding pusher com'prising'a' female shell memberand a male stock grippingbushing longitudinally movable therein, said bushing having-a pair of diametrically opposed 'T-slots defining two stock-gripping padsand a resilient-ring connected to said pads by arcuate connecting portions whereby said bushing'has a resilientgrip upon the stock to be'fed, each of said pads having an externalra'dially projecting inclined cam portion, said shell having interior complementary cam surfaces adapted to coact with said cam portions upon relative longitudinal movement between said shell and said bushing.

9. The pusher of claim 8 with means for adjustabl positioning said bushing relative to said shell.

10. In a stock feeding pusher for automatic screw machines and the like, a male stock gripping taking the form of'a bushing split by at least two T-slots defining aplurality'of stock gripping pads and a resilient ring connected to said pads by resilient arcuate connecting portions whereby said bushing has a resilient grip upon said stock.

11. In a stock feeding pusher having a female shell member and a male stock gripping member longitudinally movable therein, means for removably restraining said members from relative rotational movement while permitting relative longitudinal movement comprising a longitudinally extending resilient locking finger having one portion fixedly secured in one of said members and another portion slidably engaging the other of said members between spaced radial surfaces thereof, said other portion of said member being yieldably removable from between said surfaces to permit relative rotation therebetween.

12. In a stock feeding pusher having a female shell member and a male stock gripping member longitudinally movable therein, means for removably restraining said members from relative rotational movement while permitting relative longitudinal movement comprising a longitudinally extending resilient locking finger having one portion fixedly secured in one of said members and another portion circumferentially supported in said member and slidably engaging the other of said members between circumferentially spaced surfaces thereof, said other portion of said member being yieldably removable from between said surfaces to permit relative rotation therebetween.

13. In a pusher having a shell member and a bushing member interlocked for limited longitudinal movement in one angular relation and separable in a different angular relation, the improvement that the shell member and bushing member have longitudinally extending grooves adapted to register when said members are in interlocked angular relation and a, longitudinally extending locking finger secured in the groove of one of said members and having a yielding part entering the groove of the other of said members, the end of said yielding part being rounded, and said other member having a portion angularly spaced from said groove and slid- 1'4 ably engageable with the roundedend of said finger for flexing the latter when said members are assembled.

14, A pusher according to claim 13, in which said shellimember and bushing member have circumferentially extending slotsrespectively intersectingsaid-grooves and adapted to be substantially align-ed when said'me'mbers are in interlocke'dangular relation.

'15. In a'pusher havinga shell member and a bushing member adapted for limited longitudinal movement in one angular relation and separable in a diiTerent angular relation, the improvement that the shell member and bushing member have longitudinally extending-grooves adapted to be registered when said members are in one angulari relation and a longitudinally extending locking finger secured in the groove of one of said members and having a yielding part entering the= gro'ove..of the other of said members, and said other ipartshaving a portion angularly spaced from said groove and slidably engageable with saidfingerforffiexingthe-latter when'said members'areiassembled.

::1*6.=A;ipusher of the class described comprising a-zfem-a'le'sleevesmember and a male stock grippingimember, said 'female member having a rearward wall portion and forward wall portion adapted to receive'the male'member at the for- Ward-end, said rearward portion having a longitudinal dovetail groove and said forward portion havinga longitudinal slot connected with said groove and a circumferential slot intersecting said longitudinal slot, a resilient finger lying partially Within said groove and lying partially in said longitudinal slot and extending interiorly through said slot, said male member comprising a bushing having at least two T-shaped slots whereby to define a plurality of stock gripping pads and a resilient ring integral therewith, the head and the leg of one of said T-shaped slots being adapted to register with said circumferential and longitudinal slots respectively of said sleeve member whereby a part of said finger may lie in both said longitudinal slot and the leg of said T-shaped slot and traverse said circumferential slot and the head of said T-shaped slot.

1'7. A pusher of the class described comprising a female member and a male stock gripping member, said female member having a rearward threaded portion adapted to receive a threaded sleeve and having a forward portion adapted to receive the male member, said forward portion having a longitudinal slot, a longitudinally disposed resilient finger attached to said female member and overlying the end of said sleeve and lying partially in said longitudinal slot and partially extending interiorly through said slot, said male member having a slot adapted to register with the longitudinal slot of said female member and receive a portion of said resilient finger when said stock gripping member and female member are assembled, said sleeve limiting inward movement of said male member into said female member whilst said finger resists relative circumferential movement therebetween.

18. A shell or female element of a stock pusher of the class described, adapted to receive a stock gripping element for relative movement therein, having a longitudinally extending slot in the Wall thereof extending into the zone of the shell to be occupied by the stock gripping element, and a finger fixedly secured in the said wall beyond said slot and having a resilient part in said slot with a portion extending inwardly of the interior 1 22. The shell element of claim 21 with a second finger carried thereby and coacting with said sleeve and releasably securing said sleeve in adjusted position.

23. A female sleeve member for a pusher of the class described comprising a thick walled portion at one end and a thin walled portion at'the other end, said thick walled portion having a longitudij nal exterior dovetail groove of depth substanitially equal to the thickness of said thin walled portion, said thin walled portion having a longitudinal slot connected to said groove, and a resilient finger having a dovetail part disposed in said groove and another part in said slot, said finger occupying substantially the full length of said slot and being irremovable from said groove except upon flexure from said slot.

24. A female member for a stock pusher of the class described having an internally threaded p0rtion,"an externally threaded sleeve disposed entirely within said threaded portion and having intermediate the ends thereof circumferentially spaced apertures to facilitate rotation thereof, said member having an overlying aperture exposing the apertured portion of said sleeve and extending circumferentially at least as much as the circumferential spacing of the apertures insaid sleeve.

25. The combination of claim 24 with a male member removably secured in said female member forwardly of said sleeve, cam means carried by said members which tend to expand said male member upon forward movement thereof, said female member being apertured adjacent the proximate ends of said sleeve and male member to admit insertion of a tool therebetween to force said male member forwardly.

WILLIAM P. GALLEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number