US2345207A

US2345207A - Stock feeding mechanism

Info

Publication number: US2345207A
Application number: US347935A
Authority: US
Inventors: Judson H Mansfield
Original assignee: Greenlee Brothers and Co
Current assignee: Greenlee Brothers and Co
Priority date: 1940-07-27
Filing date: 1940-07-27
Publication date: 1944-03-28
Anticipated expiration: 1961-03-28

Description

March 1944- I J. H. MANSFIELD 2,345,207

' STOCK FEEDING MECHANISM 7 Filed July 27. 1940 s sheets-sum! 1 Q4 @4972: v ([LdiSomjy March 28, 1944.

J. H. MANSFIELD s'rocx FEEDING MECHANISM Filed July 27, 1940 5 Sheets-Sheet 2 IIIII/IIIXIIIA Judson L. r/zey lax/111111) A March 8, 1944. J. H. MANSFIELD 2,345,207

STOCK FEEDING MECHANISM Filed July 2'7, 194 5 Sheets-Sheet 3 March 28, 1944. J. H. MANSFIELD 2,345,207

STOCK FEEDiNG MECHANISM Filed Juiy 27, 1940 5 Sheets-Sheet; 4

March 28, 1944- J. H. MANSFIELD ,345,207

I s'rocx FEEDING MECHANISM v Filed July 27, 1940 v 5 Sheets-Sheet 5 4.. Ifvagq.

Patented Mar. 28, 1944 STOCK FEEDING MECHANISM Judson H. Mansfield, Rockford, 111., assignor to Greenlee Bros. & (30., Rockford, 111., a corporation of Illinois Application July 27, 1940, Serial No. 347,935

18 Claims.

This invention relates to a stock rack and feeding mechanism designed to serve an automatic machine, and it is herein shown and described as associated with and partly included in an automatic screw machine.

One object of the invention is to provide a mechanism having an improved form of intermittently operating feeding means for advancing a relatively long piece of stock to a machine in which it is to be worked up and cut into shorter pieces which constitute the product of the machine.

Another object of the invention is to provide a feeding mechanism adapted to handle substantially any length of stock up to a maximum.

A further object is to provide a stock feeding mechanism in combination with a stock supply rack equipped with means for automatically transferring a length of stock from the rack to the feed mechanism when required.

It is also an object of the invention to provide a stock feeding mechanism associated with a machine having a chuck or gripping device through which an excess length of stock is fed at each operation, the machine including means for then reversely moving the stock by a distance suflicient to insure that an adequate length thereof will be engaged in the chuck or gripping device.

And it is also an object of the invention to provide a stock feeding mechanism for advancing a length of rod or tubing into a machine by reciprocating feeding means which includes a yielding feed member engaging one end of the length of stock and a fixed stop against which the other end of the stock is fed so that less than the full stroke of the feed mechanism may be utilized by adjusting the position of the stop without altering said stroke of the mechanism.

More particularly it is an object of the invention to provide a stock feeding mechanism which includes a guide trough or channel for a length of stock, a reciprocatory feed bar mounted alongside the guide and having a plurality of fingers extending laterally at intervals so that said fingers may successively engage the end of the stock as it is advanced along the guide by reciprocation of the feed bar, together with a rack for reserve stock adjacent the guideway, and automatic means for releasing additional stock to the guideway whenever the length of stock therein passes a certain point adjacent the machine to which the stock is being supplied, the mechanism including means for periodically lift- Figure 1 is a side elevation showing a portion of an automatic screw machine and a stock feed mechanism embodying this invention, a portion of the feed mechanism being broken out to condense the view.

Figure 2 is a plan view corresponding to Figure 1.

Figure 3 is a detail section on a larger scale taken as indicated at line 3-3 of Figure 2.

Figure 4 is a detail section taken as indicated at line 44 on Figure 2.

Figure 5 is a detail section taken as indicated at line 55 on Figure 2.

Figure 6 is a detail plan view of certain portions of the mechanism shown in Figure 5.

Figure 7 is a fragmentary side elevation showing parts of the drive connection between the screw machine and the feed mechanism.

Figure 8 is a detail vertical section taken substantially as indicated at line 88 on Figure 9.

Figure 9 is a transverse detail section taken substantially as indicated at line 99 on Figure 1.

Figure 10 is a diagrammatic vertical section taken substantially at line l0l0 on Figure 2 to show the drive connection for the automatic stock supply mechanism.

Figure 11 is an enlarged detail elevation of a stock guide adjusting device.

Figure 12 is a fragmentary plan view of the stock feeding fingers.

While the invention is disclosed in the drawings and will hereinafter be described as embodied in a preferred form, it is not intended that the invention be limited to the specific structure herein disclosed. It is the intention to cover all modifications and alternative constructions falling within the spirit and scope of the invention as defined in the appended claims.

To facilitate an understanding of the invention as herein illustrated, it may be explained that the automatic machine with which the stock rack and feed mechanism is shown associated, is designed for the production of threaded pipe nip.- ples and includes duplex mechanism whereby the machine produces two units of the product simultaneously. This involves the provision of two hollow spindles I, l mounted parallel to each other in the head 2 of the machine. The tubular stock from which the pipe nipples are to be made is fed into these spindles and gripped by suitable collets therein, with a portion projecting from each spindle in position to be worked upon by the various tools in a well understood manner. After certain operations have been performed on the portions of stock projecting from the spindles I, I, these portions are cut oil and transferred to a second pair of spindles 3, 3 mounted in a head 4 of the machine opposite the head 2; this permits threading and completely finishing both ends of the nipples.

When the stock is first advanced through. the spindles I, I it is over-fed by about three quarters of an inch into engagement with a stock stop 5 mounted in the head 4 of the machine; thereupon the member 5 is automatically reciprocated to push back the stock by the amount of the overfeed before the cutting tools move into position for working upon it. This insures that. there is a safe length of stock to be gripped by the chuck or collet in which the material is held while it is being machined; if there is less than threequarters of an inch of this extra length in the piece when it is fed against the stop 5, it will simply drop out of the machine instead of being pushed back into the collet of the spindle I, thus avoiding the danger of accidents which might otherwise occur. Since the over-feed and reverse movement of the stock takes place before the nipple lengths are cut off in the machining operation, the reverse movement affects the entire length of the piece of material extending back into the stock feed mechanism and requires that the latter be designed to allow for it.

The stock rack and feeding mechanism is supported at one end by a special bracket 6 mounted upon and attached to the base of the screw machine, and at a distance from the machine suitable legs' 8 are provided near the remote end of the feed mechanism and also at intermediate points, if its length requires such supplemental support.

Horizontal frame members 9 extend longitudinally of the feed mechanism and support a pair of v-shaped troughs I6, I along which the lengths of tubular stock, indicated at A, are fed. Laterally adjacent each of the troughs I0 there is mounted for reciprocation a longitudinally extending feed bar II, which may be of tubular form and which is'supported on carriages I2 and I3, each mounted for limited travel along its guide rail I4 and fitted with rollers I engaging the upper and lower edges of said rail, as seen in Figure 7. Each feed bar II is provided at intervals with fingers I6 hingedly attached to the bar at IT, so that the free ends of the fingers I6 may rest upon the lengths of stock A in the troughs ID or may swing down into the troughs in the absence of such stock therein. When a length of stock A is placed in the trough or guide III the fingers I6 which stand laterally adjacent the length of stock will rest upon it, as seen on the left-hand side of Figure 3. But one of the fingers, as indicated at IIi at the right side of Figure 3, immediately adjacent the end of the stock element A, will swing down so as to engage said end of the stock for driving it forward along the trough or guide I9 when the feed bar II, which carries the fingers I6, is reciprocated toward the screw machine.

- The feed bar II is operated through a link I8 connecting the bracket 13 to the upper end of a lever I9 fulcrumed at 29 on a bracket 2| extending from the support 6 adjacent the screw machine. The lever I9 is rocked through a limited are by a pitman 22 actuated by means built into the screw machine, and this serves to drive the lever I9 and its connected feed bar I I in a direction away from the screw machine, in other words, through an idle stroke of its reciprocation. In moving in this direction the lever I9 actuates a rod 23, carrying a collar 24 by which a spring 25, coiled around the rod 23, is compressed against a stop 26 fixed 0n the frame 9, so that upon return movement of the pitman 22 the energy stored in the spring 25 serves to drive the lever I9, link [8 and feed bar I I in the opposite direction to effect its working stroke by which the stock A in the trough I9 is advanced by movement transmitted to the end of the member A through the finger I6". Upon the next idle stroke of the feed bar I I the finger I6 will be drawn back from the end of the stock A, and if the stock has been advanced suiiiciently by the preceding working stroke, then the next finger of the series will drop down behind the end of the stock A so as to engage it in driving relation during the following working stroke of the feed bar II. If the stock has not been advanced this far, then the same finger will re-engage it in the next working stroke for further advance movement. In this way the feed bar advances the stock A inter.- mittently to supply the lengths of material need- .ed for successive units of the product, in this case, a pipe nipple which is made from the stock A by the screw machine.

Since the working stroke by which the stock A is advanced is effected through the agency of the spring 25, the effective stroke may be varied through a considerable range, corresponding to the various lengths of nipples which the screw machine may produce, and such variation may be accomplished by merely arresting the advance movement of the stock at a point at which a sufficient length of it has been projected through the collet of the machine spindle I. The stock is thus arrested by the stock stop 5 standing normally at the desired distance away from the ends of the spindles I; then, as already mentioned, the stock stop 5 advances toward the spindles I to push back the stock by a certain distance before it is finally gripped by the spindlesI and operated upon by the cutting tools.

The driving pitman 22, by which the lever I9.

and feed bar II are actuated for the idle stroke, is connected to the lever I9 by a pin 21 engaging a slot 28 in the pitman, and this slot 28 may be long enough to allow for any discrepancy of stroke or timing as between the feed bar II and the pitman 22.

When one of the lengths of stock A has been advanced along its trough or guide I0, until the end of said stock element is engaged by the last feeding finger I6 which is the one nearest the screw machine, it becomes necessary to supply a fresh length of stock to the trough II] to follow up the piece which has thus been nearly used up in the machine. This is accomplished automatically. Additional lengths of stock are indicated at B (see Figure 3) supported on inclined surfaces 29 which form a stock rack for this reserve supply of material.

In its feeding stroke the finger I I5 engages the beveled cam face 30 of an arm 3| extending from a rock shaft 32 which is mounted parallel to the terminal portion of the guide or trough I0 adjacent the screw machine. The travel of the finger H in its lowered position, engaging the end of the stock A, thus rocks the lever 3| upwardly and turns its shaft 32 through a few degrees so as to rock a second lever arm 33 (see Figure 5) downwardly in opposition to aspring 34 for withdrawing a roller 35 from the annular groove or channel 36 of a clutch collar 31. In its normal position the roller 35 engages a cam surface 38 (see Figure 6) at one side of the groove 35 and holds the clutch element 3'! out of engagement with a cooperating clutch member 39 in oppositio to a spring 40. But when the roller 35 is swung out of the groove 35 the spring 40 shifts the collar 31 into clutching engagement with the member 39 which is carried on the end of a constantly rotating shaft 4|. The clutch collar 31 is splined to the shaft 42 co-axial with the shaft 4| so that upon engagement of the clutch members 31 and 39 the shaft 42 is rotated. Its movement is limited to a single revolution because the actuation of the lever arms 3| and 33 by the feeding movement of the finger |5 is only momentary, and the spring 34 therefore returns the roller 35 to the groove 36, so that it again engages the cam surface 38 as the latter turns into registration with the roller 35, causing the collar 31 to be shifted out of driving connection.

This single revolution of the shaft 42 serves to release one of the reserve lengths B of stock from the inclined rack 29. At intervals in the length of this rack there are upwardly projecting retaining dogs 43 extending through slots at the outer edges of the rack 29, laterally adjacent the troughs or guides l0. Each of the dogs 43 is carried on the end of a rocker arm 44 which engages an eccentric 45 on the shaft 42. Corresponding hold-back dogs 46, disposed normally below the supporting surface of the rack 29, are positioned to be projected upwardly between the length of stock B which rests against the dogs 43 and the next piece of stock above it on the rack. Each of the dogs 45 is carried on a rocker 41 engaging an eccentric 48 on the shaft 42. Thus the single revolution of shaft 42 causes one set of dogs 43 to be withdrawn downwardly, releasing a length of stock B and allowing it to roll into the trough l0. At the same time, the dogs 46, being projected upwardly, will hold back the remaining lengths of stock on the rack until, as the revolution of the shaft 42 is completed, the dogs 43 are projected upwardly again to their original positions, and the hold-back dogs 46 are withdrawn downwardly, permitting all the remaining stock to shift downward along the inclined surface of the rack 29 into contact with the stops 43. Since the shaft 42 extends substantially throughout the length of the stock rack and feeding mechanism, the reserve pieces of stock B, of whatever length they may be, are thus fully controlled and accurately released to the trough H1 when needed for use in the machine.

In order that the feeding fingers It shall not interfere with the delivery of the length of stock from the inclined rack 29 to the trough or guide l0, these fingers are all simultaneously raised by a limited rocking movement of the feed bar II which occurs periodically during each idle or return stroke of the reciprocating bar Each of the continuously rotating shafts 4| carries an eccentric 5| which actuates a link 58 connected to rocker arms 52 depending rigidly from the bar H. The connection is in the form of an elongated pivot rod 53 extending between the arms 52 which are spaced apart by more than the amount of the maximum stroke of the bar so that as the bar reciprocates the rod 53 may slide through the end of the link 51? While maintaining the connection between the bar II and the eccentric 5|. Figure 4 indicates in dotted outline the extent to which the fingers it are lifted away from the guide trough H! by the action of the eccentrics 5|.

Each of the fingers i6 is carried on a cylindrical pivot I'i formed on the end of a short block 60 which is secured to a flattened area 6| of the feed bar As shown in Figure 4, the bar H is of tubular form and is slotted at 82 to accommodate the edge of the finger l5 adjacent its pivot IT. The slot 62 is made deep enough to allow some play of the finger I6 about its pivot I! so that it may either ride on top of the length of stock A in the guide trough ID or may drop past the end of the stock element for driving engagement therewith as the stock is advanced along the guideway (see IG in Figure 3). But when the feed bar I is rotated by action of the eccentric 5|, the bottom of the slot at 63 picks up the finger l6 and swings it outwardly to the limiting position shown in dotted lines in Figure 4.

It will be understood that all movements of the screw machine itself and of the feed mechanism are derived from a single driving motor shown at 55 in Figures 1 and 2. This motor is connected by suitable gearing with a horizontal shaft 86 which extends into both of the heads 2 and 4 and serves to operate the spindles and other timed mechanism therein. At the end of the machine adjacent the stock-feeding mechanism the shaft 56 carries a so-called barrel cam 61 which includes a groove 58 engaged by a follower roller 69 on the rocker arm 18. This arm extends from a shaft H which carries a second arm 12 to which the pitman 22 is connected. Thus the contour of the groove 68 controls the motion of the pitman 22 which, in turn, is transmitted to the lever IQ for effecting the return stroke of the feed bar I I, as already described.

The bracket 6, which supports the forward end of the stock rack and feed mechanism, is preferably hollow and serves to enclose driving gearing for the shafts 4|. This includes a drive sprocket I3 from which a chain '14 extends around driven sprocket wheels 15, I5 which are mounted respectively on the ends of the two shafts 4|, so that the latter are rotated continuously during operation of the machine.

The reciprocation of the stock stop 5 for pushing back the stock to working position after it has been overfed, as already described, is controlled by a cam drum 16 on the shaft 56, as shown in Figures 8 and 9. This drum includes a barrel cam groove 71 engaged by a roller I8 on the end of a lever 79 which is fulcrumed at 88 in brackets 8| extending from the inner face of a vertical wall of the head 4. The upper end of the lever 79 is in the form of a shifter fork 82 engaging a grooved collar 83 on the shank 84 of the stock stop 5, so that as the cam drum 16 rotates the lever 19 reciprocates the stop 5. As seen in Figure 9, the stop includes a pair of oppositely extending arms 5*, 5 and its shank 84 is rotatively journaled on a shaft 85 extending through the vertical wall of the head 4. When the arms 5 5 extend horizontally, they are disposed-opposite the axes of the spindles I, for encountering the stock as it is fed through the spindlesl After the stock has thus encountered the stop arms and then has been forced back to its final position by reciprocation of the stop 5, the arms 5, 5 are swung to oblique positions indicated in dotted outline at 5', 5 on Figure 9, so as to permit the tools to work upon the portions of the-stock projecting from spindles I, I. This rotative adjustment'of the. stock stop 5 is effected by means of aface cam shown as a groove 86 on one end of the drum I6, engaged by a roller 81 on the arm 88 of a bell crank lever fulcrumed at 89, with its longer arm 99 connected to a link 9| extending vertically inside the head 4. The upper end of the link 9I is attached to the short arm 92 of a flange 93 rigidly secured to the shank B4 of the stock stop 5. Thus, as the cam groove 86 is rotated, the bell crank lever is swung through a limited angle, moving its longer arm 90 downward to the position shown in dotted outline in Figure 9, and this movement is transmitted through the link 9| to swing the stop arms to positions 5 5. Continued rotation of the cam drum I6 causes reverse rotation of the stop 5 back to its initial position ready for encounter with the next lengths of stock to be projected through the spindles I, I.

For varying the length of the unit work-piece which is to be produced by the machine, as, for example, a pipe nipple, it is only necessary to alter the initial position of the stock stop 5 at which it first encounters the stock fed through the spindles I, I. This may be accomplished by having the head 4 of the machine longitudinally adjustable on the bed or base I and providing any suitable meansfor effecting such adjustment. Incidentally, this arrangement adjusts the spindles 3, 3 and the tools carried by the head 4 simultaneously with the adjustment of the stop 5, so that the tools which work upon the stock, and the spindles 3, 3 to which it is transferred in the process of manufacture, maintain the same relation to the stock at all times, and regardless of the total length of the piece upon which the work is performed.

By means of this simple adjustment the machine may be adapted to manufacture a considerable range of lengths of pipe nipples or other work-pieces. Since the feeding stroke by which the stock is advanced is effected by expansion of the spring 25, the full range of this stroke need not be utilized at any time, and only so much of it will be employed as corresponds to the length of the unit work-pieces for which the machine is adjusted, the slot 28 in the pitman 22 allowing the pitman to complete its cycle independently of the point at which the stock is arrested by the stop 5. The maximum feeding stroke will be substantially greater than the maximum length of work unit which the machine is designed to produce, thus insuring that each working stroke of the feed mechanism shall be capable of advancing the stock by a distance corresponding to the length of the work unit in production, plus the three-quarter inch over-feed above described.

Some of the operations performed by the machine on the stock will involve rotation of the stock carried by the spindles I, I, and this includes the entire length of the pieces A extending back into the troughs or guideways I0, I9. The weight of these lengths of stock might furnish enough frictional hold on the troughs I9, I0 so that this rotation would cause the elements A to roll up'the sides of the troughs and out of control; accordingly, some, or all, of the feeding fingers I 6 may be equipped with projecting studs I6 as seen in Figure 12, so that as each finger moves into engagement with the end of the stock A its stud IIi will enter the bore of the pipe in which it fits loosely and will thus tend to restrain the end of the pipe within safe limits as it is rotated during operation of the machine. It will be readily apparent that for use with stock in the form of solid rods or bars instead of tubing, the elements I6 will be of modified form, in the nature of caps or flanges, which will interlap externally instead 'of internally with the end portion of each length of stock.

The machine is, of course, adapted to handle a considerable range of diameters of stock, as well as to produce work-pieces of different lengths, and-since the stock must be supported axially so as to be fed accurately into the hollow spindles I, I, a change in the diameter of the stock should be accompanied by a shifting in the position of the troughs or guideways II]. This is provided for by mounting these V-shaped troughs ID on vertically disposed supports 95, as seen in Figures 1 and 11, positioned at intervals in the length of the frame 9 and vertically adjustable thereon. The lower edge of each part i an oblique cam surface resting upon a correspondingly inclined cam member 96, and the cams 96 are all connected by a longitudinally extending rod or bar 91. The end of the bar carries an adjusting screw 98 which impinges against the extreme end of the frame 9 for shifting the bar 91 and the cams 96 longitudinally so as to raise or lower the supports 95 and the trough I9 which they carry. Suitable clamping screws 99 may be provided to hold the parts 95 at adjusted position, and, if desired, one of the plates may carry scale markings cooperating with an index mark I00, as seen in Figure 11, so that exact positions of adjustment may be thus indicated for different sizes of stock.

I claim as my invention:

1. A stock feeding mechanism including an upwardly open guideway for a length of stock, a feed bar mounted for reciprocation parallel to said guideway, a plurality of pivoted fingers extending laterally at intervals from said bar adjacent said guideway and urged yieldingly toward it by gravity, whereby some of said fingers initially rest against the surface of a length of stock and then fall successively past the end of said length into position for driving engagement therewith as the stock is advanced along the guideway, and means for reciprocating the bar.

2. A stock feeding mechanism including a guideway for a length of stock, a feed bar mounted for reciprocation parallel to said guideway, a plurality of fingers extending laterally at intervals from said bar adjacent said guideway and urged yieldingly toward it, whereby some of said fingers initially contact the side of a length of stock and then swing successively past the end of said length into position for driving engagement therewith as the stock is advanced along the guideway, yielding means connected for moving the bar yieldably in feeding direction, and a stop positioned to positively engage the opposite end of the stock.

3. A stock feeding mechanism including a guide for a length of stock, a feed bar mounted for reciprocation parallel to said guide, a plural ity of fingers extending laterally at intervals from said bar adjacent said guide and urged yieldingly toward it, whereby some of said fingers initially contact the side of a length of stock and then swing successively past the end of said length into position for driving engagement therewith as the stock is advanced along the guideway, yielding means connected for moving the bar in feeding direction, and a stop engageable with the opposite end of the stock and adjustable to limit the travel of the stock to something less than the maximum stroke of the bar.

4. A stock feeding mechanism including a guide for a length of stock, a feed bar mounted for reciprocation parallel to said guide, a plurality of fingers extending laterally at intervals from said bar adjacent said guide and urged yieldingly toward it, whereby some of said fingers initially contact the side of a length of stock and then swing successively past the end of said length into position for driving engagement therewith as the stock is advanced along the guideway, yielding means connected for moving the bar in feedin direction, a stop engageable with the opposite end of the stock, and means reciprocating the stop in timed relation to the bar to move the stock in revers direction for a predetermined distance.

5. A stock feeding mechanism including supporting means for a length of stock, intermittently operating feeding means engageable with the stock for advancing it along the supporting means, a stop against which the end of the stock is fed by said feeding means, and means reciprocating said stop after completion of th advance movement of the stock to move the stock in reverse direction for a predetermined distance not less than the length of stock required to be engaged by the supporting means for adequate support of the stock.

6. A stock feeding mechanism including gripping means which intermittently engages a length of stock, yielding feeding means engageable with the stock and operable in a direction to advance it through the gripping means, a stop against which the end of the stock is fed by said feeding means, and means reciprocating said stop after completion of the advance movement of the stock to move the stock in reverse direction for a predetermined distance not less than the length of stock required to be engaged by the gripping means.

'7. In combination with an automatic machine havin a hollow spindle, a feeding mechanism for advancing stock through said spindle, a collet in the spindle for gripping the stock intermittently, and a stock stop disposed opposite the end of said hollow spindle in the machine for limiting the feeding movement by engaging the end of a length of stock fed through the spindle, together with means in the machine connected to move said stop periodically after completion of the advance movement of the stock toward the spindle in contact with said end of the stock and through a measured distance not less than the minimum length of stock required to be gripped by the collet of the spindle.

8. A stock feeding mechanism including a guide for a length of stock, a feed bar mounted for reciprocation parallel to said guide, a plurality of fingers extending laterally at intervals from said bar adjacent said guide and urged yieldingly toward it, whereby some of said fingers initially contact the side of a length of stock and then swing successively past the end of said length into position for driving engagement therewith for advancin the stock along the guideway with each reciprocation of the bar, a support for a reserve length of stock laterally adjacent said guide and inclined toward it, holding means associated with the support for retaining the stock thereon, and a, member extending in the path of 5 active feeding movement of the last finger on the feed bar, said member being connected to release said holding means during the final feeding movement of the stock along the guide by said last finger of the bar to allow the reserve length of ill stock to be shifted by gravity onto the guide.

9. A stock feeding mechanism includin an upwardly open guide channel for a length of stock,

a feed bar mounted for reciprocation parallel to said channel, a plurality of fingers each pivotally attached to said bar and extending laterally at intervals in position to rest upon a length of stock in the channel and to drop successively past the end of said length into position for driving engagement therewith when the stock is advanced along the channel, a support for a reserve length of stock laterally adjacent said channel and inclined toward it, means for automatically releasing such reserve length of stock from said inclined support when the rear end of the stock in the channel passes the forward end of the reserve length on the support, and means for moving the feed bar in timed relation to such release and in a direction to lift its fingers clear of the channel to admit th reserve stock thereto.

10. A stock feeding mechanism including an upwardly open guide channel for a length oi." stock, a feed bar mounted for reciprocation parallel to said channel, a plurality of fingers each pivotally attached to said bar and extending laterally at intervals in position to rest upon a length of stock in the channel and to drop successively past the end of said length into position for driving engagement therewith when the stock is advanced along the channel, a support for a reserve length of stock laterally adjacent said channel and inclined toward it, means for automatically releasing such reserve length of stock from said inclined support when the rear end of the stock in the channel passes the forward end of the reserve length on the rack, means for reciprocating the feed bar, means for supporting said bar for rotation about an axis parallel to its direction of reciprocation, a continuously rotating eccentric, a radius arm fixed to the feed bar and a link connecting said arm with said eccentric for periodically rocking the feed bar to lift its fingers above the channel providing clearance for the admission of reserve stock thereto, said eccentric being geared in timed relation to the reciprocating means for thus rocking the feed bar and lifting the fingers during the idle stroke of the bar.

11. A stock feeding mechanism including a supporting guideway for a length of stock, a. feed bar mounted for reciprocation alongside the guideway, reciprocating drive means, a yielding member reacting between a fixed abutment and said feed bar with a connection to said drive means whereby the yielding member is alternate- 1y stressed by the drive means and released for causing a feeding stroke of the bar, said bar having a plurality of fingers extending laterally at regular intervals for successive engagement with the end of the stock to advance it along the guideway by intermittent feeding strokes, the interval between successive fingers of the bar being less than the stroke of the reciprocating drive means, and a fixed stop engageable with the advancing end of the stock and limiting its advance at each stroke.

12. A stock feeding mechanism including a supporting guideway for a length of stock, a feed bar mounted for reciprocation alongside the guideway, reciprocating drive means, a yielding member reacting :between a fixed abutment and said feed bar with a connection to said drive means whereby the yielding member is alternately stressed by the drive means and released for causing a feeding stroke of the bar, means on the feed bar engageable with the stock during each feeding stroke for advancing the stock intermittently along the guideway, and a fixed stop engageable with the advancing end of the stock and limiting its advance at each feeding stroke to less than the stroke of the reciprocating drive means.

13. In combination with an automatic machine having a rotatable hollow spindle with means for gripping the stock to rotate it, a feeding mechanism for advancing stock through said spindle including an upwardly open guide channel for a length of stock, a feed bar mounted for reciprocation parallel to said guide with a finger extending laterally from said feed bar to engage the end of a length of stock for advancing it along the guide, said finger having a portion formed for loose interlapping engagement with the end portion of the stock to steady the stock when it is rotated by the spindle.

14. In combination with an automatic machine having a hollow spindle and means in the spindle for gripping the stock to rotate it, a feeding mechanism for advancing tubular stock through the spindle including an upwardly open guide channel for a length of said tubular stock, reciprocatory feeding means including a finger extending transversely to engage the end of the tubular stock, and a stud on said finger dimensioned' to enter said end of the stock for interlapping engagement therewith to steady the stock during its rotation by the spindle.

15. In combination with an automatic machine having a hollow spindle, a feeding mechanism for advancing stock through said spindle and including an upwardly open channel constituting a guideway for supporting a length of stock in alignment with the spindle, a plurality of supports for the guideway disposed at intervals in its length, cam means associated with each of said supports for adjusting it vertically, and means interconnecting said cams for simultaneously adjusting them to raise or lower the guideway.

16. In combination with an automatic machine having a hollow spindle and means in the spindle for gripping the stock intermittently, a feeding mechanism for advancing stock through said spindle including a guideway for a length of stock aligned with the spindle, a feed bar mounted for reciprocation parallel to said guideway, a plurality of fingers extending laterally at intervals from said bar adjacent said guideway and urged yieldingly toward it whereby said fingers contact the side of a length of stock and then swing successively across the end of said length for driving the stock along the guideway, yielding means connected for moving the bar in feeding direction, a stop engageable with the opposite end of the stock which extends through the spindle, means-for reciprocating the stop in timed relation to the feed bar for moving the stock in reverse direction for a predetermined distance, and a main shaft in the machine with a cam on said shaft connected to said yielding means for actuating the reciprocating feed bar, and cam means on the shaft connected to reciprocate said stop.

17. A stock feeding mechanism including a supporting guideway for a length of stock, a feed bar -mounted for reciprocation alongside the guideway, a reciprocating driving pitman, a rockable lever, means connecting said pitman to the lever with play in the direction of pitman movement, a link connecting the lever to said feed bar, a guide rod extending from the lever, a fixed abutment remote from the lever through which said guide rod is slidable, a spring coiled about the rod reacting between said abutment and a stop on the rod whereby the spring is alternately compressed and released by reciprocation of the pitman for causing the feeding stroke of the bar, means on the feed bar engageable with the stock during each feeding stroke for advancing the stock intermittently along the guideway, and a fixed stop engageable with the advanced end of the stock and limiting its advance under stress of the spring to less than the stroke of the reciprocating pitman.

18. A stock feeding mechanism including a guide for a length of stock, a feed bar mounted for reciprocation parallel to said guide, a plurality of fingers extending laterally at intervals from said bar adjacent said guide and urged yieldingly toward it, whereby some of said fingers initially contact the side of a length of stock and then shift successively past the end of said length into position for driving engagement therewith for advancing the stock along the guideway with each reciprocation of the bar, a support for a reserve length of stock laterally adjacent said guide, holding means associated withthe support for retaining the stock thereon, and a member extending in the path of active feeding movement of the last finger on the feed bar, said member being connected to actuate said holding means during the final feeding movement of the stock along the guide by said last finger of the bar to release the reserve length of stock for transfer onto the guide.

JUDSON H. MANSFIELD.