US2226598A

US2226598A - Wire stitching machine

Info

Publication number: US2226598A
Application number: US283021A
Authority: US
Inventors: Joseph T Wright
Original assignee: Harris Seybold Potter Co
Current assignee: Harris Corp
Priority date: 1939-07-06
Filing date: 1939-07-06
Publication date: 1940-12-31
Anticipated expiration: 1957-12-31

Description

s Sheets-sheet 1l J. T. WRIGHT 'WIRE STITCHING MACHINE Filed July` 6, 1.939

4&3.

Dec. 3l, 194().

'4g INVENTOR.

Joasw {Me/awr BY ,me @MJ ATTORNEYS Dec. 31 1940. l .1.1: WRIGHT 2,225,598

:WIRE SYllITCHING MAGHINE Flied yJuly f6, 1959 6 Sheetsf-Sheet 2 A ATTORNEYS Dec. 31, 1940. J. T. WRIGHT WIRE STITCHING MACHINE 6 sheets-'sheet 3 Filed July 6, 1939 Dec. 31, 1940. J, T, WRIGHT 2,226,598

WIRL` 4STITCHING MACHINE Filed July 6; 193e e sheetssheet 4 INVENTOR. Jose-Aw Z #Ke/@Hr BY jaw/am@ ATTORNEYS V Dec. 31, 1940., J. T. WRIGHT WIRE STITCHING MACHINE e Sheets-shet e Filed July 6', 1959 Y @agg-CH BY '/m atented Dec. 3l, i940 Y i y oFFicE WIRE STITCHING MACHINE Joseph T. Wright, Cincinnati, Ohio, assignor to Harris-Seybold-Potter Company, Cleveland, Ohio, a corporation of Delaware Application July 6, 1939, Serial No. 283,021 17 claims. (ci. 1 2) This invention relates to improvements in wire Fig. 10 is a. vertical sectional view taken substitching machines, that is to say machines for stantially on the line Illl of Fig.l6. cutting predetermined lengths of wire from a coil, Fig. 11 is a detail elevational view of the lower forming the wire into staples, driving the staples part of the wire feed block with the die block in and clinching them. The machine of the presits uppermost position of travel. 5 ent invention is a machine of this type designed Figs. 12 and 13 are side and bottom views reparticularly for stitching together the parts of spectively of the same, with the die vblock in its cardboard boxes, and in some cases, metal parts. lower position. f

One of the objects of the invention is the pro- Fig. 14 is an edge view of the wire straightenvision of a. machine of this character wherein the ing unit shown in Figs. 11 and 13.

adjustments for staple length are effected quickly Fig. 15 is a large scale vertical sectional view and easily simultaneously with an adjustment taken through the driver` and driver slide, showwhich maintains the cut-oli wire centrally posiing the mandrel swung out of the way of the tioned with respect to the former slide regardless former and driver slides. i5 of the length of the wire. Fig. 16 is a front view of the mandrel block. 15

Another object of the invention is the provision Fig. 1'7 is a side view of the head showing the of a wire feed embodying improved operating mandrel swung backwardly into position to hold mechanisma length of wire in the path of the former, with A further object is the provision of simple and the shoe withdrawn to inoperative position. effective mandrel and wire gripping means ca- Fig. 18 is a similar view showing the mandrel 20 pable of quick and easy adjustment. withdrawn and the shoe advanced, the parts be- Another object is the provision of an improved ing in a position which they assume when the wire cutting means adapted for oblique as Well driving ofthe staple isbeginning. as square cutting of the wire. Fig. 19 is a similar viewshowing the parts at stiii another object of the invention is the prothe end 0f the driving stroke, theV shoe being 25 vision of an improved operating mechanism for Cammed away by the driver. the former vand driver slides. Fig. 20 is a detail perspective view of a felt plug Another object is the provision of an improved used OI lubricating the Wire preparatory to its mounting for the shoe over which the staple is being fed, straightened and cut ofi. Supported While being driven In the drawings I have illustrated at l0 the base 30 Other objects and features of novelty will ap- 0f a Wlfe Stlchlng mja-Chine, upon which may be pear es i proceed with the description of those Supported a post anvll HI that swings into or out embodiments of the invention which, for the pur- 0f, Gileratlve POSltlOn in a manner Well known in poses of the present application, 1 have illusthe art. From the rear end of the base a column tinted in the accompanying drawings, in whieh- I2 extendsupwardly for the support of a for- 35 Fig. l is a side elevational View of a complete Waldly prOJecting arm 13- AvmOtOr Il drives a box stitcher embodying the present invention. Shaft 5 through the lntermediacy 0f pulleys and Fig. '2 is e front view of the head of the rna- V-belts '6 and a Clutch 0f the type which is au- Chne. 'A A tomatically thrown out after the shaft l5 has 40 Fig. 3 is a rear view on a larger scale of the face turned through 360' The Operation of this 40 clutch may be controlled m a more or less conplate of the head With the former slide at the top ventonal manner by a foot pedal n operating of lts Stroke* through a lever I8 and a link I9.

For some purposes a blade anvil rather than a n y t o post anvil is preferred. My machine provides shgfs adfanedrahhfalhree jfalto means for using a post or a blade interchange- 1g* 1S a T0 l 0 abl The st Il ma be removed and the blade Fig. 6 is a front view of the wire feed block with 2g xlsed inea Thse latter is secured,v as by certain parts broken away and others shown in Screws 2 to a bracket 22 which turns with tmg Fig. 4 is a fragmental view showing the operating mechanism for the former and driver section. nions 23 journalled in the side Walls of the column 50 Fig- 7 iS an edge View 0f the Same. l2. A prop v24 is-pivotally connected at 25 to Fig. 8 is a central vertical sectional view of the bracket 22, and has a free outer end which hangs wire reel and its mounting. down as shown when the blade anvil 20 is in in- Fig. 9 is a sectional view taken substantially on operative position. f When the blade anvil is the line 9-9 of Fig. 6. swung upwardly a slight distance beyond horizon- 55 y Forward of the bearing 2i there is pinned to theshaft a plate 28 which servesvas a brace and anchor for two cams 29 and 3@ with a separator plate 3i therebetween. The

plates

29, 30 and 3i are preferably attached to the plate 28 by two screws or bolts, one of which carries a forwardly projecting pivot 32 upon which are oscillatably supported a link 33 and a link 3d.

'I'he former slide .is illustratedat 35. It is guided in rabbets formed in the rear side of a face plate 36 attached to the arm i3, and is held within said rabbets by a small guard lplate 3l near the top of the face plate and two plates 3d at the bottom thereof which serve also as cams for a purpose which will presently appear. The for- A mer slide is caused to travel up and down by means of a cam follower grotatably mounted on the slide and bearing on cam dil, and by means of a second follower d0 carried by former slide post v35a which also supports a bracket di, follower d@ bearing upon the peripheryl of cam 2Q, These cams are so made as to cause the former slide to have a movement downwardly through approximately a quarter of a revolution of shaft l5, to remain at the bottom of its stroke until the shaft has completed somewhat more than half a revolution, and then to return to the top of its stroke during the balance of the cycle.

The former slide is provided with a clearance slot i2 at its upper end, a central vertical groove da in its forward side, a pair of apertures id in which are mounted pivot blocks Q5, an insert cam plate d5, a cam groove di, and suitable mounting holes for rigidly carrying the two former blocks d8 having grooves 48a (Fig. 15). The pivot blocks 45 constitute mounting means for a bifurcated lever di! which carries roller blocks E@ and a pair of rearward extensions 5i adapted to receive the lower ends of double conical compression springs 52, the upper ends of which fit over projections at the ends of bracket di, see Figs. 3, 17 and 19. The lower end of lever i9 is rigidly aixedto a shoe 53, the front curvilinear surface 5d of which isdesigned to support the center and its dat sides the legs of the descending wire staple substantially throughout the driving portion of the stroke. Rollers 55 mounted upon the blocks 5d and running upon the cam plates 3d serve to re. tract the shoe on the up stroke into a non-interfering position.

Slidably mounted in the groove i3 is a driver slide 56 rigidly carryingdriver. Si. This slide has a cam insert 58 and a post 58a by which it is actuated from the pivot pin 32 and link 33 previously mentioned. Its motion is sinusoidal in character, but its peak occurs somewhat after that of the. former slide, that is to say when the former slide starts downward the driver slide at first moves upward a short distance and then later follows the former slide downward.A The motion of the driver slide diiers from that of the former slide however in that it has no dwell at the bottom or top of its stroke. The function of the cam insert 58 is to withdraw the mandrel at the proper time so that it will be in position to receive the wire advanced by the next feeding stroke and incidentally not interfere with the driving opera.- tion.

epesses On the forward side of the face plate, that is the side shownjin Fig. 2, a wire feed block 59 is mounted to have a small horizontal adjustment, and beside the wire feed block a. mandrel block eli is rigidly mounted. The block b9 is provided Von. its rear side with a horizontal tongue Si that ls slidable in a transverse groove Si in the forward side of the face plate. At one end oi-the tongue di there is a vertical slot @3 which receives one edge of a collar @d that is carried by an adjusting rod S5 which has a reduced inner end that is threadably mounted in the face plate. A thumb screw 66 extends through a slot oli in block 59 and is threadably mounted in a hole @El in the face plate. When this screw is tightened down it xes the position of the wire feed block. When an adjustment of the block is to be made the screw S5 is first loosened, after which the rod 55 is turned to move the block horizontally a desired amount, and then the screw tt is again tightened. The setting of the wire feed block may be determined and duplicated when desired byreference to a scale t@ engraved err theface plate cooperating with the edge i@ of feed block 59, the scale indicating directly the thickness of work to bestitched.

The feed of the wire is effected by the movement of the link 3d previously referred to and a second link 'H pivotally connected with link 3d and rigidly connected with a short shaft H2 that is journalled on the face plate. The effective length of link 'ii may be varied to some extent, as indicated in Fig. 3 where the link is shown bifurcated with the bifurcation straddling a fiatted portion of shaft i2. Clamping screws 'i3 hold the link in different positions of adjustment upon this iiatted portion. On the forward side of the face p late shaft 'i2 carries e. crank lli. It will be apparent that as the pivot pin 32 travels in its circular path around the axis of shaft i5 the outer end of the crank i@ is caused to swing upwardly and downwardly. Varying the length of arm 'H by the adjustment just above described affects somewhat the extent of the swinging motion of crank it.

In Fig. 3, crank id is at the beginning of the cycle. As the pivot pin 32 is turned anti-clockwise 180 about the axis of the shaft i5, the path of any point on arm id describes an arc descending approximately 30 tothe position shown in Fig. 4. Continued rotation of shaft i5 then causes arm Tl to travel upward through an arc of about 60 at which point it reverses and returns to its starting position.

Referring now to Figs. 6 and l0, it will be noted lthat crank 'M fits slidably within a groove in a swivel block 'i5 carried by a dovetail slide I6 that is mounted ina dovetail block 'ill which is secured to a rack 'i8 that is vertically movable in grooves in the pads 'i9 and'li. 'I'he swingingmovement of the crank it therefore imparts up and down movement to the rack i8. Dovetail slide F6 is adjustable in block H by means of a shouldered screw 8i' retained and locked by twin plates 82-2 fixed to dovetail block l?, the plates being mutually offset a'slight amount to accomplish the locking action. The length of stroke of the rack 'i8 maytherefore be changed in two ways, rst by the bodily movement of the block 59 through operation of the adjusting rod and second by movement of the swivel block i5 with respect to block il through manipulation of the screw 8 i.

In the lower part of the block 59 there is a stub shaft 83 upon which is journalled the hub of a wheel84, which is prevented from moving axially in one direction by a disk 65 attached` to the end of the shaft, and in the other direction by'a Wall of the block. itself. The wheel 84 has a rim 86, and between the hub and this rim there is an annular pocket di. The wheel hub has a smooth machined outer surface upon which is journalled the inner element 88 of a one-way or ratcheting clutch. This element has an annular extension 80 provided with gear teeth 90 that mesh with the teeth of rack 18. In the clutch element 08 there are a series of pins 9| upon which are pivotally mounted dogs 92 that are adapted when the clutch element 88 is rotated counterclockwise, as viewed in Fig'. 6, to grip the internal wall of rim 86 and impart motion thereto. Soft springs 93 tend to hold the dogs 92 in operative position. 0n the other hand, when the clutch element 88 is rotated` in the clockwise direction the springs 93 yield and the dogs nmerely slide on the surface of the rim. Hence when rack 18 travels upwardly the Wheel 84 is rotated anticlockwise, while downward movement of the rack merely rotates the inner element of the ratcheting clutch and conveys no movement to the rim of the wheel. In 'an annular recess in the periphery of rim 66 there is mounted a hardened ring 94, between which and another similar but smaller ring 95 the wire W is fed. Ring 95 is carried by a small Wheel 96 that is journalled on`a stub shaft 9T which is carried by the short arm of a bell crank lever 98 pivotally mounted at 99 in he front wall of the feed block 59, Wheel 96 is held against axial movement by a. guard disk |00 secured to the 4end of shaft`91.

The

wheels

84 and 98 have intermeshing gearA teeth |0| and |02 respectively, so that all rotation of w-heel 84 is positively imparted to wheel 96.

In order that the

feed wheels

84 and 96 may grip the wire W with the proper tractive force even though different wires of varying thickness may be used, a coil spring |03 is caused to press against a plate |04 in the longer arm of bell crank lever 98. The compression of spring |03 may be regulated by suitable means. As illustrated herein this means consists of an elongated.

inserts a screw-driver in the slot at the outer end of the bolt and turns the latter in one direction or the other. When the machine is being threaded the wire feed rolls may be separated by means of a lever |0i which is pivoted at |08 and provided with a surface |09 for engagement with the plate |04 when the lever |01 is swung downwardly and outwardly. For the convenience of the operator the point where the wheels 04 and 96 grip the wire is exposed to View by a window H0 in the front wall of the block.

The wire reel is carried by a bracket I| which is attached to the head of the machine. This bracket has a smooth opening therethrough in which is carried a spindle 2 threaded at its rear end to receive a nut H3 provided with a knurled ange ||4. This nut has a cylindrical outer surface which extends into a counterbore in the bracket and is held against longitudinal. movement with respect to the bracket by set screw ||5 extending into a groove ||6 inthe external surface of thenut. The spindle ||2 is held from turning in the bracket because of the the desired amount of friction upon the side 'Y `wal1s of the reel. The hub of spider ||9 rests directly upon the spindle, while the hub of spider |20 rests preferably upon a reduced portion of a knob |2| which is adapted to slip onto or off ofthe spindle readily and is provided with a pin |22 which cooperates with a hook-shaped slot |23' in the spindle, whereby the knob may be quickly put in place or removed therefrom when it becomes necessary to change reels. It will be apparent that the degree of friction to be exerted upon the reel is determined by the adjustment of nut ||3 and-that this adjustment is in no way disturbed when one reel is removed and another one of the identical dimensions placed in position.

Wire from the reel is directed downwardly over a flexible guide arm |24 mounted at its lower end in the wire feed block. The wire enters the feed block through a pocket |25 in which is mounted a. felt plug |26, see Fig. 20, having-a slit |21 therein to receive the wire. This plug is impregnated with a. thin oil soA that the wire is covered with a. thin nlm of lubricant, when it enters the block. 'Ihis lubrication of the wire has been found to be quite beneficial, particularly as to reduction in vwear` upon the wire straightening and staple forming tools and the.

wire guides |28 and |29. After passing through the plug l|26 the wire, which may be either round or fiat, enters a tube |28 which guides it into the bight of the

feed wheels

84 and 96. After leaving these wheels it passes through a curved guide |29 which directs it into the wire straightening unit.

The latter unit comprises plate |30 removably attached to the feed block, see Figs. 1-1, 13 and 14. It carries three straightening elements. The

outer ones |3| -are identical substantially U` shaped elements with rounded heads at their lower ends. These elements are guided by pins |32 and are held in adjusted position by headed screws |33. The middle element |34 has an upwardly extending rounded head |35 on its rear side, the element being open from side to side for a distance above this head. A pin |38 assists in guiding element |34 and a thumb screw |31 holds it in adjusted position. The wire in passing beneath the rounded heads of elements |3| and over the head |35 is straightened. 0n previous machines of this class which include a straightening device, only one of the three elements is adjustable. By providing adiustability for all three elements the wire` can be kept centralized in the desired path of travel, whereas with only the middle element adjustable the wire cannot be so centralized for all diameters or sizes of wire which may be used in the machine.

The wire then enters through a. bell mouth opening |39 in the die holder |40 and thencepasses through the cylindrical die |38 which is secured in holder |40 by a set screw. The die holder is slidable vertically within suitable guide surfaces in the wire feed block i8. The upper end of this carrier is riveted to a plate |41 to which is riveted a cross head |42, Fig. 6. 'The under surface of this cross head bears upon the upper end of an adjusting screw |43, in a short crank .|44 that is keyed to a vstub shaft |45, the latter being journailed in face plate 3,6, see Fig. 5. At the rear end of shaft |45 there is an operating arm MS which carries a roller |47 that is alfranged to run upon cam plate 186, previously mentioned. This cam plate is mounted in the former slide. Its high spotencounters the roller Id] when the former slide nearsl its upper position on the up stroke, that is to say near the end o! the cycle. Normally the carrier4 |40 is held in its lowermost position by a coil spring |48 which bears upon the top of -cross head M2. 'Ima spring may be regulated as to pressure by means of a screw M9, shown in Fig. 6. 'I'he die block |38 is made removable'- and interchangeable. It may have an exit end with a surface square to the direction of travel of the wire as in Figs. 6 and 7, or it may have an oblique surface as shown at i5@ in' Fi. 13. A knife blade |5| bears against the exit surface of the die block. Blade |5| is mounted in a removable and replaceable block i52. Interchangeable blade mounting blocks may be used having provision for supporting the knife blade either square with the direction of travel of the'wire or obliquely thereto in order to cooperate with the square or oblique die blocks. The blade mounting block |52 is fixed in the wire feed block 59, and as the die block rises it carries the wire past the cutting edge of the blade |58 and causes the latter to sever the wire. At this time the length of wire which extends beyond the die block is held in the mandrel, as will be presently explained, and its position is nearly in line with the lower end of the knife blade. Hence that part of the wire which is to be severed is only slightly moved by the cutting action. On the other hand in machines where the cutting is done by va moving knife blade the cutting action tends strongly to displace orbend down one end of the severed wire and places considerable strain upon the gripping'means of the mandrel. Wherean oblique cut is made I prefer to use a small angle,

even as low as 10 or 15.

The fixed mandrel block t is suitably recessed on its rear surface to receive the mandrel |511l which is U-shaped in cross section with its open side to the rear. At its upper end the mandrel is hung upon a pin ld which is carried at the lower end of a vertical lever |55 that is supported upon a pivot las. The lower end of the lever and therefore the pin |513' may be adjusted forwardly and backwardlyby suitable means which in this instance takes the form of an ec-4 centric ii on one end of a shaft |58 provided with a screw-driver slot in its outer end which is exposed at the edge of the block, whereby it may be readily turned. A locking screw |59 may be provided to hold shaft |53 in any desired position of adjustment. The adjustment of the mandrel pivot l@ is for the purpose of setting the limit of rearward swing of the mandrel |53 so that thewire being carried thereby is exactly centralized under the vertical grooves 48a in the former blocks before they begin their downward movement.

l A follower roller |60 is mounted between rearwardly extending projections on the mandrel and bears upon the cam'plate 58 carried in the driver slide as previously mentioned. A leaf spring ISI with an elongated button |62 riveted thereto, projecting through ahole in `the front of the block and bearing upon the mandrel, serves to hold the follower |60 against cam plate 58. After lthe driver slide 56 has driven one staple and rises again to its upper normal position follower IS@ rides onto the low spot of the cam' plate and pen' mits the mandrel to swing rearwardly to carry a rearwardly extending part of the lower endof the mandrel 53 regardless of the size or cross sectional shape oi the wire. At the upper end of the gripper bar there is a rearwardly projecting pin itil which is received between bifurcations in the lower arm oi a bell crank lever it@ that is pivotally supported at Edi in the mandrel block. A tension spring i5@ acts to pull downwardly on this arm of the bell crank and to exert downward pressure on the gripper foot. The raising of the gripper bar in order to releasea wire held in the mandrel is accomplished by' a follower i5@ carried in the upper arm of the bell crank: le@ and cooperating with cam groove il in the former slide. This releasing of the wire by the gripper foot takes place shortly before the mandrel begins its forward swing. it will be observed that the actuation of the gripper bar by the operating means just described in no way interferes with the swinging movement of the man-i drel. A transverse pin il@ mounted in the side i of the mandrelvaords a slide bearing for the gripper bar and serves to maintain the latter in place in the U-shaped guide provided in the rear ,of the mandrel.

@perenoel-The operations of wire feeding, gripping, cutting 0E, transferring to a position beneath the former, forming the staple, driving and cllnching areperformed successively within the course of a single yrevolution of the drive shaft i5, starting and stopping at a point coin-` cident to thehighest rise of the former slide. Assuming that in the previous cycle a length of Wire has been fed and cut oi and is held by the mandrel |53 and gripper iii, i565 in the position of the parts illustrated in Figs. 3, 5, 6 and 17, where the mandrel is swung backward into the path of the former blocks, and that the operator -has depressed the foot lever i i to start the revolution of shaft i5, the former slide then starts downward. After it has descended a short distance the farmers contact the wire held by the mandrel and bend down. the ends thereof forming the legs of a staple, the point of actual engagementof the wire being at the lower ends of the grooves dsa. Therefore, :the staple legs lie in these grooves which at this instant continue downward while the staple crown is still being held by the mandrel and gripper. 1GB', |66 then rises to release the Wire, due to the action of cam groove d1 upon follower E69, and shortly thereafter the mandrel swings forwardly out of the way of the formers and driver, due to the action of cam plate 58 upon follower |60. As the mandrel moves forward the shoe 53 begins its forward movement due to the action of cam plates 38 on followers 55. Directly after the staple is formed the driver starts to move downward. Thefstaple is forced down into contact with the curvilinear surface nl of the shoe, and then as the driving operation continues the staple yitself cams back the shoe whilst being supported The gripper part of the staple crown the shoe supports the lower part of the staple crown until practicallythe end of the stitch. When the staple legs have fully pierced the work they impinge on the clincher block whose upper hardened surface is usually so shaped as to turn the staple ends inward. The stitch is completed as the driver reaches its lowermost position, when the staple ends nearly touch each other on the under side of the work, the stitch and work being squeezed somewhat between the driver and clincher block at the very end of the stroke. While this is oc-` curring the feeding of another length of wire is beginning, that is when the cycle has progressed approximately one-third of a revolution, it being understood that at this time the mandrel is swung forward, as indicated in Figs. 18 and 19, and is in line withthe wire emerging from the die block idd which is then in its lowered position. During the latter parft of the driving stroke and during the first part of the upward travel of the former andv driver slides, the feeding of wire continues. At about the time it ends the gripper bar it@ isvpermttted to descend in response to the action of spring itt. Then while the wire is thus gripped the die block |33 rises and theY wire is severed. Some time before the feed oi.' wire was completed the shoe 53 was retracted, and now the mandrel again moves rearwardly with its new length of wire and positions the latter in ,the path of the former ready to be acted upon in the next cycle.

The width of the staple is determined by the spacing of the formers and the width of the supporting shoe and the mandrel. In most cases this width will not be changed when different jobs are to be performed, but if changes are desired they must be accomplished by substituting dierent iormers, drivers, mandrel land shoe. Frequently however changes in the length of the staple legs are desired. These changes may be eifected with my machine by the simple expedient of adjusting the wire feed block 55 horizontally upon the face plate by the means previously described. The proportions of the parts are such that asA the feed block 59 is moved away from the path of travel of the former and driver a given distance, the additional length of wire fed is exactly double that distance. Hence any in. crease in the length of wire fed isdivided equally between the two legs of the staple.

The feed adjustment effected by the manipulation of screw El changes the length of wire fed independently ofthe position of the feed block 59. This adjustment may beused to alter the relative length of the legs of a staple in case one leg longer than the other is desired. Ordinarily however its chief use is as a means of correcting v any inequality in the length of staple legs.

The adjustment of the effective length of link 'H is essentially a means to establish the correct rtravel of the crank 14, which is a prerequisite for the use of uniform spacings of the engraved scale 69.

' These two adjustments taken in combination afford a means of causing the staple to have legs egual in length and of the values for work thicknesses as indicated by the setting of witness line 10 on the scale 69, regardless of depth of stitch, variations in fabrication of parts or dissimilarity in assembly procedure from one machine to another. They furthermore provide effective means of compensation adjustment for normal backlash and wear in service.

lLt is to benoted that the scale graduations 69 are true fractions of an inch, that is not reduced or enlarged from the standard U. S. calibration for rules and scales. This is a valuableaid to the operator who if he wishes may employ a pocket rule to measure the distance between the right hand edge 10 of the feed block and the left hand edge of mandrel block 60 which coincides with the zero mark on scale 59. The measurement of this space between blocks is a true representation of the actual thickness of work to be stitched' for any particular setting.

Having thus described my invention, I claim:

l. In a wire stitcher, a mandrel adapted to receive and hold a. length of wire, said mandrel being mounted to swing about a pivot at its upper end for moving said lengthvof wire into position to be formed into a staple, actuating means arranged to operate -upon the mandrel below its pivot, and means for moving the pivot laterally to change the location of .the arc through which the lower end of the mandrel swings.

- 2. in a wire stitcher, a mandrel adapted to receive and hold a length of wire, said mandrel being mounted to swing about a pivot at its upper end for moving said length of wire into position to be formed into a staple, cam means operatively associated with the `mandrel below said pivot for swinging the'mandrel about the pivot, and

' upper end, actuating means arranged to operate upon the mandrel below its pivot, a gripper mounted to slide up and down in said mandrel, means for moving the pivot to change the location of the arc through which the lower end of the mandrel swings, and means for reciprocating said gripper arranged to function independently of the position of said pivot.

4. In a wire stitcher, a mandrel adapted. to receive and hold a length of wire, said mandrel being mounted to swing about a pivot at its upper end for moving said length of wire into position to be formed into a staple, actuating means arranged to operate upon the mandrel below its pivot, a vertical lever in the lower end of which said pivot is mounted, a fulcrum for said lever above said pivot, and means for turning said lever on' its fulcrum to adjust said pivot and thereby change the location of the arc through which the lower end of the mandrel swings.

5. In a stitching machine, a mandrel, a former slide, former legs thereon adapted to bend down the ends of a length of wire carried by the mandrei, a driver slide mounted to reciprocate between the legs of the former, a shoe movable into and out of the space between said legs for supporting` the staple during thevdriving operation, and a bifurcated support for said shoe pivotally hung in said former slide on opposite sides of the path of said driver slide.

6. In a stitching machine, a mandrel, a former 'slide, former legs thereon adapted to bend down the ends of a length of Wire carried by the mandrel, a driver slide mounted to reciprocate bein said former slide on opposite sides of the path of said driver slide, spring means ior urging said shoe forward .toward operative position, and cam means for withdrawing said shoe as the former slide rises on its up stroke. y

7. In a stitching machine, a mandrel, a former slide, former legs thereon .adapted to bend down the ends of a length of wire carried by the mandrel, a driver slide mounted to reciprocate beg tween the legs of lthe former, a shoe movable into and out of the space betweensaid legs for supporting the staple during the driving operation, a bifurcated support for said shoe pivotally hung in said former slide on opposite sides oi the path of said driver slide, spring means for urging said shoe forward toward operative position, a pair of fixed cams at the sides of the former path, and cam followers carried by the said bifurcated support for engagement with said cams, whereby the shoe is swung out of the way as thelformer slide rises on its up stroke.

8. In a machine of the class described, a tace plate, a Wire feed block adjustableon said face plate, staple forming and driving means in said face plate, an oscillatable crank mounted in said face plate and operatively associated with said forming and driving means, and wire feeding means in said wire feed biock having a slide con= nection with said crank, whereby the edective radius oi the crank is varied as the wire feed block is adjusted in a straight line toward or away from the center of oscillation o' said crank, thereby producing a variable feed of the wire.

9. In a machine oi the class described, a face plate, a wire feed block adjustable on said face plate, staple forming and driving means insaid face plate, an oscillatable crank mounted in said face plate and operatively associated with said` forming and driving means, Iand wire feeding means in said wire feed block having a slide conf nection with said crank, whereby .the eective radius of the crank is varied as the wire feed block is adjusted in a straight line toward or awa-y from the center of oscillation of said crank, thereby producing a variable feed of the wire.

10. In 'a machine of the class described, a face associated with said staple forming and driving mechanism for oscillating said crank, Wire feed ing means in said wire feed block having a sliding connection with said crank whereby the effective radius of the crank is varied as the wire feed block is adjusted bodily toward or away from the path of travel of said staple forming means, andA whereby the position of cut with respect to the center line of the staple driving means is changed in proportion to the length of wire fed and cut oi.

11. In a machine of the class described, a face plate, a wire feed block adjustable on said face plate, staple forming'and driving means in said face plate, an oscillatable crank mounted in said face plate, means associated with said staple forming and driving mechanism for oscillating said crank, wire feeding means in said wire feed block having drive shaft and connected at its free end with a second link, the opposite end of the second linklbeing xed to said crank at its ams of oscillation, and adjustable means for varying the length of said second link and the angle through which said crank oscillates.

13. In a machine oi the class described, a face plate, a wire feed block adjustable on said face plate, staple forming and driving means in said face plate, an oscillatable crank mountedr in said face plate, wire feeding means in said wire feed block havinga slide connection with said crank, whereby the eective radius of the crank is varied as the wire feed block is adjusted toward or away from the center of oscillation of said crank, thereby producing avariable feed oi the wire, and gauge marks on the face plate when in register with e. witness on said wire feed block to show the thickness of work accommodated for a4 given adjustment of the feed block 14. 1n a machine of the class described, a face plate, a wire feed block bodily adjustable on said face plate, staple forming and driving means in said face plate, an oscillatable crank mounted in said face plate, wire feeding `means in said wire feed block having a slide connection with said crank, whereby the effective radius of the crank is varied as the wire feed block is adjusted toward or away from the center of oscillation of said crank, thereby producinga variable feed of the wire, and gauge marks on the face plate when in register with a witness on said wire feed block to show the thickness of work accommodated for a given adjustment of the feed block, the parts being so proportioned and designed that the movement of the feed block equals the change in thickness of the work.

15. In a machine of the class described, a wire feed comprising a reciprocable rack, feed rolls, a

pinion meshing ,with said rack, means operatively associated with .saidpinion for ratcheting plate, a wire feed block bodily adjustable on said face plate, staple forming and driving meansver-j,y tically reciprocable in said face plate, an oscil' latable crankmounted in said face plate, means" said rolls forward in a wire'feeding Vdirection only r eating movements ofi'thefrack, and means for reciprocating the. rack-comprising a guide ounted upon the rack tiaris'versely thereof, a y'slide in said guide, aswivel mounted in said slide, oscillating crank lhaving `a -slidable connection. with-said swiveLand fmeans for adjusting said slidev to different positions within saidV guide for regulating the length lof throwoi' said rack.

16.. Ina machinejofthe class described, a wire jvfedtcomprising arryoscillating crank, a drive shaft rotatable orice-iforl each cycle of the mavIchine,'a link eccentricallyfconnected with said drive shaft and connectedatlits'free end with a second link,'thel opposite' end of the second link being fixed to said crank at its axis of oscillation, and adjustable means vfor varying the length of said second link andthe angle through which said crank oscillates, a. reciprocable rack, a pinion meshing with said rack, means operatively associated with said pinion for ratcheting said rolls spaanse l '7 forward in a wire feeding direction only as the slide, former legs thereon adapted to bend down pinion oscillates in response to the reciprocating the ends of a length ot wire carried by the manmovement of the rack, and means for reciprocatdrel. a driver head and driver slide mounted to ing the rack from said oscillating crank comprisreciprocate between the legs of the former, a

5 ing a guide mounted upon the rack transversely shoe movable into and out of the space between 5 thereof, a slide in said guide, a swivel mounted in f said legs for supporting the staple during the said slide having a sliding connection with said driving operation, and a biiurcated support for oscillating crank, and means for adjusting said said shoe pivotally hung in said former slide and slide to different positions within said guide for approximately in the line of the path of said lo regulating the length or throw ot said rack. driver head.

17. In a stitching machine, a mandrel, a former JOSEPH T. WRIGHT.