US2317308A - Tie stitch mechanism - Google Patents

Description

April 1943- w. R. SPILLER 2,317,308

TIE STITCH MECHANISM Filed March 21, 1941 3 Sheets-Sheet 1 L L ,25/ v 5 49 m zaj ZZQ w zaa w w I INV ENT OR.

ATTORNEY 5 April 20, 1943. w. R. SPILLER 2,317,303

TIE STITCH MECHANISM Filed March 21, 1941 3 Sheets-Sheet 2 F765: 5 F76- 6' F/G'. 7

' INVENTOR.

A TTORNEYF5 April 20, 1943. w. R. SPILLER TIE STITCH MECHANISM INVENTOR. kW/zmnfif /zut m My; 1%

ATTORNE Patented Apr. 20, 1943 UNITED STATES PATENT OFFICE 33 Claims.

This invention relates to improvements in tie stitch mechanisms, that is to say mechanisms for effecting relatively close spacing of stitches at the ends of a seam, especially a side seam of a box blank. The invention is in the nature of an improvement upon my Patent No. 2,266,550 issued December 2, 1941.

One of the objects of the present invention is the provision of tie stitch mechanism which shall be automatically operable, partly under the control of the work itself, for producing tie stitches at the ends of a box side seam.

Another object is the provision of means of the character described wherein the automatic control is effected by electrical means.

Another object is the provision of means of this character which shall be effective without machine adjustsments for tie stitching seams of different lengths.

Another object is the provision of controls for the electrical apparatus which will function to render the tie stitching mechanism operative or inoperative, or to change from full spaces to short spaces throughout the length of the seam.

Other objects and features of novelty will appear as I proceed with the description of that em bodiment of the invention which, for the purposes of the present application, I have illustrated in the accompanying drawings, in which Fig. 1 is a diagrammatic perspective view of control mechanism which may be employed in carrying out the invention, the figure also including an electric wiring diagram.

Fig. 2 is a fragmental View corresponding to Fig. l but showing some of the parts in a diiferent position.

Fig. 3 is a detail elevational view of parts of a ratcheting mechanism used in connection with the invention.

4 is a perspective view of certain parts of the machine having to do with the feeding in and delivery of the work blanks, the view looking in a direction opposite to that of Fig. 1.

Fig. 5 is a fragmental View of a box side seam having tie stitches at the ends of the seam.

Fig. 6 is a similar View without tie stitches in the seam.

Fig. 7 is a similar view showing a seam with closely spaced stitches effected by using the tie stitch mechanism throughout the length of the seam.

Figs. 8 to 12 inclusive are detail views showing various positions of the ratcheting mechanism when the machine is set to effect tie stitching and produce a seam like that of Fig. 5.

Figs. 13 to 17 inclusive are similar views of the ratcheting mechanism. where the machine is set to produce a seam like that of Fig. 6.

In the drawings the stitcher head of a wire stapling or stitching machine is indicated at IS, the stitching mechanism within the head being driven by a shaft [1 conventionally in such manner as to form and drive a stitch for each revolution of that shaft.

A gear, pulley, or other power transmitting means I 9 is free to revolve upon shaft l1 and may take driving force from an electric motor or the like, not shown. The shaft I! may be locked to the driving element I9 by a clutch 23 of conventional type. A throw-out rod 2!, when raised, disengages the clutch, and when this rod is lowered the clutch elements engage by spring pressure, as is common in the art.

The machine is adapted to feed a box blank forward step by step between stitches through a ratcheting action. A crank 9a pinned to shaft l7 serves to reciprocate a connecting rod 29 which is pivoted to a block 30 that is adjustably fixed upon an arm 28 having a hub 28a loosely mounted upon a shaft 26. This shaft carries a one-way ball clutch 21 that is adapted when turned in one direction to drive a ring gear 25 which meshes with a gear 24 on a shaft 23 which carries a feed roller 22 mounted just below the table of the machine and projecting slightly through an opening in the table so that the under surface of the work blank maybe engaged by the roller.

This ratcheting mechanism also comprises a disk or crank 200 fixed to shaft 26 and having a projection 21H to which is attached the lower end of a spring 202 which when under tension tends to rotate the disk 200 in a clockwise direction as viewed in Fig. 1. A pin 203 projects laterally from disk 20!] in a position to be engaged by arm 28. When that arm is moved upwardly by the connecting rod 29 from the position illustrated in Fig. 1 it revolves the disk 20!) and the shaft 26 counterclockwise and places the spring 202 under ad ditional tension. When arm 28 moves downwardly spring 202 rotates the disk and the shaft clockwise. counterclockwise movement of shaft 26 turns the ball clutch without effect upon the gear 25, but movement in the clockwise direction is transmitted through the connections shown to feed roller 22. When the clockwise movement under the action of spring 202 is not interfered with the feed movement of roller 22 are uniform in extent. I provide means however for interrupting certain of these feeding movements when.

they have progressed through a portion only of the work forwarding stroke, and this means in the illustrated embodiment, consists of a lug 2M adjustably mounted on disk 296 by means of a slot and bolt connection 265, together with a stop pin 2% which may be dropped into position to engage lug 25 1 or may be raised above that position-by means of a solenoid 261. It will be obvious that when the pin 226 is down the clockwise movement of disk 286 will be interfered with or interrupted before the normal stroke is finished, and consequently there will be; a short movement of roller 22, thereby advancing the work a distance less than at times when the'pin 206 is in raised position.

A cam shaft 60 is arranged to be driven at about an oscillatable shaft 52 upon which is fixed a bracket 5| that carrie a forward drop roll 49 one-third the speed of shaft IT by means of gears.

6|, 62 and 63 and a clutch 6d, gear 6! being rotatable upon shaft 60 except when locked thereto, by

clutch 64. Clutch 64 is of the same general character as clutch 28, and is adapted to be disengaged by a throw-out rod 65 when the latter is depressed. Shaft 60 carries four cams fii fil, 68 and 69 for purposes corresponding approximately with the purposes of similar cams in my copending application Serial No. 352,001, previously mentioned, to which reference may be had for a more detailed disclosure.

Cam 66 operates through a follower 95 to depress a slidable post 95 against the action of a spring 95a which is connected at one end with a variable fulcrum lever 89 that is pivotally connected at 89a with post 95 and at 891) with throwout rod 2 I. A spring 2Ia exerts a downward pull on'rod 2i. When the parts are in the positions illustrated in Fig. 1 the. fulcrum of this lever is at the point of support between a lateral extension 81 on the lever and the high point of a cam 86 on an oscillatable shaft 85. This shaft is biased to the position shown by a crank I I 2 and a spring Il2a, its movement in that direction being limited by a stop II2b. Shaft 85 is mounted in fixed bearings, not shown, and is connected by a universal joint 83 with a shaftfi'I which is movable in a vertical direction through a small angle. Near its outer end this shaft has bearing in a slidable vertical post IE2 on the upper end of which there is a follower II!!! which runs upon the cam 61. A coil spring III tends to lift the post I02 and to hold the follower Hi0 against its cam. The bearing in the lower end of the post is such as to provide the necessary play to accommodate the change in angularity between the post and the full and dotted line positions of the shaft 8I.

On the outer extremity of shaft llI there is a trigger 16 which is pinned or otherwise secured to the shaft. In the raised or full line position of the shaft this trigger extends up into the path of the work. When the operator inserts abox blank into the machine he presses it against this trigger, thereby rotating the shaft 8 I and through it the shaft 85 to an extent sufficie nt to shift the high spot of cam 86 out from'under the projection 81, thereby permitting spring 2Ia to swing lever 89 about the pivot 88a asa fulcrum and to withdraw the throw-out rod 2!, thereby permitting the elements of clutch 26 to engage.

Referring now to Fig. 4, as previously explained, 22 is a feed-in roller which is driven intermittently through a given are to forward the work step by step between successive stitching operations. 3| is a similarly formed roller positioned at the rear of the machine at a suitable distance from roller 22, and preferably adjustabove roller 22 and a rear drop roll 52 adjustable backward and forward upon the bracket in order to locate the drop roll above the roller 3i in all positions of adjustment of the latter. When the shaft 52 is swung counterclockwise, as viewed in Fig. 4, the work is gripped between the roller 22 and the drop roll 49, whereas when the shaft is swung clockwise the work is gripped between the roller 31 and drop roll 52.

Cam 68 controls the position of shaft 52 and thereby of the drop rolls. A foliower H3 runs upon this cam, and through a crank H4 oscil lates a short shaft II5 to which is attached a depending crank II6, the latter being connected by a rod H9 with a crank I2! which depends from and is secured to shaft 52. When the fol lower H3 is on the high spot of the cam, shaft 52 is swung clockwise to force drop roll 56 down against roller 3I. A tension spring Iii acts to hold the follower against the cam and to swing shaft 52 counterclockwise when the cam permits.

Control of the throw-out rod andof the stop pin 266 is preferably'effected by electrical means which I will now describe. 55 is a metal plate as sociated with either the table of the machine or the stitcher head, and 52 is a spring metal finger which makes contact with plate 55 except when a work blank i passing between them. A conductor 288 extends from plate 55' to one terminal of a secondary coil of a transformer 269'. From finger 59 a conductor 2! extends to a relay coil 2H and from the latter a conductor 2 I 2 extends back to the transformer. The primary of the transformer is connected with line wires L and L by conductors 2I3 and 2M.

A cam follower 69a riding on cam 69 is provided with spaced contact bars 2I5 and 2I6. When cam 69a is in its raised position contact bar 2I5 joins together two conductors 2II and 2I8, while in its lowered position, illustrated in Fig. 1, contact bar 2l6 joins conductor 2I8 withv by the other blade 225 of the switch. Another contact 226 is connected by conductor 221 with the line wire L Switch blade 225 is connected by a conductor 228 with one contact of a. relay armature 229 controlled by the coil 2| I, the'other contact of the relay being connected by a conductor 230 with the line wire L Solenoid 201 is connected by a conductor'23l with the line wire L Knock-out rod 65 for clutch 64 is biased upwardly or to inoperative position by a spring I36. The rod is pivotally connected however with a lever I34 which is arranged to swing upon a, pivot I35. At its opposite end this lever is pivot ally connected with an armature I33 which cooperates with a solenoid I32. When energized this solenoid exerts a pull downwardly upon the free end of lever I34, which depresses rod 65 and thereby serves to disengage clutch 64 when the latter reaches a predetermined point in its rotation, this point being about 180 from the position illustrated in Fig. l and corresponding substantially to that shown in Fig. 2. Solenoid I32 is connected by a conductor 232 with conductor 23I and by a conductor 233 with conductor 228.

Operation.I will first describe the operation of the machine when it is set to perform a tie stitch at each end of a seam. In order to operate the machine in this manner the doublethrow switch is set in the upper position indicated in Fig. 1, that is with the blade 225 engaging the contact 22I. The switch 220 is also closed. The parts are illustrated in Fig. 1 as in their normal condition with no work in the machine. Not ing is moving except the driver I9. Now, when the operator inserts a work blank the finger 59 is separated from the plate 55, thereby breaking the circuit through relay 2. Armature 229 immediately drops and completes a circuit through cam shaft clutch solenoid I32 by way of line wire L conductors HI and 232 to the solenoid and thence through conductors 233 and 228, armature 229, and conductor 230 to line wire L Lever I34 is thereby swung down, compressing spring I36, but rod 65 does not become effective to disengage clutch 64 until shaft 60 has turned through approximately a half revolution to the position indicated in Fig. 2.

The operator in inserting the work piece not only separates contact finger 59 from plate 55 but also pushes the work against trigger I and thereby rotates shafts 8! and 85 counterclockwise, removing the support for extension 81 of lever 89, whereupon the main clutch throw-out rod 2I is pulled down by spring 2Ia and the main clutch engages. Shaft II starts to turn and through gears 63, 62 and 6| rotates shaft at about one-third the speed of shaft I7. Crank Ida starts its movement at the same time. The solenoid 20'! at this time is not energized, and the pin 206 is in its lowered position as shown in Fig. 8, preventing the spring 202 from rotating disk 200 as the arm 28 moves downward to the position of Fig. 9 where it is separated from the pin 203. The arm 28 then starts up again, and when the crank Ida has passed through slightly more than one-half a revolution it will have engaged the pin 293 and moved the disk 20G far enough to disengage the lug 224- from the pin 206. Further movement in the same direction up to the position of Fig. 11 places the spring 202 under added tension.

The cam shaft F0 has now revolved far enough to carry the high point of cam 68 out from under the follower II3, with the result that the drop roll 52 is raised and the drop roll 49 is lowered, thereby gripping the work against the feed roller 22. Also, the follower I00 rides out of the cavity in cam I31 and onto the circular dwell of that cam, thereby pushing the post I02 downward and lowering the trigger I0 far enough to be out of the way of the work. At about the same time furthermore cam 25 permits follower to rise and lift post 95 under the influence of spring 95a, which swings lever 89 about the pivot 8% as a fulcrum. The projection 31 is thereby lifted sufficiently to let spring II2a rotate shafts 85 and BI to return the cam between finger 59 and plate 55.

86 to its original position. The first stitch is now driven.

Immediately after the stitch is driven the first work feed begins. that is to say the pin 203 follows the arm 28 down from the position of Fig. 11 until the lug 204 is stopped by the pin 206. Continuing on, the arm 28 reaches the position of Fig. 12. Since the full movement of the disk is interfered with by the pin a short rotation only of the gears 25 and 24 and the roller 22 takes place. This short feed is indicated by the space I in Fig. 5.

Shortly after this limited feed movement is completed the cam 69 will have rotated sufliciently to lift follower 69a, thereby making inoperative the conlact bar H5 and making the bar 2I5 operative. Solenoid 201 is thereby energized as follows: From line wire L through conductor 23I solenoid 201, conductor 2I8, contact bar 2I5, conductor 2I'I through switch 229, contact 22I, switch blade 225, conductor 228, armature 229 and conductor 230 to line wire L The pin 205 does not rise immediately because of frictional engagement with the lug 224, but as soon as the ratcheting movement of disk 200 has freed the pin from this frictional contact the pin snaps up out of the range of lug 294. The exact time in the cycle when this occurs may vary slightly depending upon the position of adjustment of lug 264, which incidentally controls the length of the space I. The second stitch is now driven.

The cam shaft will now have turned through approximately and at that point the throwout rod 65, which was depressed at the start of the cycle, becomes effective to cause disengagement of clutch 64, thereby stopping the cam shaft in the position illustrated in Fig. 2.

The next feed movement will be a full length movement through a space F as illustrated in Fig. 5, since the pin 225 is not now capable of interfering with the operation of disk 2G0. Stitches and feed movements of uniform length will continue alternately so long as the work is moving When these parts contact again however, that is when the finger runs off the box blank, two things happen. First the pin 225 drops and second the clutch 64 engages. the solenoids 20'! and I32 are deenergized due to the fact that the low voltage circuit is completed by the engagement of 59 and 55, thereby energizing relay magnet 2H and breaking the connection between conductors 223 and 230 through which the circuits for both of the solenoids 20'! and I32 pass. Cam shaft 52 therefore begins to rotate again.

At about this time the next to last stitch is made. Now, since the pin 206 is down the next feed movement will be a short movement f, Fig. 5. Before the last stitch is made the cam 69 will have revolved far enough to again lower follower 69a, making contact bar ZIE effective and bar 2 I5 ineffective in readiness for the next cycle.

While the last stitch is being taken the follower I I3 is riding up onto the high spot of cam 68, thereby shifting the shaft 52 and lowering the drop roll 52 onto the constantly rotating delivery roller 3i. The next feed stroke of disk 200 is inefiective because the work has passed beyond the roller 22. The delivery roller 3! and its drop roll 58 quickly eject the work from the machine. Cams 06 and 6'! now move into the positions illustrated in Fig. l. 5? permits the spring III to raise the post I02, thereby lifting These things occur because the trigger into operative position ready to engage the next piece of work. Cam 6B depresses post 95 and swings lever 89 about its central fulcrum 86, 81, thereby pushing throw-out rod 2l upwardly to disengage the main clutch and stop rotation of both shafts l1 and 60.

It will be apparent therefore that with.the double- throw switch 223, 225 in its upper position and the switch 220 closed the machine operates automatically to make a seam with a .number of uniformly spaced stitches, and one tie stitch at each end. The number of uniformly spaced stitches is dependent upon the length of the work to be stitched, and the operation is automatic in this respect as well as in respect to forming tie stitches at the ends of the seam.

Now, if it is desired to operate the machine without tie stitching to form a seam like that illustrated in Fig. 6, the, operator merely throws switch 223, 225 to its lower position. stitch pin 206 is thereby maintained in its raised position throughout all feed movements of the ratcheting mechanism. It is lowered however for the end of one cycle and the beginning of the next in order to prevent the spring 202 from imparting movement to shaft 11 while the clutch 29 is disengaged. The electrical system is caused to function somewhat differently therefore than when the machine is set to tie stitch. At the beginning of the cycle, when the con-' tact bar 2 i6 is in operative position, the solenoid 201 is immediately energized as follows: From line wire L through conductor 23l, solenoid 2B1, conductor 2l8, contact bar 216, conductor 2l9,

switch blade 225, conductor 228, relay armature 229 and conductor 230 to line wire L The pin 206 however is in frictional engagement with lug When the follower 69a rises during the first period of rotation of cam shaft 60 the solenoid 20! remains energized through contact bar 2l5 as follows: From line wire L through conductor 21", solenoid 201, conductor 2|8, contact bar 215, conductor 2, switch 220, conductor 222,

switch blade 223 and conductor 22'! back to line wire L It remains energized until follower 69a is again lowered during the second period of rotation of the cam shaft which occurs of course after the circuit through relay 2 has been reestablished through finger 59 and plate 55. This breaks the circuit through the solenoid 201 at the armature 229. The tie stitch pin is thereby lowered into position for the next cycle. In other respects the operation of the machine for uniform stitching is the same as for tie stitching.

Adjustment of the length of the spaces between uniform stitches may be brought about by changes in the position of the block on the oscillating arm 28. When however it is desired to reduce the length of the spaces below what is possible by this adjustmentthe spaces between stitches may be further reduced by opening the switch 220, provided the double- throw switch 223, 225 is in its upper or tie stitch position. There is then obtained a seam of stitches uniformly separated by short spaces f as shown in Fig. '7. The opening of switch 220 results'in preventing energization of solenoid 201 at any time, and hence pin 206 remains down and the ma- The tie chineproduces the equivalent of a continuous series of'tie stitches. That the energization of solenoid 201 will be prevented by this means will be obvious when it is observed that a circuit through the solenoid by way of contact bar 2H5 is impossible since the contact 224 is then an idle contact, whilea circuit through the solenoid by way of contact bar US is prevented by the'open switch 220. 7

While in the foregoing description and in the accompanying drawings I have disclosed somewhat in detail a preferred embodiment of my invention, I desire it to be understood that such detailed disclosures arenot to be construed as amounting to limitations except as they may be specifically defined in the appended claims.

Having thus described my invention, I claim: 1. In a machine for. stitching a box side seam, stitching mechanism operating at regularly recurrent intervals, intermittent feeding means tending to move the box blank forward a predetermined distance between successive stitches, meansfor starting said stitching and feeding mechanisms, and means responsive to the movement of the box blank through the machinefor I limiting the extent of feed prior to the last stitch.

2. In a machine-for stitching a box side seam, stitching mechanism operating at regularly recurrent intervals, feeding means tending to move the box blank forward apredetermined distance between successive stitches, 'means for starting said stitching and feeding mechanisms, means responsive to the movement of the box blank through the machine for automatically limiting the extent of feed prior to the last stitch, and other means also responsive to blank movement for stopping the feeding and stitching mechanisms.

3. In a machine for stitching a box side seam,

stitching mechanism, intermittently operating feed rolls for moving the box blank forward a predetermined distance between successive stitches, ratcheting mechanism for operating said feed rolls, means under control of the operator for starting said stitching and ratcheting mechanisms, means functioning automatically for making ineffective a portion of the active stroke of the ratcheting mechanism between the first and second stitches, and means under control of the box blank for disabling said last named means after said first active stroke.

4. In a machine for stitching together two side edges of a box blank, stitching mechanism, an'

by the passage of a box blank through the ma chine, and means under control of said circuit and responsive to movement'of said switch as the rear end of the seam approaches the'stitching mechanism for limiting the extent of the feed movement prior to'the last stitch. v 6. ,In amachine forstitching together two side edges of a box blank,.stitching mechanism, an

electric circuit comprising a yieldable finger arranged. in the path of the work and normally. 1n lcircuit closing position, said =fi'nge'rflb j adapted to be diverted away from circuit closing position by one of said box edges, ratchet mechanism for feeding the work between stitches, and means under the control of said circuit for diminishing the throw of the ratchet mechanism on its feeding stroke.

'7. In a machine for stitching a box side seam, stitching mechanism, means tending to move the box blank forward a, predetermined distance between successive stitches, a finger running upon the box blank, and means responsive to the movement of said finger as it runs off the blank for limiting the extent of the feed movement prior to the last stitch.

8. In a machine for stitching a box side seam,

stitching mechanism, means tending to move the box blank forward a predetermined distance between successive stitches, a finger running upon the box blank, means responsive to the movement of said finger as it runs off the blank for shortening the feed movement prior to the last stitch, and further means set in motion by the movement of said finger as it runs off the box blank for permitting a final stitching operation and then stopping the stitching mechanism.

9. In a machine for stitching a box side seam, means tending to move the box blank forward a predetermined distance between successive stitches, said means comprising a ratcheting mechanism having an idle stroke and a feeding stroke, a spring through which effort is exerted on the feeding stroke, stop means adapted to interrupt the feeding stroke, and means functioning automatically for projecting said stop means into operative position prior to the feed movement preceding the second stitch.

10. In a machine for stitching a box side seam, means tending to move the box blank forward a predetermined distance between successive stitches, said means comprising a ratcheting mechanism having an idle stroke and a feeding stroke, a spring through which effort is exerted on the feeding stroke, stop means adapted to interrupt the feeding stroke, a finger arranged to run upon the blank as it travels through the machine, and means responsive to the movements of said finger for projecting said stop means into operative position prior to the feeding movement preceding thelast stitch.

11. In a machine for stitching a box side seam, ratcheting mechanism for moving the box blank forwardstep by step between successive stitches, a spring arranged to drive said mechanism on its work forwarding stroke, means operative on the idle stroke of the feed mechanism for loading said spring, and means adapted to be interposed to limit the throw of the ratcheting mechanism on the work forwarding stroke.

12. In a machine for stitching a box side seam, stitching mechanism, ratcheting mechanism tending to move the box blank forward a predetermined distance between successive stitches, means for starting said stitching and ratcheting mechanisms with the idle stroke of the ratcheting mechanism occurring during the taking of the first stitch, means functioning to make ineffective aportion of the active stroke of the ratcheting mechanism subsequent to said first stitch, and means responsive to box blank travel for disabling said last-named means after said first active stroke is taken, whereby succeeding active strokes become fully effective.

13. In a machine for stitching a box side seam, stitching mechanism, ratcheting mechanism tending to move the box blank forward a predetermined distance between successive stitches, means for starting said stitching and ratcheting mechanisms with the idle stroke of the ratcheting mechanism occurring during the taking of the first stitch, stop means for limiting the extent of the active stroke of the ratcheting mechanism, and means acting automatically after the first feeding movement is completed to temporarily disable said stop means.

14. In a machine for stitching a box side seam, stitching mechanism, ratcheting mechanism tending to move the box blank forward a 'pre-' determined distance between successive stitches, means for starting said stitching and ratcheting mechanisms with the idle stroke of the ratcheting mechanism occurring during the taking of the first stitch, stop means for limiting the extent of the active stroke of the ratcheting mechanism, electric means functioning automatically after the first feeding movement is completed to temporarily disable said stop means, and an electrical switch responsive to the travel of the work through the machine for shifting said stop means back to operative position prior to the final feed movement of the ratcheting mechanism.

15. In a machine for stitching a box side seam, ratchet means for moving the box blank forward step by step between successive stitches, a spring arranged to drive said mechanism on its work forwarding stroke, means operative on the idle stroke of the feed mechanism for loading said spring, and means functioning automatically, before the second stitch and under control of the work itself before the last stitch for interposing' stop means to limit the throw of the ratcheting mechanism on its work forwarding stroke.

16. In a machine for stitching a box side seam, ratchet means for moving the box blank forward step by step between successive stitches, a spring arranged to drive said mechanism on its work forwarding stroke, means operative on the idle stroke of the feed mechanism for loading said spring, means adapted to be interposed to limit the throw of the ratcheting mechanism on the work forwarding stroke, and means for adjusting said last named means whereby the length of the short feed movements may be regulated.

1'7. In a machine for stitching a box side seam, stitching mechanism, an electric circuit, a switch therefor comprising a spring finger arranged in the path of the work adapted to be diverted from normal position by engagement with the box blank as it travelsthrough the machine, ratchet mechanism for feeding the work between stitches, means under the control of said circuit for diminishing the throw of the ratchet mechanism on its work forwarding stroke effective prior to the second and last stitches of the seam, a switch in said circuit for eliminating the short feeds, and another switch in the circuit for making the short feeds effective between all successive stitches.

18. In a machine for stitching a box side seam, stitching mechanism, an electric circuit, an operator controlled switch therefor, a second switch for said circuit, means for operating the second switch a-predetermined time after the operation of the first switch, ratcheting mecha nism for feeding the work between stitches,

means for diminishing the throw of the ratcheting mechanism on its work advancing stroke, and

therefor, means responsive to the insertion of work into the machine for closing said switch and responsive to the travel of the rear end of the work past a given point for opening said switch, a second switch for said circuit, means for closing the second switch a predetermined length of time after the first switch is closed, ratchet mechanism for feeding the work step by step between stitches, means for diminishing the throw of the ratchet mechanism on its work advancing stroke, and means under control of said circuit for rendering said throw diminishing means inoperative when both switches are closed and for rendering it operative when the first switch is opened.

20. In a machine for stitching a box side seam, stitching mechanism, ratcheting mechanism tending to move the box blank forward a predetermined distance between successive stitches, an electric circuit, switch means for said circuit actuated by the introduction of a box blank into the machine, cam-actuated switch means for the circuit automatically operated after the first stitch is taken, and means under control of said circuit responsive to the operation of both of said switches for limiting the extent of feed movement between the first and second stitches.

21. In a machine for stitching a box side seam, stitching mechanism, intermittently operating feed rolls for moving the box blank forward a predetermined distance between successive stitches, ratcheting mechanism for operating said feed rolls, means under control of the operator for starting said stitching and ratcheting mechanisms, means functioning automatically for making ineffective a portion of the active stroke of the ratcheting mechanism between the first and second stitches, and means responsive to the movement of the box blank through the machine for making ineffective a. portion of the active stroke of the ratcheting mechanism prior to the last stitch. V

22. In a machine for stitching a box side seam, stitching mechanism, feeding means comprising ratcheting mechanism tending to move the blank forward a predetermined distance between successive stitches, a rotating cam, a finger running upon the box blank as it travels through the machine, means responsive to the movement of said finger as it is deflected by the introduction of a blank into the machine for starting said stitchingmechanism and cam, means responsive to the movement of said cam after the first stitch isdriven for making ineffective a portion of the first. active stroke of the ratcheting mechanism, and means responsive to the movement of the finger as it.runs off the advancing blank for making ineffective a portion of the last active stroke of the ratcheting mechanism.

23.. In a machine for stitching a box side seam, stitching mechanism, feeding means comprising ratcheting mechanism tending to move the blank forward a predetermined distance between successive stitches, a rotating cam, a finger running upon. the box blank as it travels through the machine, means responsive to the movement of said finger as it is deflected by the introduction of a blank into :the machine for starting said stitching mechanism and cam, means responsive to the movement of said cam after the first stitch is driven for making ineffective a. portion of the first active stroke of the ratcheting mechanism, means responsive to the movement of the finger as it runs off the advancing blank for. making ineffective a portion of the last active stroke of the ratcheting mechanism, and other means also responsive to the movement of the finger as it runs off the advancing blank for stopping the stitching and ratcheting mechanism.

24. A wire stitching machine comprising a frame, a single wire stitching mechanism mounted on said frame, means mounted on said frame for advancing an article under said stitching mechanism and means mounted on said frame and controlled by said article and operatively related to said stitching mechanism for automatically effecting a short interval between certain of said staples inserted in each article.

25. A machine for stitching wire staples into work pieces comprising a frame, a main drive shaft mounted on said frame, a single 'wire stitcher head mounted on said frame and driven by said shaft, a step by step work piece feeding mechanism driven by said shaft for uniformly spacing staples in said work piece, and means operative by engaging with said work piece for automatically controlling said feedingmecha nism for effecting a short interval between certain ofsaid staples in eachworkpiece.

26. .A machine comprising a frame, a' single wire stitcher head mounted on said framefor inserting staples to form a scam in work pieces passing thereunder, and means controlled by the workpieces for causing the stitcher head to .insert tie stitches adjacent the ends of the seam.

27. A machine comprising a frame, a main drive shaft mounted on said frame, a single wire stitcher head mounted on said frame for inserting staples in box blanks passing thereunder, said stitcher head being located angularly with re spect to said main drive shaft, and means controlled by the box blanks for causing the stitcher head to insert .tie stitches adjacent the ends of the box blanks.

28. A machine comprisinga frame, a main drive shaft mounted on said frame, a single wire stitcher head mounted on said frame for inserting stitches to form seams in work pieces passing thereunder, means controlled byia work piece for causing the stitcher head to insert tie stitches at the end of the seam of said work piece and at the beginning of the seam of the next work piece; and means for adjusting the spacing between said tie stitches and the next adjacent stitches of the seam.

29. A machine comprising a frame, a single wire stitcher head mounted on said frame for inserting staples to form seams in work pieces passing thereunder, and means controlled by a work piece for causing the stitcher head to insert a tie stitch at the end of the seam of said work piece and another at the beginning of the seam of the next succeeding work piece.

30. In a machine for operating upon a work piece to insert a seam of staples therein, a frame, a main drive shaft mounted therein, wire stitching mechanism mounted on said frame and driven by said shaft, work piece conveying mechanism mounted on said frame and driven intermittently by said shaft for advancing the work piece step by step, means under control of a work piece for diminishing the length of the steps be-' tween the last two stitches of that work piece and the first two'stitches of the next succeeding work piece, and under control of said succeeding work piece for causing the conveying mechanism a to resume full length steps after the second stitch has been taken in said succeeding work piece.

31. In a wire stitching machine, a frame, a single wire stitching mechanism mounted on said frame for inserting staples in box blanks passing thereunder, means for automatically advancing the box blanks step by step between stapling operations, and means engageable with and controlled by said box blanks for producing tie stitches at both ends of the blanks.

32. In a machine of the character described, a frame, a single wire stitcher head mounted on said frame for inserting staples in box blanks passing thereunder, said stitcher head arranged at an acute angle with respect to the movement of said box blanks under said head, and means controlled by the box blanks for causing the stitcher head to insert tie stitches adjacent the ends of said box blanks.

33. In a machine of the character described, stitching mechanism operating at regularly recurrent intervals, feeding means for advancing a work piece step by step between stitches, said feeding means having short and long steps, and means set in motion by a Work piece before the last stitch of its seam is driven for beginning short step feeds, and by the next succeeding work piece after the second stitch of its seam is driven 10 to begin long step feeds.

WILLIAM R. SPILLER.

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