US3294019A - Rotary printing machine - Google Patents

Description

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V ROTARY PRINTING MACHINE Filed April 13, 1964 12 Sheets-Sheet 6 INVENTOR. NORMAN w. TAYLOR ATTORNEY Dec. 27, 1966 N. w. TAYLOR ROTARY PRINTING MACHINE l2 Sheets-Sheet '7 Filed April 13, 1964 INVENTOR. NORMAN W. TAYLOR We? Q? N f m5 OFEEOPDd mwE 914m TTQRNEY Dec. 27, 1966 N. w. TAYLOR ROTARY PRINTING MACHINE l2 Sheets-Sheet 8 Filed April 13, 1964 INVENTOR. NORMAN w. TAYLOR BY 2 OZ, 2

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ATTORNEY V Dec. 27, 1966 N. w. TAYLOR ROTARY PRINTING MACHINE 12 Sheets-Sheet 10 Filed April 15, 1964 INVENTOR. NORMAN W. TAYLOR ATTORNEY Dec. 27, 1966 N. w. TAYLOR 3,294,019

ROTARY PRINTING MACHINE Filed April 13, 1964 12 Sheets-Sheet 11 FIG. I5

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INVENTQR.

NORMAN W. TAYLOR WKQW ATTORNEY Dec. 27, 1965 w. T R 3,294,019

ROTARY PRINTING MACHINE Filed April 13, 1964 12 Sheets-Sheet 12 n-n-q-r. r

INVENTOR. NORMAN W. TAYLOR ATTORN United States Patent Filed Apr. 13, 1964, Ser. No. 359,128 35 Claims. or. 101-144 This invention relates to a rotary printing machine operating on the planographic principle and having features similar to some of those shown in the US. patents to Ianke, No. 2,547,470 and 2,547,471 and the patent to Curtis, No. 2,165,232, and an object of the invention is to provide a machine on the order of those shown in the said patents with improved automatic sheet supply and sheet starting apparatus and with an improved single lever sheet starting control providing either for selective printing of a single sheet with subsequent automatic stopping, or for continuous printing until stopping is manually brought about by the operator.

One object of the invention is the provision of improved means for mechanically separating the top sheet from the supply stack in such a way as to provide reliable separation of one sheet at a time but without requiring equipment of a complex and expensive nature, and at the same time to provide means readily adaptable to certain existing structure as shown in the said patents.

Another object of the invention is to provide for adequate adjustment of the sheet starting equipment to handle accurately sheets of widely varying weights in a simple and inexpensive manner.

Still a further object of the invention is to provide a simple form of single sheet or continuous operation control and particularly a control of a nature such that it is readily adaptable to the existing control linkages as found in the devices of the said patents.

A feature of the invention is the provision of a corner separator mechanism of improved reliability, designed to be readily adjustable during machine operation to suit the needs of various papers, in cooperation with novel sheet starting means.

A second feature of the invention is the provision of a simple mechanism for determining the degree to which the sheet starting mechanism moves the sheet forward against a positioning stop, and means for readily adjusting the degree of such movement during machine operation.

A third feature of the invention is the provision of both of the foregoing features in a single machine to provide for exceeding flexibility of the machine as to the types of paper which can be handled while maintaining accurate separation and feeding control.

A fourth feature of the invention is the provision of a handle arrangement for controlling paper feed and movable to signal paper starting, but provided further with means to delay the effectiveness of the starting signal until an appropriate time in the operating cycle of the machine such that the printing portions of the machine will be in condition to accept the sheet when fed and will print it properly.

A fifth feature of the invention is the provision of a handle arrangement for controlling paper feed and movable to signal a termination of the paper starting operation, but provided further with means to delay the effectiveness of the termination signal until work in process has been properly completed.

A sixth feature of the invention is the provision of mechanism whereby the motion of the handle to signal paper starting termination also controls blanket and platen cylinder separation motions after a further delay until an appropriate point in the machine operation.

A seventh feature of the invention is the provision of controls of the type mentioned in each of the three immediately foregoing features in association with a single control handle for effecting them.

An eighth feature of the invention is the provision of a singlecontrol handle and means responsive thereto so arranged that motion of the control handle from an off or neutral position in a predetermined direction provides the action recite-d in the fourth feature above stated, and movement thereof back to the off position results in the action recited in the fifth and sixth features above stated.

A ninth feature of the invention is the provision of a control handle and means in association therewith, so arranged that motion of the control handle from an off or neutral position in a predetermnied direction provides the action recited in the fourth feature above stated, and that thereafter the handle is automatically returned to off position resulting in the action recited in the fifth and sixth features stated above, and at a time such that the action recited in the fifth feature is performed and timed in a manner to produce one completely printed sheet only before termination.

A tenth feature of the invention is the provision of a single control handle so arranged that motion thereof from and to the off position in one direction engenders the functions appearing in feature eight above, while motion from and to the off position in another direction provides the functions set forth in the ninth feature hereinabove.

Another feature of the invention is the provision of an improved paper table mechanism giving reliable automatic raising of the pile as paper is used, easy and convenient loading when the supply is depleted, and which is arranged to take its raising instructions from the paper starting rollers, and to coact effectively with the novel corner separators mentioned in the first feature.

Other objects, features, and advantages will appear hereinafter as the description proceeds.

In the drawing:

FIG. 1 is a perspective view of a duplicator according to the present invention with the side covers removed, and showing the parts in continuous run position;

FIG. 2 is a side elevation, partly in section, of the device shown in FIG. 1, but with parts broken away, and showing the parts in the positions normally occupied when l the machine is stopped, and with the blanket cylinder and timing lever at printing cycle start position;

FIG. 3 is an elevation similar to FIG. 2 but showing the parts in the positions normally occupied during continuous running;

FIG. 4 is a central longitudinal section of the machines of FIGS. 1-3;

FIGS. 5, 6 and 7 are schematic detail elevations of the relay and associated parts in various operating positions;

FIG. 8 is a partial longitudinal section of the machine of FIGS. 1 to 3, taken at the inside surface of the near side plate, showing especially the lower portions of the machine, and with the blanket cylinder about 60 ahead of the printing cycle start position;

FIG. 9 is a partial longitudinal section taken similarly to FIG. 8, but showing especially the upper portions of the machine and with the platen and feed yokes broken away and the starting shaft support arm and the table raising linkages removed for purposes of clarity;

FIG. 10 is a view similar to FIG. 9 but showing the paper table and feed portion broken away to a central longitudinal section; and with the starting stroke adjustment omitted to illustrate the operation of the paper starting control elements;

FIG. 11 is a detail section similar to the upper portion of FIG. 10 but showing the parts when the sheet starting control handle its first turned to running position;

FIG. 12 is a view similar to FIG. 11, but showing the parts after the mechanism has been freed to initiate sheet Starting operation;

FIG. 13 is a front elevation of a corner separator element looking from the direction of the paper pile;

FIG. 14 is a right side elevation of the device of FIG. 13 to a larger scale;

FIG. 15 is a fragmentary top plan of the corner separator of FIG. 13;

FIG. 16 is a partial back elevation of the upper portion of the corner separator element of FIG. 14 showing the relationship of the sheets thereto during operation and prior to a starting motion;

FIGS. 17 to 20 are schematic sectional views to a large scale, looking from the same direction as FIG. 13, and illustrating the position of the sheet in various stages of the separating action.

In the drawing there are shown two spaced vertical frame plates and 11 parallel with each other which together with bracing cross rods constitute the main frame of the machine. Ordinarily these frame plates and the machine carried thereby rest on a suitable base or stand indicated at 15. This stand may house a driving motor 16 connected by a belt 17 with a pulley 18 of the printing machine.

The printing machine includes a master sheet-carrying cylinder 20, an offset cylinder 30, and a platen 40 all suitably mounted between the two plates 10 and 11. Between these plates also is supported a mechanism 50 adapted to deliver ink and moisture to the master sheet on the drum 20.

Between the frame plates 10 and 11, I also mount the paper feed mechanism 100 and a paper supply and starting mechanism 300, and behind the platen I provide means for holding a removable receiving tray 120 into which the printed sheets are delivered.

The master cylinder 20 is provided with an axially extending recess 23 in which is mounted a conventional attaching means (not shown) for attaching a printing plate to the cylinder.

Similarly the offset cylinder has a recess 30a with provision for conventionally mounting a blanket on the offset cylinder.

The master cylinder 20 is rotatable on a shaft 21, the ends of which are preferably supported in eccentric bushings mounted in the frame plates 10 and 11, to allow accurate alignment in a known manner. The offset drum 30 is rotatably mounted on an eccentric central portion of a shaft 31 which is mounted in the two frame plates in a manner capable of a partial rotation, by which the position of the offset blanket 33 is adjusted with reference to both the master sheet and the platen as hereinafter described.

The platen 40 is rotatably mounted on an eccentric intermediate portion of a shaft 41, the axial end portions of which are mounted in bearings carried by a yoke 42 pivoted to the plates 10 and 11 at 43 and spring pressed upwardly by a pair of spring units 45 which act against the transverse portion of the yoke distant from the pivot, as hereinafter more fully explained. These spring units maintain proper yielding pressure between the platen and the offset cylinder during the operation of the machine.

The spring units 45 are identical in construction, one being shown in detail in FIG. 9. Each unit includes a spring 44 which bears at its lower end against a fixed cross bar 46 carried by the two frame plates 10 and 11. At their upper ends each spring acts against an adjustable stop 47 on a screw 48, the upper end of which is anchored to the yoke and the lower end of which passes through the cross bar 46, and is provided with a nut 49. These nuts provide adjustable limits for the upward movement of the platen yoke.

The offset cylinder may be released from both the master cylinder and the platen in a known manner by turning the eccentric shaft 31 on which the offset drum is mounted. As illustrated in FIGS. 2 and 3, a cam 34 is secured to the shaft 31 and a spring 39 is connected between this cam and the frame plate 10 to swing the shaft in a counterclockwise direction and thereby move the offset drum away from both the platen and the master drum. Normally the swinging of the shaft is prevented by a latch 37 which is retained in engagement with a tooth 36 on the cam by a spring 35.

Mounted on the shaft 31 for slight rocking movement is a handle 32 (FIG. 1) which is integrally associated with an arm 32a (FIGS. 5 and 6) having an opening 32b loosely surrounding a pin 320 on cam 34. It will be seen that handle 32, via arm 32a driving through the lost motion connection 32b, 320 can move cam 34 to its various positions. Moreover in moving the handle 32 counterclockwise, the end of arm 32a, by striking a pin 37a on latch 37, will cause manual release of the latch 37 before the driving connection between the arm 32a and cam 34 takes effect. Thus, whenever desired the latch 37 may be withdrawn from tooth 36 of cam 34 by an initial counterclockwise actuation of handle 32. This releases the cam 34 and permits the spring 39 to swing the offset drum shaft 31 and bring the offset drum 30 to its inactive position. When it is desired to restore the offset drum to its active position, the operator grasps handle 32, and turns the same in a clockwise direction until the tooth 36 of cam 34 is reengaged by the latch 37.

The mechanism 50 for applying ink and moisture includes a conventional fountain roller 52 and one or more form rollers 55. The latter coact with the master sheet on the drum 20. The form rollers may be manually separated from the master sheet 22 or moved thereagainst by a handle 25 (FIG. 1) operating a control lever 25a (FIG. 2) suitably connected to the form roll mechanism in any conventional manner.

Mounted for rocking movement on the side plate 10 is a main timing lever 72 which has a shaft 73 passing through the plate 10 and integrally connected with an actuating arm 29 which follows the profile of a timing cam rotatable with the blanket cylinder 30. The lever 72 is designed to control a number of the functions of the machine so as to place them in correct time sequence as will presently appear.

In addition the oscillation of lever 72 is used to produce rotation of the ink fountain roller 52 of the ink and moisture system 50. To this end the ink fountain roll has on its shaft a ratchet 76, and lever 72 is 'connected by a link 74 with a lever 75 pivoted about the axis of the ink fountain roll and ratchet wheel 76 which is acted on by a pawl 77 pivotally mounted on the lever 75 and urged toward the ratchet by -a spring 78.

To control the feed of sheets to the printing couple there is provided a peripherally grooved lower feed roller 101, continuously rotated from the machine drive and a coacting grooved upper roller 102. The shaft of the upper feed roller 102 is journalled in a yoke frame 106 which is pivoted at 107 and carries a roller 108 which coacts in a known manner with a suitable cam 109 secured to the offset cylinder so as to effect lowering of the yoke 106 to provide feeding coaction of the rollers 101, 102 at the appropriate time, about 70 degrees, during each cycle. The yoke is urged in a direction to provide coaction of roller 108 and cam 109 by a spring 106a, FIGS. 1 and 2.

The lowering of the upper feed roll, because of the powered rotation of the lower feed roller causes the sheet to be fed forward between suitable guides into th bight of the offset blanket and platen.

Fingers 103 of known type are provided to constitute front alignment stops for the sheet when it is moved into feeding position adjacent rollers 101and 202. These stops are carried on a support 104 r-ockably supported on the frame as by pivoting about the axis of shaft 140 to be hereinafter described. Spring means such as those shown at are provided for holding the fingers in raised position. A pin 111 depending from the yoke 106 abuts a portion of support 104 or a suitable actuator attached thereto and lowers the fingers 103 simultaneously with the lowering of upper feed roller 102 to feed the sheet forward.

After passing through the bight of the offset blanket and platen the printed sheet is delivered to a suitable tray 120 for removal from the machine.

The paper feed roll-s may also be separated whil the master sheet is being prepared for the printing operation. This is conveniently accomplished by using portions of the latch mechanism 34, 35, 36, 37 which is used to separate the offset and master drums during the period of preparation, as heretofore described, and to this end a roller 154 is mounted on the yoke 106 which carries the upper feed roll 102. When the offset cylinder shaft is in its idle position, this roller 154 is engaged by the cam 34 in such manner as to swing the yoke 106 to raise the upper feed roll 102 and hold it raised (see FIG. 2).

The cam 34, it will be seen, performs two functions; it holds the feed rollers separate when the drums are idle, and it retains the blanket drum in its active position when it has been so placed until released by the actuation of the arm 32a to disable latch 37.

Whenever during each cycle of operation, at the proper time for a sheet to be gripped between the feed rollers 101 and 102, a test is made for the presence or absence of such sheet, if the sheet is present the operation proceeds in the normal maner as described. If the sheet is absent, the eccentric platen shaft 41 is automatically turned to withdraw the platen from the offset blanket so that the image on the offset blanket is not transferred to the platen surface, This is accomplished by providing :a plate 130 drivingly connected to the shaft 41. The plate 130 is provided with a tooth 131 which is normally engaged by a latch or a strut lever 132 pivoted at 133 to the frame plate 10. To the lower end of the plate 130 is attached a link 135 drawn toward the right by a spring 136 anchored at its left hand end to the link and at its right hand end to a pin 137 on the frame plate 10. This spring tends to swing the plate 130 and the platen shaft 41 in a counterclockwise or platen-lowering direction which movement is normally prevented by the latch or strut lever 132.

Pivotally carried by the frame is a rod 140 carrying a feeler finger 141 extending into a groove in the roller 101 and beneath the groove in the roller 102. Rigid on the shaft 140 is a rocking lever 142 acted on by a spring 143 which tends to turn the shaft 140 to raise the stop finger. An extension of the lever 142 is connected by a link 144 with the latch 132. The connection as shown is yielding by reason of link 144 being slotted about a pin 145 carried by the latch 132, this pin being connected by a light tension spring 146 with the link which tends to return the latch 132 to active position while the end of the slot acts positively on pin 145 to withdraw the latch.

When during the cycle of operation a sheet should be gripped between the two feed rollers 101 and 102 but before the sheet should reach the bight of the platen and offset cylinders, the plate 130 is acted on by a suitable mechanism about to be described, so that it is given a very slight turn in a clockwise direction, relieving the pressure of the tooth 131 on the strut lever or latch 132. Thereupon the spring 143 tends to swing the feeler finger 141 upwardly and will do so if no paper is present, in which case the link 144 will withdraw the strut 132 from the path of the tooth 131, and the spring 136 will swing the plate 130 counterclockwise thus turning the eccentric platen shaft and lowering the platen to idle position. In this position the platen is free from the blanket, as the downward movement, caused by the eccentric shaft is greater than the slight upward movement allowed to the platen by the stop nuts 40 on the screws 48 and caused by the springs 44.

However, if there is a sheet of paper between the two feed rollers at the time the feeler finger tends to move upwardly, this sheet will bridge the gap across the two sections of the upper feed roller and the finger cannot move up into the freeing position but will be held down by the sheet of paper. This will retain the strut lever in the path of the latch tooth 131, with the result that when the means acting on the plate relieves it so that it tends to turn in the counterclockwise direction it can only turn a very slight distance, that is back to is normal running position shown in FIG. 3, with tooth 131 still resting against the end of latch 132.

The means for turning the plate 130 to relieve the pressure on the latch or strut lever 132 is shown as a pawl 148 on the lower end of the main timing lever 72 heretofore described. This pawl is acted on by a spring 149 tending to maintain it in the position shown in FIG. 2. When the lever 72 is swing by the cam 70, heretofore referred to, in the direction toward the right in FIG. 3, as it does when a new printing cycle is just about to begin, the pawl 148 bears downwardly on a roller 138 carried by the plate 130 while passing across it. The consequent movement of the plate 130 is slight. It is, however, sufficient to swing the tooth 131 free from the strut lever 132. This allows the feeler 141 to test for the presence or absence of paper.

Assuming the paper is absent at the time when it should be present, then the paper detector swings the strut lever into the position shown in FIG. 2 and the spring 136 swings the plate 130 into the position there shown. As the lower end of the lever 72 is swinging toward the left by its spring 87 under the control of the cam 70, the pawl 148 encounters the roller 138 but by reason of the spring 149 may tip on its pivot and thus pass idly to the left side of the roller 138.

Now on the return stroke of the lever 72 the pawl in moving toward the right again engages the roller 138 and carries it and the upper end of the plate 130 to the right, thus bringing the tooth 131 into position above the strut lever 132, and if a sheet of paper is now present between the feed rollers, in position to hold the feeler finger down, the strut lever 132 will be swung into its active position, so that the platen remains restored.

It will be seen therefore that on every cycle of operation a test is made for the presence or absence of a sheet. The feeler 141 and its linkage, which is normally held in idle position by the pressure of tooth 131 on latch 132, is released for action by the slight turning of the plate 130; then if the paper is absent the plate 130 swings into the position of FIG. 2 turning the platen down. If the paper, however, is present the plate returns only a slight distance until its tooth 131 abuts the upper end of the strut lever, as shown in FIG. 3.

To prevent excess inking of the transfer blanket in case a sheet fails to be fed, there is provided means whereby such failure causes the heretofore described mechanism for turning the fountain roller to be ineffective for such cycle of operation. This is arranged by linking the pawl 77 to the plate 130 in a manner holding the pawl idle whenever the platen is turned down, as shown in FIG. 2. To accomplish this, the same link which is actuated by the spring 136 to turn the released platen down to idle position is used.

The link 135 is extended beyond the guiding pin 137. Pivoted to such extension is a link 150 which has a slot 151 extending about a pin '79 on the lower end of the pawl 77.

In the normal position of the parts, with the platen up, the link 150 is idle and the pawl is operated by the cam and link mechanism 72, 74, 75 heretofore described, the same as if the link 150 were absent, the pin 79 simply osci-llating freely in the slot 151. However, when the platen is turned down, by reason of the withdrawal of the latch 132 due to the absence of paper, the link 150 assumes the posit-ion shown in FIG. 2, which brings the left hand end of the slot 151 into position so that when the lever 74 rocks the pawl carrier 75, the pin 79 engages the left end of the slot 151 and can move no further toward the left.

Accordingly, as the pawl carrier swings the pivot of the pawl it simultaneously tips the nose of the pawl to the left so that it cannot engage the ratchet 76. The result is that if during each cycle of operation a sheet is not fed between the feed rolls 101 and 102 the pawl is rendered inactive for that particular cycle of operation, and no fresh ink is supplied to the ink and moisture system.

The description thus far relates in the main to structure found in duplicators heretofore known, and the following description mainly to the improvements which constitute the present invention.

Relay mechanism Referring to FIGS. 2, 3, 5, 6 and 7, there is mounted on the plate 10 on a pivot 201 a central control member or relay 203 which has a plurality of functions which will presently appear. The relay 203, while free on the pivot 201, is impinged upon by a friction device which retains the same in the various positions to which it is moved. In this instance an arm of the spring 35 bearing on the hub of the relay serves this purpose. The depending or trip arm of the relay 203 is designated 205 and carries a roller 207 designed for contact with the arm 32a under certain circumstances. The arm 205 is also connected to a thrust member 209 carrying on its under surface two cam slopes 211 and 213, the former adapted for contact with the edge of a disk on shaft 31 (FIG. and the latter for contact with a pin 215 mounted on plate (FIG. 6).

The free end 217 of the thrust member 209 is disposed between the guide arms of a fork-shaped actuating lever 219 (FIGS. 2 and 3) and is adapted to be acted upon by an abutment arm 221 thereof under appropriate circumstances. As seen, the fork is pivoted to plate 10 at 223- and has a loose driving engagement with link 135 by reason of its hooked lower end 225 which embraces a boss 227 on the reverse side of said link. As can be readily seen, the cam surfaces 211 and 213 act, when trip arm 205 is in either extreme position (both of which represent insensitive positions of relay 203), to hold thrust member 209 high enough to clear abutment arm 221. However, when trip arm 205 is in an intermediate position (FIG. 7), which is identified with what may be termed the sensitive position of relay 203, cam surface 213 functions only partially, and member 209 can drop to a level such that its tip 217 is within the sphere of influence of abutment arm 221.

The relay 203 also includes an upwardly extending power arm 229 which terminates in a laterally directed pointed nose or power cam 231. This cam is designed to receive a driving action at the proper time from the oscillation of main timing lever 72, which accordingly carries a mating cam surface 233. While this cam surface is, for practical purposes, an integral part of the lever 72, in the interests of safety to the mechanism it is actually formed on a separate rocking pawl 235 which is held in operative position by a stiff spring 237 which can permit yielding in the event that some maladjustment allows the cams 231 and 233 to interfere at their tip portions, although this occurs very rarely. It will be noted in FIGS. 5, 6 and 7 that the arcuate path of the tip of the pawl 235 is shown by a dotted line designated P.

Pivotally connected near the end of the power arm 229 of the relay is a combined cam and actuating lever 239 having a pair of downwardly facing cam surfaces 241 and 243 near its distal end. These surfaces are designed to cooperate with a pin 301 which forms the tie between the paper starting control system and the relay 203 and which will be mentioned further at a subsequent point in the description. The pin 301 projects through an opening 10a in the side plate 10, swinging from side to side therein, and in all of its positions underlying the lever 239 which is held thereagainst by a spring 245. The lower end of spring 245 is anchored to a pin 247 which is mounted on and extends through the relay 203,

and acts as a rest for a lock-out member 306 pivoted to the side plate 10 and arranged to fall by gravity towards the pin 301. A notch 308 in the lower surface of lockout 306 will receive the pin 301 when it is in a centralized position and hold it there provided relay 203 is in a lowered position so that rest pin 247 does not prevent lock-out 306 from dropping (FIG. 5). When relay 203 is in raised position the pin 247 serves as a rest for lock-out 306 so that it cannot drop, and pin 301 is free to assume any of its various positions without interference from this source (FIG. 6).

A hook 249 is also mounted on side plate 10, and for various reasons it is necessary that this hook be capable of slight movement. In the first place its vertical level is rather critical and hence it is prudent to provide a mounting which is adjustable for vertical position. In addition the geometry of the parts requires a trace of lateral motion in a certain case. The hook 249 is therefore mounted swingably at its lower end by providing a slot 251 which receives a pin 253. An eccentric 255 is frictionally settable on the pin 253 and coacts with a horizontal lip 257 on the lower end of the hook 249 to accurately position the same endwise. A tension spring 257 provides the combined functions of keeping the hook raised with it lip against the eccentric 255 and urging the hook towards the right against a positioning stop 259 which may conveniently be an extension of the pivot for the lock-out 306, and further allowing the hook to swing slightly to the left under certain conditions. The upper end of hook 249 projects through a slot in the actuating lever 239, where it may engage the upper edge of the lever 239 adjacent the slot. As can be readily seen in FIG. 3, it is thu available to provide a downwardly directed fulcrum against which the lever 239 may react and whereby a raising of the left hand end of lever 239 can produce a slight clockwise rotation of the relay 203 as will subsequently appear.

Paper starting Referring to FIGS. 1, 8 and 9, the top sheet of a stack of sheets S on a paper table 401 is started and fed forward by feed rollers 351. There are preferably two of these rollers, each with a friction tire, mounted on a shaft 353 extending across the machine. The rollers are frictionally slidable on a non-circular central section of the shaft so as to be positionable to suit the requirements of sheets of various sizes and conditions. Each end of the shaft 353 is supported rotatably in an arm 355 indegesgdently rockable on its adjacent end plate by a pivot The shaft 353 has mounted thereon near one end a pinion 359 with which it is connected to be driven thereby in a counterclockwise direction only by an overrunning clutch 361. These are both housed in a casing 363 which is rockably supported on the shaft 361 and which also guides and partially supports a rack 365 which is thereby held in mesh with pinion 359. The rack 365 is reciprocated in proper timed relation with the operation of the cylinders by a lever 303 which is pivoted on the frame at 304 and carries a follower roller 305 riding against a Sheet start cam 307 on the blanket cylinder. The end of lever 303 pivotally connects with and supports the opposite end of rack 365.

The weight of the rollers 351 and their operating mechanism is available to provide a normal force against the top sheet of the paper stack to generate the necessary feeding friction, but since this will often be much more than is actually required, each of the arms is made integral with its pivot 357 which is made to pass through the adjacent end plate and connect with a spiral counterbalance spring (not shown) in a spring barrel 367 which is adjustable to provide the exact amount of counterbalauce effect needed. It will be noted that the ends of shaft 353 can be individually counterbalanced to provide approximately equal pressure on both rollers in spite of 9 the fact that the fioating drive mechanism is present on one end only of shaft 353.

It should also be pointed out that the system embodies sufficient play that the arms 355 are virtually independently movable within certain limits whereby each roller may seek its proper level on the paper stack without interference from the other. I Inasmuch as it is sometimes advisable to adjust the downward pressure of the starting rollers against the paper stack to compensate for certain paper weight differences and/or surface characteristics, the counterbalance spring barrels 367 are normally adjusted to a setting giving a balanced minimum roller pressure, and then a readily adjustable force augmenting system is superimposed. In the form shown, this consists in a pair of light tension springs 369, one connected to each arm 355 and to a control arm at its other end. In FIG. 8 this control arm is shown at 371 with an operating handle at 373. The opposite side of the machine has a similar control arm 374 and both are rigidly connected to a pivot shaft 375 (see FIG. 10) which extends across the machine. The shaft 375 is also connected drivingly to a toothed detent wheel 377 engaged by a detent pawl 379 to retain the desired spring force setting achieved by moving handle 373.

At this point it should be noted that the thrust of rack 365 and the reaction force of the paper against rollers 351 are designed to provide substantially equal opposing moments about the pivotal axis 357 to avoid momentary lessening or intensification of the normal force when the rollers start to move, and to thus provide a smooth, steady feeding action.

Paper table operation The paper table 401 can be raised and lowered to hold the top of a pile of sheets carried by the table at the proper feeding level. The table carries pins 403 and 405 which slide in suitable slots 407 and 409 respectively at opposite sides of the machine frame, one pair at each side. A counterbalance shaft 411 is rotatable in the side plates and has a drum 413 at each end rigidly afiixed thereto. Each drum is connected to a cable 415 which is anchored at its other end upon the paper table. A spiral or other spring (not shown) is provided for giving the shaft 411 a tendency to rotate in a clockwise direction and the spring is so selected or adjusted as to counteract the weight of the table with a full supply of paper thereon. In other words the table must be forcibly lowered under all conditions. The ordinary friction in the system is also such that the spring force provided is not by itself able to raise the table.

Referring to FIG. 8, in order to raise the table automatically as the paper is used thereform, there is provided a toothed wheel 417 drivingly connected to shaft 411 and acted upon by a driving pawl 419 carried by link 421 which is pivoted to rock about the axis of shaft 411 and which is actuated by a link 423 connected to the end of the oscillating cam follower arm 29. A holding pawl 425 is pivoted to the frame and also engages the toothed wheel 417 to prevent lowering motion of the shaft 411 under ordinary circumstances.

The raising action of pawl 419 on toothed wheel 417 is under the control of a movable shroud 427 which is rockable about the axis of shaft 411 and exposes only certain teeth of the toothed wheel to the action of driving pawl 419. The position of the shroud 427 determines how early in its driving stroke the pawl 419 will be allowed to engage the teeth of wheel 417 and hence how many degrees of motion will be imparted as a result of the total stroke. The shroud position is under the control of one of the arms 355 to which it is connected by a link 4Z9. Preferably location of the pivot at arm 355 is made adjustable via screw 431 so that the effective length of the link 4.29 and hence the shroud position can be very accurately set to a position where-by the shroud 427 will just mask out any effect of the driving pawl 419 as the top sheet of the stack S reaches the proper level for feedmg.

The operation of the shroud and the effect of the feed rollers may be in several different modes as determined by the positioning of arms 355. To this end there is provided a position selector 433 which comprises a rock- 'able cross shaft 435 and two actuating fingers 437 with laterally extending pins 439 which enter slots 441 in the arms 355. A knob 442 at one end of the shaft permits manipulation thereof.

When the shaft 435 is so turned that the pins 439 occupy position A (FIG. 8), this is said to be the load position, and the pins then cause the arms 355 to be raised to their highest level with the result that link 429 moves shroud 427 so that it interferes not only with drive pawl 419 but also with holding pawl 425. Accordingly the paper table may now be pushed to its lowest position to receive a fresh stack of paper.

When the shaft 435 is so turned that the pins 439 occupy position B, this is said to be the manual feed position. Here the arms are held high enough to pre vent contact between the starting rollers 351 and a sheet of paper at the normal feeding position. The holding pawl 425 is, however, allowed to engage the toothed wheel 417 to prevent lowering of the table 401 due to manual pressure so that sheets may be fed into the machine by hand from a paper table which remains in a fixed position wherever it is set.

When the shaft 435 is so turned that the pins 439 occupy position C as seen in solid lines in FIG. 8 this is referred to as the automatic feed position and there is no influence of pins 439 on the arms 355. This represents the normal operation with the starting rollers 351 resting upon the top sheet of the paper stack. In this condition the starting mechanism acts as a feeler mechanism as well. When a few sheets have been fed off the top of the stack so as to make it detectably lower, the arms 355 drop enough to let shroud 42 7 recede and allow the driving pawl to catch one tooth of wheel 417 so as to inch the table 401 up slightly and thereby restore the stop of the paper stack to standard feeding level. This, of course, occurs step by step automatically until the stack is exhausted.

The shaft 435 is capable of one other motion in which the pins 439 are turned to occupy a position D; in other words, they are actually forced along a cam surface 443 at the bottom of slot 441 which tends affirmatively to lower the arms 355 against the action of their counterbalance springs in the spring barrels 367. This, of course, can only be done when no pile of paper is immediately under rollers 351. This is referred to as the rapid rise position and is intended to be used for quickly bringing the top of a fresh paper pile up to the standard feeding level after reloading. The effect of lowering the arms 355 is to move shroud 42.7 to a position such that the drive pawl 419 engages the teeth of the wheel 417 early enough in its stroke to cause a driving movement having an angular value equivalent to several teeth at each oscillation of the pawl, thus raising the table to its proper operating position without delay.

Paper starting control Paper starting is activated primarily by the oscillatory motion of lever 303 due to the contact of its follower roller 305 with cam 307 which is insured by a tension spring 309. In the form shown the lever is not a single integral member but, for a reason which will subsequently appear, is made up of two members 311 and 313, both pivoted at 304, and normally held in a predetermined angular relationship by springs 315 together with stop surfaces coacting at 317. They also have potentially coactable stop surfaces at 316 and 318 which come into play only in case there is an overload during the paper 1 1 starting stroke, in which case springs 315 might tend to exceed the designed extension.

Referring to FIG. the motion of lever 303 is indirectly under the control of a handle 319 which pivots about a shaft 320 and which is capable of being held in three positions by a spring-pressed detent 321 activated by a torsion spring 322. The detent can engage in any one of the three notches 323x, 323a and 323s in the handle 319. The erect position shown in FIG. 10 is referred to as the off position in which no paper is to be fed. When handle 319 is rocked to the right so that notch 3230 embraces the detent, it is in a position where continuous separating and feeding of sheets is intended, and when handle 319 is rocked to the left it is intended that one sheet of paper will be fed and printed, and that thereafter the feed will stop and the operation be properly terminated.

As previously indicated, the connection between handle 319 and lever 303 is not direct since it is desirable to have the paper feed start only at a certain point in the machine cycle to avoid improper timing of the sheet starting operation which might otherwise occur, Therefore there is provided between handle 319 and lever 303 an interposer 325 rockable on the same pivot 320 as handle 319 and provided with a pin 301 which extends axially through a slot 327 in handle 319 and also through opening 10a in the sideplate 10 to coact with the various control elements associated with the relay 203 as previously explained. The handle 319 also carries a short pin 302 extending from its reverse side towards interposer 325. Both pins 301 and 302 lie between the radially projected end portions of a torsion spring 329 which, for convenience, has its coils disposed about the pivot 320. The parts are arranged in such a way that whenever the pin 302 is moved by moving hande 319, it loads spring 329 in a direction such that it seeks to move pin 301 in the same direction to thereby line the pins up with each other and the handle.

The opposite end of the interposer is provided with a point 331 adapted to engage the roughened surface of a projection 333 on the portion 313 of lever 303. It is readily apparent that when the parts are in the FIG. 10 position, the interposer blocks the lever 303 from following cam 307 which is now able to touch the roller 305 only at the very highest point. Accordingly lever 303 experiences no oscillation and the starting rollers 351 do not operate.

When the handle 319 is moved towards the right to engage the detent with notch 3230, this will normally bring about a condition as seen in FIG. 11 wherein the ends of torsion spring 329 are spread, but the interposer 325 has not moved due to the pressure of spring 309 acting through members 311 and 313 via spring 315. This pressure maintains the roughened surface of projection 333 against the tip of interposer 325 and prevents its movement. Only when the high point of cam 307 comes in contact with roller 305 will the projection 333 be lowered enough to release the interposer 325 and allow it to follow the handle 319. When this happens, the parts will assume the position shown in FIG. 12 so that the lever 303 is now free to oscillate. A blanket cylinder cycle is now starting during the second half of which the lever 303 will produce a sheet separating stroke of the rack 365 properly timed in relation to the other aspects of the duplicator cycle. This insures that at least one complete inking of the blanket by the master will have occurred before the started sheet reaches the printing point.

In the reverse operation, that is when the sheet separating action is to be terminated, the handle 319 is returned by the operator to erect or off position. This will load torsion spring 329 in the opposite direction and tend to straighten up the interposer 325 along with the handle. Normally, however, if roller 305 is on the lower parts of cam 307, the projection 333 will be in its path and will strike the side of the interposer preventing full return. However, when the high point of the cam 307 comes under roller 305, the projection 333 will be lowered sufficiently to let the interposer snap back to original position and the parts will again appear as in FIG. 10. Thus, any sheet starting operation which has been commenced at the time handle 319 is moved will be assured of being carried properly to completion.

When the handle 319 is moved to the left or in the single sheet direction to place detent 321 in notch 323s, the action of spring 329 and interposer 325 are essentially the same as previously described except for their direction of movement. The primary difference is that the operator does not now return the handle to off position, but means are provided for accomplishing this automatically as soon as the operation of starting the single sheet has been adequately signaled. To this end there is provided on handle 319 an abutment (here shown as a roller) 335, and on member 313 of the lever 303 an appropriately located pushing surface 337. It will be clear by referring to FIG. 10 that when handle 319 is in its leftward position, abutment 335 will be low enough to lie in the path of movement of the pushing surface 337 as it oscillates with lever 303 under the influence of cam 307. Therefore, on the first oscillation after lever 303 has been released by interposer 325, surface 337 nudges abutment 335 and moves it far enough to allow detent 321 to pass the peak dividing notch 3239 from notch 323x, whereupon the spring pressure of the detent completes the action and earns the handle 319 to erect position. Again the following motion of the interposer is delayed by interference with the side of projection 333 until it reaches its lowermost position at the high point of cam 307 and the parts are again in the FIG. 10 position.

Stroke adjustment for sheet starting It has been found in practice that the reliability of feeding, especially as to accuracy of alignment, depends to a large extent on how hard the sheet is driven against the alignment stops 103 by the sheet starting rollers 351. For certain weights and consistencies of paper, it is desirable to have them barely touch the stops, while other types of paper respond much more favorably to a strong push against the stops with consequent noticeable buckling of the sheet. Accordingly the present invention seeks to take this phenomenon into account and to provide apparatus whereby these paper variations can be accounted for by a simple machine adjustment which the operator can make and which permits an accurate setting of the exact length of feeding movement of the sheet starting rollers 351.

Referring especially to FIG. 9, there is provided a disk 501 rockable about the pivot 320'. A portion of the edge of the disk is to be used as an adjustable stop and hence has a slightly spiraled profile, the active portion of which also includes fine teeth 503 for a reason which will presently appear. A handle 505 extends to a convenient location for movement by the operator, and a suitable detent means is provided for frictionally holding the disk in adjusted position. In the form shown, the disk is provided with an edge portion 507 which is a circular arc with a radius sufficient to rub against and slightly deflect the coils of spring 322 which thus has the dual effect of urging detent 321 into active position and also frictionally detenting disk 501.

The upper end of portion 311 of lever 303 is provided with a point 509 which oscillates opposite the toothed spiral portion 503 of disk 501. When the end of spiral portion 503 of smallest radius is opposite the point 509, there is no effect upon the operation of lever 303. However, as the disk is moved to place a portion of greater radius opposite point 509, the disk will stop the swinging of portion 311 before the stroke of portion 313 has been altogether completed, stretching springs 315 slightly, and curtailing the stroke of the rack 365 and hence the amount the sheet is moved by starting rollers 351. Even at the extreme setting, however, surfaces 316 and 318 will not normally come into contact. The reason for providing teeth at 503 is to obviate the possibility that the point 509 could have a c-amming effect on the spiral edge of the disk such that through repeated forcible contacts it might tend to change the setting of the disk. Once the point 509 has found the nearest tooth space there can no longer be any rotational vector applied to disk 501 as a result of such pressure.

It will be noted that the handle 505 can be moved to adjust the length of sheet fed forward by the starting mechanism while the machine is running, for the point 509 is only in movement-inhibiting contact with disk 501 during a small portion of each cycle whenever the interposer 325 is out of line with the projection 333.

Sheet separating The action of separating the top sheet from the pile and doing so reliably for various kinds and weights of paper is achieved according to the present invention in a novel and inexpensive way involving the cooperation of the rollers 351 with means at each of the two corners of the paper pile nearest the feed rollers 101, 102. These means are referred to as corner separators and act partly as front stop means for the pile, and also as means to release the sheet from such front stopped condition in response to forward urging of the sheet. One of these corner separators is shown in detail in FIGS. 10, and 13 to 15 where it is indicated generally by the reference char-acter 45f While in each view the member 450 which is on the left hand side of the machine is illustrated, it will be readily understood that there is also such a member on the right hand side of the machine and which is identical except for being of opposite hand. Each of the corner separators 450 is made of two sheet metal plates. The main plate 451 has a flange 453 turned at right angles thereto along one edge, and at the upper end at the corner formed by said flange is a carefully formed cap configuration 455. This is characterized by five im-' portant features:

(1) The forwardmost portion of the cap joins the plate 451 in a sloping crease 456, and is slightly flattened adjacent the crease 456 as indicated at 457 in FIG. 14 to form a narrow sloping ledge. The crease 456 is not sharp but has a noticeable interior radius.

(2) The ledge 457 and the crease 456 slope downwardly towards the flange 453 so that all three surfaces meet at a corner 459 which is at a lower elevation than the inner end of the crease 456. There is also a slight crease 460 in the flange running rearwardly from this corner on a slight upward slope.

(3) The innermost edge surface of the cap, indicated at 46.1, follows a generally helical path starting at the rearmost point 463 and winding forwardly, first upwardly and then downwardly, in a generally inward direction to merge with the rest of plate 451 at the inner end of crease 456.

(4) The surfaces of the cap portion, and especially the edge 461 have had their corners rounded and are very smooth, and have been treated toresist wear, as by chrome plating.

(5) The length-to-width proportions of the cap element in plan view are also significant, and should be held very close to 8:3. For average paper feeding, the length dimension L in FIG. .15 should be substantially /2 inch, and the width dimension W about 7 inch.

The front wall of the separator just below the cap 455 slopes downwardly away from the flange 453 as indicated at 464 making an angle of a few degrees from the vertical, and the edges of this slope are also smoothed.

The rest of the corner separator is made up of an auxiliary plate 465 attached to plate 451 as by spot welding. The central horizontal section is bent to form a guide loop 467. At the outside end, portions of the plate 465 are extended beyond the flange 453 and bent to provide fingers 469 which form between themselves and the flange 453 a guide groove 471 for a purpose which will presently be explained.

The corner separators are mounted upon a rectangular bar 473 which runs across the machine at the inner end of the feed table 401, the bar 473 passing slidably through the loops 467, whereby the corner separators can be laterally positioned to suit the width of the sheets being fed. This positioning is automatically effected by adjustable side guides 475 which can be moved laterally and set in various positions on the feed table in any well-known manner. The forward edge of each side guide 475 is designed to extend into the guide groove 471 of its corner separator 450* so as to move the same with it whenever a sheet width adjustment is made.

The corner separators 450 are also capable of simultaneous vertical adjustment. The *bar 473 (FIG. 10) has extensions which are slidably mounted in slots 477 in the frame, one of which is shown in this view. At each end of the bar 473 there is a vertical operating member 479 secured to the bar and formed at its lower end with a follower cage 481 which embraces a cam 483. The two cams 48 3 are drivingly secured to a long shaft 485 which is rotatable in the side plates and carries at one end an operating knob 487 (FIG. 1) by which both ends of the bar 4 73 can be simultaneously raised or lowered. A suitable friction detent (e.g., a spring washer, no. shown) is provided to maintain the shaft 485 in any desired adjusted position.

The operation of this vertical adjustment contributes an additional degree of flexibility. It is known that the most effective way to control accurate separation by corner separators is by placing light pressure on the corners of the sheets and causing the sheet to extract itself from this light frictioned retention. Such pressure is frequently provided by springs or weights applied to the separators but I have discovered that it is much more effective to fix the corner separators at a predetermined level and then rely upon the automatic raising of table 401 to apply the proper degree of pressure to the corners by raising the top of the pile to standard height. The reason for this appears to be that the degree of pressure, to provide correct functioning, should be adjusted to take care of different weights of paper and different surface characteristics. Indeed, the same paper under varying humidity conditions has been discovered to require different optimum pressures for the best feeding response. This being the case, it is desirable to render the corner pressure delicately and infinitely adjustable in a simple manner without interchanging parts, and in such manner that the operator can readily change it during running to select the optimum pressure setting for existing conditions. This the present mechanism achieves in an extremely straightforward and low cost manner.

It will be understood that when a pile is in place on the table 401, and the table raising mechanism has brought the table to standard height, the setting of the corner separators will cause a slight downward compression on the pile corners, the degree of which depends upon the level at which bar 473' has been set. This condition is illustrated in FIG. 16 which represents what would be seen by an observer at the position of the feed roll 101 looking toward the left in FIG. 10. The corners of the upper sheet, therefore, are lightly trapped and downwardly deflected by the frictional action of the ledge portion 457 before the sheet starting action begins.

When the rollers 351 begin to turn, the sheet assumes a slight fore-and-aft upward buckle extending across the front margin of the sheet, since the front edge is stopped against the plates 451 or corner separators 450. Very shortly, however, the buckling lateral edges of the sheet, by riding up the helical edges 461 of the caps 455 are cammed laterally towards each other and hence exert a stress which snaps the sheet corners inwardly towards each 15 other until they are finally free of the light frictional pressure applied by ledges 457. Once the sheet corners are free, the sheet, still tending to straighten laterally, forces its edges first against the upper parts of edges 464, and then against the forward part of the curved edges 461.

Since these slope outwardly and upwardly away from the center line in this zone, the sheet cams itself upward and then ultimately feeds forward riding the tops of the caps 455 to proceed towards the feed rollers 101, 102, providing an outstandingly reliable single sheet release action not hereto-fore achievable with separating equipment of this general nature and cost range.

The release action of the corner separators 450 can be adjusted, as previously indicated, by lowering or raising the same with respect to the standard pile height as determined by the raising mechanism for the table 401. This adjustment not only controls the amount of depression of the sheet corners, but also determines the precise width of front stop encountered due to the slope of edges 464. The specific shape of caps 455, heretofore decribed, in cooperation with the slope 464, has provided an arrangement which reacts well for separating papers of many types, and the provision of corner pressure adjustment has extended this range even farther. With the arrangement shown and described it is found possible to feed reliably sheets varying in surface character from bond to parchment to calendered surfaces, and possibly even certain coated stocks. Sheet sizes from 3" X 5" to 11" by 17" have been accurately and reliably separated. Even envelopes are properly fed. One of the main features is the provision of reliable retention for the sheets below the one being separated, which the pressure of sloping ledge 457 against the depressed corners nicely provides, still without impairing release of the top sheet. The sequential action of releasing a sheet is shown in detail in FIGS. 17 to 20, taken in order. These are views looking towards the feed rollers 101, 102 and wherein the sheets of the sheet stack S are sectioned by a plane passing through the points of contactwith the separators. This sequence of positions actually occurs very rapidly so that the corners of the sheet appear to snap out from under the corner separators. However, in spite of this the action is extremely smooth and controlled due to the particular shape of the separators themselves.

While in the foregoing description the use of two corner separators has been described and is normally preferable for the best control, it will be understood that a single corner separator will prove operable in many cases and the invention is not limited in this regard.

Operation Proceeding on the assumption that all of the adjustments previously described have been properly made to accommodate the characteristics of the paper being used, and the motor is running and cylinders turning, but with handle 319 in the off position and the parts generally arranged as shown in FIGS. 2 and 5, the operation of the machine will now be described.

The operator now moves handle 32 to the right which frees the upper feed roll yoke 106 from the influence of cam 34 to permit feeding action whenever called for by the conventional feed cam 109. This also turns shaft 31 to move the blanket cylinder 30 into printing position, and the position thus set is held by the latch 37 acting on tooth 36 of cam 34 as previously described. In addition, the upper edge of arm 32a as it is turned by the handle 32, strikes roller 207 and swings the relay 203 into the FIG. 6 position, whereby pin 247 raises the lookout 306 and the machine is in condition for operation. (It will be noted at this point that if the operator had neglected to move handle 32 first, or at least until he does move the handle 32, no actuation of handle 319 could have been effective to start paper feed because the lockout 306 would then have continued to hold the pin 301 in its notch 308 to prevent lateral motion thereof.)

The operator then moves handle 3 19 to the right indicating that he desires to start a continuous feeding oper-ation. It will depend upon the point in the cycle when this movement is made whether any immediate response is noted. Generally this action will merely cause pin 302 to load the torsion spring 329 which remains in this condition until the high point of the cam 307 is presented to the roller 305 which occurs during a very brief period While the blanket cylinder is in the non-print position (i.e., the gap in, the cylinder is opposite the platen roller.) When this event occurs, the lever 303 is rocked sufficiently to release the pressure on the point of the interposer 325 which then follows spring 329 which moves pin 301 and the interposer to the running position shown in FIGS. 3 and 12. This removal of the interposer occurs at an instant when the leading edge of the blanket is approaching the platen 40, and in the last half of that revolution the rollers 351 are rotated by the action of cam 307 against lever 303 (no longer inhibited by the interposer 325) and acting through rack and pinion 365, 359. Accordingly, sufficient delay has been introduced to insure that the blanket has had at least one complete contact with the inked master on cylinder 20 before a sheet is presented to it for printing. This motion of rollers 351 starts forward a sheet of paper in time to meet the lead edge of the blanket at the printing point by causing the separating action heretofore described when the top sheet is pressed forward by the rollers 351 against the corner separators 450. The thus started sheet is, of course, moved between the conventional feed rollers 101, 102 and against the stop 103 which act in the known manner to forward the sheet in time with the printing action of the cylinders. As the machine continues its operation, of course, one sheet is started, fed forward, printed and delivered for each cycle of operation, and the parts will appear as shown in FIG. 3.

It will also be noted that motion of pin 301 to the right, just mentioned, also allows actuating lever 239 to drop so that it latches under hook 249 in readiness for a subsequent motion which will be hereinafter described.

When the operator decides to bring the continuous printing operation to an end, he merely moves the handle 319 back to the upright or off position. Again this will normally produce no immediately noticeable change in operation, since one complete cycle after that one already in progress is designed to be completed before the machine shuts down in order to print and deliver the sheet which has been or will be placed in ready position against stops 103 by cam 307 during the last half of the current cycle. Normally this will merely cause pin 302 to load spring 329, but in the other direction. When the high point of cam 307 finally moves lever 303 far enough to make room for the interposer 325, the gap in the blanket cylinder will be opposite the platen cylinder and the last sheet will be feeding into printing position. This is the instant when pin 301 is moved back to central position by spring 329 and signals the start of the last printing cycle, the interposer now preventing oscillation of lever 303 and hence preventing the starting of any more sheets.

It will also be noted that the movement of pin 301 to central position has cammed upwardly the free end of actuating lever 239 which, by reason of the fulcrum furnished by the hook 249, causes the relay 203 to rotate a few degrees clockwise from its insensitive running position placing the parts in the sensitive position of FIG. 7. This slight rotation of relay 203 to sensitive position allows the thrust member 209 to change the relationship of its cam surface 213 to pin 215 whereby its free end 217 drops far enough to be within the sphere of influence of abutment arm 221.

The parts are now in condition for the final print cycle to take place. As, this cycle proceeds, the last sheet is fed through between the cylinders and is printed and finally delivered. Since the interposer 325 has prevented the starting of another sheet d ring this last cycle, there will

Claims (1)

1. IN A PRINTING MACHINE, INCLUDING PRINTING MEANS COMPRISING A ROTARY PRINTING CYLINDER, MEANS FOR REPEATEDLY APPLYING INK TO SAID CYLINDER IN AN IMAGE PATTERN, MEANS FOR STATING THE TOP SHEET OF A SUPPLY OF SHEETS AND MOVING THE SAME FORWARD INTO THE CONTROL OF THE PRINTING MEANS, AND A TIMING CAM MOVING IN TIMED RELATION WITH THE PRINTING CYLINDER, THE IMPROVEMENT WHICH COMPRISES: A PRINT CONTROL HANDLE SETTABLE IN EITHER A NON-PRINTING POSITION OR A PRINTING POSITION AND EFFECTIVE WHEN MOVED INTO THE LATTER POSITION FROM THE FORMER TO PROVIDE A MECHANICAL SIGNAL THAT INITATION OF SHEET STARTING IS DESIRED; AND MECHANICAL MEANS RESPONSIVE TO BOTH SAID STARTING SIGNAL AND THE ACTION OF SAID CAM FOR CAUSING OPERATION OF SAID SHEET STARTING MEANS BUT DELAYING THE SAME FOR A FRACTION OF A REVOLUTION OF THE CYLINDER AFTER SAID HANDLE MOVEMENT UNTIL TREATMENT OF SAID PRINTING CYLINDER BEGINNING AT THE LEADING EDGE THEREOF HAS BEEN STARTED BY SAID INK APPLYING MEANS FOLLOWING SAID SIGNAL, AND THEREAFTER INITIATING OPERATION OF SAID SHEET STARTING MEANS IN TIME WITH THE CYLINDER FOR A PRINTING ROTATION THEREOF

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