US2984482A - Sheet registering mechanism - Google Patents

Description

May 16, 1961 K. E. KIST ETAL 2,934,482

swam REGISTERING MECHANISM OriginalFiled May a, 1958 4 Sheets-Sheet 1 I N V EN TOR. KHEL .5. K/Sf BY Ja a VflA/OE/VH/V May 16, 1961 K. E. KlsT ETAL 2,984,482

SHEET REGISTERING MECHANISM Original Filed May 8, 1958 4 Sheets-Sheet 2 INVENTOR. K96; 5. K67 BY JHCKE VAM/0EMA/v May 16, 1961 K, E. KIST HAL 2,984,482

SHEET REGISTERING MECHANISM Original Filed May 8, 1958 4 Sheets-Sheet 3 INVENTOR. K/QEL EK/ST y JOCK E V/M/flE/WM/ United States Patent SHEET REGISTERING MECHANISM Karl E. Kist, Brecksville, and Jack E. Vandeman, Berea, Ohio, assignors to Harris-Intertype Corporation Original application May 8, 1958, Ser. No. 734,012. Di-

coded and this application Dec. 14, 1960, Ser. No.

3 Claims. (Cl. 271-46) This invention relates to sheet registering mechanism of a printing press, and is a division of US. application Serial No. 734,012, filed May 8, 1958.

A primary object of the invention is to simultaneously apply suction to the underside of traveling underlapped sheets of a stream at a plurality of transverse points.

A more specific object is to provide for use in connection with front registering mechanism for underlapped sheets of a stream, a plurality of horizontally traveling suckers with valving directly at the sucker mouths, such val-ving being operable to open in response to forward movement of the suckers.

Other objects and advantages Will be apparent from the following description in which reference is made to the accompanying drawings.

In the drawings:

Fig. 1 is a fragmentary elevational view of sheet registering mechanism of the invention illustrating a position of the parts when an underlapped sheet has arrived at the front stops.

Fig. 2 is a view similar to Fig. 1 showing additional partsin the positions they occupy when a sheet is just about to be forwarded to grippers on a cylinder.

Fig. 3 is a view showing the parts of Fig. 1 in their positions at a time the grippers on the cylinder have just closed on a sheet.

Fig. 4 is a plan view taken along line 4-4 of Fig. l with the sheet removed.

Fig. 5 is a view taken looking substantially along the line 55 of Fig. 2.

Fig. 6 is an enlarged detailed elevational view of sheet holddown suckers constituting the invention.

Fig. 7 is an enlarged view taken along line 7-7 of Fig. 3 showing adjustable means for limiting the extent to which the overguide hooks may be lowered to the operative position of Fig. 1.

Fig. 8 is an enlarged view of a connection between certain operating parts and is taken along line 8-8 of Fig. 3.

Fig. 9 is a timing diagram demonstrating the operation of the several parts as it might exist in a commercial machine.

Referring now to Fig. 1, sheets are fed from a conventional pile feeder along a feed table 10 in underlapped stream fashion. The leading edge of each sheet underlies the tail end of the previous sheet. A plurality of continuous tapes 11 pass around a tape roll 12 and drive the stream of sheets down the feed table toward registering mechanism at the forward end thereof just prior to the sheets being fed to a cylinder 13. The cylinder may be an impression cylinder of a printing press or a feed cylinder which subsequently transfers the sheets to an impression or other cylinder. Several idler wheels (not shown) rest on top of the stream as it is fed down the table 10 and cooperate with the tapes 11 to effect frictional driving of the sheets. They feed the sheets to a feed plate 14 the top surface of which is substantially coplanar with and constitutes the forward end of the feed table 10. The feed plate 14 is notched at certain portions as shown in Fig. 4 for purposes which will be described later. Front stops 15 located below the feed plate move from the position shown in Fig. 2 to the position shown in Fig. 1 to intercept the sheets and front register them in a well-known manner. A plurality of overguide hooks 16 have rearwardly extending overhanging portions 17 which maintain the leading edges of sheets against the feed table and prevent their passing over the tops of the front stops 15. The front stops and hooks move to the positions of Fig. 1 prior to the time sheets arrive at the front stops. Before the sheets arrive there, they are taken by reciprocating suckers 18 (shown in detail in Fig. 6). In the preferred form of the invention, these suckers grasp each sheet in turn on its bottom side near its leading edge while the suckers are traveling at sheet speed substantially and lead the sheets beneath the overguide hooks 1 6. Reciprocation of each sucker 18 is effected by an oscillating arm 19.

After a sheet has arrived at the front stops 15 and has had sufiicient time to settle against the front stops, it is gripped by a pair of side guide wheels 20 and urged against a conventional side guide abutment (not shown) to register all sheets identically along one side thereof. The mechanism for operating the side guide wheels has not been shown in detail since it is well understood by those familiar with that art. Suffice it to say that the side guide wheels 20 may comprise a fixed axis lower driven wheel and a movable upper idler wheel which together grip the sheet upon completion of front registration and frictionally drive the sheet against the side guide abutment previously referred to. Upon completion of side guiding, the sheet is pinched by feed rolls and fed by them to the cylinder 13. The feed rolls of the present invention include a plurality of fixed axis driving rolls 21 carried on a shaft 22 located below tht feed table so as to have the peripheries of the rolls 21 approximately coinciding with the surface of the feed plate 14. To minimize the distance of feeding from the rolls to the cylinder 13, the rolls 21 are located as close to the cylinder 13 as is physically possible without interference of parts. A plurality of upper movable feed rolls 23 cooperate with the lower rolls 21 to assist in gripping and forwarding the sheets one by one to the cylinder 13. The upper rolls 23 are idler feed rolls carried on arms 24 mounted on an oscillating shaft 25 which is operated at the proper times by a cam (not shown) on a cam shaft 26.

The sequence of feeding sheets may be shown by comparing the positions of the sheets in Figs. 1, 2 and 3. In Figs. 1 a first sheet S is held in the grippers of the cylinder and its tail end is being removed from the feed table. The tail of sheet S is located slightly to the rear of the side guide wheels 20 at the time a second sheet S arrives at the front stops 15. In practice, the overguide hooks 16 move vertically and lift the tail of sheet S so as to scrape the sheet S therefrom if there is any tendency of sheet S to cling to sheet S and want to pass over the front stops 15. The overhanging portion 17 of each overguide hook 16 is pointed so as to provide a scraping edge for stripping S from S Very shortly after the tail of the sheet S passes the side guide wheels 20 as shown in Fig. 1, the wheels may close and drive the sheet S against the side guide abutment. The wheels 20 maintain their grip on the sheet S until after the tail of the sheet S has passed the transverse gripping line or point of the feed rolls 21 and 23. Any time after the tail of the sheet S passes the feed rolls, the feed roll shaft 25 may be operated to bodily move the idler rolls 23 into contact with the sheet S and positively grip the sheet S In practice, the tail of the sheet S may be a few inches past the feed rolls, but the idler rolls 23 are actually capable of moving into contact almost immedithe front steps ately after the tail of the sheet S passes them. This is possible since the operation of the shaft 25 may occur during only one or two degrees of revolution of the cylinder 13. As a practical matter, however, it is often necessary to have .a gap in a plate cylinder (not shown) of such a-size suflicient to enable rapid installation and removal of the plate. Plate clamps are required to fasten the ends of the plate to the plate cylinder and these plate clamps require adequate room for ease of operation. The gap in the plate cylinder limits the amount of effective printing area and therefore requires a similar gap to be placed in the cylinder 13. The gap is shown at 27. The size of the gap, of course, determines the spacing between sheets as they pass through the press. On the particular press shown, the circumference is approximately 32", about 4" of which includes the gap. The particular feed roll mechanism of my invention will enable this gap to be reduced another inch or so because of the rapidity with which the rolls 23 can be operated upon passing the tail of the sheet S and the closeness with which sheet S may be fed behind sheet S Now, as soon as the rolls 23 grip sheet S the side guide wheels may release their grip. At this time the driving rolls 21 are stationary. The front stops 15 and the hooks 16 are then dropped to the positions shown in Fig. 2 after which time the driving feed rolls 21 may start driving the sheet S toward the cylinder 13. At this particular time grippers 28 carried in the gap 27 of the cylinder are open and are moving into their sheet receiving position shown in Fig. 3. Gauge pins 29 are positioned across the cylinder 13 and are offset laterally from the grippers 28. The sheet S is driven forward by the driving feed rolls 21 and the now-lowered idler rolls 23. The sheet is fed at a slightly faster rate than the speed of the cylinder 13 until the sheet S hits the gauge pins 29, is crowded against them to give a second front registration of the sheet against the gauge pins, and is then taken by the cylinder upon closing of the grippers 28. As soon as the grippers 28 close, the shaft is oscillated to move the idler feed rolls 23 out of contact with the sheet and discontinue their driving action in cooperation with the lower feed rolls 21. The sheet is then transferred by the cylinder 13 to subsequent cylinders of the machine.

Front stop operation Operation of the front stops is effected as follows. The front stops 15 are carried on arms 30 mounted on a shaft 31 having a fixed axis. Each arm 30 is fastened to the shaft 31 by means of bolt 32. A lever 33 is keyed to the shaft 31 and cooperates with a cam 34 through a cam follower 35 carried on the lever 33. The lever 33 is normally urged clockwise about shaft 31 to maintain the follower 35 on its cam 34. This is accomplished by a spring 36 surrounding a rod 37 one end of which is backed by a pin 39 in a frame portion 38. The rod 37 pivots about the pin 39 while the other end passes through a hole in a noddle pin 40 pivotally carried by an extension 41 of the lever 33. The extent of movement of the follower 35 toward the cam 34 is limited by an adjustable abutment 42 which engages an abutment 43 on the extension 41. These abutments limit the uppermost position of the front stops 15. The shaft 31 is located rearwardly of the feed roll shaft 22 and the arms 30 are generally horizontal. This is desirable so that up and down movement of the front stops 15 will be substantially perpendicular to the feed plate 14 rather than parallel to it. By being perpendicularly movable, any slight misadjustment of any one of the front stop arms 30 or play in the parts due to wear will not have a tendency to move a sheet rearwardly. It will be noticed that because of the crowded condition of the parts beneath the feed plate 14, particularly the location of the shaft 22 and the lower feed rolls 21, it is necessary that the arms 30 carrying extend between the feed plate 14 and the shaft 22' and also rolls 21.

Overguide hook operation Operation of the overguide hooks 16 is effected as follows. The cam 34 which operates the front stops 15 through the cam follower 35 may also and preferably does effect part of the operation of the hooks 16 by means of a link 44 connected to a pin on the lever 33. Because of the fact that the feed roll shaft 22 is very close to the cylinder 13, pivotal movement of the hooks 16 is not by itself sufficient to move the hooks between their operative and inoperative positions. A fixed axis shaft 45 carries a bracket 46 for each hook 16 and also a short lever 47. The lever 47 has a pin 48 near its end to which one end of the link 44 is connected. Now, as the lever 33 is rocked, the link 44 through the lever 47 imparts an oscillating motion to the shaft 45 and therefore pivots the overguide hooks 16 through a very small angle. Suppose the parts are at this time in the position of Fig. 1 and the hooks 16 are to be moved below the feed plate 14. This is accomplished by the cam 34 moving the [follower 35 outwardly, thereby pulling rightwardly on the link 44 and pivoting the shaft 45 counterclockwise. The hooks 16 therefore will also move counterclockwise. At about the same time, the hooks 16 are given a downward movement in addition to their pivotal movement. This is permitted by the fact that each bracket 46 permits Sliding of its hook up and down relative to the bracket. Such sliding action is accomplished through means of a cam 49 mounted on the cam shaft 26, a cam follower 50 mounted on a lever 51 pivoted on a shaft 52, a lever 53, which urges a lever 54 carried on a shaft 55 in a clockwise direction which in turn pivots downwardly a lever 56 to the end of which is connected a link 57 pivotally fastened to a member 58 mounted on the bottom end of each of the overguide hooks 16. There is also one such lever 56 for each hook.

An eccentric adjustment 59 shown in detail in Fig. 7 provides the connection between th lever 51 and the lever 53, and a roller 60 workable in a slot 61 in the lever 53 provides the connection between the levers 53 and 54. The adjustment 59 provides for relative angular adjustment between the levers 51 and 53 by means of an eccentric shank portion 62 of a bolt 63. The purpose of such adjustment is to limit the lowermost operative position of the overhanging portions 17 of the hooks to provide for the many different thicknesses of stock handled. When the overhanging portions 17 are in such position, a few thousandths of an inch clearance is provided above the sheet, the purpose of the overhanging portions being to prevent curling or distortion of the leading edges of the sheets while they are being front registered. All of the parts previously mentioned for operating the front stops and the overguide hooks are shown in their operative positions in Fig. 1 and their inoperative positions in Fig. 3. Spring 64, rod 65, noddle pin 66 and pivot pin 67 perform substantially the same as the corresponding parts holding the follower 35 against the cam 34.

Sucker operation Referring to Figs. 2, 5 and 6, operation of the suckers and communication of vacuum thereto is achieved as follows: A pipe 68 extends transversely below the feed plate just forward of the side guide wheels 20. The pipe extends across the width of the press and transmits vacuum to a plurality of the suckers 18. Vacuum comes from a pump by way of a flexible hose 69 controlled by a valve to be described shortly. The suckers themselves are reciprocated from a rearward position shown in Fig. 2, to a forward position shown in Fig. 1. Such reciprocation is along tubular slides 70 shown in detail in Fig. 6. These slides comprise a portion of a valve means directly at the suckers themselves. In operation, when the suckers are in their rearward or Fig. 2 position, vacuum is communicated to the pipe 68 and to the opening 71 of each slide 70. A cross opening 72 communicates at specified times with an annular recess 73 connected to the sucker mouth by mean of holes 74 and 75. In the rearward position, the annular recess 73 is behind the opening 72 so that vacuum in the opening 71 is not transmitted thereto at that time. Upon forward reciprocation of the suckers 18 through means of the arms 19, the recesses 73 coincidewith the openings 72 and vacuum is communicated instantaneously to each of the sucker mouths. In the preferred form of the invention, the suckers are reciprocating forward at sheet speed at the time they take a sheet. The suckers grasp the sheet slightly to the rear of its leading edge.

As will be seen in Fig. 4, the reciprocating suckers 18 lead directly beneath the over-hanging portions 17 of the hooks. They are aligned in a direction of sheet feed with the overguide hooks for best results. Once they reach their foremost position as shown in Figs. 1 and 6, the recesses 73 are beyond the cross openings 71 and now communicate with ports 76 connected to atmosphere. Therefore the suction mouths break their hold on the underside of the sheet after they are under their respective hooks. If perchance one or more of the suckers 18 do not grip the sheet because of curling of the stock or some other reason, the scraping edges of the overhanging portions 17 of the hooks 16 will perform their action to strip the sheet from tending to adhere to the bottom side of the outgoing sheet partially on the cylinder 13.

While the suckers 18 are in their forward position and before they are retracted rearwardly, vacuum to the plpe 68 is disconnected so that the suckers 18 may travel back without disturbing the sheet. Even though the valve formed by the opening 72 and recess 73 are again opened on this return stroke, the fact that no vacuum exists in the opening 71 prevents the application of suction to the underside of the sheet on the reverse stroke. Once the suckers 18 are in their rearward position, the vacuum in the openings 71 may again come on but at that time it is not communicated to the holes 74 and 75- due to the fact that the cross-openings 71 and the recess 73 do not coincide until the arms 19 again start the forward reciprocation of the suckers. Operation of the arms 19 is effected through cam 77, cam follower 78, spring 79 and levers 80 and 81. The two latter levers are fixed to a shaft 82 to which the arms 19 are also fastened. Since the arms 19 are pivotal and the suckers 18 move in a straight line, the connection between each pair is a pin and slot similar to that described between the levers 53 and 54 for effecting the up and down movement of the overguide hooks 16.

Vacuum to the hose 69 comes from a main line 83 from the pump. A valve 84 is shown in Figs. 2 and 5 and comprises a lever 86 which turns a rotor 87 in response to action of a lever 88 due to rotation of the cam 77 which efiects reciprocation of the suckers 18. Lever 88 is carried on a pivot 89 and has its other end carrying a cam follower 90 cooperating with the cam 77 and a spring 91 maintaining the follower 90 against the cam. As the lever 86 carrying the rotor 87 is turned, a hole 92 either connects or disconnects the hose 69 with the line 83. As previously described, it connects the hoses prior to forward movement of the reciprocating suckers 18 and disconnects them prior to the return stroke. If desired, the valve 84 can be dispensed with and vacuum continuously communicated to the slides 70. This however might require that the pipe 68 pivot to permit the suckers 18 to be dropped below the level of the feed plate 14 on the return stroke, or that some form of valve means close off the cross openings 72 when the suckers reach their forward end of the stroke and open them again at the rearward end of their stroke.

6 Timing A timing chart is shown in Fig. 9 to illustrate the relative conditions existing at specified times during the cycle of feeding each sheet. The chart commences at 0, this being the position shown in Fig. 2 where the feed rolls are just about to start a sheet forward. It will be noticed that at that time the hooks are down, the vacuum in the suckers 18 is off, the suckers are on their way back, the side guide wheels 20 have released the sheet, the front stops 15 are below the feed plate 14, and the upper feed rolls are closed on the sheet. By following the timing lines to the right across the chart for each of the parts, the sequence of operation of the various parts can be studied. The chart represents 360 or one complete cycle or cylinder revolution of the press. Since such operation has already been described to a large extent, only certain portions will be re-described as they relate to the chart. It will be noted that at approximately 268 on the chart, the tail of a sheet held by the cylinder 13 has just cleared the side guide wheels 20. Two degrees thereafter, the side guide wheels may close on the underlying sheet and commence side guiding it. Then, at approximately 325 the tail of the outgoing sheet clears the feed rolls. The feed rolls are shown as closing approximately 5 later. As mentioned previously, this may occur in just one or two degrees because of the particular arrangement of the feed rolls combined with the underneath registering mechanism. The only operation required for closing the feed rolls is the oscillation of the shaft 25 which can occur very rapidly. The side guide wheels 20 can move up at approximately 335. Any time after the side guide wheels have released the sheet, and as soon as the front stops 15 and the hooks 16 are moved to their inoperative positions, the feed rolls can commence feeding the sheet. As shown on this particular chart, about 25 is permitted for the operation of the front stops, hooks and side guides to their inoperative positions. As mentioned earlier, some of this time can be dispensed with if desired, since the hooks and stops can be operated much faster than described. However, because of gap size limitations, all the time which is available is used to operate them more slowly.

By utilization of the known principle of underneath registration of sheets, in combination with feed roll sheet feeding mechanism, we can feed sheets in closer succession than heretofore possible. Under-registration permits us to start our front registration at any time within the limits of the speed of the sheets down the feed table by the tapes 11. Commencement of the side registration can occur immediately after the tail of an outgoing sheet passes the side guiding wheels, if desired. If the time it takes the tail of the sheet to move from the side guide wheels 20 to a point past the gripping line of the feed rolls 21 and 23 is sufiicient for side guiding, we can grip the registered sheet almost immediately upon passage of the tail past the feed rolls. The only limitations on how fast we can feed the next sheet, or how close we can feed it to the previous one is determined by the time it takes to release with the side guide wheels 20 and move the front stops 16 and hooks down.

While the preferred embodiment of the present invention has been described in considerable detail, further modifications, constructions and arrangements will be apparent to those skilled in the art and it is hereby our intention to cover all such modifications, constructions and arrangements which fall within the spirit and scope of the present invention.

Having described our invention, we claim:

1. Means for feeding sheets along a feed table to registering mechanism of a printing press, comprising a plurality of suckers, mechanical means interconnecting the suckers for reciprocating the suckers substantially horizontally in the direction of sheet feed and back, said means being operated to close when the suckers reach their forward positions of travel and remain closed until the suckers reach their rearward positions and are again ready to travel forward.

,3.'Means according to claim 2 in'which the sucker valves each comprise a stationary slide, said slides having vacuum communicating thereto through .said additional valve means during the forward travel of the suckers.

No references cited.

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