US1803499A - Cutting and transferring mechanism for printing presses - Google Patents

Description

y 1931- G. DANZER 1,803,499

CUTTING AND TRANSFERRING MECHANISM FOR PRINTING PRESSES Filed May 26, 1928 Patented May 5, 1931 UNITED STATES; PAT NT OFFICE GEORG DANZER, 0F PLAUEIN, GERMANY, ASSIGNOR TO THE FIRM VO'GTLANDISCHE MASCI-IINENFABRIK (VORM'. J. C.'UND H. DIETRICH) A.-G., OF PLAUEN, GERMANY CUTTING AND TRANSFER-RING MECHANISM FOR IRINTING. PRESSE Application filed May 26,1928, Serial No. 280,8 Q-1yand in Germany July 15, 1 927.

My invention relates to rotary (web) printing presses and more especially to improvements in the cutting and collecting de: vices of machines of this kind.

It is a fact well known among practitioners in the art of designing and building rotary printing machines that the problem of transferring the printed web or sheets respectively from the cutting device to the collecting mechanism has always presented considerable difiiculties. The latter have not been satisfactorily overcome in practice with the means usually applied for transferring the sheets, viz needles and travelling endless conveyer bands-because of the paper being mutilated by the punctures from saidneedles and the printed surfaces being liable to become stained and smutted by the conveyer bands.

I have tried to remove the said drawbacks by providing at the grooved cylinder of the cutting mechanism a pair of lateral grippers by which the printed sheets were temporarily held in position near their bottom edge; but it was impossible to hold the sheets by said grippers during the whole. transferring action, viz. until they grippers of the collecting cylinder, because of thelatter being arranged at a distance of several millimeters away from the grooved cylinder of the cutting. mechanism.

Thus by reason of the printedsheets not being securely guided while travelling over the gap between the grooved and the collecting cylinder, it frequently happens with machines running at full speed that because of the web pushing from behindthe sheets are considerably creased and wrinkled, so as to interfere with the proper working of the collecting and folding devices and to entail various other troubles. V

For this reason the attendants were often compelled to slow down the running speed of the cutting and collecting. deviees,land in turn the working speed ing press, thereby considerably-impairing the output of the latter; for reasons-,ofeeononiy however only in comparatively few cases in which rather costly prints were to be delivered without. the slightest mutilation, the grooved cylinder of rotary printing were caught by the y 6, the latter of the whole rotary print:

presses was providedwith a gripping mechanism ofthe kind indicated above for. assisting in transferring the sheets,

The object of my invention is to remove the disadvantages described above and to provideimproved means for safely and posisigned accordingtothis invention i-g. is a cross sectional view of the grooved cylinder of the cutting devlce taken from the end opposite to that ofFig. 1.

The printed webs while jointly travelling downward, as indicated at 1 in Fig. I, are delivered in the usual manner to the cutting mechanism and are cut by the knife carrying. cylinder 2' and the grooved cylinder 3 into single sheets or batches of sheets respecs 1" tively, the latter being clamped at both sides near the cutting line and pressed against the grooved cylinder 3 by a pair of lateral grippers 5 as seen in Figs. 2 and 3'.

A fluted or corrugated roller 7, diagrammatically indicated in, Fig. 1 and revolving at a speed greater than the circumferential speed of the cyl'inders 12, is proyided'for guidingand pushing forward the lower part ofthe sheet towards the collecting cylinder 4 rotating at a ratio equal to that of the cylinders 2 and 3. This ratio of'rotation between the roller 7 and the cylinders 2 and. 3 is. obtained by the employment of a suitable transmission means, such. as a set of gears 6, 33 and 7 indicated by dotted lines in Fig. 1. By the said fluted roller 7 the lower part of the sheet is positivelyv bent around and kept in close proximity to the grooved cylinder 3 so. as to. pass, over a set of guide lingers 8 attached to a bar 9, the latter .ieing mounted on the machine frame. Under the control of said guide fingers 8 the sheets will pass on to the collecting cylinder 6, by the gripping mechanism of which (not shown) the sheets are firmly clamped at their bottom edge and carried forward.

Another set of guiding fingers 10, being attached to a bar 11 which is mounted on the machine frame, is provided for supplementing the guiding action viz. by stripping off the sheetswhenever necessary-from the grooved cylinder Inasmuch as the printed sheets of paper musthe released at their lower end by the lateral grippers referred to abovenot later than at point 15, indicated in Fig. 1, and as the sheets not until having reached point 16--are caught by the gripping device of cylinder 6, nothing would insure their safe delivery from points 15 to 16 except the sheets own rigidity, which however can obviously not be relied upon especially in the case of thin, pliable paper and in view of the lack of stiffness resulting from the curved form of the sheets in transit.

According to this invention an auxiliary set of lateral grippers 17 is provided at the grooved cylinder 3 in addition to the grippers 5 in order to assist in and safeguard the whole transferring action, until the sheets have ac tnally reached the collecting mechanism 6.

The actuating mechanism of both sets of grippers and 17 closely resemble each other in their design. Said actuating mechanism comprises oscillating spindles 18, which are mounted in recesses of the cylinder 3 and have bevel gear wheels 19, attached to them, as seen in Figs. 2 and 3.

Levers 22, carrying sliding rollers 21 at their outer ends and being rigidly mounted on corresponding ends of said spindles 18, cooperate with a curved face-cam 24, which is stationarily fixed on the machine frame and controls the movements of both said levers 22, so that the spindles 18 and gear wheels 19, 20 respectively are given an oscillatory motion at each revolution of the grooved cylinder 3.

The grippers 5 and 17 are mounted on carrier members which are operated by bevel wheels and 26 respectively. the latter being geared to the wheels 19, 20 and mounted in recesses of the cylinder 3; by reason of both sliding rollers 21 running in one and the same stationary face-cam 24: the respective sets of grippers 5 and 17 are opened and closed at corresponding places while the cylinder 3 revolves, viz. being pressed against the cylinder 3 at point 1 and released at 15 in Fig. 1.

The mode of operation is as follows The head gears 19 and 20 are each fixed to the spindle 18, while the gears 25 and 26 are the gears meshing with the said first named gears and which carry the grippers 5 or 17. The levers 22 are crank arms fixed to the ends of the spindles 18 and are each provided with a crank pin on its free ends on which a roller 21 is mounted. The said roller engages an annular cam groove in the stationary member 24. Therefore as the grooved cylinder 3 revolves each spindle 18 will be rotated with the latter but not around itself while the corresponding roller 21 just rolls in one portion of the cam groove. At certain intervals, because of a change in the cam groove, the crank arms will be caused to oscillate and consequently transmit this oscillatory motion to the shafts 18 and consequently the gears 1i) and 20, which, in turn, will impart to the bevel gears 25 and. 26 a partial rotation. As a result thereof the grippers 5 and 17 will be alternately lifted from and lowered onto the bearing surfaces 27.

Means are provided for altering the distance of the grippers of each set so as to cope with the respective requirements in printing webs of different width: As seen in Figs. 2 and 3 a sleeve 29 is slidably attached to the shaft 28 of the cylinder 3 by means of a key 30 so as to rotate with the cylinder 3 and to be capable of being shifted longitudinally to the latter.

Said sleeve 29 and the grippers attached thereto can be fixed by means of a clan'iping screw 31 in any desired. position relatively to the cylinder 3, the latter being provided with an annular recess 33 for obvious reasons.

Abutment members 27 with which the respective grippers 5 and 17 cooperate and the bearings of the bevel gear wheels 26 are also attached to the sleeve 29 andare simultaneously shifted with the latter. The other bevel gear wheels 20, being slidably mounted on the spindles 18 by means of a key 4.0, are held in their proper place by abutting at the rear against an extension 32 of the sleeve. 2S) and by meshing at their business end with the corresponding bevel gear wheels 26.

By the means described above the gripper 5 (at the right) and its actuating mechanism can be shifted to 5iudicatcd in Fig. 2- or to any intermediate place. so as to securelv hold and transfer sheets of papers the width of which range from m to 1 inches.

Various changes and modifications may he made in the design and cooperation of the above described mechanism for transverso ly cutting the printed web and transferring the sheets to the collecting cylinder of rotary printing presses without substantially devi ating from the spirit and the leading ideas of my invention.

Thus e. g. instead of two sets of grippers 5 and 17, designed for safely transferri the printed sheets to the collecting cylinder 6, a series of three or more sets of grippers may be provided on the cylinder 3 for the same purpose.

hat I claim is i. Mechanism for transferring the cut sheets from the cutting cylinders to the collecting device of rotary printing presses comprising a plurality of sets of lateral gripe pers being mounted on one of the cutting cylinders, said grippers being operatively interconnected and adapted to securely hold the cut sheets until the latter have been actually engaged by the grippers of the collecting device.

2. Mechanism for transferring the cut sheets from the cutting cylindersto the collecting device of rotary printing presses comprising in combination a plurality of sets of lateral grippers being mounted on one of the cutting cylinders, said grippers being operatively interconnected and adapted to securely hold the printed sheets until the latter have been actually engaged by the grippers of the collecting device and means for guiding the cut sheets in transit to the collecting device.

3. Mechanism for transferring the cut sheets from the cutting cylinders to the collecting device of rotary printing presses comprising in combination a plurality of sets of lateral grippers being mounted on one of the cutting cylinders, said grippers being operatively interconnected and adapted to securely hold the printed sheets until the latter have been actually engaged by the grippers of the collecting device, and means for guiding the cut sheets in transit to the collecting device, said means comprising a fluted roller, revolvin;- at a speed greater than the grooved cylinder and sets of fingers, adapted to support the sheets and strip 05 respectively the latter from the grooved cylinder. r

i. Mechanism for transferring the cut sheets from the cutting cylinders to the collecting device of rotary printing presses comprising in combination a plurality of setsof lateral grippers being mounted on one of the cutting cylinders, said grippers being operatively interconnected and adapted to securely hold the printed sheets, until the latter have been actually engaged by the grippers of the collecting cylinder, means for guiding the cut sheets in transit and means for altering the distance of the grippers of each set of the respective grippers and their respective actuating members.

6. Mechanism for transferring the cu sheets from the cutting cylinders to the collecting device of rotary printing presses, comprising in combination a plurality of sets of lateral grippers being mounted on one of the cutting cylinders, said grippers being operatively interconnected and adapted to securely hold the printedsheets, until the lat ter have been actually engaged by the grippers of the collecting cylinder, means for guiding the cut sheets in transit, means for altering the distance of the grippers of each set of lateral grippers so as to adjust themechanism to Webs of different Width, said means comprising a sleeve, slidably arranged on the shaft of the grooved cylinder and carrying the respective grippers and their respective actuating members, and means for guiding the cut sheets to the collecting device.

7. Mechanism for transferring the cut,

sheets from the cutting cylinders to the collecting device of rotary printing presses comprising in combination a plurality of sets of lateral grippers being mounted on one of the cutting cylinders, said grippers being operatively interconnected and adapted to securely hold the printed sheets until the latter have been actually engaged by the grippers of the collecting cylinder, means for altering the distance of the grippers of eachset of lateral grippers, so as to adjust the mechanism to Webs of different Width, said means comprising a sleeve, slidably arranged on the shaftof the grooved cylinder and carrying the respective grippers and their respective actuating members, and means for guiding the, cut sheets to the collecting device, said means comprising a fluted roller revolving at a speed greater than the grooved cylinder and sets of fingers, adapted to support the sheets and strip off respectively the latter from the grooved cylinder.

8. Means for transferring the out sheets from the cutting cylinders to the collecting device of a printing press comprising a plurality of sets of grippers mounted on one of the cutting cylinders, and means to operate said grippers to securely hold the cut sheets until the latter have been engaged on the collecting device.

In testimony whereof I afiix my signature.

GEORG DANZER.

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