US1806865A - X x x x x - Google Patents

Description

y 1931. A. w. RANGER 1,806,865

PLATEN PRINTING PRESS Filed Aug 2, 1930 4 Sheets-Sheet 2 Fig. 6.

fizz/9227221 A )1. 18215981 y 6, 1931. A. w. RANGER 1,806,865

PLATEN PRINTING PRESS Filed Aug. 2, 1930 4 4Sheets-Sheei s U I I Zizuen/ar A 'Jmial del Affq.

May 26, 1931. A. w RANGER 1,806,865

PLATEIN PRINTING PRESS Filed Aug. 2. '1950 4 Shets-Sheet 4 lira-Q1130? ,4 I ml alz ge 7 l at ent ed May 26 UNITED STATES PATENT oFFics i ARTHUR WI LARD Banana, .01 onnoN, ENGLAND PLATEN rrun'rnve rnnss Application med Au usta, 1930; SeriaINo. 472,658, and in Great Britain January 27, 1980.

The invention relates to platen presses in which the sheets are carried from a pile to the platen, held there during the printing operation, removed alter printing and'delivered by means of .radial,ar1ns'usual -ly two provided with grippers, the arms roe tating intermittently, for example, through 90 at each operation. V

To obtain perfect registration with such" mechanism is extremely diflicult and the slightest irregularity in the mechanism determining the position of each gripper arm on the platen or irregularity in the stacking of the sheets, on the pile, or unequal wear of mechanism driving the gripper. arms will interfere with the registration, as no means integral with the platen are provided for definitely registering the'sheet.

The present invention insures accurate registration irrespective of theabove difficulties, and it is characterized therein that the grippers are adapted to release each sheet momentarily while it is on the platen prior} 7 to the printing operation, and that registration of the released sheet is theneliected by means of one or more lays which are adapted to be moved to engage with the sheet and therebyset it in a determined position where it remains during the-printing operation.

The known means maybe adopted for intermittently rotating the radialgripper arms to bring the sheets on to .the'platen and to remove the printed sheets theref-roim'and the known mechanism may Joe used to open and to close the grippers, such mechanism, however, being modifiedso as to effect an .addi- I tional opening of the grippers of the radial gripper arm which is forthe timebeing over the platen in order 'to'releasethesheet and tion by the lay or lays; v

The-lay or lays are so arranged, for example, they may be so moved before the de-. positing of a sheet on the platen andafter they allow each gripper arm to move on to, overand away vfrom the platen, the grippers seizingthe printed sheet and carrying it away and delivering it in the usual manner.

Thus the registration of the sheets -is efnism andthe registering lays.

to permit of it being set into correct registrathe registering and "printingthereof, -.that

fected by means which are independent oi the gripper arms, so that slight variationsin the positions of the gripper arms, or in the relation of the sheetsto them when carried to the platen, have no effect on the registration.

The invention is further characterized byplaten press which sometimes may have to be used for printing several sheets at a time or on other work whichdoes not require perfect registration. The accompanying drawings illustrate an example of lay registering mechanism for a platen press according to the invention.

Figure lis a plan (as seen when looking perpendicular to the plane of the platen) of the platen with radial gripper arm mecha- Figilre 2 isa plan partlyinsection showing part of the main shaft and the cams thereon for operating the gripper opening imd closing mechanism and for operating the ays. L I V Figure is a view, on a larger scale, of part ofthe lay mechanism.

Figure 4' is'a side view corresponding .to Figures 1 and 2. V Y

f Figure 5 is a cross section of one gripper arm and the side lay. V

Figure'6 is aaplan of part of 'agripper blade. a i a Figure 7 isa view (seen when looking per- 7 pendicular to the platen) illustrating mechanism{ :forxrendering the lay registering mechanism inoperative. i Figure 8 being acorresponding plan ofthe upper portion of same. 7

Figures 9. and 10 ,are, respectively, aside view and a:view,seen when looking perpendicular to the platen, ofmodified mechanism for operating the registering lays. g

Figures 11 and 12 are sectional views illus tratin two examples of fine adjustment devices for the lays. T

Figure 13 is a sectional side view illustrating another form of lay.

The invention is illustrated as applied to a platen press in which two grippers arms 1, 1, are mounted on a carrier 2 fixed to a shaft 3 and rotated intermittently through 90, the gripper arms 1, passing successively over the platen 4 to bring sheets thereon and to remove the printed sheets therefrom. Each gripper arm 1 has the usual slotted gripper blade 5 for ripping the sheet between it and the sharp e ge 6, except that the slots 7 preferably have bevelled edges 8 to avoid the corners of the sheet catching in these edges.

It is assumed that the intermittent rotaion of the shaft 3 is effected as usual by bevel gearing in a gear case 9, the operating shaft 38 of these gears being driven in the usual manner from the main shaft of the machine. These parts being well known, there is no necessity to illustrate them.

The gripper blades 5 are opened intermittently by a cam 10 freely mounted on the shaft 3 and oscillated by a slotted cam 11, Figure 4, on the main shaft 12, through the medium of a bell crank lever 13 which is pivoted at 14, has a pin or roller 15, in the slotted cam 11 and is pivotally connected at 16 to a rod 17 which is pivotally connected at 18 to an arm 19 fixed to the cam 10.

Each gripper blade 5 is mounted on a hinge pin 20 which has an arm 21 pivotally con nected at 22 to a rod 23 which is pivotally connected at 24 to a lever 25 which has a pivot pin 26 freely mounted in the carrier 2 and has a lever 27 provided with a roller 28 en- 7 gaged by the gripper opening cam 10. A

spring 29 tends to close the gripper blades 5. It is coiled about a rod 30 which )asscs through studs 31 pivotally mounted on the levers 25. I

This is known mechanism for opening and closing the gripper blades, but in order that the gripper blades shall be opened to release each sheet momentarily while it is on the platen immediately before registration is effected and shall close again to remove the printed sheet from the platen, the usual oscillatory gripper opening cam 10 has an additional rise 32 and the usual slotted cam 11, Figure 4, for oscillating the oscillatory cam 10, has an additional rise 33. The rise thus gives the required additional oscillation to the cam 10 and the rise 32 opens the gripper blades of that gripper arm which is at the platen.

In order to register the sheet when so released momentarily on the platen 4 a side lay 34 and bottom lays 35 are provided to engage respectively with the side and bottom edges of the released sheet. 3

The side lay 34 is fixed on a shaft 36, Figure 3, which is free to oscillate in a bearing 37 which is cast on the side of the platen 4 and a bracket 39 which is fixed by screws 40 to the side of the platen. A collar 41 and a bevel wheel 51 prevent endwise movement of the shaft 36. A coiled spring 43 rotates the shaft 36 in one direction to hold the side 34 against a fixed stop such as a stud 44 which is screwed into the side of the platen 4.

The bottom lays 35 are fixed on a shaft 45 which is mounted to oscillate in the bracket 39 and in a bearing 46 which is fixed by screws 47 to the platen 4. A spring 48 rotates the shaft in one direction until the shaft is arrested by a stop so as to hold the bottom lays 35 adjacent to the bottom edge of the platen 4. Each bottom lay 35 pre erably has a light spring blade 49 for engagement with the face of the sheet. A stiffer blade 96 prevents undue yielding of the blade 49. i

In the example shown in Figures 1 to 4, the two shafts 36 and 45 are connected by toothed bevel wheels 50, 51, to ensure that the side lays 34 and bottom lays 35 shall be operated in unison. The shaft 45 has a crank having a roller 53 which is engaged intermittently with a cam 88 on a rocking lever 54 which is pivoted at 55 and is held by a spring 56 with its roller 57 in engagement with a cam 58 on the main shaft 12. The

crank 52 has a lug 90 for engagement with the bracket 39 to act as the stop above referred to for arresting the bottom lays in the registering position.

As a sheet is brought on to the platen 4 by one of the gripper arms 1, into an approximate printing position, the additional rise 33 on the slotted cam 11 and the additional rise 32 on the gripper opening cam 10 effect the momentary release of the sheet. Meanwhile the cam 58 has allowed the side lay 34 and the bottom lays 35 to move towards the platen under the action of the springs 43, 48, to engage with the side and bottom edges of the released sheet and thereby set it accurately in its correct printing position, that is, to register the sheet correctly. It is advisable to allow a certain amount of back lash (clearance) between the teeth of the bevel wheels 50 and 51 to allow the side and bottom lays to be firmly pressed by their springs into registering position in the event of one reaching that position before the other.

It will be appreciated that the lay mechanism described is independent of the mechanism which rotates the gripper arms so that inaccuracies in this latter mechanism have no effect on the registration of the sheet which is perfectly affected by the lays.

The sheet is accurately registered by the lays and is held by them during the printing operation. After the printing has been effected, the additional rise 32 has left the roller 28 and allows the gripper blades to grip the sheet again to remove it from the platen after the printing operation and deposit it on a pile in the usual manner. It

will be understood that the cam 58 through if ion eos-sea the medium of the rocking lever 54 and crank 52 rotates the lay shafts 36 and to remove the lays 34, 35 from the platen before the sheet is removed therefrom. I V

When it is desired that the platen press may be used for printing on several sheets simultaneously and with work which does not require accurate registration, means are provided by which the lay mechanism may be rendered inoperative. such means is illustrated by Figures 7 and 8 wherein the additional rise 32 of the gripper opening'cam 10 is secured to a block 59 which is pivoted on a pin 60 on the side boss of the cam. The block 59 also has a projection 61, I 7

When the block 59 is in the position shown against a stop pin 76', the additional rise 32 is in the operative position over the cam 10. When the block is turned about the pin 60 through 90, the rise 32 is in an inoperative position away from the cam 10 and the projection 61 engages under the segment 62 which is formed on a lever 63 which. ispivoted at 64. The segment 62 has a handle 65 by which it can be raised slightly to permit of the projection 61 being placed under it. The lever 63 is slotted at 66 to receive a pin 67 on the end of the rod 68 guided ina lug 69 and having a blade 7 0 at its lower end. A spring 71 is interposed between the lever 63 and a collar 7 2 on the rod 68.

When the projection 61 is set under the segment 62, the lever 63 depresses the rod 61 and the blade engages in a slot 7 3 in the collar 41 when the side lay 34'is moved away from the platen, the blade 7 0, then prevent ing the lay shaft 36 rotating under the action of its spring 43, Figure 3, when the lever 54 releases the roller 53. Consequently the lays 34 and 35 will not be operated.

Figures 9 and 10 illustrate a modification of the lay operating mechanism; In this example the bottom shaft '45 is operated by the crank 52, roller 53, a cam 88 and lever 54,

as in the example above described, but'the side lay shaft has a bevel wheel 74meshing v with a bevel wheel 75 which is fixed on a spindle 84 mounted in a' boss 85 on the bracket 39, the spindle 84 having a crank 86 provided with a roller 87 which is engaged by a cam 89 on the lever 54.

By these means the side lay and the bottom 7 lays are independent of each other and may be timed to move one in advance of. the

other instead of simultaneously by suitably shaping the cams 88 and 89. This may be advantageous with sheets of certain shape and size.

Fine adjustment devices may be fitted on the lays to determine or vary the final registering positions of the lays. For example, in Figure 11 the side lay 34 is provided with a finely threaded screw '77 which abuts against the edge of the platen 4 Y (or against An example ofthe 'stop 44, Figure The screw 77 has a collar 7 8 and the spaces between the collar 78 and-the head of the screw and :theadjacent sides of the lay 34 allow for a certain adjustment.

Figure 12 shows an example of adjustable bottom lay. The lay 35 has a spring? 9 fixed at 80 to. the lay. It carries a light bow spring 81 for engaging with the face ofthe The shoulder 82 0f the spring '79. engages with the edge of the sheet. A finely threaded set screw 83 affords adjustment of the spring 7 9 and, therefore, of its sheet.

shoulder 82.

"It sometimes happens (especially when dealing with very thin sheets of paper) that the bottom edge of the sheet sags or curls over the lower edge of the platen owing to its momentum at the moment the gripper arm stops with the sheet over the platen. This results in the edge of the paper buckling as it is not in a position to be engaged properly by the bottom lays and, therefore, it is desired that the lower edge of the sheet shall be supported and, if necessary, straightened out just prior to the registration. i In order to avoid the bottom edge of a sheet sagging or curling over the bottom edge of the platen, such as might occur with a very thin sheet 'of paper owing to its momentum at'the moment a gripper arm is arrested with a sheet over the platen, each bottom lay 351nay be provided with a light spring blade 91, Figure 13, which is always in contact with the edge of the platen and yields as the lay 35 advances towards'the platen. i

I claim: 1 V 1. Ina platen printing press having radial arms provided with grippers and adapted to 'be partially rotated intermittently in the tom edges of the platen and means for move ing said laysrelatively to the platen.

. 2. Inca platen printing press having radial arms provided with grippers and adapted to be partially rotated intermittently inthe plane of the swinging platen to bring sheets onto andremove them from the platen, an

"oscillatorycam for opening and closing said grippers and a rotary cam for oscillating said oscillatory cam, additional rises on said cams for effecting an opening and closing of the grippers while at the platen,lays adjacent to said platen and means for moving said lays relatively to said platen for the purpose of registering each sheet when the grippers are open while at the platen, substantially as hereinbefore'set forth.

3. In a platen press having gripper opening and closing means and lays for registering each sheet on the platen as claimed in claim 2, means for holding the lays in inoperative positions, and an additional rise, on the oscillatory cam for opening and closing the grippers of each arm while at the platen, which is adapted to be moved out of its operative position relatively to the gripper opening and closing mechanism and into a position to operate said means for holding the lays in inoperative positions substantially as and for the purpose hereinbefore set forth.

4. In a platen press having radial arms, intermittently rotated in the plane of the swinging platen, provided with grippers for bringing sheets onto and off the platen, means for opening and closing the grippers of each arm when at the platen, lays adjacent to the side and bottom edges of the platen, means including springs for moving said lays towards the platen when the grippers at the platen are open, means for arresting said lays in determined positions when so moved, and means for moving said lays away from the platen against the action of said spring, substantially as and for the purpose hereinbefore set forth.

In a platen press having radial arms, intermittently rotated in the plane of the swinging platen, provided with grippers for bringing sheets onto and ofi the platen, means for opening and closing the grippers of each arm when at the platen, lays adjacent to the side and bottom edges of the platen, means including springs for moving said lays towards the platen when the grippers at the platen are open, adjustable means for arresting said lays in determined positions when so moved, and means for moving said lays away from the platen against the action of said spring, substantially as and for the purpose hereinbei ore set forth.

6. In a platen press having radial arms, intermittently rotated in the plane oi the swinging platen, provided with grippers for bringing sheets onto and of? the platen, means for openin and closing the grippers of each arm when at the platen, shafts adjacent to the side and bottom edges of the platen, lays on said shafts, springs for rotating said shafts to move the lays towards the platen when the grippers at the platen are open, and means for rotating said shafts against the action of said springs to move the lays away from the platen, substantially as and for the purpose hereinbefore set forth.

In testimony whereof I have signed my name to this specification.

ARTHUR WILLARD RANGER.

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