US2359770A - Apparatus for removing excess fluid from the printing cylinders of printing presses - Google Patents

Description

Oct. 10, 1944. A. E. LUNDBYE 2,359,770

APPARATUS FOR REIOVING EXCESS FLUIDS FROM-THE PRINTING CYLINDERS 0F PRINTING PRESSES Filed lay -27, 1942' 3 Sheets- Sheet 1 8 axe] ELpndQye,

A. E. LUNDBYE Oct. 10, 1944.

OVING EXCESS FLUIDS FROM THE NDERS OF PRINTING PRESSES APPARATUS FOR REM PRINTING CYLI 3 Sheets-Sheet 2 Filed May 27, 1942 I bExeZ Oct. 10, 1944. LUNDBYE 2,359,770

\ APPARATUS FOR REMOVING EXCESS FLUIDS FROM THE PRINTING CYLINDERS OF PRINTING PRESSES Filed Nay 2'7, 1942 3 Sheets-Sheet 5 fixezznz ndjgp,

Patented Oct. 10, 19

APPARATUS FOR REMOVING EXCESS FLU- 11) FROM THE PRINTING CYLINDERS OF PRINTING PRESSES Axel E. Lnndbye, Springfield, Ohio, assignor to The Crowell-Collier Publishing Company,

Springfield, Ohio, a corporation of Delaware Application MayZ'l, 1942, Serial No. 444,712

14 Claims.

My invention relates to new and useful improvements in printing presses and more particularly to a new and novel mechanism for removing the excess ink from the printing cylinder of a rotogravure printing press.

Heretofore it has been the practice to provide a metal doctor blade for scraping and removing the excess ink that is sprayed onto the rotating cylinder.

These doctor blades in the past generally have been formed from a hard steel plate which scrapes against the relatively soft copper shell of the rotating cylinder.

The combination of the relatively soft copper shell and a steel doctor blade leaves much to he desired. In the first place, the doctor blade may wear unevenly and due to its brittleness may tend to flake or wear in spots. and thus scratch the relatively soft intagliated copper surface of the cylinder, to thus spoil the printing, as even a scratch on the cylinder so small that it cannot be seen by the naked eye will aifect the value of the reproduced print.

Again, the etched surfaces in the copper shell are generally only two-thousandths of an inch deep, and a wear in the surface of the cylinder of five ten-thousandths of an inch will seriously affect the printing, and may even destroy the entire 'intagliated surface.

It is also to be remembered that the ink has no lubricating quality, and thus does not prevent the wearing of the copper cylinder.

In my Patent Number 2,313,830, dated March 16, 1943, for Doctor blades, there is shown and described a metal doctor blade with a graphite lubricant forming a part of the blade, while in the present application there is an entire absence of metal to metal contact, the scraper being formed of a carbon-graphite compound.

One of the objects of the present invention, therefore, is to provide an apparatus in the form of a scraper in which the metal blade is entirely done away with and carbon-graphite units or blocks are held and supported in a novel manner 7 against the printing cylinder of the rotogravure press, to thus effectively remove the excess ink from the intagliated surface and at the same time so reduce the.friction that there is prac-.

tically no wear on the intagliated surface. Thus the printing at the end of the run will he as faithful as the printing at the beginning.

Still another object of the invention is to provide a scraping apparatus wherein a plurality of carbon blocks extend axially of the printing roller so that if it is desired at any time to remove one of the blocks of the scraper, this may be done quickly and easily without disturbing the whole apparatus.

Still another object of the invention is to provide a scraper apparatus wherein the blade or scraper per se is made up of a plurality of like sections or blocks, wherein the pressure on each various elements bear against the surface no portlon or line is missed by the overlapping elements.

Still another object or the invention is to provide an apparatus which may consist of a plurality of sections or blocks of carbon-graphite so mounted in two holders that the blocks of the first holder are staggered with, relation to the blocks of the second holder. thus also assuring a complete'scraping of the cylinder as it rotates beneaththese carbon scraper blocks.

Still another object of the present invention is to provide a scraper to remove the excess ink from the rotogravure cylinders wherein not only are the sections of the scraper-that is, the carbon-graphite blocks-held under pressure, but they are held against removal or dropping from the holder during a change and removal of the sectional plates from the cylinder.

Still another object of the invention is to provide an apparatus for scraping the excess ink from the cylinder of the printing press, which scraper may be reciprocated if so desired so that i even though there might possibly be a hard spot in one of the carbon elements or blocks, it would not always-bear on the same spot on the cylinder,

and thus tend to cut a minute groove in the cylinder.

with these and other objects in view, the invention consists in certain new and novel arrangements and combination of parts as will be hereinafter more fully described and pointed out in the claims.

Referring now to the drawings showing a preferred form andseveral modifications,

Fig, 1 is a fragmentary diagrammatic view on a greatly reduced scale of a rotogravure cylinder;

' the scrapers; and a fountain or casing, together with the paper web and several of its rollers;

Fig. 2 is an enlarged sectional view of the holder for the carbon-graphite scraper element,

and showing a block as in contact with the roto gravure cylinder;

Fig. 3 is a sectional View taken on line 33 of Fig. 2;

Fig. 4 is a side elevation showing the scraper aplparatus in its supported position against the r0 1;

Fig. 5 is a fragmentary end view showing how the apparatus is mounted;

Fig. 6 is a view showing a carbon section against the cylinder, and a tall. for holding the carbon section from accidental loss from the holder;

' eccentric for reciprocating the holder; and

Fig. 13 is a detail of one form of block with the screw eye therein for holding urposes,

Referring now to the drawings and for the moment to- Fig. 1, there is diagrammatically shown the printing cylinder l, a fragmentary portion of the fountain 2, protecting flaps 3, the novel scrapers l, the paper web 5 and its rollers 6, together with the pressure roller 1 and the impression roller 8. The fountain per se and its arrangement forms no part of the present invention.

Referring now to Figs. 2 to 5 inclusive, and for the moment to Fig. 2, there is shown a fragmentary part of the cylinder I, while in close proximity thereto may be seen the scraper 4, together with a carbon element 8 which holder,

together with its elements-or blocks, forms the subject matter of the present invention.

-As may be seen more clearly in Fig. 2. the holder 4 consists of a member formed of metal and substantially inverted U-shape or trough-like in cross section. In otherwords, there are the two side walls and the top portion, the side walls being so spaced as to leave the receptive chamber i extending throughout the length of the holder.

This holder is preferably supported as shown in Figs. 4 and by a plurality of slightly resilient brackets II, which in turn may be bolted to a shaft i2, which shaft in turn may be supported by the adjacent uprights l3. This shaft is, of course, adjacent the printing roller i, so that the carbon-graphite units of the holder about to be desired amount of graphite, so that they present a relatively soft surface to the rotating cylinder, and although effectively scraping the cylinder, they will not mar orcut or scratch the surface of the same.

Of course, a pure carbon clement might be used, but I have found that a carbon mixed with a small percentage of graphite, somewhat softer than the brushes used in electrical appliances,

will thoroughly scrape the cylinder-will not wear too fast, and will provide Just the desired amount of lubrication to prevent serious friction between the scraper and the intagliated surface.

In Fig. 3 I have shown these carbon-graphite blocks 8 as being interlocking at their ends, so that there is no dividing line between the blocks that extends in a straight line completely across the blocks. Each element has the overlapping end l8 and the underlapping portion IS on its other end, while adjoining elements have cooperating portions 20 and 2| to overlap therewith. Thus, when the elements are placed adjacent each other, there is a step formation, as will be readily understood, and any part of the cylinder that 'might not be scraped due to the dividing line on thefront face of the carbon block would be scraped by the rear portion of the carbon block.

- Thus, by overlapping the elements, a complete scraping of the cylinder is assured.

It will be understood that the scraping action here is as efllcient as if the carbon-graphite scraper were one relatively long blade, but in case of a breakage, the entire length of carbon scraper would have to be discarded, whereas in the present instance, should there occur a breakage in one of the blocks a new one may be quickly and readily inserted, as will shortly be explained.

However, it will be understood that one long blade that extends the length of the holder may described will contact with the surfacepof the cylinder I, as may be seen in Figs. 2 and 5.

In Fig. 4 the holder does not appear to-be as long as the printing cylinder, but it will be understood that the intaglio printing surfaces stop short of the ends of the cylinder, so that the holder extends completely'across the intagliated surface.

It will be understood that the manner of sup-.

be used with good effect, and where one blade is used it will not be necessary to have a means for retaining the blade in the holder to prevent it from being sprung therefrom, as is the case when blocks are used,because when the cylinder is lowered the operator may grasp the protruding part of the blade and then lower the cylinder without the blade springing from the cylinder.

It will also be understood that the width of. the doctor blade is exaggerated in the several views merely for the sake of clearness of illustration.

Now again referring to the form of blades that are made up with a series of blocks, it will be seen that these blocks are under spring pressure (to be shortly mentioned) and it is desirable that means be employed to prevent them from being sprung from their holder when the cylinder is lowered to place thereon a different plate. I

therefore employ what I term a tall 22, as may be seen in Fig. 6.

Into each carbon block I preferably insert a small screw eye 23, as may be seen in Fig.'13,

bolts may be of the wing nut type, so as to be quickly turned inwardly or outwardlv of the holder when desired.

Also fitted within the chamber iii thereof may be seen the plurality of carbon-graphite blocks or elements 9, which blocks bear against the relatively soft copper intagliated surface of the printing cylinder i.

These carbon-graphite blocks are made up of the desired amount of carbon together with the so that the lower end of the tall 22 which may be of flexible wire may be looped through the screw eye.

The upper end 28 of the tall 22 may be soldered to a pressure plate 21 (Fig. 8) against which bears the heretofore mentioned bolt 18. There may also be seen the spring 28, and it will be understood that there is a spring, a pressure plate and a tail'for each section or block 8 of the carbon-graphite blade.

To assemble each block, the pressure plate and spring will be assembled and the spring compressed in the fingers, so that the tail may be hooked within the screw eye, and then the pressure plate, spring and carbon-graphite unit will be inserted within the holder 4, as may be readily understood. Then, by turning the halt, the spring may be compressed to exert just the desired pressure of the carbon-scraper block 9 on its cylinder I,

There are a number of advantages in a construction of this kind, the first. of which is the carbon-graphite blade presents but little friction on the copper shell, and still will eflectively scrape the excess ink from the surface.

Again, the pressure may be regulated on each block so that should a foreign object get on the cylinder and pass under the scraper block, the block may move upwardly in its holder and thus prevent damage to the intagliated surface.

Again, by having the tail construction mentioned, the blocks will not spring from their holder on a lowering of the cylinder.

Referring now to a slightly modified form as shown in Fig. 7, the holder 6' is similar to the holder 4 with the exception that in this instance the lower ends of the side walls extend slightly inwardly as at 29 to restrict the opening, and each carbon block has a T-head 30. In this instance the blocks have to be inserted from the side of the holder, and should one break (except the end one) it is necessary to slide the blocks longitudinally of the holder to take out the broken element and then place a new one within the holder, again forcing the blocks together to occupy the space from which was removed the broken block.

However, the advantage of this form is that no tail is necessary, no connection to the pressure plate 3|, nor is it necessary to provide a screw eye in the carbon-graphite block, as the T-head,

as pointed out, prevents the carbon blocks from accidental loss from their holder.

The means of applying the desired-pressure is similar to that as shown in the preferred form.

Referring now to another slightly modified form as shown in Figs. 8, 9, l and 11, it will be seenthat the holder in this instance employs two inverted U-shaped (in cross section), channels, which are welded to each other to form one I and is mounted on the shaft 40 which is sup-' ported by the brackets 39. d It will be noticed that where this double channel holder is used, the car hon-graphite blocks 38 are set in staggered relation to each other (Fig. 9) so that all parts of the surface of the rotating cylinder will be scraped and what ink might be missed due to the division of the blocks on the front face of the scraper will be removed by the staggered blocks that form the rear face of the scraper.

These carbon-graphite blocks will be held against loss by the flexible connections as described with relation to Fig. 6.

As heretofore mentioned, it is possible to use one long carbon scraper that would extend throughout the length of the holder, but the dividing of the carbon-graphite into sectional ele-- ments is preferred.

Also in Fig. -10 I have shown a means .of reciprocating the holder and its scraper blocks or sections, and in this instance I may employ an eccentric ll which may have its center as at 42, and the internal ring or raceway 43, in which will project (Fig. 12) the pin 44, which may be mounted on the end or-continuation of the shaft 40 so that the supporting shaft here acts as the pitman, and on everyrevolution of the eccentric the holder with its two channels 32 and 33 will be reciprocated to thus contact the diiferent points throughout the rotation of the printing cylinder.

By reciprocating the blades it prevents any hard spots or foreign matter in the carbon from continually wearing a track of groove in the intagliated surface.

From the foregoing it will be seen that 1 have provided a scraping apparatus for the printing surfaces of cylindrical printing presses that will eiieetively remove he excess ink and at the same time will not tend to wear the relatively soft copper shell of the cylinder as, although copper is, relatively speaking, soft, the carbon-graphite is softer, and thereiore the scraper will wear before the copper printingsurface, which is just the jopposit'e from when an ordinary doctor blade is used.

It will also be seen that I have provided a holder wherein interlocking carbon blocks may be eiiectively used, and I have also provided a holder wherein the carbon-graphite blocks may be set in staggered relation with each other.

also by mounting these blocks in the manner described, allowance is made for any foreign material that might get on the cylinder, so that if the foreign matter is large enough, only one element will be aiiected, rather than a relatively long blade, and the pressure on these blocks may be individually regulated.

Finally, I have shown an arrangement where the scraper may be reciprocated to thus possibly insure a still greater effectiveness in the scraping action and prevent any minute ridges or scratches being formed in the cylinder by any foreign matter, either on the cylinder or in the carbon blocks, which might cut a track if the blocks continue to press in the one path on the cylinder.

0! course, as the blocks wear-down new ones may be inserted with but little trouble, and in less time than it takes to insert the former type of metal doctor blade.

Having thus described my invention, what I. claim as new and desire to secure by Letters Patent is:

1. In an apparatus for removing excess fluid from the printing cylinders of a. printing press, a holder; a scraper element softer than said cylinders and containing a lubricant mounted in said holder-{means for regulating the pressure of said scraper element against said cylinder; and means associated with the holder and the scraping element to prevent the scraper element from accidental removal from said holder.

2. In an apparatus for removing the excess fluid from the. printing cylinder of a printing press, a plurality of scraper blocks softer than said cylinder and containing a lubricant; a

holder containing the said blocks; the said blocks and the said blocks to prevent the said blocks from accidental loss from said holder.

the said blocks against the rotating cylinder.

4. In an apparatus for removing the excess fluid from the printing cylinder of a. printing press, a trough like holder, aplurality of carbon-graphite scraper blocks mounted in said holder; means for holding the blocks at a' desired pressure against the rotating surface of the cylinder.

5. In an apparatus for removing excess fluid from the printing cylinders of a p'inting press, an inverted trough-like holder; a. plurality of carbon-graphite blocks having interlocking ends ireely mounted in said holder; pressure exerting means associated with' each of said blocks to thereby regulate the pressure of the carbongraphite blocks against the rotating cylinder; and means associated with the holder and the respective blocks to prevent the accidental loss oi the blocks from said holder.

6. In an apparatus for removing the excess ink from the rotating printing cylinder of a printing press, a holder of substantially inverted U-shape having a base and spaced apart side walls; interlocking scraper blocks mounted within said holder; a plurality of bolts threaded through said base, one for each of said scraper blocks: pressure plates within the holder and springs mounted between the pressure plates mounted on said bolts, the respective scraper blocks so that the pressure of the individual blocks may be regulated; and flexible means connecting the respective blocks to their respective pressure plates to thereby prevent the accidental loss of said blocks from said holder.

7. In an apparatus for removing the excess fluid from the rotating printing cylinder of a printing press, a shaft; an inverted trough-like member secured to said shaft; a plurality of scrapers formed of carbon-graphite mounted in said holder; and means for individually regulating the pressure oi. the said scrapers against the said rotating cylinder.

8. In an apparatus for removing the excess fluid from the printing cylinder a printing press, a carbon graphite scraper element; a flexible connection secured to said element; a pressure plate secured to the other end of the said flexible element; and a spring interposed between sion than the opening in. said trough to prevent against the accidental outward removal of said element, and means in the holder for exerting assarro a pressure on the head or said scraper element to urge the scraper element out oi said trough.

10. In an apparatus for removing excess fluid from the rotating cylinder of a printing press, including a holder made up of two trough-like members, the said members each having carbongraphite scraper blocks mounted therein, means for exerting pressure on the respective scraper blocks; and the said blocks in the one troughlike member staggered with relation to the scraper blocks mounted in the second troughlike member.

11. In an apparatus for removing excess ink from the rotogravure cylinder of a printing prcss, a holder consisting of two inverted trough-like members forming an integral structure, the said members each having a plurality of relatively soft, lubricant containing scraper blocks mounted therein; means for exerting the desired pressure in the form of blocks mounted in each of the said channels and adapted to bear against the surface of the printing cylinder; the said blocks in the one channel staggered with relation to the blocks in the second channel; means for regulating the pressure on the individual blocks; and means for preventing the accidental removal of the said scraper sections from the channels on a lowering of the cylinder.

13.,In an apparatus for removing the excess ink from the rotating printing cylinder oi. a printing press. a holder formed oi. a plurality of inverted U-shaped in'cross sectionehannels; a plurality oi soft, graphite-containing scraper sections in the form of blocks mounted in each of the said channels and adapted to bear against the surface of the printing cylinder; the said blocks in the one channel staggered with relation to the blocks in the second channel; means for regulating the pressure on the individual blocks; means for preventing the accidental removal of the said scraper sections from the channels on a lowering of the cylinder; and means for reciprocating the holder.

14. In an apparatus for removing the excess ink from the printing cylinder of a-printing press, including a holder made up of two inverted trough-like members formed into an integral structure, the said members each provided with a plurality of carbon-graphite scraper blocks and adapted to resiliently bear against the sur- -face of the printing cylinder; means for exerting the desired pressure on each of the individual blocks: means for preventing the loss of the blocks from the holder on a lowering of the cylinder; the blocks in the one trough-like member being placed in staggered relation to the blocks in the second trough-like member; and means for reciprocating the said holder axially of said cylinder to thereby assure a'more perfect removal of all excess ink from the said cylinder.

Am E. LUNDBYE.

Patent No. 2,559,770.

canwlmcm's OF CORRECTION.

October 10 19th. AXEL E. LUNDBY'E.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 5, second column, line 21, for "he" before, "excess" read --the--; page h, first column, lines 39 to [#2 inclusive, strike out the words "holder and springs mounted between the pressure plates mounted on said bolts, the respective scraper blocks" and insert instead holdermounted on said bolts, springs mounted between the pressure plates and the respective scraper blocks"; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office. v

Signed and sealed this 2nd day of January, A. D. 1915.,

Leslie Frazer (Seal) Acting Commissioner of Patents;

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