US1901284A - Printing press - Google Patents

Description

Malfch 14, 1933. F, CARLSQN 1,901,284

PRINTING PRESS Filed Feb. 12, 1932 INVENTOR BY a flip A'ITORNEY IMlarkozz.

Patented Mar. 14, 1933 FRANK r. chanson, or ASTORIA, new Yon-K rrtm 'rrne rnnss Application filed February 12, 1932. Serial No. 592,459.

This invention relates to printing presses in general, and particularly to improve ments in the construction of the inking arrangement ofsuch presses.

The prime object of my'invention is to provide an improved inking process for printing presses, wherebyink will be evenly distributed over their forms, nomatter in which direction the latter are operated.

Another object of my invention is to. provide suitable 1neans,.whereby such improved inking process will become effectively operatable. g

Before commencing with a detailed description of the invention itself, it may be well to explain the same in general principle and make suitable comparisons with present day methods.

It is well established that an inking roller supplies ink best to the'form during. the contact with the latter for the period of its first revolution, i. e., during the period its total circumferential ink supply is transferred to the form. During itssecond revolution in contact with the form the inking quality of the roller will become less, and will further diminish during subsequent revolutions of the roller, while in contact with the form. r v

Although this fact applies to presses of any type, I have particularly in mind what is known as the fiat-bedcylinderpresses, which are especialy known for their poor inking qualities at the front and at the rear ends of their forms, depending upon the arrangement of their inking rollers, which may contain one or a plurality of individual roller units. In printing from large'forms in such presses, the print at either end, or at both ends will not only appear considerably lighter than in themiddle portion but will show the so-calle'd back-lash, of the gears (by means of which the feed rollers are operatively connected), and it will be also observed that the sideplay of the inking rollers will become readily evident in the print, due to the fact that these rollers are loosely lodged in their bearings and follow a. reciprocating motion imparted to them by the so-called vibrator. The latter consists of a steel roller which reclprocates While revolving, and imparts these combined motions to the inking rollers. The marking-of this sideplay, reproduced upon the printed subject, will be discern" while applying the rollers, by. reverting them to their contacting position with the form, when the latter moves in opposite direction. However, all these developments ibleto a greater or lesser extent, according are depending entirely upon the operation and movement of the press-beds, or upon the movement: of the roller frames, in what is known as job printing presses. In all cases the operation of the rollers is accomplishedby, either a cam, eccentric or similar positive mechanical motion in conjunction withthe movement of the bed or other parts of the press. While these arrangements provide somewhat improved inking of the form, they still have important defects in that they do not overcome the marking on n the printof the gear back-lash and of the reciprocating motion of the. roller. Such defects are not so noticeable in job presses, but are decidedly distinguishable in flat-bed presses and are mainly due to the fact, that the surface speed of the roller is different from that of the form, when the roller is brought intocontact with the latter, after having been temporarily removed therefrom. y 7 The present invention employs an entirely different method, whereby all the aforesaid defects of heretofore designed inking roller arrangements are not only eliminated, but which has the additional advantage of applying to the endsof the form, already normally inked, a; fresh supply of ink which is undisturbed and therefore remains well distributed on the inking roller, thereby assuring printing from an entire uniformly inked surface of the form.

This method, and the means for accomplishing it, will become more fully evident from the following description in connection with the accompanying drawing. The latter are intended to illustrate the operation of the method in connection with existing flat-bed cylinder presses, but are by no means intended to limit my disclosure to the actual showing, as they serve merely for explanatory purposes, and in which Fig. 1 is a diagrammatical arrangement, illustrating a series of inking rollers, the last one of which is in frictional engagement with a vibrator or steel drum.

Fig. 2 illustrates a similar arrangement where a small steel vibrator is employed.

Fig. Sis a diagrammatical cross-sectional view of a preferred form of a bearing employed in my improved printing process, and

Fig. 4 is a top view of a modified form of a bearing.

Referring to the drawing, numeral 10 denotes the form of a flatbed printing press, over which is disposed asteel drum or vibrator 11 in frictional contact with an inking roller 12, preferably made of highly elastic composition. Adjacent to roller 12 are other'rollers 1.3 and 14, which are permanently lodged in fixed plain bearings 15, open at the top. Roller 12 is lodged also in a fixed bearing indicated at 16, which, however, has provisions for seatin the shaft 17 of the roller in two different positions during the movements of thebed. The lower position of shaft 17 is defined through the low bearing surface marked 18, and isheld in elevated position by an upper bearing arrangement 19. While in its lower position, roller 12 will contact with form 10, and in its upper position the roller will be removed above the-form. r

The shifting of the roller from its lower position to its upper position and from its upper position to its lower position is not caused by any specific mechanical means, as mentioned in connection with previously employed devices of similar nature, but is entirely caused through the frictional engagement between steel drum 11 and roller 12.

Operation When form 10 moves in the direction of arrow I, drumll is moved in anti-clockwise direction, indicated by I, and roller 12, indicated in full lines, is caused to rotate in clockwise direction indicated by arrow 1. The surface speed of both the form and roller 12 remains always identical, since the roller is free to revolve.

When the form moves in opposite direction, marked II, roller 12 is caused to rotate tirely eliminated.

supplied to roller 12 willv not only be genin anti-clockwise direction II", and drum 11 is rotated in clockwise direction indicated by II. 7

Due to the arrangement of bearing 16, and the frictional engagement between drum 11 and resilient composition roller 12, the latter will be caused to become elevated to its dotted line position above the form and will receive during several of its revolutions, while free from the form, a generous sup ply of ink. During this period, the form moves in direction IIfwit-hout being touched by roller 12. Because of the fact that roller 12 is free to rotate in contactwith vibrator 11, the surface speeds of vibrator and roller will be identical. Due to this. uniformsurface speed of both cylinders, the usual streaks appearing on the. inking roller,

caLsed by the reciprocation of the vibrator,

and the back-lash of the gears, will be en- In this manner, theink erous, but also. uniformly. distributed.

NVhen now the form moves in the opposite direction, the direction of the drum is simultaneously reversed. Due to the fact that'roller' 12 was elevated above the form, and the vibrator or drum 11' maintains its surface speed corresponding to that of the form, the surface speed'of roller 12 will be equal to that of the latter. The reversal of the form is simultaneous with the reversalof the direction of rotation of both the drum and roller 12, and the latter returns quickly, due to the reversed rotation of drum 11, into contact with the form, while the surface speed of roller 16 conforms to that of the form. This repositioning of roller 12 is practically immediate, and is again caused by the frictional engagement of drum 11 with the roller.

Since there are no reversal stops of the drum and roller 12 while the latter is in contact with the form, but on the contrary, because such stops occur while roller 12 is free from the latter, streaks or shadows which may in heretofore used devices bereproduced by the roller coming in contact with the form,'are entirely overcome through the provision of permitting roller 12 to rotate freely, while being propelled by the drum.

Thus the roller will spin around several times prior to its contact with the form, whereby the ink upon the roller is thoroughly and evenly distributed, and in this well distributed state the ink is then delivered to the form by the roller, while the surface speeds of the latter and the form are equal.

The same operation applies to an arrangement shown in Figure 2, where again a form 201is illustrated in contact with an inking roller 21, which latter is lodged in a fixed open bearing 22. Adjacent to when 21,

there is seen another composition roller 23,

which is .lodgedin a bearing 24 arranged A in similar manner as that indicated at 16 in Figure 1, and having a lower bearing surface and an upper bearing surface 26, for accommodating shaft 27 of roller 23.

' In contact with both rollers there will be seena small steel vibrator 28. When form 20 moves in the direction I, vibrator 28 moves in direction I and causes, through frictional engagement with roller 23, to elevate the latter into bearing position 26, thus causing the roller to leave form 20 and to assume its dotted-line position. In this position the vibrator supplies the roller during several of the latters revolutions with fresh ink and evenly distributes it over the roller.

When the form is caused to move in opposite direction, indicated at II, vibrator 28 is also rotated in opposite direction II and causes the elevated roller 23 to revert to its full line position and into contact with the form. r

The same advantages of uniformly distributed ink over the roller and-streakless transmission of the ink to the form, coupled with a generous supply of ink to the end portion-of the form, which ordinarily would receive the least ink supply, completes the desired effect of uniform ink distribution over the entire form surface, resulting into a uniformly printed job without shadows or streaks. a

In order to preclude the possibility of involuntary or undesired movement of inking rollers 16 or 28, relative to the form or to the vibrator, my double bearing may be equipped with yieldable detent means, intended to hold the roller shafts in their proper position, either in their upper or their lower bearing seats, or prevent the rollers from vibrating, when encountering slight unevenesses of the form, as the latter passes under the rollers. Such provisions are shown in Figure 3. There will be seen a bearing arrangement 29, again provided with a lower bearing portion 30 and an upper bearing portion 31, the latter equipped with the usual well 32 for receiving lubricating matter. In the intersection between upper and lower bearing portions there will be observed a spring propelled ball 33 intended to operate as a detent forthe shaft of the roller, when in either upper or lower position.

In Figure 4 there will be observed a sim- 1 ilar bearing arrangement, in which, however, ball 33 is replaced by a roller 34, also preferably propelled by a spring, not shown; in this modification the contact line between shaft and detent is far greater than in the ball construction.

From Figures 1 and 2 the specific arrangement of the two shaft bearing surfaces will be clearlyunderstood. The device will operate correctly only, when the a centre line of one bearing portion is parallel with the: centre line of the other bearing portion, and when the centre lines of both bearing sections form points of a common circle, the centre of which coincides with the centre line of the vibrator. To effectively elevate and lower the roller, the centre lines of the two bearing surfaces must lay in different horizontal planes.

While I have shown a specific bearing arrangement with a double seat for the roller shaft, and the provisions for holding the shaft in either upper or lower position, and

particularly in the latter position, for preventing its dislodgement by uneveness of the form, be it understood that any other suitable means for accomplishing the same results, may be devised, as long as the principal ideas and results of my new method are accomplished.

hese results may bebriefiy stated as follows: I i

1. Prevention of insuflicient inking of the ends of large forms. 7

'2. Preventing shadows in the print.

3. Preventing the demarka-tionfor indication of the backlash of the gears.

4. Preventing the visibility on the print, ofmarks caused by the side-play of the roller induced by the vibrator.

5. Providing a fresh supply of ink, unencumbered by any the end portions of the form.

6. A correct and thorough distribution of the ink over the roller, due to the latters receiving several additional revolutions, while removed from the form. t

7. Assuring at all times the identical surface speed of the steel roller and the ink roller relative to the speed of the form, and

8. Assuring the quickest possible return of the roller to the form, while the surface 95. part of the-press, to V speed of the roller and the Vibrator is maintained equal to the surface speed of the .tween vibrator and inking roller, for promoting the shifting of the latter from or against the form. And while I have explained and shown specificarrangements, be it understood that changes and improvements may be incorporated to further refine my'invention, and therefore, reserve for myself the right to make such changes and improvements without departing from the broad scope of my idea, as set forth in the annexed claims.

. I claim:

1. A printing press having an inking roller permanently in frictional engage ment with the vibrator, adapted to be alternately elevated above and lowered into contact with the press-form through the alternate changes in rotation of said vibrator.

2.- A printing press having a metal vibrator and a highly resilient inking roller permanently in frictional engagement with the vibrator, the latter adapted to cause, through its alternate change in rotation, the alternate elevation of the roller above, and its lowering into contact with the form of the press. 3. A printing press having a steel vibrator and a highly resilient inking roller in permanent frictional engagement with said vibrator, said roller adapted to change its position relative to the form of the press, said vibrator adapted to elevate said roller above the form, when rotating in one direction (while the form moves in a corresponding direction), and to lower said roller into contact with the form, When rotating in opposite direction (While the form moves in a direction, corresponding to the reverse rotation of the vibrator), said roller further adapted to come in contact with the form at a surface speed equalling that of the form.

4. In a printing press, including a reciprocating form, inking rollers and vibrators, one or more of said rollers being in constant frictional engagement with said vibrators and adapted to be alternately elevated above and lowered into contact with the form, depending upon the change of direction in the movement of the latter, such elevation and lowering of the roller or rollers being caused by the alternate reversal of rotation of the vibrator, corresponding to the change of direction in the movement of the form.

5. In a printing press, including a reciprocating form, a plurality of inking rollers, and a vibrator; an inking roller made of highly resilient material in constant frictional engagement With said vibrator, bearing means provided for said roller, adapted to facilitate an alternate positioning of the latter above, or in contact with the form, When rotated by the vibrator alternately first in one and then in opposite direction.

In testimony whereof he affixes his signature.

FRANK P. OARLSON.

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