US2126768A - Dampening system for lithographic and analogous presses - Google Patents

Description

Aug. 16, 1938. J. G. GOEDIKE 2,126,768'

I DAMPENNG SYSTEM FQR LITHOGRAPHIC AND ANALOGOUS PRESSES Fi'led Jan. 20,' 1938 dbh/1 G. Goed/z' Ke HTTQRNEY Patented Aug. 16, 1938 UNiTED STATES. PATENT OFFICE 1 masses ANALOGOUS PRESSES John G. Goedike, San'Antonio, Tex. Appllcltlon Jilllll'! 20, 193s, Seal N0;v 185,812

8 Clim. (Cl. lol-147) `4 remmendeths m if March a, rasa as amended April so, 192s; 37o o. erm) This invention described herein may be manul factured and used by or for. the Government for governmental purposeawithoutthe payment to me of any royalty thereon.

5 rI his invention relates generally to the art of lithography and particularlyto the dampening of the printing surface of lithographie and analogous presses. l

One of the objects of the invention is to provide -10"a uid interface dampening system for dampenin g the printing surface of lithographie and analogous `presses whereby true surfaced rubber or composition dampening rollers may be used against the printing surface.

" Another object of the invention is to provide wicks in the form of endless loops or belts for supplying a dampening fluid by capillary action from a source of fluid supply to a dampening fluid carrying roller included in a fluid interface vsystem for dampeningthe printing surface of lithographie and analogous presses whereby flexlble loop portions may be formed on thel wicks for contacting with the dampening roller to maintain a continuous feed of dampening fluid from .25 the source of supplyto the roller from above and below the point of contact of the loop portions of the wicks, without appreciable wearing or fraying at the line of contact oi' the loop portions with the dampening roller and permitting the use of any section of the endless wicks forforming the loop' portions thereon.

Another object of the invention is to provide a system, vfor dampeningthe printing surface of lithographic and analogousv printing presses,

which comprises a dampening fluid carrying roller, a source of dampening fluid supply. means for transmitting the dampening fluid from said sup- V4:so faces of llithographie and analogous printing presses it has been considered necessary to make the printing surface dampeningrollers of cotton fabric due-to the fact that the feed for the dampening fluid was accomplished by a ductor roller composed of an absorbent material and the printing surface dampening rollers being composed. of an absorbent material they could not be molded and trued for maintaining an even pressure on the printing surface through their full length,

when aligned and set in contact with the printing 5 ning against the printing surface of the press and these composition dampening rollers may be of an absorbent or non-absorbent material.

With the above and other objects and ad- '-3 vantages in View, the invention consists of certain features of construction and arrangement of parts which will hereinafter appear. y

For purposes of illustration the invention will 'be claimed with reference tothe accompanying drawing in which like members distinguish like Parts and in which- Fig. 1 is a side elevation partly in section of a printing press embodying the invention, and

Fig. 2 is a fragmentary perspective view part- 25 ly in section thereof.

In the illustrative embodiment characterizing the invention, I indicates a plate cylinder of a lithographie or analogous press containing the design 2 to be printed, which is dampened by roll- 30 ers 3 in contact therewith. The lrollers 3 may be composed of rubber or similar composition Whereby they may be molded and trued so that when aligned and set in contact with the plate cylinder i an even pressure is possible through their full 35 length. These dampening rollers, however, in this system may be made of an absorbent or nonabsorbent materiali 'I'he dampening rollers 3 also contact with a non-absorbent dampening a fluid carrying roller 4', which is supplied with 40 dampening fluid bj means of aplurality of wicks 5 that are supported on a plate 6 contained withf in a'tr'ough 1, having a supply of dampening fluid 8 provided therein. The wicks .5 are made of absorbent material in the form of endless loops or belts which are collapsed or closed upon themselves to lie nat on the supporting Plate 6 within the trough and are held in place thereon by a cover plate I.

The supporting and cover plates 6 and 9 re- 50 spectlvely'are provided with an inclined portion I0 for directing the inner ends of the wicks 5 upwardly from the trough 1, to contact with the `roller l and are of a shorter length than the wicks, whereby the inner and outer'ends of the wicks-.|55

may extend outwardly from both ends of the plates. l

By forming the wicks in the shape of endless loops or belts, loop portions Il and I2 may be formed on any portion of vthe endless loops or belts, and an upper and lower layer Il and I4 respectively provided thereon, which gives the eifect of two layers of wick for feeding the dampening fluid from the trough by capiliary action and at the point of contact I5 of the loop portions Il with the roller 4 the dampening fluid is coming from two directions in the loop Aportions. The elasticity of the loop portions II causes a light contact with the surface of the roller 4, thereby permitting the wicks to continue in service for a considerable period without fraying or fouling, and as the wicks are in the form of endless belts they are easily moved to permit the use of any section of the wicks for forming the loop portions in case they become fouled with ink, which may accumulate on the surface of the roller 4.

While the dampening fluid carrying roller 4 is rapidly rotating a constant stream I l of the dampening fluid is maintained from the line of contact ofeach wick band l on the surface of the roller 4, to the line of surface contact of a nonabsorbent dampening iluid control roller I1, with which the roller 4 is in close contact. The stream It of the dampening fluid from each wick spreads to form a head Il of dampening fluid at the line of surface contact Il of the rollers 4 and I1. At the line of surface contact Il of the rollers 4 and I1, the head I l of the dampending fluid is constant while the rollers rotate. Due to capilllary `action and rotational force of the rollers 4 and I1, a spreading effect results in a lLmiform film across these rollers. 'I'he amount of dampening fluid necessary for the operation of the press is correctly metered from the head Il of dampening fluid bbthe contact pressure of the rollers 4 and I1 with each other and is carried by the roller 4 to the surface contact of the plate dampening rollers I where it again as an interface, and an even illm ofthe dampening fluid is carried on the surfaces of the plate dampening rollers l to the surface contact 2l of these rollers with the surface of the plate cylinder I. A water interface is constant at the surface contact of each plate dampening miler I and plate cylinder I, and as they revolve in the direction as indicated by the arrows a film of dampening fluid which is even and unchanging is carried away on the surface of each.

In this system the dampening fluid carrying roller 4 andthe dampe ng fluid control roller I1 are aligned horizontal and rotate'in the direction of the arrows in contact with each other and must be of non-absorbent material so that where the surfaces of these rollers contact a dam is formed at the head Il of the dampening fluid. The rotational force of the rapidly rotating rollers 4 and i1 draws the dampening fluid from thel head Il thereof and forces it to'pass the surface contact Ilof4 the rollers as an interface, regardless of the close contact of the rollers. This is due to the interfacial surface tension of the dampening fluid interface, which will withstand greater pressure than will ever exist between the rollers of a system of this kind. When this fluid interface vdampening system'is used with This coating is obtained by simply touching the surface of any one of the rollers with a slight amount of the substance and permitting the rollers to rotate a few revolutions .before the actual press operation is started.

It -will thus be seen that there is provided a highly no vel and useful fluid interface system for dampening the printing surfaces of lithographie and analogous presses. Even though there has been herein shown and described certain features of construction and*V operation of parts, it. is nevertheless tol be understood that various changes may be made therein without departing from the spirit or scope of the invention, such as supplying the dampening fluid to the system by other means than illustrated, as it is possible to supply the dampening fluid thereto by drip or spray.

Having described my invention, whatI claim as new and wish` to secure by Letter Patent is:

l. The method of dampening printing surfaces of lithographie and analogous printing members, which consists in feeding a dampening fluid from a source of supply in two directions through an endless path to a dampening system, and transmitting said dampening iluid to said printing surface through said dampening system.

2. The method of dampening printing surfaces of lithographic and analogous printing members,

dampening fluid to said member, said mechanism.l comprising a dampening system, including a source of dampening fluid and a plurality of collapsed endless wicks for feeding said dampening fluid from said source to said dampening system.

4..In a printing press, the combination with a printing member, mechanism for applying a dampening fluid to said member, said mechanism comprising a dampening system including a dampening fluid carrying roller, printing mem-` ber dampening rollers contacting with said printing member and said dampening iluid carrying roller, a dampening iluid control roller contacting with said dampening fluid carrying roller,

asource 'of dampening fluid and a plurality of collapsed endless wicks for feeding the dampening fluid from said source to said dampening fluid dampening 'system comprising a dampening fluidI carrying roller, dampening rollers contacting with said printing member and said dampening fluid carrying roller, a dampening fluid control roller contacting with said dampening fluid carrying roller, a source of dampening fluid, a plurality of collapsed endless wicks for feeding the dampening fluid from said source to said dampening fluidcarrying roller, and loop lportions.i'ormed on said wicks at the contacting portions thereof withv said dampening fluid carrying roller.

6. In a printing press, the combination with a printing member, a dampening system for applying a dampening fluid to said member, said dampening system comprising adampening fluid .said wicks at the contacting portions thereof with said dampening fluid carrying roller and support ing and .cover plates for said wicks mounted in said trough. l

7. In a printing press. the combination with a printing member, a dampening system for applying a dampening fluid to said member, said dampening system comprising a dampening fluid carrying roller, dampenin'g rollers contacting with said printing member, a dampening fluid control roller contacting with said dampenina fluid car- 'ri/ing roller, a trough, a sourcevof dampening Fluid provided in said trough, a supporting plate mounted in said trough, a pluralitylofcollapsed endless wicks mounted on said supporting plate for feeding the'dampening fluid from said trough to said dampening fluid carrying roller, loop por tions formed on said wicks at the contacting portions of said wicks with said dampening fluid carrying roller.v a cover plate mounted on said collapsed endless wicks and inclined portions on said supporting and cover plates for directing the said wicks from said trough to the said dampening iiuid carrying roller. said rollers of said dampening system including absorbent and nonabsorbent rollers.

8. 'The method of dampening printing surfaces of lithographie and analogous printing members consisting in' forming a loop oi' absorbent material, collapsing the loop. contacting one end of the collapsed loop with a distributing roller, irnmersing the greater part of the remaining porthe dampening fluid by capillary action through the ioopin two directions to the distributing roller, and transmitting the fluid on the distributing roller to said printing surface.

' JOHN G.

tion of the loop in a dampening fluid to convey v y

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