US1954851A

US1954851A - Printing machine

Info

Publication number: US1954851A
Application number: US570542A
Authority: US
Inventors: John F Springstead
Original assignee: R Hoe and Co Inc
Current assignee: R Hoe and Co Inc
Priority date: 1931-10-23
Filing date: 1931-10-23
Publication date: 1934-04-17
Anticipated expiration: 1951-04-17

Description

A ril 17, 1934. J. F. SPRINGSTEAD PRINTING MACHINE INVENTOR: 31%

Patented Apr. 17, 1934 V UNITED STATES FATE FFm

PRINTING MACHINE pany, receiver Application October 23, 1931, Serial No. 570,542

6 Claims.

My invention relates to printing machines, and more particularly to that class of printing machines which are adapted to print according to the rotary photcgravure method.

Printing machines of the kind referred to usually comprise a form cylinder having a copper surface on which the matter to be printed is etched, the cylinder being mounted to rotate in an ink fountain underneath the same, and having adjustably located near the upper part of the cylinder a doctor blade which removes surplus ink. The paper is led from a web roll and passes over the form cylinder, but according to the present practice touches the same only momentarily and at a very small portion of its periphery. It has been found that such a momentary impression, while the same may be efficient with regard to ordinary printing, does not produce satisfactory results in practicing the rotary photogravure art.

It is therefore one of the principal objects of my invention to provide means whereby the paper, on being led from the web roll, is held in contact with the rotating form cylinder for an appreciable time, that is to say, the portion of the periphery of the form cylinder with which the paper comes into contact is quite substantially increased.

Further objects and advantages of the invention will be in part set forth in the following specification and in part will be obvious therefrom without being specifically pointed out, the same being realized and attained by means of the instrumentalities and structural characteristics and relative arrangements and combinations which will be hereinafter more fully described or which will be pointed out in the claims hereof.

With the above and other objects of the invention in view, the invention consists in the novel construction, arrangement and combination of various devices, elements and parts, as set forth in the claims hereof, one embodiment of the same being illustrated in the accompanying drawing and described in this specification.

In the accompanying drawing,

Figure l is a side elevation of a portion of a printing machine embodying my invention, and

Fig. 2 is a detail view taken at right angles to Fig. 1, as indicated at the left-hand side of Fig. l by the arrow marked 2.

In carrying my invention into efi'ect, in the embodiment thereof which has been selected for illustration in the accompanying drawing and for description in this specification, I provide a shown in the drawing) over the roll G, under the roll H and over to the form cylinder A, passing between the same and the impression cylinder B. The paper passes over the form cylinder for a substantial distance, and under the auxiliary impression roller K, then upward and over the roller L and up to the heated drum D, passing nearly entirely around the same and down to the guide roll M, and away from this part of the machine, as indicated at N. An ink fountain J is located below the form cylinder A, the lower part of which dips into the fountain and receives ink, the surplus of which is removed, as the formcylinder rotates in a counterclockwise direction, by the doctor blade C.

The auxiliary impression roller K is shown in the drawing as adjustably pressed against the form cylinder A, and this is the preferable construction, but this auxiliary roller K need not be adjusted so as to actually press the paper against the form cylinder, but may be, if desired, spaced away from the form cylinder, though still maintaining a substantial arc of contact of the web with the form cylinder.

The auxiliary impression roller K is borne at the lower end of an arm 0 which is pivotally secured to the frame of the machine at P. The

angular relation of the arm 0 to the frame of,

the machine is regulated by the screw Q, which acts upon a short arm R, in a manner which will be Well understood.

The longitudinal adjustment of the roller K is controlled by the spring S and the lock-nut T, in a manner which will be clear from the drawing and requires no detailed explanation. As explained above, while it is preferable to so arrange the auxiliary roller K that it presses the web against the form cylinder, it may be desirable that the roller be slightly spaced away from the form cylinder, and the adjusting means just described permit such an adjustment to be made.

The operation of my invention will be clear from what has been already said with regard to its construction.

The advantages of the invention consist principally in the fact that the same provides an efficient and easily installed and operated adjustable means of securing the contact of the paper with the form cylinder A over a greater space than has been practicable in printing machines as used in the prior art. By thus hold-- ing the paper in contact with the form cylinder for a greater period of time, it has been found that a greater amount of ink is drawn from the form cylinder to the paper, thus producing greater depth of printing. In rotary photogravure printing machines as ordinarily arranged in which the paper makes only a line of contact with the form cylinder, a considerable amount of ink is usually left in the etched portions of the cylinder after the contact with the paper, but by carrying the web along in contact with the cylinder in accordance with my invention, the paper will take up a considerably greater amount, or practically all, of the ink from the etched portions of the cylinder, which greatly increases the depth or contrast in the printed picture.

I do not limit myself to the: particular details of construction set forth in the foregoing specification and illustrated in the accompanying drawing, as the same refer to and set forth only one embodiment of the invention and it is obvious that the same may be modified, within the scope of the appended claims, without departing from the spirit and scope of the invention.

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

1. In a rotary photogravure printing machine, the following elements in combination: a supporting frame, a form cylinder, a main impression cylinder, and an auxiliary impression roller resiliently mounted and adapted to hold a web of paper in contact with an arc of the periphery of the form cylinder beyond the point of engagement of said form cylinder and said main impression cylinder, said auxiliary impression roller being swingable angularly over the periphery of the form cylinder.

2. A'rotary photogravure printing machine as set forth in claim 1, characterized by the fact that the auxiliary impression roller is connected to means adjustably and pivotally secured to the frame of the machine so that said impression roller may swing angularly over the periphery of the form cylinder while maintaining said web of paper thereagainst.

3. A rotary photogravure printing machine as set forth in claim 1, characterized by the fact that the auxiliary impression roller is connected to means adjustably mounted on said frame so that said roller may be adjusted angularly over the periphery of and toward or away from the form cylinder.

4. A rotary photogravure printing machine of the character described comprising in combination a supporting frame, a form cylinder, a main impression cylinder, an auxiliary impression roller engageable with a web for maintaining same in contact with an arc of the periphery of the form cylinder beyond the point of engagement of said form cylinder, said auxiliary impression roller being yieldingly and adj ustably mounted in means secured to said supporting frame, said means being angularly movable over the periphery of the form cylinder and manually adjustable relatively to the supporting frame for varying the length of the said are of the periphery.

5. In a rotary photogravure printing machine, the combination of a supporting frame, a form cylinder, a main impression cylinder, and an auxiliary impression roller adapted to hold a web in-contact with an arc of the periphery of the form cylinder beyond the point of its engagement with the impression cylinder, said auxiliary impression roller being reciprocatingly movable relatively to means securing same to said frame and angularly movable over the periphery of the form cylinder while maintaining contact of the said Web with the form cylinder.

6. A rotary photogravure printing machine of the character described comprising in combination, a supporting frame, a form cylinder, a main impression cylinder, an auxiliary impression roller engageable with a Web for maintaining same in contact with an arc of the periphery of the form cylinder beyond the point of engagement of said form cylinder and said main impression cylinder, said auxiliary impression roller being secured to means mounted on said supporting frame, said means being manually adjustable relatively to the supporting frame for moving said auxiliary roller angularly over and towards or away from the form cylinder, and thereby varying the effective length of the said are of the periphery, said auxiliary impression roller being resiliently pressed into contact with said web by spring mechanism, said spring mechanism being secured within said means, and other means within said member for varying the tension of said spring mechanism whereby the auxiliary impression roller may force the web with a variable pressure against the form cylinder.

JOHN F. SPRINGSTEAD.