US1883638A - Multicolor intaglio printing machine - Google Patents

Description

Oct. 18, 1932. A. A. EGLI MULTICOLOR INTAGLIO PRINTING MACHINE Filed Sept. 22, 1928 2 Sheets-Sheet l Oct..18, 1932. A. A. EGLI MULTICOLOR INTAGLIOLPRINTING momma Filed Sept. 22, 1928 2 Sheets-Sheet 2 r m m. V m

Patented Oct. 18, 1932 UNITED STATES.

PATENT OFFICE ARNOLD AUGUST EGLI, OF HAMBURG, GERMANY IULTICOLOB INTAGLIO PRINTING MACHINE Application filed September 22, 1923, Serial No.

self shaken owing to another printing cylinder beginnin to print later; this shakin cannot be avgided, however heavy the bear ings of the impression cylinder maybe, because the elasticity of the body of the impression cylinder itself allows some vibration to occur to an extent which gives rise to the diiliculties hereinafter described. The print consists in fact of microscopically small so points and The slightest vibration causes the dimensions of these points and lines to be-altered, so that a print which is diflerent from that intended is produced, and in particular light and dark strips of shading are formed so that the value' of the print isreduced. As is known these appearances of shading are called tooth-strips. in mechanical book presses, ofiset and lithographic printin machines, because they occur in these machines owing to the shaking caused by the engagement of the teeth. The present invention overcomes all these difliculties of the known arrangements, by arranging the printing cylinders in such a manner that the printing cylinders which print conjointly, are

brought into action simultaneously.

Preferably the arrangement is such that the printing cylinders are brought into position for printing-before the actual print ing takes place; that is to say, they are brought into position on the free edge of he print which remain unprinted, so that a l shaking during the actual printing is entirely avoided. In the case of three color sheet intaglio printing machines preferably the first and third printing cylinders each begin to print on an impression surface simultaneously, while the second printing cylinder which is preferably arranged between them prints by itself. In four-color sheet 307,780, and in Germany Septembcr'26, 1927.

intaglio printing the first and third printing cylinders begin to print simultaneously each on an impression surface as do also the second and fourth, and in this case the second printing cylinder is advantageously arranged between the first and third printing cylinders; the printing by the second and fourth printing cylinders then takesplace after or before the printing by the first and third printing cylinders. 0 According to a further development of the invention the printing cylinder system is so arranged relatively to the impression cylinder that the center of the printing cylinder system lies approximately in or somewhat below the horizontal plane containing the axis of the impression cylinder. By this means a position of the printing-cylinder system is obtained whereby the path which the coloring fluid has to travel on the printing cylinder from the inking roller until it is applied, is relatively short, so that evaporation is 'reduced to a permissible degree. If the position of the printing cylinder is still lower the paths of thecoloring fluid are further shortened, but the lowest printing cylinder in such case is situated in a position in which it is e not accessible. On the other hand, if the printing cylinder systemis raised so that its centre lies above the horizontal plane through the axis of the impression cylinder, the paths of the color during which evaporation takes place arelengthened to an extent which impairs the quality of the work.

Two embodiments of the invention, namely a threeand four-color sheet intaglio printing machine, are illustrated by way of example in the accompanying drawing in which Fig. l-is a diagrammatic illustration of the arrangement of the printing cylinders in a three-color sheet intaglio printing machine,

Fig. 2a diagrammatic illustration-of the. arrangement of the printing cylinders in a four color sheet intaglio printing machine again in accordance with the invention, and

3 is a diagrammatic view showing the machine in greater detail and illustrating the operating mechanism for the printing 100 cylinders, the view being taken from the rear of Fi 1.

Referring to Fig. 1 of the drawing, the impression cylinder (1 has four impression surfaces 6 b b and 6 The beginning of each impression surface is displaced by an angle of 90 from the beginning of the next surface. According to the invention, the three printing cylinders 0 c and 0 the axes of which lie on an imaginary cylindrical surface concentric with the axis of the impression cylinder, are arranged in such a manner that the centres of the printing cylinders c and 0 lie on the arms of a quadrant of 90, the apex of which coincides with the centre of the impression cylinder at. The arrangement is therefore such, that the printing cylinders 0 and c always face corresponding portions of two of the im ression surfaces 6 to 6 and these two printing cylinders are caused to move simultaneously toward the impression cylinder by means of any suitable mechanism and engage such cylinder at the same time, while the cylinder 0 is separately brought to printing position and prints by itself. l

I have found that particularly in a printing apparatus of such kind that the cylinders c and 0 are moved into printing position before the printing begins i. e. to the free edge of the sheet which remains unprinted, the unavoidable shaking of the impression cylinder cremains without effect. During the printing by the printing cylinders 0 and 0 no further shaking of the impression cylinder takes place. Only when the beginning of the impression surface 6 is located by the printing cylinder 0 does this cylinder begin to print, without the shaking which is caused thereby doing any harm because the printing cylinder 0 prints by itself.

In Fig. 2 the impression cylinder A has five impression surfaces B B B B and 13,, the beginning of each of which is displaced by ,an angle of g =72 from the next. According to the invention the four printing cylinders C C C and C the axes of Which lie along a cylindrical surface concentric with the axis of the impression cylinder, are so arranged that the centers of the printing cylinders C and C or of C and C each lie on an arm or radius of a sector of 72 the apex of which coincides with the center of the impression cylinder A. The printing cylinder C lies between the printing cylinders C and C The cylinders C and C thus simultaneously engage the printing fields B and B and whenthey have finished their printing they are withdrawn; as

soon as the advance edges of printing fields B and B reach a position opposite the printing cylinders C and C respectively, these latter cylinders are simultaneously moved ,into printing position. Thus, no printing cylinder is moved into printing position while another cylinder is printing, and consequently no jarring or vibration occurs while any cylinder prints.

I have found that, particularly in a printing apparatus of the kind such that the cylinders G and C or C and C are closed up before printing i. e. on to the free edge of the sheet which remains unprinted, the unavoidable shaking of the impression cylinder A remains entirely Without effect. During printing by the printing cylinders C and C no furthershaking of the impression cylinder A takes place. Only when the beginning of the impression surface B is located in front of the printing cylinder C and the begin ning of the impression surface B in front of the printing cylinder C are the printing cylinders C and C closed up simultaneously,

system is somewhat below the horizontal plane through the axis of the impression cylinder. In this way an arrangement of the system of printing cylinders is obtained whereby the paths of the coloring fluid on the printing cylinders from the inking rollers to the line of contact with the impression cyl inder are short, so that the color evaporates only slightly. By lowering the position of the printing cylinders the paths can be further shortened but the lowest printing cylin-- der is then in'an inaccessible position. If the printing cylinder system is raised so that its center lies above the horizontal plane containing the axis of the impression cylinder. the paths of the coloring fluid on the printing cylinder where evaporation occurs are lengthened so that the colors arrive at the place of application in a condition in which they have already begun to dry, with the re-. sultthat a satisfactory print is not obtained. I have found that optimum conditions prevail when the center of theimpression cylinder, the center of the lowestof the three printing cylinders and the center of the inking roller belonging to such lowest printing cylinder all lie in a straight line or nearly so, so that the shortest path for the coloring fluid on the printing cylinder from the inking roller to the point of application on the impression cylinder is provided, without bring ing the lowest printing cylinder into an inaccessible position. v

Fig. 3 shows diagrammatically the mechanism for operating the printing cylinders 0 0 0 the scrapers of the printing cylinders being indicated by the characters d d 03 The color troughs are shown at f f f while the color rollers are indicated by the letters 6 e a The printing cylinders and their scrapers, color troughs and color rollers are mounted upon lateral carrying frames k k k which are rotatably mounted in the frame Z of the machine, as shown at g g 9 respectively. 1

The printing cylinders are moved toward and away from the impression cylinder at in the following manner. The printing cylinders c 0 or their drives are so coupledthat they begin to print, simultaneously. A guide 10 engages the pivot 2' of the frame b such guide being articulated to the crank Z as shown at m The crank is formed by one arm of a two-armed lever Z Z which is pivoted at m. The arm Z is connected with the arm L, of the double lever Z Z by the coupling rod 0 The arm Z5 is connected'with an oscillating lever 9 a by a coupling rod 12 a such lever being joined through its other end with a link 13 which is-in turn connected wlth a sharp-angled lever 8 The latter is pivoted in the frame of the machine at t; itsfree arm carries a roller '0 a which bears against the cam u. Through the mechanism just described the cam u controls the double levers Z Z and Z Z The oscillating movement of these double levers is transmitted to the frames k and k through the guides k and k and through such frames to the printmachine frame.

lever being rotatably mounted at 11. in the frame Z of the machine. The arm Z is connected through a coupling rod o 'with a double lever p which is pivoted at g in the The other arm of-sucli lever is controlled through a rod 7- by adouble lever 8 rotatably mounted at in the machine frame. The horizontal arm of this double lever is connected by a link '0 with a bell-crank lever :0 at 'w the latter lever being oscillatable about the axis g The free arm'of lever m carries a roller 2 which engages the cam u. The cam is rotated by a shaft W which is geared to the driving motor of the machine. The arrangement of the printing cylinders and cam is such that the novel operations above described, namely,

the simultaneous beginning of printing of machine, the combination of an impressionthe cylinders which tained.

I claim:

1. In a multi-color sheet intaglio printing print together, are obcylinder having more than two printing surfaces thereon, more than two printing cylinders whose axes lie upon an imaginary cylinder concentric with the axis of the impression cylinder, mechanism operative upon at least two, but'less than all, of said printing cylinders to move the same simultaneously against different printing surfaces while the other printing cylinder or cylinders are in non-- on, three printing cylinders whose axes lie upon an imaginary cylinder concentricwith the axis of the impression cylinder, mecha nism operative upon two of the printing cyl inders to move the same simultaneously against different printing surfaces while the third-printing cylinder is in non-printing position, and means for moving said third printing cylinder toward said impression cylinder after the two first-mentioned cylinders have finished printing, whereby the disturbing effect of vibration is eliminated.

3. In a three color sheet intaglio printing machine, the combination of an impression cylinder having four printing surfaces thereon, three printing cylinders whose axes lie upon an imaginary cylinder concentric with the axis of the impression cylinder, mechanism operative upon two of the printing'cylinders to move the same simultaneously against 'dilferent printing surfaces while the third printing cylinder is in non-printing position, and means for moving said third printing cylinder toward said impression cylinder after the two first-mentioned cylinders have finished printing, whereby the disturbing effect of vibration is eliminated, the third printing cylinder being arranged between the two first-mentioned printing cylinders.

4. The combination as set forth in claim 1, wherein the center of the printing cylinder system lies in or below the horizontal plane passing through the axis of the impression cylinder.

5. The combination as set forth in claim 2, including inking rollers associated with said printing cylinders, the centers of the axes of the impression cylinder, the lowest printing cylinder and its associated inking roller lying along a straight or an approximately straight line.

In testimony whereof I have hereunto set my hand.

ARNOLD AUGUST EGLI.

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