US2790385A - Cylinder mounting means for rotary sheet printing presses - Google Patents

Description

April 30, 1957 G. KALDscHMlD-r 2,790,335

CYLINDER MOUNTING MEANS FOR ROTARY SHEET PRINTING PRESSES, I

Filed May 14, 1953 3 Sheets-Sheet 1 pl'il 30, 1957 G. KALDscHMlDT 2,790,385 CYLINDER MOUNTING MEANS FOR ROTARY SHEET PRINTING PRESSES l Filed May 14, 1953 3 Sheets-Sheet 2 April 30, 1957 G. KALDscHMlDT 2,790,385

CYLINDER MOUNTING MEANS FOR ROTARY SHEET PRINTING PRESSES Filed may 14, 195s 3 Sheets-Sheet 3 INVENTOR.

United Sta-tes Parent' CYLINDER MOUNTING MEANS FOR ROTARY SHEET PRINTING PRESSES Georg Kaldschmidt, Dresden-Weisser-Hirsch, Germany, assignor to VEB Druckmaschinenwerk Victoria, VVB Polygraph, Heidenau, Saxony, Germany Application May 14, 1953, Serial No. 355,017

2 Claims. (Cl. 101-232) This invention relates to a rotary sheet printing press for letterpress work, particularly designed for printing on one side only, but adapted also for perfect yand multicolor printing.

In rotary printing presses provided with a plurality of printing mechanisms arranged one after another it is known to drive each of them individually from the main shaft extending horizontally along all these mechanisms.

The invention proposes a different arrangement the novel feature of which is that the printing mechanism as well as the delivery device of a rotary sheet printing press for letterpress work are each separately driven from the main shaft. Owing to this arrangement, the moving masses of the main driving members can be of lighter construction to insure steady running of the press as required for producing high-grade printing work. Furthermore, after releasing the fingers in case of incorrect feeding it is possible to throw oi impression by slightly swinging the impression cylinder away from the plate cylinder.

This swinging motion is known of course in presses, but in the known presses the printing cylinder driven together with the plate cylinder and the delivery drum by the same drive has to be lowered at least mm. to .throw olf impression, provided the plate cylinder with inking rollers set going and the delivery drum with its chains cooperate in a rolling motion. Considerable power is needed to overcome the friction developing for throwing off impression in this way.

These drawbacks are avoided by employing separate drives for the plate cylinders with impression cylinders and for the delivery drum. In the press according to the invention the entire throw-off mechanism operates easily, because the impression cylinder, without much expenditure of power, merely swings down toward the delivery drum. In a particularly advantageous constructional form of the invention the main shaft driven by a motor via a worm gear extends in vertical direction and, by way of a bevel gear system, separately drives the intermediate shafts for the delivery means, the printing mechanism and the inking apparatus if necessary.

All structural members may be kept small, since the stressing moments are small also.

On the shaft of the impression cylinder a stepped gear driven by the corresponding intermediate shaft is disposed with its angle of skew opposite to that of the driving gear of the impression cylinder. As the stepped gear is in mesh with the driving gear of the plate cylinder, axial thrust of the impression cylinder is eliminated.

Compared with known constructions, the printing mechanism drive according to the invention produces also a more elastic braking effect. This elasticity, however, cannot lower the quality of the print, since the plate cylinder is driven directly by the impression cylinder.

In the drawing,

Figure 1 is a diagrammatic side view of the main drive;

2,790,385 Patented Apr. 30, 1957 vCC 2 Fig. 2, a diagrammatic front View of the main drive with a view of the cylinders;

Fig. 3, a diagrammatic view of the customary way of throwing off the impression cylinder from the plate cylinder; and

Fig. 4 shows diagrammatically the throwing oi of the impression by causing the impression cylinder to beswung away from the plate cylinder according to the invention.

The rotary sheet printing press possesses a frame 1 for the reception of the inking apparatus 2, the printing mechanism 3 and the delivery means 4. The printing mechanism 3 includes the impression cylinder 5 and the plate cylinder 6 which is in contact with the rollers of the inking apparatus 2.

The sheets coming from the feeding device are guided by way of the feeding table 7 to the gauges 8 and are aligned by the lateral displacement means 9. After alignment a sheet is engaged by the gripping means 10 and delivered to the impression cylinder 5. In case of improper feeding the fingers 11 begin to act.

The printing mechanism 3 and the delivery means 4 are driven via the vertical main shaft 12, worm 13 and worm gear 14 by the motor 15 (Fig. l). On the main shaft 12 a spirally toothed bevel gear 16 is provided and in mesh with a spirally toothed bevel gear 18 keyed on the intermediate shaft 17 carrying a stepped gear 19 which by way of the stepped gears 20, 21 drives the delivery drum 22 (Fig. 2).

The main shaft 12 supports an additional spirally toothed bevel gear 23 which by way of a spirally toothed bevel gear 24 and stepped gears 25, 26 drives an intermediate shaft 27.

The impression cylinder 5 is driven by a pair of stepped gears 28, 29, arranged on the other side of the frame 1, through the intermediate shaft 27. The impression cylinder 5 is provided with a driving gear 30 in mesh with a spur gear 31 of the plate cylinder 6. The gears 29, 30 disposed on the shaft 32 of the impression cylinder 5 have an opposite angle of skew whereby axial thrust at the impression cylinder 5 is removed.

At the end of the main shaft 12 a bevel gear 33 (Fig. 1) meshes with a counter gear 35 on the intermediate shaft 34 which carries additional bevel gears for driving the rollers of the inking apparatus 2.

The impression cylinder 5 is disposed in eccentric bushings which permit a slight swinging motion of the impression cylinder 5 in the direction away from the plate cylinder 6 and toward the delivery drum 22 in case of incorrect feeding and response of the fingers 11.

The different conditions when throwing ol impression in existing drives and in the drive according to the invention are indicated in Figs. 3 and 4. While the impression cylinder 5 had to be moved hitherto a considerable distance about tangentially to the plate cylinder 6 and the delivery drum 22 to obtain the free space between impression cylinder and plate cylinder for throwing off impression (Fig. 3), a much smaller movement of the impression cylinder radially to the plate cylinder 6 will now be sufficient to provide the necessary clearance (Fig. 4).

I claim:

1. A rotary sheet printing press mechanism, compris- Y 3 ofsaid delivery drum said-impression cylinder being movable awayy from said` platev cylinder towardsA -saiddef livery drum.

2. A mechanism as claimed in claim 1 wherein said power source comprises a shaft and spaced gears onsaid shaft, said spaced gears bein'g coupled. respectively to.

said impression cylinder and` said deliver-ydrum, Asaid UNITED STATES PATENTS Terrey Apr. 17, 1923 Livingston Sept. 29, 1942 Crafts Apr. 13, 1948 Riggs et al. Aug. 24, 1948 Goodwin Aug. 8, 1950 I-.Iuclcv et al. V May 27, 1952 Brigham Sept. 9, 1952

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