US2088541A - Printing press - Google Patents

Description

M. S. THOMAS PRINTING PRESS July 27, 1937.

Filed June 10, 1935 miss .55.

Patented July 27, 1937 UNITED STATES PATENT OFFICE PRINTING PREss Mark StThomas, Green Bay, Wis. Application Jane 10, 1935, Serial No. 25,913 r 3 Claims (01. 101-228) This invention relates to printing presses of the continuous web rotary type and has for an object to provide novel means for varying the surface speed of the plate cylinder relatively to the surface speed of the tympan roll between printings to effect, a. predetermined spacing between printed impressions.

The invention generally comprises plate cylinder advancing or retarding means operable between the printings to vary the speed ratio of the plate cylinder relatively to the tympanroll, and quiescent during the printings to permit the plate cylinder to have identical surface speed relatively to the tympan roll.

The invention includes specifically a diiferential gear drive for the plate cylinder controlled by a cam to speed up or retard the plate cylinder to a predetermined speed ratio relatively to the tympan roll between printings.

With the above and other objects in view the invention consists of certain novel details of construction and combinations of parts hereinafter fully described and claimed, it being understood that various modifications may be resorted to within the scope of the appended claims without departing from the spirit or sacrificing any of the advantages of the invention.

In the accompanying drawing forming part of this specification,

Figure 1 is a front elevation partly in section of a web printing rotary press constructed in accordance with the invention.

Figure 2 is a detail cross sectional View taken on the line 22 of Figure 1.

Referring now to the drawing in which like characters of reference designate similar parts in the various views, l0 designates a tympan roll and Il designates a plate cylinder, the plate cylinder in this instance being shown as the same in diameter as the tympan roll so that ordinarily it would make one revolution for each impression or printing and spacing. The tympan roll and the plate cylinder are mounted in frames l2 and rotatable on journal boxes I3.

The plate cylinder II is loosely mounted on a shaft 14 which is provided with bearings l4 disposed concentrically in the journal boxes I3 of the plate cylinder. At one end of the shaft I4 is a drive l5 of equal ratio to the diameters of the tympan roll and plate cylinder and in the present instance this drive is shown as a belt gear device of convention-a1 type. The opposite end of the driven shaft I4 is connected to the loose plate cylinder by a difierential gear mechanism whereby the speed of the cylinder may be advanced or retarded relatively to the speed of the shaft as will nowbe described. The differential gear mechanism'comprises a gear I! which is fixed on the hub of the plate cylinder H and meshes witha difierential pinion !8 which is mounted on a spider l9 and in turn'meshes with a gear 2ll. The'gears l1, l8 v and 20 are'housed within a gear case 16 having formed integral therewith a ring-gear 2! which meshes with ai gear 22 fixed to the'shaft 23 10 of the tympan roll 18;- -'Ihe"gearratio between the ring gear' 2! and-drive gear- 22 isthe same ratio as the drive 15 on the opposite side of the roll.

The end of the driven shaft I4 is provided with 15 splines 24 over which is slidably fitted a sleeve 25 the bore of which is splined to interfit with the splines 24 so that the sleeve is confined to reciprocatory movement longitudinally of the end of the shaft Hi. The outer surface of the 20 sleeve is provided with helical splines 26 which interfit with similar splines 21 formed in the hub of the gear 20. The outer end of the sleeve is uniformly re-, duced and mounted thereon is an annulus. 28 which projects into the groove of a cam 29 that may be rotated by any convenient rotating part of the printing press to oscillate the sleeve 25 inwardly or outwardly upon the splined end 24 of the shaft, according to the pitch of the cam 30 groove. Cams of various pitches may be interchanged with the cam 29 to confine the throw or travel of the sleeve 25 to predetermined limits. The plate 30 is fastened to the surface of the plate cylinder in the conventional manner. If only one plate is used then onlyone impression can be made with one revolution of the cylinder. This means that the plate will register with the tympan roll once during each revolution and the distance between printed impressions 32 on 40 the web 3| will be equal to the circumference of the plate cylinder. Now assume that this distance should be greater or less than the circumference of the plate cylinder. A cam 29 is selected which will move the annulus 28 to the 45 right or left to a predetermined extent. This moves the sleeve 25 in the hub 21 of thegear 20 and by virtue of the interengaging spiral splines of the gear and sleeve, the gear 20 ,is speeded up or retarded as the case may be. This movement is transmitted through the planetary gear l8 to the side gear I! and the latter will be speeded up or retarded accordingly, and being fixed to the hub of the plate cylinder, will drive the plate cylinder at a greater or less 55 speed relatively to the tympan roll than would be the case if the plate cylinder were constantly driven at true gear ratio speed. During the impression or printing time, the tympan roll is, of course, running at the surface speed of the web being printed and at the same identical surface speed as the'plate cylinder H and at this time the cam is at one limit of movement or at a position of rest so far as the sleeve 25 is concerned so that the differential gears 20 and I! are moving as a unit at the identical speed of the shaft I4 and gear drive l5. Only between printings is the differential gear drive operated to vary the speed of the plate cylinder I l relatively to the tympan roll. I0. It will be pointed out moreover that the printing or impression cylinder may be advanced during at least one revolution of the cylinder so as to shorten the space between the next printing. If desired, an alternate short and long printing may be had, or one impression, namely, the long impression may be skipped. Where the splines are so arranged as to retard the impression cylinder the longer printing may be used and the shorter printing skipped.

The cam and splines therefore constitute periodically actuated means for alternately advancing and retarding the plate cylinderrelative to the tympan; roll.

From the above description it is thought that the construction and operation of my invention will be fully understood without further explanation.

What is claimed is:

1. In a web printing rotary press, a plate cylinder, a tympan roll, means for rotating the cylinder and roll at equal surface speeds, said means including a difierential gear, splined means associated with said gear, and cam operating means for periodically reciprocating said splined means, said splined means upon movement in one direction advancing .said cylinder relative to said roll, movement of the splined means in the opposite direction returning said cylinder to its original position relative to said roll.

2. In a web printing rotary press, a plate cylinder, a tympan roll, means for rotating the cylinder and roll at equal surface speeds, said means including a differential gear, splined means operatively connected to said differential gear, cam means, and means carried by said splined means engaging said cam means for periodically reciprocating said splined means, movement of said splined means in one direction advancing said cylinder relative to said roll, and movement of said splined means in the 0pposite direction retarding said cylinder relative to the roll.

3. In a web printing rotary press, a plate cylinder, a tympan roll, means for rotating the cylinder and roll at equal surface speeds, and periodically actuated means for alternately advancing and retarding said cylinder relative to said roll.

MARK S. THOMAS.

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