US2039472A - Printing press tension device - Google Patents

Description

May 5,1936. H. A. w. WOOD PRINTING PRESS TENSION DEVICE Filed March 10, 1934 3 Sheets-Sheet 1 May 5, 193%- H. A. w. WOOD $039,472

PRINTING PRESS TENSION DEVICE Filed March 10, 1954 3 Sheets-Sheet 2 May 5, 1936.

H. A. w. wooD PRINTING PRESS TENSION DEVICE Filed March 10, 1934 3 Sheets-Sheet 3 Patented May 5, 1936 UNITED STATES PATENT OFFICE PRINTING PRESS TENSION DEVICE Application March 10, 1934, Serial No. 714,918

2 Claims.

The principal objects of this invention are to provide means by which the reduction in size of the running roll to a butt increases the tension on the tension straps; and to provide a tension regulating means for the rolls which are gradually reducing in size that will not require the rotation of the reel to control the tension.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawings, in which Fig. 1 is an end View of a reel for carrying the web roll, said reel being provided with a preferred embodiment of this invention;

Fig. 2 is an elevation of the same, and

Figs. 3, 4, 5 and 6 show four different conditions of the running roll and show the gradual increase in tension on the straps as the roll reduces in size.

In printing presses which are supplied with paper from a web roll it is necessary to control the rotation of. the web roll through the pull of the web so that at all times there is sufiicient retardation to keep the paper taut as it is drawn into the press.

This invention relates to a type of tension Which retards the web roll by engaging its surface. In this type of retarding device it has been necessary heretofore to move the web roll, or rather, the

reel on which it is mounted, at intervals during its exhaustion in order to regulate the tension as is necessary. Furthermore, it has been rather difficult to obtain suflicient wrap around an expiring butt of the Web roll to insure sufiicient tension for good printing.

This invention is designed to provide such an arrangement of tension levers that when the roll is reduced to a butt and the tension straps are in nearly a straight line the greatest pressure will be exerted on the straps to give tension to the Web and prevent speeding up of the web as it runs into the press.

Figs. 1 and 2 show the usual pedestals 2 to provide a mounting for a shaft 3 on which are carried spiders 4 rotating with the shaft and constituting a reel having arms provided with spindles 5 for supporting the several web rolls. The device is shown as being provided with a motor 6 and a pinion I on its shaft meshing with a gear 8 fixedly connected with which is a worm 9 for driving a worm wheel ID on the shaft 3.

This device is provided with a series of tension straps I I adapted to engage the web roll R. One end of each strap is detachably secured to the floor by a bracket I2, shaft I3 and hook I4. The

other end of each strap is individually pivoted to one end of a lever I5. Each lever I5 is pivotally mounted on a shaft I8 which is secured to the bracket I9 on the frame of the press.

Pivotally secured to one arm II of the lever I5 5 is a rod 20 depending therefrom, with removable and adjustable weights ZI carried thereby. The lever I5 is provided with two arms I6 and I! which make an angle less than with each other, preferably an obtuse angle. With a con- 10 stant number of weights 2| the tension on the web W coming from the expiring roll R in Fig. 1 will be of a similar amount to that obtained when a full sizedroll is being used as shown in dotted lines in Fig. 1. This comes about for the reason 15 that the arm I6 of the tension lever I5 is rotated in a counter-clockwise direction in Fig. 1 to accommodate a full sized roll and the end I1 is swung to the same degree. The weights 2| become less effective for the reason that they are 20 nearer to the axis on which the lever oscillates. Thus with less eifective pull on the top end of the strap II, as shown in dotted lines in Fig. 1, an increased wrap around the full roll will give substantially the same tension to the web being 5 fed to the press as when the butt is being used up. The position assumed to accommodate a butt is shown in full lines in Fig. l and in this case the weights act at a greater distance from the center of the lever while the arm of the lever I6 30 on the other side provides a shorter leverage and the pull is increased.

Figs. 3, 4, 5 and 6 show progressively that, as

- the paper roll is used up, the several levers I5 all rotate in a clockwise direction increasing the pull 35 on the straps I I as the contact with the roll decreases. By this compensation the tension of the web going to the press is substantially the same at all times and this result is secured by the most simple automatic means obtainable. 40

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:-

1. In a tension device for a web supply roll for 45 a printing press, the combination of flexible tension straps for the roll fixed at their lower ends,

- levers, each having two arms at an angle to each other, to the ends of the arms on one side the upper ends of which straps are connected, and 50 means connected with the opposite arms of the levers for proportionately adding to the force exerted by said straps on the surface of the roll as it decreases in diameter.

2. In a tension device for the purpose described, 55

the combination with tension straps, of a. corresponding number of levers each having two arms at an obtuse angle to each other, whereby when either arm is horizontal the other arm of the same lever will extend upwardly from the fulcrum of the lever at an angle to the horizontal,

said tension straps each being connected to one arm of a lever, the other arms having adjustable weights thereon, whereby the efiective weight of the weights depends on the angular positions 0,1. the two arms of the levers.

HENRY A. WISE WOOD.

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