US288872A - Walter sgott - Google Patents

Description

(No Model.)

W. SCOTT. GUSHIONING APPARATUS EUR PRINTING PRESSES.

Patented Nov. 20, v1883. i

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UNITED v STATES PATENT OFFICE.

WALTER sooTT, or PLAINEIELD, NEW JERSEY.

CUSHI'ONING APPARATUSV FOR PRINTING-PRESSES.

` SPECIFICATION forming part of Letters Patent No. 288,872,4dated November 20, 1883.

Application filed February Q3, 186B. (No model.) Y

To noi/Z whom, t may con/cern:

Be it known that I, VALTER SCOTT, of

` Plainfield, in theeounty of Union and State of New Jersey-have invented an Improvement in Cushioning Apparatus for Printing- Presses, of which'the following is a specificavPrintingpresses have been made With a cylinder beneath the reciprocating bed, and stationary pistons or plungers, over which the cylinder passes near the ends of the stroke, so as vto check the momentum of the bed and types, and canse the press to run more uniformly. Vith these cushioning-cylinders th ere is usually more Ior less vacuum action as the cylinder draws off the piston, and a disagreeable noise is produced as the air rushes into the cylinder. Valves have been used to admit air into the cylinder as the same draws off the piston, and they usually close and confine the air Whenever the pressure increases in the cylinder and act independent of the Weight to be arrested.

. The object of my invention is, first, to open .the valve at a time when the pressure within the cylinder is about the same as that of the atmosphere, and thereby prevent the vacuum action tending to retard the momentum of the bed, as heretofore usual; second, to close the valve automatically at the proper time, so that more or less air will be conned in proportion to the Weight of form upon the bed, and the momentum of the bed will be stopped at the end of the stroke; third, to allow the pistonpaclring to yield inwardly Without injury in cases Where apiece of paper or other substance may fall upon the piston or into the cylinder, so that injury maybe prevented; and, fourth, to expand the packing of the piston as it may become Worn, but only to expand it suiiiciently to make it come into contact with the interior oi' the cylinder.

In the draWings,Figure l is a section oi' the cushioning-cylinder, and a representation of the other parts to which the invention relates. Fig. 2 is a face view 5 Fig. 3, a section in larger size of the yielding piston. Fig. Ll is a side view, and Fig. 5 an edge view of the cams that operate'the valves.

The partsof the press are to be of l any usual or desired character.

The frame is indicated by the dotted outline A, the impression-cylinder by the circle B. The bed C is above the cushioning-cylinders D. There may be two of these cylindersone near each end of the bed-or there may be but one such cylinder with a central partition, as shown.

The pistons or plungers E are represented as sustained by the hollow rods F and crossframes G, between the main frames A; but the cylinders may be transposed, so that the pistons are upon the bed and the cylinders stationary on the frame. In either instance there is an outlet-pipe from the cylinder or from the piston through the piston-rod, and an air-chamber, a, and valve b, that When closed confines the air to form the cushion, or when open allows the air to pass in or out of the cylinder freely.

I do not limit myself as to any particular construction, as my improvement is available vWith almost all forms of cushioning apparatus.

The shaft H is rotated in harmony with the other parts of the press. It is represented as deriving its motion from the shaft e of the impression-cylinder by the bevel-gears d e and shaft K, and upon this shaft H the camshereinafter described might be placed; but it will usually be preferable to employ cross-shafts h. h, driven by the bevel-gears k la. Similar devices vare at each end of the press, and the parts are timed to act properly with the bed at the opposite ends of its stroke. rIhe cam .L is made with a projection, 2, that acts upon the spindle of the valve b, and raises the same as the cylinder D is drawing off the piston E, and the parts are placed so that the cam lifts the valve at about the time that the pressure Within the cylinder is about the same as that of the atmosphere; hence the air will pass Yfreely into the cylinder as the same draws oft' the piston and prevent any vacuum action, and avoiding any noise, and, at the sametime removing any risk of vibration in the bed, caused by the sudden rush of air into the cyl inder. This cam should be secured to its shaft by a clampingscrew, in order to allow of the cam being adjusted to raise the valve at the required time.

The aforesaid device alonemay be used; but I prefer also to employ a second cam, n, upon cushion.

the same shaft with anelevation, 3, that holds the valve b open the required lengthv of time, and preventing it closing too soon, and as this cam passes from below the valve-stem such valve closes and confines the air. rIhe object of this is lto confine only the required amount of air, so that the accumulated pressure is enough to overcome the inertia of the' bed. If the valve is allowed to close sooner in the movement of the press, the cushioning action is increased so as to be sufiicient to stop a heavy form, and the reverse for light forms'. The cam n may be moved upon and clamped to the shaft h; but I have shown Ya screw and nut, 10, at the curved slot in the cam Ii, by means of which the two cams may be clamped together after adjustment. The index on the cam and the pointer upon the nut indicate the relative position of the cams when adapted to forms of different weights. Each piston is made with a stationary head, r, permanently attached to the piston-rod. The ring-follower s is held in place upon studs or columns s, extending out from the head r. Between 1- and s there is a flexible packing, t, connected at one edge with the expander u, and the other edge serves to form a tight joint with the intcrior of the cylinder D in retaining the air- The expander uis made in four or more sections, and it is provided with conoidal flanges 12 at its. inner edges. The sections do not set closely together, but they are guided by and between the studs s', and they are free to be pressed inwardly 'against the action of bow or helical springs 16, that are placed between the shaft and the inner portions of the said sections.v rIhese springs, if unrestricted in their action, would expand the i packing too much to allow it to enter within sheet or piece of paper falling upon the piston-and injury to the parts be prevented. By adjusting the retainer the expansive packing may be enlarged or contracted.

In many of the cushioning devices heretoesame fore used, the-pistons .are movable endwise of the piston-rods, so that they may act earlier or later in the stroke to confine the air. By my improvement this adjustment of the pistonsis dispensed with.

Any suitable valves or cocks may be used, and, if more convenient, air-pipes may be employed between the pistons and the valves, so that the valves or cocks and the automatic actuating mechanism may be placed in any convenient position on the press.

I claim as my invention- 1. The combination, with the reciprocating bed and air-cylinders and the stationary pistons in a printing-press, of a valve to confine the air, and an automatic lifting device, substantially as described, to open the valve when the pressure in the cylinder is reduced to about the same as that of the atmosphere, subit to close at the proper time, substantially as set forth.

4. rIlhe combination, with the expansive packing and the piston, of segmental expanders, a spring, and a retainer to adjust the .extent to which the expanders operate, substantially as set forth.

5. The combination, with the bed, cylinder, piston, and valve, of a cam to allow the valve to close, and an index for aiding in the adjustment of the cam so as to confine the air-cushion in proportion to the weight to be arrested, substantially as set forth.

6. The combination, with the bed'G and imnpression-cylinder B, of the cylinders, their pisytons E, valves Z1, the cams L, shafts h H K,

and bevel-gearing connecting the shafts, substantially as set forth.

Signed by me this 19th day of February, A.: D. 1883.

VALTER SCOTT. Vitnesses:

GEO. T. PINCKNEY, HAROLD SERRELL.

IOO

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