US2813485A

US2813485A - Inking mechanisms for printing machines

Info

Publication number: US2813485A
Application number: US296603A
Authority: US
Inventors: Charles A Harless
Original assignee: R Hoe and Co Inc
Current assignee: R Hoe and Co Inc
Priority date: 1952-07-01
Filing date: 1952-07-01
Publication date: 1957-11-19
Anticipated expiration: 1974-11-19

Description

Nov. 19, 1957 c. A. /HARLEss INKING MECHANISMS FOR PRINTING MACHINES Filed July l. 1952 2 Sheets-Sheet 1 -%'I-NVToR.

2 Sheets-Sheet 2 Nov. 19, 1957 c. A. HARLEss INKING MECHANISMS FOR PRINTING' MACHINES Filed July 1. 1952 United States Patent C) INKING MECHANISMS FOR PRINTING MACHINES Charles A. Harless, Riverside, Conn., assignor to R. Hoe & Co., Inc., New York, N. Y., a corporation of New York Application July 1, 1952, Serial No. 296,603

3 Claims. (Cl. 101-366) fed through a number of conduits by a number of small pumps.

It is an object of the invention to improve the pumping cycle in an nking mechanism of the character indicated, so as to permit more efficient handling of the ink.

Another object of the invention is to provide an 2,813,485 Patented Nov. 19, 1957 cylinder bores in the member receiveI the piston plungers 13, which reciprocate vertically therein. The plstons are urged downwardly by springs 14 accommodated within a chamber formed in the member 10 and the` bottom of which is closed oif by a plate 16. The lower ends of the pistons carry cam follower rollers 17 and` are prevented from rotating by a downwardly depending flange 1S formed on the plate 16 against which the flat cheeks of the lower ends of the pistons may slide. The piston motion is produced by a cam rotated by means of a shaft 21, the cam movement being communicated` to the pistons through intermediate cam follower arms 22 rotatably carried on` a shaft 23. Each arm 22 carries a cam follower roller 24, cooperating with the cam 20, and is formed with an upper table or surface upon which the roller 17 at the bottom of the associated piston rests. for engaging the other end of the arm 22 for limiting the piston stroke to reduce the amount of ink pumped when desired. i

The member 10 reciprocates between a position in which` its cylinder bores communicate with the discharge the accompanying drawing, and the features embodying t the invention will then be pointed out in the appended claims.

ln the drawing:v b

Figure l is a cross section through an inking mechanism embodying the invention in a preferred form;

Figure 2 is a view similar to Figure 1, but showing the parts in another operating position, and eliminating certain structure of Figure 1 to clarify the showing of certain parts;

Figure 3 is a rear elevation of the pumping mechanism of Figure 1, partly broken away so as to show the parts as seen in section on the lines 3-3 and 3'- of Figure l; and

Figure 4 is a section on the line 4-4 of Figure 2.

There is indicated in phantom at 1 an ink drum which, as will be understood, supplies ink to a printing cylinder through a train of transfer and distributing drums and rollers in the usual way.

The inking mechanism of the invention may be supported in any convenient way (not shown) in the press frame, and comprises basically a plate 2 in which the ports for supplying the pumps with ink and discharging the ink pumped by them are formed, and in which the conduits for delivering the ink are also formed. There is supported on top of the member 2 an ink trough 3, and a pump housing 4 is fixed to the bottom of the member 2. The ink is supplied to the pumps through the suction ports 5 in the member 2 and the ink discharged by the pumps is received in the discharge ports 6 also formed in the member 2 and communicating with conduits 7, which deliver the ink to the drum 1. The pumps are carried in a member 10 slidably supported in guides 11 on the underside of the member 2 and reciprocated axially as by means of a cam 12 (Figure 3). A number of leakage.

ports 6 (as shown in Figures l and 3) and a position in which these cylinder bores communicate with the intakeV or suction ports 5 (as shown in Figures 2 and 4). As will be understood, the reciprocation of the member 10 and the rotation of the cam shaft 21 will be synchronized in the usual Way so as to properly relate the movement of the pistons and the position of the cylinder bores with relation to the suction and discharge ports.

The housing 4 will preferably be filled with oil to a height that will submerge the lower part of the member 10, for lubricating the pumps and other parts, since separation of oil from the ink within the trough 3 of the pumping system is provided for.

A number of bores 30 are provided in the upper part of the member 10 and lead from grooves 31 in its upper surface into the chamber 15 within the member 10. Any mixed oil and ink which may be produced between the upper surface of the member 10 and the lower surface of the member 2 will, accordingly, collect in theV chamber 15 and may be withdrawn either periodically or continuously, as desired. The

members

10 and 16 taken together form a cylinder block having the necessary bores for accommodating the pistons and also having the conduits 30 and chamber 15 for handling the In its broader aspect, the invention is not conned to a specific way in which the cylinder block is formed, the specific form 0f this element being largely dictated by considerations such as convenience in casting and machining `the parts.

IA number of agitators 35 are supported from a member 36 reciprocably mounted externally of the trough 3 and reciprocated as by means of a strap and eccentric indicated at 37 in Figure 3. The agitators may take any desired form and may come as close to the bottom of the trough as is desired, the elimination of the usual pumping mechanism within the trough thus greatly simplifying the problem of providing satisfactory agitation for the ink. It will also be observed that the open and unobstructed form of the trough itself greatly simplifies the insertion of partitions at any desired points for separating the trough into sub-compartments for holding different colored inks to be applied to different columns or pages along the ink drum 1.

The cam 20 is formed with a rise for producing the pumping stroke, a high dwell to permit the pistons to remain stationary as their cylinder bores move from the discharge ports to the suction ports, a fall to permit the springs 13 to accomplish the suction stroke and a low dwell to permit the pistons to remain stationary as they A screw adjustable member 26 is mountedl 3, move back from the suction ports to the discharge ports.Y

Where ink supply less than the maximum is desired, the` members 26 are turned so as to depress the outer ends of the follower arms 22, thus preventing the'roll'ers 24 from following'the fall' of the cam all the way downA tothe low dwell and regulating the stroke of thepistons accordingly.

LIn most practical ink pump constructions as heretofore made, the motion of the pistons has been harmonic orJ substantially so, the motion in one direction being producedl by an eccentric andthe motion in the other by a spring, and the reduction in pumping4 rate of the individual pumps has been accomplished by means of a suitable stop screw or the like, limiting the return movement by the spring and thus chopping off part of the harmonic curve. In the firstk place, the stroke at'full pumping rate in such constructions is limited as to thelengths` ofthe pumping suction strokes by the geometery of the situation in such a way that these strokes are equal in pointy of time or approximatelyso, and are limited in each case to about 90` of rotation of the eccentric driving shaft; The limitation ofthe stroke to provide reducedpumping involves not only a reduction in travel ofthepistons but a postponement ofv the time when the suction stroke commences, shortening the time duration of this stroke and causing a corresponding shortening of the discharge stroke. Any shortening of the discharge stroke is disadvantageous as it increases the interval between the successive supplies of ink to the ink drum and thus requires more working and distribution of the ink in the ink motion, while shortening the suction stroke is also disadvantageous in thatA it makes it more difficult to be sure that the cylinders arefilled, particularly where very thick inks are used.

With the mechanism of the present invention, it becomes possible to reduce the dwells of the camV 12 to practically any desiredv angle of its rotation, the reciprocating movement of the piston carrying member being correspondingly quickened. By arranging the leads of the cam 12so as to synchronize with the dwells of the cam 20, the time of duration of the suction and discharge strokes ofthe pistons may be correspondingly increased. Furthermore, the lengths of the suction and the discharge strokes need not be equal. For example, when the consistency of the ink to be used is such that it* flows readily into the intake ports, the time givento the suction stroke may be abbreviated and the time given to the discharge strokecorrespondingly prolonged, thus supplying the ink more uniformly. than heretofore possible around the periphery of the ink drum 1'. On the other hand', if the ink to be used is quite stiif, it may be advantageous to prolong the suction stroke and correspondingly abbreviate the discharge stroke.

While adjustment for reduced in k supply utilizing the mechanism disclosed, involves a reduction of the working strokes in point of time, the working strokes may nevertheless be considerably increased by comparison with conventional inking mechanisms such as are discussed above, at correspondingly reduced pumping rates. Since the quantity of ink to be received in the cylinder bores and to be worked up in the ink motion is reduced correspondingly when the piston travel is shortened, a very satisfactory operation at reduced pumping speeds as well as -at full stroke may be obtained.

What is claimed is:

l. In an inking mechanism for printing machines, and in combination,` ink pumping mechanism, an ink trough positioned above the same, a port and conduit plate interposed between the trough and inking mechanism, the plate having intake ports extending through it, conduits for Supplying ink to an ink drum and discharge ports in itsy lower surface and communicating with the said conduits, the ink pumping mechanism comprising a cylinder-block having'a pluralityof cylinder bores and pistons reciprocable therein, and means for movingy the said cylinder `block to a position where the cylinder bores register withl the intake ports and to a position where the cylinder bores register with the discharge ports;

2; In an inking mechanism for printing machines, and in combination, inkl pumping mechanism, an ink trough positioned above the same, a port and conduit plate interposed between the trough and inking mechanism, the plate'having intake ports extending through it, conduits for supplying ink to an ink drum and discharge ports itt-its lower surface and communicating with the said conduits, the ink pumpingy mechanism comprising a cylinder block having a plurality of cylinder bores and pistons reciprocable therein, and means for moving the said cylinder blockl toV a` position where the cylinder bores register'with the intake ports and to a position where the cylinder bores register with the discharge ports, the cylinderl block also havingy a chamber for receiving leakage occurring between it and the port and conduit plate and communicating through openings spaced from the cylinder bores with the upper surface of the cylinder block.

3. The combination according to claim 2, in which the cylinder-block also has grooves in its upper surface for receivingv leakagev and conducting it` through said openings into the leakage chamber;

References Cited in the file of this patent UNITED STATES PATENTS 1,348,900- Schmidt Aug. 10, 1920 1,775,612.. Yingling Sept. 9, 1930 2,081,224 Coberly et al May 25, 1937