US2644394A

US2644394A - Rotary intaglio doctor mechanism

Info

Publication number: US2644394A
Application number: US65155A
Authority: US
Inventors: Charles A Harless
Original assignee: R Hoe and Co Inc
Current assignee: R Hoe and Co Inc
Priority date: 1948-12-14
Filing date: 1948-12-14
Publication date: 1953-07-07
Anticipated expiration: 1970-07-07

Description

July 7, 1953 c. A. HARLEss 2,644,394

ROTARY INTAGLIO DOCTOR MECHANISM Fild Dec. 14, 194e 3 sheets-Sheet 1 Afro/@mfr 3 Sheets-Sheet 2 -Filed Dec.

./IIWMA. A.lw bmw. Y um., E E g 9 g j Wl. f. i I f LH@ CH/LQLE'S A. HALFSH July 7, 1953 c. A. HARLEss f 2,644,394

ROTARY INTAGLIo DOCTOR MEcHANxsM Filed Dec. 14, 1948 5 Sheets-Sheet 3 Patented July 7, 1953 YUNITED STATESr ,einer ROTARY N'IAGLIO DOCTOR MECHANISM Charles A. Hairless, Riverside, Conn., assigner to` l. lice a Co., Inc., New

tien of New York York, N.v Y., a corpora= Application' Becember 1d, i948, Serial No. 65,155

This invention relates to rotary intaglio doctor mechanisms. c

It is an object of the invention to providevimproved doctor mechanism by means of which the doctor is moved into and out of operating relation to the cylinder and may be adjusted with certainty and safety.

A further object of the invention is to provide doctor operating mechanism of the type indicated in conjunction with doctor pressure regulating `mechanism of a yieldable spring operated type.

The mechanism of the present invention is an improvement upon the doctor mechanism shown and described in Huck application Serial No. 60,075 filed November 15, 1948, for Doctor Mechanism.

With the foregoing and other objects in view, which will appear as the description proceeds, the invention resides in the combinations and arrangements of parts and in the details ci" copstruction hereinafter described and claimed.

In the drawing:

Figure 1 is an end elevational view of the doctor mechanism embodying the invention in a preferredfform of embodiment,v certain parts being omitted for clarity in the showing;

Figure 1A is a detail view of a portion of Figure 1 showing certain parts omitted from Figure l;

Figure 2 is a plan view of the doctor mechanism of Figure 1; f

Figure 3 is a rear elevational View of the doctor mechanism of Figure 1;

Figure 4 is a section on the line i-- of Figure 2; and

Figure 5 is a section on the line 5-5 of Figure 4.

In Figure 1 there is indicated an intaglio print ing cylinder l carried on a shaft 2 lwhich is journaled as usual in the press frames. A housing 3 may enclose the major part of the cylinder l. The doctor blade d is' carried in a doctor holder 5 having' an angle 6. The doctor blade assembly may be of `any desired type and hence is not shown and described in detail herein. The mechanism by whichl the doctor blade assembly 5 is supported comprises a bar l 'exterrftn ing the length thereof and having a slot to receive the angle B, the doctor blade assembly being held therein as by means of clamps 3. The bar in turn, is fastened to a pair of arms s formed as hollow housings and generally similar to the corresponding arms of theA Huck application before referred to. These arms are'pivotally carried by means of bearings lil on a shaft i i, which in turn is carried inbearing l2 of posts or pedesf' 11 ijlairnss (Cl. 10b-e157) tals la which are fixed tothe usual sliding carriage I4. The sliding carriage I4 is supported on tracks I5, which are attached to the machine frames I6 (Figs. 2 and 3), and is reciprocated by a doctor reciprocating mechanism Il through a connecting link I3 and stub shaft and bearing assembly i9.

Within each housing 9 is positioned an armlil which is fixed to the shaft Il. The doctor pressure is regulated by adjusting springs reacting between arms 9 and 2t as in they Huck applica' tion and shaft I l is rotated for moving the d octor into and out of operating position by means of a worm wheel unit 2l, as will be hereinafter described in detail.

Assuming shaft l I to have been set into operating position as shown in Figure l, the operation of the parts is as followsf: Springs 25 received within a bore of each arm 20 reactagainst the rear wall of each pvoted housing 9 for counten y balancing the weight of the doctor assembly, the

n asto reduce the pressure which would otherwise f side the housings 9, are adjustably-connected to bar i and the arms 9. The pressure of springs 25 may be adjusted by means of threaded members Z6, access thereto being provided through openings 2l in the housings 9. Further springs 28 are carried on slidable poppet rods 29 which are received within sockets 3Q. Each spring 25 acts between a member 3| attached to a rod 2t and the material of its housing 9 surrounding socket 39. An adjusting-rod 32 is threadably carried in the upper part of each arm 20 and presses against the end of its rod 2e. Handles 33 pro= vide for turning the rods 32 so as to increase and decrease the pressure exerted between the arms 2d and the arms 9. This pressure opposes thepressure of springs 25. As explained in the Huck application previously mentioned, the net effect of the springs 25 and 2B is normally such be applied to the doctor by the weight vof the parts.,` Pressure gages 34, readable from outthe members 3l, as inthe Huck application.

' Each arm 20 carries a stub shaft 40 which protrudes loutwardly from a housing ,9, passing through an opening 4I therein (Figs. A1A and 3). Outside the housings 8 the stub shafts in are each provided with an operating handle (i2 and a catch 43, which cooperates with a stud M mounted on an upward extension l5 of each pedestal I3. Studs '44 may be adjustable as by means of eccentric mountings therefor.v The upper extension d5 of each pedestal also carries an adjustable stop 46 which cooperates with a collar il concentric with shaft 40. Shafts 4!) ings 9 by means of bolts 5i).

further carry eccentrics 48 which seat in depressions formed in blocks 49 attached to the hous- With the handles 42 in the forward position as indicated in Figure 1A, the low point of eccentrics 48 will be facing the members 49, while retracting these handles (clockwise, Fig. 1A) will bring the high point of the eccentrics 48 against members 49.

The action of the parts just described is as follows: Assuming the parts to be in the operating position of Figure 1A and that it is desired to swing the doctor back from the cylinder, the handles l2 are first pulled backward. The eifect of this is to disengage the hooks or latches 43 from studs 64, thus freeing arms 2l! for backward (clockwise) movement. Further movement of the handles i2 causes theeccentrics G8 rst to engage the blocks 4S and then to exert pressure thereagainst, forcing the arms 9 clockwise with relation to arms 2i] by a small distance and lifting the doctor blade off the cylinder. This movement ordinarily need not exceed one-tenth of an inch or thereabouts. Arms 9 and 2li now being held together by engagement of the eccentrics 48 with the blocks 4.9, the shaft II is rotated (clockwise) by manipulation of the worm and gear unit 2l to swing the whole doctor assembly back from the cylinder. This involves a movement through approximately 60". When restoring the doctor to operating position, worm and gear unit 2l is operated to rotate the shaft II counter-clockwise until collars l? are brought against the adjustable stops 46. Handles 42 being still in their rearward position, the eccentrics 48 will still be holding back the arms 2B so that the doctor blade is held slightly olf the cylinder and any possible damage is prevented. Handles 42 are now pushed into the position of Figure 1A, first gradually releasing arms S so that they may rotate counter-clockwise under the resultant effect of gravity and the combined action of v springs and 28, until the doctor is resting on the cylinder with the preset pressure and then engaging the hooks or latches 43 over the studs 45 to lock the mechanism in this position.

The warm and gear unit 2l for operating the shaft I I is shown in detail in Figures 4 and 5 and comprises a housing 6E through which the shaft II passes and which carries in antifriction bearings a worm wheel shaft 6I operated by means of a counterbalanced crank 52. The worm 63 meshes with a worm wheel sector 64 xed to the shaft II so that turning the crank E2 will rotate shaft II and move the doctor mechanism in the desired manner. rThe hub of the worm wheel sector 54 carries projections 55 to which poppet rods '66 are pivotally connected at 5l. Each rod 66 extends into a socket 68 formed in the housing 6G, the socket @3 being of larger diameter than the rod, as indicated, to accommodate pivotal movement of the rod. A thrust washer il? reacts against the material of housing 66 surrounding the socket 63 and a cross plate or bar 'II seats against washers l2 xed to the rods 66. Springs 'I3 are interposed between the plates 'H and thrust washers 'I0 tending to force the poppet rods 5B downwardly and thus tending to rotate the shaft EI clockwise or in a direction to lift the doctor mechanism 01T the cylinder.

As will be apparent from Figure l of the drawing, the center of Vgravity of the parts carried by the shaft I I is considerably displaced to the left of a vertical line through the center of the shaft, creating a moment due to the force of gravity, in a counter-clockwise direction in Figure 1. As

the shaft is rotated back from operating position, this moment will decrease sinusoidally, since the moment arm is proportional to the sine of the angle which a line, through the center of shaft I I and the center of gravity of the supported parts, makes with the vertical. In consequence, for equal angular movements, the change in the gravity moment about the pivotal axis is greater at the beginning and decreases as the center of gravity approaches a position directly above the pivotal axis. Close counterbalancing requires that the counter moment due to the springs 'I3 will at all times be equal to and opposite in direction to that of the gravity moment, and that the actual change of moment be substantially sinusoidal. Such a characteristic of the spring counterbalance can readily be obtained with the construction shown in Figure 4 and in a very simple manner. As will be observed from that figure, clockwise movement of the shaft II causes expansion of the springs '13, reducing the force exerted thereby, substantially in proportion to the expansion, and with a resultant counter-balancing moment which changes in amount from a maximum, in the position shown in Figure Li, to zero at the time in the cycle when the center of gravity of the parts carried on the shaft II is directly over the axis of the shaft. At this time the springs 'FS are neutral and exert no force as the snap rings which are held in recesses in poppets Sii, engage the upper ends of springs 73, the lower ends of which are resting on plate lI which in turn is resting on ledges 'i5 of the housing Eil. Further rotation of shaft I I, in a clockwise direction, will then compress springs 'i3 from above in a manner to counter-balance the weight of the parts carried on the shaft il, as the center of gravity moves to the right of a vertical line through the axis of that shaft. Since the eccentrics i8 hold the doctor supporting arms and the doctor and associated parts in fixed relation to the operating arms throughout the movement to and from operating position, oscillation of these parts against the springs and consequent disturbance of balance iseliminated.

What is claimed is:

1. In a rotary intaglio doctor mechanism and in combination, a pivotally mounted doctor supporting arm, a pivotally mounted operating arm for swinging the supporting arm toward and away from a printing cylinder, an eccentric movably carried by the operating arm, the supporting arm having a cooperating surface positioned for engagement by said eccentric, the eccentric being located between the said cooperating surface and the printing cylinder, a stop limiting movement of the operating arm toward the cylinder, and means for moving the eccentric to engage the cooperating surface to hold the doctor supporting arm back from the cylinder and for moving the eccentric to disengage the cooperating surface and permit movement of the doctor supporting arm toward the cylinder.

2. Mechanism according to claim l, comprising also a catch for holding the operating arm against the stop, the catch being connected to the eccentric for movement therewith.

3. In a rotary intaglio doctor mechanism and in combination, a shaft, an operating arm xe-d thereto, an eccentric rotatably carried by the operating arm, a doctor, supporting arm rotatably carried by the shaft for movement toward and away from a printing cylinder by the operating arm and having a cooperating surface positioned for engagement by said eccentric, the eccentric being located between the said cooperating surface and the printing cylinder, a stop limiting rotation of the operating arm toward the printing cylinder, and means for turning the eccentric to engage the cooperating surface to hold the doctor supporting arm lback from movement toward the cylinder and for turning the eccentric to disengage the cooperating surface and permit movement of the doctor supporting arm toward the cylinder.

4. Mechanism according tc claim 3, comprising also a catch for holding the operating arm against the stop, the catch being connected to the eccentric for movement therewith.

5. In a rotary intaglio doctor mechanism, and in combination, a shaft, doctor supporting arms pivotally mounted on the shaft, operating arms fixed to the shaft, spring means acting between the doctor supporting arms and the said operating arms for regulating the doctor pressure. means for rotating the shaft to swing the doctor to and from operatingposition and spring means for counterbalancing the weight of the doctor and other parts carried by the shaft.

6. The combination according to claim 5, com-l prising also releasable means for holding the doctor supporting arms to the operating arms against movement toward a printing cylinder.

7. In a rotary intaglio doctor mechanism having a doctor pivotally mounted on a shaft for movement therewith by members fixed to the shaft and in which the printing pressure is adjusted by means of spring means acting between the doctor supporting arms and the said members, the combination with a means for rotating the shaft to swing the doctor to and from operating position, of spring means for counterbalancing the weight of the doctor and other parts carried by the shaft.

8. 'Ihe combination according to claim 7, in which the counterbalancing spring means is Iconnected to the shaft so that it expands as the shaft is rotated to swing the doctor away from operating position, thus decreasing the spring force, and comprising also means varying the moment arm of the spring'force about the shaft axis for maintaining the spring moment substantially equal to the gravity moment about the shaft.

9. In a rotary intaglio doctorvmechanisrn and in combination, a shaft, an operating arm fixed thereto, an eccentric rotatably carried by the operating arm, a doctor supporting arm rotatably carried by the shaft for movement toward and away from a printing cylinder and having a cooperating surface positioned for engagement by Said eccentric, the eccentric being located between the said cooperating lsurface and the printing cylinder, a stop limiting rotation of the operating arm toward operating position, and means for turning the eccentric to engage the cooperating surface to hold the doctor supporting arm back'from operating position and for turning the eccentric to disengage the cooperating surface and permit movement of the doctor supporting arm toward operating position.

10. Mechanism according to claim 9, comprising also adjustable spring means acting between the operating arm and supporting arm for regulating the doctor pressure. 11. Mechanism according to claim 9,'comprising also a catch for holding the operating arm against the stop, the catch being connected to the ecccentric for movement therewith.

CHARLES A. HARLESS.

References cited in the me of this rpatent UNITED STATES PATENTS