US2262573A - Color intensity control device for ink supply mechanism for printing presses - Google Patents

Description

Nov. 11,1941.

F. M. BENDER COLOR INTENSITY co NTROL DEVICE FOR INK SUPPLY MECHANISM FOR PRINTING PRESSES Filed Sept. 9, 1937 I 'BY I r I I v 1101252111311 YMJEA'MBMQ',

'HIA: ACTORNEXS Patented Nov. 11, 1941 UNITED STATES-- PATENT oFF cE COLOR INTENSITY CONTROI; DEVICE FOR INK SUPPLY MECHANISM FOR PRINTING PRESSES Application September 9, 1937, Serial No 163,0 21

' 7 Claims. (01. 137-78) 'Thisinvention relates toacolor intensity control device, and more particularly to a mechanism whereby the intensity of color of the inks fed to printing presses may be controlled within close limits.

In order to obtain a finished product of high quality in the color printing art, great care must be exercised to insure'that the intensity of color of the inks used remains constant during the printing process. Inasmuch as the intensity of 10 color of the inks varies during the operation, either additional ink or solvent must be added to restore the ink to the exact color intensity desired. This intensity of color heretofore has been usually determined by visual observation alone, and since the human eye is not sensitive to slight variations in color intensity, and is variably sensitive to any variations, the method is generally unsatisfactory.

An object of my invention is toprovide a greatly improved device by means of which slight changes in the intensity of color or the ink can be instantly detected and corrected.

it jurthernobjectof the invention is to provide a device of the above character in which the correction of the intensity of color of the ink is made automatically so that the color intensity of the ink can be maintained constant over long periods of operation.

The invention is attained by directing rays 01 3 light through a transparent chamber'inwhich the colored ink flows. The light so transmitted is passed through a complementary color filter with the result that changes in 'the intensity of tensity of the light emanating from the color filter. By comparing. the filtered light with light --o a standard intensity, changes in color in tensity of the ink may be instantly detected and corrected, or if desired, the-beam oi filtered 40 light may be made to maintain a constant ill-r f tensity of color of ink aut 'ma ally -V Additionalpbiects will be readily apparent I T' from the following detailed description and from ink may be supplied to a printing press in accordance with the present invention.-

Referrlng to Figure 1, the comparison device is designated by the number i and comprises a lamp G and a chamber 1 through which the If it is desired connected to the filament of the tube supply to" the tountain flows. The sides 8 and 9 orthe chamber 1 are of a transparent mate-- rial in order that light from the lamp 6 may be transmitted through the ink stream into a closed cylinder ll. ,At the open end otthe cylinder H there is secured a translucent aperturedjdisc l2, the aperture being covered by a light filter l3 which is complementary to the color of the ink fiowinginthe transparent chamber 1. with this construction anychange in the intensity of color of the ink supply ,results in a variation in the intensity of the light beam emanating from the filter l3.

cular aperture in which the cylinder H is received. Light from a lamp 6 impinges on the surface of the reflector l0 and is reflected to the.

translucent disc l2 which is so constructed that light passing through it is-oi the same intensity as light passing through the ink in the chamber 1 when the color intensity ofthe ink is correct. In this fashion, the disc l2 constitutes a standard of comparison against which the intensity of the light passing through the filter Hi can be checked.

If the ink in the chamber 1 becomes too light color, the intensity of the light from the filter l3 will increase relative to the standard, so that This device, therefore, can be used ,with a high degree of efiectiveness to visually indicate slight variations in the intensity of colors of inks. The variations in color can then be readily corrected by manually adding either more ink or anink so v t.- w

to corre'ctthe variations in the color intensity of the ink automatically,.it may be done by passing the beam of light from the filter I3 througha lens. H. The beam is focused on the photo-sensitive cell l5, which is connected through a wire it to the grid of a thyratron tube ll of the type known as a 112A thyratron tube.

The other side of the photo-sensitive cell II is I! througha wire l8 and two resistors I! and 20. In a typical circuit the resistor It has a value of 6000 ohms, while resistor Ill, is oi 600 ohms. 'lhe changes in the current of the' photosensitive tube appear sis-voltage variations lie-'- veloped in a resistor 2|, which is connected in a circuit 22 between the grid of the thyratron tube tron tube from a separate circuit. including a power transformer 25 in the primary circuit of which is a switch 21. The two extreme ends of the secondary winding of the transformer 26 are connected by means of the wires and 36 to one of the standard types or voltage regulator tubes 39 by means of which a constant alternating current voltage is maintained across-the wires 40 and 4|. From the wires 40 and 4| this constant voltwhere it is impressed across the resistors l8 and 42 in series. In this fashion an alternating current voltage of constant magnitude is available for the polarization of the photo-sensitive tube l5 and the energization of the filament and plate circuits of the tube l1.

The plate circuit of the tube l1 includes a wire 43, one of the windings of a polarized relay 44, a variable resistor 45 and the wire 40. A condenser 46 approximately l microfarad in value is shunt ed from the wire 43 to the. wire 25 in the filament circuit. The polarizing winding of the relay 4'4 is connected through the wire 43 to an extremity 49 of th resistor 42, while a second wire 41 is connected to a variable point 50 on the resistor 42.. t b

'By changing the position of the variable point 50, the voltage impressed on the polarizing winding of the relay 44 may be varied over'a considerable range. In this manner it is possible to set up in the relay core a magnetomotive force of the required magnitude and direction to ex--, actly balance out the magnetomotive force due to the current flowing in the main winding of the relay 44, which is in series with the plate of the tube H. In this balanced state, the permanently magnetized armature 5| of the relay 44 is maintained an intermediate position between two sets of contacts, due to the compression of the spring 52. As the ink supply becomesnarker tensityfthe photo-electric current decreases so that the\plate cur-rentin the tube I1 is correspondingly reduced; The magnetomotive force due to the polarizing winding then dominates, and forces the armature 5| downwardly to engage contacts 53 and 54. This closes a circuit including a, source of voltage and a wire to which a relay 5liv isconnected. The relay 55 is thus ener- I through a source or voltage, a wire 60, a second wire 6| to which a. switch 62 is connected, and a again assumes its intermediate position breaking the contacts 53 and 54 and thus de-energizing the relay 55. The armature 51 0f the relay 56. drops and engages contacts 55 and 58,, thus closling a circuit including the wire 60, a wire 51 to which a switch 68 is connected, and a second connection of the motor 63. 1 With the new connection, the motor 53 will nm in a reverse direction, thus closing the valve 64 and'stopping the flow of solvent into the ink supply.= The switch 53 is provided to stop the motor as soon as the valve 64 is completely closed, and is operated by the valve stem as will be described :later.

It now the intensity of the color of the ink becomes too light, the magnetomotive force due to the increased plate current flowing through the main winding of the relay44 dominates, so

' age is fed to the photo-sensitive tube circuit,

'Ireversible motor 63 which is thus placed in op eration. The shaft of the reversible motor 53 is connected 'to the stem of the gate valve 64 which "controls the flow of solvent to the ink supply. I Thus the closure of the upper contacts of the re- .lay 5'! acts to operate the motor and open the valve t4, thereby adding solvent tothe ink mixture, and causing itto become lighter in color intensity. The switch 62 acts to stop the motor when the valve 64 is completely opened as will be described later. 7 v When the intensity of color of theink has become normal, the armature 5| of the relay 44 that its armature 5| is forced upwardly against the tension of the spring 52 to engage contacts 53' and 54'. A circuit is closed thereby in lllding or a wire 55, a relay 55*' and a source of voltage by means of which the relay 56' is energized. The armature 51' of the relay 56' then rises engaging contacts 58' and 59, thereby closing a circuit including a source of' voltage, the wires 60' and 5| a switch 52 and a reversible motor 53". The motor 63' is then put into operation opening a valve 54' which controls the flow of ink to the ink supply. When the valve 54' is completely opened, the motor is shut oil by means of the switch 62' as will'be described later.

. After suflicient ink has been added to the ink supp y to bring it back to its normal color intensity, the armatur 5| once more resumes its intermediate position thus de-energizing the 'r lay 56'. Its armature 51' then' drops, breaking the contacts 58' and 59' and engaging contacts 55" and 55'. A circuit is closed thereby including a source of voltage, wires 60' and 61', a switch 68' and a second connection on the motor 53'. With this second connection the motor 63' is caused to rotate in the reverse direction, so that the valve 84' is closed and ink is no longer fed to the ink supp y. When the valve G4" -complete1y,.closed, th motor 53' is shut off by means of the switch 60' as will beshownlater;

As indicated in Figure 2 the ink system comprises an ink storage tank 69 connected to the supply tank 12 through a pipe H in which there incatFii-istfisuwated bfthe reversing motor 63' not shown. A solvent storage tank I3 is likewise connected to the supply tank 12- by means of a pipe in which there is connected the motor driven valve 54. The mixture oi' ink vent in the supply m1: is circulated by means of a pump 15 through a pipe", the inkfountain "and back to thesupp y tank I2- through a tube in the pipe 16- where it registers any changes in the intensity of color of the ink and brings the color intensity back, to normal by automatically opera i er otethe valvesjgggmgx Reference has been made above ahanism by means of which the motors 63 and 53' may be shut down when the valves 54 or 54' respectively are completely opened or completely. closed. It comprises the reversible motor 63 and its shaft 18 on which'a pin I9 is formed. The pin I9 is adapted to be received slidably in a spiral groove 80 formed in a coupling member 8| which is splined to the stem 53 of the valve 64.

On the coupling member 8| is secured a flange 82 which is adapted to engage the elements of the switches 521and58 inthe wires 5| and 51 respectively. When the valve 54 opened,'its

. a lens to focus the light from the said lightspindle 8i moves axially outward, moving the flange 82 in a corresponding manner. The switch '62 is so disposed that when the valve 64 is completely opened the flange 82 engages the contactmeans, a photo-sensitive cell. responsive to variations ofintensity of the said focused light, a

narily result on operation of the motor beyond the limits set by the valve stops is avoided.

The device instantaneously registers any changes in the color intensity of the ink fed to the ink fountain, and thereupon automatically causes either ink or solvent'to be fed thereto for the purpose of preserving a desired color in tensity of ink. As a result of this invention ink of constant color intensity may be readily obtained over long periods of operation, with a minimum of supervision.

It is evident that the mechanism herein disclosed is capable of considerable modification pipe to supply ink to the said ink fountain, a

second pipe to supply solvent to the said ink' fountain, a valve in each of the said pipes, a reversible electric motor on each of the said valves, circuits for each of the said motors in-' cluding the contacts of a relay, a circuit for each of the said motor relays including the contacts of a third relay, a circuit for the said last relay, and means actuated by the said photosensitive cell to energize the circuit,of the last relay.

3. A color intensity control device in inking mechanisms for printing presses comprising an ink fountain, light means sensitive to variations I of the color intensity of the ink supplied to the ink fountain, a lens to focus light from the said light means, a photo-sensitive cell responsive to variations of intensity of the said focused light, a pipe to supply ink to the said ink fountain, a second pipe to supply solvent to the said ink fountain, a valve in each of the said feed pipes, a reversible electric motor on each of the said valves, circuits for each of the said motors including the contacts of a relay, a circuit for within the scope of the invention. For-example,

the control of the intensity of the ink color need.

not be efiected by directing light through the transparent ink chamber, but maybe accomplished through light reflection from the body of ink. In this case only one transparent wall is necessary in the ink chamber, and light may appropriate optical system. The light reflected from the body of the ink in the ink chamber then serves to indicate changes in the color intensity of the ink.

As a further modification', light of a complementary color may be directed through the ink, thus dispensing with the color intensity filter on the color control device.

Inasmuch as, in commercial printing operations, an ingredient known as extender is used as well as solvent to maintain a. desired uniformity of tone strength, it is understood that this j invention contemplates such use, and, if desired,

the addition of the extender may be controlled as well as the solvent by means of this invention. Since additional modifications are possible, it

is to be understoodthat the above specification is presented only as descriptive of the invention, and the latter is to be in no way' limited thereb save as'deflned in the appended claims. a

" I claim:

1. A color intensity control device in inkingmechanisms for printing presses comprising an ink fountain, light means sensitive to variations of, the color intensity of the ink supplied to the said ink fountain, a lens to focus the light from the said light means, a photo-sensitive cell'responsive to the said focused light, a pipe to supply ink to the ink fountain, a second pi to each of the said pipesg a reversible electric motor on each of the said valves, circuits for each of the said motors, and means actuated by the said photo-sensitive cell to energize'the said motor circuits.

2. A color intensity controldevice n inkin mechanisms for printing presses comprising an ink fountain, light means sensitive to the color intensity. of the ink supplied to the ink fountain,

- be supplied from a source in conjunction with an each .of the said motor relays including the contacts of a third polarized relay, a circuit for the said polarized relay including the plate of a thyratron tube, the said thyratron tube beingactuated by the said,photo-sensitive cell. 4. A control device in inking mechanisms for printing presses comprising an ink fountain,

means sensitive to the intensity of the color of the ink supplied'to the ink fountain, a pipe to supply ink to the ink fountain, a second pipe .to supply solvent to the ink fountain, a valve in each of the said pipes, reversible electric motors connected to the respective valves to open and close the same, circuits for each of'the said motors, means actuated by the motors to break the said circuits for the said motors when the valves are open or closed, means, actuated by the means sensitive to the color intensity of the ink for energizing the said circuits. I

5. A control device in inking mechanisms for printing presses comprising an ink fountain,

light means sensitive to the intensity of the color of the ink supplied to the ink fountain,-a lens to focus light from the said light means,

7 a photo-sensitive cell responsive to variations of the intensity of the said focused light, a feed pipe to supply inkto the said, ink fountain, a"

second pipe to supply solvent to the said ink I fountain, a valve vin each of the said pipes, re-

- supply solvent to the ink fountain, 'a valve in versible electric motors connected to the respective valves to open and close the same, circuits .for the said motors, a pluralityof switches in the said-circuits to shutoff thesaid motors,

means associated withthe said valves and actuatedby said motors to operate the said switches whenthe valves are closed or open, w and means actuated by the said photo-sensitive. cell to energize the said circuits selectively to open and close said switches.

s 6. A method of controlling the color intensity of inks used ln'the inking-systems of printing presses, which consists in directing a light beam 1 tothe ink to cause a first Iightbeam to be emitted therefrom and directed to a desired viewing position; utilizing the characteristic color of the ink; as a complementary color to cause theilighti at the viewing position to lack color but be of a discernible intensity, directing of no characteristic color to the viewing position and adjacent the aforesaid light, viewing the first light and the second light of standard intensity. and controlling the supply of ink in gredients upon variation of. such light intensity to maintain substantially equal intensitiesoi the said first light beam and the standard light beam,- whereby a-desired intensity of color of the ink is maintained. v 7. In a method of controlling the color intensity of ink used in inking systems or printing presses, the steps of directing light of pre-'v -4 r *c gezms a a second light beamof standardintensit'y but determined intensity through theink, passing the resulting rays through a filter of a color complementary .to the desired color of the ink, the density of the filter being such that light free 5 from the color of the ink and of discernible intensity is transmitted when the ink is of desired intensity of color, directing light of a standard intensity and neutral color adjacent said filtered A light 'rays, and viewing the latter in comparison 10 with the light raysoi standard intensity'to aso certain deviations of the color intensity from the chosen standard of intensity.

FREDERICK M. BENDER;

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