Electronic Control System For Adjustment Of Ink Fountain In A Printing Press

Abstract

An electronic system for adjusting the ink fountain in a printing press. The ink fountain includes a plurality of adjusting screws driven by a motor through a drive shaft which is clutched and declutched to the screws by means of a solenoid matrix. Energization of selected solenoids within the matrix is controlled by pushbuttons on a unit control panel. A first series of buttons is used to select the plate position at which the adjustment is to be effected, and a second series of pushbuttons is used to select the column position at which the adjustment is to be effected. A pair of separate unit control panels is provided at each printing unit in the press. A digital counter provides a visible indication of the magnitude of each adjustment commanded by the operator. The system may be used for presetting the press, as well as making adjustments during a press run. A color cylinder or half deck on the unit may be controlled through the same control panel used to control the balance of the unit.

Description

DESCRIPTION OF THE INVENTION

The present invention relates generally to an electronic system for adjusting the ink fountain in a printing press and, more particularly, to such a system which permits virtually any desired adjustment to be made by operation of a few simple pushbuttons.

It is a primary object of the present invention to provide an electronic control system which permits the ink fountain in any given unit of a printing press to be automatically adjusted by selected operation of a bank of pushbuttons at a single conveniently located control panel.

It is another object of the invention to provide an electronic control system of the foregoing type which is capable of presetting the press as well as making adjustments during a press run.

A further object of the invention is to provide an electronic control system of the type described above which provides the operator with an instantaneous visible indication of the magnitude of each commanded adjustment.

Yet another object of the invention is to provide such an electronic control system which permits adjustment of different points in the ink fountain separately or in any desired combination.

A still further object of the invention is to provide such an electronic control system which provides extremely reliable operation at a relatively low cost.

It is a still further object of the invention to provide such an electronic control system which can be efficiently manufactured and maintained.

Other objects and advantages of the invention will become apparent from the following detailed description taken in conjunction with the attached drawings, in which:

FIG. 1 is a schematic block diagram of an electronic control system embodying the invention;

FIG. 2 is a perspective view of a control panel for use with the system illustrated in FIG. 1;

FIG. 3 is a more detailed schematic diagram of the unit control matrix included in the system of FIG. 1;

FIG. 4 is a more detailed schematic diagram one potion of the system of FIG. 1;

FIG. 5 is a more detailed schematic diagram of another portion of the system of FIG. 1; and

FIG. 6 is a more detailed schematic diagram of still another portion of the system of FIG. 1.

While the invention will be described in connection with one particular embodiment, it is to be understood that it is not intended to limit the invention to any particular embodiment. To the contrary, the intention is to cover all alternatives, modifications and equivalents falling within the spirit and scope of the invention.

It is well known by those familiar with the art of printing presses that a printing press of the type used to print newspapers comprises a series of printing units for printing the various pages of the newspaper, and at least one folding unit for receiving the printed pages and folding them to form the newspapers. Each printing unit includes at least one "printing couple," and typically from two to four "printing couples," depending upon whether it has a single color deck, a double color deck, or no color deck at all; each printing couple has a plate cylinder which is typically four pages wide and two pages around so that it is capable of printing eight pages, although it is to be understood that the present invention is applicable to printing couples having virtually any number of pages along its width and/or around its circumference. If a printing cylinder has a four-page width, it is generally considered to have four "plate positions," although the cylinder is actually capable of receiving eight or more printing plates, i.e., two or more at each plate position. The four plate positions are generally identified as "near," "near center," "far center" and "far."

For the purpose of supplying ink to the printing rolls, each printing cylinder is normally associated with an ink fountain having an adjustable means for controlling the rate at which ink is supplied. To permit adjustment of the ink supply rate, the adjustable means is typically provided with a number of separate adjusting stations spaced along the length of the cylinder. As is well known to those familiar with the press art, both blade type and injector or pump type ink supply systems are conventionally used with printing presses, and the present invention is equally applicable to any of these systems.

The illustrative system is designed for use with a fountain adjusting mechanism of the type described in U.S. Pat. No. 2,572,554 to E. M. Worthington, but it will be understood that the invention is equally applicable to any other type of adjusting means that is capable of being controlled by electrical signals. In the system described in the aforementioned patent, blade adjusting screws are advanced or retracted, to adjust the flexure of the fountain blade, by means of a drive shaft which is coupled to selected adjusting screws by actuating solenoids associated with the respective screws. When the shaft is rotated in one direction, any adjusting screws coupled thereto are advanced during the interval that the actuating solenoids are energized; when the shaft is rotated in the opposite direction, the actuated adjusting screws are retracted during the interval that the solenoids are energized.

In FIG. 3, 51a, 51b, 51c and 51d represent the actuating solenoids associated with the adjusting screws at the column positions at each of the plate positions for a printing cylinder in one printing unit. More particularly, the four solenoids 51a-51d actuate the "far," "far center," "near center," and "near" adjusting screws, respectively, associated with one printing cylinder at the first column position. In other words, the vertical position of any given solenoid in the illustrative solenoid matrix determines the printing cylinder and the plate position, while the horizontal position determines the column position. Although the illustrative solenoid matrix is for only one printing cylinder having nine column positions, it will be understood that any desired number of solenoids may be provided to control a corresponding number of adjusting screws in different types of printing units, i.e., having different numbers of printing cylinders and/or column positions.

In accordance with the present invention, the fountain adjusting screws are driven by a reversible electric motor controlled by an electronic control system which includes manually actuated signal generators for producing electrical signals representing selected plate and column positions in the press. Thus, in the illustrative system of FIG. 1, a reversible electric motor 20 is connected to the drive shaft (not shown) which turns the adjusting screws in the conventional ink fountain adjusting mechanism.

Selection of the particular plate and column positions at which the ink fountain is to be adjusted is effected by operation of a series of individual page operators 21 (FIG. 1) and a series of individual column operators 22. In the illustrative system, the page operators 21 are in the form of pushbutton-operated switches 21a, 21b, 21c and 21d (FIG. 2) located on a unit control panel 23 which may be situated either in the press room or at a remote location. By depressing selected ones of these pushbuttons 21a-21d, the operator may command an adjustment in the ink fountain at any of the four corresponding plate positions, i.e., far side (button 21a), far center (button 21b), near center (button 21c) or near side (button 21d).

The individual column operators 22 in the illustrative arrangement are in the form of two additional rows of pushbutton-operated switches 22a through 22t, all of which are located on the control panel 23 directly below the pushbuttons 21a-21d. By depressing selected ones of the pushbuttons 22a through 22i, the operator may command an increase in the ink supply rate at any one of the corresponding nine column positions at the selected plat positions; or by depressing the pushbutton 22j the operator may command an increase in the ink supply rate at all nine column positions simultaneously. Similarly, by depressing selected ones of the pushbuttons 22k through 22s, the operator may command a decrease in the ink supply rate at any one of the corresponding nine column positions at the selected plate positions; or by depressing pushbutton 22t the operator may command a decrease in the ink supply rate at all nine column positions simultaneously. Thus it can be seen that the horizontal position of the selected pushbutton determines the column position at which the change is to be effected, while the vertical position of the selected pushbutton determines the direction of the change to be effected.

Returning to FIG. 1 for a more detailed discussion of the control system associated with the operators 21 and 22, the page operators 21 are momentary operated switches connected to a "unit page selection" circuit 29. The circuit 29, which will be described in more detail below, responds to the actuation of any one of the operators 21 to actuate a "page driver" 29a which supplies enabling signals to the solenoid matrix for the particular press unit being controlled; this solenoid matrix is identified in FIG. 1 as the "unit coil matrix" 24. These signals are transmitted from the unit page operators 21 to the unit coil matrix 24 via four lines 25, 26, 27 and 28 which correspond to the four plate positions represented by the four pushbuttons 21a through 21d, respectively. It can be seen from FIG. 3 that a signal on any one of the four lines 25 through 28 enables all nine solenoids at the particular plate position represented by such signal. For example, an enabling signal on the line 25 enables all nine solenoids 51a-59a associated with the "far side" plate position.

Selection of the particular column positions at which the ink fountain is to be adjusted is effected by the individual column operators 22. For example, if the operator depresses pushbutton 21a, the resulting signal transmitted via line 25 enables all nine solenoids associated with the "far side" plate position, but any given solenoid within that group is not energized unless and until the operator also depresses one of the pushbuttons 22a-22t: When the operator depresses one of the pushbuttons 22, the corresponding solenoid is then energized so as to clutch the corresponding adjusting screw in the ink fountain to the drive motor. For example, if the operator depresses page button 21a and then column button 22a, the solenoid 51a is energized to clutch the corresponding adjusting screw, i.e., at the first column position at the "far side" plate position, to the drive motor. As mentioned previously, the clutching mechanism is described in more detail in the Worthington U.S. Pat. No. 2,572,554.

For the purpose of energizing the drive motor 20, the individual column operators also are connected to a motor reversing circuit 30. As mentioned previously, the top row of column pushbuttons 22a through 22j is used to increase the ink supply rate, while the lower row of column pushbuttons 22h through 22t is used to decrease the ink supply rate. Thus, if one of the "increase" buttons 22a-22j is depressed, a signal is transmitted to the motor reversing circuit 30 which energizes the drive motor 20 to turn the ink fountain adjusting screws in the direction required to increase the ink supply rate. Similarly, if the operator depresses one of the "decrease" buttons 22k-22t, a signal is transmitted to the motor reversing circuit 30 which energizes the motor 20 to drive the adjusting screws in the opposite direction, i.e., in the direction required to decrease the ink supply rate. To enable the operator to adjust all the column positions simultaneously, the "increase" row of pushbuttons includes an "all" column button 22j, and the "decrease" row of pushbuttons includes an "all" column button 22t. These "all" column buttons are indicated generally as an "all" column operator 72 in FIG. 1.

As long as the operator holds one of the individual column operators 22 depressed, the drive motor 20 continues to turn the adjusting screws at the selected plate and column positions. In other words, the magnitude of the adjustment commanded by the operator is determined by the length of time that he holds the individual column operators 22 depressed.

In accordance with a further aspect of the present invention, an electronic counter responds to any adjustment of the ink fountain to provide a continuous and instantaneous indication of the magnitude of the adjustment effected in response to any given command by the operator. Thus, in the illustrative system, actuation of any one of the individual column operators 22 sends an enabling signal via line 31 to a gate 32, thereby transmitting a train of constant frequency pulses from a source 33 to a digital counter 34. As long as one of the individual column operators 22 remains depressed, the gate 32 remains open, and the pulses are supplied continuously to the counter 34. The counter 34 counts the input pulses continuously, and supplies a corresponding output signal to a conventional numeric readout indicator 35 which is mounted on the main control panel 23 (FIG. 2) to provide the operator with a continuous numeric indication of the magnitude of the adjustment that has been effected at any given instant.

As mentioned previously, the page pushbuttons 21a-21d are only momentary-operated, while the column pushbuttons 22a-22t must be held in the depressed position by the operator, since it is the length of time that the column pushbuttons are depressed that determines the magnitude of the adjustment commanded by the operator. In order to provide the operator with a continuous indication of which page pushbuttons 21 have been operated, a series of page selection indicators 36 respond to the operation of any given page pushbutton 21a-21d to provide the operator with a continuing indication of which pushbutton has been operated. For example, the page selection indicators 36 may be in the form of lights to illuminate the particular pushbuttons 21a-21d that have been operated.

When a color cylinder or half deck is included in the particular printing unit being controlled by the illustrative system, a second set of page operators, designated the "color cylinder" page operators 40, are provided on the control panel 23. This second set of page pushbuttons is not included in the exemplary control panel 23 shown in FIG. 2, but is schematically illustrated in FIG. 1. As in the case of the unit page operators 21, a color "cylinder page selection" circuit 41 responds to depression of any one of the operators 40 to actuate a color cylinder selection indicator 42 to provide the operator with a continuous indication of the particular color pages that have been selected. The color cylinder page selector 41 also actuates a page driver 43 which supplies enabling signals to a color coil matrix 44 which is identical to the unit coil matrix 24 previously described. The matrix 44 is also controlled by the same individual column operators 22 which control the unit coil matrix 24, and in exactly the same manner.

For the purpose of disabling the unit page operators 21 whenever a color page cylinder operator 40 is operated, and vice versa, the two control systems are interconnected by a unit and color cylinder interlock 45. This interlock 45 disables the unit page operators 21 whenever a color page operator 40 is actuated, and, similarly, disables the color cylinder page operators 40 whenever a unit page operator 21 is actuated.

To drive the adjusting screws associated with the link fountain for the color cylinder, a second drive motor 46 is connected to the motor reversing circuit 30. This second drive motor 46 is controlled by the circuit 30 in exactly the same manner as the motor 20 previously, i.e., in response to actuation of the individual column operators 22.

Turning now to FIG. 4 for a more detailed description of the control system which interconnects the page and column operators with the solenoid matrix, depression of the page pushbutton 21d closes a normally open switch SW1. While the switch SW1 is open, resistors R1, R2, and R3 form a potential divider across a supply voltage V1, thereby providing the base drive for a transistor Q1, and a charging path for a capacitor C1. The capacitor C1 charges to a predetermined level, and the transistor Q1 is rendered conductive as soon as there is sufficient base current to provide a low voltage (referred to hereinafter simply as "a low") at the collector of the transistor Q1.

Upon the closing of switch SW1, the capacitor C1 discharges through a resistor R14, thereby rendering the transistor Q1 nonconductive. The collector of the transistor Q1 then presents a high voltage (referred to hereinafter singly as "a high") to one of the inputs to a gate G1 which is a logic AND gate. The other input to the gate G1 is normally the potential of V4 (high) but resistor R13 causes the input to be an active low whenever gate G7 is active. The output of the gate G1 is normally high, but upon presentation of the high input from the transistor Q1, the output of the gate G1 changes to a low. The output of the gate G1 is fed to a gate G2 which cooperates with a gate G3 to form a bistable latch, with the output of gate G2 being normally low. When the output from gate G1 produces a low input to G2, the gate G2 produces a high output, thereby producing a low at the output of gate G3. The output of gate G3 is connected to the input of gate G2, thereby latching the high on the output of gate G2.

The high output from gate G2 provides the base current for a transistor Q2 via resistor R6 and diode D1, thereby rendering the transistor Q2 conductive to energize the coil of a relay CR1. Energization of the relay CR1 closes a first pair of contacts CR1a connected to the gate of a Triac Q11 (a gate-controlled full-wave AC silicon switch designed to switch from a blocking state to a conducting state for either polarity of applied voltage with positive or negative gate triggering) which provides the ground return for the coils 51a-59a (FIG. 3) in the first plate position of the solenoid matrix 24, thereby conditioning these coils for energization.

In accordance with one particular aspect of the invention, the bistable latch is always reset in response to actuation of a unit page operator 21 other than the particular operator associated with the switch SW1, i.e., other than pushbutton 21d. Thus, in the illustrative system, a gate G4 is provided to reset the latch if a unit page operator other than 21d is actuated. More particularly, one of the inputs to the gate G4 is from the output of gate G1, and is normally high; the other input to the gate G4 is normally low and goes high for a period equal to the length of a reset pulse generated by circuitry to be described in more detail below. Since the output of the gate G1 is low when the switch SW1 is momentarily closed, the reset pulse does not change the state of the gate G4. However, if the switch SW1 is not closed, the output of the gate G4 will go low for a preselected time interval, thereby resetting the latch to its normal condition.

For the purpose of providing the operator with a continuing indication of the particular page that has been selected, after the momentary-operated pushbutton 21d is released, energization of the coil of relay CR1 also closes a second pair of contacts CR1b. The closing of these contacts CR1b energizes an indicator light L1, preferably mounted within the pushbutton 21d, to illuminate the same from a voltage source V3 via resistor R7. Of course, when the bistable latch is reset, as described above, the indicator light L1 is turned off due to the opening of the contacts CR1b in response to deenergization of the relay CR1.

The circuitry described thus far is all associated with only one specific page operator, namely pushbutton 21d. It will be appreciated that similar circuitry is associated with each of the other three unit page operators 21a-21c, and also with each of the four color cylinder page operators 40. More specifically, the gates G1', G1", and G1'" in FIG. 4 are each associated with circuitry identical to that described above for the gate G1. Similarly, each of the gates G1a, G1a', G1a", and G1a'", which are associated with the four color cylinder page operators 40, is also associated with circuitry identical to that described above in connection with the gate G1.

In order to provide an interlock between the unit page operators 21 and the color cylinder page operators 40 (FIG. 1), the output from the gate G1 is connected to a gate G5. When all the unit page operators 21 are released, a high is presented on each of the inputs to the gate G5 from gates G1-G1'", thereby producing a low at the output of gate G5. This output is supplied to a gate G6, which is connected as an inverter to provide a high input to a gate G7. When one of the unit page operators 21 is actuated, the output from gate G6 changes from high to low, thereby providing a low input to each of the color cylinder gates G1a-G1a'" to disable all such gates.

Similarly, the outputs from each of the gates G1a through G1a'" are supplied to a gate G8, the output of which is supplied to a gate G9, which in turn is connected as an input to each of the gates G1 through G1'" to disable the latter gates whenever one of the color cylinder page operators 40 is actuated. The output from the gate G9 is also supplied to the same gate G7 which receives the output from gate G6 associated with the unit page operator gate G1-G1'". Of course the purpose of this interlock function is to limit the control of the column operators 22 to only one ink fountain at a time. That is, the interlock insures that operation of the column operators 22 controls ink fountain adjustments only at either the main unit cylinder or the color cylinder, but not both at the same time.

Before any page operators 21 or 40 are actuated, the gate G7 normally has a high on both of its inputs, thereby providing a low output. This low output holds a transistor Q3 in an off condition, while transistor Q4 receives its base current through a resistor R10 and is turned on. A capacitor C2 connected between transistors Q3 and Q4 is in a charged state, having been charged through resistor R11 and the base-emitter junction of transistor Q4. When a page operator is actuated, the low on the output of gate G6 appears at the input to the gate G7, thereby providing a high at the output of gate G7 to turn the transistor Q3 on. When transistor Q3 turns on, the capacitor C2 discharges through the collector-emitter junction of the transistor Q3, thereby pulling the base of the transistor Q4 low to turn off the transistor Q4. After the capacitor C2 is discharged sufficiently to allow the transistor Q4 to draw a suitable base current, the transistor Q4 is turned on again. Thus, the collector of the transistor Q4 produces a reset pulse, the width of which is determined by the value of capacitor C4 and is typically of 7 milliseconds duration, each time a page operator 21 or 40 is depressed. This reset pulse is supplied to the input of gate G4 via gates G10 and G11 which are connected as inverters and provide the necessary interface between the transistor Q4 and the bistable latch associated with gate G4. Of course, this same pulse is also supplied to the counterparts of gate G4 in the circuits associated with the other page operators, e.g., 21a, 21b, 21c (not shown in FIG. 4). Accordingly, it can be seen that the latching arrangement associated with any operator that is not actuated automatically receives a reset pulse which deactivates the circuitry associated with that particular operator.

Turning next to FIG. 5, the circuitry associated with the individual column operators 22 will be described in more detail. Actuation of one of the "increase" column pushbuttons 22a-22i closes a normally open switch SW2, while actuation of one of the "decrease" column pushbuttons 22k-22s closes a normally open switch SW3. While the switches SW2 and SW3 are both open, resistors R17, R9 and R18 form a voltage divider across a supply voltage V5, thereby providing base current for a transistor Q5 to turn the transistor on and thereby provide a low at the collector of the transistor Q5. Three parallel input diodes D1, D2, and D3 in combination with the resistor R17 form an AND gate to the base of the transistor Q5. A ground on any one of the input diodes D1-D3, due to the closing of switch SW2 or SW3 for example, discharges a capacitor C3 and thereby turns off the transistor Q5, allowing the output of the transistor Q5 to go high. The capacitor C3 has a relatively fast discharge rate as controlled by resistor R8, and a slow charge rate as controlled by resistor R17, and thus effectively eliminates incorrect operation due to contact bounce on the contacts of the switches SW2 and SW3.

As long as the transistor Q5 has a low output, a transistor Q6 connected thereto is normally held in a non-conductive state, and a transistor Q7 is normally held on by a base resistor R15. In this operative state, a capacitor C4 connected between the two transistors Q6 and Q7 is in a charged, having been charged through resistor R14 and the base-emitter junction of Q7. When the output of the transistor Q5 goes high, in response to actuation of one of the switches SW2 or SW3, the transistor Q6 is rendered conductive, and capacitor C4 discharges through the collector-emitter junction of Q6, pulling the base of transistor Q7 low to render the transistor Q7 non-conductive. After the capacitor C4 is sufficiently discharged to allow the transistor Q7 to draw a suitable base current, the transistor Q7 turns on. Thus, the collector of the transistor Q7 provides a reset pulse; the width of the rest pulse being determined by the value of capacitor C4, and is typically about 7 to 9 milliseconds.

Still referring to FIG. 5, the constant frequency pulse train from the pulse source 33 and the gate 32 is applied to the base of a transistor Q8 via resistor R11. This signal is typically sinusoidal, and about 5 to 8 volts peak-to-peak. The transistor Q8 is operated as a saturated switching transistor, giving a square wave output at its collector, and it also acts as an interface buffer for the integrated circuits which are preferably used as the gating devices. The output from the transistor Q8 is applied to one input of a two-input NAND gate G12, which receives its other input from the transistor Q5 in response to the closing of switch SW2 or SW3, i.e., in response to actuation of one of the column operator buttons 22. When the gate G12 is thus enabled, the square wave present on the collector of the transistor Q8 appears inverted at the output of the gate G12, and it is this square wave which presents the successive pulses to be counted by the binary counter BC1.

In order to remove steps in the rise and fall times of the square wave output from the gate G12, a feedback signal is supplied from the output of the gate G12 to the base of the transistor Q8 via a resistor R13. This feedback is necessary to provide a quick fall time at the input to the binary counter BC1. Gates G13, G14 and G15 connected between the output of the gate G12 and the input to the counter BC1 provide further shaping of the fall time of the signal. The counter BC1 counts when the count signal changes from high to low.

It will be noted that an additional input is available on the gate G13, for use in the manual preset mode to be described in more detail below.

For the purpose of resetting the counter BC1, the reset pulse from the transistor Q7, described previously, is supplied via gate G16 to a gate G18, which is a NAND gate receiving its other input from a bistable latch to be described below. The output of the gate G18 is fed through a gate G19, which is connected as an inverter, to the counter BC1. If either of the inputs to the gate G18 goes low, then the counter BC1 is reset to zero, putting a low on each of the counter outputs 51, 52 and 53. These counter outputs are connected to a gate G20, which is normally high and goes low when the count reaches a preselected number, e.g., 13. The output of the gate G20 is connected to a pair of gates G21 and G22 which form a bistable latch. When the output of the gate G20 goes low, the output of the gate G21, which is normally high, is forced low. Consequently, a low is provided on the reset terminal of the counter BC1 through gates G18 and G19, thereby setting the binary counter BC1 to zero and returning the output of the gate G20 to a high. It will be appreciated that the counter BC1 is thus cyclically reset so that it counts the preselected number, e.g., 13, repetitively as long as it receives input pulses from the gates G12, G13, G14 and G15.

The latch formed by the gates G21 and G22 is reset whenever the count pulse to the input of the counter BC1 goes high, thereby removing the reset condition from the counter BC1. The output from the gate G21 is also connected to the input to a second binary counter BC2, which receives a count pulse each time the count on the counter BC1 reaches 13. The counter BC2 is a divide-by-ten counter with its output connected to the input of a third divide-by-ten binary counter BC3. Thus, the counter BC2 is a "units" counter, and the counter BC3 is a "tens" counter.

In order to convert the outputs from the binary counters BC2 and BC3 to appropriate input signals for corresponding "units" and "tens" numeric readout units 54 and 55, respectively, the outputs from the two counters BC2 and BC3 are fed to two corresponding drivers 56 and 57, respectively, which decode the signals from the counters BC2 and BC3 to drive the readout units 54 and 55 to provide a continuous display of the instantaneous count on the main control panel 23. The output signals from the counters BC2 and BC3 are also applied to the manual preset circuit to be described below.

As was mentioned previously, the illustrative control system of FIG. 1 can be used to preset the ink fountain as well as to make adjustments during a press run. More particularly, selection of the particular plate positions at which the ink fountain is to be preset is effected by operation of the same page operators 21 and/or 40 described previously. The magnitude of the presetting adjustment to be effected at any given plate position is effected by operation of a preset selector 47, which may take the form of decade switches which set a binary code on one of the sets of inputs to a comparator 48. The output signal from the comparator 48 operates set and reset latches indicated generally at 49 in FIG. 1, and these latches are also controlled by a preset start operator 50. When the preset start operator 50 is actuated, the latches 49 actuate the "all" column operator 72 and at the same time cause the motors 20 and 46 to be driven, via the motor reversing circuit 30, to return the ink fountains to the zero position. After the fountains have thus been reset, the latches 49 automatically start to open the fountains. The latches 49 also actuate a start/stop gate 71 to reset the counter 34 to zero, while a hold count circuit 70 stops the counter 34 from operating during the reset interval. After a predetermined time interval, which is selected to allow time for the ink fountain to close at all column positions, the set latch portion of the latches 49 reverses the direction of the motors 20 and 46, terminates the hold count signal from the circuit 70, and starts operation of the digital counter 34 via gate 71.

In order to terminate the presetting operation when the counter 34 registers a count corresponding to the preset count entered at the selector 47, the counter 34 supplies a second input to the comparator 48. When the count registered by the counter 34 is identical to the preset count selected at 47, the comparator 48 generates an output signal to the latches 49 to deactuate the "all" column operator 72 and to terminate operation of the drive motors 20 and 46. The count accumulated by the counter 34 is indicated to the operator on the indicator 35 in the same manner as described previously for an adjustment effected during a press run. When the presetting operation has been completed, of course, the count indicated on the indicator 35 is identical to the preset number entered at the selector 47.

Turning next to FIG. 6 for a more detailed description of the manual preset system, a reset circuit is connected to the power on-off switch to insure that the latches 49 have the correct relationships. This is necessary because when the equipment is turned on, the latching elements in certain parts of the circuit assume random positions, and conditions can be such that the coils of FIG. 3 are given an erroneous counting sequence. Thus, in FIG. 6, turning on the power to the system renders a transistor Q20 conductive due to an apparent short circuit across a capacitor C10. The transistor Q20 is an emitter follower associated with a transistor Q21 which is a common emitter DC-coupled stage which follows the transistor Q20 so that the collector of the transistor Q21 goes low. Consequently, the capacitor C10 charges through resistors R20 and R21, and the base current of the transistor Q20 is gradually reduced to the point where the transistor Q20 is turned off. This deprives the transistor Q21 of its base current, so that the transistor Q21 is rendered non-conductive, to provide a high at the collector of transistor Q21. Thus, a low reset pulse is produced at the collector of the transistor Q21, with the duration of the pulse depending upon the time constant of the RC circuit formed by the capacitor C10 and the resistors R20 and R21; a typical time period for the reset pulse is about 15 milliseconds. This reset pulse is applied, via amplifying gate G33, to gates G13 and G18 and counters BC2 and BC3 in FIG. 5, as well as to gates G21 and G23 in FIG. 6.

When the power is turned on, the low signal supplied to gate G21 sets the "set" latch formed by the combination of gates G21 and G22. The setting of the "set" latch puts a high on the output of the gate G21 and a low on the output of the gate G22 so as to insure that the "set" circuit 60 is turned off, as will be described in more detail below. The low input to the gate G23 sets a "reset" latch formed by the combination of gates G23 and G24. The setting of this latch puts a high on the output of the gate G23 and a low on the output of gate G24 to insure that the "reset" circuit 61 is turned off, as will be described in more detail below.

The high on the output of the gate G23 also provides base current to a transistor Q23, thereby turning the transistor on to set a timer circuit 62 to its off condition, and insuring that a capacitor C12 is discharged. After a predetermined interval, such as 15 milliseconds for example, the output at the collector of the transistor Q21 goes high, returning the inputs to gates G21 and G23 to a high, but not changing the state of the bistable latches.

The system is now ready for depression of the "preset" start button 50 which closes the switch SW4 (FIG. 6). Before the switch SW4 is closed, a voltage divider formed by resistors R22, R25 and R24 provides the base drive for a transistor Q22, and a charging path for the capacitor C11. The capacitor C11 charges to a predetermined level, and the transistor Q22 is rendered conductive as soon as there is sufficient base current to provide a low voltage at the collector of the transistor Q1. When the "preset" start switch SW4 is closed in response to depression of the button 50, the collector of the transistor Q22 goes from low to high due to the discharge of capacitor C11 through resistor R23, thereby enabling a gate G20. That is, the transistor Q22 is turned off so that the input to the gate G20 changes from a low to a high; the other input to this gate is already high so that the output of the gate changes from high to low. The low output from the gate G20 is connected to a gate G24 and thus operates the "reset" latch so that the output of the gate G24 changes from low to high and thereby causes the output of gate G23 to change from high to low. The low output from the gate G23 turns off the transistor Q23 by removing its base current, and turns on a transistor Q24 via a gate G25. The turning on of the transistor Q24 energizes a "reset" relay CR12, thereby closing a first pair of relay contacts CR2a which actuate the motor reversing circuit 30 to energize the drive motors 20 and 46 to reset the ink fountain to the zero position. The closing of contacts CR2a also operates a slave relay via diode D4 to bypass the "all" column operator 72. The relay CR2 also closes a second pair of contacts CR2b, thereby grounding the diode D1 in FIG. 5 to operate that portion of the control system shown in FIG. 5 in the same manner as the closing of the switch SW2 or SW3, including resetting of the counter BC1 to zero. Finally, the closing of contacts CR2b also energizes a "reset" indicator light L2 mounted on the main control panel (FIG. 2).

Returning to the gate G23, the low on the output of this gate is applied to one of the inputs to gate G13, FIG. 5, to hold the count during the reset cycle. The low on the output of gate G23 is also applied to a gate G26 which prevents the set circuit 60 from operating. The low output of the gate G20 is applied to the gate G22 so as to change the output of the gate G22 from low to high. This high output is applied to the gate G26, although the gate G26 does not change state at this time due to the low on its other input from the gate G23. The high output from the gate G22 is also applied to the gate G21 and this input, together with the high on each of the other inputs to the gate G21, changes the state of the "set" latch. The output of the gate G21 is returned to the input terminal of the gate G20, thereby locking out further start pulses until the presetting action is completed. Although the operation of the latching circuits has been described in some detail herein, it will be understood that the operation of these circuits actually takes place in less than a millisecond in actual operation.

Turning next to the timer circuit 62, it will be recalled that this circuit was turned on when the transistor Q23 was turned off. More specifically, resistor R25, capacitor C12, and resistor R26 form an RC network with a preselected time constant, e.g., 80 seconds. The transistor Q23 is connected across the capacitor C12 so as to switch the timing circuit on and off, the capacitor C12 starts to charge. This increases the anode-to-cathode voltage across a programmable unijunction transistor Q25 having a gate which can be set to a predetermined voltage. When the anode-to-cathode voltage reaches a predetermined value, e.g., 0.5 volts positive with respect to the voltage on the gate, the transistor Q25 turns on and remains on until the capacitor C12 has been discharged through the resistor R26 and the anode-to-cathode junction of the transistor Q25. When this type of transistor turns on, the gate is pulled down to ground with the anode, and then returns to its original potential as soon as the capacitor C12 is discharged. The resistor R27 is used to set the time period for the timing circuit, and is typically set for 26 seconds. The gate of the transistor Q25 going low trips the reset latch formed by the gates G23 and G24, so that the output of the gate G23 goes high. At this point, the following events occur:

1. The high output from gate G23 puts a high on the input to gate G24 so that the output of gate G24 changes from high to low. The low output from the gate G24 is returned to the input of gate G23 so as to maintain the high output on gate G23.

2. The high output from gate G23 turns on the transistor Q23 so as to effectively turn off the timing circuit, so that it operates for only one time period.

3. The high output from gate G23 turns off the transistor Q24 via gate G25, thereby de-energizing the "reset" relay CR2 to open the contacts CR2a and CR2b, thereby stopping the resetting movement of the drive motors 20 and 46 and de-energizing the indicator light L2.

4. The high output from gate G23 applies a high input to gate G26 so as to change the state of the output from this gate from high to low.

5. The output from gate G23 releases the "hold count" signal supplied to gate G13, FIG. 5, so that the system starts counting in the "set" portion of the operation.

Turning now to the actual setting operation, the low output from the gate G26 changes the output of the gate G27 from low to high. This high output from gate G27 turns on a transistor Q26 so as to energize a "set" relay CR3. The energization of relay CR3 closes a first pair of relay contacts CR3a which actuate the motor reversing circuit 30 to energize the drive motors 20 and 46 to open the ink fountain. The contacts CR3a also maintain the enabling signal to the "all" column operator 72 (FIG. 1) via diode D5. A second pair of relay contacts CR3b closed by the energization of the relay CR3 maintains the enabling signal supplied to the diode D1 in FIG. 5, and also energizes a "set" indicator light L3 mounted adjacent the light L2 on the main control panel (FIG. 2).

For the purpose of selecting the preset count which determines the original setting of the ink fountain, i.e., the duration of operation of the motors 20 and 46 during the preset mode, the comparator 48 includes a "units" section 62 and a "tens" section 63. The "units" section is connected to a "units" decade switch 64 which is manually set so as to produce a binary coded decimal output to a series of four NAND gates G28a, G28b, G28c, and G28d, which may be included in a single intergrated circuit module. Each of these NAND gates is connected as an inverter, and the output from each gate is connected to the input of respective exclusive OR gates G29a, G29b, G29c and G29d, all of which may also be included in a single integrated circuit module. The other inputs to the OR gates G29a-G29d are derived from the output from the "units" numeric driver in FIG. 5, namely from the four output lines from the binary counter BC2.

The "tens" section 63 of the comparator 48 is connected to a "tens" decade switch 65 which is manually set to produce a binary coded decimal output to a series of four NAND gates G31a, G31b, G31c, and G31d, which may be included in a single integrated circuit module. Each of these NAND gates is connected an an inverter, and the output from each gate is connected to the input of respective exclusive OR gates G32a, G32b, G32c and G32d, all of which may also be included in a single integrated circuit module. The other inputs to the OR gates G32a-G32d are derived from the output from the "tens" numeric drive in FIG. 5, namely from the four output lines from the binary counter BC3.

When the inputs from the numeric drivers match the inputs from the gates G28a-G28d and G31a-G31d, the outputs from the gates G29a-G29d and G32a-G32d, respectively, cause a gate G30 to change from a high to a low output. This low output signal resets the latch formed by the gates G21 and G22 and stops any further movement of the drive motors 20 and 46. Of course, if the switches 64 and 65 are all set to zero, the fountain will simply be returned to its zero position, since the latch formed by the gates G21 and G22 is already reset.

Claims

I claim as my invention:

1. In an electrical ink control system for a printing press having a printing cylinder, a plurality of plate positions along the printing cylinder, a plurality of repeated columnar positions along each plate position, and control means for each columnar position along the printing cylinder to regulate the flow of ink from an ink supply to the respective columnar position, the improvement comprising:

means including a first manually-operated momentary enabling switch for each plate position along the printing cylinder for selecting the plate position at which ink regulation is to be effected;

means including a first manually-operated momentary activating switch for each repeated columnar position along a plate position for selecting the column position at which ink regulation is to be effected;

first matrix circuit means for selectively connecting each different combination comprised of one of said first momentary enabling switch means and one of said first momentary activating switch means in controlling relation to a different one of said ink flow regulating control means;

means including a first pulse activated bi-stable latch for connecting each of said first manually-operated momentary enabling switch means to said first matrix circuit means in enabling relation to all of said first manually-operated momentary activating switch means;

means for producing a pulse signal by manual operation of any selected one of said first enabling switch means to selectively set a respective one of said first bi-stable latch means in enabling relationship to all of said first activating switch means; and means generating a shorter duration pulse signal by the operation of any other of said first enabling switch means to reset said selected first bi-stable latch means in a disabled relationship to all of said first activating switch means.

2. The invention defined by claim 1 in combination with a printing press having an additional printing cylinder and corresponding plate positions, repeated columnar positions, and ink flow regulating control means, further comprising:

means including a second manually - operated momentary enabling switch for each plate position along the said additional printing cylinder for selecting the plate position at which ink regulation is to be effected;

means including a second manually - operated momentary activating switch for each repeated columnar position along the said additional corresponding plate position for selecting the column position at which ink regulation is to be effected;

second matrix circuit means for selectively connecting each different combination comprised of one of said second momentary enabling switch means and one of said second momentary activating switch means in controlling relation to a different one of said additional ink flow regulating control means;

means including a second pulse activated bi-stable latch for connecting each of said second manually-operated momentary enabling switch means to said second matrix circuit means in enabling relation to all of said second manually-operated momentary activating switch means;

means for producing a pulse signal by manual operation of any selected one of said second enabling switch means to selectively set a respective one of said second bi-stable latch means in enabling relationship to all of said second activating switch means; and means generating a shorter duration pulse signal by the operation of any other of said first and second enabling switch means to reset said selected second bi-stable latch means in a disabled relationship to all of said second activating switch means.

3. The invention defined by claim 2 wherein each said first bi-stable latch means also is reset by a shorter duration pulse signal generated by operation of any of said second manually-operated momentary enabling switch means.