JPS6127192B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to a computer-controlled printing method that uses the principles of non-impact inkjet printing to print variable message data on forms as well as fixed printing at high speeds. This makes it possible to print at high printing speeds.
The computer light printing method used to explain the present invention and proposed herein is a method that combines an office document printing device and a computer control device (or a direct mail advertising medium) and variable data input at the same time. This variable data reads addresses and other changing information from the magnetic tape.

The proposed computer light method provides a method capable of printing up to 1385 characters per second. At this speed, variable information consisting of dot matrix characters can be printed on a moving print medium at maximum printing speed. The computer light device shown here can be installed in a printing press without significantly reducing the efficiency of the machine currently in operation. For example, this computer lighting method uses flexible modular units. It can also be used for multiplex flexographic printing, which can produce prints of a wide range of sizes.

Flexo printing is a rotary type letterpress printing method that uses quick-drying volatile solvent ink and usually uses a flexible rubber printing plate. With the necessary ink distribution and the transfer method used with such inks, the printing plates are relatively cheap, the rollers are easy to clean, and it is easy to move from one operation to the next. Because of this, flexo printing differs from ordinary letterpress printing in that it has a conversion mechanism, making it particularly suitable for high-speed, low-cost, punch-in printing. The printing method can also be carried out economically within reasonable limits and without much waste. By placing the blank on printing cylinders of different diameters and changing the spacing on the cylinders, both length and width can be varied. This interchangeability of printing cylinders (and their dimensions) is what fundamentally differentiates flexographic printing from conventional rotary relief plate printing. Machine downtime is minimized because the print operator can prepare the procedure while other prints are being made.

Summary of the invention The main features of the present invention are as follows.

(1) It combines a high-speed inkjet printer and a high-speed rotary printing press (impact printer) in real time.

(2) At that time, by taking advantage of the characteristics of both printing machines,
Fixed data is transferred using a rotary press and an inkjet
An efficient printing method can be obtained by printing variable data using a printer.
(Figure 1) (3) In this case, the most important point that differs from conventional printing methods is that in an inkjet printer, the delay time from when an ink droplet receives a command to when it reaches the web must be taken into consideration. be. In other words, the distance the web moves must be calculated to match the time it takes for the ink droplet ejected from the nozzle to reach the web upon receiving the command (1.48 cm x 1/355.5 cm/s = 4.16 ms). Must not be. (Figure 2) (4) Therefore, it is necessary to know the web speed on the paper surface, and 2500 time measurement slots are provided on the master cylinder and this is used as a reference.

FIG. 3 shows the basic elements of the Computer Lite I inkjet printing system in block diagram form. Variable data information to be printed by the inkjet nozzle is placed on two magnetic tapes indicated by units 0 and 1 and stored in the magnetic tape unit 30, and the fixed format data to be printed by the original cylinder is stored in the magnetic tape unit 30. Print related information at the same time as fixed data. This variable data is arranged so as to be read out under the control of the computer 31.
Computer 31 distributes alphanumeric code character messages to computer interface 33. The computer 31 reads the data stored on the magnetic tape and the basic data controls and streams variable data inputs to the computer interface according to the program sequence. Computer 31 includes the necessary input/output systems and also includes data lines for communication between computer interface 33 and CRT operating control and display 32.

At a minimum, the CRT operating control and display 32 provides visible information to the system operator on a CRT display. It also has an associated keyboard, allowing the operator to interact with the computer to insert necessary data, and to input system data information necessary for Computer Lite I operation. The CRT display also serves to inform the operator of information generated by the computer in connection with the operation of the system.

Form position and print media web speed circuit 34
the required form dimensions, print media web speed,
and provides data related to the rotation rate of the printing main cylinder. This includes the necessary converters, such as optical encoders. The print media web speed and the rotational speed of the main cylinder are provided as necessary time pulse inputs to the computer interface 33 so that the computer interface determines the time relationship between the operation of the computer 31 and the inkjet nozzle electronics 35. can be provided with the necessary timing signals to print alphanumeric code characters on a format compatible portion of a moving print media web in a defined correspondence with its form dimensions and position.

Computer interface 33 includes the necessary circuitry to receive transducer signals, form position and print media web speed circuitry 34, control and sequence information data from computer 31, and inkjet nozzle 36.
and inkjet nozzle electronics 35 and associated status signals to control the operation of the entire Computer Lite I system. Computer interface 33 consists essentially of five basic parts, each of which generates the synchronization signals used within the computer interface to control the inkjet nozzle electronics. As will be clear from the following discussion of projecting an ink droplet onto a fixed position on a running print medium, creating an ink droplet and arbitrarily varying the timing of the projection of the ink droplet, There is a need to control the time of ink droplet projection as a function of print media web speed. Computer interface 33 includes a "form head" control circuit that precisely controls the firing of ink droplets as a function of the print media velocity and the "form head" of the primary blank cylinder. This output represents the basic control signal of the computer interface as a modified "head of form" (CTOF) pulse and is used as a reference from which all character starts, stops, and transitions between the computer interfaces are performed. A timing signal is generated to generate subsequent control signals for the inkjet nozzles within the printing unit(s). Once the form size is selected, the CTOF is adjusted accordingly, allowing the inkjet nozzles to print in a staggered or specified manner depending on the form size on the main cylinder.

Computer interface 33 includes a main printhead controller for each printing unit. This main print head controller receives the "head start" information from the computer and is necessary to control the ejection of ink droplets from the first ink jet nozzle for each associated printing unit of the main print head control. generates a timing signal. This timing signal controls the main print head with CTOF pulses generated by counting timing pulses at a rate directly proportional to print media speed. The timing signal consists of a character start pulse (STR1 pulse) that provides a reference frame, and within the reference frame there are 5 stroke pulses (STR2 pulses) spaced apart, in which each STR2 pulse, e.g.
Signal the appropriate time in each column of the x7 matrix and generate the alphanumeric code characters for all computer lights I in this matrix. The main printhead control also separately generates timing signals to control the associated printing units, printheads 2, 3, 4 and 5.
Generates a control effect signal to. The main print head generates a print request signal in the inkjet nozzle electronics prior to the time of actually ejecting the ink droplets, thereby enabling the printing of this printing first unit inkjet nozzle to be driven.

The computer interface 33 also provides the main print head and the print head control 2 for the printing unit.
3, 4, and 5, including a common printhead control circuit that receives device address signals and control function signals to operate printers 3, 4, and 5. This control function signal consists of the DISABLE, ENABLE, STOP PHASING, and START PHASING signals that control the operation of the main printhead control of each printing unit as well as the remaining four printheads of each printing unit. includes a start signal from the computer that synchronizes the operation of the individual printhead controllers.

The computer interface 33 further comprises circuits of the same type for controlling each of the second, third, fourth and fifth print heads of each printing unit and the inkjet nozzles 2, 3, associated with these printing units.
A timing signal is generated to control the flow of ink droplets ejected from each of the ink droplets 4 and 5. These timing signals are also character start pulses (STR1
(STR2 pulses) and character stroke pulses (STR2 pulses), which have the same effect as the similarly named pulses generated by the main printhead controller. However, the character start and stroke pulses from the respective print head controllers 2, 3, 4 and 5 are generated taking into account the displacement of the inkjet nozzles along the line of print media web movement within the printing unit. . This displacement is constant during any given printing operation, but can vary within the limits of mechanical dimensions due to the mechanical structure of the inkjet nozzle itself, and also depending on the formatting to be printed. .
In other words, the spacing between the inkjet nozzles along the line of the movable print media varies as does the spacing between the inkjet nozzles along a line perpendicular to the line of print media web movement. Each print head control 2, 3, 4 and 5 includes appropriate circuitry for timing the occurrence of character start and stroke pulses taking into account the spacing between the inkjet nozzles in the direction of print media web movement. .
Each printhead controller includes circuitry that provides a print request signal to an associated inkjet nozzle to "lead" the associated inkjet nozzle for printing.

The print head control circuit is the same for all printing units and has a computer interface that counts the number of characters printed by each inkjet nozzle and connects the main print head controller and the print head controller 2 of each print unit.
Character start and stroke pulses can be generated or stopped within 3, 4, and 5. It also sends a signal to the computer to indicate that printing of a particular set of variable data has been completed. This circuit also generates register signals for controlling the output of encoded alphanumeric code character data to the inkjet nozzle electronics.

The inkjet nozzles of each printing unit are associated with a set of storage and print buffers that convert character data from the computer data line into 7-bit blocks in response to respective register signals from the common printhead control. Give the ASCII code to the seven output lines. Each inkjet nozzle controller includes a data control circuit that receives and controls addressing, sense lines, and computer information and communicates with each inkjet nozzle to determine its respective state for printing.

The printing format of the example proposed here is
Holds 38 characters. Also, in this example, the length of each 10 characters corresponds to each 1 inch of movement of the print media. The row spacing between the inkjet nozzles of each printing unit and the spacing within each printing unit itself can be varied and controlled by the mechanical structure of the printing press and the mounting of the mechanical structure of the printing unit.

Inkjet nozzle electronics 35 receives the encoded alphanumeric code character data output from computer interface 33 as character STR1 and STR2 pulses to control the printing of alphanumeric code characters for each inkjet nozzle in each printing unit. A matrix generator for each inkjet nozzle generates a series of pulses synchronized with the generation of ink droplets within the inkjet nozzle itself. This pulse train is timed with the character start and stroke pulses from the computer interface, and is timed for each row of the 5x7 matrix to direct the ink droplets onto the moving print media, regardless of the speed of the print media. Line up and project at a designated position.

The pulse train output from each matrix generator is converted by a digital-to-analog conversion circuit and a separate circuit generates a low voltage video signal representing seven different voltages for each matrix column, depending on each matrix generator. This low voltage video signal is amplified and applied as a control voltage for the charge path, thereby
Each successive droplet in the ink droplet stream exiting the inkjet nozzle is provided with the necessary charge to deflect and move it along the perpendicular axis of print media travel. The video amplifier is synchronized with the energization of the piezoelectric oscillator that forms the ink drop at each ink jet nozzle, so that the charging of the ink drop is in phase with the ink drop generation.

The inkjet nozzle electronics 35 also includes a high voltage deflection circuit that applies an electrostatic charge to the electrodes in the deflection path through which each charged ink droplet passes, thereby causing the ink droplet to change its shape depending on the charge carried by each ink droplet. Each ink droplet is deflected while passing through a charge deflection path.
Uncharged ink droplets are not deflected and are intercepted by the ink receiver before being projected onto the print medium and do not contribute to the printing of alphanumeric code characters.

The inkjet nozzle electronics also include well-known phase circuits and sensing circuits for sensing the phase of the ink droplets and correcting the phase if necessary.

Finally, the computer light system includes means for controlling the ink supply and ink flow to each inkjet nozzle, and this means is designated as 37 in FIG.
It is written. Each printing unit has an ink supply manifold that supplies ink in parallel from an ink reservoir to five inkjet nozzles within each printing unit. Uncharged ink droplets are intercepted at each ink reservoir associated with each inkjet nozzle;
Connect a vacuum manifold to each ink receiver and collect the ink. Ink supply 37 also includes appropriate filters and pressure regulators to ensure proper supply of ink to each ink jet nozzle.

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a computer-controlled inkjet printing system, in which alphanumeric characters, symbols, figures, etc. are obtained by inkjet droplets at designated positions on a form for each desired size of the print medium in response to variable movement of the print medium. It is characterized by this.

More specifically, the method according to the present invention uses three printing units each having five inkjet nozzles, and each inkjet nozzle prints several lines of desired message format such as alphanumeric codes. Print. The printing units can be arranged to inkjet print onto defined areas of the print medium and can vary in position relative to each other and in relation to the main printing plate cylinder. The individual inkjet nozzles within each printing unit can also be moved relative to each other. The computer interface also includes circuitry for automatically timing alphanumeric symbols and the like according to the relative positions of the printing unit and the inkjet nozzles. Thus, the printing method according to the present invention has the flexibility to variably print alphanumeric code data at any position throughout the print medium passing through the printing machine. This variable alphanumeric code data can be printed before, after, or at the same time as the fixed data (printed) that is printed in the current general rotary printing system.

Differences between the Present Invention and Prior Art Methods It is well known in the art to print alphanumeric characters by ejecting ink droplets from an inkjet nozzle. In this type of inkjet printing method, when an ink droplet passes through a charging path, an electric charge is applied to the ink droplet, and the deflection of the ink droplet changes depending on the relative size of the electric charge, thereby printing alphanumeric characters. It is something that is drawn on a medium. The magnitude of the charge is changed by rapidly changing the potential of the charge path in accordance with a matrix that forms an alphanumeric code for the magnitude of the charge. Electronic circuits that control the amount of charge and vary the deflection of ink droplets to create individual alphanumeric symbols are also well known. Inkjet printing techniques are used, for example, to print alphanumeric code data on paper held on the movable carriage of a typewriter. Here, the inkjet nozzle moves in response to characters in a conventional format, and the inkjet nozzle and carriage move relative to each other to trace a line of text to be printed. Pressing a specific key on the typewriter activates the inkjet nozzle electronics in response to generate the necessary signals to print the desired character with ink droplets onto the paper medium.

Conventional rotary printing systems use printing plates with alphanumeric characters and graphics depending on the desired text to be printed thereon. This type of method is widely used,
It is widely used for various types of printing, such as newspapers, books, magazines, advertising media, government documents, etc. Such a general rotary printing press can print at high speed. However, changing or modifying the shape of an alphanumeric code graphic to print different text requires a new printing plate, which is expensive. In order to replace this printing plate, it is necessary to stop the operation of the printing machine. Although methods have been proposed to make cheaper printing plates, these improvements still work well with a variety of different text and message formats.
It did not provide the most effective printing method for printing alphanumeric codes matching the . For example, in the conventional method of printing email addresses, it is necessary to write each email address on a master plate. It is necessary to attach this to the original printing plate cylinder or to type the address onto the printing medium using another device.

Computer technology has advanced in various ways, rapidly accepting large amounts of data, processing such data, changing its format, or rearranging input data to create almost any intended input data such as characters, codes, figures, etc. I can give. In this way, computers can calculate salaries, calculate the data needed to launch rockets from the Earth to the moon, control chemical and mechanical processes, and so on.

Traditionally, however, inkjet printing techniques have been used to print on a web (print media) moving at the speed of rotary printing, and (in the early years) to associate this side-by-side with a pre-printed form, with high speed and variable dot printing. There was no way to print letters, kana, kanji, or figures. The present invention combines conventional computer technology, conventional rotary printing technology, and the inkjet technology described above to provide the desired advances and advantages. To the applicant's knowledge, the present invention is the first printing technology that makes it possible to combine inkjet printing with conventional rotary printing.Inkjet printing can accommodate a wide range of printing speeds and is superior to conventional high-speed rotary printing. does not adversely affect the maximum speed of the

The present invention utilizes the speed and effectiveness of modern computer technology to control the charge of ink jet nozzle ink droplets in response to a desired message format containing a variety of alphanumeric code character data. The present invention provides a computer interface that connects the inkjet nozzle electronics to the message data output from the computer. The computer interface generates the necessary timing signals to control the flow of ink droplets through the inkjet nozzle over a wide range of web speed velocity changes and various form size changes. This computer interface also controls and transmits a data code signal corresponding to the changing alphanumeric code graphic data to each inkjet nozzle to print a desired message consisting of alphanumeric code character graphics on the print medium. .

FIG. 4 shows a typical inkjet printing unit 38 of the Computer Lite I system, an example of printing characters, shown in conjunction with a running print media web 39. The five inkjet nozzles 38a, 38b, 38c, 38d, and 38e of the inkjet printing unit 38 are connected to the inkjet nozzles 40a, 40b, 40c, 40d, and 40, respectively.
It is installed so that the line e is printed. As shown in FIG. 4, the print lines 40a-40e are equally spaced from each other. However, this spacing between lines can be varied by suitably adjusting the mounting of the desired inkjet nozzles, or all of them, perpendicular to the direction of travel of the print media web 39. In the computer write method described herein, each inkjet nozzle 38a-38e is spaced a distance D from an adjacent inkjet nozzle within printing unit 38. This distance D is 6.35 cm in the method shown here. However, the attachment relationship between these inkjet nozzles and inkjet printing units is purely for illustration purposes, and the distance D between each inkjet nozzle can be changed as desired by appropriately modifying the circuit of the computer interface. This can be changed arbitrarily, and the relationship and structure/operation will be easily understood from the following explanation.

In the preferred embodiment and in actual use, the inkjet nozzles of the Computer Lite I method are in a horizontal plane relative to the print medium 39, which moves in a vertical plane. However, the position of the inkjet printing unit and the traveling print medium may be interchanged in the vertical and horizontal planes if poor results are found when ejecting inkjet droplets from the inkjet nozzle against gravity. Each of the ink jet nozzles 38a to 38e is located in a plane perpendicular to the plane of the printing medium 39 on which it is running.

Figure 5 shows the inkjet printing units 38, 3.
8' and 38". Each inkjet printing unit 38, 38' and 38" is connected to 38a
38e, 38a' to 38e' and 38a'' to 38e''. The running print media web 39 is driven by drive rollers 41a, 41b shown vertically in FIG. Each inkjet printing unit 38, 38'
and 38″ mounting structure avoids drawing complexity,
Not shown in Figure 3. This inkjet printing unit can be mounted with any suitable mounting structure and at any suitable distance relative to the running print medium 39.

In FIG. 5, there is a main printing plate cylinder (master printing cylinder) 40 and a printing and driving roller 41.
The operation is shown in relation to a. However, this relationship between the original cylinder 40, the printing roller 41a and the inkjet printing units 38, 38', 38'' is for illustration purposes only.
0 can be placed further downstream from the running print medium 39, in addition to the position shown in FIG. It can also be seen that this main printing cylinder 40 can also be placed upstream of the inkjet printing units 38, 38', 38''.
0's "form head" is also shown in FIG. A slit 41 is provided at a distance from the mechanical "form head" and the "form head" is inserted through this slit.
The pulses are generated with suitable optical encoding circuits well known to those skilled in the art. (See Figure 9) Slit 4
2 are placed around the main printing plate cylinder 40 to generate a fixed number of timing pulses for each rotation of the main printing cylinder. In the embodiment shown here, 2500 slots 42 are provided. This electrical "form head" pulse, as well as 2500 pulses for each rotation of print cylinder 40, is applied to the computer interface circuit to provide the necessary timing effects for the operation of this circuit. A transducer is also provided to generate a constant number of pulses per centimeter of print media web movement to generate timing pulses for the computer interface. Although such a converter is not shown in FIG. 5, a speed converter can be used to indicate the speed of a conventional printing press using a conventional drive and gear train mechanism.

The spacing between the inkjet printing units 38, 38' and 38'' can be varied arbitrarily to provide printing of the desired variable data to be printed on the form printed on the main printing blank cylinder. It will be appreciated that the lateral spacing of 38, 38', and 38'' can also be adjusted as desired in the lateral direction of the running print media web 39. This printing can then be done by dividing the main printing plate cylinder 40 in the circumferential direction into a single unit form or into multiple unit forms, in connection with which each of the inkjet printing units can be adjusted as desired. I can do it.

each inkjet printing unit 38, 38';
and 38″ to the main printing plate cylinder 40,
When mounted in a specific fixed relative position, the computer light I method allows the operator to select the "form dimensions" divided into the unit forms described above, so that the computer light interface circuitry can automatically set the start of the character. Inkjet printing can be performed at a fixed position by adjusting the stroke generation and selecting the "form size".

FIG. 6 is an explanatory diagram of the font of the 64 alphanumeric code characters in total. As can be seen in FIG. 6, each alphanumeric code character is made up of a 5.times.7 matrix and will be more fully described in the following specification. Each inkjet nozzle is 64 as shown in Figure 6.
It is possible to generate alphanumeric code characters of characters. The character font shown in FIG. 6 is for illustrative purposes only and other types of fonts may be used in the Computer Lite I method.

Computer Interface “Format Head” Controller The Computer Lite I printing system is capable of matching the printing by the inkjet nozzles to a range of different print media speeds, i.e. from 213 m/min to almost 0 m/min. I can do it. Print media at different printing speeds require different ink droplet ejection times to correspond correctly.

In printing machines using inkjet nozzles, when ink droplets are ejected from the inkjet nozzle,
A certain amount of time is required for the ink droplets to contact the print medium. It is assumed that the gap between the ink jet nozzle and the print medium and the velocity of the ink droplets emitted from the ink jet nozzle are approximately constant. The gap between the inkjet nozzle and the print medium is shown in FIG. The flight time for an ink droplet from an ink jet nozzle to a traveling print medium is short, on the order of a few milliseconds. During high-speed printing, the distance traveled by the print media web during the droplet flight time is considerable, approximately 2.5 cm/
Let's reach seconds. Actual movement can be ignored when printing at low speeds. Therefore, contacting the ink droplets from the inkjet nozzles with precise locations on the emissive print media web is dependent on the emissivity to ensure precise alignment of the inkjet prints at all print media web speeds. It's difficult.

Seventh theory for determining ink droplet emission
Before providing a detailed description of the circuitry for modifying the print media velocity related "format head" pulse as shown in FIGS. 7A and 7B, a brief description will first be provided. First, as is known in the art, the number of pulses per centimeter of travel of the print media web is selected. The example shown here uses 120 pulses per 2.5 cm. A variable timing pulse of this print media web is sent to a first counter. The pulses are then counted continuously at a rate directly proportional to the speed of the print media web. The second counter is driven by a free oscillation oscillator and controls the first counter to define a constant counting period of the first counter. The first counter is restored to 0, and then, after a certain counting period, it starts counting periodically. The number of pulses counted by the first counter thus directly represents the speed of the traveling print media web, and the value is continuously updated with each cycle of the counting operation. This counting period can be short enough so that its value can be known before the running print media web or its speed is significantly changed. A factor to consider in changing the speed of the print media web is the inertia of the printing press, which is fairly large so that the speed of the print media web does not change significantly over short periods of time. Other elements also correct for variations in the speed of the printing mechanism in the circuit described herein with the accuracy of the printing press drive mechanism.

converting the per-count data determined by the first two counters into appropriate line control signals for ejecting ink droplets toward the print media web;
Properly contact the droplet at the desired location on the print media web. This conversion is performed by a third counter, the output of which is applied to digital decoding logic,
Count the number of pulses determined here. For example, the calculated maximum number of cm during the travel of the print medium during the flight of the ink droplet is multiplied by the number of pulses per cm of travel of the print medium counted by the first counter. Such counting yields the maximum number of pulses that occur during flight of the ink droplet.

This circuit can modify the time of ink drop ejection depending on the desired "printing plate size".
The emission of the ink droplets is then adjusted to coincide with the main printing blank cylinder. This “format head”
The circuit will be explained in detail later. However, this "format head" circuit starts counting the third counter,
The print media speed data obtained from the first two counters is used to count pulses up to a predetermined maximum number of counters to set a third counter to a value that should be directly proportional to the print media speed. The third counter then starts the counter with a start pulse, counts the print media velocity from the initial value until it reaches the first maximum count according to the counting pulse, and when the maximum counter is reached, ink droplets are ejected from the inkjet nozzle. It sends a control signal that determines what to radiate.

Assuming that the first counter counts for 12.5 ms, and 120 pulses per 2.54 cm of print media and every minute
Assume a speed of 230m. Then, the first counter counts the number of pulses determined by the following equation during the counting period described above.

213 m/min = 355.5 cm/sec 355.5 cm/sec x 120 pulses/2.5 cm x 12.5 ms x 1 sec/1000 ms = 2100 pulses By knowing the ink droplet velocity and the distance between the ink nozzle and the print medium, the maximum of the print medium can be determined. It has been found that at a speed of, for example, 213 m/min, an ink droplet needs to be ejected 1.48 cm in advance to actually align the inkjet nozzle with the desired print spot on the print media. This calculation was confirmed experimentally by actually measuring the displacement of the ink droplet at a print media speed of 213 m/min under the fixed coefficients assumed above. Therefore, the following conclusion can be drawn from the above explanation. i.e. 120 for every 2.54 cm of print media movement
213m/min from pulse and 1.48cm displacement of ink droplet
The number of pulses required to be counted by the third counter described above to eject an ink droplet at the appropriate time with a print media speed of . This calculation is performed as follows.

Number of pulses = 1.48 cm x 120 pulses / 2.54 cm = 70 pulses In the embodiment of the system shown here, the optical encoder is mounted in relation to the master cylinder and its position is 1.48 cm from the actual mechanical "format head" position. Generate a head-forming pulse before cm. This is illustrated in Figures 5 and 9. Furthermore, when the print media is traveling at 213 m/min, the ink droplet from the inkjet nozzle actually matches the desired point on the print media with the position of the inkjet nozzle.
I found out that I had to radiate 1.48cm in advance. Thus, for the maximum print media speed, the third counter first presets the pulse coefficient and makes this value correspond to the maximum print media speed (i.e. 70 pulses in the above example), thereby causing the ink droplets to Radiate without delay. From the above description, it has been found that by appropriately presetting the third counter, the time of droplet ejection can be determined for any print media speed. Referring to Figure 9, print media speed is
The distance Y from the encoding format head when the speed is slower than 213 m/min is determined as follows.

Y distance = 1.48 cm x printing medium speed m/min/213 m/min Further, based on the above discussion, the number of Y pulses to be preset in the third counter is determined as follows.

Y pulse = 70 pulses x print media speed m/min/213m
No. 332,534, filed on January 10, 1973, of the present inventor, which shows the above-described counter circuit for generating correction pulses in response to different print media web travel speeds, such speed correction is possible. It is quoted here for the purpose of explaining the operation of the circuit.

The Computer Lite I system can also match inkjet printing to "printing plate size." The main printing plate cylinder is shown in FIGS. 5 and 9. The master cylinder can have different dimensions and different circumferences. For purposes of this specification, the circumference of the master cylinder is assumed to be 43.2 cm. Typical dimensions are, for example, a 43.2 cm format (full expansion), which is the "printing plate size" of 1.
The "printing plate size" in 2 refers to a 21.6 cm format placed in half of the master cylinder, and two sheets of the format are printed for each rotation of the master cylinder. 3. “Printing plate height” corresponds to dividing the original plate cylinder into 33 parts. 4 "Printing plate size" means dividing the master cylinder into four parts, etc. "Printing plate size" varies depending on the "format head" controller as described above with reference to FIG. 9. Since it gives a pulse to start the counting of the third counter mentioned above, taking into account the size of the printing plate,
This inkjet printing can be matched to formats of different sizes.

The "format head" controller requires timing data to perform the functions previously described. Referring to Figures 5 and 9, the electrical "format section"
The (ETOF) pulses are disengaged with a mechanical "format head" on the master cylinder 40, which for each revolution of the master cylinder is passed through a suitable transducer, e.g. a slit 41 forming part of an optical encoder. It can be given by Further, additional timing pulses are passed through the slit 42 forming part of another optical encoder.
It is given by a converter like . For the embodiment described here, the blank cylinder 40 includes 2500 uniformly spaced slits 42 around the circumference of the blank cylinder 40, with each revolution of the blank cylinder
Generates 2500 pulses. Finally, a timing pulse is generated depending on the speed of the print medium. For the following explanation, the speed of the print medium relative to the time measurement rate is set to 120 pulses per 2.54 cm movement. Such pulses can be generated in many ways to those skilled in the art. For example, the print media web velocity can be taken directly from the print drive mechanism by a gear and converted into pulses by a suitable electrical transducer. The above-mentioned electric "format head" structure that generates pulses produces 2500 pulses per rotation of the original cylinder, and the same 2.54 cm of print media.
Since there are 120 pulses per movement, this will be well understood by those skilled in the art and we do not believe it is necessary for the purposes of the present invention to explain further details of each mechanism.

Detailed Description of the "Format Head" Controller The following is shown in Figures 7A and 7B. Description of the "format head" controller. ETOF pulses from an optical encoder associated with master cylinder 40 appear at terminal 60. This ETF pulse is used to generate the pulse for the speed correction counter and is also used as the erase pulse for the "plate size" counter. This is OR gate 62 (4 common input AND gate) OR gate 64
(2 common input NAND), an inverter 66, and an inverter 68 that serves as a Schmitt trigger. The drive pulses generated by the circuit described later activate the operation of the "format head" controller, which is activated by the computer instruction SYRT and the NOR gate 70.
Occurs in The ETOF pulse at terminal 60 is coupled to the "format head" shown at the bottom of Figure 7A along with selected outputs of the numerical decoding circuit (described later).
(TOF) switches 1, 2, 3, and 4. This can be selected by the operator. This ETOF passes through NAND gate 72
Enter the TOF switch I contact point. TOF switch 2
Inverter 74, NOR gate 76 and
Through the NAND gate 78, the TOF switch 3 has an inverter 74, a 4-input NOR gate 80,
Through the NAND gate 82, finally the TOF switch 4 has an inverter 74, and a 4-input NOR gate 8.
4 and NAND gate 86.

The rotation (PCR) pulse of the printing plate cylinder is passed through the terminal 88, and further the OR gate 90 (4 common input NAND), the NOR forming the Schmitt trigger.
Timing pulses are counted through the gate 92 (2 common input NAND) and inverters 94 and 96,
Binary counters connected in series 98,10
Give clock pulse input to 0,102. The outputs of the counters 98, 100, and 102 are decoded by a numerical decoding circuit, which consists of the following components and operates in the following manner.

The selected outputs from the binary counters 98, 100, 102 are inverted by an inverter 104, and the outputs are transferred to the binary counters 98, 10.
Numerical decoding circuits 106, 108, 110, 112 and 114 along with other selected outputs from 0, 102
Add to the input. The numerical decoding circuit 106 has a numerical value of 1250.
decrypt. Numeric decoding circuit 108 has its input selected to decode the numeric value 833. The inputs to numerical decoding circuits 110, 112 and 114 are also suitably selected to decode the numerical values 1666, 625 and 1875, respectively. Since the printing plate cylinder is divided into 2500 pulses, the values of decoders 106 to 114 are 1/2, 1/3, 2/3, and 2/3 of the circumference of the plate cylinder, respectively.
It is easy to see that the pulses representing 1/4 and 3/4 are decoded. Numerical decoders 106, 108, 110,
The outputs of 112 and 114 are NOR gate 11
Enter inputs 5, 116, 117, 118 and 119. The output of NOR gate 115 (representing 1250 pulses) is the input to NOR gates 76 and 84. The output of NOR gate 116 (representing 833 count pulses) becomes the input of NOR gate 80. NOR gate 117 (represents 1666 counts)
The output of is the input of NOR gate 80. The output of NOR gate 118 (representing counting pulse 625) is
This is the input of NOR gate 84. Finally, the output of NOR gate 119 (representing counting pulses 1875) is
It becomes an input to the NOR gate 84.

From the above explanation, NOR gates 72, 78, 82
It is readily seen that the outputs of and 86 represent pulse trains representing "printing plate sizes" of 1, 2, 3, and 4, respectively. The pulse train outputs from TOF switches 1, 2, 3, and 4 are inverted by an inverter 116 and used for control operations that will be explained in detail later.

Inverter 104 and two counters 98, 100 and 102 performing the necessary numerical decoding
The circuitry constituting the numerical decoding circuitry described above, including the connections for the input outputs, is extremely well known to those skilled in the art, and detailed circuitry is not believed to be necessary for the purposes of the present invention. Those skilled in the art can readily implement the known decoding operations specifically mentioned above to provide a decoding circuit.

When this "printing plate size" is selected, the NOR gate 7 must be properly set to select the correct phase.
It is necessary to apply the computer SYRT pulse from 0 to the phase control flip-flop 118. This makes it possible to eliminate the possibility of starting printing on the second half of the master cylinder. SYRT command pulse clears flip-flop 118 and ETOF
When the pulse switches flip-flop 118
Counter 98, 10 at the output of AND gate 120
Pay 0,102. The inputs to AND gate 120 are either SYRT pulses or ETOF pulses, which are NOR'ed through inverters 122 and 74, respectively.
It becomes an input to gate 124.

The SYRT computer command, like other data and control signals, is an input from the computer to the startup circuit 130 as follows. “Format head” control circuit
Addressing is performed by the computer using the IUAX control signal and the first 6 bits of the computer E line, that is, signals from the EO bit to E5. The above address bits are applied to NOR gates 132 and 134, respectively, and their respective outputs are applied to a three-input NAND gate 136 along with a control signal IUAX. The output of the NAND gate 136 is inverted by an inverter 138 and added as one input to a 4-input NAND gate 140. NAND gate 14
The other three inputs of 0 are from the computer (external control commands)
(EXC) outputs as EB6, EB7 and EB8 bits on the computer data line. NAND gate 140
The output is the control signal from the EB11 bit computer.
Enters the input of NOR gate 142 along with FRYX,
Its output goes into the input of the NOR gate 70, along with the computer control signal SYRT, which drives the "printing plate size" circuit and generates the ETOF pulse ("printing plate size"), as will be explained later. (corrected by the circuit).

Computer interface timing pulse CP is generated by timing oscillator 150. 120 pulses/2.54cm
The converter input of is applied to terminal 152 and goes to an OR gate 154 (4 common connected input AND), a NAND gate 156 consisting of a Schmitt trigger, and inverters 158 and 160. In order to avoid complicating the drawings representing the logic circuit of the computer interface, the clock pulse was named CP and used for the entire interface circuit.

The following is a description of the aforementioned counter circuit for generating the modified "head of format" (CTOF) pulse obtained in connection with FIGS. 7A and 7B.
The clock pulse inputs of flip-flops 162, 164, and 166 in circuit 160 divide the CP pulse by five. The outputs of flip-flops 162 and 164 are applied to the respective inputs of OR gates 166' and 168, respectively, and the outputs of these gates are applied through NOR gate 170 to the J input of flip-flop 166. The Q output of flip-flop 162 controls flip-flop 164. The output of flip-flop 166 is transferred to flip-flop 162.
The Q output of flip-flop 166, connected to the J input of circuit 160, represents 1/3 of the CP input of divide-by-5 circuit 160.
Flip-flops 162, 164 and 168 are
It is reset by the SYRT instruction.

The output of flip-flop 166 is the CP input of binary counter 168', which is part of the first counter 169 previously described and shown in FIG. 5B. The second counter 171 shown above consists of a binary counter 170', 172 which periodically counts the pulses from a 10 KHz oscillator 174. This gates the split pulse from flip-flop 166 for a period of 12.5 ms into first counter 169 in the following manner. Binary counter 170', 17 for each 12.5ms
2. Inverter 176, NAND gate 178,
Inverter 180, NAND gate 182, and inverter 184 provide outputs to gate 182. NAND gate 182 is also “printing plate size”
It is controlled by receiving a modified ETOF pulse from the TOF switch mentioned earlier. The first counter 169 is
It is reset by the pulse output generated by NAND gate 186 and NAND gate 188. The other input to NAND gate 188 is the SYRT instruction. NAND
Input to gates 178 and 186 is inverter 1
76 and the binary outputs of binary counters 170' and 172 are selected as drops, and the NAND gate 178
and 186 provide output pulses of 12.5 ms and 12.7 ms, respectively. As mentioned earlier, such numerical decoding circuits are known to those skilled in the art. 12.7ms is binary counter 170' and 172
This is convenient because it can count 128 and then repeat the cycle. This allows the time delay necessary to reset first counter 169 and second counter 171.

The final counting stage of counter 168' is coupled to the CP input of counter 188. 22-decimal counters 168' and 188 of the first counter 169
The binary counter counts accumulated in the inverter 184 are set in four latches 190 and 192 every 12.5 ms by the pulse output of the inverter 184. 4 latches 19
The speed information of the print media accumulated in 0,192 is the same.
3rd counter 19 by pulse every 12.5ms
7 into the binary counters 194 and 196. In this way, the binary counters 194, 196 each
Preset print media speed data every 12.5ms.

As mentioned before in this flip-flop 200
The TOF switch provides a "plate size" correction ETOF pulse through line 201, and the output of flip-flop 200 controls gate 198, so that the print media velocity CP pulse is incremented through NAND gate 198 (FIG. 5). Enter binary counters 194 and 196. binary counter 19
When 4,196 reaches the maximum predetermined count value, a pulse is generated from NAND gate 202. This maximum preset value is the number of pulses that will eject a proper ink drop at the maximum print media speed. In the previously described embodiment, this number of pulses is 70 pulses. The maximum preliminary setting count is determined by a numerical decoding circuit consisting of an inverter 204 and a gate 202, and this inverter 204 is a binary counter 1.
After receiving selection input from 94 and 196, gate 202
is an inverter 204 and a binary counter 194,
Receives necessary input from 196. NAND gate 2
The pulse output from 02 is a velocity modified "head of format" pulse (CTOF) which is used as the basic timing circuit for the computer interface and as the character print control signal for STR ₁ and STR ₂ . A binary output 64 from counter 196 is used to switch flip-flop 200 (FIG. 7A) to stop the CP input to third counter 197.

Main Printhead Controller In computer-light systems, drive/inhibit external computer commands can be used even while printing is in progress, for example, when the print operator does not wish to print while it is "preparing" or performing other operations. It can be used to drive or inhibit a computer interface. In such cases, the computer can inhibit the printhead controller. The last thing the computer does before starting printing is to activate all print head controllers. The computer interface includes a main printhead controller, which controls one inkjet nozzle head in the printing unit, one such controller being shown in FIG. 8 for purposes of this specification. . The main printhead controllers for printing units 2 and 3 are also similar to that shown in FIG.

Device address (D/A) to inverter 234
(Figure 6) and inverts the 4-input NAND gate 260.
It is used as one input. Computer is NAND gate 26
0 is set on control signal FRYX and data line _EB14 . A flip-flop 262 is set by the output from the NAND gate 260, and this flip-flop is switched by the computer signal DRYX.
2 is operated by the output of the flip-flop 262 and the computer signal DRYX to output the signal from the NAND gate 272.
24 bit counter 26 through LOAD pulse
4, (4 bit counters 266, 268 and 2
70 connected in series). This allows the head start count from the computer to be calculated from EB ₀ to
Set to counter 264 through EB ₁₁ 's computer data line. The previously mentioned CTOF pulse
Gate with AND gate 274 (other inputs are set appropriately with the output of 0 decoder 306 shown later)
Toggle flip flop 278 heinverter 2
You can put it through 76. The Q output of flip-flop 278 is applied to the input of NAND gate 280 along with the control medium movement pulse CP, and counter 270 begins subtracting from the "head start" count accumulated by the computer.

It is necessary to provide the inkjet nozzle electronics with a print request signal that causes the ink droplets to be charged, for example at high voltage, before actually starting printing. (See Figure 10). This print request applies 240 pulses to the inkjet nozzle electronics, or at least 5 cm before the inkjet nozzle reaches the desired print point on the print medium. The decoder 282 outputs the octal number 360, which is equivalent to 240 in decimal.
Decoding is performed by an octal-+-adic decoding logic circuit consisting of NOR gates 284, 286, and 288. The input to NOR gate 284 is taken from counter 266 as shown in FIG. NOR gates 286 and 28
The input to counter 2 is as shown in Figure 8.
It is taken from the output of 68. Inverter 290, 29
2, 294 and 296 appropriately invert the signal,
NOR gates 286 and 288 as shown in FIG.
Add to the input. The output of NOR gate 284 is
The outputs of NOR gates 286 and 288 together serve as inputs to decoder 282. The output of the decoder 282 becomes the input of the AND gate 298 together with the computer command STOP.PHASING. The generation of the "end of message" signal (EOMS) will be explained later, but this signal and the computer command START.PHASING are input to the AND gate 300, and its output is the drive pulse.
Together with E ₁ , it becomes an input to AND gate 302 . AND
The output of gate 302 is connected to flip-flop 304.
, and the output of AND gate 298 switches flip-flop 304 to cause the inkjet nozzle electronics to output the first inkjet nozzle from the first inkjet nozzle before reaching the desired print media print point.
Sends a print request signal of cm or 240 pulses. This print request signal to the inkjet nozzle electronics is a command to request preparation for printing, which stops the phase mode and enters the print mode. This 5 cm was chosen to achieve a high pressure level for the inkjet nozzle electronics and to provide the necessary time to interrupt the phase taking into account the maximum print media speed of 213 m/min.

At the same time, counter 2 is
64 continues to count down with the print media velocity pulse CP provided by NAND gate 280. Zero decoder 306 includes counters 266, 268 and 2 as shown in FIG.
NOR gate 30 connected to each output of 70
8, 310 and 312 to determine the zero count in counter 264.
The output from zero decoder 306 represents an apparent start pulse (ASTR1) which drives printhead controllers 2, 3, 4 and 5 associated with the printing unit's main printhead controller. ASTR ₁ is also an input to divide-by-12 circuit 318 through flip-flop 316 and inverter 320. Flip-flop 316 is set by AND gate 444 (described later) and toggled by ASTR ₁ . This Q output goes into an AND gate 322 along with the print media velocity CP pulse, where the CP pulse can go into a divide-by-12 counter 318. counter 3
18 outputs to NAND gates 324, 326 and 3
28 to decrypt it. Each line of print contains 10 characters per 2.54 cm, and there are 120 timing pulses for every 2.54 cm of print media movement, resulting in 12 pulses per character. 1st
Referring to Figure 0, the relationship between the character start 1 (STR1) pulse and the stroke 2 (STR2) pulse is shown. There are 5 stroke 2 pulses for each start 1 pulse. Therefore, in total there is one start pulse and five stroke pulses for each character. The output of the NAND gate 328 is transferred to the inverter 33
It is inverted at 0 and is input to NAND gate 332 along with signal Δ (the generation of which will be explained more fully below). The output of NAND gate 332
When applied to the NAND gate 314 along with ASTR ₁ , the required output STR ₁ is obtained and the inkjet nozzle 1 is controlled by the main print head controller in the printing unit.
Generate each character from . The STR ₂ pulse is generated at the output of the NAND gate 326 and is used to select the X1,
Five pulses are constructed corresponding to controlling the determination of X2, X3, X4 and X5, respectively.

The main printhead controller described above operates periodically in the manner described above for each printing unit. Since there will always be a change in information when a type of different location on print cylinder 40 needs to be printed, the computer provides the necessary "head triggers" to counter 264.

Inkjet Nozzle Electronic Circuit FIG. 11 shows the main parts of the inkjet nozzle electronic circuit, the signals generated in the inkjet nozzle electronic circuit, and their uses for each element of the inkjet nozzle at the bottom of FIG. Matrix generator 550 receives a set of encoded (ASCII) characters on data lines L1-L7 from the computer interface previously described. Matrix generator 550 also receives character generation timing pulses STR ₁ and STR ₂ from each of the computer interface's main printhead controller and printhead controllers 2, 3, 4 and 5 circuits. The computer write system requires 15 inkjet nozzles, each of which prints a separate alphanumeric code character, and 15 matrix generators 550, each with a separate data line L1-L7.
Receives character signal timing data STR ₁ and STR ₂ from the printhead controller in relation to the individual character data above and the particular inkjet nozzle.

Each matrix generator 550 generates a digital pulse train in which each pulse generates one ink droplet.
represents an individual. The matrix generator also generates timing pulses, and the digital pulse train and timing pulses described above are received by a D/A conversion circuit 552 (video generator), where the timing pulses are used to convert the digital pulse train into an analog video signal. The output of this video generator 552 represents the low level video of each character received by matrix generator 550. Low level video character data from video generator 552 is applied as an input to final amplifier circuit 554. This circuit basically consists of the following elements. That is, it consists of an inkjet nozzle drive circuit, a video amplifier circuit, and a high voltage video deflection circuit. Inkjet nozzle drive circuit
Generates a 66KHz sine wave and inkjet nozzle 5
The piezoelectric crystal in 56 is excited. This purpose will be explained in detail later. The 66KHz sine wave periodic signal is sent from the video generator 552 to the final amplifier circuit 55.
4, the inkjet nozzle drive circuit is entered.
Video generator 552 transmits the PRT-RDY signal previously discussed and receives the PRT-REQ signal discussed in connection with the computer interface.

The video amplification portion of the final amplifier circuit 554 amplifies the low voltage video character data from the video generator 552 and applies its output to a charging path 558 to input the low voltage video character information generated by the video generator 552 from the matrix generator 550. Associated one of seven electrical potential charges (young or uncharged) is applied to the selected ink droplet. The charging of the droplets that generates the alphanumeric code characters is described in further detail in connection with FIG.

The ink jet nozzle 556 is excited at 66KHz, and at the same time the ink jet nozzle 557 (details will be explained later) is excited.
When pressure is applied to the inkjet nozzle through the opening, the ink separates into droplets that are divided into 66,000 droplets per second.

The high voltage deflection circuit of the final amplifier circuit 554 is connected to a deflection path 560 (which is rotated 90 degrees relative to the actual ink droplet position in FIG. 11), where the droplet passes through a charging path 558. It is bent by a distance proportional to the amount of charge it receives. In actual inkjet nozzle embodiments, the ink droplet is
It is deflected away from the plane of FIG. 1 and strikes the top of the running print medium 562. Those ink droplets that do not receive a charge as they pass through the charging path are undeflected in the deflection path 560 and enter the ink receiver 564, from where they return to the ink supply reservoir through the vacuum return tube 566.

A sensing portion 568 is mounted within the ink receiver 564 to detect ink droplets during the phase mode of the ink jet nozzle. Simply stated, it detects whether ink droplets are produced in the correct phase and assumes proper charge. If the ink droplet is not properly charged, adjust the phase of the 66KHz excitation signal applied to the inkjet nozzle to bring the ink droplet into the correct phase. This phase of the ink droplets and the circuitry and sensing operations that provide this phase are described in, for example, US Pat.
(both announced on September 2, 1969) and JJStone, etc.
No. 3,562,761, published February 9, 1971. The ink drop phasing techniques and apparatus shown in the above-mentioned US patents are described herein only for the purpose of understanding the operation and manipulation of ink drop phasing for use in computer light systems. However, it should be understood that the circuitry for ink drop detection and phasing is not itself or a part of the present invention. Phase and droplet detection 57 in Figure 15
0 detects the droplet and adjusts the phase, and sends a phase signal to the video generator 552, where the PRT
Generate RDY signal.

The hole diameter of the inkjet nozzle is 0.00508cm in diameter.
The distance between the running print medium and the computer light system shown here is approximately 1.72 cm.

Embodiments of the Invention The main printing plate cylinder includes a mechanical format head, and the signal means generates a format head pulse for each rotation of the main printing plate cylinder, and the signal means generates a format head pulse for each revolution of the main printing plate cylinder. The computer interface further includes a first pulse generating means for generating a first pulse having a pulse rate corresponding to the rotary printing speed; counting means for counting the first pulses at regular intervals in order to determine the first pulse.
The above printing method is characterized in that it includes timing signal adjusting means for correcting the formal head pulse in accordance with the rotary printing speed determined by the pulse.

The counting means includes a first counter for counting the first pulse, and includes a counter control means for controlling the first counter to count for a certain period of time; the counting means for correcting the format head. The timing signal adjustment means further includes a second counter for accumulating counts in the first counter and for generating a signal indicative of the modified format head.

A second pulse generating means for generating a second pulse having a fixed number of pulses for each rotation of the printing plate cylinder, and the timing signal adjusting means further includes a third counter for counting the second pulse. , numerical decoding means for determining a number of pulses corresponding to the size of each printing plate in said printing master cylinder, and for gating the number of decoded pulses into said counting means corresponding to said format head pulse. gate means.

the inkjet nozzles are mounted in separate printing units; the inkjet nozzles within the printing unit are mounted offset along an axis parallel to the direction of movement of the printing medium; each inkjet nozzle independently controls the flow of ink droplets; said timing signal adjusting means further comprising a master controller and several slave controllers for controlling each of the separate printing units, said master controller controlling said running The slave controller controls each specific nozzle of the remaining inkjet nozzles in a specific unit of the separate printing units. In particular, each said master controller generates signals that control the ejection of ink droplets from an associated ink jet nozzle, and each said master controller generates signals that control the ejection of ink droplets from an associated ink jet nozzle, and each said master controller generates signals that control the ejection of ink droplets from an associated ink jet nozzle. generating a second timing signal for driving a slave controller in the printing unit and generating a third timing signal for controlling ejection of ink droplets from an associated inkjet nozzle; corresponding to said modified format head for controlling a slave controller in each printing unit associated with an inkjet nozzle, said slave controller controlling the ejection of ink droplets from the associated inkjet nozzle; generating additional timing signals for controlling the slave controllers in connection with each gradual shift of the inkjet nozzles in each printing unit.

a first pulse comprising a pulse rate determined at least in part by the speed of the traveling print medium, a second pulse intervening between the first pulses, the first pulse defining an interval for printing successive alphanumeric code characters, and the time period. said master and slave for controlling the ejection of ink droplets, each comprising said second pulse for controlling inkjet droplet flow from an associated inkjet nozzle for printing said alphanumeric code characters within an interval; It has a signal from the controller.

The computer interface further includes a print buffer memory for controlling the transmission of the character signal to the inkjet nozzle electronics, and transfers pulses from the modified format head pulse to the first and second pulses to the buffer. Shifting means for shifting data from a buffer register to said print register; storing character signals in said buffer register one after another; and transmitting said character signals to said inkjet nozzle electronics. .

Advantages of the Invention The printing system of the invention is capable of printing variable alphanumeric codes by ejecting ink droplets from multiple inkjet nozzles over a wide range of common printing speeds. Furthermore, this variable alphanumeric code data can be correlated and matched with fixed data printed on a print medium using general printing technology. This variable alphanumeric code data, such as a list of customer addresses, can be incorporated into any multiline message format by a computer stored on paper tape, magnetic tape, punch cards, etc. The computer interface according to the invention is capable of responding to commands from the computer to data signals, signals representative of the general printing speed, and the desired "plate size" on the main plate cylinder of a conventional printing system. It can generate alphanumeric codes, timing signals, transmit encoded character data from a computer, and drive inkjet nozzle electronics that control the charge of the ink droplets ejected by the inkjet nozzle.

The computer interface automatically adjusts the delay or acceleration of alphanumeric code transmission depending on the prevailing print speed, since changes in the prevailing print speed cause misalignment of charged ink droplets on the print media. The operator can arbitrarily select the number of "printing plate sizes". Since each “printing plate size” is associated with a different area on the surface of the main printing plate cylinder,
Selected. Automatically match variable alphanumeric code data with fixed format according to "printing plate size". The alphanumeric timing signals are adjusted according to the size of the printing plate in order to keep the alphanumeric code data properly aligned on the print media.

This printing method uses three printing units. Each consists of five independent inkjet nozzles in which each inkjet nozzle prints one line in the desired alphanumeric message format. Each printing unit is individually mounted to perform inkjet printing on a respective defined area of the print medium. Their relative position to each other and to the main printing blank cylinder can therefore also be varied. The individual inkjet nozzles within the printing unit can also be moved relative to each other. The computer interface can automatically adjust the alphanumeric code timing signals associated with the printing unit position and inkjet unit nozzles. The present printing system thus facilitates the flexible printing of variable alphanumeric code data at any location across or along the print medium as it moves through the printing system. This variable alphanumeric code data can be printed virtually simultaneously before or after a fixed format printed using common rotary printing techniques.

The present invention also utilizes the fast and efficient characteristics of computer technology to relate the timing of charge formation on ink droplets produced within an inkjet nozzle in a desired message format containing variable alphanumeric code character data. It can be controlled by The printing method proposed here consists of an office document printing device, a computer control device for printing formats (ordinarily direct mail advertising documents) using ordinary impact printing technology, and variable printing using non-impact inkjet printing technology. This shows a combination of data input and printing. This variable data may be the addressee or information that changes in relation to the print format.

The non-impact inkjet printing system proposed here can be installed in conventional general printing machines with almost no reduction in speed or efficiency.
This non-impact inkjet printing method is
Since it is a modular system, it is notable for its portability. It is also characterized by its adaptability, allowing a wide range of changes to be made to the printed material. With the printing system of the present invention, procedures can be consolidated while other tasks are performed on the printing machine, and failure and replacement times for this printing system are short.

The press interface includes the circuitry necessary to receive conversion signals representing print media speed data control, information from the computer, and status signals from the inkjet nozzle electronics to synchronize the inkjet nozzles and operate the entire printing system. control. The computer interface consists essentially of five basic components, each of which is used for synchronization between itself and to generate various control and synchronization signals for the proper operation of the inkjet nozzle electronics. . A "format head" control circuit within the computer interface precisely controls the ink droplet ejection from the inkjet nozzle as the velocity of the print media is a function of the format head of the main printing plate cylinder. Control of the printing units, including the inkjet nozzles, is facilitated by the use of a main printhead controller for each printing unit, which first contacts and corrects the area on the print media where variable alphanumeric code characters are to be printed. The "format head" generates the timing signals necessary to control the ejection of ink droplets from the inkjet nozzles in each printing unit. The remaining inkjet nozzles in each printing unit are controlled by head control circuits, which are identical, thus significantly simplifying the complex computer interface. A timing signal is generated by the main print head controller, the head control circuit sets a standard frame for each character, and within this standard frame, five spaced character stroke pulses are generated, forming a matrix of five columns and seven rows. All alphanumeric code characters can be printed by ejecting ink droplets at the correct times in relation to each column of .

The modular nature of the computer interface is such that a common printhead control circuit operates the print unit's main printhead controller and printhead controllers 2, 3, 4, and 5, so that machine address signals from the computer and inkjet nozzle circuits are used. and control functions. The common printhead control circuit counts the number of characters printed by each inkjet nozzle, maintains control of character transmission between the counter and the inkjet nozzles, and issues an end-of-message signal to control the number of characters printed from each inkjet nozzle. Stop characters from occurring.

[Brief explanation of the drawing]

Fig. 1 is a principle diagram showing the relationship between impact printing and inkjet printing according to the present invention, Fig. 2 is a principle diagram showing the temporal correlation when printing in Fig. 1, and Fig. 3 is a principle diagram showing the relationship between impact printing and inkjet printing according to the present invention. Figure 4 is a principle diagram showing the components of the computer light system in the form of a block diagram. A layout diagram showing the relationship between the lines and the print output, FIG. An example will be shown, and the principle of the relationship between the main printing plate cylinder and the printing unit for printing a format will be shown, and variable data will be printed in this format at a fixed position in relation to the main printing plate cylinder. Figure 6 is a character diagram showing the fonts (character shapes) constituting the 64 alphanumeric code characters made up of a 5x7 matrix, and Figures 7A and B are the "format head" diagrams. Figure 8 is a circuit diagram of the main print head control interface, Figure 8 is a circuit diagram of the computer print head control interface.
3, 4, and 5 interface circuit diagrams, No. 9
Figure 10 shows a side view of the main printing plate cylinder showing the coding slits used for printing plate size and inkjet nozzle timing; Figure 10 shows the relationship of the various control signals of the computer interface as a function of a given printing speed; Time chart shown, 1st
Figure 1 is a combination block diagram showing the functions and relationships between the inkjet nozzle electronic circuit and the inkjet, and shows the correlation between the electrical signals for operating the inkjet nozzle and the elements of the print medium running through the inkjet nozzle. FIG. 3 is a block diagram showing the relationship between ink droplet flows.

Claims (1)

Claims: 1. Printing a fixed form at rotary printing speed on a web print medium 39 of printing paper being run by a master printing cylinder 40, and printing variable alphanumeric characters to match the dimensions and position of the form. data 40a
-d, the variable character data 40a to 40d to be printed in accordance with several lines selected on the form are encoded, and a computer is used to process the encoded signals to print the characters on the form. Means for providing character timing signals (STR- ₁ , STR- ₂ ) for specifying the sequential position of the several lines of character data to be printed on the machine; means for generating a form head pulse before passing; means for generating N pulses (N = integer) for each rotation of the master cylinder; and means for counting the pulses so that the count value is N×m/n. a plurality of counter means, each of which generates an output when the number of counter means (n, m = integer) is reached, and among the plurality of counter means, one of the counter means corresponding to the form dimension set on the master cylinder; A selection switch means for selectively outputting only the output, and a means for generating pulses having a pulse rate corresponding to the web speed are provided, and the counter output selected corresponding to the form dimensions and the pulse rate according to the web speed are provided. The timing of the form head pulse is modified to adapt to the form dimensions and web speed using the modified pulse, and the timing of the character timing signals (STR- ₁ , STR- ₂ ) is automatically adjusted according to the modified form head pulse. and separate ink droplets 559 on the running web 39 in response to the character timing signal.
A computer-controlled inkjet printing method characterized in that the variable character data is printed by injecting the variable character data.