JPH0930006A - Inkjet print recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with a sensor for detecting the residual amt. of ink by calculating the residual amt. of ink by using a count means counting the number of jet commands of ink. SOLUTION: A second control circuit 34 converts the jet data based on the dot data received from a first control circuit 33 to serial data by a parallel/ serial converter 38 and the serial data and a printing timing signal are outputted to a drive circuit 40. The drive circuit 40 converts the serial data to parallel data by a serial/parallel converter 42 and drives a printing head 10 through a driver 43 to inject ink to perform printing. A dot counter 39 counts the number of jet commands in parallel to printing operation to count the consumption amt. of ink. Since the dot counter 39 outputs the data corresponding to the number of jet dots, a CPU 36 can calculate the residual amt. of ink on the basis of this output and the number of injectable dots determined from the preliminarily cleared total amt. of ink of a new cartridge.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet print recording apparatus for printing by ejecting ink from a print head onto a printing medium.

[0002]

2. Description of the Related Art Conventionally, in an ink jet type print recording apparatus, when the amount of ink remaining in an ink cartridge for supplying ink to a print head becomes low, a warning is given to the user to prompt a replacement of the ink cartridge. Is going. In order to perform this process, it is known that the remaining ink amount is detected by directly detecting the remaining ink amount using a sensor or by calculating the ink ejection amount from the print data by a control circuit such as the CPU of the apparatus. Has been.

[0003]

However, in the conventional ink remaining amount detecting method as described above, the former requires a sensor and becomes expensive, and the latter requires the number of character codes to be printed in the CPU of the control circuit or the like. Alternatively, since the number of dots, that is, the ink ejection amount is calculated from the image data, the calculation load on the CPU or the like increases, which adversely affects the processing speed of other functions.

The present invention has been made to solve the above-mentioned problems, and by using the counting means for counting the number of ink ejection commands, a sensor is not required for detecting the remaining ink amount. It is an object of the present invention to provide an ink jet type printing recording apparatus which is inexpensive and does not adversely affect the processing speed and the like because the detection of the remaining ink amount does not impose a load on the CPU of the control circuit.

[0005]

In order to achieve the above object, an ink jet type printing recording apparatus according to the invention of claim 1 is
A print head that ejects ink onto a printing medium, an ink cartridge that supplies ink to the print head, control means that outputs an ink ejection command based on dot data to be printed, and based on the ink ejection command In an ink jet type printing recording apparatus having a driving unit for driving a print head, a counting unit for counting the number of ink ejection commands output from the control unit is provided, and the count value by the counting unit and the total ink amount of the ink cartridge It is possible to output an ink remaining amount signal from. In the above configuration, the ink consumption amount can be known only by counting the ink ejection command number, that is, the number of dots, from the control unit that outputs the ink ejection command, while the printing can be performed by the total ink amount of the ink cartridge. Since the number of different dots is known in advance, the ink remaining amount can be immediately obtained from these.

According to a second aspect of the present invention, there is provided an ink jet print recording apparatus, wherein:
In addition to the ink ejection command number, the counting unit is configured to add the ink amount consumed during maintenance of the print head. In the above configuration, the amount of ink consumed during maintenance of the print head is added to the number of ink ejection commands to count, so that a more accurate amount of ink consumption can be known.

Further, in the ink jet type print recording apparatus of the invention of claim 3, in the configuration of claim 1 or 2, the count value of the counting means is held when the main power supply of the apparatus is cut off. It is equipped with a backup power supply for In the above configuration, even if the main power supply of the apparatus is turned off, the count value is held by the backup power supply, so the counted ink consumption amount does not become incorrect.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which an ink jet type print recording apparatus of the present invention is embodied in a printer will be described below with reference to the drawings.

FIG. 1 is a perspective view of an ink jet printer. In FIG. 1, a manual feed unit 3 is provided in a front portion of a main body frame 2 of an inkjet printer 1, and an ink jet type of an inkjet type described later is provided on an upper portion of the main body frame 2 behind the manual feed unit 3. A carriage 9 on which the print head 10 is mounted and a sub-frame 4 including a purging device 18 and the like are mounted. A paper feed cassette 5 for storing a plurality of printing papers is provided in the upper rear part of the sub-frame 4.
Is detachably attached, and a paper ejection tray (not shown) for ejecting the printed paper is attached to the front side of the paper feeding cassette 5 so as to face the paper feeding cassette 5.

FIG. 2 is a perspective view showing the sub-frame 4, the print head 10 built in the sub-frame 4, the purging device 18, the paper feeding mechanism 19 and the like. In FIG. 2, a cylindrical platen roller 6 is arranged behind the sub-frame 4 inside. The platen roller 6 conveys the print paper supplied from the paper feed cassette 5 or the manual paper feed unit 3 while facing the print head 10, and forms a part of the paper feed mechanism 19. A pressure roller 8 is provided above the platen roller 6 to bring the printing paper into close contact with the platen roller 6. The platen roller 6 is driven via a platen gear 7 by a paper feed motor (not shown). The platen gear 7 includes one sheet of printing paper from the paper feeding cassette 5,
The drive is also transmitted to a sheet feeding gear train for feeding the platen roller 6.

Further, a carriage 9 is provided in front of the platen roller 6. The carriage 9 has a print head 10 mounted thereon and is movable along a carriage shaft 11 provided in parallel with the platen roller 6. The carriage 9 is driven by a carriage motor 12 via a belt 13. A purge device 18 is provided on the side of the platen roller 6. Since the ink jet type print head 10 may cause ejection failure due to the generation of air bubbles inside or the deposition of ink droplets on the ejection surface during its use, this is solved and good ejection is achieved. There is a purging device 18 to restore the condition. The purging device 18 is provided with a cap 15 at its tip, and when the print head 10 is covered with the cap 15, a negative pressure is generated by a pump to suck the defective ink inside the print head 10. The print head 10 is recovered. The print head 10 is provided integrally with the head unit 20, and an ink cartridge 22 that supplies ink to the print head 10 is detachably mounted on the carriage 9 together with the head unit 20.

FIG. 3 is a block diagram of a control system of the ink jet printer. The printer 1 receives the print data from the host computer via the interface 32, and performs the first control circuit 33 for developing the print data and controlling the printer, and processes the jet data for printing and other processes. And a second control circuit 34. First
The control circuit 33 includes a memory 35 that stores the received print data and the like, a CPU 36, and a PPI (parallel peripheral interface) 37 with peripheral devices. The second control circuit 34 generates the injection timing and C
A process that cannot be processed by the PU 36 is performed, and a parallel-serial conversion 38 that converts parallel ejection data into serial data based on the data transmitted from the first control circuit 33, and a dot counter that counts the number of dots from the ejection data 39 and. This second control circuit 34
Outputs the serial data, which is a command signal for ejection, a clock for synchronizing, and a print timing signal to a drive circuit 40 described later.

The printer 1 further includes a second control circuit 34.
A drive circuit 40 for driving the print head 10 in response to a signal output from the print head 10; and a print head 10 driven by the drive circuit 40 for ejecting ink from nozzles to print on a printing medium such as paper. There is. The drive circuit 40 includes a serial / parallel conversion 42 that converts serial data into parallel data, and a driver 43. Print head 10
Uses a piezoelectric element or a thermoelectric element (thermal head) as a drive source for ink ejection, receives an ink ejection command, and ejects ink supplied from an ink cartridge (not shown) from a nozzle by an inkjet method.

The dot counter 39 of the second control circuit 34 receives the serial data and the clock to count the number of jetting commands, and also receives a command from the CPU 36 to perform a predetermined counting operation to count the inks. Count consumption. Based on the count value of the dot counter 39 and the amount of ink initially filled in the ink cartridge, the CPU 3
6 is such that the remaining ink amount can be obtained. A backup power supply (battery) 44 is connected to the dot counter 39.

The first control circuit 33 has a PPI3.
A line feed motor driver 45, a carriage motor driver 46, an origin sensor 47 for detecting the origin position of the print head 10, and a paper sensor 48 for detecting the presence / absence of paper are connected to each other via 7. The line feed motor driver 45 drives the line feed motor 49 to feed the paper to the printing position and eject the printed paper.
The carriage motor driver 46 is the carriage motor 12
Drive the print head 10 mounted on the carriage.
Is moved back and forth along the paper to be printed.

The operation of the printer 1 thus constructed will be described below. When the first control circuit 33 receives print data from the host computer through the interface 32, it develops dot data based on the print data, and drives the line feed motor 49 through the line feed motor driver 45. The control as the printer is performed by controlling the sheet feeding and driving the carriage motor 12 through the carriage motor driver 46 to control the reciprocal movement of the print head 10. The second control circuit 34 converts the ejection data based on the dot data received from the first control circuit 33 into serial data by the parallel-serial conversion 38, outputs the data and the print timing signal to the drive circuit 40, and the drive circuit Reference numeral 40 converts serial data into parallel data by serial-parallel conversion 42, drives the print head 10 through the driver 43, ejects ink, and prints.

FIG. 4 and FIG. 5 show a concrete circuit configuration of the dot counter 39 and operation waveforms of respective parts. Dot counter 39
In parallel with the above printing operation, the number of ejection commands is counted to count the amount of ink consumption. Explaining the specific configuration of the dot counter 39, in FIG. 4, the dot counter 39 includes an up counter 51, an adder 52, and a constant unit 5.
3 and the serial data and the clock are input to the up counter 51 through the AND gate 54. As a result, as shown in FIG. 5, the logical product signal of the serial data and the clock is input to the up-counter 51, up-counted, and the count data corresponding to the number of ejection dots is output.

To the up counter 51, a maintenance signal output when the CPU 36 performs a maintenance operation such as cleaning the print head and a clear signal output when the ink cartridge is replaced are input. As described above, the print head 10 is capped when not in use, and is appropriately subjected to cleaning for recovering the print head 10 by forcibly sucking (purging) the defective ink inside by the operation of the purging device 18. At this time, the ink is sucked and consumed, but since this is performed regardless of the ejection data, it is necessary to add that amount to the count data in order to accurately count the ink consumption. Therefore, the constant unit 53 holds the number of dots corresponding to the amount of ink consumed for maintenance, and when the maintenance signal is input to the up counter 51, the constant unit 53 outputs the number of dots to the adder 52. Input and add to the count data. When the clear signal is input to the up counter 51, the count data is set to zero (initialization).

As described above, since the dot counter 39 outputs the count data corresponding to the number of ejected dots,
The CPU 36 can determine the remaining ink amount based on this output and the number of ejectable dots that is determined from the total amount of ink filled in a predetermined new ink cartridge that is known in advance. When the CPU 36 determines that the ink level is low, the CPU 36 turns on a warning lamp provided in the printer 1 or returns the information to the host computer to display the information to warn the user by another method. Prompt exchange.

FIG. 6 shows another concrete circuit configuration example of the dot counter 39. In this example, a down counter 61 is used instead of the up counter 51, and a selector 62, a subtractor 63, and a constant unit 53 are further provided. Serial data and a clock are input to the down counter 61 via the AND gate 54. The selector 62 selects the input to the down counter 61 from the output of the subtractor 63 or the load data which is the initial value according to the switching signal. The count data of the down counter 61 and the constant section 53 are input to the subtractor 63.

In this configuration, in order to set the initial value in the down counter 61, the selector 62 is set to the load data side by the switching command from the CPU 36, and the load data (initial value) is input. The initial value is the number of dots that can be ejected, which is determined from the total amount of ink filled in a predetermined ink cartridge. Further, at the time of maintenance operation, the maintenance signal is input to the down counter 61, and at that time, the selector 62 is switched to the subtractor 63 side, the above-mentioned number of dots is input to the subtractor 63 from the constant section 53, and the value of the subtractor 63 is input. Is output to the down counter 61. Thus the down counter 61
Then, since the number of ejected dots is sequentially subtracted from the initial value, the count data corresponds to the remaining ink amount. With this output, the remaining ink amount can be immediately obtained.
When the ink level is low, a warning can be issued in the same manner as above.

According to each of the above embodiments, the dot counter 3
Reference numeral 9 counts the number of ink dot ejection commands and determines the remaining ink amount from this and the total amount of ink filled in the ink cartridge. Therefore, a sensor for detecting the remaining ink amount is required as in the conventional case. Since the CPU 36 does not need to calculate the dot ejection number from the print data, the CPU 36 is not burdened and the processing speed does not decrease. Further, since the amount of ink consumed during maintenance of the print head 10 is also correctly counted, it is possible to accurately determine the remaining amount of ink. Further, since the dot counter 39 is provided with the backup power supply 44, even if the main power supply of the printer is cut off, the count value is not lost and is always maintained.
It can hold the correct count value.

The present invention is not limited to the configuration of the above embodiment, and various modifications can be made. For example, in the above-described embodiment, a warning or the like is output when the ink level is low. However, the degree of ink consumption may be displayed in an analog manner. Further, the printer 1 side may not have the function of dot expanding the print data, and the host computer side may dot expand the print data and send the data to the printer 1 side.

[0024]

As described above, according to the ink jet print recording apparatus of the first aspect of the present invention, the ink consumption amount is detected by counting the number of ink ejection commands, that is, the number of dots, and detecting the ink consumption amount. Since the remaining ink amount is obtained from the number of printable dots based on the total amount of ink in the ink cartridge, a sensor is not required for detecting the remaining ink amount, and the cost is low.
Therefore, the processing speed by the CPU is not adversely affected. According to the ink jet type print recording apparatus of the invention of claim 2, in addition to the above-mentioned effect, the ink amount consumed during maintenance of the print head is added to the number of ink ejection commands to count. Therefore, the more accurate ink consumption can be detected, and the accurate remaining ink amount can be known. Further, according to the ink jet type printing recording apparatus of the third aspect of the present invention, in addition to the above effects, the count value is held by the backup power source even if the main power source of the apparatus is cut off, so that the accurate ink consumption amount is improved. By the way, you can see the ink level.

[Brief description of drawings]

FIG. 1 is a schematic external view of an inkjet printer according to an embodiment of the present invention.

FIG. 2 is a perspective view of a main part of the inkjet printer.

FIG. 3 is a block diagram of a control system of the inkjet printer.

FIG. 4 is a specific circuit configuration diagram of a dot counter in a control system.

FIG. 5 is an operation waveform diagram of each part of the dot counter.

FIG. 6 is a specific circuit configuration diagram according to another example of the dot counter.

[Explanation of symbols]

 1 Printer 10 Print Head 22 Ink Cartridge 36 CPU (Control Means) 39 Dot Counter 40 Drive Circuit (Drive Means) 51 Up Counter 52 Adder 53 Constant Part 61 Down Counter 63 Subtractor

Claims (3)

[Claims] 1. A print head for ejecting ink onto a printing medium, an ink cartridge for supplying ink to the print head, control means for outputting an ink ejection command based on dot data to be printed, and the ink. An ink jet type printing recording apparatus comprising: a driving unit that drives the print head based on the ejection command of the above; and a counting unit that counts the number of ejection commands of the ink output from the control unit. An ink jet type printing recording apparatus, wherein an ink remaining amount signal can be output from a numerical value and a total ink amount of the ink cartridge. 2. The ink jet printing according to claim 1, wherein the counting unit is configured to add the amount of ink consumed during maintenance of the print head, in addition to the number of ink ejection commands. Recording device. 3. The inkjet according to claim 1, further comprising a backup power supply for holding the count value of the counting means when the main power supply of the apparatus is cut off. Print recorder.