JPH0450913B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a color ink head inspection device.

(b) Prior Art and Problems Inkjet printers have been widely used as printers for recording information output from electronic computers because they are non-impact printers, generate less noise, and are capable of high-speed recording. Incidentally, even in such inkjet printers, there is an increasing demand for color printing. A color ink head used in such a color inkjet printer has a structure as shown in FIG. That is, color ink heads 1A, 1B, 1
C, 1D are rectangular parallelepiped containers 2A, 2B, 2C, which are usually formed by welding stainless thin plates, for example.
2D, these containers 2A, 2B, 2
A nozzle hole 3 for ejecting ink at a predetermined pitch is provided on the side surface of the containers 2A, 2B, 2D.
A piezoelectric element (not shown) is installed on the upper surface of containers 2A, 2B, 2C, and 2D, and a voltage corresponding to the printed information is applied to this piezoelectric element to generate strain, and the stress of this strain is transferred to containers 2A, 2B, 2C, and 2D. The ink is transmitted to the ink chamber in the internal cavity, and the ink in the ink chamber is jetted onto recording paper (not shown) for recording. Containers 2A of the above color ink heads 1A, 1B, 1C, 1D,
The ink chambers 2B, 2C, and 2D are filled with inks of four colors: magenta, cyan, yellow, and black, respectively. Then, a voltage is applied to each piezoelectric element of the color ink heads 1A, 1B, 1C, and 1D based on the printed information, and color is injected from the nozzle holes 3 of the ink chambers of these color ink heads 1A, 1B, 1C, and 1D. Ink is ejected and the color inks are appropriately mixed on the recording paper to achieve color printing on the recording paper.

However, the method for inspecting these color ink heads involves not only inspecting the machining accuracy of the color ink heads, but also installing these color ink heads in a color inkjet printer and actually driving the color ink heads. ,
Inspect the recovery characteristics of the color ink head, such as how the ink is ejected when the device is at a low temperature, and in the case of a nozzle that ejects ink poorly, how many times the ink needs to be ejected to obtain the desired print. There is a need. Therefore, if a color ink head is installed in the device, or if a color ink head that has been inspected is found to be defective, it has to be removed from the device, adjusted, and then reattached to the device, making inspection of the color ink head time consuming.

Furthermore, conventional color ink head inspection methods only inspect whether or not ink is being ejected; inspection of the color of ink ejected onto recording paper using a color ink head relies on the naked eye. .

(c) Object of the Invention The present invention satisfies the above-mentioned needs, and allows the color recording state of print records printed using a color ink head to be changed independently without installing the color ink head in a printing device. The object of the present invention is to provide a new color ink head inspection device that can inspect the color of recorded print with high precision and good reproducibility.

(d) Structure of the Invention To achieve the above object, the color ink head inspection device of the present invention accommodates ink of a predetermined color, has nozzle holes of a predetermined pitch, and is driven based on print information. A plurality of color ink heads are provided with piezoelectric elements and are installed on a sliding shaft and move in the horizontal direction. a transparent medium to which the ink is transferred; and a light-receiving element that is disposed to face each of the color ink heads via the transparent medium and separately detects the color of the ink discharged from the nozzle hole onto the transparent medium. a light detection device that moves in synchronization with the color ink head, an ejection control circuit that operates the piezoelectric element to eject ink, a detection signal that detects the color of the ejected ink, and the ejection control circuit. It is characterized by comprising a detection means control confirmation circuit for comparing and detecting the signal sent to the circuit, and a motor drive control circuit for driving the sliding shaft of the color ink head, the transparent medium, and the light detection device. It is.

(e) Embodiment of the invention An embodiment of the invention will be described in detail below with reference to the drawings.

FIG. 2 is a block diagram showing a color ink head inspection apparatus according to the present invention, and FIG. 3 is an enlarged view of the main part of FIG.

As shown in FIG. 2, the color ink head inspection device of the present invention inspects color ink heads 11A, 11
The base 12 on which the color ink heads 11A, 11B, 11C, 11 are installed
The ink ejected from the nozzle hole 13 of D is recorded, and the color ink head 11A, 11B, 11
A transparent vinyl chloride film 14 as a transparent medium is disposed opposite to the color ink heads 11A and 11D.
Photodetecting elements 15A, 15B, 15C, 15 arranged opposite to each of 1B, 11C, 11D
Photodetector device 1 in which D is embedded in plastic resin, etc.
Consists of 6. Further, the photodetecting elements 15A, 15
As shown in FIG.
A filter 51 and a convex lens 52 that transmit only the color of the ink stored in the ink chambers in the ink chambers 1C and 11D, and a photodiode 53 that detects only the light having the wavelength of the color of the ink are embedded in plastic resin. There is.

On the other hand, as shown in FIG. 2, the base 12 on which the color ink heads 11A, 11B, 11C, and 11D are installed is installed on a sliding shaft 18 driven by a step motor 17. Move horizontally in A and B directions. Further, the transparent film 14 is moved horizontally in the direction of arrow C by a motor 19, and is also moved by a motor 20.
The rotation of the printer drives the installation stand 21 on which the film 14 is installed, and moves the film 14 up and down facing the nozzle holes 13 of the color ink heads 11A, 11B, 11C, and 11D, or Place it close to or away from it. Further, the photodetecting device 16 horizontally detects the color ink heads 11A, 11B, 11C, 1 by a predetermined pitch by driving the step motor 22.
It is designed to move in synchronization with the movement of 1D. In the figure, 23 is a motor drive control circuit that drives the step motors 17 and 22 and the motors 19 and 20, and 24A, 24B, 24
C, 24D are color ink heads 11A, 11
The color ink heads 11A, 11 are controlled by controlling the voltage applied to each piezoelectric element B, 11C, 11D.
Controls the amount of ink ejected from the color ink heads 11A, 11B, 11D.
This is an ejection control circuit that selects a nozzle hole from which ink is ejected from each of the nozzle holes 1C and 11D.
In addition, 26 in the figure is a photodetector element 15A, 15B, 15.
C, 15D are amplifier circuits that amplify the detected signals, and 27 and 28 are injection control circuits 24.
A, 24B, 24C, 24D are control circuits that control the motor drive control circuit 23, and 29 in the figure is a detection means control confirmation circuit, which is connected to the control circuits 27, 28.
injection control circuits 24A, 24B, 24C, 24
The signal sent to D and the photodetecting elements 15A, 15
Color ink head 1 by B, 15C, 15D
1A, 11B, 11C, and 11D are detected by comparing and detecting the signals of the colors of the ink discharged from 11D by an arithmetic circuit built in the detection means control confirmation circuit, and the comparatively detected signals are sent to the control circuits 27 and 28. They are starting to return.

The operation of inspecting a color ink head using the color ink head inspection apparatus of the present invention will be described.

As shown in FIGS. 2 and 3, each of the ink heads 11A, 11B, 11C, and 11D and each of the photodetecting elements 15A, 15B, 15C, and 15D are arranged facing each other with a transparent film 14 interposed therebetween. Install. Here, color ink head 1
It is assumed that the ink chambers 1A, 11B, 11C, and 11D are filled with magenta, cyan, yellow, and black ink, respectively.

Next, the control circuits 27 and 28 control the injection control circuit 2.
4A, 24B, 24C, 24D, injection control circuit 24A, 24B, 24C, 24
D to operate the color ink heads 11A, 11.
Ink is ejected onto the film 14 from nozzle holes B, 11C, and 11D. At this time, the same signal as the signal sent to the injection control circuits 24A, 24B, 24C, and 24D is also sent to the detection means control confirmation circuit 29 at the same time. Next, the photodetecting elements 15A, 15 detect the color of the ink ejected onto the film 14.
Detected by B, 15C, and 15D. For example, as shown in FIG. 3, a color ink head 11A
When the ink contained in the ink chamber is magenta, a light signal of the ink color is detected by a filter 51 that transmits only the magenta color, a convex lens 52, and a photodiode 53 that detects only the light of the magenta color wavelength. It is converted into an electrical signal, and this signal is amplified by the amplifier circuit 26. The signal amplified by this amplifier circuit is then guided to the detection means control confirmation circuit 29. On the other hand, from the control circuit 27 to the control circuit 28
injection control circuits 24A, 24B, 24C,
The same signal sent to the detection means control confirmation circuit 24D is led to the detection means control confirmation circuit 29, and this signal and the signal sent from the above-mentioned amplifier circuit 26 are added by the arithmetic circuit inside the detection means control confirmation circuit 29. The signals added by the arithmetic circuit are fed back to control circuits 27 and 28. Then, if the signal added by the arithmetic circuit inside the detection means control confirmation circuit 29 is either 0 or 1, and this signal is 1, the motor drive control circuit 23 is operated, and the color ink head 11A, 11B, 11C, 11
A step motor 1 that drives the sliding shaft 18 of D
7, and photodetecting elements 15A, 15B, 15C,
A step motor 22 that drives 15D;
The motors 19 that drive the film 14 are driven, and the color ink heads 11A, 11B,
11C, 11D and photodetecting elements 15A, 15
B, 15C, 15D and the film 14 are driven to predetermined positions, and the color ink head 11 is moved again.
Ink is ejected from A, 11B, 11C, and 11D to record on the film.

Here, the signal sent from the amplifier circuit 26 to the detection means control confirmation circuit 29 and the control circuit 2
Injection control circuits 24A, 24B, 24 from 7, 28
When the arithmetic circuit in the detection means control confirmation circuit 29 adds the signals sent to C and 24D and the signal sent to the detection means control confirmation circuit 29 and this value becomes 0, the color ink heads 11A and 11B ,11
C, 11D, the ink is not sufficiently ejected onto the film 14, or the ink of the desired color is not ejected onto the film 14, so in this case, the operation of the motor drive control circuit 23 is stopped;
Color ink heads 11A, 11B, 11C, 1
After stopping the driving of the step motor 17 for moving the film 1D and the step motor 22 for moving the photodetecting elements 15A, 15B, 15C, and 15D, and also stopping the driving of the motor 19 for driving the film 14, the control circuit 27, 28 to operate the ejection control circuits 24A, 24B, 24C, 24D, and the color ink heads 11A, 11B, 11
The ink from C and 11D is ejected onto the film 14 again, and if this state continues several times, an alarm (not shown) placed close to the motor 19 that drives the film 14 is activated to issue an alarm. If the color ink head is not working properly, readjust it again.

Further, as a modification of the color ink head inspection device of the present invention, color ink heads 11A, 11
Depending on the amount of ink ejected onto the film 14 from B, 11C, 11D, the base 21 on which the film 14 is installed is driven by the motor 20, and the film 14 is transferred to the color ink heads 11A, 11.
B, 11C, 11D, or color ink heads 11A, 11B, 11C, 11D.
In order to vary the ejection position of the ink ejected onto the film 14 from the nozzle holes, the mounting base 21 of the film 14 may be moved up and down using the motor 20.

In addition, the photodetecting elements 15A, 15B, 15C, 15
The step motor 19 that drives the film 1
4, the photodetecting element 15
Color ink head 1 is moved by moving A, 15B, 15C, and 15D in the direction perpendicular to the film 14.
A means may be provided to detect whether the ink ejected from the inks 1A, 11B, 11C, and 11D is ejected obliquely to the film 14 and readjust the position of the nozzle hole of the color ink head.

(f) Effects of the Invention As described above, according to the color ink head inspection device of the present invention, the ejection state and the color ink ejected from the color ink head can be checked without installing the color ink head in the color inkjet printer. This has the effect that the color condition of color ink, etc. can be easily inspected with high precision. It is also possible to quantitatively examine the relationship between the temperature of the room where the color ink head is installed and the amount of ink ejected, and if a satisfactory print record cannot be obtained with one ink ejection, to what extent should it be repeated? It is possible to check in advance whether a good print can be obtained when ink is ejected and the so-called recovery characteristics of a color ink head without installing it in the device.If such a color ink head inspection device is used when manufacturing a color inkjet printer, There is a lot of benefit.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the structure of a color ink head, FIG. 2 is a block diagram of a color ink head inspection apparatus according to the present invention, and FIG. 3 is an enlarged view of the main part of FIG. In the figure, 1A, 1B, 1C, 1D, 11
A, 11B, 11C, 11D are color ink heads, 2A, 2B, 2C, 2D are containers, 3, 13 are nozzle holes, 12, 21 are bases, 14 is a film,
15A, 15B, 15C, 15D are photodetecting elements,
16 is a photodetector, 17 and 22 are step motors, 18 is a sliding shaft, 19 and 20 are motors, 23 is a motor control drive circuit, 24A, 24B, 24C,
24D is an injection control circuit, 26 is an amplifier circuit, 27,
28 is a control circuit, 29 is a detection means control confirmation circuit,
51 is a filter, 52 is a convex lens, 53 is a photodiode, A and B are arrows indicating the moving direction of the sliding shaft, and C is an arrow indicating the moving direction of the film.

Claims (1)

[Claims] 1 A plurality of color inks that house ink of a predetermined color, have nozzle holes of a predetermined pitch, are equipped with a piezoelectric element that is driven according to print information, and are installed on a sliding shaft and move in the horizontal direction. a transparent medium disposed opposite to the color ink heads and moving in vertical and horizontal directions to transfer ink from the color ink heads, and facing each of the color ink heads through the transparent medium; a photodetecting device that is arranged and installed and includes a light receiving element that separately detects the color of the ink ejected from the nozzle hole onto the transparent medium and moves in synchronization with the color ink head; and the piezoelectric element. an ejection control circuit that operates to eject ink, a detection means control confirmation circuit that compares and detects a detection signal that detects the color of the ejected ink and a signal sent to the ejection control circuit, and a slider of the color ink head. A color ink head inspection device comprising a motor drive control circuit for driving a moving shaft, a transparent medium, and a photodetector.