JPH01316284A - Printer equipped with printing density detection mechanism - Google Patents

Abstract

PURPOSE:To remove trouble someness such as judging density by a human naked eye by preliminarily determining a ratio of a black area of a character to be printed to the black area of the character printed on a medium. CONSTITUTION:A medium 1 is printed with a printing head 6 from a printing part 12. A sensor 2, a data inputting lamp 4, and a roller are controlled by a conveyor part 9 and an image input part 10. A printed image data on the medium is irradiated with the data inputting lamp 4. The image data inputted to the sensor 2 is inputted to a memory annexed to the image input part 10. For the inputted image data, a light and shade judging part 11 obtains a ratio of a detected black area to a black area detected from the preliminarily printed image data. When this value is lower than a preliminarily determined value, a part of the printed character is judged to be notched, and a density decrease alarm signal is outputted. When it is detected to be faint with the light and shade judging part 11, indication to an indication element to be connected to the control part 2 and notification to a higher rank device are performed, and inspection of the density after printing is automatically executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printer with a print density detection mechanism, and more particularly to a printer with a print density detection mechanism that warns when to replace an ink ribbon.

[Conventional technology]

Conventional printers do not have a print density detection function, and the time to replace the ink ribbon is determined by human visual density detection.

[Problem to be solved by the invention]

The conventional Bunrita mentioned above does not have a function to detect print density, and the only way to determine when to replace the ink ribbon is by recognizing the decrease in print density by the number of printed characters or by human visual inspection. There is a drawback that the print density becomes uneven when replaced.

[Means to solve the problem]

The print density detection device of the present invention includes at least an image input means for detecting black area information of characters printed on a medium;
A printing unit that prints on a medium and outputs black area information of the printed characters, and a ratio of the black area detected by the image input means to the black area of the characters printed by the printing unit is determined in advance. and a light/darkness determining means that sends out a density reduction warning signal when the density falls below a certain value.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. In this embodiment, a medium 1 to be printed, a sensor 2 for inputting an image on the medium, and a connection between the medium 1 and the sensor 2 are shown. a guide 5 that keeps the medium 1 at a constant distance, a rotatable roller 3 that presses the medium 1 against the guide, a data input lamp 4 that illuminates the medium 1, a print head 6 and a platen 7, and a conveyor that transports the medium. 9, an image input section 10 that inputs an image of the medium through the sensor 2, a density determination section 11 that detects and determines the density of the input image, and a printing section 12 that prints on the medium and outputs the information. , and a control section 8 that performs overall control.

The medium 1 is printed by the print head 6 from the printing unit 12,
The sensor 2, the data input lamp 4, and the roller 3 are controlled by the conveyance unit 9 and the image input unit 10, and the image data printed on the medium is irradiated onto the data input lamp 4, and in this state is input to the sensor 2. The image data obtained is input to a memory attached to the image input section 10.

The shading determination unit 11 uses the input image data to determine whether the detected black area (an area of data such as characters may be divided into meshes and the number of meshes that are black can be calculated) is determined by the corresponding (character) printed in advance. ) Calculate the ratio to the black area detected from the image data (which can also be considered the character) If this value is less than a predetermined value, part of the printed character is missing ( That is, it is determined that the density of the image data printed on the medium 1 is light), and a density reduction warning signal is output.

If the density determination unit 11 detects that the print is light, the density can be automatically detected after printing by displaying the image on the display element connected to the control unit 2 and notifying the host device.

〔Effect of the invention〕

As explained above, the present invention enables density determination by human visual observation by predetermining the ratio of the black area of the characters to be printed (image data) to the black area of the characters (image data) printed on the medium. It has the effect of eliminating tired lines.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. 1... Medium, 2... Sensor, 3... Roller, 4...
... Data input lamp, 5... Guide, 6... Print head, 7... Platen, 8... Control unit, 9...
- Conveyance section, 10... Image input section, 11... Shade determination section, 12... Printing section.

Claims (1)

[Claims] At least, an image input means for detecting black area information of characters printed on a medium, a printing section for printing on the medium and outputting black area information of the printed characters, and an image input means for detecting black area information of the printed characters. and a density determining means for transmitting a density reduction warning signal when the ratio of the black area of the printed character to the black area of the character printed by the printing section becomes less than a predetermined value. A printer with a detection mechanism.