JP2690076B2 - Recording device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a word processor, a computer aided design system (hereinafter abbreviated as CAD), and a computer aided manufacturing system (hereinafter abbreviated as CAM). The present invention relates to a recording device used as an output device of characters and images of a data processing device such as. BACKGROUND ART In recent years, with the development of computers, word processors,
The spread of CAD, CAM, etc. is remarkable. The conventional recording device will be described below. FIG. 5 is a cross-sectional view of a main part of a conventional recording apparatus. Reference numeral 18 is a photosensitive drum having a photosensitive layer (not shown in the drawing) formed on its surface and rotating in a direction indicated by an arrow A, and 19 is a center. A charging line 19a is disposed on the charging line 19a to charge the photoconductor drum 18, and the charging device 19 has an elongated frame shape as shown in more detail in FIG. 20 is a laser unit that generates laser light and modulates the laser light according to recorded information, 21 is a reflecting mirror that changes the direction of the laser light,
22 is a developing device, 23 is a developer, a roller 24 is disposed inside the developing device 22, and a magnet is further provided inside the roller 24.
25 is arranged, the roller 24 rotates in the direction indicated by the arrow B, the developer 22 is held in a frictionally charged state, and the blade
An appropriate amount leaks from 26 and is supplied to the photosensitive drum 18. 27 is a paper feed roller which rotates in the direction shown by arrow C, 28 is a recording paper, 29 is a transfer device in which a charging line 29a is arranged in the center, and 30 is a cleaning device having a cleaning blade 31 which contacts the photosensitive drum 18 inside. And 32 is a static eliminator, and 33 is an eraser lamp arranged inside the static eliminator 32. FIG. 7 is a perspective view of a conventional recording apparatus. 34 is the entire recording apparatus, 35 is a paper cassette, 36 is a power switch, and 37 is a density adjusting knob. The operation of the conventional recording apparatus configured as described above will be described below. First, the photosensitive drum 18 rotates in the direction indicated by the arrow A, and the charger 19 charges the surface of the photosensitive drum 18 to a uniform potential. Next, the laser unit 20 generates laser light modulated according to recording information sent from a connected computer (not shown in the figure), scans the photoconductor drum 18, and causes the photoconductor drum 18 to scan. Form an electrostatic latent image. Next, the developing device 22 causes the developer 23 to adhere to the electrostatic latent image, and the development is performed. At this time, the roller
A developing bias current is applied to 24, and the developer 23 adheres to the photosensitive drum 18 due to the potential difference from the electrostatic latent image.
The recording paper 28 is conveyed by the paper feed roller 27 and comes into close contact with the photosensitive drum 18 on which the developed image is formed, and the developer 23 is attached to the recording paper 28 by the transfer device 29. The developer 23 adhering to the recording paper 28 is fixed by a fixing device (not shown in the figure), and becomes the final printed matter. The density of printed characters and images (hereinafter abbreviated as ID) can be changed by the density adjustment knob 37. The density adjusting knob 37 is provided to prevent the density from decreasing in response to a decrease in the residual amount of the developer 23. When you operate the density adjustment knob 37,
The voltage value and current value of 19a are changed to change the charging potential on the photoconductor drum 18, the light intensity of the laser unit 20 is changed to change the potential of the electrostatic latent image, and the development of the developing device 22 is performed. The density of the printed matter can be changed by changing the bias current. In addition to the above-mentioned purpose, the density adjusting knob 37 performs low density recording so as not to fill a space between lines when recording only with characters (hereinafter referred to as fine line reproducibility). When printing an image such as a photograph, it is also used for high density recording so as to prevent uneven density. Problems to be Solved by the Invention However, in the above-described conventional configuration, the density adjustment knob 37
Is unrelated to the data sent from computers, etc.,
If you want to change the density of images such as letters and photos from the outside, you have to operate the density adjustment knob 37 after each recording, which is a complicated operation. On the other hand, when images such as characters and photographs are recorded on one sheet of recording paper, the user has to decide which image is more important, which is a heavy burden on the user. . Further, when the recording apparatus is connected to a large number of computers, it is necessary to confirm the position of the density adjusting knob 37 every time the user changes, which causes a problem that the operation becomes complicated. In addition, in the case of continuous recording in which images of images such as photographs and characters that explain them are mixed, high density recording is performed in order to prevent uneven density in the photographs, but the characters are also high at this time. Since the recording is performed with the density, there is a problem that the consumption amount of the developer increases. In addition, if the user determines that an image such as a graph is the same as an image such as a photograph and adjusts the density so as to record at a high density, the reproducibility of fine lines is deteriorated and the image quality is deteriorated. Means for Solving the Problems According to the present invention, if the density of dots recorded based on data indicates whether the transmitted data is mainly composed of characters or mainly images It is provided with a judging means for judging that the character is the main constituent, and for judging that the character is the main character when the character does not exceed, and a recording means for setting the recording density according to the output of the judging means and recording. The recording density of the recording means is set to be light when the image data is mainly composed of characters, and is set to be dark when the image data is mainly composed of the image. Operation With the above configuration, it is not necessary for the user to judge the content of the image to be recorded and adjust the density, and the density can be adjusted automatically and reliably. Further, when the density of the dots printed based on the data exceeds a certain value, the judging means judges that the data is mainly an image, and the recording means records with high density, and the dot density of the graph is low. For the image, it is determined that the data is mainly composed of characters, and the recording unit can perform recording with low density. Embodiment FIG. 2 is a cross-sectional view of a main part of a recording apparatus according to an embodiment of the present invention, in which 18 is a photosensitive drum, 19 is a charger, 20 is a laser unit, 21 is a reflecting mirror, 22 is a developing device, and 23. Is a developer
24 is a roller, 25 is a magnet, 26 is a blade, 27 is a paper feed roller, 28 is a recording paper, 29 is a transfer device, 30 is a cleaning device,
Reference numeral 31 is a cleaning blade, 32 is a static eliminator, and 33 is an eraser lamp, which have the same configuration as the conventional example. FIG. 1 is a circuit block diagram of the present embodiment, where 1 is the whole recording apparatus, 2 is a host computer connected to the outside of the recording apparatus 1 and transmitting recording information, and 3 is recording information in page units. A controller section for editing the controller section 4, a microprocessor for controlling the controller section 3, 5 an interface section for receiving recording information transmitted from the host computer 2, 6 a program storage section for storing the program of the microprocessor 4, and 7 Is a font storage unit that stores fonts corresponding to character data, 8 is a page memory that stores data of characters and images laid out in page units, and 9 is input parallel data that is output after being converted into serial data. A parallel-serial conversion unit, 10 is an engine unit for recording, and 11 is a microprocessor for controlling the engine unit 10. Reference numeral 12 denotes a light source drive unit that drives the light source 13 in the laser unit 20, 14 is a density control unit that controls the light source drive unit 12 according to a command from the microprocessor 4 and controls the recording density, and 15 is an input of various sensors. Is a sensor input unit, 16 is a mechanism control unit that controls the photosensitive drum 18 and the like, and 17 is a mechanism unit composed of components as shown in FIG. The operation of the recording apparatus of this embodiment configured as described above will be described below with reference to the flowchart of FIG. First, when the record information is transmitted from the host computer 2, the interface unit 5 receives the record information and outputs the record information to the microprocessor 4 (step a). Next, the microprocessor 4 determines whether the sent record information is image data or character data (step b). The character data is an American standard code (hereinafter,
Abbreviated as ASCII code. ) And the image data is transmitted as a bit image, this determination is easily performed. Next, when the print information is image data, the microprocessor 4 calculates the print area occupied by the sent image data (step c). If the recorded information sent is image data, the font storage unit 7
The font of the character corresponding to the ASCII code is read out (step d), and the area occupied by the character data is calculated (step e). Next, the character data and the image data are stored in the page memory 8 which stores the states of the dots corresponding to all the recorded images (step f). When the storage in the page memory 8 is completed (step g), the area occupied by the image data and the area occupied by the character data are compared (step h). When the area occupied by the image data is large, the microprocessor 4 instructs the microprocessor 11 that controls the engine unit 10 to perform recording with a high image recording density (step i). If the area occupied by the character data is large, the microprocessor 4 instructs the microprocessor 11 which controls the engine unit 10 to perform recording with a low character recording density (step j). At this time, the microprocessor 11 outputs a signal corresponding to the recording density to the density control means 14, and the density control means 14 controls the light source 13 so that the light intensity corresponds to the recording density.
Next, the microprocessor 11 controls the mechanical section according to the data stored in the page memory 8 to perform recording at a density corresponding to the recording density. FIG. 3 is a graph showing the relationship between the recording density and the consumption amount of the developer, in which the vertical axis represents the recording density ID and the horizontal axis represents the consumption amount of the developer when recording is performed at that density. In the recording apparatus according to the present exemplary embodiment, ID is 1.2 when the image recording apparatus performs recording, and the developer consumption amount B is obtained. At this time, there is no density unevenness during solid black recording, but the fine line reproducibility is poor. Note that
In the vicinity of ID = 1.2, the slope of the curve is almost horizontal, so the developer consumption amount C hardly changes to ID = 1.2. Further, when recording is performed with the character recording density, the developer consumption amount A is ID = 1.0. At this time, the amount of developer consumed is smaller than that when recording is performed at the image recording density, and fine line reproducibility is good, but density unevenness easily occurs during solid black recording. As described above, since the consumption of the developer is smaller when recording is performed at the character recording density, whether to perform the recording in which the character is emphasized from the record information as in the present embodiment or the image is emphasized. By performing judgment and recording, the amount of developer consumption can be brought close to the optimum value, and efficient recording can be performed. In this embodiment, whether the character data is important or the image data is important is determined by comparing the areas occupied by the respective data. It is effective when it is required that there is no unevenness in density or density. However, even if the image data is sent as a bit image, it is not effective in the case of an image having many lines such as a graph including a large amount of characters because the fine line reproducibility is poor. For this reason,
It is more effective to compare the character data and the image data by not only comparing the area ratios but also calculating the average dot density of the image data and performing high density recording when the value exceeds a certain value. is there. EFFECTS OF THE INVENTION The present invention determines that the image is mainly used when the density of the dots recorded based on the data indicates whether the sent data is mainly characters or images. Judgment means for judging that the character is the main character if it does not exceed, and recording means for setting the recording density according to the output of the judgment means and recording, and judging the content of the image to be recorded by the user, Since it is not necessary to adjust the density and the density can be adjusted automatically, the operation of the entire recording device can be simplified, and high density recording is performed only when it is determined that the image is the main object. The consumption amount of the developer can be brought close to the optimum value. Further, the judging means judges that the data is mainly an image when the density of the dots recorded based on the data exceeds a certain value, and the character is the data for the image such as a graph having a low dot density. Since it is judged to be the main subject, it can be surely judged whether it is an image or a character for any image data, and surely an appropriate density adjustment is made for characters, graphs, photographic images, etc. High quality recording is possible.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a circuit diagram of a recording apparatus according to an embodiment of the present invention,
FIG. 2 is a sectional view of the same main part, FIG. 3 is a graph showing the relationship between the recording density and the amount of developer consumed, FIG. 4 is the same flowchart, and FIG. 5 is a sectional view of the main part of a conventional recording apparatus. FIG. 6 is a perspective view of the charger, and FIG. 7 is a perspective view thereof. 3 ... Controller section, 4 ... Microprocessor, 5 ... Interface section, 6 ... Program storage section, 7 ... Font storage section, 8 ... Page memory, 9 ... Parallel-serial conversion section, 10 ... Engine part, 11 ... Microprocessor, 12 ... Light source drive part, 14 ... Concentration control means, 15 ... Sensor input part, 16 ... Mechanism control part, 17 ... Mechanism part

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Takanori Tsuji               1006 Kadoma Kadoma Matsushita Electric Industrial               Inside the corporation                (56) References JP-A-61-2471 (JP, A)                 JP-A-60-194472 (JP, A)

Claims (1)

(57) [Claims] If the density of dots recorded based on this image data exceeds a certain value, it is judged that the image is the main image, and whether the image data sent is mainly composed of characters or images. A recording apparatus comprising: a judgment unit that judges that a character is a main body when there is no character; 2. The recording density of the recording unit is set to be light when the image data is mainly composed of characters, and is set to be dark when the image data is mainly composed of the image. The recording apparatus according to claim 1.