KR0149764B1 - The device for preventing discharge of no-marking paper for page printer - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a page printer, and more particularly, to a blank paper output leaving apparatus of a printer for preventing continuous output of blank paper.

2. The technical problem to be solved by the invention

SUMMARY OF THE INVENTION An object of the present invention is to provide a blank paper output preventing device of a printer for stopping the output of a paper by detecting it when the paper output from the page printer is continuously output in a blank paper state.

3. Summary of Solution to Invention

LD data applied to the LSU is input from an engine control unit, and the AND gate is used to logically compare the LD data with the horizontal synchronous signal applied from the LSU. If there is no change in the output signal of the AND gate continuously for a page or a predetermined number of pages, it is detected that there is an abnormality in the LD data and the driving of the engine control unit is stopped. The output of the blank sheet is stopped by the drive control of the engine control unit.

4. Important uses of the invention

This can be useful for a page printer for printing image data onto a recording medium.

Description

Blank paper output prevention device of page printer.

1 is a block diagram of an electrophotographic developing laser beam printer according to the present invention.

2 is a control signal transmission and reception diagram between a video controller and an engine controller.

3 is a flow chart illustrating a print output control of an engine controller according to an exemplary embodiment of the present invention.

4A and 4B are operation timing diagrams of a control signal according to the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a page printer, which is an image recording apparatus, and more particularly, to an apparatus for preventing the output of a blank sheet of a page printer for preventing the output of a blank sheet generated during printing.

In general, a page printer refers to a printer that receives image data of one page unit and prints on paper, which is a recording medium. As a conventional page printer, an electrophotographic developing laser beam printer can be exemplified. Usually, a laser beam printer is composed of a video controller and a print engine unit. The video controller converts the data code received from the host computer into image data that can be processed by the print engine, and transmits the data code to the print engine unit in units of pages. The print engine unit controls the printer engine to print image data in units of pages transmitted from the video controller on a sheet of paper. On the other hand, when a video controller of a conventional laser beam printer receives a data code to be printed from a host computer, it first determines whether the data code is a control code, and if it is not a control code, considers it as a data code and transmits it to the print engine unit. In the print engine unit, a laser diode of a LUS (Laser Scanning Unit: LSU) is driven in response to the data code transmitted from the video controller. However, when an error occurs in the laser beam printer or an undefined data code is received from the host computer, when the sheet is fed out, the printer continuously outputs a blank sheet.

Accordingly, an object of the present invention is to provide a blank paper output prevention device of a printer for stopping the output of the paper by detecting the paper output from the laser beam printer continuously output in the blank state.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description the same components have been given the same reference numerals and also many specific details such as specific processing flows are shown to provide a more general understanding of the invention. It will be apparent to those skilled in the art that the present invention may be practiced without these specific details. And a detailed description of known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

1 is a block diagram of a laser beam printer according to the present invention, wherein an abnormal data detection unit 44 for implementing the present invention is provided between an engine control unit 34 and an LSU 42 of a conventional laser beam printer. It is connected and configured. Referring to FIG. 1, the laser beam printer includes a video controller 20, a print engine unit 30, an OPE 28, and an abnormal data detector 44, while the video controller 20 has a computer interface. And a video control unit 24 and an engine interface 26. The computer interface 22 is connected between the host computer and the video control unit 24 to interface the input and output signals. The video controller 24 includes a ROM having a control program, a OPE 28, and a RAM for temporarily storing various data input from a host computer, and the data code received from the computer interface 22. The image is converted into image data that can be processed by the printer engine and transmitted to the print engine unit 30. The engine interface 26 interfaces an input / output signal with the print engine unit 30 under the control of the video control unit 24. On the other hand, the OPE 28 includes a plurality of keys for inputting various commands and a display device for displaying information according to the operation of the printer when controlled by the video controller 24. The print engine unit 30 includes a video interface 32, an engine controller 34, an input / output (I / O) interface 36, a sensor circuit 38, a mechanism driver 40, and an LSU 42. And is connected to the video controller 20. The video interface 32 provides an interface for transmission and reception signals between the video controller 20 and the engine controller 34. The engine control unit 34 controls the mechanical drive unit 40 and the LSU 42 under the control of the video controller 20, and prints an image according to the image data received from the video controller 20 on paper. At this time, the engine control unit 34 converts the image data into LD data signals synchronized with horizontal and vertical signals and applies them to the LSU 42. In addition, the engine control unit 34 detects an operation state (for example, paper feeding and conveying state, developer amount, etc.) of each part of the print engine unit 30 through the sensor circuit 38. The I / O interface 36 is connected between the engine control unit 34, the sensor circuit 38, the mechanical drive unit 40, and the LSU 42 to interface the input / output signals of the engine control unit 34. The sensor circuit 38 drives various sensors for detecting the operation state of each part of the print engine unit 30, the paper feeding and conveying state, the developer amount, and the like, and the detection signal of each sensor is transmitted to the engine control unit 34. to provide. The mechanism driver 40 drives various mechanisms for feeding, feeding and printing paper sheets under the control of the engine controller 34, while the LSU 42 controls the laser beam according to the image data under the control of the engine controller 34. Is generated to expose a photosensitive drum (not shown) to form an electrostatic latent image on the photosensitive drum. The abnormal data detector 44, which normally uses a watch dog, receives a horizontal sync signal Hsync from the LSU 42 and receives an LSU (LSU) from the engine controller 34 through the I / O interface 36. 42. The LD data signal applied to the LD data signal is input to compare the logic state of the horizontal synchronous signal included in the LD data signal with the horizontal synchronous signal input from the LSU 42 to the engine controller 34 when an abnormality of the LD data signal is detected. Apply the interrupt signal.

FIG. 2 is a diagram illustrating a transmission / reception relationship of control signals between the video control unit 24 and the engine control unit 34 through the I / O interface 36. FIG. 4A shows an operation timing diagram according to an active state of the control signals. . 2 and 4A, when the power supply of the laser beam printer is turned on, the engine control unit 34 initializes each part of the printer system and then sends a ready signal to the video control unit 24. Send a message to notify the ready state of the printer engine. Thereafter, the video controller 24 prints a signal indicating the print command to the engine controller 34 when there is a print command from the host computer. Send the. In addition, the engine control unit 34 transmits a page synchronization request signal to the video control unit 24. The video control unit 24 sends the page synchronization request signal. Page sync signal in response to Is sent to the engine control unit 34. Meanwhile, in FIG. 2, the engine control unit 34 converts the image data ID received from the video control unit 24 into LD data signals synchronized with horizontal and vertical signals, and applies them to the LSU 42. The operation timing chart according to the LD data is as shown in FIG. 4A. In the LD data of FIG. 4A, A and B indicate that there is no LD data when the data period is logical high (dotted line).

4b shows a timing diagram of the horizontal synchronization signal HSYNC applied to the abnormal data detection unit 44 and the LD data applied to the LSU 42 from the engine control unit 34. In order to explain the exemplary embodiment of the present invention, the LD data indicates that there is LD data in section C and that there is no LD data in section D. In addition, since the LD data is horizontally synchronized by the engine control unit 34, the LD data includes a horizontal synchronization signal.

3 is a control flow diagram of the engine control unit 34 for controlling the output of the paper by detecting the paper when the paper blank is continuously output according to the present invention, and referring to FIGS. 1 to 4b below. The control process for preventing the output will be described.

In FIG. 3, when the driving power of the laser beam printer is concealed to print predetermined data on paper as a recording medium, the engine control unit 34 initializes each unit of the print engine unit 30 in step 60 and then step 62. Proceed to In step 62, the engine controller 34 prints a signal from the video controller 24. Checks whether is entered. When there is a print signal input in step 62, the engine controller 34 proceeds to step 64 and converts the image data ID input from the video controller 24 into horizontally and vertically synchronized LD data and outputs it to the LSU 42. do. At this time, the abnormal data detector 44 inputs the LD data and outputs an active interrupt signal to the engine controller 34 when the LD data is abnormal data. Hereinafter, the operation of the abnormal data detecting unit 44 will be described with reference to FIG. 4B. Since the LD data applied to the LSU 42 includes the horizontal synchronous signal HSYNC, the abnormal data detector 44 uses an AND gate to remove the horizontal synchronous signal HSYNC. That is, while the LD data and the horizontal synchronizing signal HSYNC are logic low for the same time, the AND gate output signal AGOS (And Gate Output Signal: AGOS) is maintained at the logic low state, and the horizontal synchronizing signal HSYNC is at the logic high state. When the logic of the LD data changes to a high or low state, the output of the AND gate changes according to the logic state of the LD data. In other words, the output signal AGOS of the AND gate is changed from logic high to low to high in section E. Since the logic change of the AND gate output signal AGOS indicates that there is LD data, the abnormal data detection unit 44 does not generate an interrupt signal to the engine control unit 34. On the other hand, in section D indicating no LD data, the output signal AGOS of the AND gate remains logic high for the section F. Page sync signal after the F section If the output signal AGOS of the AND gate continues to be logic high until is activated, the abnormal data detection unit 44 outputs an interrupt enable signal to the engine control unit 34. Thereafter, in step 66, when there is an input of the interrupt enable signal from the abnormal data detection unit 44, the engine controller 34 proceeds to step 68 and transmits a print error signal to the video controller 24 through the engine interface 26. After printing, finish printing. Therefore, the output of the white paper continuously output can be stopped and the video controller 24 controls the display device provided on the OPE 28 in response to the reception of the print error signal to inform the printer user of the print error situation. Notify.

As described above, the present invention can control the operation of the print engine unit by detecting the continuous output of the white paper which may occur due to the abnormality of LD data applied to the LSU from the engine control unit, thereby preventing the continuous output of the white paper. There is this.

Claims (2)

In the blank paper output prevention device of a page printer, it is a general control operation of the page printer and converts the data code received from an external device into image data that can be processed by the engine of the page printer, and then converts it into engine control means. A video control means for outputting in units of pages, and an engine mechanism of the page printer to print page data of the page unit received from the video control means on a sheet, and image data in units of pages received from the video control means. Engine control means for horizontally and vertically synchronously outputting the light to the light source means, and generating a light source according to the page data applied from the engine control means to expose the photosensitive drum to form an electrostatic latent image on the photosensitive drum. Signal Inputting the light source means output to the abnormal data detection means and image data in units of pages applied to the light source means from the engine control means to detect the presence of abnormal data, and active as the engine control means when the abnormality of the image data is detected. Blank paper output prevention device of a page printer, characterized in that it comprises an abnormal data detection means for outputting the interrupt signal of the state to prevent the output of the blank paper The interrupt signal of claim 1, wherein the abnormal data detecting unit detects an abnormality of image data in units of pages applied from the engine control unit to the light source unit and continuously detects abnormality of the image data. Paper sheet output prevention device of a page printer, characterized in that for outputting.