JPH07135572A - Image forming system - Google Patents

Abstract

PURPOSE:To reduce the capacity of a storage means for image forming as less as possible without need of a special interface between a host device and an image forming device by adding color information of bit data to be sent before bit data of each color in the case of transmission and storing bit data for each color based on the color information in the storage means provided in the image forming device. CONSTITUTION:The system is provided with a host device converting color picture data into bit data for each color and sending the converted data to an image forming device 2 and the image forming device 2 receiving the bit data for each color and generating a printed matter. Then color information of the bit data to be sent is added before the bit data for each color in the case of transmission of the bit data for each color from the host device 1 and the bit data for each color are stored in a storage means provided in the image forming device 2 based on the color information. Thus, it is not required to transfer data for each color page and then the memory capacity is reduced.

Description

Detailed Description of the Invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention converts a color image data into bit data for each color and transmits the bit data to an image forming apparatus, and a bit data for each color received from a host device. The present invention relates to an image forming system including an image forming apparatus that generates a printed matter.

[0003]

2. Description of the Related Art Conventionally, an image forming system in which image data is converted into bitmap data on a host device and the image forming device performs an image forming operation based on the bitmap data from the host device. It has been known.

[0004]

However, in such a conventional image forming system, in order to match the printing speed of the image forming apparatus, specifically, the optical writing speed to the photoconductor,
It has been necessary to equip the image forming apparatus with a high-capacity storage means for each color between the high-speed interface host apparatus and the image forming apparatus. Therefore, the present invention does not require a special interface between the host apparatus and the image forming apparatus, makes the capacity of the storage unit of the image forming as small as possible, and enables a normal image forming operation. It is an object of the present invention to obtain an image forming system for

[0005]

To achieve the above object, the present invention is directed to a host device for converting color image data into bit data for each color and transmitting the bit data to an image forming apparatus, and a host device for each color. In an image forming system equipped with an image forming apparatus for receiving bit data for each color from a host device to generate a printed matter, when transmitting the bit data for each color from the host device, before the bit data for each color The color information of the bit data to be transmitted is added, and the bit data for each color is stored in the storage means corresponding to each color provided in the image forming apparatus based on the color information.

Further, the receivable upper state of each storage means is detected based on the remaining storage capacity of the storage means for each color provided in the image device, and the type of bit data received by the image forming apparatus is determined. Is configured to.

Then, based on the amount of data already stored in the storage means provided in the image forming apparatus and the printing speed of the image forming apparatus, the amount of data already stored in the storage means is insufficient. If it is determined that the amount of data is insufficient, the color of the insufficient bit data is designated and a transmission request is made to the host device.

Further, when the storage means corresponding to at least two colors in the storage means for each color are in a receivable state, priority is given to each color to be received.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. FIG. 1 schematically shows an image forming unit of an image forming apparatus in an image forming system according to an embodiment of the present invention. FIG. 2 is a block diagram of a data receiving unit of the image forming apparatus in the image forming system according to the embodiment of the present invention. FIG. 3 is an external configuration diagram of an image forming system according to an embodiment of the present invention.

The image forming system of the present invention comprises a host device 1 and an image forming device 2. In the image forming unit of the image forming apparatus 2, after the photoconductor 3 is uniformly charged by the charging device 8, optical writing 4, 5 corresponding to each color is performed.
By developing this for each color, toner is applied to the photoreceptor.
An image is formed. This is transferred by a transfer unit 9 onto a sheet fed from a sheet feeding unit (not shown), and then the sheet is conveyed to a fixing device. The embodiment shown in FIG. 1 shows an image forming apparatus capable of obtaining printed matter of two colors, black and red.

When the image data formed by the host device 1 such as a document is output from the image forming device as a printed matter, the image data on the host device 1 side is printed in each color by a conventionally known method. It is converted into bit data for each and the bit data is transmitted to the image forming apparatus.

As a method of transferring bit data, a time T = L / V for moving the photosensitive member from the black light writing position 4 to the red light writing position 5 (L: distance of light writing position, V:
Within the rotation speed of the photoconductor, if the transmission of all the black bit data written first has not been completed and the transfer of the red bit data has not started, the black and red data are simultaneously transferred. Therefore, two colors must be written on the photoconductor 3 at the same time. The timing chart at this time is shown in FIG.

In order to write two colors simultaneously, bit data of two colors are mixed and transmitted at the same time when data is transferred. At this time, since there is no color information in the bit data, information indicating color information is added to the header part of the bit data.

FIG. 5 shows a time chart for black data transfer as an example. When it is desired to transmit black bit data, first, the host device transmits a data transfer request signal to the image forming apparatus. This is received by the host interface and this information is sent to the selector. The state of the black reception buffer 13 is confirmed by this selector, and when the data reception is possible, the black data reception ready signal is transmitted to the host device. When the host device can receive this black data reception ready signal, the black data is transferred from the host side. The signal sent from the printing device side is
The selector determines that the data is black data and writes it in the black reception buffer 13. When transmitting bit data in a mixed manner, data transfer requests for black data and red data are alternately transmitted to perform data transfer.

FIG. 6 is a timing chart showing an operation related to claim 2 of the claims.

When the image forming apparatus receives the black data transfer request signal, the selector 12 of the receiving section detects the amount of data in the black receiving buffer 13. At this time, the amount of data that is sufficiently in time for the optical writing is the black reception buffer 1
If it is 3, the state of the red reception buffer 14 is checked by the selector. If the amount of red data is small, not the black data reception ready signal but the black data reception busy signal indicating the transfer disapproval. Is transmitted to the host device side, a red data reception request signal is transmitted to the host device, and red bit data transfer is performed.

FIG. 7 is a timing chart showing an operation related to claim 3 of the claims.

When receiving black data, the selector checks the red reception buffer 14 at a certain fixed timing. At this time, if it is determined that the red data is insufficient at the optical writing timing, the red data reception request signal is transferred to the host device 1.

On the side of the host device 1 receiving this signal,
Transmission of black data is stopped and red data is sent to the image forming apparatus 2.
By outputting a data transfer request signal, the red data data transfer operation is performed.

FIG. 8 is a flow chart showing an operation corresponding to claim 4 of the claims, and FIG. 9 is a timing relating to an operation corresponding to claim 4 of the claims. It is a chart.

In an image forming apparatus capable of printing four colors of yellow, magenta, cyan and black, when the host device outputs a yellow data transfer request signal, the selector selects yellow (Y) and magenta ( M), cyan (C), and black (B) data reception buffers are examined to detect the amount of data, the amounts of data in the four buffers are compared, and the relationship between these and the optical writing timing is detected. The priority order of data reception of each color is determined according to, and the data reception request signal is transmitted to the host device 1 from the highest priority order.

The host device 1 side outputs a data transfer request for the highest priority data and transfers the data. Also,
This processing is performed every certain number of times the data transfer request signal is transmitted from the host device 1.

[0023]

As described above, according to the first aspect of the present invention, when data is transmitted and received, it is possible to mix and transmit each color so that each page of each color is transmitted. It is not necessary to transfer data, it is possible to reduce the memory amount, increase the rotation speed of the photoconductor,
The image forming speed can be improved. According to the second aspect of the invention, when the bit data is received, the data transfer is performed from the bit data that is likely to be insufficient, so that normal image formation can be performed. Further, according to the third aspect of the invention, an error is generated before the bit data runs short.
Can be avoided. In the invention described in claim 4, the normal image forming operation can be performed by supplementing the data which is likely to run short of data during the printing process.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an outline of an image forming unit of an image forming apparatus in an image forming system according to an embodiment of the present invention. FIG. 2 is a block diagram of a data receiving unit of the image forming apparatus in the image forming system according to the embodiment of the present invention. FIG. 3 is an external configuration diagram of an image forming system according to an embodiment of the present invention. FIG. 4 is a timing chart showing the optical writing timing according to the embodiment of the present invention. FIG. 5 is a timing chart showing the transfer timing of black bit data. FIG. 6 is a timing chart showing the operation timing of one embodiment of the invention of claim 2. FIG. 7 is a timing chart showing the operation timing of one embodiment of the invention of claim 3. FIG. 8 is a flow chart showing the operation of the embodiment of the invention of claim 4. Figure 9
Is a timing chart showing the operation timing of one embodiment of the invention of claim 4.

[Explanation of symbols]

 1 Host Device 2 Image Forming Device 3 Photosensitive Member 4 Black Light Writing Position 5 Red Light Writing Position 6 Black Developing Section 7 Red Developing Section

Claims (4)

[Claims] 1. Color image data is converted into bit data for each color.
In an image forming system including a host device that converts the data into image data and transmits the data to the image forming device, and an image forming device that receives the bit data for each color from the host device to generate a printed matter, the bit data for each color -When transmitting the data from the host device, color information of the bit data to be transmitted is added before the bit data for each color, and the color information is stored in the storage means corresponding to each color provided in the image forming apparatus. An image forming system which stores bit data for each color based on the above. 2. A bit data received by the image forming apparatus by detecting a receivable upper state of each storage means based on the remaining storage capacity of the storage means for each color provided in the image device.
The image forming system according to claim 1, wherein the type of data is determined. 3. The data already stored in the storage means based on the amount of data already stored in the storage means provided in the image forming apparatus and the printing speed of the image formation apparatus.
It is characterized in that whether or not the amount of data is insufficient is calculated, and if it is determined that the amount of data is insufficient, the color of the insufficient bit data is designated and a transmission request is made to the host device. The image forming system according to claim 1. 4. The priority is added to each color to be received when the storage means corresponding to at least two colors in the storage means for each color is in a receivable state. Image forming system. [0001]