JPH06316118A - Image forming apparatus - Google Patents

Abstract

PURPOSE:To provide an image forming apparatus enhanced in printing efficiency capable of changing an image forming speed corresponding to the data quantity of a page. CONSTITUTION:In an image forming apparatus equipped with a band data storage means 23 storing the data of a plurality of bands formed by dividing the image data corresponding to one page and a page data storage means 24 storing the data corresponding to one page constituted of the data of a plurality of the bands transmitted from the band data storage means, image forming speed setting means 25, 26, 28 automatically setting the image forming speed of the page containing the data of the bands on the basis of the max. data quantity of the bands stored in the band data storage means are provided. When the max. data quantity of the bands is much and a time is taken in the development from band data to page data, an image forming speed is set so as to become slow and, when the max. data quantity of the bands is little and a time is not taken in the development to page data, the image forming speed is set so as to become fast.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for printing on paper based on data transferred from a computer or the like, and more particularly to printing by setting the printing speed according to the data amount of each page. It is a streamlined version of.

2. Description of the Related Art In recent years, with the widespread use of personal computers and the like, the fields of use of image forming apparatuses connected to them have expanded, and image forming apparatuses having various functions have been used according to the respective fields. There is.

A page printer, which is one of such image forming apparatuses, stores page data for storing image data for one page in order to print in page units.
This page data memory has 1
The printing operation is started each time image data for one page is transferred, and printing is performed page by page.

In this image forming apparatus, before the data transferred from the host computer or the like is sent to the page data memory, the data amount for one page is divided into a plurality of pieces and temporarily stored in the buffer memory. -The difference in data transfer speed is adjusted by transferring data from memory to page data memory.

As shown in FIG. 9, a conventional image forming apparatus of this type includes an image processing section 2 for converting image data transferred from a host computer 1 through a cable 5 into page data for each page, and a paper. It is composed of an image forming unit 4 that executes printing on the upper side and an image forming control unit 3 that controls the image forming unit 4.

The image processor 2 is a host computer 1.
An input unit 21 for receiving commands and image data sent from a device, a command data memory 22 for storing the received commands and data, and a display for storing the data amount for one page by dividing it into a plurality of parts. List memory 29,
A page data memory 24 that stores page data for one page, an interface unit 27 that outputs data to the image formation control unit 3 through the cable 6, and a central processing unit (CPU) that controls image data processing according to a received command. 25 and.

Further, the image forming control section 3 includes an image forming section 4
A speed data memory 32 for storing cycle data relating to the image forming speed and a CPU 31 for controlling the operation of the image forming section 4 at the cycle read from the speed data memory 32.

In the case of a laser printer, the image forming section 4 includes a laser unit 41 for generating a laser beam 42 according to page data and a mirror 43 for reflecting the laser beam.
And a photoreceptor 44 on which a latent image is formed by the laser light 42,
A developing device 45 for converting a latent image into a visible image, a paper cassette 46 for feeding the paper 47, a transfer device 48 for transferring the visible image on the paper, and a fixing device 49 for fixing the visible image on the paper. ing.

In this image forming apparatus, when commands and image data are received from the host computer 1 via the cable 5, the commands and data are accepted by the input section 21, and then the command data memory 22 is received.
To store. The CPU 25 has a command data memory 22.
Interprets each command and data stored in, and displays the image data stored therein in a display list for each band (one division when the image area for one page is divided into a plurality of bands, Change the image data for one band to "display list")
Store in list memory 29.

Next, the CPU 25 transfers several bands of the display list stored in the display list memory 29 to the page data memory 24 and develops the page data for one page.

At the same time, the CPU 25 issues a command to the image forming control section 3 via the cable 6 to operate the image forming section 4. CP of the image formation control unit 3 which has received the command
The U31 extracts a cycle from the cycle data (there is only one) stored in the speed data memory 32, and operates the operation of the image forming unit 4 via the cable 7 using the extracted cycle.

When the expansion into page data is completed, the CPU 25 of the image processing section 2 outputs a print signal to the image forming control section 3 via the cable 6 to check whether the image forming section 4 is ready for printing. Check. When printing is possible, the CPU 31 of the image forming control unit 3 turns on the motors of the photoconductor 44 and the laser unit 41 of the image forming unit 4, prepares for laser emission, etc. Processing unit 2
The vertical sync signal is output to.

The CPU 25 of the image processing unit 2 checks whether or not the vertical synchronizing signal for prompting the start of printing is output. When the vertical synchronizing signal is turned on, the page data is immediately taken out from the page data memory 24 and the image forming control is performed. Send to Part 3.

At the same time, the CPU 25 displays in the empty page data memory 24 a display list for several bands constituting the next page data.
Expand from memory 29.

On the other hand, the image forming control unit 3 includes an image forming unit 4
Is controlled as follows. C of the image formation controller 3
The PU 31 uses the laser unit 41 to convert the input page data.
Then, the laser unit 41 generates a laser beam 42 according to the transferred data. The laser light 42 is applied to the photoconductor 44 to expose the photoconductor 44 to form a latent image.

Then, in the developing device 45, a developing bias is applied to develop the latent image, and the latent image is visualized.
A visible image is generated on 44. Then, the paper cassette 46
The paper 47 is fed from the paper, and the transfer bias is applied to the transfer device 48 at the timing when the image is placed on the paper to transfer the visible image to the paper 47.

Then, a visible image is fixed on the paper 47 in the process of passing the paper through the fixing device 49, it is checked whether the paper 47 is discharged, each motor is turned off, and the printing is completed.

[0017]

In this conventional image forming apparatus, since the image forming speed is determined by one kind of cycle data stored in the speed data memory 32, it is related to the data amount of the page to be printed. Not always a constant speed.

When the image forming speed is uniformly increased, when a complicated page having a large amount of data is printed, the expansion from the display list to the page data cannot catch up with the image forming speed, which causes an error. . On the other hand, if the image forming speed is set to be slow in accordance with the printing of complicated pages, a lot of time is consumed even when printing a page with a small amount of data. Therefore, the printing efficiency of the conventional image forming apparatus cannot be said to be good.

The present invention solves these conventional problems, and an object of the present invention is to provide an image forming apparatus with high printing efficiency, which can change the image forming speed according to the amount of data on a page.

[0020]

Therefore, in the present invention, 1
Band information storage means for storing information of each band when the image area for pages is divided into a plurality of bands, and information for one page composed of information of the plurality of bands transferred from the band information storage means In an image forming apparatus having a page data storage unit for storing, an image forming speed for automatically setting an image forming speed of a page including information of the band based on the maximum information amount of the band stored in the band information storage unit. A setting means is provided.

[0021]

Therefore, when the maximum information amount of the band is large and therefore it takes a long time to develop the band information into the page data, the image forming speed is set to be slow, and the maximum information amount of the band is small, so that the band information is small. When it takes no time to convert the page data to page data, the image forming speed can be set high and efficient printing can be performed.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, an image forming apparatus according to an embodiment of the present invention includes an image processing unit 2 having a display block memory 23 for temporarily storing data to be expanded into page data and a page. A maximum data memory 26 for storing the maximum amount of data contained in a band expanded into minute page data and a speed determination data memory 28 for storing a plurality of cycle data for determining the image forming speed are provided. . In addition, the speed data memory 32 of the image forming controller 3
Stores the same plurality of cycle data stored in the speed determination data memory 26. Other configurations are
It is no different from the conventional device (Fig. 9).

The CPU 25 of the image processing unit 2 creates a display block from the data input from the host computer 1 and stored in the command data memory 22, and stores it in the display block memory 23. .

As shown in FIG. 3, this display block is composed of data representing the information amount of each band expanded into page data for one page and display information of the band. , Fig. 2
As shown in, each band is composed of information indicating where in the band the image or text is located and the image data of the image or text linked to the information.

The information amount of the band in the display block is the sum of the information amounts of the image and the text itself. However, even if the information amounts of the image and the text are the same, there is a difference in the expansion time to the page data. If the error occurs, the information amount of the image is multiplied by several times so as to be proportional to the development time, and the sum is added.

Further, the maximum data memory 26 stores a value representing the largest amount of band information in the display block for one page stored in the display block memory 23.

Hereinafter, the printing operation in the image forming apparatus of the embodiment will be described with reference to the flow charts of FIGS. 5 to 8, assuming that one page is divided into 5 bands and the speed of the image forming unit 4 is switched to three stages. To do.

Step 1: Input data (command, image, etc.) from the host computer 1 is transferred to the cable 5.
It is taken into the input unit 21 of the image processing unit 2 via the step S2 and stored in the command data memory 22 in step 2; Step 3; CPU 25 has command data memory 22
A display block is created from the data captured in the display block memory 23 and stored in the display block memory 23, and the CPU 25 selects one of the display blocks stored in the display block memory 23. The largest amount of band information is stored in the maximum data memory 26.

Step 5; Next, the CPU 25 determines how much the image forming speed should be set when the maximum amount of band information is reached before the display information can be expanded into page data in time. Therefore, when the image forming speed is set at the fastest cycle 1 of the three kinds of cycles (shown in FIG. 4) held in the speed determination data memory 28, the display information is expanded into page data. The maximum amount of data in time is compared with the value stored in the maximum data memory 26 to determine which is smaller. Step 6; If the value stored in the maximum data memory 26 is smaller, the page Since it means that the development into data is in time, the CPU 31 of the image forming control unit 3
Then, a command is sent to control the image forming speed in cycle 1. Step 7: Upon receipt of the command, the CPU 31 takes out cycle 1 from the cycle data (same as in FIG. 4) stored in the speed data memory 32, and uses this cycle 1 to make the image forming unit 4
Control the behavior of.

In step 5, the maximum data
If the value stored in the memory 26 is larger, it means that the image forming speed of the cycle 1 is too late to develop the page data, so the process proceeds to step 8; step 8; The maximum data amount stored in the decision data memory 28 and the value stored in the maximum data memory 26 when the image forming speed is set at the second fastest cycle 2 and the expansion from display information to page data is in time. Step 9: If the value stored in the maximum data memory 26 is smaller, the CPU 31 of the image forming control unit 3 controls the image forming speed in cycle 2. To send the command. Step 10: The CPU 31, which has received the command, sets the speed data
The cycle 2 stored in the memory 32 is taken out, and this cycle 2
Is used to control the operation of the image forming unit 4.

Step 11; Further, when the value stored in the maximum data memory 26 is larger in Step 8, the CPU 31 of the image forming controller 3 controls the image forming speed in the cycle 3. Send an order. Step 12: The CPU 31 which has received the command
The cycle 3 stored in the memory 32 is taken out, and this cycle 3
Is used to control the operation of the image forming unit 4.

Step 13; Subsequently, the CPU 25 expands the image data from the display information in the display block memory 23 and stores the page data to be actually printed in the page data memory 24.

Step 14: Send a print signal from the image processing unit 2 to the image forming control unit 3, Step 15: Check whether the image forming unit 4 is in a printable state, Step 16: If printing is possible, The CPU 31 of the image forming control unit 3 turns on the motors of the photoconductor 44, the laser unit 41 and the like of the image forming unit 4 to prepare for laser emission and the like.

Step 17: CPU 25 of image processing unit 2
Checks whether or not the vertical synchronizing signal for starting printing is output to the image processing unit 2. Step 18; immediately after the vertical synchronizing signal is turned on,
The page data is fetched from the page data memory 24 and sent to the image forming controller 3.

The CPU 31 of the image forming control section 3 controls the image forming section 4 as follows. Step 19: A laser beam 42 having a laser power corresponding to the transferred data is emitted from the laser unit 41 to irradiate the photoconductor 44 for exposure, and Step 20: the latent image is visualized by the developing device 45, Photoconductor 44
Generate a visible image on top. Step 21: Paper is formed at the timing when the visible image is placed on the paper.
47 is fed from the cassette 46 and the visible image is transferred onto the paper, step 22; then the fixing device 49 fixes the image on the paper, step 23; it is checked whether the paper is ejected, step 24 When the paper has been discharged, the motors are turned off to finish the printing.

As described above, in the image forming apparatus of the embodiment,
When the fastest image formation speed is set, it is judged whether the expansion from display information to page data is in time, and if it is in time, image formation is performed at that speed, and if it is not in time, the next speed is set. If set,
It is determined whether the display information can be expanded into page data in time.

Therefore, each page is printed at the image forming speed at which the development of the display information into the page data is in time, and at the highest image forming speed.

Although the laser printer has been described in the embodiment, the present invention can be applied to other printers.

[0039]

As is apparent from the above description of the embodiments, in the image forming apparatus of the present invention, the image forming speed is within a range in which a printing error does not occur depending on the information amount of the page to be printed. Since it can be automatically changed to a higher speed, efficient printing is possible and error occurrence can be suppressed.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of an image forming apparatus of the present invention,

FIG. 2 is a data configuration diagram of display information used in the image forming apparatus of the embodiment,

FIG. 3 shows a display used in the image forming apparatus of the embodiment.
Block data structure diagram,

FIG. 4 is a waveform chart showing a plurality of cycles that determine an image forming speed of the image forming apparatus according to the embodiment.

FIG. 5 is a flowchart (No. 1) showing an operation procedure of the image forming apparatus according to the embodiment.

FIG. 6 is a flowchart (part 2) showing the operation procedure of the image forming apparatus according to the embodiment.

FIG. 7 is a flowchart (No. 3) showing an operation procedure of the image forming apparatus according to the embodiment.

FIG. 8 is a flowchart (part 4) showing the operation procedure of the image forming apparatus according to the embodiment;

FIG. 9 is a block diagram showing a configuration of a conventional image forming apparatus.

[Explanation of symbols]

 1 Host computer 2 Image processing unit 21 Input unit 22 Command data memory 23 Display block memory 24 Page data memory 25, 31 CPU 26 Maximum data memory 27 Interface unit 28 Speed determination data memory 29 Display list・ Memory 3 Image forming control unit 32 Speed data memory 4 Image forming unit 4 Image forming unit 41 Laser unit 42 Laser light 43 Mirror 44 Photoreceptor 45 Developing device 46 Paper cassette 47 Paper 48 Transfer device 49 Fixing device 5, 6, 7 cable

Claims (1)

[Claims] 1. A band information storage unit for storing information of each band when an image area for one page is divided into a plurality of bands, and a plurality of band information transferred from the band information storage unit. An image forming apparatus including a page data storage unit that stores information for one page according to the maximum information amount of the band stored in the band information storage unit. An image forming apparatus comprising an image forming speed setting means for automatically setting a speed.