JPH06225120A - Image forming device - Google Patents

Abstract

PURPOSE:To execute the synthesis mode at a low cost by forming a picture at a prescribed position in an area of an image carrier corresponding to designated transfer paper every time an original picture is received so as to omit a picture memory. CONSTITUTION:Reading of Bk picture data is started by a color scanner when copying is started and optical write and latent image forming are started based on the picture data. Before a latent image tip reaches a development position of a Bk developer 14 so as to develop the tip of a Bk latent image, the rotation of a development sleeve 14-1 is started to execute agent napping thereby developing the Bk latent image by a Bk toner. When the end passes through the development position after the latent image forming, the agent of the sleeve 14-1 is quickly interrupted. The Bk toner image formed on a photosensing drum is transferred to the surface of an intermediate transfer belt 19 rotated at an equal speed to that of the photosensing drum. Toner images of Bk, C, M, Y formed sequentially on the photosensing body drum are positioned sequentially to a belt 19 to form a belt transfer picture in four color overlapping and the picture is transferred onto the transfer paper simultaneously.

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 capable of setting a variable magnification mode and a combining mode, and more particularly to an image forming apparatus capable of executing the combining mode without using an image memory.

[0002]

2. Description of the Related Art Generally, in image composition of a plurality of originals, as disclosed in Japanese Patent Laid-Open No. 3-172073, part or all of the image data of the read originals is temporarily stored in an image memory and then read. It is performed by forming (writing) each image at a predetermined position on the image carrier.

[0003]

The above-mentioned conventional apparatus has a drawback in that it requires an image memory for storing a plurality of image data, resulting in high cost.

An object of the present invention is to provide an image forming apparatus which can omit the image memory and can carry out the combining mode at a low cost.

[0005]

SUMMARY OF THE INVENTION The above-described object is to specify a combination mode for combining a plurality of predetermined document images on one transfer sheet in an image forming apparatus capable of setting a variable magnification mode and a combination mode. By the synthesizing mode designating means and the designation input of the synthesizing mode designating means, every time the manuscript image is read from the first manuscript, the image is formed at a predetermined position in the area on the image carrier corresponding to the designated transfer sheet. And an image forming unit that forms the image.

[0006]

According to the present invention, the image is formed at a predetermined position in the area on the image carrier corresponding to the designated transfer paper every time the original image is read from the first original in the composite mode. , The image memory is omitted.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a color copying apparatus according to an embodiment, and FIG. 2 is an enlarged block diagram of an image forming section thereof.

A color image reading device (hereinafter referred to as a color scanner) 1 displays an image of an original 3 on an illumination lamp 4,
An image is formed on the color sensor 7 via the mirror group 5 (5-1 to 5-3) and the lens 6, and the color image information of the original is displayed, for example, in Blue (hereinafter referred to as B) or Green.
(G, G) and Red (G, R) color-separated lights are read and converted into electrical image signals.

The color sensor 7 is B, G, R in this example.
The color separation means is composed of a photoelectric conversion element such as a CCD, and simultaneously reads three colors. Then, based on the B, G, and R color-separated image signal intensity levels obtained by the color scanner 1, color conversion processing is performed by an image processing unit (not shown), and Black (hereinafter referred to as Bk), Cyan
(Same as C), Magenta (Same as M), Yellow
(Y, Y) color image data is obtained. A color image recording device (hereinafter, referred to as a color printer) 2 described below visualizes the latent images of Bk, C, M, and Y to obtain a final color copy.

The operation system of the color scanner 1 for obtaining the image data of Bk, C, M, and Y is as shown in FIG. 1 in response to a scan start signal which is timed with the operation of the color printer 2. The mirror optical system scans the document in the direction of the left arrow to obtain image data of one color for each scan. By repeating this operation four times in total, sequential four-color image data is obtained. Then, each time, the image is sequentially visualized by the color printer 2, and these are superposed to form a four-color full-color image.

Next, the outline of the color printer 2 will be described.

The writing optical unit 8 converts the color image data from the color scanner 1 into an optical signal, performs optical writing corresponding to the original image, and forms an electrostatic latent image on the photosensitive drum 9. The optical unit 8 includes a laser 8-1.
And its light emission drive control unit (not shown), polygon mirror 8
-2, a rotation motor 8-3 thereof, an f / θ lens 8-4, a reflection mirror 8-5, and the like.

The photoconductor drum 9 rotates counterclockwise as indicated by an arrow, and around the photoconductor drum 9, a photoconductor cleaning unit (including a pre-cleaning static eliminator) 10, a static elimination lamp 11, a charger 12, and a potential sensor 13 are provided. , Bk developing device 1
4, a C developing device 15, an M developing device 16, a Y developing device 17, a development density pattern detector 18, an intermediate transfer belt 19 and the like are arranged.

Each developing device rotates a developing sleeve (14-1, 15-1, 16-1, 17) in which the brush of the developer is brought into contact with the surface of the photosensitive drum 9 to develop the electrostatic latent image. −
1) and a developing paddle (14-2, 15-2, 16-2, 17-) that rotates to pump up and stir the developer.
2) and a toner concentration detection sensor for the developer (14-
3, 15-3, 16-3, 17-3) and the like.

In the standby state, all the four developing devices are in a state where the developer on the developing sleeves is in the state of cutting off (development inoperative) state, but the order of the developing operation (color image forming order) is B.
An example of k, C, M, and Y will be described below (however, the image forming order is not limited to this).

When the copy operation is started, the color scanner 1 starts reading Bk image data from a predetermined timing, and optical writing by a laser beam and latent image formation are started based on the image data (hereinafter referred to as Bk image data). The electrostatic latent image is called a Bk latent image. The same applies to C, M, and Y). In order to enable development from the front end of the Bk latent image, the developing sleeve 14-1 is started to rotate to raise the agent before the front end of the latent image reaches the developing position of the Bk developing device 14. The latent image is developed with Bk toner. After that, the developing operation of the Bk latent image area is continued, but when the trailing edge of the latent image passes the Bk developing position, the agent cutting on the Bk developing sleeve 14-1 is promptly performed to make the developing inoperative state. To do. This is completed at least before the leading edge of the C latent image by the next C image data arrives. It should be noted that the brush cutting is performed by switching the rotation direction of the developing sleeve 14-1 to the opposite direction to that during the developing operation.

Now, the Bk toner image formed on the photosensitive drum 9 is transferred onto the surface of the intermediate transfer belt 19 which is driven at the same speed as the photosensitive drum 9 (hereinafter, from the photosensitive belt 9 to the intermediate transfer belt 19). The toner image transfer is called belt transfer).

The belt transfer is performed by transferring the transfer bias roller 2 when the photosensitive drum 9 and the intermediate transfer belt 19 are in contact with each other.
This is performed by applying a predetermined bias voltage to 0.

On the intermediate transfer belt 19, Bk, C, M and Y toner images sequentially formed on the photosensitive drum 9 are
By sequentially aligning on the same surface, a belt transfer image of four colors is formed, and then batch transfer is performed on a transfer paper. The structure and operation of this intermediate transfer belt unit will be described later.

On the side of the photoconductor drum 9, the Bk process is followed by the C process, but the C image data reading by the color scanner 1 starts at a predetermined timing, and the C latent image is formed by the laser light writing by the image data. To do.

The C developing device 15 starts to rotate the developing sleeve 15-1 after the rear end of the previous Bk latent image has passed the developing position and before the front end of the C latent image reaches. The agent is raised and the C latent image is developed with C toner. After that, C
The development of the latent image area is continued, but when the trailing edge of the latent image passes, the agent cutting on the C developing sleeve 15-1 is performed as in the case of the Bk developing device 14 described above. This is completed before the leading edge of the next M latent image reaches.

The steps of M and Y are the same as the steps of Bk and C, respectively, such as the operations of reading image data, forming a latent image, and developing, and therefore the description thereof will be omitted.

Next, the intermediate transfer belt unit will be described.

The intermediate transfer belt 19 is stretched around a belt transfer bias roller 20, a driving roller 21, and a driven roller group, and is driven and controlled by a driving motor (not shown) as described later.

The belt cleaning unit 22 is composed of a brush roller 22-1, a rubber blade 22-2, a belt contact / separation mechanism 22-3, and the like. After the belt Bk image of the first color is transferred, While the second, third, and fourth colors are being transferred on the belt, the belt cleaning unit 22 is separated from the belt surface by the contact / separation mechanism 22-3.

The paper transfer unit 23 includes a paper transfer bias roller 23-1 and a roller cleaning blade 23-.
2 and a belt contact / separation mechanism 23-3 and the like. The bias roller 23-1 is normally separated from the surface of the intermediate transfer belt 19, but
The four-color superposed images formed on the nine surfaces are pressed by the contact / separation mechanism 23-3 at a timing when the four-color superposed images are collectively transferred to the transfer paper 24, and at this time, a predetermined bias voltage is applied to the bias roller 23-1. Then, the transfer onto the transfer paper 24 is performed.

It should be noted that the transfer paper 24 is transferred onto the surface of the intermediate transfer belt 19 by the paper feed roller 25 and the registration roller 26.
The leading edge of the color-superimposed image is fed at the timing when it reaches the paper transfer position.

The intermediate transfer belt 19 has the first color B
After the belt transfer of the k toner image is completed up to the rear end portion, the intermediate transfer belt 19 is separated from the surface of the photosensitive drum 9, and the forward movement is stopped, and at the same time, the intermediate transfer belt 19 is controlled to return in the opposite direction at a high speed.

At the time of return, the front end position of the Bk image on the surface of the intermediate transfer belt 19 passes the position corresponding to the belt transfer in the opposite direction, and after moving a preset distance, the intermediate transfer belt 19 is stopped. , Put it in a standby state.

Next, when the front end portion of the C toner image on the photosensitive drum 9 side reaches a predetermined position before the belt transfer position, the intermediate transfer belt 19 is restarted in the forward direction. Further, the intermediate transfer belt 19 is brought into contact with the surface of the photosensitive drum 9 again. Also in this case, the C image is transferred under the condition that it is accurately overlapped with the Bk image on the surface of the intermediate transfer belt 19.

Thereafter, by the same operation, the process proceeds to the M, Y image process to obtain a belt transfer image of four-color overlapping. Subsequent to the belt transfer process of the Y toner image of the fourth color, the intermediate transfer belt 19 is returned in order to align the front end of the transfer paper 24 with the front end of the belt transfer image, and then moves forward at a speed synchronized with the speed of the transfer paper 24. Then, the four-color superposed toner images on the surface of the intermediate transfer belt 19 are collectively transferred onto the transfer paper 24. It should be noted that the reason why the intermediate transfer belt 19 returns without rotating once in the forward direction after the belt transfer step of the Y toner image is that when the belt is used as the transfer member, the belt is shifted to the left and right with respect to the rotation direction. This is because one rotation causes a positional shift.

The transfer paper 24 to which the four-color superposed toner images are collectively transferred from the surface of the intermediate transfer belt 19 is conveyed to the fixing device 28 by the paper conveying unit 27, and the fixing roller 28-1 controlled to a predetermined temperature. With the pressure roller 28-2,
The toner image is fused and fixed and carried out to the copy tray 29 to obtain a full color copy.

The photosensitive drum 9 after the belt transfer is
Photoreceptor cleaning unit 10 (pre-cleaning static eliminator 10-1, brush roller 10-2, rubber blade 10
-3) The surface is cleaned and the static elimination lamp 1
With 1, the charge is uniformly removed.

After the toner image is transferred onto the transfer paper 24, the surface of the intermediate transfer belt 19 is cleaned by pressing the belt cleaning unit 22 again by the contact / separation mechanism 22-3.

At the time of repeat copying, the operation of the color scanner 1 and the image formation on the photosensitive drum 9 are continued from the Y (fourth color) image process of the first sheet, and then the Bk (first color of the second sheet) at a predetermined timing. ) Proceed to the image process.

Further, in the intermediate transfer belt 19, after the batch transfer process of the first four-color superimposed image onto the transfer paper 24, the surface of the intermediate transfer belt 19 is cleaned by the belt cleaning unit 22, and the second sheet is transferred to the intermediate transfer belt 19. The Bk toner image is transferred on the belt. After that, the same operation as the first sheet is performed.

The transfer paper cassettes 30, 31, 32,
A transfer paper 33 of various sizes is stored, and is fed and conveyed toward the registration roller 26 at a timing from a transfer paper cassette of a size paper designated by an operation panel (not shown). Reference numeral 34 is a manual paper feed tray for OHP paper or thick paper.

Up to this point, the description has been given of the copy mode for obtaining four full colors, but in the case of the three-color copy mode and the two-color copy mode, the designated color and the number of times are
The same operation as above is performed.

In the single-color copy mode, until the predetermined number of sheets are completed, only the developing device of that color is in a developing operation (agent standing) state, and the intermediate transfer belt 19 has the photosensitive drum 9 surface. Drives at a constant speed in the forward direction while touching
Further, the belt cleaning unit 22 also performs the copy operation while being in contact with the intermediate transfer belt 19.

Next, the operation when combining a plurality of originals will be described.

As an example, four originals (first
The operation of forming an image by combining the original 101, the second original 102, the third original 103, and the fourth original 104) into one sheet will be described.

The image formation of the first original 101 is the same as the above until the transfer of the Y toner to the intermediate transfer belt 19.
After this, the intermediate transfer belt 19 separates the intermediate transfer belt 19 from the surface of the photosensitive drum 9 after the belt transfer of the Y toner image of the fourth color is completed up to the rear end, and at the same time the forward movement is stopped. It is controlled to return in the opposite direction at high speed (this is similar to the return for the first, second, and third colors). The image on the intermediate transfer belt 19 here is as shown in FIG.

Next, an image of the second original 102 is created.
The position of the image to be created is instructed in advance on the size of the transfer paper 24 and the number of originals (the size of the original is instructed in advance, or it is detected by the reading device and is known). Therefore, it is calculated what percentage of the original should be magnified to form four original images on the transfer paper 24 to be used, and where the starting point of image formation should be.

The image formation of the second original 102 is performed except for the position of the intermediate transfer belt 19 and the starting point of the image formation.
It is performed in the same manner as the step 01. The image on the intermediate transfer belt 19 here is as shown in FIG.

Thereafter, similarly, an image is formed while shifting the image position on the intermediate transfer belt 19 for each original. Then, after transferring the Y image of the fourth original 104 to the intermediate transfer belt 19, the intermediate transfer belt 19 is returned so as to align the front end of the transfer paper 24 with the front end of the belt transfer image, and then synchronized with the speed of the transfer paper 24. The four-color superposed toner images on the surface of the intermediate transfer belt 19 are collectively transferred to the transfer paper 24 at a forward speed. In this way, the four-color superimposed toner image is transferred onto the transfer paper 24.
After being transferred to the transfer paper 24, the transfer paper 24
Is conveyed to a fixing device 28 by a paper conveying unit 27, and a toner image is melted and fixed by a fixing roller 28-1 and a pressure roller 28-2, which are controlled to a predetermined temperature, and then the toner image is conveyed to a copy tray 29 for full color copying. To get The image here is shown in FIG.

[0047]

According to the first aspect of the invention, each time an original image is read in order from the first original in the composite mode, a predetermined area within the area on the image carrier corresponding to the designated transfer sheet is read. By forming the image at the position, the image memory can be omitted.

According to the second aspect of the present invention, instead of directly transferring the composite image from the photosensitive drum to the transfer paper, the composite image is formed at a predetermined position of the intermediate transfer belt and transferred to the transfer paper. Therefore, it is not necessary to complicate the image forming process control for the photosensitive drum in the combining mode.

According to the third aspect of the invention, it is not necessary to instruct the size of the image to be created from the number of originals and the size of the transfer paper in the composition mode, so that the operability can be greatly improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a color copying apparatus according to an embodiment of the present invention.

FIG. 2 is an enlarged configuration diagram of an image forming unit of the color copying apparatus according to the embodiment of the present invention.

FIG. 3 is a perspective view showing a plurality of originals to be combined.

FIG. 4 is a schematic diagram showing each image forming process of the intermediate transfer belt when the combination mode is executed.

5 is a schematic diagram showing a composite image of the four originals shown in FIG.

[Explanation of symbols]

 9 Photoconductor drum 19 Intermediate transfer belt 24 Transfer paper

Claims (3)

[Claims] 1. An image forming apparatus capable of setting a scaling mode for scaling an image and a composite mode for combining a plurality of predetermined document images on one transfer sheet, wherein the composite mode is designated. By the synthesizing mode designating means and the designation input of the synthesizing mode designating means, every time the manuscript image is read from the first manuscript, the image is formed at a predetermined position in the area on the image carrier corresponding to the designated transfer sheet. An image forming apparatus comprising: an image forming unit that forms the image. 2. The image forming apparatus according to claim 1, wherein the image carrier for directly transferring the plurality of composite images to the transfer paper is an intermediate transfer belt. 3. The image forming apparatus according to claim 1, wherein the magnification of one original image is determined by the number of originals and the size of transfer paper when the composite mode is executed.