JPH04337752A - Image recording process controlling method and its device for image recorder - Google Patents

Abstract

PURPOSE:To effectively prevent the deterioration of image quality caused by suspending toner along with making a transfer body large in size and shortening the time of replacing a developing means, and to attain the high speed of recording the image by the mode of holding two recording sheets. CONSTITUTION:The half-rotation cycle of the transfer body 5 is used as the reference cycle of recording the image, and a toner image provided with each color component is transferred to the recording sheets 4 which are held one on the other by performing the half-rotation cycle twice with reference to the transfer body, thus, the transfer operation is stopped at the following half- rotation cycle, and the developing means 3 is replaced by making good use of the stop cycle.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] This invention relates to an image recording process control method and apparatus applied to an image recording apparatus that transfers toner images of each color component on an image carrier multiple times to a recording sheet wound around a transfer member and held therein. In particular, the present invention relates to an image recording process control method and an improvement of an apparatus for controlling the image recording process that is effective in executing a double-hook mode in which two recording sheets are simultaneously held on a transfer body.

0002

[Prior Art] Conventionally, this type of image recording apparatus rotates a photosensitive drum as an image carrier and a transfer drum synchronously, and multiplexes each color toner image on the photosensitive drum onto a recording sheet held on the transfer drum. Some toner images are fixed in a fixing device after being transferred. In this type of image recording apparatus, the entire sequence is normally controlled based on the transfer drum (see Japanese Patent Laid-Open No. 62-279361). That is, the transfer drum is usually provided with a metal tie bar extending in the direction of the drum axis as part of the drum frame, and the transfer operation to the recording sheet cannot be performed at a location corresponding to the tie bar position. , the tie bar position serves as the reference for the entire sequence, including exposure scanning, feeding of the recording sheet to the transfer drum, and transfer positioning between the recording sheet held on the transfer drum and the toner image on the photosensitive drum (inside the transfer drum). The on/off operation of the incorporated transfer corotron, the peeling operation of the recording sheet, etc. are controlled.

By the way, in this type of image recording apparatus, based on the request to perform image recording at high speed, two sheet holding surfaces A and B on the surface of the transfer drum have, for example, A4
The two recording sheets of the plate were held together by suction, and the processes of exposure, development, and transfer of each color component were performed on the two recording sheets in the order of sheet holding surfaces A and B of the transfer drum. (See JP-A-2-6984, Color Laser Copier 200 manufactured by Canon Co., Ltd.).

0004

[Problems to be Solved by the Invention] In this type, the exposure of each color component,
Each process of development and transfer is performed, and after each process of exposure, development, and transfer of a predetermined color component to the sheet holding surface B is completed, the developing device for developing the next color component is replaced. is necessary. At this time, if the rotational speed of the transfer drum is set to be faster in order to increase the image recording speed, there is a technical problem in that it becomes difficult to secure a cycle time for replacing the developing device during one rotation cycle of the transfer drum. An issue was discovered.

Means for solving such technical problems include, for example, increasing the diameter of the transfer drum to ensure a replacement cycle time for the developing device, or
It is possible to shorten the replacement cycle time of the developing device, but the former type does not meet the requirement of making the device itself more compact, and the latter type does not meet the requirement to make the device itself compact. A new technical problem arises in that developer spillage is likely to occur during replacement, and image quality is likely to deteriorate due to contamination caused by floating toner.

On the other hand, as shown in Japanese Unexamined Patent Publication No. 63-44670, if the developer replacement cycle time cannot be secured during one rotation cycle of the transfer drum, a dummy cycle for one rotation of the transfer drum is used. It is conceivable that the developing device be replaced during this dummy cycle, but in this type, two recording sheets are hung on the transfer drum to increase the image recording speed. This results in a situation where being there becomes completely meaningless.

The present invention has been made to solve the above-mentioned technical problems, and effectively prevents the deterioration of image quality due to floating toner caused by increasing the size of the transfer body and shortening the time required to replace the developing means. However, it is an object of the present invention to provide an image recording process control method for an image recording apparatus and an apparatus therefor, which are designed to further increase the image recording speed in the double recording sheet mode.

[0008]

[Means for Solving the Problems] That is, as shown in FIG. 1, the image recording process control method for an image recording apparatus according to the present invention includes an image carrier 1 and static images of each color component on the image carrier 1. A latent image forming means 2 that sequentially forms an electrostatic latent image, and a plurality of developing means 3 (for example, 3a, 3b, 3c,
3d), and has sheet holding surfaces A and B in semicircular units on which two recording sheets 4 are held, and is rotationally driven in synchronization with the image carrier 1 and held on the sheet holding surfaces A and B. A transfer member 5 that transfers the toner images of each color on the image carrier 1 multiple times onto a recording sheet 4 is inserted into the recording sheet 4, which is peeled off from the transfer member 5 after the transfer process of the final color is completed, and the recording sheet 4 is transferred onto the recording sheet 4. It is assumed that the image recording apparatus is equipped with a fixing means 6 for fixing an unfixed toner image of There is a mode selection step for selecting whether the two-fold mode is selected, and when the single-fold mode is selected in this mode selection step, one sheet holding surface A of the transfer body 5 or from one sheet holding surface A to the other is selected. The recording sheet 4 is held across the sheet holding surface B of the transfer member 5 during the transfer process of a predetermined color toner image formed on the image carrier 1 during one rotation cycle of the transfer member 5. In the standard image recording process in which the exchange steps 3c and 3d) are performed and in the mode selection process described above, when the two-sheet mode is selected, two recording sheets 4 are placed on each sheet holding surface A, B of the transfer body 5. After the process of transferring a predetermined color toner image formed on the image carrier 1 is repeated twice every half-rotation cycle of the transfer member 5, during the next half-rotation cycle of the transfer member 5, Developing means 3 (3a,
3b, 3c, 3d) is performed, and thereafter, the predetermined color toner formed on the image carrier 1 is removed until the replacement step of the developing means 3 (3a, 3b, 3c, 3d) becomes unnecessary. After the image transfer process is repeated twice every half-rotation cycle of the transfer body 5, only the replacement process of the developing means 3 (3a, 3b, 3c, 3d) is performed during the next half-rotation cycle of the transfer body 5. A special image recording process is performed.

[0009] An apparatus invention embodying such a method is as follows:
As shown in FIG. 1, an image carrier 1, a latent image forming means 2, a plurality of developing means 3 (for example, 3a, 3b, 3c, 3d), and a half-circumferential sheet holding unit in which two recording sheets 4 are held. Assuming that the image recording apparatus is equipped with a transfer body 5 having surfaces A and B and a fixing means 6, the transfer body 5 can hold only one recording sheet 4 in a one-sheet mode, or two recording sheets 4 can be held on the transfer body 5. Mode selection means 7 for selecting which two-hook mode is to be maintained
When the one-sheet mode is selected by the mode selection means 7, the recording sheet 4 is straddled from one sheet holding surface A of the transfer body 5 or from one sheet holding surface A to the other sheet holding surface B. a sheet supplying means 8 for holding two recording sheets 4 on each sheet holding surface A, B of the transfer body 5 when the two-hook mode is selected by the mode selection means 7; The transfer body rotation position detection means 9 detects the half-rotation cycle of the transfer body 5 based on information from the transfer body rotation position detection means 9 when the mode selection means 7 selects the transfer body rotation position detection means 9. The standard image recording transfer control means 10 transfers a predetermined color toner image formed on the image carrier 1 to the recording sheet 4 every rotation cycle, and the mode selection means 7 selects the one-copy mode. When the developing means 3 (3a, 3b, 3c, 3
d) is used to replace the standard image recording development control means 11, and when the two-fold mode is selected by the mode selection means 7, the half of the transfer body 5 is changed based on the information from the transfer body rotation position detection means 9. After the predetermined color toner image formed on the image carrier 1 is transferred to the two recording sheets 4 held on each sheet holding surface A and B in each rotation cycle, the next half rotation of the transfer member 5 is performed. a transfer control means 12 for special image recording, which pauses the transfer operation of the transfer body 5 during the cycle, and thereafter continuously repeats two transfer operations and one transfer pause operation every half-rotation cycle of the transfer body 5; When the two-fold mode is selected by the mode selection means 7, the developing means 3 ( 3a, 3b, 3c, 3
d), and a sheet peeling means 14 for peeling off the recording sheet 4 on the transfer body 5 after the transfer operation of the transfer body 5 of the final color is completed. That is.

In such a technical means, the image carrier 1 may be a photoreceptor or a dielectric material as long as it can form a latent image and also bear a toner image that visualizes the latent image. It can be selected as appropriate, and its structure can be either drum-shaped or belt-shaped.

As for the latent image forming means 2, as long as it can form a latent image corresponding to each color component depending on the type of image carrier 1, it may form a latent image using a light beam, an ion beam, etc. As for the latent image to be formed, the latent image may be formed by reading the document image and based on the read image, or it may be formed based on the image signal prepared in advance. It can be selected as appropriate, such as forming a latent image.

Furthermore, the developing means 3 also has an image recording mode (for example, 4-color mode, 3-color mode, etc.).
It is sufficient to prepare a type that can reproduce colors according to the situation, and regarding the replacement method of the developing means 3, there is a rotary exchange type (a type in which each developing means 3 is rotatably arranged and rotationally arranged as appropriate), a parallel selection type (an image bearing type). (types in which they are arranged in parallel around the body 1 and selected as appropriate) may be selected as appropriate.

Furthermore, regarding the structure of the transfer body 5, if it is capable of executing at least a double-hanging mode in which two recording sheets 4 are held at the same time, it is possible to hold the recording sheets 4 only by electrostatic adsorption force. There may be one, or one held by a gripper and electrostatic adsorption force may be selected as appropriate. In this case, the sheet holding surface A of the transfer body 5,
As for how to set B, sections may be set for each half-rotation cycle based on a predetermined line. Regarding the size of the transfer body 5, during one rotation cycle of the transfer body 5, at least the maximum size recording sheet 4
It is necessary to make a selection so as to ensure a replacement cycle time for the developing means 3 when the developing means 3 is maintained.

Regarding the mode selection means 7,
When performing the same color printing or copying on a plurality of recording sheets, it may be such that the two-copy mode and the single-copy mode are automatically selected,
Further, the design can be changed as appropriate, such as by making it possible to arbitrarily select one of the modes using a switch or the like.

[0015] Regarding the sheet feeding means 8,
The design may be changed as appropriate as long as the recording sheet 4 is held on the transfer body 5 depending on whether the recording sheet 4 is held in one-fold mode or two-fold mode, but from the viewpoint of increasing versatility, recording sheets 4 of multiple sizes can be used. It is preferable to design the system so that it can be selected.

Further, the transfer body rotation position detecting means 9 may be a device coaxial with the transfer body 5, for example, as long as it can detect at least a half-rotation cycle of the transfer body 5 and distinguish between the sheet holding surfaces A and B. A fan-shaped plate with a predetermined angle that rotates is provided, and the edge portion of this fan-shaped plate (rising,
The falling edge portion) may be detected by an optical sensor, or a part of the plate that rotates coaxially with the transfer body 5 may be provided with slits (for example, the slit position and the number of slits) for distinguishing sheet holding surfaces A and B. The design may be changed as appropriate, such as by providing a slit (different, etc.) and detecting this slit optically.

Furthermore, the standard image recording transfer control means 1
0 and the transfer control means 12 for special image recording, each control function may be realized using a microcomputer, etc., but from the viewpoint of minimizing the destruction of transferred toner images during multiple transfer, For example, processing to avoid the situation where the toner image once transferred to the recording sheet 4 side is transferred again to the image carrier 1 side during multiple transfer, for example, charging the recording sheet 4 during the transfer operation of the transfer body 5. It is preferable to perform a process such as increasing the amount of charge in sequence according to the number of overlapping color toner images. In addition, the special image recording transfer control means 12 applies charges for toner image retention to the recording sheet to such an extent that the toner image transferred to the recording sheet 4 side does not transfer to the image carrier 1 side again even during the transfer pause operation. 4
It is preferable to give it to

Furthermore, the standard image recording development control means 11 and the special image recording development control means 13 may also be configured to implement their respective control functions using a microcomputer or the like.

Further, the sheet peeling means 14 may be modified in design as long as it operates in accordance with the peeling timing of the recording sheet 4 and peels off the recording sheet 4 held on the transfer body 5. A peeling finger, a ditack corotron, a sheet extrusion roll for assisting peeling, etc. can be appropriately combined as long as good peeling performance can be maintained. In particular, in the case of the two-hook mode, the peeling methods for each recording sheet 4 on the sheet holding surfaces A and B may be the same or may be designed to be different.

[0020]

[Operation] According to the above-mentioned technical means, when the one-sheet mode is selected by the mode selection means 7, the sheet supply means 8 is fed from the sheet holding surface A of the transfer body 5 or from one sheet holding surface A. The recording sheet 5 is held astride the other sheet holding surface B.

At this time, the standard image recording transfer control means 1
0 transfers a predetermined color toner image formed on the image bearing member 1 to the recording sheet 4 every rotation cycle of the transfer member 5 based on information from the transfer member rotational position detection means 9, and performs standard image recording. The developing control means 12 sequentially replaces the developing means 3 (3a, 3b, 3c, 3d) during one rotation cycle of the transfer body 5 based on information from the transfer body rotational position detection means 9.

Further, when the mode selection means 7 selects the two-sheet mode, the sheet supply means 8 moves the transfer body 5
Two recording sheets 4 are held on each of the sheet holding surfaces A and B.

At this time, the special image recording transfer control means 1
2 holds a predetermined color toner image formed on the image carrier 1 on each sheet holding surface A, B every half rotation cycle of the transfer member 5 based on information from the transfer member rotational position detection means 9. After transferring to the two recording sheets 4, the next transfer sheet 5 is transferred.
The transfer operation of the transfer body 5 is stopped during the half-rotation cycle of
Thereafter, two transfer operations and one transfer pause operation are continuously repeated every half-rotation cycle of the transfer body 5.

On the other hand, the special image recording developing control means 13 controls the developing means 3 (3a, 3a, 3b, 3c, 3d) in sequence.

In either mode, the sheet peeling means 14 peels off the recording sheet 4 on the transfer body 5 after the transfer operation of the final color on the transfer body 5 is completed, and transfers the recording sheet 4 to the fixing means 6 side. transport.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on embodiments shown in the accompanying drawings. FIG. 2 shows an embodiment of a color copying machine to which the present invention is applied. In the figure, reference numeral 20
21 is a photosensitive drum, 21 is a charging corotron that charges the surface of the photosensitive drum 20 in advance, 22 is an exposure scanning system that writes an electrostatic latent image on the photosensitive drum 20 charged by the charging corotron 21, 23 is black (B), a rotary developing unit in which four developing units 23B, 23C, 23M, and 23Y containing cyan (C), magenta (M), and yellow (Y) toner images are rotatably disposed and can be switched and selected as appropriate; 2
4 is a transfer pre-processing corotron that removes the potential on the photosensitive drum 20; 25 is a cleaner that removes residual toner on the photosensitive drum 20; and 26 is an erase lamp that removes the residual charge on the photosensitive drum 20.

In this embodiment, the exposure scanning system 22 includes:
An exposure lamp 223 that irradiates a light beam onto a document 222 set on a platen 221;
a carriage 224 that moves the image across the document 222 area;
, a reflection mirror 225 that guides the beam from the surface of the original 222 by the exposure lamp 223 along a predetermined path, and
A color image sensor 226 converts the beam from the 22nd surface into a digital signal for each color component, an imaging lens 227 focuses the beam from the 222nd surface of the document onto the color image sensor 226, and the image sensor 226 captures the image. The laser scanning unit 228 irradiates the photosensitive drum 20 with a laser beam along the main scanning direction based on the image signal of each color component. The laser scanning unit 228 includes, for example, a semiconductor laser 228a, and a polygon mirror 228 that distributes and deflects the beam from the semiconductor laser 228a over the main scanning direction of the photosensitive drum 20.
b. The beam from the semiconductor laser 228a is transferred to the photosensitive drum 2.
Imaging lens 2 that forms an image along the main scanning direction line 0
28c and a reflecting mirror 228d that regulates the beam path.

Further, reference numeral 31 indicates a recording sheet 30 (
This is a transfer drum on which an OHP sheet (or plain paper) is wound and held, and the toner images of each color component on the photosensitive drum 20 are sequentially and multiple-transferred onto this recording sheet 30. In particular, as shown in FIGS. 3 and 4, a pair of Ring body 33 is one tie bar 34
A drum sheet 35 made of, for example, polyvinidene fluoride is stretched over a drum frame 32 connected to the drum frame 32 via a fixing member 36, and the recording sheet 30 is electrostatically attracted by charging the drum sheet 35 in advance. It is. In this embodiment, an adjuster plate 37 for preventing the drum sheet 35 from sagging is disposed adjacent to the tie bar 34 in the opposite rotation direction, and the adjuster plate 37 is provided with a ladder-shaped through hole. 38 is opened, and a recess 39 is formed on the surface of the adjuster plate 37 on the tie bar 34 side, which slopes diagonally downward toward the through hole 38 side, as a space for entry of a peeling finger 47, which will be described later.

Furthermore, in this embodiment, as shown in FIGS. 4 and 5, the approximate center line of the adjuster plate 37 is set as the tip reference PA of the sheet holding surface A, and the distance from the tip reference PA is 180°. The deviated line is set as the leading edge reference PB of the sheet holding surface B, and the recording sheet 30 made of plain paper is normally held on the sheet holding surface A, but in double-hung mode (transfer Holding two recording sheets 30 on a drum 31,
mode in which transfer operation is performed on two recording sheets 30)
In this example, recording sheets 30 made of plain paper are provided on sheet holding surfaces A and B respectively (in this embodiment, JIS standard A
Recording sheets of 4th edition size or smaller) are retained.

In this embodiment, as shown in FIG. 5, the circumferential surface of the transfer drum 31 accommodates a maximum size recording sheet 3 (JIS standard A3 size in this embodiment).
Area S where 0 is held across sheet holding surfaces A to B
In addition, each developing unit 23K of the rotary developing unit 23
It is set to include a region G corresponding to a replacement cycle time of ~23C.

[0031] Also, in this embodiment, OH
The recording sheet 30 made of a P sheet is also used as a single sheet, but when the recording sheet 30 made of an OHP sheet is held on the sheet holding surface A, the leading edge of the recording sheet 30 lifts due to its rigidity, causing tacking errors. Therefore, the position shifted backward by a predetermined distance e (approximately 180 mm in this example) from the tip reference PA of the sheet holding surface A is set so as to become the tip reference PC of the OHP sheet holding surface C. has been done.

Further, the transfer drum 31 has a structure shown in FIGS.
As shown in the figure, when the recording sheet 30 is held, the drum sheet 3
5, a transfer corotron 42 that transfers the toner image on the photosensitive drum 20 to the recording sheet 30 side, and a recording sheet 3 on which the final color transfer process has been completed.
A cleaning static eliminating corotron 44 removes the electric charges on the drum sheet 35 after the transfer process of the final color, and removes paper powder etc. attached to the drum sheet 35 after the transfer process of the final color. A cleaning brush 45 for cleaning, an inner push roll 46 for pushing up the drum sheet 35 from the inside when peeling off the recording sheet 30 held on the sheet holding surfaces B and C, and the recording sheet 30
A peeling finger 47 is provided that peels off the recording sheet 30 alone or pushed up by the inner push roll 46 during peeling. Incidentally, reference numeral 48 denotes a sheet conveying system that conveys the recording sheet 30 supplied from a sheet feeding cassette (not shown) to the suction corotron 41 at a predetermined timing according to each mode.

Further, reference numeral 50 denotes a fixing device through which the recording sheet 30 after the transfer process is inserted and fixing the unfixed toner image on the recording sheet 30. In this embodiment, a heating device with a built-in heater is used. It is composed of a roll 51 and a pressure roll 52 placed in pressure contact with the heating roll 51, and the recording sheet 30 from the transfer drum 31 is conveyed to the fixing device 50 via a guide plate 53. Further, reference numeral 54 indicates the recording sheet 3 that has passed through the fixing device 50.
55 is a fuser exit switch for detecting the trailing edge of the recording sheet 30 that has passed through the fixing device 50; 56 is a discharge tray in which the fixed recording sheet 30 is stored; 57 is a discharge tray to the discharge tray 56; This is an exit roll for sending out the recording sheet 30.

FIG. 6 shows the drive control system of the color copying machine in this embodiment. In the figure, reference numeral 61 is a lamp driver that lights up the exposure lamp 223, 62 and 63 are carriage motors and their motor drivers that drive the carriage 224, and 64 is an IIT that controls the lamp driver 61 and motor driver 63 according to a predetermined exposure sequence. It is a controller.

Further, reference numerals 71 and 72 indicate the photosensitive drums 20.
A drum motor and its motor driver 73 and 74 rotate the transfer drum 31 synchronously, and a developing motor and its motor driver 73 and 74 replace each developing device 23K to 23C of the rotary developing unit 23 and drive a predetermined developing device.
5 and 76 are main motors and their motor drivers for driving the fixing device 50 and sheet conveyance system, and 77 is an IOT controller that controls each motor driver 72, 74, and 76 according to a predetermined development, transfer, and fixing sequence. .

Further, a half-moon-shaped plate 81 is provided coaxially with the transfer drum 31, and an optical sensor 82 consisting of a light-emitting part and a light-receiving part is located across the half-moon-like plate 81.
The output of the optical sensor 82 is repeatedly turned on and off every half rotation of the transfer drum 31, and the edge detection circuit 83 detects the rising and falling points of the output of the optical sensor 82. A reference timing signal TR0 is output for each half-rotation cycle of the transfer drum 31, and this reference timing signal TR0 is input to the IOT controller 77.

Furthermore, reference numeral 91 is a start switch for starting the copying operation, and 92 is a sheet mode selection switch 983 for selecting a single sheet mode or a double sheet mode as a sheet mode.
This is a copy mode selection switch that selects a copy mode (3-color mode, mono-color mode, etc.). Reference numeral 94 indicates various control sequences for the IIT controller 64 and the IOT controller 77 based on the respective switch inputs (in this embodiment, a standard image recording control sequence for each copying mode in the one-copy mode, and This is a SYS controller that requests a special image recording control sequence for each copy mode in the double copy mode.

Next, the operation of the color copying machine according to this embodiment will be explained. ◎Standard Image Recording Control Sequence (Example: 4 Color Mode) FIG. 7 is an explanatory diagram showing a specific example of the standard image recording control sequence. In the figure, first, by turning on the start switch 91 of the user interface (UI), a start copy command is sent to the SYS controller (hereinafter SYS controller).
(abbreviated as S) is given to 94. It is assumed that the single sheet mode is selected from the sheet mode selection switch 92 and the four-color mode is selected from the copy mode selection switch 93.

Then, the SYS 94 sends NBR (Cyc
In response to this, the IOT77 starts cycle up, and when the cycle up is completed, the SYS9
4, the cycle up completion state (State i
nfo Cycle Up).

Then, the IOT 77 issues R0K (instruction not to perform exposure scanning for black K at the next TR0 pitch [R:IOT
Abbreviation for SHEET PLATE REQUEST]
) and H1K (first recording sheet request command for black K [H:IOT NEXT SHEETP
LATE]) is sent to the SYS94, and in response, the SYS94 issues a P1K (first recording sheet permission command for black K [P: abbreviation of SYS PRINT]).
) to IOT77, and IOT77 sends one recording sheet for black K (for example, JIS standard A4 size) 3
0 is fed and supplied to the transfer drum 31 side, and the recording sheet 30 is held on the sheet holding surface A of the transfer drum 31 as shown by the solid line in FIG.

Thereafter, the IOT 77 issues R1K (advance command to perform exposure scanning for black K at the next TR0 pitch) and H0 (advance command to perform exposure scanning for black K at the next TR0 pitch) based on the next reference timing signal TR0.
A non-request command for the second recording sheet) is sent to the SYS94, and in response, the SYS94 sends an Active Re command to the IIT controller (hereinafter abbreviated as IIT) 64.
In addition to transmitting a request (lighting command for the exposure lamp 223), the IO
P0 (instruction to prohibit request for second recording sheet) is transmitted to T77.

Then, as shown in FIG. 8, the IIT 64 turns on the exposure lamp 2 in response to the Active Request.
After lighting 23, the carriage 2
By driving 24, exposure scanning for black K is performed.

On the other hand, the IOT77, as shown in FIG.
After prohibiting the feeding operation of the second recording sheet for black K, the latent image formed on the photosensitive drum 20 is visualized by the developing unit 23K for black K, and this toner image (black K ) is transferred onto the recording sheet 30 held on the transfer drum 31.

Then, the IOT 77 sends R0 (command not to perform exposure scanning for yellow Y at the next TR0 pitch) and H1Y (command requesting the first recording sheet for yellow Y) to SYS based on the reference timing signal TR0.
94, and in response, SYS94 sends Cycl
e Wait (exposure scan pause command) is transmitted to the IIT 64, and P1Y (first recording sheet permission command for yellow Y) is transmitted to the IOT 77.

Then, the IIT 64 turns off the exposure lamp 223 when the exposure scan for black K is completed (so-called back scan), while the IOT 77 turns off the exposure lamp 223
At the stage where the 3K developing operation (developing mode K) is completed, the rotary developing unit 23 is rotated approximately 90 degrees before one rotation cycle of the transfer drum 31 is completed, and the yellow Y
The developing device 23Y is set at the developing position.

Furthermore, based on the next reference timing signal TR0, R1Y (advance command to perform exposure scanning for yellow Y at the next pitch of TR0) and H0 (non-request command for the second recording sheet) are sent to the SYS94. , in response to this,
SYS94 sends Active Req to IIT64
est, and also transmits P0 (instruction for prohibition of requesting the second recording sheet) to the IOT 77 according to the selected one-sheet mode.

Then, as shown in FIG. 8, the IIT 64 turns on the exposure lamp 2 in response to the Active Request.
After lighting 23, the carriage 2
By driving 24, exposure scanning for yellow Y is performed.

On the other hand, the IOT77, as shown in FIG.
The latent image formed on the photosensitive drum 20 is visualized by the yellow Y developing device 23Y, and this toner image (yellow Y
) is transferred onto the recording sheet 30 held on the transfer drum 31.

Then, the IOT 77 sends R0 (command not to perform exposure scanning for magenta M at the next TR0 pitch) and H1M (command requesting the first recording sheet for magenta M) based on the reference timing signal TR0.
Upon receiving this, SYS94 sends Cy
cle Wait (exposure scan pause command) to IIT64
At the same time, P1M (a permission command for the first recording sheet for magenta M) is transmitted to the IOT 77.

Then, the IIT 64 turns off the exposure lamp 223 at the time when the exposure scan for yellow Y is completed (so-called back scan), while the IOT 77 turns off the exposure lamp 223
At the stage where the developing operation (developing mode Y) in Y is completed and before one rotation cycle of the transfer drum 31 is completed, the rotary developing unit 23 is rotated approximately 90 degrees, and the magenta M
The developing device 23M is set at the developing position.

Furthermore, based on the next reference timing signal TR0, R1M (advance command to perform exposure scanning for magenta M at the next TR0 pitch) and H0 (non-request command for the second recording sheet) are sent to the SYS94. , In response to this, SYS94 sends an Active Req to IIT64.
At the same time, it transmits P0 (command for prohibiting a request for the second recording sheet) to the IOT 77 according to the selected one-sheet mode.

Then, as shown in FIG. 8, the IIT 64 turns on the exposure lamp 2 in response to the Active Request.
After lighting 23, the carriage 2
By driving 24, exposure scanning for magenta M is performed.

On the other hand, the IOT77, as shown in FIG.
The latent image formed on the photosensitive drum 20 is visualized by a developing device 23M for magenta M, and this toner image (magenta M) is transferred to a recording sheet 30 held on a transfer drum 31.
to be transcribed.

Then, the IOT 77 sends R0 (command not to perform exposure scanning for cyan C at the next TR0 pitch) and H1C (command requesting the first recording sheet for cyan C) to SYS based on the reference timing signal TR0.
94, and in response, SYS94 sends Cycl
e Wait (exposure scan pause command) is transmitted to the IIT 64, and P1C (first recording sheet permission command for cyan C) is transmitted to the IOT 77.

Then, the IIT 64 turns off the exposure lamp 223 when the magenta M exposure scan is completed (so-called back scan), while the IOT 77 turns off the developing device 2
At the stage where the developing operation (developing mode M) by 3M is completed, the rotary developing unit 23 is rotated approximately 90 degrees before one rotation cycle of the transfer drum 31 is completed, and cyan C is
The developing device 23C is set at the developing position.

Furthermore, based on the next reference timing signal TR0, R1C (advance command to perform exposure scanning for cyan C at the next TR0 pitch) and H0 (non-request command for the second recording sheet) are sent to the SYS94. , in response to this,
SYS94 sends Active Req to IIT64
est, and also transmits P0 (instruction for prohibition of requesting a second recording sheet) and NBR (Cycle Down) to the IOT 77 according to the selected one-sheet mode.

Then, as shown in FIG. 8, the IIT 64 turns on the exposure lamp 2 in response to the Active Request.
After lighting 23, the carriage 2
By driving 24, exposure scanning for cyan C is performed.

On the other hand, the IOT77, as shown in FIG.
The latent image formed on the photosensitive drum 20 is visualized by a cyan C developer 23C, and this toner image (cyan C
) is transferred onto the recording sheet 30 held on the transfer drum 31.

Then, the IOT77 sends R0 (instruction not to perform exposure scanning for black K at the next TR0 pitch) and H0 (recording sheet non-request command) to the SYS94 based on the reference timing signal TR0, and sends these to the SYS94. In response, SYS94 gave Cycle Ou to IIT64.
At the same time as sending t (exposure scan stop command), P is sent to IOT77.
0 (recording sheet non-permission command), and further transmits an image processing system (IPS).
ng System) to stop further image processing (
M/C Stop).

Then, the IIT 64 turns off the exposure lamp 223 when the exposure scan for cyan is completed (so-called back scan), while the IOT 77 turns off the exposure lamp 223 when the exposure scan for cyan is completed (so-called back scan).
At the stage where the developing operation (developing mode C) is completed, the rotary developing unit 23 is rotated approximately 45 degrees before one rotation cycle of the transfer drum 31 is completed, and the developing device 23K is rotated by approximately 45 degrees.
is set at the home position, and when the cyan C transfer process is completed, the recording sheet 30 on the transfer drum 31 is removed by the detack corotron 43, inner push roll 46, and peeling finger 47, as shown in FIG. The film is peeled off, transported to a fixing device 50, subjected to a fixing process, and then discharged to a discharge tray 56.

After that, when the R0, H0 and P0 signals are repeated a predetermined number of times between the SYS94 and the IOT77,
Assuming that the series of copy operations has been completed, the IOT 77 transmits cycle down state information (Cycle Down) to the SYS 94 side.

◎Special Image Recording Control Sequence (Example: 4 Color Mode) FIG. 9 is an explanatory diagram showing a specific example of the special image recording control sequence. In the figure, first, by turning on the start switch 91 of the user interface (UI), a start copy command is sent to the SYS controller (hereinafter SYS controller).
(abbreviated as S) is given to 94. It is assumed that the sheet mode selection switch 92 has selected the two-sheet mode, and the copy mode selection switch 93 has selected the four-color mode.

Then, the SYS94 sends NBR (Cycle Up) and RISC (copy job operation specification) to the IOT 77. In response to this, the IOT 77 starts cycle up, and when the cycle up is completed, the SYS94 cycle-up complete state (S
tate info Cycle Up).

Then, the IOT77 sends R0 (command not to perform exposure scanning at the next TR0 pitch) and H1K (command requesting the first recording sheet for black K) to the SYS94 based on the reference timing signal TR0. ,
In response to this, the SYS94 sends P1K (a permission command for the first recording sheet for black K) to the IOT77, and the IOT77 feeds one recording sheet for black K (for example, JIS standard A4 size) 30. The recording sheet 30 is then supplied to the transfer drum 31 side, and the recording sheet 30 is held on the sheet holding surface A of the transfer drum 31 as shown by the solid line in FIG.

Thereafter, the IOT 77 sends R1K (advance command to perform the first exposure scan for black K at the next TR0 pitch) and H2K (second recording sheet for black K) based on the next reference timing signal TR0. request command) to the SYS94, and upon receiving it, the SYS
94 is an Active Request to IIT64
(lighting command for the exposure lamp 223) and sends a message to the IOT 77 according to the selected double-hook mode.
2K (second recording sheet permission command for black K) is transmitted.

[0066] Then, the IOT 77 issues R2K (advance command to perform the second exposure scan for black K from the next TR0 pitch) based on the next reference timing signal TR0.
and H0 (recording sheet non-request command) to the SYS94, and in response, the SYS94 sends P0 (recording sheet non-permission command) to the IOT 77 without issuing a Cycle Wait (exposure scan pause command) to the IIT64. command).

Then, as shown in FIG.
After lighting the exposure lamp 223 in response to the Active Request, the carriage 224 is driven at a predetermined timing to perform exposure scanning for black K over two pitches.

On the other hand, the IOT 77 suction-holds the second recording sheet 30 for black K on the sheet holding surface B of the transfer drum 31 as shown by the imaginary line in FIG. 6, and as shown in FIG. The latent image formed on the photosensitive drum 20 is visualized by a black K developer 23K, and this toner image (black K) is transferred to a plurality of recording sheets 30 held on a transfer drum 31, respectively. let

Then, the IOT77 sends R0 (instruction not to perform exposure scanning at the next TR0 pitch) and H2Y (command requesting a second recording sheet for yellow Y) to the SYS94 based on the reference timing signal TR0. , In response to this, SYS94 executes Cycle Wait (
At the same time as sending the exposure scan pause command) to the IIT64,
(A permission command for the second recording sheet for Yellow Y) is transmitted to the IOT 77.

Then, as shown in FIG. 10, the IIT 64 turns off the exposure lamp 223 when the exposure scan for black K is completed, while the IOT 77 turns off the developing device 23K.
When the development operation (development mode K) is completed, the rotary development unit 23 is rotated approximately 90 degrees during the next half-rotation cycle (skip: sheet holding surface A) of the transfer drum 31, and the development unit 23Y for yellow Y is rotated by about 90 degrees. Set to the development position.

Furthermore, based on the next reference timing signal TR0, R2Y (advance command to perform two exposure scans for yellow Y from the next TR0 pitch) and H1Y (yellow Y
(request command for the first recording sheet) from the SYS94
In response to this, the SYS94 sends an Active Request to the IIT64, and also sends P1Y(
A command for permission of the first recording sheet for Yellow Y is sent.

Then, the IOT77 sends R1Y (advance command to perform the first exposure scan for yellow Y at the next TR0 pitch) and H0 (recording sheet non-request command) to the SYS94 based on the next reference timing signal TR0. Upon receiving this, SYS94 sends C to IIT64.
P0 (recording sheet non-permission command) is sent to the IOT 77 without issuing a cycle wait (exposure scan pause command).

Then, as shown in FIG.
After lighting the exposure lamp 223 in response to the Active Request, the carriage 224 is driven at a predetermined timing to perform exposure scanning for yellow Y over two pitches.

On the other hand, as shown in FIG. 10, the IOT 77 visualizes the latent image formed on the photosensitive drum 20 with the developer 23Y for yellow Y, and transfers this toner image (yellow Y). The images are transferred onto the recording sheet 30 in this order on the sheet holding surfaces B and A of the drum 31, respectively.

Then, the IOT77 sends R0 (command not to perform exposure scanning at the next TR0 pitch) and H1M (command requesting the first recording sheet for magenta M) to the SYS94 based on the reference timing signal TR0. ,
In response to this, SYS94
(Exposure scan pause command) is sent to IIT64, and P1
M (first recording sheet permission command for magenta M) is sent to the IOT 77.

Then, as shown in FIG. 10, the IIT 64 turns off the exposure lamp 223 when the yellow Y exposure scan is completed, and the IOT 77 turns off the developing operation (development mode Y) by the developing unit 23Y. At the completed stage, during the next half-rotation cycle (skip: sheet holding surface B) of the transfer drum 31, the rotary developing unit 23 is rotated approximately 90 degrees, and the developing device 23M for magenta M is set at the developing position.

Furthermore, based on the next reference timing signal TR0, R1M (advance command to perform the first exposure scan for magenta M from the next TR0 pitch) and H2M (command to request the first recording sheet for magenta M) SY
Upon receiving this, SYS94 sends it to IIT
In addition to sending an Active Request to 64, P is sent to IOT 77 according to the selected double-hook mode.
2M (second recording sheet permission command for magenta M) is transmitted.

Then, the IOT77 sends R2M (advance command for performing the second exposure scan for magenta M at the next TR0 pitch) and H0 (recording sheet non-request command) to the SYS94 based on the next reference timing signal TR0. Upon receiving this, the SYS94 issues a P0 (recording sheet non-permission command) to the IOT77 without issuing a Cycle Wait (exposure scan pause command) to the IIT64.
Send.

Then, as shown in FIG.
After turning on the exposure lamp 223 in response to the Active Request, the carriage 224 is driven at a predetermined timing to perform exposure scanning for magenta M over two pitches.

On the other hand, the IOT 77, as shown in FIG.
The toner image (magenta M) is visualized by a developing device 23M, and the toner image (magenta M) is transferred to the recording sheet 30 in the order of sheet holding surfaces A and B of the transfer drum 31, respectively.

Then, the IOT77 sends R0 (command not to perform exposure scanning at the next TR0 pitch) and H2C (command requesting a second recording sheet for cyan C) to the SYS94 based on the reference timing signal TR0. , In response to this, SYS94 executes Cycle Wait (
At the same time as sending the exposure scan pause command) to the IIT64, the P2C
(First recording sheet permission command for cyan C) is transmitted to the IOT 77.

Then, as shown in FIG. 10, the IIT 64 turns off the exposure lamp 223 when the magenta M exposure scan is completed, while the IOT 77 turns off the developing device 23M.
When the development operation (development mode M) is completed, the rotary development unit 23 is rotated approximately 90 degrees during the next half-rotation cycle (skip: sheet holding surface A) of the transfer drum 31, and the development device 23C for cyan C is rotated by about 90 degrees. Set to the development position.

Furthermore, based on the next reference timing signal TR0, R2C (advance command to perform the second exposure scan for cyan C from the next TR0 pitch) and H1C (command to request the first recording sheet for cyan C) SYS9
4, and in response, SYS94 sends it to IIT64.
In addition to sending an Active Request to
P1C to IOT77 according to the selected double hanging mode
(First recording sheet permission command for cyan C) is transmitted.

Then, the IOT77 sends R1C (advance command to perform the first exposure scan for cyan C at the next TR0 pitch) and H0 (non-request command for recording sheet) to the SYS94 based on the next reference timing signal TR0. Upon receiving this, SYS94 sends N to IIT64.
Send BR (Cycle Down) and IOT77
P0 (recording sheet non-permission command) is sent to.

Then, as shown in FIG.
After turning on the exposure lamp 223 in response to the Active Request, the carriage 224 is driven at a predetermined timing to perform exposure scanning for cyan C over two pitches.

On the other hand, as shown in FIG. 10, the IOT 77 visualizes the latent image formed on the photosensitive drum 20 with the cyan C developer 23C, and transfers this toner image (cyan C). The images are transferred onto the recording sheet 30 in this order on the sheet holding surfaces B and A of the drum 31, respectively.

Then, the IOT 77 transmits R0 (a command not to perform exposure scanning at the next TR0 pitch) and H0 (a recording sheet non-request command) to the SYS 94 based on the reference timing signal TR0, and upon receiving these, SYS94 outputs Cycle Out (exposure scan stop command) to IIT.
64, P0 (recording sheet non-permission command) is sent to the IOT 77, and the image processing system (IPS) is sent to the IOT 77.
:Image Processing System)
A command to stop the subsequent image processing (M/C Stop) is sent to.

Then, the IIT 64 turns off the exposure lamp 223 when the exposure scan for cyan C is finished, and the IOT 77 turns off the exposure lamp 223 when the development operation (development mode C) by the developer 23C is finished. Transfer drum 3
1 next half rotation cycle (skip: sheet holding surface B)
During the process, the rotary developing unit 23 is rotated approximately 45 degrees, the developing device 23K is set to the home position, and when the cyan C transfer process is completed, as shown in FIG. The recording sheet 3 on the transfer drum 31 is removed by the roll 46 and the peeling finger 47.
0 is peeled off, conveyed to a fixing device 50, subjected to a fixing process, and discharged to an output tray 56.

After that, when the R0, H0 and P0 signals are repeated a predetermined number of times between the SYS94 and the IOT77,
Assuming that the series of copy operations has been completed, the IOT 77 transmits cycle down state information (Cycle Down) to the SYS 94 side.

◎Special image recording control sequence (example: 3-color mode) The special image recording control sequence in 3-color mode is basically the same as in 4-color mode, but
Color Unlike the color mode, as shown in FIG. 11, the yellow Y developer 23Y of the rotary developing unit 23 is initially set to the developing position, and the sheet holding surface is Recording sheet 30 for A and B
Transfer a yellow image to the sheet, set the developing device 23M to be replaced in the next half rotation cycle (skip: sheet holding surface A),
Next, after the magenta image is transferred onto the recording sheet 30 in the order of sheet holding surfaces B and A in two half-rotation cycles of the transfer drum 31, the developing device is transferred in the next half-rotation cycle (skip: sheet holding surface B). After replacing 23C and setting,
Two half-rotation cycles of the transfer drum 31 move the sheet holding surface A.
, B to the recording sheet 30, and finally, the developing device 23
The initial value is set to K. Incidentally, when the transfer process is completed, the recording sheet 30 on the transfer drum 31
is peeled off and conveyed to a fixing device, where the toner image on the recording sheet 30 is fixed.

[0090]

[Effect of the invention] As explained above, claim 1
According to the invention described in , 2, a half-rotation cycle of the transfer body is used as a reference cycle for image recording, and a toner image of each color component is transferred to a recording sheet hung on two sheets with two half-rotation cycles relative to the transfer body. The transfer operation is stopped in the next half-rotation cycle, and the developing means is replaced using this pause cycle. It is possible to increase the image recording speed in the dual recording sheet mode while effectively preventing deterioration in image quality due to floating toner.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the configuration of an image recording process control device of an image recording apparatus according to the present invention.

FIG. 2 is an explanatory diagram showing an embodiment of a color copying machine to which the present invention is applied.

FIG. 3 is an explanatory diagram showing details around the transfer drum according to the embodiment.

4 is an explanatory diagram showing details of the VI section in FIG. 3. FIG.

FIG. 5 is an explanatory diagram showing the holding position of the recording sheet with respect to the transfer drum.

FIG. 6 is a block diagram showing a drive control system of a color copying machine according to an embodiment.

FIG. 7 is an explanatory diagram showing a standard image recording control sequence in a four-color color mode according to an embodiment.

8 is an explanatory diagram showing an example of image recording based on the sequence of FIG. 7. FIG.

FIG. 9 is an explanatory diagram showing a special image recording control sequence in a four-color color mode according to the embodiment.

10 is an explanatory diagram showing an example of image recording based on the sequence of FIG. 9. FIG.

FIG. 11 is an explanatory diagram showing an example of image recording based on a special image recording control sequence in three-color mode according to the embodiment.

[Explanation of symbols]

1... Image carrier, 2... Latent image forming means, 3... Developing means, 4...
Recording sheet, 5...Transfer body, 6...Fixing means, 7...Mode selection means, 8...Sheet supply means, 9...Transfer body rotational position detection means, 10...Transfer control means for standard image recording, 11...For standard image recording Development control means, 12... Transfer control means for special image recording, 13... Development control means for special image recording, 14... Sheet peeling means

Claims (2)

[Claims] Claim 1: An image carrier (1) and an image carrier (1).
), a latent image forming means (2) for sequentially forming an electrostatic latent image of each color component on the image carrier (1);
) are selectively arranged around a plurality of developing means (3:3
a, 3b, 3c, 3d) and half-circumferential sheet holding surfaces (A, B) on which two recording sheets (4) are held, and rotates in synchronization with the image carrier (1). A transfer body (which is driven and multiple-transfers each color toner image on the image carrier (1) to the recording sheet (4) held on the sheet holding surface (A, B)
5) and the transfer body (5) after the final color transfer process is completed.
A fixing means (6) for fixing the unfixed toner image on the recording sheet (4) through which the recording sheet (4) peeled from the recording sheet (4) is inserted.
), whether it is a one-sheet mode in which only one recording sheet (4) is held on the transfer body (5) or a two-sheet mode in which two recording sheets (4) are held on the transfer body (5). A mode selection step for selecting one sheet holding surface (A) or one sheet holding surface (A) of the transfer body (5) when the one-sheet mode is selected in this mode selection step.
from the recording sheet (4) to the other sheet holding surface (B).
), and the transfer process of a predetermined color toner image formed on the image carrier (1) during one rotation cycle of the transfer member (5) and the developing means (3:3a, 3b, 3c, 3d). Two recording sheets (4 ) is held, and after the process of transferring a predetermined color toner image formed on the image carrier (1) is repeated twice every half rotation cycle of the transfer member (5), the next transfer member (5) is held. During the half-rotation cycle, only the replacing process of the developing means (3:3a, 3b, 3c, 3d) is performed, and thereafter, the developing means (3:3a, 3b, 3d) is replaced.
3c, 3d) until the replacement process becomes unnecessary.
1) After the transfer process of the predetermined color toner image formed thereon is repeated twice every half-rotation cycle of the transfer body (5), during the next half-rotation cycle of the transfer body (5), the developing means (3:
3. A method for controlling an image recording process of an image recording apparatus, comprising: a special image recording step in which only the replacement steps 3a, 3b, 3c, and 3d) are performed. Claim 2: An image carrier (1) and an image carrier (1).
), a latent image forming means (2) for sequentially forming an electrostatic latent image of each color component on the image carrier (1);
) are selectively arranged around a plurality of developing means (3:3
a, 3b, 3c, 3d) and half-circumferential sheet holding surfaces (A, B) on which two recording sheets (4) are held, and rotates in synchronization with the image carrier (1). A transfer member (which is driven and multiple-transfers each color toner image on the image carrier (1) onto the recording sheet (4) held on the sheet holding surface (A, B)
5) and the transfer body (5) after the final color transfer process is completed.
A fixing means (6) for fixing the unfixed toner image on the recording sheet (4) through which the recording sheet (4) peeled from the recording sheet (4) is inserted.
), whether it is a one-sheet mode in which only one recording sheet (4) is held on the transfer body (5) or a two-sheet mode in which two recording sheets (4) are held on the transfer body (5). a mode selection means (7) for selecting one sheet holding surface (A) of the transfer body (5) or one sheet holding surface (A) of the transfer body (5) when the single sheet mode is selected by the mode selection means (7); The recording sheet (4) is held across from the surface (A) to the other sheet holding surface (B), and the mode selection means (7)
When the two-sheet mode is selected in Transfer body rotation position detection means (9) for detecting the half-rotation cycle of 5)
When the one-coat mode is selected by the mode selection means (7), the image carrier is rotated every rotation cycle of the transfer member (5) based on information from the transfer member rotational position detection means (9). (
1) The predetermined color toner image formed on the recording sheet (4
) and the transfer body rotation position detection means (9) when the one-coat mode is selected by the mode selection means (7). During one rotation cycle of the transfer body (5), the developing means (3)
:3a, 3b, 3c, 3d) for standard image recording development control means (11), and transfer body rotational position detection means ( Based on the information from 9), a predetermined color toner image formed on the image carrier (1) is transferred to the two sheets held on each sheet holding surface (A, B) every half rotation cycle of the transfer member (5). After transferring to the next recording sheet (4), transfer to the next recording sheet (5).
) A special image in which the transfer operation of the transfer body (5) is paused during the half-rotation cycle of the transfer body (5), and thereafter, two transfer operations and one transfer pause operation are continuously repeated for every half-rotation cycle of the transfer body (5). When the two-fold mode is selected by the recording transfer control means (12) and the mode selection means (7), the transfer body (
A special image recording development control means (13) that replaces the development means (3:3a, 3b, 3c, 3d) during the half-rotation cycle when the transfer operation of 5) is at rest, and a final color transfer body (5).
1. An image recording process control device for an image recording apparatus, comprising: a sheet peeling means (14) for peeling off a recording sheet (4) on a transfer member (5) after the transfer operation of the transfer member (5) is completed.