JP3079641B2 - Image recording process control method for image recording apparatus and apparatus therefor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for controlling an image recording process applied to an image recording apparatus for multiplexly transferring each color component toner image on an image carrier onto a recording sheet wound and held on a transfer member. More particularly, the present invention relates to an image recording process control method effective for executing a two-claw mode in which two recording sheets are simultaneously held on a transfer body and an improvement of the apparatus.

[0002]

2. Description of the Related Art Conventionally, as an image recording apparatus of this type, a photosensitive drum as an image carrier and a transfer drum are rotated synchronously, and a toner image of each color on the photosensitive drum is multiplexed on a recording sheet held on the transfer drum. In some cases, a toner image is fixed by a fixing device after the transfer. In such an image recording apparatus, the entire sequence is usually controlled on the basis of the transfer drum (see Japanese Patent Application Laid-Open No. 62-279361). That is, the transfer drum is usually provided with a metal tie bar extending in the drum axis direction as a part of the drum frame, and the transfer operation to the recording sheet cannot be performed at a position corresponding to the tie bar position. The tie bar position serves as a reference for the entire sequence. Exposure scanning, the operation of supplying the recording sheet to the transfer drum, and the operation of aligning the transfer position between the recording sheet held by the transfer drum and the toner image on the photosensitive drum side (within the transfer drum) The on / off operation of the incorporated transfer corotron), the peeling operation of the recording sheet, and the like are controlled.

In this type of image recording apparatus, two sheets holding surfaces A and B on the surface of a transfer drum, for example, have an A4 size based on a demand for high-speed image recording.
The two recording sheets of the plate are sucked and held, and the processes of exposing, developing, and transferring each color component are performed on the two recording sheets in the order of the sheet holding surfaces A and B of the transfer drum. JP-A-2-6984, Color Laser Copier 200 manufactured by Canon Inc.).

[0004]

In such a type, each time the transfer drum makes one rotation, exposure of each color component is performed.
Each process of development and transfer is performed, but after each process of exposure, development, and transfer of the 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 rotation speed of the transfer drum is set high in order to further increase the image recording speed, it is difficult to secure a replacement cycle time of the developing device during one rotation cycle of the transfer drum. Challenges were found.

Means for solving such technical problems include, for example, increasing the diameter of the transfer drum and securing the cycle time for replacing the developing device, or
Although it is conceivable to shorten the replacement cycle time of the developing device, the former type does not meet the demand for downsizing the device itself, and the latter type does not At the time of replacement, a spill phenomenon of the developer is apt to occur, and accordingly, a technical problem that a deterioration in image quality easily occurs due to contamination by floating toner is newly generated.

Conversely, as disclosed in JP-A-63-44670, if the replacement cycle time of the developing unit cannot be ensured during one rotation cycle of the transfer drum, a dummy cycle for one rotation of the transfer drum is set. It is conceivable that the developing device is replaced during this dummy cycle, but in this type, the image recording speed is increased by hanging two recording sheets on the bent transfer drum. There is a situation where it becomes completely useless.

SUMMARY OF THE INVENTION The present invention has been made to solve the above technical problems, and effectively prevents a decrease in image quality due to floating toner due to an increase in size of a transfer member and a reduction in replacement time of a developing unit. It is another object of the present invention to provide an image recording process control method for an image recording apparatus and an apparatus for achieving higher image recording speed in a two-sheet recording mode.

[0008]

That is, as shown in FIG. 1, a method for controlling an image forming process of an image recording apparatus according to the present invention comprises an image carrier 1 and a static image of each color component on the image carrier 1. A latent image forming means 2 for sequentially forming an electrostatic latent image; and a plurality of developing means 3 (for example, 3a, 3b, 3c,
3d), and the two recording sheets 4 are attached to the plurality of developing units 3
The image carrier 1 has a sheet holding surface A and a semicircular surface unit B which are held at intervals smaller than a distance required for the image carrier 1 to move in a time required for the replacement operation of the adjacent developing means 3.
A transfer member 5 that is rotated and driven in synchronization with the recording sheet 4 held on the sheet holding surfaces A and B to transfer the respective color toner images on the image carrier 1 in a multiplex manner, and is transferred after the final color transfer step is completed. Fixing means 6 for inserting recording sheet 4 peeled off body 5 and fixing an unfixed toner image on recording sheet 4
Mode selection that selects between a single-claw mode in which only one recording sheet 4 is held on the transfer body 5 and a two-catch mode in which two recording sheets 4 are held on the transfer body 5 And when the single-stack mode is selected in the mode selection step, the one sheet holding surface A of the transfer body 5 or the one sheet holding surface A to the other sheet holding surface B
And a developing unit 3 (3a, 3b, 3c, 3d) for transferring a predetermined color toner image formed on the image carrier 1 during one rotation cycle of the transfer body 5
When the two-split mode is selected in the standard image recording step in which the exchange step is performed, and in the mode selection step, the two recording sheets 4 are held on the sheet holding surfaces A and B of the transfer body 5, After the transfer process of the predetermined color toner image formed on the image carrier 1 is repeated twice every half rotation cycle of the transfer body 5, the developing unit 3 is rotated during the next half rotation cycle of the transfer body 5.
Only the replacement process of (3a, 3b, 3c, 3d) is performed,
Thereafter, the transfer process of the predetermined color toner image formed on the image carrier 1 is performed every half rotation cycle of the transfer member 5 until the replacement process of the developing means 3 (3a, 3b, 3c, 3d) becomes unnecessary. A special image recording step in which only a step of replacing the developing means 3 (3a, 3b, 3c, 3d) is performed during a half rotation cycle of the next transfer body 5 after being repeated twice. Is what you do.

[0009] An apparatus invention embodying such a method comprises:
As shown in FIG. 1, an image carrier 1, a latent image forming unit 2,
A plurality of developing means 3 (for example, 3a, 3b, 3c, 3d)
If, two of the recording sheet 4 among the plurality of developing means 3
The image forming apparatus includes a transfer member 5 having sheet holding surfaces A and B in a unit of a semi-peripheral surface and a fixing unit 6 that are held at intervals smaller than a distance required for the image carrier 1 to move in a time required for an exchange operation of the adjacent developing unit 3. And a mode selection means 7 for selecting between a single-seat mode in which only one recording sheet 4 is held on the transfer body 5 and a two-seat mode in which two recording sheets 4 are held on the transfer body 5. When the single-piece mode is selected by the mode selection means 7, the recording sheet 4 is transferred 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 supply unit 8 for holding the two recording sheets 4 on each of the sheet holding surfaces A and B of the transfer body 5 when the two-sheet mode is selected by the mode selection unit 7; Transfer Detecting Half Rotation Cycle The rolling position detecting means 9, the mode in one Ding hook mode is selected by the selection means 7, the transfer member rotation position the image bearing member for each one rotation cycle of the transfer member 5 based on information from the detection means 9 a standard image-recording transfer control means 10 for the recording sheet 4 f transferring a predetermined color toner image formed on l, when one Ding seat mode using the mode selection means 7 is selected, the transfer member rotation position The standard image recording development control means 11 for replacing the development means 3 (3a, 3b, 3c, 3d) during one rotation cycle of the transfer body 5 based on the information from the detection means 9, and the mode selection means 7 When the two-fingered mode is selected, a predetermined color toner image formed on the image carrier 1 for each half rotation cycle of the transfer member 5 based on information from the transfer member rotational position detecting means 9 is held on each sheet. The two sheets held on surfaces A and B After the transfer to the recording sheet 4, the transfer operation of the transfer body 5 is stopped during the next half rotation cycle of the transfer body 5, and thereafter, two transfer operations and one transfer every half rotation cycle of the transfer body 5 When the special image recording transfer control means 12 that continuously repeats the pause operation and the two-split mode is selected by the mode selection means 7,
Development control for special image recording in which developing means 3 (3a, 3b, 3c, 3d) is replaced during a half rotation cycle in which the transfer operation of transfer body 5 is stopped based on information from transfer body rotational position detecting means 9. Means 13 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.

In such technical means, as the image carrier 1, a photoreceptor, a dielectric material, or the like may be used as long as it can form a latent image and can carry a toner image obtained by visualizing the latent image. And the like, and the configuration is not limited to a drum shape or a belt shape.

As for the latent image forming means 2, if a latent image corresponding to each color component can be formed according to the type of the image carrier 1, a latent image forming means using a light beam, an ion beam or the like can be used. The latent image to be formed may be read from a document image to form a latent image based on the read image, or may be selected based on an image signal prepared in advance. It can be selected as appropriate, such as forming a latent image.

The developing means 3 also has an image recording mode (for example, a four-color mode, a three-color mode, etc.).
What is necessary is just to prepare a device capable of reproducing colors according to the conditions. The exchange method of the developing unit 3 is also a rotation exchange type (a type in which each developing unit 3 is rotatably arranged and appropriately rotated), and a parallel selection type (image bearing A type that is arranged in parallel around the body 1 and selected as appropriate) may be selected as appropriate.

Further, the structure of the transfer body 5 is such that the recording sheet 4 is held only by the electrostatic attraction force as long as at least two recording sheets 4 can be held at the same time in a two-hook mode. It is also possible to appropriately select, for example, one that is held by the gripper and the electrostatic attraction force. In this case, the sheet holding surfaces A,
Regarding the setting method of B, the section may be set for each half rotation cycle with reference to 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 of the recording sheet 4
It is necessary to select such that the replacement cycle time of the developing means 3 when the value is maintained can be secured.

The mode selecting means 7 has the following features.
When the same color printing or copying is performed on a plurality of recording sheets, it may be that such that the two-seat mode and the one-seat mode are automatically selected,
In addition, the design can be changed as appropriate, for example, by allowing any mode to be arbitrarily selected by a switch or the like.

The sheet supply means 8 includes:
If the transfer sheet 5 holds the recording sheet 4 in accordance with the single-catch mode or the two-catch mode, the design may be changed as appropriate. However, from the viewpoint of increasing versatility, the recording sheets 4 of a plurality of sizes are used. It is preferable to design so that

Further, as the transfer member rotational position detecting means 9, if it can detect at least a half-rotation cycle of the transfer member 5 and can determine the sheet holding surfaces A and B, for example, the transfer member 5 may be coaxial. The edge portion (rising edge, falling edge portion) of the fan-shaped plate is detected by an optical sensor or the like, or a plate that rotates coaxially with the transfer body 5 is provided. A slit may be provided in the portion for discriminating the sheet holding surfaces A and B (for example, the slit position and the number of slits may be different), and the design may be changed as appropriate, such as by optically detecting the slit.

Further, a standard image recording transfer control means 1
The transfer control means 12 and the special image recording transfer control means 12 may be realized by using a microcomputer or the like to realize the respective control functions. However, from the viewpoint of minimizing the destruction of the transferred toner image during multiple transfer. For example, a process for avoiding a situation in which the toner image once transferred to the recording sheet 4 is transferred again to the image carrier 1 at the time of multiple transfer, for example, charging the recording sheet 4 during the transfer operation of the transfer body 5 It is preferable to perform processing such as sequentially increasing the charge amount in accordance with the number of superpositions of the color toner images. Further, the transfer control means for special image recording 12 transfers the toner image holding electric charge to the recording sheet so that the toner image transferred to the recording sheet 4 does not re-transfer to the image carrier 1 even during the transfer pause operation. 4
Preferably.

The control functions of the standard image recording development control means 11 and the special image recording development control means 13 may be realized by using a microcomputer or the like.

The sheet peeling means 14 operates in accordance with the peeling timing of the recording sheet 4 and can be appropriately designed as long as it peels the recording sheet 4 held on the transfer body 5. As long as the peeling performance can be maintained well, a peeling finger, a detack corotron, a sheet extrusion roll for assisting peeling, and the like can be appropriately combined. In particular, in the case of the two-claw mode, the peeling method of the sheet holding surfaces A and B for each recording sheet 4 may be the same or may be designed differently.

[0020]

According to the above-described technical means, when the single mode is selected by the mode selection means 7, the sheet supply means 8 starts the transfer from the sheet holding surface A of the transfer body 5 or one of the sheet holding surfaces A. The recording sheet 5 is held across the other sheet holding surface B.

At this time, the standard image recording transfer control means 1
Reference numeral 0 indicates that a predetermined color toner image formed on the image carrier 1 is transferred to the recording sheet 4 in each rotation cycle of the transfer body 5 based on information from the transfer body rotation position detecting means 9 and the standard image recording is performed. The developing control unit 12 sequentially replaces the developing units 3 (3a, 3b, 3c, 3d) during one rotation cycle of the transfer body 5 based on information from the transfer body rotational position detecting unit 9.

When the double mode is selected by the mode selection means 7, the sheet supply means 8
The two recording sheets 4 are held on the respective sheet holding surfaces A and B.

At this time, transfer control means 1 for special image recording
Reference numeral 2 denotes a sheet holding surface for holding a predetermined color toner image formed on the image carrier 1 for each half rotation cycle of the transfer member 5 based on information from the transfer member rotation position detecting means 9. After transfer to the two recording sheets 4, the next transfer body 5
The transfer operation of the transfer body 5 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 development control means 13
The developing means 3 (3a, 3b, 3c, 3d) is sequentially replaced during a half rotation cycle in which the transfer operation of the transfer body 5 is stopped based on the information from the transfer body rotational position detecting means 9.

In any of the modes, the sheet peeling means 14 peels off the recording sheet 4 on the transfer body 5 after the transfer operation of the final color transfer body 5 is completed, and moves the recording sheet 4 to the fixing means 6 side. Transport.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the embodiments shown in the accompanying drawings. FIG. 2 shows an embodiment of a color copying machine to which the present invention is applied. In FIG.
Is a photosensitive drum, 21 is a charging corotron for pre-charging the surface of the photosensitive drum 20, 22 is an exposure scanning system for writing 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 each accommodating each of the toner images of cyan (C), magenta (M), and yellow (Y) are rotatably arranged, and are appropriately switched and selected; 2
Reference numeral 4 denotes a pre-transfer treatment corotron for removing the potential on the photosensitive drum 20; 25, a cleaner for removing residual toner on the photosensitive drum 20; and 26, an erase lamp for removing residual charge on the photosensitive drum 20.

In this embodiment, the exposure scanning system 22
An exposure lamp 223 for irradiating a light beam to a document 222 set on a platen 221;
224 for moving the document over the area of the document 222
A reflection mirror 225 for guiding a beam from the surface of the document 222 by the exposure lamp 223 along a predetermined path;
A color image sensor 226 that converts a beam from the surface 22 into a digital signal for each color component, an image forming lens 227 that forms an image of the beam from the surface of the document 222 on the color image sensor 226, and the image sensor 226 A laser scanning unit 228 that irradiates a laser beam along the main scanning direction of the photosensitive drum 20 based on an image signal of each color component. The laser scanning unit 228 includes, for example, a semiconductor laser 228a and a polygon mirror 228 that divides and deflects the beam from the semiconductor laser 228a in the main scanning direction of the photosensitive drum 20.
b, the beam from the semiconductor laser 228a is
Imaging lens 2 for imaging along the main scanning direction line 0
28c and a reflection mirror 228d for regulating the beam path.

Reference numeral 31 denotes a recording sheet 30 on the peripheral surface.
(OHP sheet or plain paper) is a transfer drum that wraps and holds the recording sheet 30, and sequentially transfers multiple color component toner images on the photosensitive drum 20 onto the recording sheet 30.
As shown in FIG.
A drum sheet 35 made of, for example, polyvinylidene fluoride or the like is stretched over a drum frame 32 connected by 4 via a fixing member 36, and the recording sheet 30 is electrostatically attracted by charging the drum sheet 35 in advance. Things. In this embodiment, an adjuster plate 37 for preventing the drum sheet 35 from hanging down is disposed at a position adjacent to the tie bar 34 on the side opposite to the rotation direction, and the adjuster plate 37 has a ladder-shaped through hole. 38
Is formed, and a recess 39 is formed on the surface of the adjuster plate 37 on the tie bar 34 side to be inclined downward toward the through hole 38 side as a space for entering a peeling finger 47 to be described later.

Furthermore, in this embodiment, as shown in FIGS. 4 and 5, substantially the center line of the adjuster plate 37 is set as the front end reference P _A of the sheet holding surface A, also from the leading end reference P _A 180 ° deviated line is set as a front end reference P _B of the sheet holding surface B, and the recording sheet 30 made of a plain paper is usually adapted to be held on the sheet holding surface a, two weapons hooking In the mode (a mode in which the two recording sheets 30 are held on the transfer drum 31 and the transfer operation is performed on the two recording sheets 30), the recording is performed using plain paper on the sheet holding surfaces A and B, respectively. The sheet 30 (in this embodiment, a recording sheet of JIS A4 size or smaller) is held.

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

In this embodiment, OH
The recording sheet 30 made of the P sheet is also used as a single sheet. However, when the recording sheet 30 made of the OHP sheet is held on the sheet holding surface A, the leading end of the recording sheet 30 is lifted due to its rigidity, which causes a tacking error. since it and thus, the (approximately 180mm in this example) a predetermined distance e from the front end reference P _a of the sheet holding surface a only as shifted to the rear position is at the tip reference P _C of the OHP sheet retaining plane C Is set to

The transfer drum 31 is provided with
As shown in FIG.
5, a transfer corotron 42 for transferring the toner image on the photosensitive drum 20 to the recording sheet 30 side, and the recording sheet 3 for which the final color transfer step has been completed.
A cleaning corotron 43 for removing the electric charges from the drum sheet 35 after the transfer process of the final color is completed, and a paper dust and the like adhering to the drum sheet 35 after the transfer process of the final color are completed. A cleaning brush 45 for cleaning; an inner press roll 46 for pushing up the drum sheet 35 from inside when the recording sheet 30 held on the sheet holding surfaces B and C is peeled off;
At the time of peeling, a peeling finger 47 for peeling off the recording sheet 30 singly or pushed up by the inner pressing roll 46 is provided. 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 for passing the recording sheet 30 having undergone the transfer step and fixing an unfixed toner image on the recording sheet 30. In this embodiment, a heating device having a built-in heater therein is used. The recording sheet 30 from the transfer drum 31 is conveyed to the fixing device 50 via the guide plate 53 by a roll 51 and a pressure roll 52 arranged in pressure contact with the heating roll 51. Reference numeral 54 denotes a fuser exit roll that conveys the recording sheet 30 that has passed through the fixing device 50, and 55 denotes a fixing device 50.
, A fuser outlet switch for detecting the trailing end of the recording sheet 30 that has passed through, a discharge tray 56 in which the fixed recording sheet 30 is stored, and 57 a recording sheet 30
Is an exit roll for sending out.

FIG. 6 shows a drive control system of the color copying machine in this embodiment. In the figure, reference numeral 61 denotes a lamp driver for turning on an exposure lamp 223; 62 and 63, a carriage motor and a motor driver for driving a carriage 224; and 64, an IIT for controlling the lamp driver 61 and the motor driver 63 according to a predetermined exposure sequence. It is a controller.

Reference numerals 71 and 72 denote photosensitive drums 20.
A drum motor for synchronously rotating the transfer drum 31 and its motor driver; 73 and 74 replace developing units 23K to 23C of the rotary developing unit 23 and drive a predetermined developing unit and a motor driver thereof;
Reference numerals 5 and 76 denote a main motor for driving the fixing device 50 and the sheet conveying system and its motor driver, and reference numeral 77 denotes an IOT controller that controls each of the motor drivers 72, 74, and 76 according to a predetermined development, transfer, and fixing sequence. .

A half-moon plate 81 is provided coaxially with the transfer drum 31. An optical sensor 82 including a light-emitting unit and a light-receiving unit is provided at a position crossing the half-moon 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 rising and falling points of the output of the optical sensor 82 are detected by the edge detection circuit 83. Transfer drum 31
, A reference timing signal TR0 for each half rotation cycle is output, and this reference timing signal TR0 is input to the IOT controller 77.

Further, reference numeral 91 denotes a start switch for starting a copying operation, and reference numeral 92 denotes a sheet mode selection switch 983 for selecting one sheet mode or two sheet mode as a sheet mode.
A copy mode selection switch for selecting a three-color mode, a mono-color mode, etc.). Reference numeral 94 denotes various control sequences for the IIT controller 64 and the IOT controller 77 based on the switch inputs (in this embodiment, a standard image recording control sequence for each copy mode in the single mode, and This is a SYS controller for requesting a special image recording control sequence for each copy mode in the two-claw mode.

Next, the operation of the color copying machine according to this embodiment will be described. Standard image recording control sequence (example: four-color mode) FIG. 7 is an explanatory diagram showing a specific example of the standard image recording control sequence. In the figure, first, when a start switch 91 of a user interface (UI) is turned on, a start copy command is issued to a SYS controller (hereinafter referred to as S).
YS (abbreviated as YS) 94. It is assumed that the single 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 an NBR (Cyc) to an IOT controller (hereinafter abbreviated as IOT) 77.
le Up) and RISC (designation of copy job operation)
Is transmitted, and the IOT 77 starts the cycle-up, and upon completion of the cycle-up, the SYS94
Cycle up completion state (State inf
o Cycle Up).

Based on the reference timing signal TR0, the IOT 77 issues a command [R: IOT not to perform the exposure scan for black K at the next TR0 pitch.
SHEET PLATE REQUEST]) and H1K (H: IOT NEXT SHEETPLATE request command for the first recording sheet for black K) are transmitted to SYS94, and in response, SYS94.
Sends P1K (a command for permitting the first recording sheet to black K [P: abbreviation of SYS PRINT]) to IOT7
7, the IOT 77 feeds one recording sheet (for example, JIS A4 size) 30 for black K and supplies it to the transfer drum 31 side, and as shown by a solid line in FIG. Recording sheet 30 on sheet holding surface A
Hold.

Thereafter, the IOT 77 issues R1K (a notice command for performing an exposure scan for black K at the next TR0 pitch) and H0 based on the next reference timing signal TR0.
(A non-request command for the second recording sheet) is transmitted to the SYS 94, and in response to this, the SYS 94 sends an Active Retry to an IIT controller (hereinafter abbreviated as IIT) 64.
quest (lighting command for the exposure lamp 223) and an IO according to the selected single mode.
At T77, P0 (a request to prohibit the request for the second recording sheet) is transmitted.

Then, as shown in FIG. 8, the IIT 64 sets the exposure lamp 22 in response to the Active Request.
3 is turned on, and the carriage 22 is turned on at a predetermined timing.
4 is driven to perform exposure scanning for black K.

On the other hand, 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 device 23K for black K, and this toner image (black K ) Is transferred to the recording sheet 30 held on the transfer drum 31.

The IOT 77 sends R0 (command not to perform exposure scanning for yellow Y at the next TR0 pitch) and H1Y (command for yellow Y to request the first recording sheet) based on the reference timing signal TR0.
94, and in response to this, SYS 94
e Wait (exposure scanning pause instruction) is transmitted to the IIT 64, and P1Y (a first recording sheet permission instruction for the 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 developing device 2
At the stage when the developing operation by 3K (developing mode K) is completed, the rotary developing unit 23 is rotated by about 90 ° before one rotation cycle of the transfer drum 31 is completed, and the yellow Y
Developer unit 23Y is set at the development position.

Further, based on the next reference timing signal TR0, R1Y (a notice command for performing exposure scanning for yellow Y at the next TR0 pitch) and H0 (a non-request command for the second recording sheet) are transmitted to the SYS 94. In response to this,
SYS94 provides IIT64 with Active Request.
In addition to transmitting st, P0 (a request to prohibit the request for the second recording sheet) is transmitted to the IOT 77 in accordance with the selected single-seat mode.

Then, as shown in FIG. 8, the IIT 64 sets the exposure lamp 22 in response to the Active Request.
3 is turned on, and the carriage 22 is turned on at a predetermined timing.
Exposure scanning for yellow Y is performed by driving No. 4.

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

The IOT 77 sends R0 (command not to perform exposure scanning on magenta M at the next TR0 pitch) and H1M (command for requesting the first recording sheet to magenta M) based on the reference timing signal TR0.
The message is transmitted to the YS 94, and in response to this, the SYS 94
cle Wait (exposure scanning pause instruction) is transmitted to the IIT 64, and P1M (an instruction to permit the first recording sheet to the magenta M) is transmitted to the IOT 77.

Then, the IIT 64 turns off the exposure lamp 223 when the exposure scanning for yellow Y is completed (so-called back scan), while the IOT 77 turns off the developing device 23
When the developing operation by Y (development mode Y) is completed, the rotary developing unit 23 is rotated by about 90 ° before one rotation cycle of the transfer drum 31 is completed, and the magenta M
Developer unit 23M is set to the development position.

Further, based on the next reference timing signal TR0, R1M (preliminary instruction for performing exposure scanning on magenta M at the next TR0 pitch) and H0 (non-request instruction for the second recording sheet) are transmitted to the SYS 94. In response to this, SYS94 sends Active Req to IIT64.
In addition to transmitting the request, the IOT 77 transmits P0 (a request to prohibit the request for the second recording sheet) in accordance with the selected single-catch mode.

Then, as shown in FIG. 8, the IIT 64 sets the exposure lamp 22 in response to the Active Request.
3 is turned on, and the carriage 22 is turned on at a predetermined timing.
Exposure scanning for magenta M is performed by driving No. 4.

On the other hand, 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 recorded on a recording sheet 30 held on a transfer drum 31.
Transfer to

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

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

Further, based on the next reference timing signal TR0, R1C (a notice command for performing an exposure scan for cyan C at the next TR0 pitch) and H0 (a non-request command for the second recording sheet) are transmitted to the SYS 94. In response to this,
SYS94 provides IIT64 with Active Request.
In addition to transmitting st, P0 (a command to prohibit the request of the second recording sheet) and NBR (Cycle Down) are transmitted to the IOT 77 in accordance with the selected single mode.

Then, as shown in FIG. 8, the IIT 64 sets the exposure lamp 22 in response to the Active Request.
3 is turned on, and the carriage 22 is turned on at a predetermined timing.
Exposure scanning for cyan C is performed by driving No. 4.

On the other hand, as shown in FIG.
The latent image formed on the photosensitive drum 20 is visualized by a developing device 23 </ b> C for cyan C, and the toner image (cyan C) is transferred to the recording sheet 30 held on the transfer drum 31.

Then, the IOT 77 sends R0 (command not to perform exposure scanning for black K at the next TR0 pitch) and H0 (record sheet non-request command) to the SYS 94 based on the reference timing signal TR0. In response, SYS94 sends Cycle Out to IIT64.
(Exposure scanning stop command) and P0
(A recording sheet non-permission command), and further, an image processing system (IPS: Image Processing).
System) to stop image processing thereafter (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 developing device 23C.
When the development operation (development mode C) is completed and before one rotation cycle of the transfer drum 31 is completed, the rotary developing unit 23 is rotated by about 45 °, and the developing device 23K is rotated.
Is set to the home position, and when the transfer process using cyan C is completed, as shown in FIG. 3, the recording sheet 30 on the transfer drum 31 is moved by the detack corotron 43, the inner pressing roll 46, and the peeling finger 47. The sheet is peeled, conveyed to the fixing device 50, and discharged to the discharge tray 56 through the fixing process.

Thereafter, when the signals R0, H0 and P0 are repeated a predetermined number of times between the SYS 94 and the IOT 77,
Assuming that a series of copy operations has been completed, the IOT 77 sends the cycle-down state information (Cycle Down) to S
Transmit to YS94 side.

Special Image Recording Control Sequence (Example: Four Color Mode) FIG. 9 is an explanatory diagram showing a specific example of the special image recording control sequence. In the figure, first, when a start switch 91 of a user interface (UI) is turned on, a start copy command is issued to a SYS controller (hereinafter referred to as S).
YS (abbreviated as YS) 94. It is assumed that the double 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 transmits NBR (Cycle Up) and RISC (designation of copy job operation) to the IOT 77, and the IOT 77
When the cycle-up is started, the cycle-up completion state (St
ate info Cycle Up).

Then, the IOT 77 transmits R0 (command not to perform exposure scanning at the next TR0 pitch) and H1K (command for requesting the first recording sheet for black K) to the SYS 94 based on the reference timing signal TR0. ,
In response, the SYS 94 transmits P1K (a command to permit the first recording sheet for black K) to the IOT 77, and the IOT 77 feeds one recording sheet (for example, JIS A4 size) for black K. Then, the recording sheet 30 is 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 a solid line in FIG.

Thereafter, the IOT 77 outputs R1K (a notice command for performing 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. Is transmitted to the SYS 94, and in response to this, the SYS 94
94: Active Request to IIT64
(Lighting command for the exposure lamp 223) and send a P to the IOT 77 in accordance with the selected two-hook mode.
2K (a command for permitting the second recording sheet for black K) is transmitted.

Then, the IOT 77 issues an R2K (preliminary instruction for performing 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 SYS94, and in response, SYS94 issues P0 (recording sheet non-permission) to IOT64 without issuing Cycle Wait (exposure scan pause command) to IIT64. Command)
Send

Then, as shown in FIG.
Is the exposure lamp 2 according to the Active Request.
After turning on 23, the carriage 2 is turned on at a predetermined timing.
By driving 24, the exposure scan for black K is performed over two pitches.

On the other hand, the IOT 77 sucks and holds the second recording sheet 30 for black K on the sheet holding surface B of the transfer drum 31 as shown by a virtual line in FIG. The latent image formed on the photosensitive drum 20 is visualized by a developing device 23K for black K, and the toner image (black K) is transferred to each of a plurality of recording sheets 30 held on a transfer drum 31. Let it.

Then, the IOT 77 transmits R0 (command not to perform exposure scanning at the next TR0 pitch) and H2Y (command for requesting the second recording sheet to yellow Y) to the SYS 94 based on the reference timing signal TR0. In response to this, the SYS 94 transmits a Cycle Wait (exposure scanning pause command) to the IIT 64 and the P2Y
(A command to permit yellow Y to permit the second recording sheet) 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 developing operation (developing mode K) is completed, the rotary developing unit 23 is rotated by about 90 ° during the next half rotation cycle (skip: sheet holding surface A) of the transfer drum 31, and the developing device 23Y for yellow Y is used. Is set to the development position.

Further, based on the next reference timing signal TR0, R2Y (a notice command for performing two exposure scans for yellow Y from the next TR0 pitch) and H1Y (yellow Y
Command for the first recording sheet to the
In response to this, the SYS 94 transmits an Active Request to the IIT 64 and also transmits P1Y (an instruction to permit the first recording sheet for the yellow Y) to the IOT 77 according to the selected two-claw mode. .

Then, the IOT 77 sends R1Y (a notice command for performing the first exposure scan for the yellow Y at the next TR0 pitch) and H0 (a recording sheet non-request command) to the SYS 94 based on the next reference timing signal TR0. In response to this, the SYS 94 transmits P0 (recording sheet non-permission command) to the IOT 77 without issuing a cycle wait (exposure scan pause command) to the IIT 64.

Then, as shown in FIG.
Is the exposure lamp 2 according to the Active Request.
After turning on 23, the carriage 2 is turned on at a predetermined timing.
By driving the drive 24, the exposure scan for the yellow Y is performed over two pitches.

On the other hand, as shown in FIG. 10, the IOT 77 applies yellow Y to the latent image formed on the photosensitive drum 20.
The toner image (yellow Y) is transferred to the recording sheet 30 in the order of the sheet holding surfaces B and A of the transfer drum 31 in the developing device 23Y.

Then, the IOT 77 transmits R0 (command for not performing exposure scanning at the next TR0 pitch) and H1M (command for requesting the first recording sheet to magenta M) to the SYS 94 based on the reference timing signal TR0. ,
In response to this, SYS94 sets the cycle wait.
(Exposure scanning pause command) to the IIT 64 and P1
M (a command to permit the first recording sheet to magenta M) is transmitted to the IOT 77.

Then, as shown in FIG. 10, the IIT 64 turns off the exposure lamp 223 when the exposure scanning for yellow Y is completed, while the IOT 77 performs the developing operation (developing mode Y) by the developing device 23Y. When the transfer is completed, the rotary developing unit 23 is rotated by about 90 ° during the next half rotation cycle (skip: sheet holding surface B) of the transfer drum 31, and the developing device 23M for magenta M is set to the developing position.

Further, based on the next reference timing signal TR0, R1M (preliminary instruction for performing the first exposure scan on magenta M from the next TR0 pitch) and H2M (request instruction for the first recording sheet for magenta M) Is SY
S94, and in response, SYS94 sends IIT
Active Request is transmitted to IOT 77 and POT 64 is transmitted to IOT 77 according to the selected two-split mode.
2M (a command for permitting the second recording sheet to magenta M) is transmitted.

Then, the IOT 77 sends R2M (a notice command for performing the second exposure scan for magenta M at the next TR0 pitch) and H0 (a recording sheet non-request command) to the SYS 94 based on the next reference timing signal TR0. In response to this, the SYS 94 transmits P0 (recording sheet non-permission command) to the IOT 77 without issuing a cycle wait (exposure scan pause command) to the IIT 64.

Then, as shown in FIG.
Is the exposure lamp 2 according to the Active Request.
After turning on 23, the carriage 2 is turned on at a predetermined timing.
By driving 24, the exposure scan for magenta M is performed 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 by the developing device 23M for magenta M, and transfers this toner image (magenta M). The sheet is transferred to the recording sheet 30 in the order of the sheet holding surfaces A and B of the drum 31.

Then, the IOT 77 transmits R0 (command not to perform exposure scanning at the next TR0 pitch) and H2C (command for requesting the second recording sheet to cyan C) to the SYS 94 based on the reference timing signal TR0. In response to this, the SYS 94 transmits a cycle wait (exposure scan pause command) to the IIT 64 and transmits the P2C
(A command for permitting the first recording sheet 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 exposure scan for magenta M ends, while the IOT 77 turns off the developing unit 23M.
When the developing operation (development mode M) is completed, the rotary developing unit 23 is rotated by about 90 ° during the next half rotation cycle (skip: sheet holding surface A) of the transfer drum 31, and the developing device 23C for cyan C is used. Is set to the development position.

Further, based on the next reference timing signal TR0, R2C (preliminary instruction for performing the second exposure scan for cyan C from the next TR0 pitch) and H1C (request instruction for cyan C for the first recording sheet). To SYS9
4 and, in response to this, SYS 94 sets IIT 64
To the IOT 77 according to the selected two-split mode.
(The first recording sheet permission command for cyan C) is transmitted.

Then, the IOT 77 sends R1C (a notice command for performing the first exposure scan for cyan C at the next TR0 pitch) and H0 (a recording sheet non-request command) to the SYS 94 based on the next reference timing signal TR0. In response to this, the SYS 94 transmits an NBR (Cycle Down) to the IIT 64 and transmits the IOT 77
(Recording sheet non-permission command).

Then, as shown in FIG.
Is the exposure lamp 2 according to the Active Request.
After turning on 23, the carriage 2 is turned on at a predetermined timing.
By driving 24, exposure scanning for cyan C is performed over two pitches.

On the other hand, as shown in FIG. 10, the IOT 77 applies a cyan C to the latent image formed on the photosensitive drum 20.
Then, the toner image (cyan C) is transferred to the recording sheet 30 in the order of the sheet holding surfaces B and A of the transfer drum 31 in order.

Then, the IOT 77 transmits R0 (command for not performing exposure scanning at the next TR0 pitch) and H0 (record sheet non-request command) to the SYS 94 based on the reference timing signal TR0. SYS94
Sets the cycle out (exposure scanning stop command) to IIT
P0 (recording sheet non-permission command) is transmitted to the IOT 77 together with the image processing system (IP).
S: Image Processing System
, An instruction to stop the subsequent image processing (M / C Stop) is transmitted.

Then, the IIT 64 turns off the exposure lamp 223 at the end of the exposure scan for cyan C. On the other hand, the IOT 77 turns off the IOT 77 when the developing operation (development mode C) by the developing unit 23C is completed. During the next half rotation cycle of the transfer drum 31 (skip: sheet holding surface B), the rotary developing unit 23 is rotated by about 45 °, the developing device 23K is set at the home position, and the transfer process using cyan C is completed. Then, as shown in FIG.
The recording sheet 30 on the transfer drum 31 is peeled off by the peeling finger 47, and the recording sheet 30 is conveyed to the fixing device 50 and discharged to the discharge tray 56 through the fixing process.

Thereafter, when the signals R0, H0 and P0 are repeated a predetermined number of times between the SYS 94 and the IOT 77,
Assuming that a series of copy operations has been completed, the IOT 77 sends the cycle-down state information (Cycle Down) to S
Transmit to YS94 side.

Special image recording control sequence (example: three-color mode) The special image recording control sequence in the three-color mode is basically similar to that in the four-color mode.
Unlike the color mode, as shown in FIG. 11, the yellow developing unit 23Y of the rotary developing unit 23 is initially set at the developing position, and the sheet holding surface is moved twice in the first half rotation cycle of the transfer drum 31. A and B recording sheets 30
Is transferred to the developing unit 23M in the next half rotation cycle (skip: sheet holding surface A).
Next, the magenta image is transferred onto the recording sheet 30 in the order of the sheet holding surfaces B and A in two half rotation cycles of the transfer drum 31 and then the developing device is moved in the next half rotation cycle (skip: sheet holding surface B). Set exchange of 23C, and then
The cyan image is transferred onto the recording sheet 30 in the order of the sheet holding surfaces A and B in two half rotation cycles of the transfer drum 31, and finally, the developing device 2 is transferred in one rotation cycle of the transfer drum 31.
The initial setting is 3K. When the transfer step is completed, the recording sheet 3 on the transfer drum 31
0 is peeled off, conveyed to the fixing device, and the toner image on the recording sheet 30 is fixed.

[0090]

As described above, according to the first and second aspects of the present invention, a half rotation cycle of a transfer body is used as a reference cycle for image recording, and two cycles are applied to the transfer body.
The transfer operation of the toner image of each color component is performed on the recording sheet that has been hung in two half-rotation cycles, the transfer operation is paused in the next half-rotation cycle, and the developing means is replaced using this pause cycle. As a result, the image recording speed in the two-sheet recording mode can be further increased while effectively preventing the image quality deterioration due to the floating toner due to the enlargement of the transfer body and the shortening of the replacement time of the developing unit. .

[Brief description of the drawings]

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

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

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

FIG. 4 is an explanatory diagram showing details of a VI unit in FIG. 3;

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

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

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

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

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

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

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

[Explanation of symbols]

DESCRIPTION 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 rotation position detection means, 10: transfer control means for standard image recording, 11: 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

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G03G 13/01 G03G 15/01-15/01 117 G03G 15/16 G03G 21/00 370-502 G03G 21/14

Claims (2)

(57) [Claims] An image carrier (1) and the image carrier (1)
A latent image forming means (2) for sequentially forming an electrostatic latent image of each color component thereon; and a plurality of developing means (each including respective color component toners and selectively disposed around the image carrier (1)) 3: 3a, 3b, 3c, 3d) and two recording sheets (4) are adjacent to one another among the plurality of developing means (3).
The image carrier (1) has a sheet holding surface (A, B) in a unit of a semi-peripheral surface which is held at a smaller interval than the moving distance of the image carrier (1) in the time required for the exchange operation of the means (3). a transfer member (5) which is driven to rotate in synchronization with 1) and multiplex-transfers each color toner image on the image carrier (1) onto the recording sheet (4) held on the sheet holding surface (A, B); A fixing unit (6) for inserting the recording sheet (4) peeled off from the transfer body (5) after the final color transfer step is completed and fixing an unfixed toner image on the recording sheet (4). In the image recording apparatus, a mode selection for selecting a single-tick mode in which only one recording sheet (4) is held on the transfer body (5) or a two-tick mode in which two recording sheets (4) are held When the single mode is selected in this mode selection process, The recording sheet (4) is held from one sheet holding surface (A) of the body (5) or from one sheet holding surface (A) to the other sheet holding surface (B), and one of the transfer members (5) is held. A step of transferring a predetermined color toner image formed on the image carrier (l) during the rotation cycle and developing means (3: 3a, 3b,
3c, 3d), when the standard image recording step is performed, and when the two-claw mode is selected in the mode selection step, two sheets are placed on each sheet holding surface (A, B) of the transfer body (5). After the recording sheet (4) is held and the step of transferring the predetermined color toner image formed on the image carrier (1) is repeated twice every half rotation cycle of the transfer body (5), During the half rotation cycle of the transfer member (5), the developing means (3: 3a, 3
b, 3c, 3d), and thereafter, until the replacement of the developing means (3: 3a, 3b, 3c, 3d) becomes unnecessary, the predetermined image formed on the image carrier (l) is removed. Is repeated twice for each half-rotation cycle of the transfer member (5), and during the half-rotation cycle of the next transfer member (5), the developing means (3: 3a, 3b, 3c) And a special image recording step in which only the replacement step of 3d) is performed. 2. 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), and a toner for each color component, respectively. A plurality of developing means (3: 3a, 3b, 3c, 3d) selectively disposed around the image carrier (1); and two recording sheets (4) are provided by the plurality of developing means (3) . Adjacent development
The image carrier (1) has a sheet holding surface (A, B) in a unit of a semi-peripheral surface which is held at a smaller interval than the moving distance of the image carrier (1) in the time required for the exchange operation of the means (3). A transfer member (5) which is driven to rotate in synchronization with 1) and multiplex-transfers each color toner image on the image carrier (1) onto a recording sheet (4) held on the sheet holding surface (A, B); A fixing unit (6) for inserting the recording sheet (4) peeled off from the transfer body (5) after the final color transfer step is completed and fixing an unfixed toner image on the recording sheet (4). In the image recording apparatus, a mode selection for selecting a single-tick mode in which only one recording sheet (4) is held on the transfer body (5) or a two-tick mode in which two recording sheets (4) are held Means (7)
When the single mode is selected by the mode selecting means (7), one sheet holding surface (A) of the transfer body (5) or one sheet holding surface (A) of the transfer body (5) is held by the other. The recording sheet (4) is held across the surface (B), and when the double mode is selected by the mode selecting means (7), each sheet holding surface (A, B) of the transfer body (5) is selected. Sheet supply means (8) for holding two recording sheets (4)
When a transfer member rotation position detecting means for detecting a half-rotation cycle of the transfer member (5) (9), when one Ding hook mode is selected by said mode selecting means (7), transcript rotational position detection Standard image recording for transferring a predetermined color toner image formed on the image carrier (l) to the recording sheet (4) every one rotation cycle of the transfer body (5) based on the information from the means (9) Transfer control means (1
0), when one Ding seat mode using the mode selecting means (7) is selected, in one rotation cycle of the transfer member (5) based on information from the transfer member rotation position detecting means (9) Standard image recording development control means (11) for exchanging development means (3: 3a, 3b, 3c, 3d); and transfer member rotation when the two-claw mode is selected by the mode selection means (7). A predetermined color toner image formed on the image carrier (1) is printed on each sheet holding surface (A, B) every half rotation cycle of the transfer body (5) based on information from the position detecting means (9). After the transfer to the two held recording sheets (4), the transfer operation of the transfer body (5) is stopped during the next half rotation cycle of the transfer body (5), and thereafter the transfer body (5)
The transfer control means (12) for special image recording, which continuously repeats two transfer operations and one transfer pause operation for each half rotation cycle of (1), and the two-claw mode is selected by the mode selection means (7). The developing means (3: 3a, 3b, 3c, 3d) during a half rotation cycle in which the transfer operation of the transfer body (5) is stopped based on the information from the transfer body rotational position detecting means (9).
A special image recording development control means (13) for exchanging the image, and a sheet peeling means (14) for peeling off the recording sheet (4) on the transfer body (5) after the transfer operation of the final color transfer body (5) is completed. An image recording process control apparatus for an image recording apparatus, comprising: