JPH0727292B2 - Recording device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording device for selectively recording black and other colors. An electrophotographic system including a means for forming an electrostatic latent image, a developing device for developing an electrostatic latent image into a visible image, a means for transferring the visible image to a recording sheet, and a cleaning means for cleaning the surface of the photoconductor after the transfer. The present invention relates to a copying machine that selectively supplies a plurality of colors to a developing device to perform color recording.

2. Description of the Related Art Taking a copying machine as an example, one type of conventional color copying machine is one that supplies each color developing solution to one developing device (for example, Japanese Patent Publication No. 54-43898).

Further, there is a mono-color type that is provided with powder developing unit units for the number of colors, one of which is mounted on the main body of the copying machine to perform mono-color copying.

In the former type, since different color liquid developers are supplied to the same developing device, when the recording color is changed, the previous color and the current color are mixed, resulting in a turbid recording. It takes several copies to stabilize in the desired color. Further, when the developer in the developing device is collected in the developer tank, the developer having different colors is collected, and the developer in the developer tank is also soiled.

The latter type has a troublesome work of replacing the developing unit with respect to the main body of the copying machine, has a large number of developing units, and has many mechanical elements, especially elements separated from the main body.

Therefore, in the former type as a simple type color recording apparatus, a cleaning means for cleaning the developing device is provided, and the developing apparatus is cleaned at the time of recording color switching, and then the developing solution for the next recording color is developed. Supplied to the vessel.

By the way, in this type of recording apparatus, a cleaning device for cleaning the photoconductor drum is provided, and the photoconductor drum is cleaned. Further, in this type of color recording apparatus, the black developing solution is supplied to the cleaning apparatus and adheres to the photosensitive drum.
All the toner due to excess development is collected by this cleaning device, and the collected toner is supplied to the black developer tank. Thus, in this type of recording apparatus, the excess toner is recovered by cleaning, but all the recovered toner enters the black developer tank, is mixed, and is reused as black toner. This is because when the color toner is mixed, it becomes black and there is practically no problem.

Therefore, in this type of color recording apparatus, the color toner due to excessive development is recovered as black toner even if color recording is performed, and the developing apparatus is cleaned with a cleaning agent at the time of recording color switching, but the residual toner remains. Since the toner is collected from the photoconductor side through the cleaning device, any residual color toner at the time of recording color switching is collected as black toner.

Therefore, the color toner is substantially not collected as it is, and the color toner is consumed more than it is used for recording. For this reason,
In this type of color recording apparatus, there is a problem that the color toner consumption is large even though the color recording is not performed so much.

Therefore, an object of the present invention is to reduce the consumption of the developer of each color in a recording device that selectively supplies the developer of each color to one developer (for example, a developing device in a copying machine). That is.

In order to achieve the above-mentioned object, in the present invention, in a recording apparatus provided with a developing device for giving a developing agent to a photoconductor: a first tank containing a black developing agent; a developing agent of another color A second tank for supplying the developer from the first tank to the developing device; a second supplying means for supplying the developer from the second tank to the developing device; Switching means for selectively supplying to the first tank, the second tank, and the cleaning agent tank; a color instructing means for instructing a recording color; a state monitoring means for monitoring the agent supply state of the image developing device; When the agent supply state and the indicator color differ from each other, the developer agent being supplied to the image developer is collected, and then the developer of the indicator color is transferred to the image developer apparatus. A developer supply control means for instructing the supply; generating an electric field for attracting the developer of the developing device to the developing device side. Means; and a developer recovery control means for energizing the means for generating the electric field when the developer is supplied to the imaging device.

Here, the developer recovery control unit energizes the bias voltage applying unit that applies a bias voltage to the image forming apparatus and charges the photoconductor when the image forming agent is supplied to the image forming apparatus. Deactivate the charging charger. The bias voltage applying means is an electrode member for applying a bias voltage for preventing the background stain of recording, and this electrode member is specifically a developing roller of the developing device. The developing device is a developing device in a copying machine, and the developing agent is a developing solution in which a dispersant and a toner are mixed in the case of wet development.

According to this, in the recording device that selectively supplies the developing liquid of each color to one developing device, while the developing liquid of each color is being supplied to the developing device, that is, between the developing roller and the photoconductor, While the developer is present, an electric field is applied to the developing device to attract the toner toward the developing device. This electric field is applied by applying a bias voltage for preventing the background stain of recording, and at this time, the charging charger for the photosensitive member is further turned off. This reduces the consumption of toner of each color.

In the developing device of the color recording apparatus, the reason why the bias voltage is applied and the charging charger for the photoconductor is turned off is that the toner does not adhere to the background of the image and the toner is consumed more than necessary. This is to prevent it from being done. This action will be described with wet development. In the developing device, when the background portion of the electrostatic latent image on the photosensitive drum faces the developing roller, the electric field generated by the bias applied to the developing roller causes the toner to move to the developing roller side. This electric field creates a non-uniform state of high concentration of toner on the developing roller side without the toner existing on the photosensitive drum side in the developer of the developing device in which toner is originally uniformly dispersed by this electric field. It is considered to be an action. As a result, even if the excess developer after the next drawing step in the developing section is present in the background portion, it does not appear as background stain on the copy. If no bias is applied in the developing section,
In the excess developing solution after the drawing step, the toner and the dispersant are present at a constant ratio as the developing solution, and the background stain occurs. Due to this background stain, toner is consumed more than necessary. In a recording device that also serves as one developing device and selectively supplies a developing liquid of a plurality of colors to the developing device to perform multicolor copying, supplying the developing liquid of each color only to the developing device and supplying the cleaning device to the cleaning device. Supplies the black developing solution and collects it in the black developing solution tank. Therefore, all the excess developing solution after the drawing process is collected by the cleaning device and is not collected in the developing solution tank of each color. . Therefore, if toner is present in the excess developer, toner will be consumed more than it is consumed in copying.

The amount of excess developer collected by the cleaning device varies depending on the copy pattern, but is about 1 to 5 times the amount consumed by copying. The reason for this is that before the start of development, until the residual liquid is uniformly formed in the developing device,
It is necessary to supply the developing solution, and it is necessary to drain the developing solution to be used especially at the time of color change until the end of copying and until the developing solution is not present between the developing roller and the photoconductor. Since the photosensitive member and the developing roller are rotated while the developing liquid is supplied to these developing devices and while the developing liquid is drained from the developing device at the time of color switching, an excessive developing liquid layer is formed on the photosensitive member. This is because the developer in the surplus developer layer is collected by the cleaning device.

In the present invention, while the developing solution of each color is present between the developing roller and the photoconductor, a bias voltage is applied to the developing roller,
Further, the charging charger is turned off and an electric field for attracting the toner to the developing roller side is applied. Therefore, the amount of toner in the excess developer collected by the cleaning device is extremely small, and most of the excess developer collected is a dispersion liquid. Further, the toner attracted to the developing roller side is peeled off by the scraper blade which is in contact with the developing roller and is collected in the developer tank of each color. Therefore, the consumption amount of each color toner is reduced.

Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings.

[Explanation of Examples]

FIG. 1 mainly shows a mechanical portion of an embodiment of the present invention. This embodiment is a monocolor copying machine.

A document (not shown) placed on the contact glass plate 1 and pressed by the pressure plate 2 is illuminated by the lamp 10. The reflected light of the document is imaged on the surface of the photosensitive drum 3 via the first mirror 11, the second mirror 12, the third mirror 13, the lens unit 14 and the fourth mirror 15. The photosensitive drum 3 is rotationally driven clockwise by a main motor (not shown) via a power transmission mechanism (not shown). Lamp 10 and first mirror 11
Is mounted on a first carriage (not shown), is driven at a constant speed in the direction of arrow A, and has a second mirror and a third mirror.
Mira is mounted on the second carriage (not shown),
It is driven in the direction of arrow A at a speed half that of the first carriage. The surface of the photoconductor drum 3 is the main charger 4
Are uniformly charged at. The charged surface is exposed by the image formation, thereby producing an electrostatic latent image on the surface of the photosensitive drum. This electrostatic latent image is visualized with a developing solution in the developing device 5 to become a visible image. The visible image is 7 parts of transfer charger,
Feed rollers 18 and 2 are fed from cassette 16 by paper feed roller 17.
Paper guides 19, 21 and 6 with 0 and registration roller 22
Is transferred to the recording paper sent along with. The recording paper is separated from the photosensitive drum 3 by the separation unit 8 and guided by the paper guide 23 to enter the fixing device 24, where it receives heat from a heater (not shown) and is then guided by the paper guide 25 and discharged. It is sent out to the paper discharge tray 27 by the paper roller 26. The surface of the photosensitive drum 3 is cleaned by the cleaning unit 9.

The urging control of the mechanical elements described above in various states such as before the start of copying, during the copying cycle, and during the end cycle is well known in a monochromatic (black) recording copying machine and a certain type of full-color copying machine. .

The inside of the developing device 5 is shown in FIG. 2a. The developing device 5 includes an inlet 28 to which a developing solution and a cleaning solution are supplied, and
It has a developer and cleaning solution outlet 29. Container 160
A first developing roller 161, a second developing roller 162, and a squeeze roller 163 are rotatably supported by. These rollers are conductors and are separated from the surface of the photosensitive drum 3 by a very small distance. It is connected to the main motor (not shown) via power transmission means (not shown), and
161 and 162 are driven counterclockwise, and the roller 163 is driven clockwise. These rollers 161, 162 and 163
Is rotating when the photosensitive drum 3 is rotating, and is stopped when the photosensitive drum 3 is stopped. The rollers 161, 162 and 163 have scrapers 164 and 16 respectively.
The free ends of 5 and 166 are in contact so that the scrapers scrape off the developer adhering to the roller surface, while the scrapers 164 and 165 remain on top of the developer or cleaning liquid flowing down from above. The retained liquid wets the surfaces of the rollers 161, 162. This roller 161 and
The liquid on the surface of 162 is attracted by the charges on the surface of the photosensitive drum 3 and moves to the photosensitive drum 3. Then, the roller 163 removes the excess liquid transferred from the photosensitive member to the surface of the drum 3. As a result, the electrostatic latent image on the photosensitive drum is developed.
A bias voltage having a polarity opposite to that of the toner for preventing the background stain of the recorded image is applied to the rollers 161 to 163 during the supply of the developing solution to prevent the toner from being transferred to the surface of the photosensitive drum 3 more than necessary. It Further, in order to effectively prevent the toner from being transferred to the surface of the photosensitive drum 3 more than necessary, the main charger is kept off except when it is necessary for the copying operation.

FIG. 2b shows the inside of the cleaning unit 9. Container 77
Is mounted on a support arm 176 integrated with a frame (not shown) of the main body of the copying machine. The bracket 78 is pivotally attached to a shaft 83 fixed to the frame of the main body. A blade 80 is fixed to one end of the bracket 78, and a sponge roller 79 is pivotally attached to the other end. The squeezing roller 81 is pivotally attached to the frame of the main body. The scraper 84 is in contact with the roller 81, and the liquid scraped off by the roller 81 from the sponge roller 79 is removed by the roller 81. A receiving tray 82 is fixed to a shaft pivotally attached to the frame of the main body. The tray 82 descends on the roller 79 by its own weight. The container 77 has an inlet 40 at the upper end and an outlet 41 at the lower end. The developer in the black developer tank (first tank) 30 is supplied to the inlet 40 by a pump 38. The developing solution that has come to the inlet 40 flows down onto the receiving tray 82, passes along the receiving tray 82, and flows down onto the drum 3 from the free end 82b. Due to this flow, a plunger of a solenoid device (not shown) is connected between the drum 3 and the roller 79 via a developer (not shown), and the solenoid device is energized while the drum 3 is rotating. As shown in FIG. 2b, the blade 80 and the roller 79 are forced to rotate in a direction of being pressed against the drum 3. However, when the drum 3 is stopped, the solenoid device is deenergized and the return spring (not shown) causes the bracket to move. 78 is rotated clockwise about the axis 83, the blade 80 and the roller 79 are separated from the drum 3, and the roller
79 is released from compression of roller 81.

Referring back to FIG. At each port of the inlet 28 of the developing device 5, the discharge port of the first pump 37, the discharge port of the second pump 37r, the discharge port of the third pump 37g, the discharge port of the fourth pump 37b, and the discharge of the cleaning liquid pump 37i. The outlet is connected via a plurality of pipes (not shown). The outlet 29 of the developing device 5 is connected to the inlet of the flow path switching valve 39. The outlet of the switching valve 39 is switched to the nozzle 44 or the first tank (black developer tank) 30. A two-position switching mechanism (not shown) is coupled to the switching valve 39, and the solenoid device 42 drives the two-position switching mechanism. As shown in FIG. 1, the switching valve 39
However, when the solenoid device 42 is energized once while the outlet 29 and the nozzle 44 are connected, the two-position switching mechanism causes the switching valve 39 to operate.
Is driven counterclockwise so that the switching valve 39 moves to the outlet 29-the first tank.
When the solenoid device 42 is energized once in the connected state of the outlet 29 and the first tank 30, the two-position switching mechanism drives the switching valve 39 in the clockwise direction to cause the switching valve 39 to move to the outlet 29. -The nozzle 44 is connected. Thus, the solenoid device 42
The switching valve 39 rotates from one position to the other position and vice versa with each energization. The switching valve 39 is equipped with a position detection switch 43, which is a switching valve.
When 39 is in the outlet 29-nozzle 44 connection, it is closed, and when the switching valve 39 is in the outlet 29-first tank 30 connection state, the switch 43 is open.

The nozzle 44 is rotatably supported by a pulse motor 45. A recovery pipe 47 (47r, 47g, 47b) is arranged below the outlet of the nozzle 44 via a liquid guide (not shown). When the outlet of the nozzle 44 is located on the pipe 47r,
The liquid coming out of the nozzle 44 flows into the second tank (red developer tank) 30r, and when the outlet of the nozzle 44 is located on the pipe 47g, the liquid coming out of the nozzle 44 flows into the third tank (green developer tank) 30g. , When the outlet of the nozzle 44 is located on the pipe 47b, the liquid exiting from the nozzle 44 flows into the fourth tank (blue developer tank) 30b, and when the outlet of the nozzle 44 is located on the pipe 47i, exits from the nozzle 44. The liquid flows into the cleaning liquid tank 30i.
The position of the nozzle 44 is the position detection switch 46 (46r, 46g, 46b, 46
i) detects. Switch 46r is closed when the outlet of nozzle 44 is on pipe 47r, switch 46g is closed when the outlet of nozzle 44 is on pipe 47g, and the outlet of nozzle 44 is pipe 4
Switch 46b is closed when on 7b and switch 46i is closed when the outlet of nozzle 44 is on pipe 47i. Both switches are open when the nozzle 44 is not in the switch position.

At the inlet of the cleaning unit 9, a pump 38 is provided in the first tank 30.
Supply the black developer. The black developer flowing down from the outlet of the unit 9 returns to the first tank 30 through a pipe (not shown).

First tank (black developer tank) 30, second tank (red developer tank) 30r, third tank (green developer tank) 30g and fourth tank (blue developer tank) 30b
A black developing solution container 31, a red developing solution container 31r, a green developing solution container 31g and a blue developing solution container 31b, and diluting solution containers 32, 32r, 32g and 32b, respectively, are attached to each of them. Solenoid devices 33r, 33g, 33b and 33i are connected to the developer containers 31, 31r, 31g and 31b via links. When the solenoid device is energized, the mouth of the developer container is opened and the developer contained therein flows down. The nozzle tip of the mouthpiece of the diluting liquid container 32, 32r, 32g and 32b hits the supporting plate in the tank 30, 30r, 30g and 30b and is raised with respect to the container, so that the mouth of the container is in the tank. is open. When the liquid level in the tank decreases, the diluent flows out of the container into the tank. Cleaning liquid tank
Only the cleaning liquid container 32i is attached to 30i.
The tip of the nozzle of the mouthpiece of the container 32i hits the support plate in the tank 30i and ascends with respect to the container, whereby the mouth of the container is opened in the tank. When the level of the cleaning liquid in the tank 30i decreases, the cleaning liquid flows out of the container into the tank 39i.

For the first tank 30, the second tank 30r, the third tank 30g, the fourth tank 30b, and the cleaning liquid tank 30i, the floats associated with the rise and fall of the liquid level in the tanks and the vertical position of the floats are detected. Upper limit position detection switches 34, 34r, 34g, 34b and 34 for
i, and lower limit position detection switches 35, 35r, 35g, 35b and 35i.

Part of the liquid discharged from the first pump 37 is part of the first concentration detection unit 36.
To the first tank 30 through it. The first detection unit 36 detects the concentration of the black developing solution. The pipe 47r for returning the developer to the second tank (red developer tank) 30r has the second concentration detecting unit 36r, and the pipe 47g for returning the developer to the third tank (green developer tank) 30g has the third concentration detecting unit 36r. Unit 36g is also the 4th
The pipe 47b for returning the developer to the tank (blue developer tank) 30b has a fourth
The concentration detection unit 36b is coupled. These detection units 36, 36r, 36g and 36b include a flow path means for flowing the developing solution in a thin film form, a lamp (36L in FIG. 3) and a photoelectric converter (first part) which face each other with the thin film developing solution in between. 36 of 3
S) is the main component, and the electric circuit configuration is shown in FIG. The electric circuit configurations of the detection units 36, 36r, 36g and 36b are exactly the same.

While the photosensitive drum 3 is rotating, the rollers 161, 162 and 163 of the developing device 5 are also rotating, and the bracket 8 of the cleaning unit 9 is placed at the position shown in FIG. 2b.
The blade 80 and the sponge roller 79 are in pressure contact with the photosensitive drum 3. Further, the pump 38 is energized to supply the black developing solution to the cleaning unit 9.

In the black recording setting state, the switching valve 39 is connected to the outlet 29 and the first tank 30, and the pump 37 is energized to supply the black developing solution to the developing device 5.

In the red recording setting state, the switching valve 39 is set to the outlet 29-nozzle 44 connection state, the nozzle 44 is positioned on the pipe 47r,
The pump 37r is energized to supply the red developing solution to the developing device 5.

In the green recording setting state, the switching valve 39 is set to the outlet 29-nozzle 44 connection state, the nozzle 44 is positioned on the pipe 47g,
The pump 37g is energized to supply the green developing solution to the developing device 5.

In the blue recording setting state, the switching valve 39 is set to the outlet 29-nozzle 44 connection state, the nozzle 44 is positioned on the pipe 47b,
The pump 37b is energized to supply the blue developing solution to the developing device 5.

When changing from the black recording setting state to the red recording setting state, the first pump 37 is de-energized, and after the developer drain time T ₁ , the switching valve 39 is switched to the nozzle 44 side, and the nozzle 44 is placed on the pipe 46i. And the pump 37i is energized during the cleaning time t ₂ . The pump 37i is deactivated after t ₂ ,
After this deenergization, the cleaning liquid is drained time T ₁
44 is positioned on pipe 47r and pump 37r is energized.

Switching from the black recording setting state to the green recording setting state or the blue recording setting state is similarly performed. Further, switching from one of the red recording setting state, the green recording setting state and the blue recording setting state to the other is performed in the same manner, but in this case, the switching valve 39 is not switched.

When switching from red recording setting state, green recording setting state or blue recording setting state to black recording setting state, the recording color appears black even if red, green or blue developing solution is mixed with the black developing solution. In order to shorten the switching time to the high black recording setting state of high, the pump 37r, 37g or 37b is de-energized and the switching valve
39 is switched to the first tank 30 side, and the first pump 37 is energized. No cleaning liquid is supplied to the developing device 5. As a result, the developer drain time T ₁ , the cleaning time t _2, and the cleaning liquid drain time T ₁ are omitted.
However, copying is not started during the time t ₅ from the start of the urging of the first pump 37 until the black developing solution is sufficiently distributed to all the rollers 161, 162 and 163 of the developing device 5.

FIG. 2c shows an operation board 48 provided in the copying machine shown in FIG.
Shows a part of. The elements shown in Figure 2c are as follows:

76: Standby instruction switch with a built-in light emitting element.

When the switch 76 is turned on while the light emitting element is not lit while the power switch (not shown) is turned on, the light emitting element is turned on, the copying machine is in a standby state, and the fixing heater is energized at a low temperature. When the switch 76 is turned on while the light emitting element is on, the light emitting element is turned off, the copying machine enters a copy instruction waiting state, and the fixing heater is energized with high temperature.

49: Copy start switch with built-in red light emitting element and green light emitting element.

In the state of waiting for a copy instruction, the green light emitting element is lit when the copying machine is in the copy ready state, and when the switch 49 is turned on at this time, the copy cycle is started. When the copy cycle is started, the red light emitting element is turned on. The red light emitting element lights up while the set number of copies is being made. When the set number of copies are completed, the red light emitting element goes out and the green light emitting element lights up. During and after copying, when the copying machine is in a copy-disabled state, the green light emitting element is turned off and the red light emitting element is turned on.

SADF: A light-emitting element that lights up when the semi-auto feeder is installed in the copier.

ADF: A light emitting element that lights up when the auto feeder is installed in a copying machine.

Off: A light emitting element that lights up when the feeder is not installed.

Auto Feed: An auto feed indicator switch with a built-in light emitting element.

When this switch is turned on, the light emitting element is turned on, and the copying machine is set to the automatic feed mode in which the original is automatically supplied from the attached feeder onto the contact glass 1. When this switch is turned on while the light emitting element is on, the light emitting element is turned off, and the copying machine is set to the normal mode in which the original is manually placed on the contact glass 1.

Power On: Power indicator.

It lights up when the power switch (not shown) is on, and goes off when it is off.

Interrupt / Resume: An interrupt instruction switch with a built-in light emitting element.

When this switch is turned on while the light emitting element is off, the setting state data of the operation boat 48 and the copy data of the copying machine (the number of copied sheets, etc.) are saved in the memory, and the copying instruction waiting state for the set number of sheets 1 is entered. In this state, the operation board 48 can be changed to an arbitrary setting to instruct copying (interrupt copy setting state). When this switch is turned on while the light emitting element is lit, the data saved in the memory is read, the operation board 48 is set based on the read data, and the internal data of the copying machine, such as the number of copied sheets, is set. Is reset.

51: 3-digit character display.

The copy set number is displayed before the start of copying, and the number of copied sheets is displayed after the start of copying. It is also used to display anomalies.

0-9: Numeric key switch.

Switch for entering the number of copies and other information.

Clear: A switch for entering numeric keys and entering the number of copy settings.

Recall: Switch to read the operation board setting data stored in the previous memory.

55: A light-emitting element for displaying insufficient developer. Lower limit detection switch 35,
Lights when 35r, 35g or 35b is closed.

56: Light-emitting element for displaying insufficient cleaning liquid. Lights when the lower limit switch 35i is closed.

57: A light emitting element for displaying a check instruction.

Lights up when either the upper or lower limit switch is closed, or when there is a paper trouble or mechanical trouble.

53, 53r, 53g, 53b: Color setting indicators.

When the power switch is turned on, 53 is lit and the black recording mode is set.

50: Color instruction switch.

When this switch is turned on while 53 is lit, 53 is turned off and 53b is lit, and the blue recording mode is set. When switch 50 is turned on while 53b is lit, 53b goes off and 53g
Lights up and the green recording mode is set. When the switch 50 is turned on while 53g is lit, 53g is turned off, 53r is lit, and the red recording mode is set. When the switch 50 is turned on while 53r is lit, 53r is turned off and 53 is lit to set the black recording mode.

54: First tank trouble indicator light.

Lights when the upper and lower limit position detection switches 34 or 35 are closed or when the container 31 is empty.

54r: Second tank trouble indicator light.

Lights when the upper / lower limit position detection switch 34r or 35r is closed or when the container 31r is empty.

54g: Third tank trouble indicator light.

Lights when the upper and lower limit position detection switches 34g or 35g are closed or when the container 31g is empty.

54b: Fourth tank trouble indicator light.

Lights when the upper / lower limit position detection switch 34b or 35b is closed or when the container 31b is empty.

54i: Cleaning liquid tank trouble indicator light.

Lights when the upper / lower limit position detection switch 34i or 35i is closed or when the container 31i is empty.

The shaded area around the indicator lamp 54 indicates the illumination area of the paper trouble indicator lamp. Other switches and display elements are mounted on the operation board 48.

FIG. 3 shows an electrical system for energizing the mechanical elements of the copier shown in FIG. Switches such as input switches, status detection switches, and status setting switches for each part of the copying machine 61
The microprocessor 5 via the buffer amplifier 59,60
8 is also connected to the driver 68. At the interrupt input port INT of the microprocessor 58,
A drum sync pulse generator 62 is connected. The pulse generator 62 has a photo sensor 62S that detects a light-transmitting slit of a rotary plate coupled to the photosensitive drum 3. Drum 3
The sensor 62S detects the light-transmitting slit every time when is rotated by a minute angle and gives one pulse to the interrupt input port INT. A temperature detection circuit 63 that detects the temperature of the fixing portion of the fixing unit 24 is connected to the A / D conversion input port AD1 of the microprocessor 58. The thermistor 63 generates a voltage corresponding to the temperature of the fixing portion and applies it to AD1. Microprocessor 58 A
Developer concentration detecting units 36, 36r, 36g and 36b are connected to the / D conversion input ports AD2, AD3, AD4 and AD5, respectively. The photoelectric conversion element 36S generates a voltage corresponding to the concentration of the black developer pumped up by the first pump 37 and applies it to AD2. The lamp 36L gives light to the photoelectric conversion element 36S through the developer thin film. The electric circuit configuration of the units 36r, 36g and 36b is also the same as the electric circuit configuration of the unit 36,
Voltages corresponding to red developer concentration, green developer concentration and blue developer concentration are applied to AD3, AD4 and AD5, respectively. ROM 67, RAM 66, and input / output port buffer elements 64 and 65 are connected to the microprocessor 58 via an address bus, a control bus, and a data bus. Drivers 68 to 71 and drivers 72 to 75 are connected to the input / output port buffer elements 64 and 65, respectively.

The driver 68 sequentially applies a switch state read signal to each of the Y scan lines of the switch matrix 61, and sequentially applies a display element energizing signal to each of the Y scan lines of the display element matrix 76.

Each signal of the X line of the switch matrix 61,
That is, the signal indicating the opening and closing of each switch is buffer 5
Given to the microprocessor 58 via 9,60. Microprocessor 58 applies display element energization signals to each of the X lines of display element matrix 76 via buffers 69, 70, if desired. In the display element matrix 76, the display elements to which the display energizing signal of the Y line and the display energizing signal of the X line are applied simultaneously are turned on. driver
A mechanism drive element (not shown) (main motor, clutch, etc.) is connected to 71, and an electric element (lamp 10, charge 4, 7, etc.) of the image forming system is connected to the driver 72. The driver 73 is connected to electric elements (clutch, motor, etc.) (not shown) of the paper transport system. The driver 74 includes electric elements of the developer supply system, that is, pumps 38, 37, 37r, 37g, 37b, 37i, solenoid devices 42, 33, 33r, 33.
g, 33b and the pulse motor 45 are connected. The driver 75 is connected to a connector for connecting a device mounted on the copying machine, for example, an electric element such as a feeder or a sorter.

The microprocessor 58 gives various energizing signals to the drivers 68 to 75 according to the input operation of various switches and the state of each part of the copying machine. Various control operations of a microprocessor CPU in a copying machine are well known. Therefore, here, the control operation of the microprocessor 58 will be described focusing on the control operation that is closely related to the implementation of the present invention.

FIG. 4a, FIG. 4b, FIG. 4c, FIG. 4d, FIG. 4e and FIG. 4f show the control operation of the microprocessor 58, which is mainly related to the developer supply control.

First, referring to FIG. 1, when a power switch (not shown) of the copying machine is turned on to turn on the microprocessor 58 and each part of the copying machine, the microprocessor 58 executes initialization (step 1: "Step" in parentheses
Is omitted). In this initialization 1, first, each element of the copying machine is set to the inoperative state, and the internal counter, timer, register, etc. of the microprocessor 58 are initialized,
In addition, it initializes the registers etc. for status tracking allocated to RAM. Then, the display of the operation board 48 is set to the standard state, and the data indicating the set state is set in the memory. In the standard state, the copy setting number is 1 and the color is black (the indicator lamp 53 is lit), and the indicator lamp 53 is lit to set the black flag. Then, counting of the elapsed time T is started (time T count start).

Upon completion of this initialization, the microprocessor 58 instructs the heater driver for energizing the heater of the fixing unit 24 to energize the high temperature heat (2). Then switch matrix
The open / closed state of the state detection switch 61 is checked to determine whether copying is possible (3). If it is abnormal, the abnormality process (5) is performed, and it waits until it becomes normal (3-4-5-3). If it is normal or normal, the abnormal flag and the abnormal display are cleared (6), the main motor is turned on (the drum 3 is rotated), and the pump 38 is turned on (the black developing solution is supplied to the cleaning unit 9). (7a). In the developing device 5, the rollers 161 to 163 are rotationally driven in association with the biasing of the main motor and the pump, and the bracket 8 is also driven to move to the position shown in FIG. 2b. 80 and the sponge roller 79 are pressed against the drum 3 (7a). Next, the microprocessor 58 refers to whether or not the time T is equal to or longer than the liquid draining time T ₁ , and if it is less than T ₁ , the fixing unit temperature of the fixing unit 24 (63S output).
(7b). When the time T is less than T ₁ and the fixing unit temperature is less than the set fixing temperature, the process waits until the time T becomes T ₁ or more or the fixing unit temperature becomes more than the set fixing temperature (7b ). When the time T is T ₁ or more, the developing device 5 is sufficiently drained, and when the fixing portion temperature is equal to or higher than the set fixing temperature, copying is possible. Therefore, for cleaning the developing device 5, a microprocessor is used. Reference numeral 58 refers to the state of the switch 43 (8), and when it is not closed (the outlet 29 of the developing device 5 is connected to the first tank 30), energizes the solenoid device 42 during t ₁ (9). . This allows the switching valve
39 is switched to the outlet 29-nozzle 44 connection, and the switch 43 is closed. When the switch 43 is closed or closed, the state of the switch 46i is then referred to (10). Since the nozzle 44 is not on the pipe 47i unless the switch 46i is closed, referring to the states of the other switches 46r, 46g and 46b, the pulse motor 45 is reversely biased to position the nozzle 44 on the pipe 47i ( 11). With this positioning, or the nozzle 44 is on the pipe 47i, and urges the pump 37i between t _2, to clean between the developing device 5 t ₂ (12). this
During t ₂ , the cleaning liquid in the tank 30i is supplied to the developing device 5 and is collected in the tank 30i. At this time, the main charger is biased, but this main charger bias is
This is because the toner in the developer on the surfaces of the rollers 161 to 163 is sucked to the drum 3 side and collected by the unit 9. When the cleaning is completed, the counting of the time T is started and the cleaning completed flag is set (13). That is, the time counting for determining the elapse of the cleaning liquid dead time T ₁ is started.

The above is the developer supply control immediately after the power switch is turned on, that is, the developing device initialization control.

Microprocessor 58 after cleaning (12)
Reads the status of the operation board 48 (14). Operation board 48
If there is no input in, the operation board 48 is waited for, the end cycle end time te elapses, and the key-in waiting time t ₃ elapses in steps 16-17-14. Waiting to do The time te is the end cycle execution time in which the drum 3 is rotated for the post-processing after starting the copy and ending the final copy. When the final copy is completed, the end cycle is started, the timer te (program timer) for the time te is set at that time, and the process returns to step 14. Step 16 is a step for referring to the time-out of the timer te. When the time is over (end cycle end), the end cycle is stopped (18). t ₃ is a set time for automatically returning to the standby state at a certain time when there is no input on the operation board after the copy setting is enabled (step 12).
Copy setting is possible (step 12 and copying of the set number of copies is completed)
When the count value of time T reaches t ₃ after (17),
The fixing heater is switched to preheat activation (low temperature heat activation) (19), the light emitting element of the standby switch 76 is turned on, the main motor is stopped, and the pump 38 is stopped (20). Then, the standby switch 76 waits for turning on (21: standby state). If the standby switch 76 is turned on even when not in the standby state,
This is detected in step 14 and steps 25 to
Proceed to 19 and enter the standby state.

When the standby step 76 is turned on in the standby state (2
1), as in step 7a, the main motor is energized,
The pump 38 is energized (22), the fixing heater is energized with high heat (23) as in step 2, and the operation board is read (14).
Proceed to.

In the operation board reading (14), when an operation of a key switch other than the standby switch 76, the color instruction switch 50, and the start key switch 49 is read (25 to 27), the processing corresponding to the operated key is performed. (28). A typical example of this processing is setting of the number of copies according to the ten-key input.

When the color instruction switch 26 is operated, the microprocessor 58 executes the recording color instruction reading and the overflow processing of the developing device 30 in steps 26 to 4b in FIG. 4a. Explaining these, assuming that the switch 50 is turned on for the first time immediately after the power switch is turned on, the display element 53 is turned on, and the initialization of step 1 causes the register of the microprocessor 58 or the register of the RAM 66 to be turned on. Has a black flag set. Therefore, the microprocessor 58 proceeds to steps 29-31-33-35, clears the black flag and turns off the light emitting element 53, sets the blue flag and turns on the light emitting element 53b at step 35, and performs one switch operation. the so not read more than once, returns to waiting for a time course of t ₄ (36), FIG. 4a of the operation board read through the overflow process of the developing device 30 in step 37 to 41 (14). When the color indicating switch 50 is operated while the blue flag is set, the microprocessor 58 causes the steps 29-31-33.
Go to −34, clear the blue flag in step 34, and
Turns off the 53b, sets the green flag turns on the light emitting element 53 g, waiting time of t ₄ (36), reading operation board of FIG. 4a through overflow process of the developing unit 30 in step 37-41 ( Return to 14). When the color indicator switch 50 is operated with the green flag set, the microprocessor 58
, The process proceeds to step 29-31-32, clear the green flag turns off the light emitting element 53g in step 32, set the red flag, and turn on the light-emitting element 53r, waiting for the time of t ₄ (3
6) After the overflow processing of the developing device 30 in steps 37 to 41, the process returns to the operation board reading (14) in FIG. 4a. When the color instruction switch 50 is operated while the red flag is set, the microprocessor 58 proceeds to steps 29-30,
In step 30 clears the red flag off the light emitting element 53r, set the black flag turns on the light emitting element 53, the overflow processing in the developing unit 30 of the waiting time of t ₄ (36) Step 37-41 After that, the process returns to the operation board reading (14) in FIG. 4a. If the color instruction switch 50 is continuously turned on, the display elements 53, 53b, 53g and 53r are sequentially turned on in this order at time intervals of t ₄ . Therefore, the color instruction switch 50
Either black, blue, green, or red can be specified by continuous on and / or intermittent on.

When the process of reading the recording color instruction (29 to 36) is passed and the process proceeds to the overflow process (37 to 41) of the first tank 30, the microcomputer 58 first refers to the state of the switch 34 (37). As already described, during the rotation of the drum 3, the pump 38 sends the black developing solution to the cleaning unit 9 and the discharged liquid of the unit 9 is collected in the first tank 30 even during copying.
At the time of black recording, the black developer is supplied from the first tank 30 to the developing device 5 and the cleaning unit 9, and these are collected from the developing device 5 and the unit 9 to the first tank 30. Therefore, the developer in the first tank 30 does not substantially increase, but rather the developer decreases due to copying. However, in the case of blue, green or red recording, for example, in the case of red recording, red developing solution is supplied from the second tank 30r to the developing device 5 and its drain is collected in the second tank. Red developer (at this time,
Since the bias voltage for preventing the background stain is applied, there is no red toner, and most of it is the dispersant liquid) is collected by the cleaning unit 9, and the red developer collected by this cleaning unit is Collected in 1 tank 30. Therefore, the amount of liquid in the first tank 30 increases. Therefore, when the switch 34 is closed (the amount of black developer is above the upper limit),
When blue, green, or red recording is performed, the developer may overflow in the first tank 30. The overflow process (37 to 41) of the first tank 30 is a control step for avoiding such overflow in advance. That is, when the switch 34 is closed (the amount of liquid in the first tank 30 is at least the upper limit), (3
7), the first tank trouble indicator light 54 and the operator check indicator light 57 are turned on (39), and the presence or absence of the black flag is referred to (4).
0). If there is a black flag (black recording instruction), there is no problem even if copying is started, so proceed to operation board reading (14: waiting for the start key switch 49 to turn on), but if there is no black flag, a recording instruction for another color is issued. Therefore, clear all the red, green and blue flags, set the black flag (41), turn off the indicator lamps 53b, 53g, 53r and turn on the indicator lamp 53, and proceed to the operation board reading (14). . The operator reduces the developer in the first tank 30 according to the lighting of the indicator lights 55 and 57, and the switch
When 34 is opened and the switch 50 is operated, the microprocessor 58 proceeds to step 14-15-25-26-reading of recording color instruction of FIG. 4b-37-38 and turns off the indicator lamps 54 and 57.
When the switch 37 remains closed, the indicator lamps 54 and 57 are turned on and the recording color is set to black (black flag is set).

When the operation board reading (14 in FIG. 4a) detects that the start switch 49 is closed, the microprocessor 58 executes step 15
After -25-26-27, proceed to step 42 in FIG. 4c. In step 42, the fixing unit temperature of the fixing unit 24 is referred to, and it is determined whether or not it is equal to or higher than the set fixing temperature K. If it is less than K, return to operation board reading (14). When it is less than K, the red light emitting element of the start switch 49 is turned on, and when it is more than K, the green light emitting element is turned on on condition that the copying machine is reading the operation board.

If the temperature of the fixing portion of the fixing unit 24 is equal to or higher than K, the process proceeds from step 42 to step 43 to check the existence of the black graph. If there is a black flag, the black development set in steps 44 to 47 is executed.
That is, the state of the switch 43 is referred to. If the switch 43 is not closed, the switching valve 39 is at the position for supplying the drainage of the developing device 5 to the first tank 30 side, and therefore the process proceeds to the developer adjustment shown in FIG. 4d. When the switch 43 is closed, the switching valve 39 causes the developing device 5 to
Since it is in a position to supply the drainage of the first tank 30
In order to prevent the background stain of the developing device 5, the solenoid device 42 is energized during t ₁ to switch the switching valve 39 to the first tank 30 side (45) and the pump 37 is energized. The bias voltage of is turned on, and the main charger that was turned on during the cleaning process is turned off (46). Then, in order to wait for the black developer from the first tank 30 to reach the rollers 161 to 163 of the developing device 5, wait for time t ₅ to elapse (47), and after t ₅ elapse, the developer adjustment shown in FIG. Proceed to. In this black development set (black recording state setting), waiting for T ₁ to wait for the developing solution to flow down (drain) before the developing apparatus 5, wait for t ₂ to supply the cleaning solution to the developing apparatus 5, and Note that there is no waiting for T _{1 and} waiting for the cleaning liquid to flow down (drain) after t ₂ .

When there is no black flag, the presence or absence of the blue flag is referred to (48). If there is a blue flag, the blue development set in steps 49 to 61 is executed. That is, the state of the switch 43 is referred to (49), and when the switch 43 is closed, the state of the switch 46b is referred to (52). When the switch 43 is closed and the switch 46b is closed, the switching valve 49 is located on the nozzle 44 side and the nozzle
44 is located on the pipe 47b and is in a state in which the drainage of the developing device 5 is supplied to the fourth tank (blue developer tank) 30b. This means that the copy operation immediately before this is the blue copy process. This means that the liquid draining and cleaning of the developing device 5 are unnecessary, and therefore the process proceeds directly to the developing liquid adjustment shown in FIG. 4d. When the switch 43 is not closed, it means that the copy operation immediately before was black copy processing.
After a lapse of T ₁ for judging the flow of the black developing solution from the developing device 5 (50: details are shown in FIG. 4f. Description will be given later), and then t
_{During 1,} the solenoid device 42 is energized to switch the switching valve 39 to the nozzle 44.
Position it to the side (51) and refer to the cleaned flag (54). The presence of the cleaned flag indicates that the copying machine is currently in a state where cleaning of the developing device 5 has been completed. Therefore, if there is a cleaned flag, the nozzle 44 is positioned on the pipe 47b (59), the pump 37b is energized, the bias voltage for preventing the background stain of the developing device 5 is turned on, and the cleaning process is performed. The main charger that was turned on is turned off (60). And
For blue developer waits for spread to the roller 161 to 163 of the developing device 5 waits for the lapse of time t ₅ (61), the process proceeds to the developer regulating of the 4d view when t ₅ has elapsed. If there is no cleaning completed flag in step 54, the developing solution previously contained in the developing device 5 is black, green or red, and the blue developing solution is being supplied this time, so cleaning is necessary. The developing device 5 is cleaned (55). This cleaning (55) has the same contents as the cleaning (11 to 13) of the developing device shown in FIG. 4a. Next, the cleaned flag is set (56) and the time T count is started (5
7). It should be noted that after the cleaning (55) of the developing device 5, the counting of the time T is started as in step 13. Then, the cleaning liquid draining time T ₁ is waited for (58). "Waiting for T ₁ "
The contents of (50,53,58) are shown in Figure 4f. Here, referring to FIG. 4f, the contents of “waiting for the passage of T ₁ ” will be explained. First, since the counting of the time T has already started, this time T 1
It is judged whether or not is T ₁ (102), and if it is not, it waits until it is T ₁ , but while waiting, the operation board is read (103) and input from the operation board. If there is, the process proceeds to step 25 in FIG. 4a and the process according to the input is performed. Therefore, while waiting for the elapse of T ₁ , the switch 50 may be operated to change the recording color designation. In this case, when the recording color designation is changed and the cleaning flag is present, it means that the developing device 5 is in a clean state in which cleaning has been completed.
If there is no cleaned flag, it means that cleaning is required. Here, "Waiting for T ₁ " (50, 53 and 58)
Note that the nozzle 44 is positioned before the positioning (59) and the position of the nozzle 44 has not been changed to the position corresponding to the color flag. "Waiting for T ₁ " (50, 53 and 58: No.
4f)) When the operation of the switch 50 is detected by reading the operation board and the recording color (color flag) is changed, copying is not executed. The developer discharge position before the previous color setting (color flag) was not executed. Since the nozzle 44 is present in the nozzle 44, no error occurs in the positioning control of the nozzle 44. When the recording color (color flag) is changed and there is a cleaned flag, the cleaning process (55) and the cleaning liquid draining time T ₁ wait (58) in steps 55 to 58 are not executed as described above. The cleaning process is not wasted. The time required to start copying after changing the recording color (color flag) is shortened.

When there is no black flag and no blue flag, the presence or absence of the green flag is referred to (62). If there is a green flag, the green development set (63) is executed. This green developing set (63) is also similar to the blue developing set (49-61) described above. However, "46b" in step 52 is "46g" and "47b" in step 59 is "4g".
7g "and" 37b "in step 60 are read as" 37g ".

When there is no black flag, no blue flag, and no green flag, it means that there is a red flag, so the red development set (64) is executed. This red developing set (63) is also similar to the blue developing set (49-61) described above. However,
"46b" in step 52 is "46r" and "47b" in step 59.
“B” is read as “47r”, and “37b” in step 60 is read as “37r”.

When the development set is executed as described above, the pump 37 (step 46), 37b (step 60), 37g (step
Since 63) or 37r (step 64) is activated, cleaning of the developing device 5 is necessary when the recording color is changed next time (however, it is not necessary to change from blue, green or red to black). So clear the cleaned flag (65a),
Proceed to step 65b and subsequent steps for developing solution adjustment.

In developing solution adjustment, first refer to the presence or absence of the blue flag (65
b). With that, now pump 37b is energized and the fourth
The blue developer is supplied from the tank (blue developer tank) 30b to the developing device 5, and the drainage of the developing device 5 is returned to the fourth tank 30b through the concentration detecting unit 36b. Therefore, in this case, blue developer adjustment (66 to 81) is executed. That is, the voltage of the photoelectric conversion element of the concentration detection unit 36b (FIG. 3) is A / D converted,
Compare with the set value (66). When the density indicated by the conversion data is equal to or higher than the set value, the developer density is appropriate. Therefore, the developer supply number n is set (cleared) to 0 (73a) and the state of the switch 35b is referred to (73b). . If the switch 35b is not closed, the developer level in the fourth tank 30b is appropriate, so the trouble indicators 54b, 55 and 57 are turned off (74), the copy number change flag is cleared (75), and step 81 Proceed to. When the switch 35b is closed, the developer is insufficient (at least the diluting liquid container 32b is empty), so the indicators 54b, 55 and 57 are turned on (76), and the number of remaining copies is compared with 99 (7
8). If the remaining number of copies is less than 99, leave it as it is,
If the number of remaining copies exceeds 99, the copy setting number value is updated so that the number of remaining copies is 99 (79), and the copy setting number change flag is set (80). That is, the number of sheets that can be copied thereafter is set to within 99. Step 76
If the copy set number change flag is set when the indicator lamp is turned on at, the copy set number is not changed because the copy set number has already been changed.

As a result of the concentration detection (66), when the concentration is less than the set value, the state of the switch 34b is referred to (68), and when it is closed, the current liquid is supplied from the container 31b to the fourth tank 30b,
Since the developing solution may overflow in the fourth tank 30b, the above-mentioned processing for changing the set number of copies is executed in steps 76 to 80. When the switch 34b is not closed, there is no risk of overflow, so the n value of the number of times of supplying the developer is referred to (69), and if it is less than 5, the solenoid device 33b is energized for the time t ₆ (70). . As a result, during t ₆ , the container 31b is opened and the developer in the container 31b is supplied to the fourth tank 30b. Then, the supplied developer is mixed with the developer in the fourth tank, goes to the developing device 5, and waits for a sufficient time t ₇ to reach the concentration detection unit 36b (72). Change the value of n to a number one larger (72) and detect the concentration (6
6) If the concentration is still low in the concentration detection (66), the developer is again supplied from the container 31b to the fourth tank 30b (69 to 72). When the density becomes higher than the set value, the process proceeds from step 67 to step 73a and exits the developer supply flow. However, even if the developer is supplied five times, the density must be equal to or higher than the set value (there is no developer in the container 31b. Because)
Proceed to steps 76-80 to change the number of copy settings.

When the above developer adjustment is executed and the process proceeds to step 81, the states of the switches 34g, 34r and 34i are referred to there (81).
If 34g, 34r, or 34i is closed here, the positioning of the nozzle 44 is abnormal, and the developer sent to the developing device 5 in the fourth tank (blue developer tank) 30b is discharged from the developing device 5 to another tank. 30r, 30
It may have been sent to g or 30i.
Proceed to. If switches 34g, 34r and 34i are all open, nozzle 44 positioning is considered correct and then switch
Refer to the status of 34 (83). When switch 34 is closed,
During the blue copy, a part of the blue developing solution transferred from the developing device 5 to the drum 3 is collected by the cleaning unit 9 and goes to the first tank (black developing solution tank) 30. There is a risk that the number of tanks will increase and the first tank 30 will overflow. Therefore, if switch 34 is closed, steps 39-41 shown in FIG.
, And proceed to the color setting change already described. When the switch 34 is not closed, the process proceeds to the copy control shown in Fig. 4e.

In the above, the blue developer adjustment when the blue flag is present has been described. Green developer adjustment when there is a green flag (8
4,85) is the same as the blue developer adjustment. However, the steps
"36b" in 66 is "36g", and "34b" in step 68 is "34g".
"g" and "74b" in steps 74 and 76 are "54g"
"33b" in 70 is "33g", and "35b" in step 73b is "35g".
“G” and “34g” in step 81 are read as “34b”. The red developer adjustment (86, 87) when there is a red flag is the same as the blue developer adjustment. However, in step 66, `` 36
“B” is “36r”, “34b” in step 68 is “34r”, “54b” in steps 74 and 76 is “54r”, and “33” in step 70.
"b" is "33r", "35b" in step 73b is "35r",
Also, "34r" in step 81 is read as "34b". The black developer adjustment (88) when there is a black flag is the same as the blue developer adjustment. However, "36b" in step 66 is "36"
"34b" in step 68 is "34", "54b" in steps 74 and 76 is "54", and "33b" in step 70 is "33".
"35b" in step 73b is read as "35", and "34b" is added to step 81. In black copying, the black developer is supplied from the first tank 30 to the developing device 5, the waste liquid of the developing device 5 is returned to the first tank 30, and the recovery liquid of the unit 9 is also first.
Since it is returned to the tank 30, the amount of the developer in the first tank 30 does not increase, but rather decreases. Therefore, copying can be started or continued even when the switch 34 is closed. So in black developer adjustment,
If all the switches are not closed in the switch state determination corresponding to step 81, step 83 does not pass and the process directly proceeds to the copy control of FIG. 4e.

The copy control will be described with reference to FIG. 4e. First, the key-in reading of the operation board 48 is set (89), and one copy cycle is started (90). In this one copy cycle, one well-known copying process is performed in a normal copying machine. In this copy cycle, the main charger is activated at the required timing and deactivated at the unnecessary timing.
If there is a key-in on the operation board 2c during this copying process,
The data indicating the input key switch is stored in the memory. When the key-in is the color instruction switch 50, the color flag at that time is saved as the previous color flag, and the process of FIG. 4b is executed. When this is executed, the color currently being copied (previous color flag) and the color flag that has just been set are different. When one copy cycle (90) is completed, refer to whether the color flag has been changed (9
2) If it has not been changed, the content of the number-of-copied-sheets register is updated by 1 (93), and the content of the register is compared with the content of the copy-set number-of-sheets register (94). If the number of copied sheets does not exceed the set number, copy processing (90)
Is necessary, read the state of each part of the copier (95),
It is determined whether or not the copy process can be continued (96), and if it cannot be continued, the process proceeds to the abnormal process (97). If it can be continued, the process goes to the head (89) of the copy control again. If the number of copied sheets exceeds the set number, or if the color flag is changed during one copy cycle (90), the end cycle for post-processing is set (98) and the end cycle end judgment is made. In order to set the te time limit timer (99), the pumps 37, 37r, 37g and 37b for supplying the developing solution are deactivated, and the developing device 5
Turn off the bias voltage to prevent the background dirt from
0), start counting time T (101). And 4a
Return to operation board reading (14) in the figure. Pump 37,37r, 3
By deactivating 7g and 37b, the supply of the developing solution to the developing device 5 is stopped, and the developing solution of the developing device 5 is stored in the developing solution tank.
Run down to 30,30r, 30g or 30b by its own weight. That is, draining of the developing solution has started. Therefore, the count value of the time T indicates the liquid draining duration time. It also shows the elapsed time from the end of copying.

When the copying is completed and the operation board reading (14) is resumed as described above, Steps 14-15-16-17-14 will be executed.
Wait for the operation board 48 there is input, the end cycle is completed wait for (the timer te to time over), also, wait for the passage of time t _3. Note that t ₃ > te. If there is an input on the operation board 48 before the elapse of te, the above-mentioned control of step 25 and thereafter is started. There is no input on the operation board 48
When te elapses, the end cycle is stopped (18). When the end cycle is stopped, the rotation of the drum 3 is stopped, other mechanical parts are stopped, and the pump 38 is deenergized. After that, when t ₃ elapses, the standby state is set (19, 20) and then the standby switch 76 is waited for being turned on (21). Standby switch 76
Is turned on, the main motor is rotated to energize the pump 38 (22), energize the fixing heater with high heat (23), and proceed to operation board reading (14).

The main control operation of the microprocessor 58 described above is summarized as follows.

(1) Recording color black setting when the power is turned on. The black flag is set by initialization immediately after power-on (2), and black recording is first set in the memory. It is estimated that this type of copying machine has the highest probability of black recording copy. Therefore, the recording color in the standard copy conditions is black. However, the setting of another color may be instructed by the subsequent operation board input, and if the supply of the black developing solution to the developing device 5 is started, the supply of the black developing solution is stopped and the black developing solution is not supplied. The liquid-draining standby T ₁ , the cleaning t _2, and the cleaning liquid draining standby T ₁ are required, and the operating efficiency of the copying machine is reduced. Therefore, even if the recording color black is set on the memory, the developing solution is not supplied to the developing device 5.

(2) Standby immediately after the power is turned on. When the power is turned on, counting of the time T is started (2), and the process waits until the time T reaches T ₁ or the fixing unit temperature of the fixing unit 24 reaches the fixing temperature (7b).

By the time the power is turned on, the drain time T ₁ of the developer used for the previous copying may have passed or may not have passed. It is explained to the operation manual and others so that the power of the copying machine is turned off after the end cycle is completed. With normal power off (power off after the end cycle ends), T ₁ has passed before the power is turned off. Therefore, when the power is turned on again, it is not necessary to set the drainage time T ₁ . However, although the probability is low, it is possible that the power is turned off during copying or immediately after the end of copying, and then the power is turned on again before the lapse of T ₁ . Therefore, in this embodiment, as a general rule, the liquid draining time of T ₁ is uniformly set after the power is turned on. When the power is turned on when the fixing unit 24 is at room temperature, the fixing portion temperature rises to the set fixing temperature. Is longer than T ₁ . Therefore, even if the draining time of T ₁ is set immediately after the power is turned on, the operating efficiency of the copying machine is not particularly lowered. However, when the power is shut off after an end cycle after the end of the previous copy, and then the power is turned on again immediately (the probability that the power is turned on in this mode is high), the fixing unit temperature is high and usually the previous copy is performed. Since the liquid-off time T ₁ has elapsed since the end, T ₁ has not elapsed since the power was turned on.

(3) Cleaning after the developer is drained. The developer in the developing device 5 has sufficiently flown out during the standby in (2) above. Immediately after the standby, the key-in of the operation board 48 does not always occur immediately, and it is unknown what the recording color is designated. If the power of the fixing unit 24 is turned on when the fixing unit 24 is at room temperature (such as the first power-on in the morning), the fixing unit temperature has not yet risen to the fixing temperature at this stage. Waiting for warm-up. Therefore, the developing device 5 is cleaned at this stage (12). At least during this cleaning, the main charger 4 is urged to attract the toner of the roller of the developing device 5 to the photosensitive drum 3 and remove it from the roller. The toner of the roller of the developing device 5 is attracted to the photosensitive drum 3 by the bias of the main charger 4, so that the cleaning liquid is less contaminated.

(4) Standby for drainage after cleaning. When the cleaning is completed, the time T ₁ required for the cleaning liquid to sufficiently flow out from the developing device 5 is awaited. During this time, the operation board is read (13, 14).

(5) Recording color setting. By reading the operation board (14,103),
When the operation of the color instruction switch 50 is read, the recording color is set correspondingly (29 to 41). In this recording color setting,
When the level of the developer in the black developer tank 30 is equal to or higher than the upper limit, only black is set without setting the recording color other than black. This is to prevent the developer in the first tank 30 from overflowing.

(6) Start switch 49 by reading the operation board (14,103)
When the operation of is read, the developing set (42 to 64: supply of the developing solution to the developing device 5) is performed under the condition that each part of the copying machine except the developing system is ready for copying, and then the developing solution adjustment (65b to 8
After performing 3), proceed to copy processing (89 to 101).

(7) In the developing set of (6) above, the actual developer supply setting state is compared with the developer supply required this time. (7-1) If they match, the process proceeds to developer adjustment. As a result, when the recording color designation is not changed, the copying operation is promptly started in response to the operation of the start key switch, as in a normal monochrome copying machine. When the two do not match, (7-2A) when the color of the developer supply setting required this time is red, green, or blue, (7-2A-1) wait for the draining time T ₁ of the previously used developer to elapse ( 50, 53), then cleaning is carried out (55), and then the depletion time T ₁ of the cleaning liquid is awaited (58).
Then, the process proceeds to developing solution adjustment.

(7-2A-2) When there is a cleaned flag,
Since the developing device 5 has just been cleaned, the waiting time for draining time T ₁ of the developer used last time (50, 53) and the execution of cleaning (55) are omitted, and the draining time T ₁ of the cleaning liquid elapses. Wait for (58).

(7-2A-3) While waiting for the elapse of the drainage time T ₁ , the operation board reading (103) is performed, and if there is an input,
Proceed to (5) above.

(7-2B) If the color of the developer supply setting required this time is black, the above (7-2A-1), (7-2A-2) and (7-
Do not execute 2A-3). Therefore, the time from the black instruction input operation to the start of black copying is significantly shorter than that for other colors. This is similar to the case of a normal monochrome copying machine.

(7-3) The developer supply pump 37, 37r, 37g or 37b is energized, and at the same time, a bias voltage for preventing the background stain of the image is applied to the developing roller of the developing device 5 (46, 60). As a result, a predetermined developer is supplied to the developing device 5, and it is necessary to perform cleaning again at the time of recording color switching, so the cleaning completed flag is cleared at this time (65a).

(8) In the developer adjustment of (6) above, when the developer concentration is insufficient, the developer is supplied from the developer container to the developer tank. Then change the value so that the actual number of copies is 99 or less. Also, when the developing solution level in the developing solution tank is low, the copy setting number is similarly changed. This is done in order to limit the number of subsequent copies to 99 when the concentration of the developing solution is insufficient and the amount of the developing solution is insufficient, so that the number of copies is acceptable.

(9) In the developer adjustment of (6) above, if the liquid levels of the developer tank and the cleaning solution tank that store a developer of a color different from the set recording color exceed the upper limit, the recovered developer will If the supply direction is abnormal (switching abnormality of the switching valve 39 or positioning abnormality of the nozzle 44), the process proceeds to abnormality processing and the copy is not started.

(10) In the developer adjustment of (6) above, the setting color is red,
When the developer level in the black developer tank 30 is equal to or higher than the upper limit when the color is green or blue (83), the set color is changed to black and the operation board reading (14) is returned to. When the setting color is black, the setting color is not changed and the operation board reading is not resumed. This is done to prevent overflow of the first tank 30.

(11) The operation board is read even during one copy cycle, and if there is an input, it is stored in the memory. After the completion of one copy cycle, referring to the memory, if the recording color instruction is changed (92), the end cycle is set and the process returns to the operation board reading (14).

(12) When copying is completed, the timer is set to determine the end of the end cycle (99), the developer supply pump is turned off, and the bias voltage for preventing the background stain of the image applied to the developing device 5 is set. Turn off (100). And for counting the unused (unused) time after copying,
Further, time T counting is started to monitor the outflow (draining) of the developing solution in the developing device 5 (101). Developing device 5
The developing solution supply system to and the developing solution recovery system from the developing device 5 are not reset (initialized), and are left as they are. this is,
There is a high probability that a copy of the same color will be instructed next, and if initialization is performed at this time, there is a high probability that you will have to wait for liquid to drain, clean, etc., to prevent such waste. is there.

After that, when there is no operation board input (start switch 49 ON) and the timer te elapses, the end cycle is stopped (rotation of the drum 3 etc.) (18), and when there is no operation board input and the set waiting time t ₃ elapses, The copying machine is put into a standby state (such as the low heat generation of the fixing heater) (19 to 21). When in the standby state, the operation board reading (14) does not proceed unless the standby switch 76 is operated (21 to 23). When the switch 76 is operated to proceed to the operation board reading (14) before the standby state is entered or during the standby state, the recording color is changed (from black to red, green or blue, or red, red,
Change of recording color from green or blue to other colors (except black)]
, The time T count value started at the end of copying is referred to and the condition is that it becomes T ₁ or more (50,5
Cleaning starts at 3) (54, 55). Therefore, the counting start (101) of the time T after the end of copying has the effect of making the waiting time shorter than the case of newly setting the liquid drain waiting time when the recording color is changed thereafter.

(13) During cleaning (12,55), read the operation board (1
4, 103) is not executed, and waits for draining before or after cleaning 5
At 0, 53, 58), operation board reading (103) is executed. This is because the cleaning time t ₂ is relatively short (for example, t ₂ is
5 seconds), so it doesn't take a long time to wait for this to end,
Moreover, since any recording color can be set after cleaning, it is rational that once the cleaning is started, it is completely finished. Also, the waiting time for drainage
T ₁ is relatively long (for example, T ₁ is about 15 seconds), and the operator may want to change the recording color during that time, so the operation bow reading (103) is executed, and if there is an operation board input, the operator responds accordingly. Even if the treatment is performed, it is sufficient to continue counting the time T during that time, and the continuity of the liquid drain standby can be maintained.

(14) When cleaning (12, 55) is executed, the cleaning completed flag is set to indicate that the developing device 5 is still being cleaned. After that, the developer supply pump
When the 37, 37r, 37g or 37b is energized, the cleaned flag is cleared (65a). And in recording color switching (switching to a different color except switching from red, green or blue to black),
When the cleaning completed flag is present, the liquid supply standby and cleaning of the predevelopment liquid are omitted, and only the cleaning liquid supply standby is performed to start the supply of the new developer. This is effective in shortening the waiting time. Especially, when the recording color designation is changed by the operation board reading (103) in the cleaning liquid drain standby (58), the changed color development set (48 ~
In 65a), there is an effect of shortening the waiting time before the start of copying.

Next, another embodiment of the present invention will be described. In the above example,
When the developing solution is supplied to the developing device, a bias voltage is applied to the developing roller of the developing device to prevent the background stain of the image. This is to prevent the toner in the developing solution from being unnecessarily sucked by the photosensitive drum and not collected from the cleaning device, thereby reducing the toner consumption. In particular, when the color toner due to excess development is collected from the photoconductor drum by the cleaning device, the color toner is collected in the black developer tank, so that the amount of consumption of the colorner increases. Therefore, when the developing solution is being supplied to the developing device, a bias voltage is applied to the developing device. However, there is no particular problem even if the bias voltage for preventing the background stain of the image is continuously applied when the developing solution is not supplied to the developing device, so that the application of the bias voltage can be easily controlled. Therefore, the bias voltage may be applied to the developing device while the power of the color recording device is turned on. This simplifies the control and simplifies the configuration.

The copier described with reference to the drawings is a monochromatic color copier. In another embodiment of the present invention, a paper transport mechanism for selectively guiding the paper from the exit of the fixing device 24 to the entrance of the registration roller 22 is provided, and a plurality of paper feeding mechanisms are provided between the photosensitive drum 3 and the mirror 15. A filter unit consisting of a filter plate is placed to make a full-color copier. In this case, when full color is designated, one copy of the recording paper is returned from the fixing device 24 to the registration roller 22 in a predetermined order, for example, a copy of cyan C, magenta M, and yellow in a predetermined order. Moreover, the filter units in the exposure optical path of the filter unit are sequentially switched while switching. As described above, the present invention can be directly applied to a full-color copying machine. In such a full-color copying machine, when the present invention is carried out, the consumption of color toner not related to recording is reduced, and the effect is great.

As described above, according to the present invention, in a recording device that selectively supplies each color developing agent to one developing device, when the developing solution is supplied to the developing device, the background of the image is smeared on the developing roller. Since the bias electric field for prevention is applied to reduce the consumption of the toner of the recording color, the consumption of the developer of each color can be reduced. Therefore, when the present invention is carried out in a full-color copying machine, the consumption of color toner not related to recording is reduced, and the effect is great.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram mainly showing the structure of a mechanical portion of an embodiment of the present invention, FIG. 2a is a sectional view showing the inside of the developing device 5 shown in FIG. 1, and 2b. 1 is a sectional view showing the inside of the cleaning unit 9 shown in FIG. 1, and FIG. 2c is a plan view showing a part of the operation display board of this embodiment. FIG. 3 is a block diagram showing the configuration of the electric control system of this embodiment. 4a, 4b, 4c, 4d, 4e and 4f are flow charts showing the control operation of the microprocessor 58 shown in FIG. 1: Contact glass, 2: Pressure plate 3: Photosensitive drum, 4: Main charger 5: Developing device (visualizing device) 7: Transfer charger 8: Separation unit 9: Cleaning unit 10: Lamp 11,12,13,15 : Mirror 14: Lens unit, 16: Recording paper cassette 17: Paper feed roller, 22: Registration roller 24: Fixing unit, 27: Paper discharge tray 28: Liquid inlet of developing device, 29: Liquid outlet 30: Black developer tank (First tank) 30r: Red developer tank (second tank) 30g: Green developer tank (second tank) 30b: Blue developer tank (second tank) 30i: Cleaning solution tank 31,31r, 31g, 31b : Developer container 32, 32r, 32g, 32b: Diluent container 32i: Cleaning liquid container 33, 33r, 33g, 33b, 42: Solenoid device 34, 34r, 34g, 34b, 34i: Upper limit detection switch 35, 35r, 35g , 35b, 35i: Lower limit detection switch 36, 36r, 36g, 36b: Developer concentration detection unit 37: Developer supply pump (first supply means) 37r, 37g, 37b: Developer supply pump (second supply means) 37i : Cleaning liquid Supply pump 38: Drum cleaning liquid supply pump 39: Switching valve 44: Switching nozzle (39,44: Switching means) 40: Drum cleaning liquid inlet 41: Drum cleaning liquid outlet 43: Position detection switch 45: Pulse motor 46 : Nozzle position detection switch (43,46,58: Status monitoring means) 47: Recovered liquid receiving pipe 48: Operation board 49: Start switch 50: Color instruction switch (color instruction means) 51: 3 digit segment display 53,53b, 53g, 53r, 54,54r, 54g, 54b, 54i, 55,56,57: Indicator light 58: Microprocessor (developer supply control means, developer recovery control means) 161,162,163: Roller (electrode member, electric field Means to occur)

Claims (6)

[Claims] 1. A recording apparatus comprising a developing device for giving a developing agent to a photoconductor: a first tank containing a black developing agent; a second tank containing another color developing agent; a first tank. Supplying means for supplying the developing agent of No. 2 to the developing apparatus; second supplying means for supplying the developing agent of the second tank to the developing apparatus; and supplying the agent of the developing apparatus to the first tank and the second tank. Switching means for selectively supplying; color instructing means for instructing a recording color; state monitoring means for monitoring the agent supply state of the image development device; referring to the instruction color of the color instructing means and the agent supply state obtained by the state monitoring means, When the agent supply state and the indicator color are different,
A developer supply control means for collecting the developer supplied to the image developer and then instructing to supply the developer of the instruction color to the image developer; the developer of the image developer on the side of the image developer. A means for generating an electric field to be attracted to the imaging device; and a developer recovery control means for energizing the means for generating the electric field when the developing device is supplied with the developing agent. apparatus. 2. The developer recovery control means energizes the bias voltage applying means for applying a bias voltage to the developing device when the developing device is supplied with the developing agent.
The recording apparatus according to claim (1), which deenergizes a charging charger that charges the photosensitive member. 3. The recording apparatus according to claim (2), wherein the bias voltage applying means is an electrode member for applying a bias voltage for preventing background contamination of recording. 4. The recording apparatus according to claim 3, wherein the electrode member is a developing roller. 5. A recording apparatus comprising a photoconductor, means for forming an electrostatic latent image corresponding to image light on the photoconductor, a developing device for developing the electrostatic latent image into a visible image, and a recording sheet for recording the visible image. The recording device according to claim (1), wherein the recording device is an electrophotographic recording device including a transfer unit for cleaning the surface of the photosensitive member and a cleaning unit for cleaning the surface of the photosensitive member after the transfer. . 6. The cleaning means comprises a recovering agent supplying means for returning the recovering agent to the first tank.
The recording device according to the item.