JPH0695257B2 - Overflow tank level detector - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a liquid level detection device for an overflow tank, which communicates with a liquid container via an overflow pipe line.

(Prior Art) An electrophotographic copying machine that forms a multicolored visible image corresponding to an original image on a recording medium with black and other chromatic colors,
For example, as shown in Japanese Examined Patent Publication No. 54-43898, there is a type in which one selected developing solution is supplied to a common developing device for development.

In this type of copying machine, in order to remove the developing solution used for development from the surface of the photoconductor, regardless of the developing solution, the black developing solution is supplied from the black developing tank to the cleaning device, and this developing solution is used for exposure. It is configured to clean the body surface, and at the same time, is configured to collect the black developing solution supplied to the cleaning device together with the removed developing solution in the black developing tank. Therefore, the black developing tank consumes black developing. The above developer will be collected, and may overflow when used for a long period of time.

In order to avoid this kind of situation, of course, the container of the black developing tank should be enlarged, but this will inevitably lead to the enlargement of the device. At the same time, it is better to dispose it outside the main body of the copying machine so that the overflowing black developer can be stored therein.

However, in the case of such a configuration, it becomes necessary to provide a level sensor for monitoring the liquid amount also in the overflow tank, and it becomes a cost problem to make this tank a disposable type, There is a problem that the circuit configuration in the device is further complicated.

(Purpose) The present invention has been made in view of the above circumstances, and an object of the present invention is not limited to the developing tank for the color copying machine described above, but generally constitutes a part of a liquid circulation system, and Focusing on the problem that occurs in the liquid container where liquid flows in from other systems, the level of the tank that stores the liquid level that overflows from this type of container is detected by the level sensor provided in the liquid container. It is possible to provide a new device capable of reducing the cost of this type of tank and greatly simplifying the circuit configuration and the like.

(Structure) That is, in order to achieve such an object, the present invention provides a liquid container which constitutes a part of a liquid circulation system, and in which a liquid flows in from a system other than this circulation system. , A closed overflow tank that communicates with this container via an overflow pipe is also installed, and a pipe with an open upper end that reaches the detection position of the liquid level detector installed in the liquid container Is provided in the overflow tank liquid level detection device.

Therefore, the details of the present invention will be described below based on an example of the illustrated mono-color copying machine.

FIG. 3 shows the whole of a monocolor copying machine to which the apparatus of the present invention is applied.

The original placed on the contact glass plate 1 and pressed by the pressure plate 2 is illuminated by the lamp 10, and the reflected light from the original is reflected by the first mirror 11, the second mirror 12, the third mirror 13, the lens unit 14 and An image is formed on the surface of the photosensitive drum 3 via the fourth mirror 15. The photosensitive drum 3 is rotationally driven clockwise by a main motor via a power transmission mechanism (not shown). The lamp 10 and the first mirror 11 are mounted on a first carriage (not shown) and driven at a constant speed in the direction of arrow A in the figure, and the second mirror 12 and the third mirror 13 are mounted on a second carriage (not shown). It is driven in the direction of arrow A at a speed half the speed of one carriage. The surface of the photoconductor drum 3 is uniformly charged by the main charger 4, and the charged surface is exposed by the image forming unit to generate an electrostatic latent image on the surface. This electrostatic latent image is visualized by a developing solution in the developing device 5 and becomes a visible image. The visible image is further fed from the cassette 16 by the transfer roller 7 at the transfer roller 7 by the paper feed roller 17, It is transferred onto the recording paper fed via the paper guides 19, 21 and 6 by the registration roller 20 and the registration roller 22. The recording paper is separated from the photoconductor drum 3 by the separation unit 8 and then the paper guide 23
Is guided to the fixing device 24, where it is subjected to the fixing action by the heat of the heater, and then is guided by the paper guide 25 and sent out from the paper discharge roller 26 to the paper discharge tray 27. On the other hand, the surface of the photosensitive drum 3 is cleaned by the cleaning unit 9.

As described above, the urging control of the mechanical elements in various states 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 full-color copying machine. There is.

FIG. 4 shows the inside of the developing device 5. The developing device 5 has an inlet 28 to which various developing liquids and cleaning liquids are supplied and these outlets 29, and a container 160 is A first developing roller 161, a second developing roller 162, and a squeeze roller 163 are rotatably supported. Each of these rollers is a conductor, is arranged at a very small distance from the surface of the photosensitive drum 3, and is connected to a main motor (not shown) via a power transmission means. The rollers 161 and 162 are shown in the figure. The roller 163 is rotationally driven in the counterclockwise direction and in the clockwise direction. These rollers 161, 162 and 163
Rotates when the photoconductor drum 3 is rotating, and stops when the photoconductor drum 3 is stopped. Rollers 161, 1
62 and 163 have scrapers 164, 165 and 1 respectively
The free ends of 66 contact each other, and these scrapers scrape off the developer adhering to the surface of the roller,
The scrapers 164 and 165 have the function of retaining the developer or cleaning liquid flowing down from above, and wet the surfaces of the rollers 161 and 162 with the retained liquid. Laura 161
The liquid adhering to the surfaces of 162 and 162 is attracted by the charges on the surface of the photosensitive drum 3 and transferred to the photosensitive drum 3, while the roller 163 removes the excessive liquid on the surface of the drum 3.

FIG. 5 shows the internal structure of the cleaning unit 9. The container 77 is mounted on a support arm 176 which is integrated with the frame of the main body of the copying machine (not shown). The bracket 78 is pivotally attached to a shaft 83 fixed to the body frame, a blade 80 is fixed to one end of the bracket 78, and a sponge roller 79 is fixed to the other end.
Further, the shaft 83 is engaged with a plunger of a solenoid device (not shown) so that the blade 80 and the roller 79 are pressed against the drum 3 by energizing the solenoid device while the drum 3 is rotating. When the drum 3 is stopped, the solenoid 80 is deenergized to urge the return spring (not shown) to rotate the drum 3 in the clockwise direction to separate the blade 80 and the roller 79 from the drum 3, and the roller 79 to the squeezing roller 81. Is configured to release from compression.

The squeezing roller 81 is pivotally attached to the frame of the main body, and the scraper 84 contacting the roller 79 causes the sponge roller 79 to rotate.
It acts to further remove the more scraped liquid. Further, a receiving tray 82 is fixed to a shaft 82a pivotally attached to the frame of the main body, and the receiving tray 82 descends onto the roller 79 by its own weight. An inlet 40 is provided at the upper end of the container 77, in which the developer in the first tank (black developer tank) 30 is pumped.
Supplied by 38 and flows down onto a saucer 82, the free end 82 of which
Drain from b onto drum 3. Further, an outlet 41 is provided at the lower end of the container 77, and together with the developer flowing down from the free end 82b of the tray 82 between the drum 3 and the roller 79, the photosensitive drum 3
The developer removed from the above is returned to the first tank 30.

Returning to FIG. 3 again, 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 port of the cleaning liquid pump 37i are connected via respective pipes. The outlet 29 of the developing device 5 is connected to the inlet of the flow path switching valve 39, and its outlet is switched to the nozzle 44 and the first tank (black developer tank) 30. The switching valve 39 has
A two-position switching mechanism (not shown) is coupled, and the two-position switching mechanism is driven by the solenoid device 42. Then, in the state where the switching valve 39 is connected to the outlet 29 and the nozzle 44,
When the solenoid device 42 is energized for one rotation, the two-position switching mechanism drives the switching valve 39 counterclockwise in the figure to connect the outlet 29 and the first tank 30, and the outlet 29 and the first tank 30 are connected. When the solenoid device 42 is energized once in the connected state, the two-position switching mechanism drives the switching valve 39 clockwise in the figure to connect the outlet 29 and the nozzle 44. The switch 39 has a position detection switch 43
The switch 43 has a switch valve 39 at the outlet.
Closed when 29 and nozzle 44 are connected, exit 29
When the first tank 30 and the first tank 30 are connected, the switch 43 is opened.

The nozzle 44 is rotatably supported by a pulse motor 45, and the outlet of the nozzle 44 is disposed below the recovery pipe.
When located on 47r, the liquid discharged from the nozzle 44 flows into the second tank (red developer tank) 30r, and when located on the pipe 47g,
When the liquid is located in the third tank (green developer tank) 30g, on the nozzle pipe 47b, the liquid is located in the fourth tank (blue developer tank) 30b, and further on the pipe 47i, the liquid is the cleaning solution tank 30i. It is supposed to flow to. Further, the position of the nozzle 44 is detected by the position detection switch 46 (46r, 46g, 46b, 46i), the switch 46r is closed when the outlet of the nozzle 44 is on the pipe 47r, and the switch is output when the outlet is on the pipe 47g.
46g is closed, the switch 46b is closed when the outlet is on the pipe 47b, and the switch 46i is closed when the outlet of the nozzle 44 is on the pipe 47i. And both switches are open when the nozzle 44 is not in the switch position.

From the pump 38 to the inlet 40 of the cleaning unit 9
The black developer in the tank 30 is supplied, and 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,
3rd tank (green developer tank) 30g and 4th tank (blue developer tank) 3
0b includes a black developer container 31, a red developer container 31r, and a red developer container 31r.
The green developer container 31g, the blue developer container 31b, and the diluent containers 32, 32r, 32g, and 32b are attached.
Solenoid devices 33r, 33g and 33b are connected to the developer containers 31, 31r, 31g and 31b via links, and when the solenoid device 30 is biased, the mouth of the developer container 31 is opened. The developer in it flows down. Diluent container 3
2, 32r, 32g and 32b are tank 30, through the nozzle of the base
It is supported at a constant height by each support plate in 30r, 30g, and 30b, and when the liquid level in the tank drops when the mouth provided at the bottom of the container is open in the tank, the diluting liquid is introduced from this mouth. It has a kind of chicken feed mechanism that flows through. Only the cleaning liquid container 32i is attached to the cleaning liquid tank 30i, and this container 32i is also supported at one height by the support plate in the tank 30i through the nozzle of the mouthpiece, and the cleaning liquid level in the tank 30i. When the temperature decreases, the cleaning liquid flows out into the tank 39i through the opening provided at the lower end of the container.

For the first tank 30, the second tank 30r, the third tank 30g, the fourth tank 30b, and the cleaning liquid tank 30i, the liquid level inside the tank rises,
Upper limit position detection switch 34, 34r, 34g, 34b for detecting the float linked to the descent and the vertical position of the float
And 34i, and lower limit position detection switches 35, 35r, 35
g, 35b and 35i.

A part of the liquid discharged from the first pump unit 37 is returned to the first tank 30 via the first concentration detection unit 36, and the developer is returned to the second tank (red developer tank) 30r. The second concentration detecting unit 36r is provided in the pipe 47r, the third concentration detecting unit 36g is provided in the pipe 47g for returning the developing solution to the third tank (green developer tank) 30g, and further, the fourth tank (blue developing solution tank). ) A fourth concentration detecting unit 36b is connected to the pipe 47b for returning the developing solution to 30b. Each of these detection units 36, 36r, 36g
And 36b are flow path means for flowing the developing solution in a thin film shape, and lamps facing each other with the thin film strip developing solution therebetween (see FIG. 7).
36L) and a photoelectric converter (36S in FIG. 7) are main components, and the electric circuit configuration is shown in FIG.

By the way, the above-mentioned first tank (black developer tank) 30 for containing the black developer is provided with an overflow tank 90 for containing the developer which has overflowed from the first tank 30. The tank 90 is detachably disposed inside the base, which supports the main body, separately from the copying machine main body, together with the second tank 30r, the third tank 30g, the fourth tank 30b and the cleaning liquid tank 30i.

FIG. 1 shows the relationship between the overflow tank 90 and the first tank 30. On the side surface of the first tank 30, the overflow tank is located from an intermediate point c between the upper limit level a and the lower limit level b of the liquid level. The drain hose 91 extends toward the inside of 90. Further, the overflow tank 90 is provided with an air bleeding hose 92 having a height exceeding the upper limit level a of the liquid level in the first tank 30,
Together with the drainage hose 91, the lower end of the overflow tank 90 is located at the level d position in the overflow tank 90.
It is supported by a common stopper 94 that seals the mouth portion 93 of 90, and when the stopper 94 is removed by this, the upper limit level a of the first tank 30
Even if the developing solution reaches the overflow tank 90, it does not overflow.

The air bleeding hose 92 does not need to be directly raised from the overflow tank 90, and the T-shaped elbow 95 protruding from the side wall of the first tank 30 as shown in FIG.
May be connected to the upper connection end of the
When 30 is configured as a closed tank, the upper end of the air bleeding hose 92 may be connected to the inside from the upper portion of the first tank 30 as shown in FIG. In addition, in this embodiment, the position detection switch 34 arranged in the first tank 30 is used.
As such, a non-contact type detection switch including a float magnet and a magnetic sensor is used.

While the photosensitive drum 3 is rotating, the rollers 161, 162 and 163 of the developing device 5 are also rotating, the bracket 78 of the cleaning unit 9 is placed at the position shown in FIG. The roller 79 is in pressure contact with the photosensitive drum 3. Further, the black developing solution in which the pump 38 is energized is supplied to the cleaning unit 9.

In the black recording setting state, the switching valve 39 connects 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.

Also, in the red recording setting state, the switching valve 39 is
Connect 44, the nozzle 44 is positioned on the pipe 47r,
The pump 37r supplies the red developer to the developing device 5. Similarly, in the green recording setting state, the switching valve 39 connects the outlet 29 to the nozzle 44, the nozzle 33 is positioned on the pipe 47g, and the pump 37g
Supplies the green developing solution to the developing device 5. Similarly, in the blue recording setting state, the switching valve 39 connects the outlet 29 to the nozzle 44,
44 is positioned on the pipe 47b, the pump 37b supplies the blue developer to the developing device 5, and in the blue recording setting state, the switching valve 39 connects the outlet 29 and the nozzle 44, and the nozzle 44 is the pipe.
Positioned on 47b, pump 37b supplies blue developer to developer 5.

When changing from the black recording setting state to the red recording setting state, the first pump 37 is de-energized, and the switching valve 39 is turned off after the liquid drain time T ₁ of the developing solution.
Is switched to the nozzle 44 side, and at the same time, the nozzle 44 is connected to the pipe 46.
positioned on i pump 37i for cleaning time t ₂
Is activated. t ₂ is the pump 37i is de-energized after the pump 37r is biased nozzle 44 from the de-energization after liquid switching time T ₁ of the cleaning liquid is positioned on the pipe 47r.

Similarly, switching from the black recording setting state to the green recording setting state or the blue recording setting state is also performed, and switching from one of the red recording setting state, the green recording setting state and the blue recording setting state to the other is also performed. The same operation is performed, but in this case, the switching valve 39 is not switched.

When switching from the red recording setting state, green recording setting state or blue recording setting state to the 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 frequently used black recording setting state, the switching valve 39 is switched to the first tank 30 side at the same time as the pump 37r, 37g or 37b is de-energized. The cleaning liquid is not supplied to the developing device 5, and thus 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. 6 shows a part of the operation board 48 provided in the copying machine. The respective elements will be described. In the figure, reference numeral 76 is a standby support switch with a built-in light emitting element, and a power switch (not shown) is turned on. When the switch 76 is turned on in the above state and the light emitting element is in the non-illuminated state, the light emitting element is turned on, the copying machine is in the standby state, and the fixing heater is energized at a low temperature. Further, if 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 support waiting state, and the fixing heater is energized to a high temperature.

Reference numeral 49 denotes a copy start switch having a red light emitting element and a green light emitting element built-in. The green light emitting element is lit when the copying machine is ready for copying and when the copying machine is ready for copying. The cycle has begun,
At the same time, the red light emitting element lights up, and when the set number of copies have been completed and the red light emitting element goes out, the green light emitting element turns on, and 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.

"Auto Feed" is an auto-feed instruction switch with a built-in light-emitting element. When this switch is turned on, the light-emitting element lights up, and the copying machine automatically feeds the originals onto the contact glass 1 by the attached feeder. When the switch is turned on while the light emitting element is lit, the light emitting element is turned off, and the copying machine enters the normal mode setting in which the original is manually placed on the contact glass 1.

"Porwer On" is a power indicator light that lights up when a power switch (not shown) is on, and goes off when it is off.

“Interrupt / Resume” is an interrupt instruction switch with a built-in light emitting element. When this switch is turned on when the light emitting element is off, the setting status data of the operation board 48 and the copy data of the copying machine (number of copied sheets, etc.) are displayed. It is saved in the memory and waits for the copy instruction for the set number of sheets 1.
The operation board 48 can be changed to any setting to instruct copying (interrupt copy setting status). Also, when this switch is turned on when the light emitting element is on, 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 reset.

Reference numeral 51 is a three-digit character display, which displays the number of copies to be set before the start of copying and displays the number of copies completed after the start of copying, but is also used at the same time as an error display.

55 is a light-emitting element for displaying a developer shortage, a lower limit detection switch
Lights when 35, 35r, 35g or 35b is closed.

Reference numeral 56 is a light-emitting element for indicating insufficient cleaning liquid, which lights up when the lower limit switch 35i is closed.

Reference numeral 57 is a light emitting element for displaying a check instruction, which is lit when any one of the upper and lower limit switches is closed, or when there is an abnormality such as paper trouble or mechanical trouble.

Reference numerals 53, 53r, 53g, and 53b are color setting indicators, and when the power switch is turned on, the black setting indicator 53 lights up to enter the black recording mode.

50 is a color instruction switch, for example, when the black setting indicator 53 is lit, if this switch 50 is turned on, the black setting indicator 53 turns off and the blue setting indicator 53b turns on, and the blue recording mode is set. Every time you press this switch 50, green,
The setting indicators 53g, 53r, 53 are turned on in the order of red and black, and the recording mode of the corresponding color is set.

Reference numeral 54 denotes a trouble indicator light of the first tank 30, which lights up when the upper and lower limit position detection switches 34 or 35 are closed or the container 31 is empty.

54r, 54g, 54b and 54i are trouble indicator lights of the second, third and fourth cleaning liquid tanks 30r, 30g, 54b and 54i.
Lower limit position detection switch 34r, 34g, 34b, 34i or 35r, 35
When g, 35b, 35i are closed, or containers 31r, 31g, 31b,
Lights when 35i is empty.

The shaded area around the indicator lamp 54 indicates the illumination area of the paper trouble indicator lamp, and the operation board 48 has a light emitting element SADF that lights when the semi-auto feeder is mounted on the copying machine. Light emitting element ADF that lights when the auto feeder is installed in the copying machine, light emitting element that lights up when the feeder is not installed, and a numeric keypad switch for inputting the number of copies and other information "0"
The switch and display element such as "9", ten-key input and "clear" switch for inputting the number of copies set and "recall" instruction switch for reading operation board setting data stored in the previous memory are installed.

FIG. 7 shows an electric system for energizing each mechanical element of the copying machine. Switches 61 such as an input switch, a state detection switch, and a state setting switch of each part of the copying machine are buffer amplifiers 59, 60. To the microprocessor 58 and also to the driver 68. A drum synchronization pulse generator 62 is connected to the interrupt input port INT of the microprocessor 58, and the pulse generator 62 detects a photo sensor 62S that detects a light-projecting slit of a rotating plate (not shown) coupled to the light-emitting drum 3. The sensor 62S detects the projection slit each time the drum 3 rotates by a minute angle.
Apply pulse to interrupt input port INT. The fuser unit 24 is connected to the A / D conversion input port AD1 of the microprocessor 58.
When the temperature detection circuit 63 that detects the fixing unit temperature is connected and the thermistor 63S generates a voltage corresponding to the fixing unit temperature,
This is applied to AD1. To the A / D conversion input ports AD2, AD3, AD4, and AD5 of the microprocessor 58, the developer concentration detection units 36, 36r, 36g, and 36b are connected, respectively, and the photoelectric conversion element 36S is connected to the first pump 37. AD is generated when a voltage corresponding to the concentration of the drawn black developer is generated.
2, 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 the same as that 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. , The microprocessor 58 also has an address bus,
ROM6 via control bus and data bus
7, RAM 66, and input / output port buffer elements 64 and 65 are connected, and drivers 68 to 71 and drivers 72 to 75 are connected to these input / output port buffer elements and 65, respectively.

The driver 68 sequentially supplies a switch state read signal to each of the Y scan lines of the switch matrix 61, and sequentially supplies 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, a signal indicating the opening or closing of each switch is given to the microprocessor 58 via the buffers 59 and 60, and the microprocessor 58 sends the display element energizing signal via the buffers 69 and 70, if necessary. This is applied to each of the X lines of the matrix 76, and 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 simultaneously applied are turned on. The driver 71 is connected with a mechanism drive element (not shown) (main motor, clutch, etc.), and the driver 72 is connected with an electric element of the image forming system (lamp 10, charger 4, 7, etc.)
Electrical elements (clutch, motor, etc.) (not shown) of the paper transport system are connected to 73, and electrical elements of the developer supply system, namely pumps 38, 37, 37r, 37g, 37b, 37i, are connected to the driver 74.
Solenoid devices 42, 33r, 33g, 33b and pulse motor 4
5 is connected to the driver 75, and the driver 75 is connected to a device to be mounted on the copying machine, for example, a connector for connecting electric elements such as a feeder and 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.

The control operation of a microprocessor CPU in a copying machine is 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.

8a to 8f show the control operation of the microprocessor 58 mainly regarding the developer supply control.

First, referring to FIG. 3, 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: hereinafter in parentheses). Omit the word "step"). In this initialization 1, first, each element of the copying machine is set to the inoperative state, and the microprocessor is set.
The internal counters, timers, registers, etc. of 58 are initialized, and the state tracking registers, etc. assigned to the RAM 66 are also initialized. Then, the standard state of the operation board 48 is set, and the data indicating the set state is set in the memory. In the standard state, the number of copy settings is 1 and the color is black (indicator 53
Lighting), the indicator lamp 53 is turned on, the black flag is set, and 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 urging the heater of the fixing unit 24 to activate the high temperature heat generation (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, abnormal processing (5)
And wait 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 (3 rotations of the drum), and the pump 38 is turned on (black developer is supplied to the cleaning unit 77). Yes (7a). In the developing device 5, the rollers 161 to 163 are rotationally driven in association with the main motor urging and the pump urging, and the main charger 4
Is activated. Note that this charger bias is applied to the roller 161.
The toner in the developer on the surface of ~ 163 is sucked into the drum 3,
This is because it is collected by the unit 9. Bracket 78 as well
Is driven to move to the position shown in FIG. 5, whereby the blade 80 and the sponge roller 79 are pressed against the drum 3 (7a). Next, the microprocessor 58 refers to whether the time T is equal to or longer than the liquid draining time T ₁ , and if it is less than T ₁ , refers to the fixing unit temperature (63S output) of the fixing unit 24 (7b). ). Here, when the time T is less than T ₁ and the fixing unit temperature is less than the set fixing temperature, the process waits and the time T
Wait until it becomes T ₁ or higher or the fixing part temperature becomes higher than the set fixing temperature (7b). When the time T becomes T ₁ or more, the developing device 5
When the fixing section temperature exceeds the set fixing temperature and copying is possible, the microprocessor 58 refers to the state of the switch 43 for cleaning the developing device 5 (8). When it is not closed (the outlet 29 of the developing device 5 is connected to the first tank 30), the solenoid device 42 is energized during t ₁ (9). As a result, the switching valve 39 connects the outlet 29 and the nozzle 44, and the switch 43 is closed. switch
If 43 is or is closed, then refer to the state of switch 46i (10). Since the nozzle 44 is not on the pipe 47i unless the switch 46i is closed, the other switches 46r, 46g
And 46b, the pulse motor 45 is biased in the reverse direction to position the nozzle 44 on the pipe 47i (11). Position it in this way, or make the nozzle 44 pipe 47i.
When it is on the upper side, the pump 37i is energized for t ₂ to move the developing device 5 to t.
Between ₂ cleaning (2). During this t ₂ , the cleaning liquid in the tank 30i is supplied to the developing device 5 and is collected in the tank 30i. When cleaning is completed, counting of time T is started, and the cleaning completed flag is set (1
3). 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.

After cleaning (12), the microprocessor
58 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. Wait 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 end copy. The end cycle is started when the final copy is finished, and then te
The time limit timer te (program timer) is set, 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-out is reached (end cycle end), the end cycle is stopped (1
8). 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 becomes possible (12). When the count value of the time T reaches t ₃ after the copy setting is possible (step 12 and the copy of the set number of copies is completed) (17), the fixing heater is switched to the preheat activation (low temperature heat activation), and the standby switch
Turn on the light emitting elements of 76 (19), stop the main motor,
Stop the pump 38 and deactivate the main charger 4 (2
0), waiting for the standby switch 76 to turn on (21: standby state). When the standby switch 76 is turned on even when not in the standby state, this is detected in step 14, and the process proceeds from step 25 to step 19 to enter the standby state. When the standby switch 76 is turned on in the standby state (21), the main motor is activated and the main charger is activated, as in step 7a. Further, the pump 38 is energized (22), the fixing heater is energized with high heat (23) as in step 2, and the operation board reading (14) is proceeded 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 (27), the reading associated with the operated key is performed ( 28). A typical example of this reading is the setting of the number of copies according to the ten-key input.

When the color instruction switch 50 is operated, the microprocessor 58 executes the recording color instruction reading and the overflow processing of the first tank 30 in steps 26 to 8b in FIG. 8a. Explaining these, if it is assumed 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 a black flag in the register of the microprocessor 58 or the register of the RAM 66. Is set. Therefore, the microprocessor 58
Goes to step 29-31-33-35, clears the black flag in step 35 to turn off the light emitting element 53, sets the blue flag to turn on the light emitting element 53b, and perform one switch operation twice or more. Wait for t ₄ to elapse without reading (3
6), the overflow treatment of the first tank (black developer tank) 30 in steps 37-41 is performed, and the overflow tank 90 (FIG. 1) communicating with the first tank 30 through the drain pipe 91 is full,
The first tank trouble indicator lamp 54 and the operator check 57 are left as they are, except for an abnormal case where the developer reaches the level a of the upper limit switch 34 through the air bleeding pipe 92, and the operation board reading (14) in FIG. 8a (14). Return to. When the color indicating switch 50 is operated while the blue flag is set, the microprocessor 58 causes the steps 58-31-33-34.
The blue flag is cleared in step 34 and the light emitting element 53b
Off and the light emitting element 53g lit by setting the green flag, waiting time of t ₄ (36) first step 37-41
After the overflow processing of the tank 30, the process returns to the operation board reading (14) in FIG. 8a. When the color instruction switch 50 is operated while the green flag is set, the microprocessor 58
Proceed to step 29-31-32, clear the green flag in step 32 to turn off the light emitting element 53g, set the red flag to turn on the light emitting element 53r, and wait for t ₄ hours (36) step 3
After the overflow processing of the first tank 30 of 7 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 causes the steps 29-30
Then, in step 30, the red flag is cleared and the light emitting element 53r
Off and set the black flag turns on the light emitting element 53, t ₄
(36) Wait for the passage of time (36), and after the overflow processing of the first tank 30 in steps 37 to 41, read the operation board (1
Return to 4). 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 a time interval of approximately t ₄ . Therefore, by continuously turning on and / or intermittently turning on the color instruction switch 50, black,
Either blue, green or red can be specified.

When the recording color instruction reading (29 to 36) is passed and the overflow processing (37 to 41) of the first tank 30 is proceeded to, the microcomputer 58 first refers to the state of the switch 34 (37).
As described above, during the rotation of the drum 3, the pump 38 sends the black developing solution to the cleaning unit 24 and the discharged liquid of the unit 24 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 24, and these are collected from the developing device 5 and the unit 24 into 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, the second tank 30r
The red developing solution is supplied to the developing device 5 from the developer and the discharged liquid is collected in the second tank, but the red developing solution attached to the drum 3 and collected by the cleaning unit 24 is collected in the first tank 30. . Therefore, when the liquid amount in the first tank 30 increases and reaches a certain level c (FIG. 1), the developer flows into the overflow tank 90 through the drain pipe 91.
The internal liquid level also exceeds the level d and the liquid level in the first tank 30 reaches the upper limit a together with the developer having entered the air bleeding pipe 92, and the switch 34 is closed. In this state, further blue, green or If red recording is performed, the developer may overflow in the first tank 30. Overflow processing of the first tank 30 (37 to 41 are control steps for avoiding such overflow in advance. That is, when the switch 34 is closed (the liquid amount of the first tank 30 is equal to or more than the upper limit), (37 ), There is a risk of overflow, and even if black recording is performed in this state, the developing solution is not supplied from the black developing solution container 31 and the recorded image density gradually decreases, so to inform the operator of this abnormal situation, First tank trouble indicator light 54
Then, the operator check indicator light 57 is turned on (39) and the presence or absence of the black flag is referred to (40). 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). Since it is a recording instruction, all the red, green and blue flags are cleared, the black flag is set, the red, green and blue indicator lights 53b, 53g and 53r are turned off and the black indicator 53 is turned on (41 ), And proceed to operation board reading (14).

In this case, at the same time when the operator check 57 is turned on, the type of the abnormal mode is displayed as a symbol on the three-digit character display 51, and the operator refers to the card corresponding to this display to reduce the developer in the first tank 30. It is also possible to manually perform the color recording operation by performing the above-mentioned procedure.

When the operator replaces the overflow tank 90 or discharges the developer in the tank 90 to open the switch 34 and operates the switch 50 in response to the lighting of the indicator lights 55 and 57, the microprocessor 58 causes the step 58 15-25-
26-reading the recording color instruction in FIG. 8b-37-38, and turn off the indicator lamps 54, 57. If the switch 34 remains closed, the indicator lights 54 and 57 are turned on and the recording color is set to black (black flag is set).

Upon detection of the closing of the start switch 49 by the operation board reading (14 in FIG. 8a), the microprocessor 58 executes the step 15
After -25-26-27, proceed to step 42 in FIG. 8c. 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 under the condition that the operation board of the copying machine is read.

By the way, if the fixing unit temperature of the fixing unit 24 is K or higher,
Proceed from step 42 to step 43 to see if there is a black flag. 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. switch
If 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. 8d. 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
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 (46). Then, in order to wait for the black developer from the first tank 30 to reach the rollers 161-163 of the developing device 5, the time t ₅
(47), and when t ₅ has elapsed, proceed to developer adjustment shown in FIG. 8d. In this black development set (black recording state setting), the developer that was previously in the developing device 5 flows down (drains).
It should be noted that there is no waiting for T _{1 to} elapse, a time of t ₂ for supplying the cleaning liquid to the developing device 5, and a T ₁ having the cleaning liquid flowing down (draining) 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 also closed, the switching valve 49 is located on the nozzle 44 side and the nozzle 44 is closed.
Is located on the pipe 47b and is in a state of supplying the drainage of the developing device 5 to the fourth tank (blue developer tank) 30b. This is the copying operation immediately before this is the blue copying process. This means that draining and cleaning of the developing device 5 are unnecessary, and therefore the process proceeds directly to the developing liquid adjustment shown in FIG. 8d.
When the switch 43 is not closed, it means that the copy operation just before this was the black copy process, and therefore T ₁ elapsed waiting time (50:
Details are shown in Figure 8f. After that, the solenoid device 42 is energized during t ₁ to position the switching valve 49 on the nozzle 44 side (51), and the cleaned flag is referred to (5).
Four). The presence of the cleaned flag indicates that the copying machine is currently in the state where the cleaning of the developing device 5 is completed. Therefore, when there is a cleaned flag, the nozzle 44 is positioned on the pipe 47b (59) and the pump 37b is urged (60), so that the blue developer is applied to the rollers 161 to 163 of the developing device 5.
Wait for time t ₅ to wait for (61),
When t ₅ elapses, the process proceeds to developer adjustment shown in FIG. 8d. Step 54
When there is no cleaning completed flag in the developing device 5, the developing liquid previously contained in the developing device 5 is black, green or red, and the blue developing liquid is about to be supplied this time, so cleaning is required. Cleaning 5 (5
Five). This cleaning (55) has the same contents as the cleaning (11 to 13) of the developing device shown in FIG. 8a. In addition,
Cleaning the developing unit (55), as in Step 13.
Note that the counting of time T has started. Next, the cleaned flag is set (56), the time T counting is started (57), and the elapse of T ₁ is waited (58).
The contents of "Wait for T ₁ " (50, 53, 58) are shown in Fig. 8f.

Here, referring to FIG. 8f, the contents of “waiting for the passage of T ₁ ” will be explained. First, since the counting of the time T has already started, it is judged whether or not this time T is T _1. Do (10
2) If not, it waits until it becomes T ₁ , but while it waits, the operation board is read (103), and if there is an input from the operation board, proceed to step 25 in Fig. 8a and enter the input. Perform appropriate processing. Therefore, the switch 50 may be operated to change the recording color designation while waiting for the elapse of T ₁ . When the designation of the recording color is changed, if the cleaning flag is present, it means that the developing device 5 is in a clean state in which cleaning is completed.
If there is no cleaned flag, it means that cleaning is required. Note that this "wait for T ₁ " (50, 53 and 58) is positioned before the positioning of the nozzle 44 (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: 8f
Even when the operation of switch 50 is detected by reading the operation board in the figure) and the recording color (color flag) is changed, the developer is discharged to the position before the previous color setting (color flag) where copying was not executed. Since there is the nozzle 44, no error occurs in the positioning control of the nozzle 44. If there is a cleaned flag when the recording color (color flag) is changed, the cleaning process (55) in steps 55 to 58 and the waiting for the cleaning liquid draining time T ₁ (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 step 60 “37b” is read as “37r”.

When the developing set is executed as described above, the pump 37 (46), 37b (60), 37g (63) or 37r (64) is energized by this, so it will be developed when the recording color is changed next time. Since it is necessary to clean the device 5 (however, it is unnecessary to change from blue, green or red to black), the cleared flag is cleared (65a) and the process proceeds 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). If so, the pump 37b is currently energized to supply the blue developing solution from the fourth tank (blue developing solution tank) 30b to the developing device 5, and the drainage of the developing device 5 passes through the concentration detection unit 36b. Returned to 4 tank 30b. Therefore, in this case, blue developer adjustment (66 to 81) is executed. That is, the voltage of the photoelectric conversion element of the density detection unit 36b (FIG. 7) is A / D converted and compared with the set value (66). When the density indicated by the conversion data is equal to or higher than the set value, the density of the developing solution is appropriate, so the number of times n of supplying the developing solution is set to 0 (clear) (73a) and the switch 35b is set.
Refer to the state of (73b). If switch 35b is not closed,
Since the developer level in the fourth tank 30b is appropriate, the trouble indicator lamps 54b, 55 and 57 are turned off (74), the copy number change flag is cleared (75), and the routine proceeds to step 81. 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 (78). If the number of remaining copies is less than 99, it is left as it is, and if the number of remaining copies exceeds 99, the number of remaining copies is set to 99 (79) and the copy setting number change flag is set. Set (80). That is, the number of sheets that can be copied thereafter is set to within 99. If the copy set number change flag is set when the indicator lamp is turned on in step 76, the copy set number has not been 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 developer 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 76-80. When the switch 34b is not closed, there is no risk of overflow, so refer to the value of the developer supply number n (69). If it is less than 5,
Energize solenoid device 33b during t ₆ (70). As a result, the container 31b is opened during t ₆ and the developer in the container 31b is stored in the fourth tank.
Supplied to 30b. And the supplied developer is the fourth tank 30b.
The developer is mixed with the developing solution of (3), and it goes to the developing device 5 and waits for a sufficient time t _{7 to} reach the density detecting unit 36b (7
2) Change the value of the developer supply circuit n to a number one larger (7
2) Perform concentration detection (66). If the concentration is still low in this concentration detection (66), the fourth tank 40b is again removed from the container 31b.
Supply developer to (69-72). When the density becomes higher than the set value, the process proceeds from step 67 to step 73a,
Although the developing solution supply flow is exited, if the concentration does not reach the set value or more even after the developing solution is supplied five times (because there is no developing solution in the container 31b), the process proceeds to changing the set number of copies in steps 76-80.

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 (8
1). If 34g, 34r, or 34i is closed, the nozzle 44 is positioned differently, and the developer sent to the developing device 5 in the fourth tank (blue developer tank) 30b is transferred from the developing device 5 to another tank.
Since there is a possibility that it has been sent to 30r, 30g, or 30i, the process proceeds to the above 82. If the switches 34g, 34r and 34i are all open, the positioning of the nozzle 44 is considered correct and then the state of the switch 34 is referenced (83). When the switch 34 is closed, during the blue copy, a part of the blue developing solution transferred from the developing device 5 to the drum is collected by the cleaning unit 9 and goes to the first tank (black developing solution tank) 30, where The amount of the developer in the tank 30 may increase, and the first tank 30 may overflow.
Therefore, when the switch 34 is closed, the steps shown in FIG. 8b are performed.
Proceed to the color setting change already described in 39-41. switch
When 34 is not closed, the process proceeds to the copy control shown in Fig. 8e.

In the above, the blue developer adjustment when the blue flag is present has been described. Below, green developer adjustment when there are green flag, red flag, and black flag (84, 85) red developer adjustment (86, 8
7), black developer adjustment (88) is the same as blue developer adjustment. However, in step 66, "36b" is "36g", "36g"
r ”,“ 36 ”and“ 34b ”in step 68 are“ 34g ”and“ 34
r ”,“ 34 ”and“ 54b ”in steps 74 and 76 are“ 54g ”,
"54r", "54" and "33b" in step 70 is "33g",
"33r", "33" and "35b" in step 73b is "35g",
"35r", "35" and also "34g" in step 81 is "34
Read "b" and "34r" (add "34b" to step 81 in black developer adjustment (88)).

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 recovered liquid of the unit 41 is also returned to the first tank 30. The developer amount 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.
Therefore, in the black developer adjustment, when 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. 8e.

The copy control will be described with reference to FIG. 8e. 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. 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 in the save memory, and
The processing shown in the figure 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 is not more than the set number, copy processing (90) is required again, so read the state of each part of the copying machine (95) and judge whether or not the copy processing can be continued (96). If it cannot be continued, the process proceeds to error processing (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. Therefore, a timer for the te time period is set (99), the pumps 37, 37r, 37g and 37b for supplying the developing solution are deactivated (100), and the counting of the time T is started (101). Then, the process returns to the operation board reading (14) in FIG. 8a. By deactivating the pumps 37, 37r, 37g, 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 30,
Run down to 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. Also,
Indicates the elapsed time from the end of copying.

Read the operation board after finishing copying as above (14)
Return to step 14-15-16-17-14, wait for input on the operation board 48, wait for end cycle (timer te time out), and time t ₃ wait for the passage of the (still a 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. When there is no input on the operation board 48 and te elapses, the end cycle is stopped (18). When the end cycle is stopped, the rotation of the drum 2 is stopped, other mechanical parts are stopped, the pump 38 is deenergized, and the main charger 4 is deenergized. Then, when t ₃ elapses, the standby state is set (19, 20) and then the standby switch 76 is waited for being turned on (21). When the standby switch 76 is turned on, the main motor is rotated to energize the pump 38, energize the main charger 4 (22), energize the fixing heater with high heat (23), and read the operation board (14 ).

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

(1) Black recording 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. In this type of copier,
It is estimated that the black record copy has the highest probability. Therefore, the recording color in the standard copy conditions is black. However, there is a possibility that the establishment of another color may be instructed by the subsequent operation board input, and if the black developing solution is started to be supplied to the developing device 5, the black developing solution supply 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 in the memory, the developing device 5
The developer is not supplied to.

(2) Standby immediately after the power is turned on.

When the power is turned on, the counting of the time T is started (2) and the time T becomes T ₁ or the fixing unit 24
Wait until the fixing part temperature 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. The operation manual and other instructions explain that the power of the copying machine should be 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 was turned off. Because
When the power is turned on again, it is not necessary to set the drain 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 T ₁ draining time is set uniformly after the power is turned on. When the power is turned on when the fixing unit 24 is at room temperature, the time required for the fixing unit temperature to rise 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 the sand cycle after the end of the previous copy, and then the power is turned on again immediately (the probability of turning on the power 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. When the power is turned on when the fixing unit 24 is at room temperature (eg, the first power-on in the morning)
In this stage, the fixing unit temperature has not risen to the set temperature yet. 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 on 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 urging 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.

When the operation of the color instruction switch is read by reading the operation board (14, 103), the recording color is set correspondingly. (29
~ 41). In this recording color setting, if the developer level in the first tank (black developer tank) 30 is equal to or higher than the upper limit, recording colors other than black are not set and only black is set. this is,
This is to prevent overflow of the developer in the first tank 30.

(6) When the operation of the start switch 49 is read on the operation board reading (14, 103), the development set (42 to 64: to the developing device 5) is provided on condition that each part of the copying machine other than the developing system is in the copying enabled state. Supply the developer) and then adjust the developer (65
After performing steps b to 83), the process proceeds 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. If the two do not match, (7-2A) If the color of the developer supply setting required this time is red, green, or blue, (7-2A-1) wait for the drain time T ₁ of the previously used developer to elapse ( 50, 53), then cleaning is performed (55), and then the cleaning liquid drain time T ₁ 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 (50, 53) and the execution of cleaning (55) of the last used developing solution draining time T ₁ are omitted, and the cleaning solution draining time T ₁ Wait for progress (58).

(7-2A-3) While waiting for the elapse of the drainage time T ₁ , the operation board is read (103), and if there is an input, the operation proceeds 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 cleaning completed flag is cleared when the developer supply pump 37, 37r, 37g or 37b is energized (65
a).

(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,
If it is green or blue and the developer level in the first tank (black developer tank) 30 is above the upper limit (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 during one copy cycle, and if there is an input, it is stored in the memory. After the completion of one copy cycle, if the recording color instruction is changed by referring to the memory (92), the end cycle is set and the operation board reading (14) is returned to.

(12) When copying is completed, a timer is set to determine the end cycle end (99), and the developing device 5 is also used for counting the remaining (unused) time after completion of copying.
To monitor the outflow (drainage) of the developing solution at time T
Start counting (101). The developing solution supply system to the developing device 5 and the developing solution recovery system from the developing device 5 are not reset (initialized), and are left as they are. This is because there is a high probability that the next copy of the same color will be instructed, 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., thus preventing such waste. This is because

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 (21-23).
Change the recording color [from black to red, green or blue, or red, green or blue] when the switch 76 is operated to proceed to the operation board reading (14) before or during the standby state. Change the recorded color from any other color (except black)], refer to the time T count value started at the end of the above copy, and it must be T ₁ or more (50,
Cleaning starts at (53) (54, 55). Therefore, the counting start of the time T after the end of copying (101) has a shorter waiting time than the case of newly setting the liquid drain waiting time when the recording color is changed thereafter.

(13) The operation board reading (14, 103) is not executed during the cleaning (12, 55), and the operation board reading (103) is executed before or after the liquid drain standby (50, 53, 58). . This is because the cleaning time t ₂ is relatively short (for example, t ₂ is approximately 5 seconds), so it does not take a long time to wait for this to end, and after cleaning, any recording color can be set. This is because it is rational that the cleaning is completely finished when the cleaning is started. Also, the liquid-off waiting time 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 read the operation board (103) and temporarily input the operation board. Therefore, even if the process is performed accordingly, it is sufficient to continue counting the time T at that time, and the continuity of the liquid drain standby is 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 activated, the cleaned flag is cleared (65a). Then switch the recording color (red,
If there is a cleaned flag in switching to a different color (excluding switching from green or blue to black), the waiting for draining and cleaning of the pre-development liquid is omitted, and only the standby for draining the cleaning liquid is performed to wait for a new developer. Start supply. This is effective in shortening the waiting time. In particular, when the recording color designation is changed by reading the operation board (103) in the cleaning liquid drain waiting (58), the waiting time until the start of copying is changed in the changed color development set (48 to 65a). Shortened.

Incidentally, in the apparatus described above, because does not have a standby power to back up the memory when the power switch off, and the post-cleaning when the power is turned on by taking the once liquid switching time T _1, the developing device so as to initially set ing. In the case of a counter that counts time T with a standby power supply, a microprocessor, or one that backs up a microprocessor and RAM, the above steps 7b to 13 are omitted to shorten the time from power-on to copy start. To Even in this case, when the power switch is turned off for a long period of time, automatic cleaning control for performing cleaning once after a predetermined long time after turning off the power switch is included. According to this, the solidification of the developing solution on the roller or the like in the developing device 5 is prevented. Further, as described above, the standby power supply is provided to hold the required data even when the power switch is off.
Three or all of the position detection switches 46 of the nozzle 44 may be omitted. In that case, when three are omitted, for example, only one 46i is left and used for home position detection. When omitting all four, position the nozzle 44 on a specific one of the pipes 47 (for example, 47i) when assembling the device, set the nozzle position data in the memory backed up by the standby power supply, and then use the pulse motor. 45
Position tracking is performed to update the nozzle position data for each step of forward and reverse. The switch 43 can be omitted by using the same control for tracking the position of the switching valve 39.

Although the copying machine described with reference to the drawings is a single color copying machine, it is provided with a paper conveying mechanism for selectively guiding the paper from the exit of the fixing device 24 to the entrance of the registration roller 22, and the photoconductor drum 3 and The present invention can be applied to a full-color copying machine in which a filter unit composed of a plurality of filter plates is arranged between the mirrors 15 and is superposed. In this case, when full color is designated, one sheet of recording paper is returned from the fixing device 24 to the registration roller 22 in a required order, for example, a copy of cyan C, magenta M, and yellow Y in a predetermined order. Moreover, the steps are sequentially performed while switching the filter plate in the exposure optical path of the filter unit. As described above, the present invention can be directly applied to a full-color copying machine.

Further, although the above description relates to a wet developing type color copying machine, the present invention can be similarly applied to a dry developing type color copying machine. In the case of a dry development type color copying machine, the cleaning agent is a powder that adsorbs the toner, or a solvent that can dissolve or disperse the toner.

The present invention can also be similarly applied to an ink jet printer and other recording devices of the type in which recording media are applied to opposite surfaces. For example, a conventional color ink jet printer is usually provided with three ink jet heads, and inks such as magenta, cyan, and yellow are individually supplied to them, but according to the present invention, one ink jet head is provided. Supply each color ink. Ink or cleaning liquid is selectively supplied to the ink jet head from each color ink tank or cleaning liquid tank, captured by a gutter and returned to the ink tank or cleaning liquid tank via a switching valve or the like.

(Effect) As described above, according to the present invention, a part of a liquid circulation system such as a developing tank of a color copying machine is formed, and an overflow tank is additionally provided in a liquid storage container into which liquid flows from other systems. Therefore, by disposing this tank in an arbitrary space, it is possible to greatly increase the capacity of the liquid container without increasing the size of the device, and to separate the overflow tank from the liquid container for processing. This makes it possible to eliminate the overflow condition of the container without affecting the liquid circulation system.

Moreover, since the overflow tank is provided with the pipe body that reaches the detection position of the liquid level detection means provided in the liquid container,
A single liquid level detection means can be used to detect the liquid level of the liquid storage container and the overflow tank, and the device can be simplified accordingly, and at the same time, the overflow tank can be manufactured inexpensively as a disposable type. You can

[Brief description of drawings]

FIG. 1 is a sectional view showing an outline of an apparatus constituting one embodiment of the present invention, FIG. 2 is a sectional view of an apparatus showing another embodiment of the present invention, and FIG. FIG. 4 is a sectional view showing the inside of the developing unit shown in FIG. 3, and FIG. 5 is a sectional view showing the inside of the cleaning unit shown in FIG. FIG. 6 and FIG. 6 are plan views showing a panel plate of the same apparatus, and FIG. 7 is a block diagram showing a configuration of an electric control system thereof. Figures 8a to 8f
8 is a flowchart showing a control operation of the microprocessor shown in FIG. 7. 3 Photoconductor drum 4 Main charger 5 Developing device 7 Transfer charger 8 Separation unit 9 Cleaning unit 16 Recording paper cassette 24 Fixing unit 28 Liquid inlet of developing device 29 …… Liquid outlet 30 …… First tank (black developer tank) 30r …… Second tank (red developer tank) 30g …… Third tank (green developer tank) 30b …… Fourth tank (blue developer) Liquid tank) 30i …… Cleaning liquid tank 34, 34r, 34g, 34b, 34i …… Upper limit detection switch 90 …… Overflow tank 91 …… Drain pipe 92 …… Air bleed pipe

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Manabu Mochizuki 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Company (72) Inventor Yuichi Kobayashi 1-3-6 Nakamagome, Ota-ku, Tokyo Shares Company Ricoh

Claims (1)

[Claims] 1. A closed overflow tank, which constitutes a part of a liquid circulation system and which communicates with the container via an overflow pipe, is provided in addition to a liquid storage vessel into which liquid flows from other than the circulation system. In addition, the overflow tank is provided with a pipe body such that the opened upper end reaches the detection position of the liquid level detecting means arranged in the liquid container. Detection device.