JPS6187165A - Image formation device - Google Patents

Abstract

PURPOSE:To restart easily copying and to form an image with high quality successively from the 1st sheet after restart by stopping the rotation of a rotary body after rotating the rotary body by prescribed cycles at the interruption of a power supply before the formation of an image and the completion of transfer. CONSTITUTION:A drum 47 is rotated by 1.12 revolution after the end of copy cycles by the number of times set by a numeral key 31, and during the period of said additional revolution, the surface of the drum 47 is electrostatically cleaned by driving an AC charger 69, a preexposing lamp FL1, a blank exposing lamp and a whole surface exposing lamp FL2. Dielectrification is executed twice during the revolution of the post rotating LSTR by 1.12 cycles to remove uneven dielectrification. After transfer, the drum 47 continues to rotate and the surface of the drum 47 is cleaned by a cleaning device constituted of a cleaning roller 48 and an elastic blade 49. Consequently, copying can be easily restarted and images of high quality can be formed successively from the 1st sheet after restart.

Description

[Detailed description of the invention] Tree 151! The present invention relates to image forming apparatuses such as copying machines.

In conventional copying machines, if the power switch (main switch) of the copying machine is turned off before the copying cycle is completed, the power supply line to the load to complete the copying is turned off, the copying operation is immediately interrupted, and the machine is placed in a hibernation state. , it was common to hold power for a predetermined period of time to delay line cutoff.

Therefore, if the switch is turned off during continuous copying, various condition setting data such as the number of copies will be canceled, making it difficult to perform the next copying operation, and copying may be resumed regardless of paper jams remaining in the machine, increasing accidents. In addition, especially in transfer type copying machines, there is a drawback that the photosensitive drum is alerted to the fact that the surface potential is extremely non-uniform, making it impossible to resume copying.

The present invention eliminates these drawbacks, thereby making it easy to restart copying, and when restarting, it is possible to form a high-quality image from the first copy. Particularly in cases where the copying operation is executed by a computer, the display and sequence can be conveniently controlled.

One feature of the present invention is that it has a cassette stand with two upper and lower stages,
Two types of cassettes (or two of the same cassette) can be set at any time. Selection of the upper and lower cassette stands can be made with one touch using the selection key on the operation panel, and the set cassette sizes are displayed on the operation panel for both the upper and lower cassettes.

Another feature is that in consideration of ease of use, the information and operations necessary for copying operations are centrally located on the operation panel on the front right hand side. Moreover, the panel is equipped with a touch sensor, allowing operation with just a light touch.

In addition, the transfer copier uses a roller development method to ensure faithful reproducibility in both line copy and solid copy.

Furthermore, an automatic control circuit is provided which uses a potential sensor to detect the surface potential of the photosensitive drum, which is the most important factor in the image forming process, and when it is outside the specified range, promptly restores the potential and guarantees a constant contrast at all times.

Also, during standby, the rotation of the drive part is stopped, and a timing belt is used for drive transmission to reduce the noise generated from the machine.

In addition, a one-chip microcomputer is used at the heart of the electrical control to integrate a single circuit and improve reliability. It also has a self-diagnosis function and a fail-safe function in the event of trouble. In Figure 0, which is a perspective view of a copying machine, 1 is a tray 2 for storing copied paper, a cover on the top of the main body, 3 is a rear cover of the main body, 4 is a left door on the top of the main body that can be opened and closed, 5 is a document cover, and 6 is an operation cover. , 7 is the right cover, 8 is the operation panel, and 9 is the power switch that supplies power to most of the main unit.

10.11 is the main body that stores the transfer paper and the removable upper stage,
Lower cassette, 12 is a transport handle.

13 is a socket for a key counter, and 14 is a front door that can be opened and closed.

FIG. 2 is a plan view of the operating section 8 of FIG. 1.

In the figure, 28 and 29 are keys for selecting the lower and upper cassettes, 30 is a slide lever for setting copy density, and position 5 is the standard density. 31 is a numeric key for setting the number of copies, 32 is a clear key for canceling the number, 33 is an interrupt key for copying another number before the copying of the set number by key 31 is completed, 34 35 is a copy key for commanding the start of copying, and 35 is a stop key for stopping the copying operation during continuous copying of a set number. These keys use a flat type touch sensor, so they are extremely easy to operate. It becomes easier. Note that the copy key switches at 90±50 gr, and the other keys switch when suppressed by 120±50 gr, and returns when the suppression is removed.

15 to 21 are warning indicators from the main unit, all of which are displayed as pictograms.

Reference numeral 15 denotes a paper feed check indicator that lights up when a bee paper jams inside the machine, when the original illumination lamp lights up abnormally, or when no signal is generated from the Hall IC under the optical mirror rail.

16 lights up when there is no cassette in the cassette stand selected by the paper/cassette replenishment indicator, or when there is no paper left in the cassette set in the cassette stand.

Reference numeral 17 denotes a replenishment liquid replenishment indicator, which lights up when the amount of developer in the developing device falls below a specified amount.

Reference numeral 18 denotes a toner replenishment indicator that starts to light up when toner is no longer replenished (when the toner bottle is empty) even though the toner concentration in the developer in the developing device is below a specified value.

19 is a key counter inspection indicator that lights up when the key counter is not inserted into the socket of the main body.

23 is a wait/copying indicator, and this display blinks if (1) the temperature of the fixing heater is lower than the specified value when the power switch is turned on.

(2) Since it remains lit from the time the copy start key is pressed until the end of exposure for eel end copying, it is easy to know when to replace the original.

Reference numeral 20 is a set display for the number of copies per copy, and when the desired number of copies is set using the numeric keypad, the set number of copies is displayed in seven segments. You can set 1 to 99 sheets at a time. When 30 seconds have passed after copying is completed, or when the clear key is turned on, the set number of sheets automatically returns to Ol.

Reference numeral 22 indicates the number of copies per copy, and when the copying operation starts, the count is displayed for each copy.

The number is added and displayed until it matches the set number.

21 is an interrupt indicator that lights up when you press the interrupt key.
Turns off after interrupt copying is completed.

24 and 25 are upper and lower cassette size indicators that display the sizes of the cassettes set in both the upper and lower tiers.

With this display, you can see the cassette sizes of the upper and lower cassettes at the same time.

26 and 27 display the one (cassette stage) where keys 28 and 29 are turned on.

Figure 3 is a cross-sectional view of the copying machine shown in Figure 1! Yes, Figure 1, Figure 2
The structure and operation will be explained with reference to the figures.

The surface of the drum 47 is made of a three-layer seamless photoconductor using a CdS photoconductor, and is rotatably supported on a shaft, and is driven by a main motor 71 that is activated when the copy key is turned on.
Starts rotation in the direction of the arrow.

When the drum 47 rotates by a predetermined angle, the original placed on the original platen glass 54 is illuminated by the illumination lamp 46 that is integrated with the first scanning mirror 44, and the reflected light is transmitted to the first scanning mirror 44 and the first scanning mirror 44. It is scanned by a two-scanning mirror 53. The first scanning mirror 44 and the second scanning mirror 53 move at a speed ratio of 1:1, so that the original is scanned while the optical path length in front of the lens 52 is always kept constant.

The above reflected light image is the lens 52. After passing through the third mirror 21, an image is formed on a drum 47 at an exposure section.

The drum 47 is simultaneously neutralized by a pre-exposure lamp 50 and a pre-AC charger 51, and then corona-charged (for example, +) by a secondary charger 51.

Thereafter, the image irradiated by the illumination lamp 46 is slit-exposed to the drum 47 at the exposure section.

At the same time, corona charge removal of the opposite polarity (for example -) to AC or - is performed by a charge remover 69, and then a high-contrast electrostatic latent image is formed on the drum 47 by uniform surface exposure using the entire surface exposure lamp 68. . The electrostatic latent image on the photosensitive drum 47 is then developed with liquid by the developing roller 65 of the developing device 62 and visualized as a toner image, and the toner image is easily transferred by the pre-transfer charger 61.

The transfer paper in the upper cassette lO1 or the lower cassette 11 is fed into the machine by a paper feed roller 59, and is transferred to the photosensitive drum 47 with accurate timing by a register roller 60.
sent in the direction.

The leading edge of the latent image and the leading edge of the paper can be aligned at the transfer section.

Next, while the transfer paper passes between the transfer charger 42 and the drum 47, the toner image on the drum 47 is transferred onto the transfer paper.

After the transfer is completed, the transfer paper is transferred to the drum 47 by the separation roller 43.
The paper is separated and sent to a conveying roller 41, guided between a hot plate 38 and presser rollers 40, 41, and fixed by pressure and heating, and then transferred to a tray by an ejection roller 37 via a paper detection roller 36. 34. - After the transfer, the drum 11 continues to rotate and its surface is cleaned by a cleaning device composed of a cleaning roller 48 and an elastic blade 49, and the process proceeds to the next cycle.

As a cycle executed prior to the above-mentioned copy cycle, there is a step of pouring the developer into the cleaning blade 49 while the drum 47 is stopped after the power switch 9 is turned on.

This is hereinafter referred to as "pre-wetting", and this is to flush out the toner accumulated near the cleaning blade 49 and to provide lubrication to the contact surface between the blade 49 and the drum 47. After the pre-wetting time (4 seconds), the drum 47 is rotated, the residual potential and memory of the drum 47 are erased using the pre-exposure lamp 50, the pre-AC static eliminator 51, etc., and the drum surface is cleaned using the cleaning roller 48 and cleaning blade 49. There are steps to do. The purpose of this, hereinafter referred to as pre-rotation, is to make the sensitivity of the drum 47 appropriate and to form an image on a clean surface.

The pre-wet time and pre-rotation time (number) are automatically changed depending on various conditions (described later).

In addition, as a cycle after the number of copy cycles set by the number key 31 has been completed, there is a step of rotating the drum 47 several times to remove residual charges and memory on the drum using an AC charger 69, etc., and cleaning the drum surface. be. This is referred to as J, i lower rotation, and is intended to leave the drum 47 electrostatically and physically clean.

In the apparatus, reference numeral 45 denotes a standard white plate provided at the end of the glass 54, and the reflected light is involved in setting the bias voltage of the developing roller 65.

67 is a surface potential meter placed close to the drum to measure the surface potential at the center of the drum.

A zero-rotating body that detects potential from an alternating current waveform obtained by rotating a cage-shaped rotary body, and compares it with a predetermined value to optimally set the discharge current of the charger 51°69 and the bias voltage of the developing roller 65. It has a motor that rotates.

56 is a blower for cooling the inside of the machine, and its control operation is combined with the PROS sequence.

57 and 58 are lamps and CdS for detecting the presence or absence of paper in each of the upper and lower cassettes.

Although not shown, a door switch is provided that is turned on when both the upper left door 4 and the front door 14 of the main body are closed, and when the door switch is turned off, a part of the power supply that cannot be shut off even if the power switch 9 is turned off is also turned off. Furthermore, the remaining 1rt inside the main body
A sub-switch will also be provided to shut off all sources (central control unit). This sub-switch has the same function as when the power cord of the copier is unplugged from the office outlet.
This machine has the feature that the operating status of the door switch and power switch is read into the control circuit as a signal and used as conditions for control processing.

(Optical system) Figure 4-1 is a partial cross-sectional view of the optical system in Figure 3, and the numbers 1 are the same as those in Figure 3.
is an effective scanning area, and intersection 3 is an O/towing area. 1 Normally, the forward movement ends at a maximum of 11 and 2 and the backward movement process begins (hereinafter referred to as reversal).

HALL is a Hall element installed at a predetermined position ε corresponding to the first mirror stop position before starting, HAL2゜HAL3 is a Hall element installed midway through the forward movement path of the first mirror, and MS4 is a Hall element installed at a predetermined position ε corresponding to the first mirror stop position before starting.
This is a microswitch installed at the end of the mirror overrun area.

HAL'1 to HAL'3 operate when a magnet installed on the base approaches the first mirror as it moves, outputting a high-level signal, and each signal stops the optical system. This is the condition for controlling the operation of the paper feed roller, the lighting control of the document illumination lamp, and the operation control of the registration roller. MS4 is for forcibly and preferentially stopping the forward movement of the optical system at a predetermined position when the first mirror is not reversed at this position. This prevents the optical system from rushing toward the other end of the main body due to trouble with the optical system control section, and can prevent damage to the equipment. The optical system has three inversion positions in 12 (corresponding to A4 size, B4 size, and A3 size), which means that the pulses generated by the rotation of the main motor 71 are This corresponds to the position where the double movement control is performed by counting a predetermined number separately.

(A tip) FIG. 4-2 is a plan view of the vicinity of the blank lamp 70 in FIG. 3.

The blank exposure lamps 70-1 to 70-5 are turned on while the drum is rotating, except during the 'ja' light, to erase the charge on the drum surface and prevent excess toner from adhering to the drum. however.

Since the blank exposure lamp 70-1 illuminates the drum surface corresponding to the potential sensor 35, it is turned off momentarily when measuring the dark area potential with the potential sensor. Further, in B-size copying, the image area is smaller than A4 or A3 size, so the blank exposure lamp 70-5 is turned on for the non-image area even while the optical system is moving forward.

The lamp 70-0 is called a sharp-cut lamp, and the drum part that is in contact with the one-separation guide plate 43-1 has a
Light is irradiated to completely erase the electric charge in the area, preventing toner from adhering to it, and preventing the gap from contaminating the width.

This sharp cut lamp is always on while the drum is rotating.

(Developing Device) FIG. 5-1 is a sectional view of the developing device, FIG. 5-2 is a sectional view of the developing roller, and FIG. 5-3 is a perspective view of the era roller.

In the figure, 100 is a conductive sponge containing the developer in the developing roller 65, 101 is a net-like insulator covering the sponge 100, and 102 is a metal roller surrounded by the sponge 100, to which a bias voltage is applied by a DC power supply 103. . 105
107 is a refresh roller, and 107 is a developing electrode.

The developing roller is immersed in developer during standby.

When copying begins, it contacts the drum surface with constant pressure and begins to rotate counterclockwise in synchronization with the peripheral speed of the drum. First, edge development is performed using the developer accumulated between the auxiliary electrode plate 104 and the developing roller 65 (area a).

Because the developing roller 65 is in pressure contact with the drum surface, near field development is performed with the developer seeped out of the sponge 100 of the developing roller (region b). The restoring force of the sponge in the developing roller is used to absorb excess developer on the drum surface after development into the developing roller (area C).

Capri is also prevented as much as possible by adjusting the bias voltage of the developing roller 65.

During copying, the developing roller is wedge-shaped between the refresh roller 105 and the drum, and is rotated while being pressed against the drum. The developing roller that is in pressure contact with the drum surface discharges the developer contained in the sponge and when it leaves the drum, the sponge expands and absorbs (squeezes out) the excess liquid on the drum surface. When pressed, the sponge 100 spits out the old developer contained therein, and then, when separated from the refresh roller 105, absorbs fresh developer again. A developing electrode 107 is provided between the refresh roller and the developing roller because it is necessary to fill the space with sufficient developer. In order to prevent dirt from adhering to the developing electrode 107, the same bias voltage as that of the developing roller 65 is applied. In this way, each time the developing roller rotates, the cycle of discharge → absorption → discharge → absorption is repeated.

A cleaner blade 106 of the developing roller removes toner lumps adhering to the mesh of the developing roller to prevent clogging of the mesh, thereby improving the sharpness of the copy image quality.

The developer in the container is simultaneously pumped onto the auxiliary electrode 104 and onto the cleaning blade 49 by a pump motor (not shown). Further, the developing roller 65 is in the state shown in the figure only during development, and at other times it descends to separate from the drum surface.

This prevents toner from being deposited on the drum surface unnecessarily and prevents the sponge from deforming.

Fig. 6 is a transmission block diagram of the drive system in Fig. 3. The 2-digit numbers in Fig. 0 are the same as in Fig. 3;
03 is a synchro belt that transmits power from the main motor, 604 is a gear that transmits power from the main motor onto the drum 47, 605 is a gear that transmits drive to the separation roller 43, 606 to 608 are clutches, and 609 and 610 are This is a solenoid that moves the constantly rotating paper feed roller up and down onto the paper after the power supply 9 is turned on.

When the main motor 71 starts rotating, it rotates the developing roller via a synchro gear, a synchro belt, etc., a drum, a separation roller, a conveyance mechanism, and a refresh roller. Further, at the same time as the main motor starts operating, the developing roller is pulled up by the torque motor and brought into pressure contact with the drum surface.

The optical system is forward clutch CL-1 or reverse clutch CL.
-2 is activated, the drive from the main motor is transmitted and the i! I! ! Do f+.

Copy paper is fed into the machine by lowering a paper feed roller upon generation of a paper feed signal.

Timing clutch CL-3 drives the timing roller.

In this way, the driving necessary for the copying operation is performed by one main motor 71. In addition, move the roller 65 upwards.
There is a torque motor (described by dk) that moves the developer downward, and a motor that stirs the liquid in the developing device 62 and pumps the liquid to the blade 49° developing electrode. In addition to the aforementioned exhaust pro-7 motor, there is also a first intake fan motor that cools the vicinity of the fixing device, and a second intake fan motor that cools the vicinity of the developer, which are synchronously controlled.

FIG. 7 is a block diagram of the electrical control system in FIG.
03 is an alternating current (AC) load such as a main motor, 704 is an AC driver such as an amplifier for driving the load 703,
705 is a direct current (DC) load such as a clutch or a solenoid, and 706 is a timing operation of an AC load 703 and a DC load 705, lighting of each display on the operation unit 8, operation of an automatic control system, operation of self-diagnosis, etc. It is a DC control unit for control, and it receives signals from the operation@B key and a state detection sensor (
The above control is performed by inputting a specific signal from the signal 1 surface potential control unit 708 using a Hall element, microswitch, etc.).

(Sequence) FIG. 8 is a time chart of each sequence step. Turn on the sub switch SWI.

When the power switch SW2 is turned on, the pre-wet operation (FWET) is performed for about 4 seconds, then one rotation of the drum front rotation (INTR) is performed, and then the control rotation (CON) is performed.
TR), and if the copy key is not turned on, the fourth standby state 1 (STBY4) is reached.

The control rotation N is a drum rotation in which a potential sensor alternately measures the potential of a bright area and a dark area each time the drum rotates, and a surface potential control circuit brings the potential of the drum surface closer to a target value. Controlled rotations N are performed up to a maximum of three rotations.

The control rotation 1 is only 0.6 rotations of the drum, and the threshold potentials of the bright and dark areas are controlled only once during this period.

The control rotation 2 is used to measure the bright area potential using the semi-standard light intensity from the original illumination lamp immediately before starting copying, and to determine the bias value to the developing roller. When copying is started, control rotation 2 is always executed. However, when the copy signal is not output, this controlled rotation 2 is just idle rotation.

Post-rotation (LSTR) rotates the drum an additional 1.122 times after copying is complete, and during this time, the AC @ electronics, pre-exposure lamp, blank exposure lamp, and full-surface exposure lamp are operated to electrostatically clean the drum surface. do.

During LSTR, the AC charger current is approximately 100 µA (typically 2
00 pA) to prevent the drum surface from becoming too negative.

The reason why LSTRt-1, 122 rotations is performed is that since the positive potential between the positive charger and the AC charger is higher than that in other parts, the static electricity is removed twice to eliminate uneven static removal.

5TBYI~4 indicates that the drum has stopped and is in standby mode after I and STR are completed. After 1 hour of controlling the mask computer, standby is set to 5.
Changes from TBYI to 5TBY4 (each within 30 seconds).

(within 30 minutes, within 5 hours, over 5 hours), 5 TBY when pressing the copy start key
The start sequence differs depending on the state in which the

When the copy start key is on (Figure 8-2) SCF
W is forward mode. Here, the document illumination lamp is turned on, and the document image is projected through the mirror and lens in synchronization with the circumferential speed of the photosensitive drum. Also, during 5CFW, the Hall IC on the optical rail controls the movement of the copy paper as described above.The 0 inversion signal is output from the microphone computer CPU according to the cassette size by adding the clock pulse after the generation of the conveyance timing signal. It will be done.

5CRV is in vkdX mode, and the optical system returns to the stop position at approximately twice the forward speed. To continue copying, the original illumination lamp is turned on again using a signal from the Hall element for paper feeding control during the reverse mode.

In the final copy, it takes 16 clocks (40mm) from the time the optical mirror returns to the home position until it enters the LSTR.
We have set a period of This is to ensure reliable transfer to the trailing edge of the copy paper. After 16 clocks,
The AC charger facing the LSTR is turned to weak AC, the other chargers are turned off, the developing roller descends, and the drum surface is electrostatically cleaned.

Regarding turning on the copy start key in each of the above process modes, in Figure 9, in process mode (5 ()), no matter what point you press the copy start key, the control rotation 2 (
After executing up to CR2), the 0 surface potential control where the optical system starts is performed 4 times for both vL and vD, and 2 times for control rotation.
(CR2) determines the developing roller bias.

When the copy start key is pressed during controlled rotation 2 (CR2) in mode (2), the process immediately shifts to CR2, the developing roller bias is determined, and the optical system starts.

If the copy start key is pressed during post-rotation (LSTR) in mode (2), LSTR is completed. lNTR is 19
The reason for this is 2 clocks (1,133 rotations) in order to secure the time during which the developing roller is brought into pressure contact with the drum surface and the lighting stabilization time for the entire surface exposure lamp.

When in mode ■, it immediately enters forward rotation (INTR, the same as ◎). Since it is within 30 seconds from the end of the previous copy, the potential control is executed using the previous control value, and no correction control is performed especially during this period.

However, CR2 is executed.

In mode (2), 0 surface potential control is executed once for both vL and vp, starting with a total of two revolutions by INTH of l clock.

When in mode ■, it starts after 3 revolutions.

Since some time has passed since the previous copy was completed, surface potential control is executed twice for both vL and Vo.

Mode ■ is the same as case ■.

In mode Φ), if the cover is opened due to a jam occurring during copying, or if the power switch is turned off during standby, and if the power switch is next turned on within 5 hours, the mode (mode) will be used.

If the copy start key is pressed before CRI, the copy operation will start; if it is not pressed, LS will be pressed after CR2.
TR becomes 5 TRY.

Mode ■ is for when more than 5 hours have passed, and is the same as case ■.If you do not press the copy start key, CR2 and then L
It will be 5 TBY from STR.

In case (2), if the power switch SW2 is turned off before CR2 and then turned on again, the sequence starts from PRE-WET. Furthermore, if SW2 is turned off and on after LSTR, either case (2) or () will be the sequence.

Also, if the power switch is turned off during the copy cycle,
Immediately the process moves to LSTR, and after LSTR ends, the drum stops.

Time measurement for 30 seconds, 30 minutes, and 5 hours is performed from the drum rotation stop regardless of standby or power switch off.This is done by the long timer function of the computer program unless the sub switch is turned off.
The above control is performed according to the elapsed time of the timer when the start key and power switch are restarted.

Mode O) is when the copy start key is pressed between PF when the optical mirror of the final copy is moving forward and PF' when it is moving backward.

PF' (original illumination lamp lighting signal) when the optical mirror is moving backwards
The illumination lamp lights up, the optical mirror returns to its stopped position, and the next copy cycle begins immediately. The situation is the same as continuous copying.

Mode 0 is when the copy start key is pressed after passing PF' while the optical mirror of the eel end copy is moving backwards and before returning to the stop position.

Since PF' (original illumination lamp lighting signal) has already passed, after the optical mirror returns to the stop position, 17 clocks are counted, during which time the original illumination lamp is turned on, and the next copy cycle begins.

Mode @ is when the start key is turned on during 16 clocks, and the operation is performed immediately in the same way as mode q).

Mode - Even if the start key is turned on previously (of the final copy), the CPU will not respond, and the same goes for the numeric keys.

Note that PF' is not generated as a signal during the final copy.

Figures 9-1 and 9-2 are operation timing diagrams of each operating load of the device. The former is a timing diagram when the copy key is not turned on after the main switch is turned on, and the latter is a timing diagram when the copy key is turned on.

In the figure, DRMD is a signal for driving the main motor, H
VDC is a signal that energizes a high-voltage transformer that supplies voltage to each DC charger and the previous AC charger, HVAC is a signal that simultaneously energizes a transformer that supplies voltage to an AC charger, and BLWD
Proa F1. is used to cool the inside of the aircraft. A signal that drives the fan F2 and the developing cooling fan F3, DVLD is a drive signal for the motor that pumps up and stirs the developer, RLUD is a signal that raises and lowers the developing roller, and TSE is a signal that activates the ATR and turns on the liquid concentration detection lamp. Turn on. DVLB is a signal for applying bias voltage to the developing roller and electrode;
PF is paper feed position signal, RG is registration position signal, OHP
is the optical system stop position signal, FWCD is the forward clutch on signal, RVCED is the reverse clutch on signal, PFSD
is the paper feed solenoid activation signal, RGCD is the register clutch activation signal, IEXP is the document exposure lamp on signal, 5
EXP is a signal to set the standard light intensity, BEXP is a blank lamp ON signal, STBM is a signal to turn off only the standard blank lamp, and VL 1 is a prerequisite for detecting the dark area surface potential by this lamp.

VD and VL2 are potential measurement signals, ISP is an initial reset pulse signal for potential measurement, and SMD is a signal for rotating the surface electrometer.

The numerical value in the figure is the number of pulses CL generated by the rotation of the main motor. The operation on/off of each load is carried out by counting the number of pulses from the operation change point to the change point by the CPU, since the number of pulses is stored in the ROM.

In addition, a full exposure lamp FLI, a pre-exposure lamp FL2. Sharp cut lamp LA90! , blank lamp LA90B
(For B size) is operated in synchronization with the drive signal of the main motor.

The output of the high voltage AC transformer is reduced to about half during the process during LSTH. Further, blank lamp LA906 (for A size) and the remaining blank lamps LA903 to LA905 correspond in operation timing to the BEXP signal. Since the operation of each part is clear from the time chart, the explanation will be omitted.

Note that symbols such as R and D indicate that the signal is output from the corresponding port of the CPU.

(Control circuit) Figure 1θ is a circuit diagram of the DC control unit. 111 in Figure 1 reads the input signals to the input terminals 11 to 1G, decodes the logic, performs arithmetic processing, and outputs a predetermined signal from the output terminals 01 to 03B. Central processing unit C that outputs (timing operation signal 1 table no signal)
A PU, for example, consisting of a computer chip element.

Reference numeral 112 is a matrix circuit for inputting signals from key operations of the operation unit, detection operations of Hall elements, etc. to the input ports I1 to 4, and reference numeral 115 is for inputting one of the input conditions in the matrix circuit 112 to the input ports. A decoder that outputs a probe signal (scanning signal) decodes and outputs signals from output ports 013 to 016. A generator 113 generates a series of pulses in accordance with the rotation of the main motor (drum rotation), and inputs the pulses to the CPU in order to determine the drive timing of each operating load.

114 is a detection switch operated by a paper detection roller;
An activation signal is input to CPU III to detect a jam.

116 is a 7-segment numerical display, segment) LE
D, connected to display decoder 117 to activate each digit. 117 is connected to output ports 017-020, selects one of the segments of the display 116, and lights up in response to one of the scanning signals a-d. The signal a-d dynamically lights up the display with a pulse that repeats the output of a-+d. Note that the display device ITS is reset, etc. by the output ports 031 to 033.

Reference numeral 118 is an automatic recovery circuit that monitors the operation of the CPU III and turns off the power to the CPU in the event of an abnormality and then automatically turns it on again.

Reference numeral 119 is a display device for displaying a warning mark for weight a on the operating section, and is activated by outputs from output ports 024 to 029. 120 is a circuit for dimming the original lamp and correcting the start-up; 1.21 is a fixing heater operation and temperature control circuit; 122
．． 123 is a cassette size detection circuit and its decoder;
24 is a size display, 125 is a fan, and a blower operating circuit.

126 is a main motor operating circuit, 127 is a document lamp lighting circuit, and 128 is a cassette stage selection circuit.

129 is a developing roller elevating circuit, 130 is a paper feed/registration operating circuit, 131 is a bending/backward operating circuit, 132 is a front,
Full exposure lamp lighting circuit.

133 is a high voltage AC circuit, and 134 and 135 are input and output balance groups.

In this machine, the display 116 displays the number and size of the keys according to the human power, and the display changes or is maintained depending on the process, and the display 119 is used to issue an alarm on the machine status and release or maintain it. Also, the on/off timing operation as shown in Fig. 10.11 is executed using key manual data and basic timing pulses, and furthermore, the on/off timing operation as shown in Fig. 10.11 is executed at 118°, 120°, etc.
121 etc. to execute various safety controls and compensation controls,
The circuit configuration is not limited to this example, and there are various variations.

When a well-known microcomputer is used as the central processing unit 111, its interior generally includes ROM, RAM, and INP.
UT, 0UTPUT.

Has ADA. ROM reads key input.

A memory in which the contents of a display sequence and a process operation sequence are assembled and stored in advance in code in order, and for example, the program of the flowchart shown in FIG. 18 showing an example of execution is stored in a binary code microphone program system. RAM is a data memory that stores the program memory's own data and input data such as the number of copy settings, number of copies, cassette stage, etc. INPUT is a port for inputting key signals and detection signals, and 0UTPUT is an output port for latching output signals. , ADA has an accumulator function that temporarily stores data from the input port and data to the output port.

It is a processing unit that has an ALU function that performs calculations and logical judgments on data from ROM, RAM, and input/output ports.

Here, the input data is input processed according to the execution of the program in the ROM, is taken into the ACC in a specific step, is logically judged, and proceeds to the next step, and the copying operation load is reduced by 1jJll.

FIG. 11-IN11-6 is a diagram of each AC load control circuit in FIG. 7.

(Environmental Heater) Figure 11-1 shows the environmental unit circuit. This prevents the properties of the photosensitive drum and developer from changing depending on the environment such as temperature and humidity, which would adversely affect copy image quality.

Sub switch SWI, door switch MSI.

2. When all circuit breakers CB2 are on and the power switch SW2 is off (all off in the above diagram), and the temperature is below 18°C, a full-wave rectified wave is supplied to the drum heater H2 and the developer heater is turned on. . When the temperature is 18° C. or higher, a half-wave rectified wave is supplied to the drum heater H2, and the developing device heater H3 is turned off. It is clear from the drawing that the thermoswitch TS is turned on when the temperature is below 18°C and turned off when the temperature is above 18°C. In this example, the two heaters can be controlled to be energized in different modes using an extremely simple circuit. Note that NEI is a neo lamp that lights up when the main switch SW is turned on.

(Motor, High Voltage Transformer) Figure 11-2 is a drive circuit diagram of the motor, transformer, etc.

In the figure, 131 is a triac that energizes the motor, 132 is a photocoupler for triggering the triac, and 1
33 is a Zena diode that is used only when the load is the main motor and supplies a constant voltage to the photocoupler.

DC controller output (DRMD signal for main motor)
When is 1, a current flows through the LED in the photocoupler 132, and the LED emits light, causing the Cd in the photocoupler to
The resistance of S decreases and current flows through the gate of triac 131. This makes the triac conductive,
AC loads such as motors and transformers operate. When the output from the control section is O, the opposite is true; the load does not operate.

In-flight cooling fan FM1. Heater exhaust heat fan FM2. Developing cooling fan FM3, pump motor M802. The pre-AC/pre-transfer/transfer high voltage transformer HVTI is also a similar circuit.

In the present invention, even if the power switch is turned off during the rear rotation of the drum, the drum does not stop rotating, but rotates for a predetermined amount, stops, and then turns off the power. Connect to a power supply that does not turn off even when the power is turned off (voltage is not stabilized). Other loads are regulated 24V
Connect to power. Therefore, in the case of a main motor, a Zena diode is inserted.

(Torque Motor) FIG. 11-3 is a circuit diagram of a torque motor that controls the elevation and descent of the developing roller.

In the figure, 134 is a triac for rotating the torque motor 66 to the right, 135 is a photocoupler for triggering the triac 134, and 136 is a triac for rotating the torque motor 66 to the left.

137 is a photocoupler that triggers the triac 136, and RLUD is a control signal for raising and lowering the developing roller, which is output from the CPU III. MS is a switch provided at a position that is turned off when the developing roller is lowered to a predetermined position.

Explain the operation. When the drum starts rotating forward, CPU III
sets RLUD to 1, turns on the photocoupler 135, turns on the triac 134, and rotates the torque motor clockwise. The developer roller is therefore raised until it touches the drum surface. Note that the contact of switch MS changes to NC in the middle of the rise.

When the developing roller hits the drum with constant pressure.

Although the engine is stopped, the torque motor remains on. In other words, the torque motor is slipping while the developing roller is pressed against the drum with a constant pressure. This maintains good development and aperture effects as described above.

When copying is completed and post-rotation begins, RLUD becomes O, turning off thyristor 135 and turning off thyristor 137 instead.
Turn on. Therefore, the torque motor rotates counterclockwise to lower the developing roller. When the developing roller is lowered to a predetermined position, the switch MS3 is turned off as shown in the figure, and the thyristor 137. Turn off the triac 136.

Therefore, the torque motor stops rotating. Therefore, the developing roller remains stopped at that position due to its own weight. By the way, when the main switch SW2 is turned off as shown in the figure, even though the developing roller is rising, the developing roller is lowered by its own weight to the position of the switch MS3 and stopped. This prevents the roller from deforming due to the pressure of the developing roller on the drum when copying is interrupted and the drum is left unattended, and also prevents the roller from staining the drum surface.

(Front, full-face exposure lamp) In FIG. 11-4, 138 and 140 are ballasts for lighting the full-face exposure lamp and the front exposure lamp, and 139 is a relay for operating the ballast. Power switch SW2 is on and control signal DRMD for driving the main motor is 1.
At this time, the relay 139 is turned on, its contact is switched to the No side, and each lamp is lit via the ballasts 138 and 140. When the signal DRMD is 0, the lamp is turned off.

(Fuser Heater) Figure 11-5 is a lighting circuit diagram of the fuser heater.
HI is a thermistor located on the back side of the heat plate 38 (opposite to the fixing surface), Hl is a nichrome heater, FSI is a temperature fuse, 141 is a triac that switches the energization of the heater H1, and 142 is a rectifier that full-wave rectifies the AC power supply voltage. ,
Reference numeral 143 denotes a photocoupler composed of a photothyristor b, and the thyristor b turns on when it receives the light from the LED a. 1
44 is a transistor whose collector is connected to the gate G of photothyristor b, 145 is a diode for level shifting, 146 is a backflow prevention Ichikawa diode, FSRD is l when the temperature detected by thermistor THI is 175°C or less,
In the above case, the signal from the temperature control circuit becomes O, and the LED is a light emitting diode that displays the signal state.

When the heater surface temperature is 175° C. or lower, FSRD 1 turns on the LED and turns on LED a of the photocoupler 143. This generates a gate signal for thyristor b. If transistor 144 is on, the gate of thyristor b falls to Ov, so the thyristor does not turn on. However, when transistor f' is off, Since the gate is disconnected from the Ov line, that is, the thyristor is turned on only near Ov in the AC sine wave (depending on the threshold voltage of the transistor).

This makes it possible to minimize electrical noise when the power to the heater is turned on or off. Thyristor 1
43 is turned on, the power supply AC4R321→D307-A
-Q311→0307-C-+R322→FSI-H1
A current flows through the route of the current AC, and the triac 141
is turned on, so the fixing heater H1 is also turned on.

Further, when the heater temperature is 175° C. or higher, the signal FSRD becomes 0, and the heater H1 is also turned off, performing the operation opposite to the above. Its operation diagram is shown in Fig. 17-1.

The surface temperature of the fixing heater H1 is normally controlled by a thermistor THI and a DC controller so as to be maintained at 175° C., but this is done to reduce power consumption during standby or when a jam occurs.

The control temperature is switched to 140° C. by a relay K102 shown in FIG. 12-1 provided in the DC controller. Therefore, in that case, the FSDR becomes 0 when the temperature is 140 to 175°C.

Furthermore, when the main switch SW2 is turned off (see figure), the heater H1 is turned off.
However, the power is cut off.

(Temperature control, protection circuit) Figure 12-1 shows the fixing heater temperature control and disconnection alarm circuit.

In the figure, K102 is a relay to change the set temperature of the heater, VRIOI is a variable resistor to set the set temperature to 175°C, VR102 is a variable resistor to set it to 140°C, THI, R1
12 and 113 to form a bridge. Q103 is signal F
Operational amplifier that outputs SRD, Ql 04 is operational amplifier that outputs when disconnection of thermistor THI is detected, LED1
03 and 104 are indicators for each FSRD to indicate when the wire is disconnected. When drum rotation signal DRMD is 1, relay K1
02 shows the state as shown in the figure, the operation of the operational amplifier Q103 is turned on and off based on 175°C, and the heater H1 is turned on and off at 175°C.
Adjust the temperature to maintain the temperature. When the signal DRMD of THL becomes 0, the contact of relay KZO2 is switched and the set temperature is set to 140℃.
Set to . The temperature of the operational amplifier Q103 is then adjusted to maintain the temperature at 140°C. This characteristic diagram is shown in Fig. 17-2.

When the thermistor THI is disconnected, the balance of the bridge including R114 and R119 is lost, turning on the operational amplifier Q104, turning on the transistor Q105, and setting FSRD to 0.

Therefore, overheating can be prevented by turning off the power to the heater H1.

(Original lamp lighting circuit) Figure 11-6 shows the lighting circuit for the original illumination lamp.
In the figure, reference numeral 301 is a release in the normal state as shown in the figure, which turns off the power to the lamp LAI in the event of an abnormality. The lamp is turned on by operating the torch light in response to the timing output IEXP signal from the DC controller. Please refer to the above-mentioned time chart for the timing chart.This device changes the copy density by changing the amount of light emitted from the lamp LA. For this purpose, a dimming circuit is provided to change the phase of the amount of current supplied to the triac according to the amount of displacement (VRloB) of the density lever 30 to change the amount of light.

As a safety measure, in the following situations.

Controls the document illumination lamp to turn off.

(1) When the document illumination lamp is lit when the drum is not rotating.

(2) If the optical system forward clutch does not operate properly after the document illumination lamp turns on.

(3) When the optical system forward clutch is not activated and the optical system is not reversed (detected by the overrun microswitch MS4).

(4) In the unlikely event that the above condition cannot be detected,
If the temperature near the original exposure lamp rises abnormally (169
(Detected by temperature fuse FS2 that melts at ℃).

Relay K103 performs the dimming operation by lever resistor VR106 in the state shown in the figure, and performs the same amount of dimming as when lever 5 is operated in the reverse state. Standard light intensity signal 5EXP
The standard white plate is irradiated with light of the amount of 5, the bright area potential (on the photoreceptor) is measured, and the bias voltage of the developing roller is determined according to the value.

(electric circuit) @Figure 14 is the power supply circuit in Figure 7.

15VAC is AC 1 that has only been transformed with a transformer TI.
Outputs 5V. This power supply is
It is converted to 0VDC and used for the power supply of the microcomputer, and is turned off when the sub switch SW1 is turned off or the power plug PI
Always supplied unless removed.

+24VDC is a completely stabilized 24V DC after transformation and rectification, and the supply is cut off when the power switch SW2 is turned off.

+5VDC is fully stabilized direct current after transformation and rectification.
Since the input signal of Q704 is received from +24 VDC, the supply is cut off when the power switch SW2 is turned off.

U32V is DC 32V with a lot of ripple, which is only transformed and rectified without passing through a stabilization circuit, and the supply is not cut off just by turning off the power switch.UH24V is a simple stabilization circuit after transformation and am. There is a slight ripple (approximately +5% voltage fluctuation) in the 24V DC that passes through.

Even if the +24VDC supply is cut off by turning off the power switch, the P
If HLD is 1, continue supplying.

Supply is cut off only when PHLD becomes 0.

13VAC is AC 1 that is only transformed by transformer T2.
It does not turn off just by turning off the power switch at 3V.

D701-704 are full-wave rectifiers, C701-703 are smoothing capacitors, Q701-708 are elements constituting a well-known stabilization circuit, LEDs 701-703 are output states, PHL
This is a light emitting diode that monitors D. The PHLD signal is a signal generated in synchronization with the drum drive signal DRMD.
When DRMD is 1, PHLD is also 1. This means that even if power switch SW2 is turned off during post-rotation, etc.
This is because the drum is rotated by the UH24Vii source until the post-rotation is completely completed.

(Self-diagnostic circuit) Figure 12-2 shows a diagnostic circuit that checks the operating state of the CPU.

In the figure, Q133 is a type that starts timed operation at input 1 to port 2 and outputs level l from port l during that time period.
Q130 is a transistor turned on by timer output, Q
131 is a transistor that turns off the +IOV computer power supply.

Q134 is a thyristor that shorts the +IOV input line.

Normally, the pulse signal O5C is repeatedly output from the CPU, so the transistor Ql29 turns on and does not allow the timer to operate. When the pulse stops, Q129 turns off and starts the timed operation, and Q131 causes the +IOV line. Turn off. If you time chip after this turn off, Q will return again.
131 is turned on. Thyristor Q134 turns on via Zena diode ZD109 to cut off the output when +10V becomes excessive.

Figure 12-2 for sequence and CPU self-diagnosis,
This will be explained in detail with reference to FIG. 18-3.

A step for generating a self-diagnosis pulse is provided at the end of subroutine A. In the figure, the bypass flag is set and reset at the beginning of routine A when the routine A is entered. This flag activates the bypass timer after being reset and is set after the timer time (abnormality detection), thereby outputting an abnormality detection signal from the output port 036. The bypass tire is a timer for a time corresponding to executing the branching step (discrimination routine) of the main flowchart having routine A on a scheduled rotation. The switching flag is set and reset repeatedly every time routine A is executed, and is used to output pulses from the output port 036 in an oscillating manner. Pulses from 015 are 10-100
When passing through the 0 discrimination routine that inverts 1.0 once every m5ec in normal time, the bypass flag remains reset, so the oscillation pulse does not stop.When that time is exceeded, the pulse stops and the circuit shown in Figure 12-2 The timer Q133 is set to cut off the power supply line +IOV. A normal routine is passed, for example, when the paper feed signal PF and the registration signal RG can be detected within a predetermined time after the optical system starts moving forward.

In Figure 12-2, Q129 turns off when the pulse oscillates from port 15, turns on when it stops, and negatively triggers timer Q133. Therefore, the timer outputs 1 from port 3 for a time of 11 minutes determined by the time constants of R190 and C113. do.

Q131 is rectified by the full-wave rectifier 126 and smoothed by C116, and the voltage of 16V is applied through the breaker CBIOI. The operation timing of the 0 circuit is shown in Figure 6-3. The base of Q131 is a Zener diode ZD10.
6 and has a voltage of approximately 10.5 V. Therefore, Q1
31 outputs a stable DC voltage of +IOV.

Since Q130 is connected in parallel with ZD106, when 1 is output from the 3 terminals of Q133, Q130 turns on, Q131 turns off, and the +IOV current becomes Ov.
(Figure 16-3).

That is, when the oscillation output from the output terminal 036 of the microcomputer stops oscillating, the power to the microcomputer is turned off for the time T1, and the microcomputer is reset.

Note that the microcomputer executes the program from the initial address when the power is turned on. This resets the RAM contents.

Furthermore, even if the microcomputer CPU's flocram sequence or the copying machine's own sequence is reset as described above due to destruction, etc., if no oscillation pulse is output from 036, +IOV will be turned on and off at a time interval of approximately 2 x T1. Various displays lit by the CPU repeatedly flash at the same cycle to notify the copying machine user of an abnormal condition.

The microcomputer power supply circuit shown in the southern part also has the following functions. First, if the voltage at the emitter of Q131, that is +IOV output, increases for some reason, it will exceed 11V in terms of Zener voltage of ZD109, causing scR, Q134
becomes conductive and the DC current from D126 becomes CBIOI.
, R192, the circuit breaker CBIOI is opened to perform a protection function against overvoltage application. Also, the rectified voltage from the bridge diode is C1
When TLs+ is turned on, the voltage applied to C116 rises slowly due to smoothing by 16, so the rise time of the emitter voltage (+10V) of Q131 is usually slow, and this rise time can lead to malfunction of the microcomputer. In order to speed up the voltage, first connect the voltage coming through R192 to a Zener diode ZD107. By applying the voltage to the base of the emitter-grounded NPN transistor Q132 through R187, Q132 is prevented from turning on unless the voltage rises to about 8V determined by ZD107. When Q132 is off, the base of the transistor Q130 is connected to R19 via R185 and R186.
By connecting Q131 to Q131, when a voltage of about 2■ is applied through R192, it becomes on state and Q131 becomes off state. This state continues until Q132 is turned on.Therefore, after the rectified voltage rises to about 8V, the +IOV power supply rapidly rises to about 8V.

Incidentally, in the present invention, it is also possible to turn on oscillation or set the level 1 to trigger the timer Q133 in the event of an abnormality.

(Input Circuit) FIGS. 15 to 1 show a matrix circuit (multiplexer) for inputting touch keys and input signals to the CPU.

In the figure, O to 9 are the contact points of the numerical keys, and C, 5TOP.

,,I/R,C0PY,UP,LOWtt each lJ
7 key, stop key, interrupt key, copy key.

This is the contact point for the cassette upper row designation key and the cassette lower row designation key, and closes when the key is turned on. By grounding CPl-CF2, jam detection operation for delay retention is not performed (CPI).

These ports are for canceling the wait time (CF2), for making multiple drum rotations for surface potential measurement (C20), and for making multiple copies (infinite times) (CF2). SC,S
L and SR are signals from microswitches that are activated when a cassette is inserted, POEM is a paper-out detection signal for that cassette, PWSA and PWSB are signals caused by turning on each main switch and door switch, and TEMP.

FLW and KCT have various fixing temperatures and no liquid.

Key counter error detection signal, EXP, JAM, TN
are each document illumination lamp ON, jam detection, and low toner density detection signals; RG, PF, and OHP are register signals, paper feed signals, and optical system stop position signals.

O~(φ corresponds to the probe output terminal from the probe decoder (FIG. 7). 11~I4 correspond to the input ports of the CPU.

151-160 are AND gates.

Oscillation signals of several kilohertz are output from O to ■ in the DC controller each evening without overlapping timing.

For example, if 1 is sent to I4 while l is being output from ■, this means that the numeric keypad has been pressed.

In this manner, the microcomputer reads input signals, performs calculations, storage, and control.

(Segment display) Figure 13-1.13-2 is a 7-segment LED display that displays the number of copy sets and the number of completed copies.
ED603, 604, 601.602 is a 7-segment display for the second digit and first digit of the copy number, and the second digit and first digit of the set number, and this is the segment 8 to g as shown in Figure 13-2. and is connected to the signal sources ① to ②. a to d are connected to a probe signal source that selects each digit.

For example, in the case of the LED 602 (l digit) that displays the number of sheets set, when 1 is output from a, ■, u), and ■ are O.
When this happens, LEDs a, b, and c in the 7 segments light up and display the number 7.

The axd outputs an oscillation signal of several kilohertz without changing the timing of the a to d pulses, and in synchronization with this, signals 1 to 2 are output.

Therefore, each digit blinks very quickly, so it appears to be constantly lit.

This display performs display operations in response to numerical keys, start keys, interrupt keys, etc.

For example, in the case of copying 23 copies, when the power switch SW2 is turned on, the set number display 20 and the copy number display 22 will each display 01 and 00, and the 2. By sequentially turning on the key 3, 02°OO is displayed, and then 23.00 is displayed. When the copy start key is turned on, it remains at 23.00,
When one sheet is fed, 23.01 is displayed, and thereafter, 23.01 is displayed every n sheets fed. n is displayed, and when 23 sheets are fed, 23.23 is displayed. The copy operation is stopped when the copy key is not turned on again before the copy ends. Press to display 01,00. However, when the copy key is on, it is 2 when it is on.
Display 3.00.

If the interrupt key 23 is turned on at the 10th copy during copying, the display changes from 23.10 to 01.00. When the number key 5 is turned on again, 05.00 is displayed and the start key is pressed to start copying 5 sheets. When one sheet is fed, 05,
01 is displayed, and when 5 sheets are fed, 05 and 05 are displayed, and then 23.10 is displayed again. Then press the start key to 2
3.11--1-23, 23 will be shown in Table 1.

Also, if you turn on the stop key 35 while interrupt copying is in progress for 5 sheets, the execution will be interrupted and the number 23 before the interrupt will be displayed on the display.
Display to, and then press the start key to execute the remaining copies. However, if the stop key is turned on twice, the subsequent start key will copy from 23.00.

(Input operation) Turn on the power switch 9. At this time, if the temperature of the fixing heater is below the specified value (175°C).

The wait/copying display blinks. Raise the document table cover 5, place the document face down on the glass, and align it with the size index.

Use the cassette selection keys 28 and 29 to select the platform (upper or lower) that contains the cassette to be used. When the original switch 9 is turned off and then turned on, the lower cassette table is automatically selected. It is convenient to set the cassettes you use most often in the lower row.

Adjust the copy density lever according to the original (standard is 5).
．． If you want to make it darker or lighter, use 9.1 each).

The required number of copies (1 to 99 copies) is set using the numeric keypad 31, confirmed on the cassette number display 20, and the start key is turned on. If you cannot set it even after pressing 4 on the numeric keypad,
Or, if you make a mistake in setting the number of sheets, press the clear key and set it again. Display oi and oo.

After copying starts, from when the original illumination lamp turns on until the final copying optical system is reversed.

Even if you press the clear key, numeric keypad, or upper/lower cassette selection key, you cannot change the settings.

If the out-of-paper indicator in the cassette lights up during copying and the copying operation stops, load copy paper, insert the cassette into the main unit again, and then press the copy start key to automatically calculate the remaining number of sheets. Copied.

If you want to stop the copy operation during continuous copying, press the copy stop key to stop the copy operation after completing the copy operation at that point. The number of copies per copy display shows the number of copies made at that time and stops. 0 Next, press the copy start key.
The number of copies per copy display starts from 00, and the set number of copies will be automatically copied.

If you press the numeric keypad to set the desired number of copies and leave it for about 30 seconds, or after copying is finished (drum stops)
If you leave it for 0 seconds, the number of copies per set will be 0.
Cleared to 1.00.

In the case of interrupt copying, the operation 1 display as described above is performed.
'By copying with IA, the number of copies, the number of sets, and the cassette stage at that time are stored in the memory RAM in the CPU. During copy interruption, open the document cover, replace the original, set the number of interrupt sets, and also select the cassette size (column) (display the selected column and the cassette size in that column). When the copying of the number is completed, the contents displayed on the display device are automatically changed to the contents saved in the memory as described above. The cassette size indicator also displays the original stage size.

If you want to stop copying during continuous copying.

When the copy stop key is pressed, the copy operation at that point is finished and then stopped, and the optical system is reversed.

Or, after reversing, the number of one set copy is displayed instantly,
The size display and membrane display return to the display before the interrupt.

It doesn't matter if you press the interrupt key during interrupt copying.

After the display of the number of set copies returns, pressing the -81 key allows interrupt copying to be performed again.

If you press the stand clear key, it will be cleared to 01,00.

- If you press the copy stop key, the display of the number of copies per set does not change, but if you press the copy start key, the display of the number of copies per copy starts from 00.

(DC load) Figure 13-3 shows the paper feed drive circuit, and in the figure, SLI, S
L2 is a solenoid for lowering the paper feed rollers of each upper and lower cassettes to feed paper, UPUS and LPUS are signals with an output of 1 to lower the paper feed rollers of each upper and lower cassette; The timing detection signal PF and the cassette selection key signal are output from the CPU. Note that if the total counter is off for some reason (signal CNTD is 0), no output is made.

Figure 13-4 is the drive circuit for the optical system forward clutch.
In the figure, CL2 is an electromagnetic clutch, 5COV is a signal that is set to 1 by the optical system overrun detection microswitch MS4,
5CFW is a forward signal.

When 5cov is 1, an optical system advance signal is generated (scpw
0), the power is applied and the optical system forward clutch (CL 2)
works.

However, if the optical system remains at 5CFW O and the optical system does not invert at a predetermined position, MS4 is activated and 5cov becomes 0 (24v is cut off).

Cl3 is turned off even though 5CFW is 0.

The reverse clutch drive circuit is the same as that in which Cl3 is set to V. The operating principle of the resist clutch corresponds to the latter.

Figure 15-2 is a basic clock generator.

Generates signal CL.

When the power switch is on, +24V is supplied, so the LED is always lit. At this time, the phototransistor PTr is turned on, the transistor Tr is turned on, and the output 0UTPUT becomes 0.

Moreover, when the light shielding plate comes to the slit shown in the figure, the light from the LED is blocked, so the output becomes 1. Output 1.0 is repeated by rotating the light shielding plate in synchronization with the rotation of the main motor (8
8 clocks/second).

Figure 15-3 shows the paper detector at the paper discharge section, and the signal JA
Generates MP. 153 is the light shielding arm, 154 is the 15th
155 is a piece of paper. When the paper hits the roller 36, the 7-m 153 is pushed in the direction of the arrow and the 155 is a piece of paper.
54 is hit by light and outputs a signal l.

Figure 15-4 shows a cassette size detector, and the cassette stand has an upper stage 155. 4 each in the lower row 156
Individual microswitches are installed to send signals for determining cassette size, etc. to the DC controller.

When each switch is turned on (indicates 0, contrary to the figure), the size is as shown in FIG. 17.

Note that MS 902 and 906 check the presence or absence of a cassette (1 in the figure).

FIG. 12-3 is a diagram showing the relationship between the cassette and the display section.

When the upper cassette selection key on the operation panel is pressed, a C55I signal is output from the DC controller.

If you press the LED 629 (upper selection display) and the lower cassette selection key, the CSSO will turn on the LED 630 (lower selection display).If no cassette is inserted at this time, the microswitch on the cassette stand will be actuated. MS901 is not displayed in the upper row.
1, MS903 1. Since it becomes MS904 1, DC
PCBL l signal is output from the controller and LED6
34 lights up (paper/cassette replenishment display). MS902 does not operate when the cassette is not complete, so it lights up in the same way. Also, when there is no paper in the specified cassette, Cd55
PCEL becomes 1 from the circuit No. 8, and the LED 634 lights up. When a B4 cassette is inserted, MS901 and MS903 are actuated, so MS901
0. MS903 0°MS904 1. At this time, 1 is output to the B4 port of the DC controller, so LED607. LED 608 lights up.

FIG. 15-5 shows a circuit for inputting the power switch-on signal PWSA and the door switch-on signal pwsB to the CPU, which are connected to the +24V line and the U32V line, respectively.

This signal holds the display.

Figure 18-1 is a schematic diagram showing the flow for performing the above control. When the sub switch and power switch are turned on, the timer for pre-wetting is executed, the switch-on for jam killing, etc. is read, and the numeric keys are pressed manually. It is determined whether the copy key is on through the entry flowchart, and a pre-rotation step and a copy cycle step are executed.

FIG. 18-2 is a flowchart after the subswitch is turned on, and the CPU starts operating when the subswitch is turned on.

When the sub switch is turned on, the computer CPU will switch to ROM.
Start program processing. First, input to the CPU interrupt port and execution of internal timer interrupts are prohibited, the output port and input port are reset, and the RAM is cleared (1
), and set the data to display 01.00 on the output port 1 display (2), but since the display power 24V is not turned on at this point, it will not be displayed.Next, input port 14.13 is set. Set and input data PWS
A. - Take in PWSB and determine whether the main switch and door switch are turned on (3). If not turned on, repeat the above operation. When turned on, set the timer flag and time flag, and set the lower cassette flag. Set and display it (4), turn on the developing motor, pro-aperture motor, and sensor motor, clear the register that stores the number of sheets in a, and set the copy display flag and key reception possible flag. (6) Next, set the input port 12 and take in the signal CP2 to determine whether or not to kill the weight (
7) If so, set the flag for omitting rotation, otherwise reset the kill flag and determine whether 5-hour timer puffer 3 is 1 (8), if not, 30-second timer flag is set. 1 or not, and if so, sets a timer set flag 2 for pre-wet execution, sets a 4-second timer, and executes a timer operation for pre-wet. After 4 seconds, the clock number 170 for forward rotation is set in a predetermined area of the RAM (10), and the main motor is turned on for forward rotation.

Figure 18-3 is a subroutine for key entry and signal entry, which is provided in the routine to be executed at the judgment step in the main flowchart of Figure 18-1.18-2, and Figure 15-1. The subEXC in the figure is the interrupt cancellation routine, and the subc
opy is a copy key entry routine, and subCP is a cassette key entry routine.

In the sub-CP, the cassette stage reading routine is performed in the 18th-
It will look like Figure 4.

First of all, when the key enable flag is not 1, it means that there is no response even if the cassette selection key is pressed, and it is when the main and door switches are off, there is a jam, copying is in progress, etc. In this case, the upper and lower cassette flags are Becomes unchanging;
Reading is performed only when the key enable flag is 1. This program routine is passed once every 10 to 100 m5ec, and each flag is set and stored almost instantaneously when the selection key is pressed. Proceed to the reading routine for that location detection.

This flag is also changed programmatically even when the selection key is not pressed.

First, when the main switch is turned off, the following happens.

When either the door switch or the main switch is turned off, the program loop shown in the figure is rotated, and this loop continues until both the door switch and the main switch are turned on and forward rotation begins. In this loop, if the door switch is determined to be off even if the main switch is on, this embodiment considers the copy to be interrupted, so the various resets shown in the figure are not performed and the cassette flag is also left unchanged. Become. On the other hand, when the main switch is turned off, the lower cassette flag is set and when the main switch is turned on again, the lower cassette is selected first.

For reading and canceling interrupt copy, see section 18-6.18-7.
As shown in the figure. Here the conditions for interrupt copy (number,
Cassette stage) information is retained even when the door switch is turned off, making it convenient for operation. Also, even if it is an interrupt copy, pressing the stop key twice will completely cancel the number of copies. Also, during interrupt copying, the cassette stage can also be recalled from the display. In other words, when the power is turned off by opening the door switch, the interrupt state and interrupt display are not cleared and remain stored, and when the power is turned on again (door switch on), the state before the door switch is opened is displayed and interrupted when the copy key is turned on. The condition is canceled.

If the interrupt state is to be canceled manually, it will be canceled when the stop key is pressed according to the program shown in the figure.

That is, in the flowchart of Fig. 18-8, when the m interrupt flag is 1 (during interrupt copying), when the stop key is pressed, the interrupt flag display is reset, and at this time, the state of the number of copies made before the interrupt is displayed. However, the "temporary stop flag 2" is set to determine whether or not to continue copying from that state.

Also, since this part of the routine is repeated at intervals of lO to roomsec, if the stop key is once released and then pressed again, the "temporary stop flag 2" is reset and the continuous copying state is released. That is, both interrupt copy cancellation and copy stop can be accomplished by pressing one stop button, and the distinction is made automatically.

Next, when interrupting and canceling the interrupt, the program will be as follows.

That is, at the time of an interrupt and when the interrupt is canceled, the information is stored temporarily in the save memory from a part of the memory to diagnose whether the number of copies has been counted up or not, as well as other conditions and the selected cassette to display one. The data in a part of the save memory is moved to a part of the memory that is used for display judgment, and is immediately replaced. Therefore, when the interrupt is canceled, the state before the interrupt is restored including the cassette stage. However, at the time of an interrupt, the cassette remains unchanged and copying starts from O unless the cassette is reselected by the following program (details are omitted).

In the CPU III, the input terminal I5.16 is a port for interrupting the program progress and executing a specific program (including 114) by inputting an input signal to this port.The former is a drum clock signal (CP), and the latter is a paper Detection signal (
An interrupt occurs at the rising edge of JAMP). 0 sentences are CPUI
A pulse oscillator with a pulse width of 1 psec is used to run CPU II, +lOV is a port for applying the output voltage of the power supply shown in FIG. 12-3 to the CPU 111, and G is a port for grounding CPU III.

The ROM stores a program according to the flowchart shown in FIG. 18, and the RAM has flags shown in Table 1 provided at each address in the RAM. This flag increases to 1 when set and becomes 0 when reset, and the program progress is controlled by determining its state.

Table 1: Checking the reverse clutch is explained in Figure 18-4. In Figure 0, SUB DETCT is the routine for this purpose. When the optical system is not in the stop upper position after copy key-on detection and before exposure scanning (1), the reverse clutch is checked. On (port 06
1) (2), and then, when the optical system reaches the stop position by the time the clock reaches a predetermined count, the reverse clutch is turned off (3) and the process proceeds to the step of turning on the document lamp.
However, if the predetermined count is reached, it is assumed that the reverse clutch is damaged and the process proceeds to the jam routine, and the relay KIO
Turn on I and set the jam. The OHP position determination routine includes the routine shown in FIG. 18-11, so a self-diagnosis pulse is generated to check whether the position determination routine has been completed.

be able to.

S in figure 0 explaining lamp check by figure 18-7
UB EXP is a routine for checking abnormal lighting of the lamp, and is executed before exposure scanning. Determine the start key (copy flag) (1) L, when on, set the number of copies display to OO, then determine whether the lamp is lit (3)
), it is checked by reading the lighting signal LAI from the lamp lighting detection circuit of No. 1111-6r into the CPU via the matrix circuit of Fig. 15-1 using the timing signal of ■. 1) No. 18-
Execute the jam alarm routine shown in Figure 10.6 When the light is not lit, output level l from the output port to light the halogen lamp, turn on the forward clutch and start re-exposure (Figure 18-4). The lamp check routine is also provided in the routine shown in FIG. 18-6 that starts scanning after the completion of copying and in the middle of continuous copying of the set number.

The jam detection operation will be explained. 18-17, the number of drum pulses C is slightly larger than the number corresponding to the time required for the paper to normally reach the exit detection roller 36 from paper feed.
In order to count the number of L, step (1) and subsequent steps are executed. The delay jam flag and the above pulse number are set at the time of paper feeding (Figure i18-5), and from that setting time the pulse C
Each time L occurs (Fig. 15-2), the number is decremented by 1, and when it reaches 0, it is determined whether the jam has been killed or not, and the paper check of the exit roller 36 is performed. (3) If there is no paper, the jam routine (Fig. 18-9), and when there is 0 paper on standby, the number of paper counters in the machine are set to -l and the process moves to the accumulated jam check routine. This is because the paper passes through the roller 36 normally. A similar clock count is used to check whether the paper is stored or not. This time differs depending on the paper size, so set the number of clocks for each paper as shown in the figure (4).
), and as above, add -1 and (5) count the set number, check the paper again, and this time, if there is paper, add l to the in-machine sheet counter and proceed to the jam routine. 0 If there is no paper, then Perform counting operations for the purpose.

The jam routine is shown in the first s-tos and proceeds to the standby l routine (Figure 18-8) through which it first sets each flag in the figure.

Reset, decrement the weight-up mark, turn off the copy display (1), reduce the number displayed on the copy number display by the number on the machine (2), and perform the 5UBOFF routine (18th - Figure 7) Execute (3) to output a jam signal from the port. This turns on relay KIOI (Figure 15-5) and jams mark 1.
5 is displayed (4), this relay KIOI remains on until the reset switch SW3 is manually released. Also, the output l from this relay KIOI is inputted to the input port of the CPU as JAMR. 5 clock pulse CL
After counting, the main motor signal is set to 0 to stop it and move the drum rotation to standby.

The standby routine is shown in Figure 18-8, and measures the idle time while the start key is not turned on. First, TMS
Set ET flag 1.2.3, determine weight killing, and determine the shortest pre-rotation time for each display timer,
Set the idle timer time (1) and start the CPU's internal timer for measuring this time (2)
), if the start key is turned on (3) before each timer counts up, the process moves to the pre-rotation step. However, if there is a jam (determine whether the input port signal JAMR is 1 or not), key reading is prohibited (5), and the time measurement routine 5UB is executed at least until the relay KIOI is released.
Repeating SET, 5UBSET is based on the idle timer.

This is a routine that measures for 5 hours, 30 minutes, and 30 seconds and sets each flag. During these 30 seconds, the specified output port is set to 0 and the fan (blower) is turned off (6). If there is no jam, when the interrupt copy is finished (stopped),
And when there is paper, please measure the display timer for 30 seconds 7) 1
Turn off the interrupt display and set the set number and copy number displays to 01 each.
．． 00, turn off the halogen lamp, and proceed to 5UBSET.

Detailed explanation of door switch and main switch operation determination.

Conventionally, copying would stop immediately when the power was turned off.

All that was considered was keeping the power on for the necessary time and letting the interruption occur.

In this device, the operating status of each power switch is input as signals PWSA and FWSR, and control conditions are changed or stored in memory depending on the status of each switch. This is clearly indicated in various parts of the flowchart in FIG. This will be explained with reference to FIG. 14 and FIG. 15-5.

The input AC power in FIG. 14 generates power supply voltage (+10V) for the microcomputer on one hand, and is supplied to the power transformer T2 via the door switch (MS t , MS 2) on the other hand, and is supplied to the power transformer T2 from the secondary side to D701. Approximately +32V is output after being rectified and smoothed by C701. Furthermore +32
6. V is stabilized at +24V via the main switch and transistor Q703. U32V and +24V Ha8
ZD l l 1 , each transistor Q135 . Input to the base of Q136. Therefore, depending on the on/off of the door switch and main switch, the collector iFI of Q135゜Q136
The force becomes as shown in fjS 16-4 diagram. U32V,
+24V produces similar rise and fall times due to C701 when each switch is turned on and off. In this example, ZDIIO, Z
Q135.Dllll is turned on by applying 4V and 22V respectively. This makes the response of Q136 different. T1. T
2. and T3 is 100m5ec. By the way, Q
135. When the collector signal of Q136 is Ov, the door switch is turned on, and both the door switch and the main switch are treated as on, and when it is 1, the door switch is treated as off, and at least one of the door switch and the main switch is treated as off, so the switch status After detection, the state of each switch is determined as shown in the flow diagram.

CB1-3 in Figure 14. CB701-703 are breakers.

LFI is a low pass filter.

Control when the main switch SW2 is turned off during the copy cycle will be described with reference to FIG. 18-9. In this case, the rotation is completed after a predetermined period of time and then the machine stops, or the paper jam check that has already been fed is completed and the machine stops. This allows the surface of the photoreceptor to be in an appropriate state for waiting, so the lifespan of the photoreceptor is not compromised, and the machine is not left unattended with jammed paper left behind, allowing smooth restarting of the machine after it has stopped. be able to.

During a copy cycle (after turning on the copy start key,
If a power-off signal is detected by turning off the main switch or door switch (before the rear rotation is completed) (:1
S18-15) The flag shown in the figure is reset (1)
, Check the on/off status of the door switch (2),
When the door switch is on, it is determined whether the current state is in backward rotation (3) and whether backward rotation has finished (4). Set the post-rotation timer to make the post-rotation, and if the post-rotation is not completed yet, let the post-rotation remain and stop the rotation only when this is completed (5), set the idle timer (6), and when the weight is killed, shorten to 5. If not, set it to 30 seconds. Then, the number table tlXrh is set to 01 (Cera)) and 00 (Completed), the lower cassette is designated, the interrupt copy is canceled, and the process waits. When the door switch is off, the post-rotation is not executed, but the setting of the above-mentioned idle timer and completion of the timer is checked (7), the pre-rotation speed setting routine is exited, and the process waits. Start by turning on the door switch and main switch (8) and move to the next standby (in case of jam) or forward rotation (in case of no jam) step (9).

Here, since the clock pulse CL caused by the drum rotation is generated even during the post-rotation, an interrupt trigger is applied to the port 5 even after the main switch is turned off during the copy cycle. Therefore, the first
The clock count subroutine CNT shown in FIG. 8-17 is executed, and the delay retention check routine therein is continued. Jam's! :, s executes the jam routine of m18-10[iN and latches the jam relay KIOI.

Further, after the delay/retention jam flag becomes 1 (check start), even if the main switch is turned off, the jam detection operation continues unless this flag is reset. By the way, this jam flag is held without being reset even when no check pulse is input (such as when the door switch is turned off). Therefore, when the door switch is turned on from off and the drum starts rotating, the jam detection operation is performed again by the clock pulse, and it is determined whether or not the transfer paper remaining in the machine has been discharged (9).

The operation of the lamp check will be explained with reference to FIG. 11-6.

When IEXP is 0, +24V is grounded, turning off the trigger signal to the triac Tr and extinguishing the lamp LAI. As a result, the photocoupler Q303 is turned off and C
Turn off 302 and turn on Q 300' to turn on the lighting signal EXP.
Set to 0. At this time, relay 301 does not operate.
However, if the lamp LAI remains lit, the EXP will be reduced to 1.
At the same time, turn off C301 and set 1 to 9 of C305.
Output. On the other hand, when DRMD becomes O and the drum motor stops and rises, 8 of C305 becomes 1, so C305
13 becomes 0 and charges C302. 2 Sunagake Q306
turns off Onle Q306. Then, l of the flip-flop Q305 is set to O to output 1 from 3. This turns on C304, turns on relay 301, and turns on lamp L.
Turn off AI. In this way, when the lamp LAI is lit when the drum is stopped, the lamp line is forcibly cut.

Since the optical system starts moving forward about 1 second after the step starts lighting, the lamp line is cut in the same way even if there is no forward signal after waiting 2 seconds. In other words, even when 5CFW is 0, 8 of C305 becomes 1, so C302 is charged in the same way as above by the lamp lighting signal, and 301 is sent to the 2 sand relay.
Turn on. If 5CFW becomes 1 within 2 seconds, C326
Turn on to discharge C302 and do not activate relay 301. After activating relay 301, turn on power switch SW.
2 is turned off (as shown in the figure), the circuit can be reset. When the power is turned on again, Q305-5 becomes O until charging of C303 is completed, and the flip-flop is reset (Q305-3 becomes O), so Q304, K2
O2 turns off and becomes usable again.

Further, when the optical system turns on the overline detection microswitch MS4 while the optical system is not moving forward, MS4 operates contrary to the diagram and cuts off the power supply line of the lamp dimming circuit. At the same time, the power line for forward clutch CL2 is also cut. (FIG. 13-4), it is preferable that the MS4 is attached to the end of the optical rail outside the overrun area.

What happens to this dimmer circuit for 1 second after the lamp starts lighting?

By providing a circuit that turns on the triac Tr for the entire period regardless of the phase set by the VR 106 and then returns to the phase set by the VR 106, the illuminance rise of the lamp LAI can be improved.

When MS4 is turned on, the level l signal stabilized at 154 in FIG. 15-5 turns on driver 156 via gate 155, thereby activating relay KIOI and lighting jam indicator 15. and main switch S
When W2 is turned off and reset switch SW3 is manually turned on, relay KIOI is reset. Therefore, when SW2 is turned on again, the reverse clutch is turned on until the optical system reaches the stop position ff (Of (P signal)), so that the optical system can be returned to its original state.

Detection control related to developer will be explained.

A magnet is installed on a float floating in the developer container liquid,
A reed switch MS802 is provided on the container side that responds when the float drops due to the liquid being reduced below the current amount. No liquid signal LEP when the magnet is far away from the reed switch
output to the input port. As a result, the replenisher indicator on the panel section lights up and stops the start of the next copy after repeated copying.

They are installed to detect the concentration of the liquid flow between the CdS submerged in the developer container liquid and the lamp, and when the amount of light received is equal to or higher than the first predetermined level, the replenishment timing TSE (Figure 9-2) is reached. A check LED installed inside the machine replenishes toner liquid.
lights up. When the amount of received light is less than the second level, it is assumed that the replenishment toner liquid is empty, the toner replenishment indicator on the panel section is turned on, and the check LED provided in the machine is turned on. Furthermore, Cd
Lighting of S is controlled in synchronization with the DVLD signal of the developer motor.

The bias voltage for the developing roller (metal 102) is changed in three ways. When the drum is not rotating, ground (GND)
) to prevent toner from adhering to the developing roller. This is effective because it corresponds to when the roller is moving down.

When the drum is rotating but there is no developing operation, 175V is applied so that the first picture is not too dark. During developing operation (No. 9-2)
DVLB) in the figure applies +50V to the drum surface potential to prevent capri. The operation timing of the BVLB is always made to correspond to the developing operation by changing the number of count clocks according to the copy size. This surface potential is detected during pre-rotation as described above.

VLl, Vo, and VL2 in the figure m9 are surface potential measurement timing signals, which are output from the output capo 010. The sensor motor in the potential measuring device rotates during the previous rotation to chop the detected potential.

VLl and VD measure the formed drum surface potential by turning on and off the standard blank lamp (other blank lamps are lit), and VL2 automatically sets the exposure lamp LAl, which is lit when the copy key is turned on, to a brightness of 5. (SEX
P signal) and the resulting standard white pattern 25 (Figure 3)
The drum surface potential formed by exposing the drum to light is measured.

Thereafter, the brightness is automatically returned to the level set by the lever 30 (FIG. 30), and document scanning is started. The bright area potential and dark area potential due to VLl and VD are compared with each predetermined value, and the difference is multiplied by a coefficient determined by the photoreceptor characteristics, etc., so that each potential is equal to the predetermined value and A:6. J: Una Q No. Vp, VAC (11th
-7 figure) is output. In FIG. 11-7, Tc1 is a DC-DC inverter that applies high DC voltage to the primary charger 51, and A
C3 is a DC-AC that applies high voltage AC to the secondary charger 69
The inverter Tc2 is a DC-DC inverter R for superimposing a DC component on the current of this charger 69 and keeping it constant.
EC is a circuit that detects the DC component of corona current, AMPL
, AMP2 are each high voltage DC timing signal HVDC1 high voltage AC timing signal HVAC and the Vp, VAC,
! :4; m, l: This is an amplifier controlled by the output of TCl and Te3. When HVDC occurs, the corona charger 51 is discharged by the output voltage of the TCI, which is determined according to the control signal Vp that sets the primary corona to a predetermined value. Further, when HVAC occurs, the corona charger 69 is discharged by the output voltage of the inverter AC5 superimposed with the output of Te3 determined in accordance with the control signal VAC for predetermining the DC component of the secondary corona. Further, the corona current detected by the resistor R12 in TC2 is fed back to AMP2 via Q7 so that only the DC component is controlled by the difference device REC and compared with a predetermined value to make it constant.

Similarly, the current in the primary corona is detected by resistor R11 in TCI, and it is kept constant through Q5 in TCI.
Feedback control of I. That is, both the surface potential and the discharge current are controlled at a constant level. Note that the ISP signal in FIG. 9-1 sets VP and VAC in order to initially discharge the primary and secondary chargers with each constant voltage before detecting the potential. The reason why the surface potential is repeatedly detected and controlled by performing pre-rotation several times is to bring the surface potential closer to a desired surface potential.

In this example, the pre-wet and pre-rotation times are controlled according to the standby time or SW2 off time, but when the sub switch SWI is turned off due to mechanical adjustment, etc., the above-mentioned self-diagnosis function is activated and the 10V power supply to the CPU is repeatedly turned off. In case,
Executes constant pre-wetting and multiple rotations before entering the copy cycle.

That is, in FIG. 18-2, the sub-switch SW1.10,
When the 15V power supply is turned on from off, the program will always proceed from power on, so set timer flags 1 and 2 at (3').
．． Set 3.

Setting all these flags is the same as leaving it alone for more than 5 hours. Therefore, in step (8), which determines whether the standing time is 5 hours or more, set and execute pre-wet, and in step (11), set the maximum number of rotations to 4.12
), its execution (,2-0).

In addition, when proceeding from standby to forward rotation, steps (8) and (11) are reached via (5), but if the determination (1) is made after 30 minutes or more of
3) and rotate forward l.

Set 2 and perform forward rotation for that amount.

Also, if the machine has been left unused for more than 30 minutes, the ISP flag (set before copying starts) is checked and if the a-continuation timer is up (copying has been carried out for a long time), 1 rotation 2 is set. If it is not uploaded, perform the operation (15), perform the preparation rotation, and proceed to the copy cycle.

The flowchart shown in FIG. 18 will be explained below.

In Figure 18-3, ISP on/off 13) Boat o3
is set to output the initial potential from high voltage DC or AC.

In Figure 18, on/off is to output 1.0 from the corresponding output port, so the port name is omitted.Turn on the main motor and execute the pre-rotation shown in Figure 1 (1) to clock its completion (described later). Check whether the count has increased (using a sequence counter). During this rotation, the optical system is returned to the stop position (11), and the detection and control of the drum surface potential is controlled (performed by rotation. First, the bright area potential is measured using a standard blank lamp and high voltage control is performed (2). .

After that, if the kill signal CP3 of the input port is on, it continues five revolutions and repeats the bright area detection control (12); if not, the blank lamp is turned off (3), and the turned-off drum surface becomes the sensor. When the position is reached (4) the bright area potential is measured and controlled. In addition, potential control is performed by an external circuit in Figure 11-7. Repeat the pre-rotation in this way and check whether the preset number of times has been reached 7). When it has been reached, the IS
Set the P flag, continuous timer, and idle timer. In (8) and (9), check the copy flag (set by copy key entry) and disable key entry (1).
0) Proceed to the L copy preparation cycle, and after passing the copy key waiting period, proceed to the post-rotation mode.

In Fig. 18-4, first perform the position check DETCT of the optical system as described above, turn on the document lamp, set 5EXP to 1 for standard exposure (4), and detect the potential of the exposed surface (5). Determine the bias potential. After this second control rotation t) η advance latch on and move the optical system forward (
6), Check the paper feed signal PF during forward movement 7), L
If you don't check it even after a long time, treat it as a jam.

Then, turn on the paper feed solenoid (8) and lower the paper feed roller to feed paper. At this time, the in-flight ticket counter (register)
, the copy number counter is set to +1L, and the contents of the latter are displayed on the copy number display 22 (SVBDISP).

In Figure 18-5, in (1), CF2 of the input port
Check if it is on. By turning on CF2, copies are made repeatedly regardless of the number of copy sets. Furthermore, CP1~
4, ON means to turn on the switch and input level l.

When CP4 is on, or when the number of sets and copy count a are not equal, it counts 24 CL and applies a developing bias of the previously determined voltage to the developing roller (2). At the same time, an ATR counter that determines the liquid replenishment timing (described later) operate.

After that, the registration signal RG is checked and the registration clutch is turned on. Here too, if RG cannot be checked for a long time, it is treated as a jam.

By the way, if CF2 is off, when the number of copy counters is the same as the set number, and there is no interrupt copy instruction, the copy flag is reset, and if there is an instruction, the interrupt flag is also reset to prepare for post-rotation. Bias and resist. Set the number of clocks for delay jam check after turning on the registration roller (8), input the signal from the cassette switch to the input port (9), and determine the size and set the inversion timing of the optical system in three ways ( 10).

Size determination is performed by reading the 1.0 state in Figure 17.
After counting the pulse CLa corresponding to that period, the original lamp and the forward clutch are turned off to complete the exposure scan, and the reverse clutch is turned on (11). After that, 42 clocks are counted and the bias is switched to -. The pulse count in Figure 18 is based on Figures 18-17 (7) SVB CNT (
7) Performed by an interrupt program.

In Figure 18-6, check the copy flag that is reset by the stop key, etc. (1), turn off the copy display 23 when stopping (2), and enable key entry while leaving the number displays 20 and 22 as they are. . Even if it is not a stop, the copy number display 22 is set to 00 by checking the flag of the previous count-up, and the false paper feed signal PF is checked (3), and the long-time check is also performed.

After that, check the copy flag, turn on the document lamp again and check (4), and check the stop position of the optical system and its long time check (5), and check the )ner (liquid concentration is below the second level). 6) Turn on the display 18. Then perform a post-rotation. However, if the number of copies has not counted up and the copy flag is not 1, check the position of the optical system (5) with the key disabled, move the optical system forward again as shown in Figure 18-4, and repeat. I will make a copy.

In Figure 18-7, when entering the rear rotation, the copy flag is checked again (1), and when the copy key is on, the stop key at the time of interrupt is pressed twice, and when the copy number is counted up, the copy number display is set to OO (2). , check for over-lighting of the lamp, turn on the lamp, and start exposure again.

However, when the copy key is not turned on, the high-voltage DC etc. are turned off, the developing roller is lowered, and a post-rotation of 190 clocks is executed from there. After that, the copy flag is checked, and if the copy key is on by then, the copy number display is cleared, the previous rotation is executed, and the copy is started.

However, if the copy key is still not turned on, it outputs 0 to a predetermined output port to turn off the load such as the original lamp (6). At this point, the energization level of the fixing heater is changed, so the wait up flag can be reset. Check this flag and flicker the copy display when resetting. Then, turn off the main motor and go to standby.

In FIG. 18-8, the determination of C after the wait is performed by checking the flag set by the input of C10 at the input port.

This shortens the time of the installation measurement timer. When copying does not start and there is no jam (3) When the internal timer enters standby and counts 30 seconds, the number display 20
．． 22 to 01,00 and turns off the interrupt flag and interrupt indicator (7).

However, if the stop key or interrupt key is turned on and there is no paper or liquid, the above display control will not be performed.

Then, if 7M flag 1 is not set, set that flag, set the remaining time until 30 minutes, 29 minutes 30 seconds, and then repeatedly count the left timer and check 8.
) Set the TM flag 2.3 after the Mth set time. Also, even if the numeric key entry is left unattended for 30 seconds, the above-mentioned display clearing and other controls are performed.

The power-off routine and jam processing routine shown in FIGS. 18-9 and 18-1o have been described above. Incidentally, the load is turned off at the same time as step (1) in Fig. 18-9.

Subroutine A in Figure 18-11 is for sequentially executing a routine 5UBEXC for exchanging data related to interrupts, a routine 5UBCOPY for determining copy conditions related to the start key, a routine 5UBKEY for reading operation key input, and a routine 5UBPC for checking paper cassettes. This step is also a step for outputting a self-judgment pulse. Routine A with a quaternary counter installed internally
Each time the subroutine is executed, the subroutine is incremented by +1 and each subroutine is executed sequentially, and after the fourth execution, the subroutine is repeated from the beginning.

In FIG. 18-12, check whether the key entry is possible or not (1), and determine the M-inclusive flag and 1 o'clock stop flag 2 (2), (8).

The key input flag is l during copying, except during jams, etc.
It is.

(No interrupt copy, no interrupt release), the lower cassette flag is determined, the cassette stage is displayed, and the signal C5S is set to O. 3), Number display routine 5UBD I
When performing a 0-interrupt copy that executes Sr, the set number memory contents and copy number counter contents are saved to a different location in BAM, and when the interrupt is canceled, they are returned (5), and the cassette selection is performed 3) 1 Interrupt time display 20.
Set 22 to ot, oo. The number display routine executes switching of lighting digits for so-called dynamic display. The display 20 is synchronized with the change from the output port.
Each digit data of 22 is output in order (7).

Please check whether the key end is available in Figure 18-13.
), determines the input of the cassette key (1), and controls the display and flag related to the cassette key (2) 6. Inputs the no paper and no cassette signals 3) sets the predetermined flag and displays 16 lights up (4), and also reads the switch signal from the cassette and sets four size flags (5).

At 5UBKEY in Fig. 18-14, check whether or not the key is manually powered, check whether the clear key is on (1), and use the clear key to set the display to 01°00. If it is not a clear key, first set probe port 1 (Fig. 15-1), read several keys O to 3, then set port 2, and then press 4.
~7. Set port 3 and read 8.9 (3), input port 11~! The signal No. 4 inputs four bits at a time, determines whether each bit is 1.0, and performs the following determinations (checks).

It does not read even if the key is turned on three or more times (2).

If the data from the first key-on is not 0, it is displayed in the first digit of the set display 20. The data from the second key-on is transferred to the register and display corresponding to the second digit, and then stored and displayed in the empty space.

At 5UBCOPY in Figure MSl B-15, both the door switch and main switch are on (1) and the 5 copy key is on (2).

Under conditions where there is no input signal such as interrupt key, stop key, no liquid, jam, etc., a copy flag is set using the copy key and a copy display is performed (Fig. 18-16).

However, when the interrupt key is turned on, the interrupt indicator 21 is turned on and its flag is set (4).

The stop key during normal copying has been described above with a 0 interrupt that resets the copy flag by avoiding the operation caused by key chattering when the stop key is on during normal copying (6). Also, the copy flag is reset in the same way when the stop key for weight killing, the key counter is off (10), there is no paper, cassette, liquid, or jam. Liquid timer is SU
Counter operation is performed by BTMR.

5UBCNT in Figures 18-17 saves the registers in the CPU to an empty space in the RAM at the rising edge of the pulse CL that executes a program interrupt by inputting the port Q5 (7
), which determines the load operation timing of lamps, etc. The sequence flag is set at each step at the start of counting. This flag is determined and the counter set several times in that step is decremented by 1 for each CL (8), and the bias counter (8) which determines the timing of bias voltage application is
9), a counter (1) that determines the replenishment timing at low concentrations
0) is decremented by 1, and at each count-up, 1.0 is output from a predetermined output port of the CPU to make it inactive.

The jam counter has been described above.

SUBTMR in FIGS. 18-19 is an internal tire routine that operates a timer by counting pulses that cause the computer to run.

Save data since it is executed using program interrupt method (1)
Then, set and execute the blinking interval of the display 25 during wait (2), 30-second operation of pre-wet 4-second display automatic reset (3) Idle timer operation (4), Continuous timer operation (number 10 minutes) (5), activate the liquid timer (6) to output a signal late when there is no liquid.

In the following subroutine, RETURN indicates a return to the determination routine in the main flow in which routine A was executed.

Incidentally, the ISP flag shown in Fig. 18-2 also contributes to the rotation speed set when the main switch and door switch are turned off and then turned on. Further, 5UBCLRI in FIG. 18-7 sets the number display to 0 when the stop key is pressed twice at the time of an interrupt and when the number of copies is counted up. Also, in Figure 18-9, (9) is for setting the hold time after setting the number, and checking it and clearing the display (
(Display memory clear) is performed in (7), and the time of the idle timer is shortened in (10).

Correct the set time in (11) to 5 seconds in (12), and
TM flags 1, 2.3 are set when the 5 seconds set in ) have elapsed and this time has further elapsed.

To summarize the features related to the number display, etc., when the door switch is turned off, the drum immediately stops, but the RAM and display are retained, and when the door switch is turned on and left for 30 seconds, the display is cleared (auto clear).
When the main switch is turned off, the drum stops after rotation, but
Clear part of RAM and display immediately. Things that are not cleared are memories and registers related to the idle timer, clock counter, and jam counter. When a jam occurs, the number is corrected and the display is held; when the stop key is turned on, the display that was before it was normally turned on is held and auto-cleared; when the copy count is up, the display 22
0.20 is automatically cleared, and when there is no liquid, etc., the display is held at that time. 1 interrupt key clears the display. 8 In each of the above modes during interrupt, the above is followed except for the stop key.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a copying machine according to the present invention. Figure 2 is a plan view of the operation section of the copying machine shown in Figure 1, and Figure 3 is a plan view of the operation section of the copying machine shown in Figure 1.
FIGS. 4-1 and 4-2 are a plan view and a sectional view of the exposure section, and FIGS. 5-1 and 5-2 are sectional views of the developing device. FIG. 5-3 is a perspective view of the developing roller. Figure 6 is a block diagram of the drive system, Figure 7 is a block diagram of the electrical control system, Figures 8-1 and 8-2 are process mode time charts, Figures 9-1 and 9-2. The figure is a chart showing the operation timing of each part of the copying machine. Figure 1O is a circuit block diagram of the DC control unit in Figure 7, Figures 11-1 to 11- are circuit diagrams of the AC load unit in Figure 7, and Figures 12-1 to 12-3. is the DC control circuit diagram of FIG. 1θ, and FIGS. 13-1 to 13-4 are the DC load circuit diagrams of FIG. 7. Figure 14 is a power supply circuit diagram. 15-1 to 15-6 are circuit diagrams of the input section of FIG. 7, FIG. 16-1, FIG. 16-2, and FIG. 16-3. Figure 16-4 shows each part, Figure 1-5, and Figure 12-1. Figures 12-2 and 15-5 are operational characteristic diagrams, Figure 17 is the cassette switch combination front, Figures 18-1 to 18.
Figure-19 is a flowchart diagram. @ In Figures 2 and 3, 28 and 29 are cassette selection keys, 30 is a copy density setting lever, and 31 is a number key for setting the number of copies. 33 is an interrupt copy key. 34 is the copy start key. 35 is the stop key. 56 is a fan motor. 66 is a torque motor, 71 is a main motor. 67 is a surface electrometer with a built-in sensor motor. Patent applicant Canon Co., Ltd. - Ichisho Δ7 43-7 4'/ Figure 5-7 Man 5-? Figure 75-30 Screen 14 Figure 15-5 Figure 7-2 Section 9 [6-3 Figure Qqn 7--1-- 111 Figure 78-44

Claims (2)

[Claims] (1) A means for forming an image on a rotating body, a means for transferring the formed image onto a transfer material, a means for cleaning the surface of the rotating body after transfer, a means for turning on power to the device, and the power source is used for image formation and transfer. An image forming apparatus comprising a control means for rotating the rotating body by a predetermined amount and then stopping the rotation when the rotating body is shut off before completion. (2) The image forming apparatus according to item 1, wherein the control means causes the rotating body to rotate a predetermined amount and then stops when the power source is cut off after the image formation start command is issued and before the image formation starts.