DE3049321A1 - IMAGE GENERATION DEVICE - Google Patents

Description

»Rflui im / * ■ EfiMMc - patent attorneys and

WUMLING f \ INN ^ _:. ... . ... representative at the EPO

GDIiDC - Pci ι MAMM . '* " ^: " -: ..' !. ^{'\:: ..:} Dipl.-Ing. H.Tiedtke RUPE r ELLMANN - "" _ ₅ _. Dipl.-Chem. G. Buehling

30A932 1 Dipl.-Ing. R. Kinne Dipl.-Ing. R Group Dipl.-Ing. B. Pellmann

Bavariaring 4, PO Box 202403

8000 Munich 2

Tel .: 089-5396 53

Telex: 5-24845 tipat

cable: Germaniapatent Munich

December 29, 1980 DE 0932

CANON KABUSHIKI KAISHA

Tokyo, Japan

Image forming device

The invention relates to an image forming apparatus such as a copier or the like, and more particularly to a device whose power supply can be switched on in a freely selectable manner in order to initiate an image generation process or push ahead.

A conventional copying machine generally has in addition to a copy start switch a main switch voltage to electrical consumers in order to achieve process steps such as a store or an exposure in this manner can be about, and create a control device ^which is designed so that a timing control for the consumer can be achieved with it. The main switch is normally used.

various electrical consumers activated or controlled; for example, a cooling fan is operated or activated or a copier in the standby state for a start of the copying operation set.

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Deutsche Bank (Munich) loo. 51/61070 Dresdner Bank (Munich) KIo. 3939 844 Postscheck (Munich) loo. 670-43-804

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However, these electrical consumers are often switched off automatically after the copying process has ended, to eliminate the noise caused by the fan or to reduce power consumption. The main switch is therefore constructed in such a way that it can only be operated by a manual operation of a Switch handle or a button is activated and that the power supply line is then activated by means of of a relay kept switched and by releasing the relay after the copying process has ended switched off or interrupted.

The state of being switched on or off of the chip • Power supply line is often used by a user by considering the position or location of the switch handle of the main switch recognized. It would therefore give the user a very uncomfortable feeling if the Switching handle is not in a defined, preset position when looking at it. On the other hand, it would the device structure by an additional attachment of a manual cut-off switch for manual release of the Relays become very complex. A conventional device therefore has an independent safety circuit or one Protection circuit to prevent malfunction of the device and the occurrence of excessive to suppress large current in the AC voltage supply line.

It is therefore an object of the invention to provide an image forming apparatus that can overcome of the disadvantages described above has a manually operated circuit breaker.

Furthermore, a copier is to be provided in which by using a timer after termination the copying process an automatic or manually operated shutdown control is possible without a manually operated one Circuit breaker only for switching off

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must be provided.

In addition, an image forming apparatus is to be provided in which the automatic power cut-off control achievable by controlling a manual power switch and the control device from overheating is protected.

Furthermore, a device is to be created in which a manual power on and off and a automatic shutdown control by providing a power switching unit with a handle and a Control coil is achievable.

Furthermore, a self-disconnecting device responding to a malfunction occurring in it should be provided be created.

In addition, an image forming apparatus is to be provided which has a circuit breaker unit with a having first and second coils, wherein a power cut-off in response to the in one of the coil current flowing through both coils is to take place.

^{/ '> I} 25 The invention is described below by means of embodiments with reference to the drawings.

Show it:
30th

Fig. 1 is a sectional view of a copier according to the invention,

35

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Fig. 2 is a plan view of the control section shown in Fig. 1,

3 shows a control circuit diagram of a device according to the invention,

Fig. 4 is a timing diagram for the copier shown in Fig. 1,

Fig. 5 to 7 further control circuit diagrams for a

device according to the invention, and

Fig. 8 is a sectional view of the in Figs. 1, 3,

5, 6 and 7 power switching unit shown. 15th

A preferred embodiment is described in more detail below with reference to the drawing. A copier shown in Fig. 1 includes a platen 1 on which a manuscript or a Template can be placed on a rotatable drum 2, which is on its entire surface with a sensitive or photosensitive film is coated, a lamp 3 for exposing the drum 2 with the image of the original on the template plate 1, a corona discharger 5 for positive charging of the surface of the photosensitive film, another corona discharger 6 for negative Charging the surface of the photosensitive film simultaneously with the image exposure, a processing or. Developing device 8 for developing a

static or electrostatic charge image, a charger 9 for transferring the developed image a copy paper 10, a detachable cassette 11, which can accommodate a variety of copy papers or copy sheets 10 is designed to be a lead frame

12 for manually inserting the copy sheets 10 into the housing, a roller 13 for pulling out the copy sheets from the cassette, a roller 14 for transporting the

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Copy sheets from the feeder frame 12, microswitches 15 and 16 for determining a manual feed of copy papers, a registration roller 17 for aligning the leading edge of the copy paper with one edge of the drum, a roller 18 for separating the copy paper from the drum, a belt 19 for transferring or further transporting the copy paper, a fixing roller 20, a roller 21 for discharging the copy paper to a tray 22, a blade cleaning device for removal residual toner from the drum, a magnetic roller 4 for collecting the with the aid of the blade cleaning device 23 removed toner, a container 7 for receiving the toner collected with the magnetic roller 4, * a negative charge generating corona discharger 24 for removing charge remaining on the drum, a shutter 25 to block the light from the exposure lamp 3 for a predetermined time interval to be applied directly to the surface of the drum to be exposed, mirrors 26 and 28 for reflecting of the light from the lamp 3 directly onto the drum surface and a Selhock lens 27 for focusing the manuscript or the original exposed with the lamp 3, reflected light on the drum surface.

i _m Next, the operation of the copying machine will be described. If the main switch is turned on, a motor for driving the drum 2 is turned on or supplied with power, the lamp 3 is lit, the shutter 25 is opened and the

^ου drum 2 driven when the corona discharger 6 is switched on, whereby the drum surface is previously or initially cleaned of residual toner, residual charge and a storage element. The fixing roller 20 generates a start signal for the resumption of the copying

operating when the temperature of the fixing device is due to heating by an internal heater reaches a suitable level. The drum turns

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] continues until a copy switch is turned on, and the rotation of the drum is temporarily suspended if that of one in the drum drive system for the generation of η pulse units for each drum revolution, the revolution encoder provided for each revolution are counted to a predetermined number. The drum rotation described above is called the "first pre-rotation" designated. If the copy switch is turned on during the rotation or the temporary standstill of the drum

IQ mel switched on, the shutter 25 is closed, the drum 2 starts rotating again and the platen 1 starts after substantially one rotation (which is referred to as the "second preliminary rotation" in the following) with its forward movement, so that the on the original plate 1 applied manuscript or the original is slit exposed. That through the lamp 3 illuminated reflected image is slit exposed on the drum via the Selhock lens. The one on the Drum 2 applied sensitive or photosensitive film contains a top insulating layer, an intermediate layer photoconductive layer and a lower conductive layer. When the corona discharger 5 When the charged surface reaches the exposure area or station, the positive charge is passed through the negative corona discharger 6 and the image exposure at least partially electrically deleted. When the entire surface of the photosensitive film has passed the exposure station, it is on the drum surface With the aid of the light reflected by the mirror 26, an electrostatic charge image with high contrast educated. The charge image is in the development area by receiving or developing by the Toner developed as a positive image. The positive image will be in the transmission section due to the positive Transfer charge level of the transfer charger to the copy paper. The copy paper is different from the others copy papers located in the cassette 10

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the timed paper feed roller 13 separately to be fed as desired, and runs through the transmission section at the same speed due to the action of the registration roller 17 like the spinning drum. The copy paper or image receiving material is separated by the roller 18 and fed via the belt 19 to the fixing roller for image fixing and then via the roller 21 to the Tray 22 dispensed. After completion of the transfer process the drum surface is continuously cleaned by the blade cleaning device 23, electrically discharged through the corona discharger 24 and the stored charge is reflected by means of the mirror 28 ■ Light of lamp 3 removed. To make repeated copies of the same original sheet continuously, the reciprocation of the platen 1 is repeated as many times as that of a ten-key set corresponds to the number entered in the control area of the copier.

Fig. 4 shows a timing chart for a sheet of copy paper. Furthermore, in Fig. 4 are the switched-on state relevant changes are shown.

J _n Fig. 2 shows the service area of the copying machine of an electric power switch 39 (the main switch), a key switch 40 for starting the copying operation, a stop key switch 41 for interrupting a continuous copying operation, a Zehntastensafz 42 for storing the number of copies in a Memory for setting the continuous number of copies, a clear key 43 for clearing the number stored in the memory, a lever 44 for setting the density of the copy, a 7-segment display

show 45 to indicate the number stored in memory, a "wait" lamp 46 to determine whether or not

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or that the fixing roller has reached a predetermined fixing temperature, a lamp 47 for displaying the Absence of the cassette or a copy sheet in it and a lamp 48 for the display, that the container 7 for collecting the toner is completely filled with toner. A lamp 49 is on, when the copy sheet is jammed. If a deadlock occurs, the delete key and the ten key set are canceled not activated or remain ineffective; however, they can be operated during the waiting period.

The 7-segment display 45 is structured in such a way that a 1 - suppressed by a zero - regardless of the war- • te time interval when switching on the main switch 39 can be displayed. It continues after each termination a copy production a number reduced by "1" compared to the number set or displayed and, if a number of copies corresponding to the set number have been made, the set number again displayed so that a desired number of copies can be obtained without powering the ten-key set is. If 30 seconds have passed without the copier operation being resumed, then becomes over the 7-segment display 45 shows the number "1". This allows the user to resume copying without entering a predetermined number via the ten key set and accordingly resuming a smooth copying can be expected. After a standby time of 30 minutes has passed When the above-mentioned 30 seconds have elapsed, the main switch 39 becomes, as will be described in more detail below is switched off automatically.

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■ j The "Wait η" lamp 46 flashes when the Main switch 39; however, it lights up statically or permanently if the temperature of the fixing roller is not drops below a permitted fixation level, d. H. / for c a short time interval after switching off the main switch 39. In contrast, the "waiting" lamp 46 flashes when the temperature falls below the permissible fixing value. It should be noted that the "waiting" lamp 46 is steadily lit even when the temperature of the fixing roller is reached IQ has risen to the permitted or permitted value and the waiting time has passed.

if the main switch 39 is switched off, then shows. the lamp only switches off the voltage ■ jc source without lighting or flashing.

The lamp 48, which is used as an overflow indicator, is when determining the overflow status of the container 7 significant or flashing display and when detecting a toner shortage in a container 33 for the developer a static glowing display. However, the lamp can also be static in the former case light up and in the second case can be switched on and / or off. The lamp 47 for indicating the absence of paper can also be used in the absence of the Paper can be switched on and / or off and light up statically in the absence of a cassette.

If a toner shortage in the container 33 or an overflow of the container 7 is determined, the Copy operation continues until the preset number of copies is reached if a continuous Copy operation is performed based on a number preset using the ten key set, and then then prevents copying from resuming. This type of operational control is carried out in order to overcome or avoid the weak point that an alarm is given and on the other hand a

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To avoid a drop in the high copying speed, which is the consequence of an immediate termination of the copier operation would be in the middle of a series of copying operations.

Fig. 3 shows a control circuit diagram of the copier. The main switch 39 contains switches and in addition a socket unit or a socket relay with several windings. It has an overcurrent detection winding and a switch contact 152 (switch handle or »hand knob)

on and functions in such a way that the switching contact 152 when the overcurrent detection winding 150

(First coil) is forcibly opened, which takes place when the flowing current or overcurrent is greater than a predetermined value. The main switch 39 also has the function of an interrupter. It also has a winding 151 for external switching and, like the overcurrent detection winding 150, is excited by the flow of current through the winding 151, so that the switching contact 152 can be forcibly opened before the manual switch-off. The main switch can therefore be switched off automatically. However, since the switching contact 152 is arranged on the outside of the housing, it can also be operated manually,
^ s 25

HVT denotes a high-voltage transformer that generates a high voltage for the charging devices required for copier operation, L ₁₀₁ to L denote consumers such as a main motor or a fan motor for driving the drum and / or rollers. LVT denotes a low-voltage transformer for reducing the voltage to 100 V / 50 Hz, CV a stabilized electrical source for generating various DC voltages V _K , V and V as it were

DC CC

independent voltage sources that are generated by stabilizing

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Regulation of the voltage of the low-voltage transformer rectified via a rectifier circuit Rec LVT can be obtained, and CPU is a central control unit with a known microcomputer COM, which is used for timing the consumers to control the copying process in the one shown in FIG Time schedule corresponding manner and for a storage of a via the control unit shown in FIG 102 inputted key signal is provided in a memory. CNT denotes a counter for counting of clock pulses sent to it by the central unit via a line 121, which are used to set the counter serve during the time interval at which a signal is • present at a reset input RST. The frequency of the Clock pulses CL corresponds to a fraction of the frequency of an oscillator, the pulses with a duration or Period of 1 μβ generated, which is necessary to keep it operational or. Clocks of the microcomputer COM are used and are then output by this. QlOl denotes a Driver circuit with an amplifier for driving or exciting the winding 151.

The microcomputer COM contains a read-only memory ROM in which a program for the timing control shown in FIG. a key input program and a program for controlling the start and the termination of a Sequence or temporal sequence are stored using an input signal. A voltage source for the microcomputer COM is designated by Va.

How it works is described in more detail below. If the main switch contact 152 is switched on, so the voltage of the voltage source is applied to the low-voltage transformer LVT, so that the stabilizing Source or stabilization circuit CV generated DC voltages V, V and V to the central unit

C 3rd CC

CPU, the counter CNT and the operation unit 102 can be output. If the key switch 40

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switched on for the start of copying, an "On" signal is output to the central processing unit CPU, which this discriminated and processed in such a way that a control signal for the start of a copy cycle via a feed line 120 is delivered to the desired or required consumer and the copier mode with switching on a lamp 101, a main motor M101 and high-voltage output components begins. At the same time with the output signal on the lead 120 is a copy signal CPS via the lead 122 to the reset input of the counter CNT is output to reset the counter CNT to the initial state.

The copy signal is present during the copy operation or when the main motor is driven or supplied CPS at the reset input RST, so that the counter CNT is in the reset state during this time interval remain.

If the copying process has ended, the main motor is _{switched off after a standby time interval T 1 has} elapsed and the copying signal CPS is ended. The counter CNT then begins to count the clock pulses CL. After completion and non-resumption of the copying operation, if the counted number or the counter reading of the counter is equal to the counter number corresponding to a preselected time, a "COUNTER INCREASED" signal from the counter CNT to the driver circuit QlOl, whereby the winding 151 is energized and the Switching

^ contact 152 of the main switch 39 'is switched off. This allows the device to save power by switching off the power supply for the fan or the heating device contribute and eliminate the noises caused by the fan or the like. Becomes the voltage source switched on again by switching on the switching contact 152, the copying operation can be resumed be recorded because the main motor is driven and the counter CNT is reset via its reset input RST will. However, if the copy start key switch 40 is not turned on, as shown in FIG

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is, the main motor is automatically switched off after a predetermined time interval T ". Hence begins the counting process again, since the resetting of the counter CNT is ended and the counter thus causes the automatic shutdown of the switching contact 152 in the manner described above.

The resetting of the counter CNT can, however, also during the counting of the clock pulses CL due to a Key input signal from the control unit or the control area. The circuit for the above said reset can be carried out in such a way that the ten key set and / or the copy key ent- ' Speaking key input signal KIS is applied via a lead 123 to the reset input, as it is done by the dashed line is shown in FIG. The voltage source is switched off when the copy button or the key switch for the start of copying does not occur during a predetermined time interval after pressing the ten-

button set is switched on. With this type of processing, the operating behavior is improved even further, because the counter can be reset by pressing a key even if no copying is performed and counting starts when the device is not

· "Is used.

If the supply to the main motor is temporarily stopped, the copying process due to a deadlock or the absence of copy paper

interrupt, the reset state can be maintained, since the copy signal CPS is still received remain. The preset number of copies can be retained even if the user is in the course of the Copier desires, preferably or in between

make a copy of a special sheet of paper, and the counter remains reset because the copy signal CPS does not work in the case described above

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is deleted or terminated. After elimination of the deadlock or release or termination of the copy signal However, CPS due to a clear key operation during the interruption of copier operation starts the The counter CNT counts and the aforementioned automatic shutdown occurs when the counter has finished counting.

In the device described above, the main switch is automatically switched off directly without using a relay. The process is therefore very reliable and can be achieved with inexpensive components. It should also be noted that the voltage supply for the control coil or winding 151 of the main switch is automatically switched off after the automatic shutdown has been achieved, in order to avoid the development of heat in the winding. A signal representing a malfunction such as a deadlock clears the copy signal CPS, so that the counting operation of the counter or timer CNT starts. During such an interruption, the operation or activation of the 30-second timer for resetting the 7-segment display 45 to its original display "1" is prevented so that it continues to display the number displayed before the interruption. By a. Removing the deadlock will restart the timer.

A circuit shown in Figure 5 is used to energize the winding for the forced opening of the main switch when an increase in the supply voltage is detected; it contains a rectifier circuit Rec2, fault detector resistors R. and R ₂ »a constant diode Q104 or a diode with constant voltage drop as a standard voltage source, a comparator Q103 and an OR gate Q102.

A circuit shown in Fig. 6 is used to energize the winding for the forced opening of the

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Main switch when the temperature of the fixing rollers rises is determined; it includes a thermistor positioned close to or in contact with the first roller for detecting the temperature of the fixing roller shown in Fig. 1 and a control circuit TC for controlling the arranged in the fixing roller heater to a predetermined temperature level.

According to the invention, a desired goal or a monitoring desired IQ can be achieved in that the Circuit X shown in Fig. 3 is replaced by the circuit shown in Fig. 5 or 6. Furthermore, the This considerably reduces the safety area of the device. be improved that all components to be determined or the necessary circuits are connected to the OR gate Q102.

Reference is made to FIG. 5 below. If the source voltage rises above a predetermined voltage level on, it is determined via the comparator Q103 that the partial voltage generated via the resistors R. and R. is greater than the voltage at the diode Q104 and output power to the OR gate Q1O2 to the Main switch 152 forcibly switched off. Does not take up the voltage again after switching off the main switch at its normal value, the main switch remains switched off even when it is switched on. Relieves the tension returns to its normal value, the main switch can be switched on again. When the stabilizer circuit CV can change over a controllable stabilization range, the circuit can thus be protected and thus become safer.

Reference is made to FIG. 6 below. Since the thermistor 200 is near the lamp 5 or the platen 1 is arranged from glass, 'can the temperature caused by the heat generated by the lamp the platen and the glass in front of an even-

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tual breakage can be protected by the main switch is opened. ..

A circuit shown in FIG. 7 and differing from the circuit shown in FIG. 3 is constructed in such a way that the voltage source (V.) for the central unit CPU is not via the main switch 39 due to the arrangement made, so that the active state of the Central processing unit CPU is retained regardless of the switch-off position of the main switch. Therefore, the measurement or display of, for example, an interruption in operation of the device can also take place during an interruption of the copying process and the resumption of the operation can be carried out more smoothly. DSW denotes a door switch for switching off the device when a side panel is opened and switches off the voltage source provided in the device when a jam is removed. Although it is dangerous that the door switch DSW between the high-voltage transformer HVT and a device LVT _? arranged

it can only be used to switch off the power supply.

Fig. 8 shows a detailed sectional view of the

in Figs. 3 and 5 to 7 shown typical main

switch 39. The main switch or the power switching unit 39 is in the off state and the The device is switched on by actuating a hand lever 201 in the direction of the arrow. A ring 221 rotates upon actuation of the hand lever 201 ,. becomes a contact 217

actuated due to the rotation of the ring 221, and a contact 218 is used to switch through the voltage supply on contact with the contact 217. In addition, the main switch 39 contains a first coil 207 (151), a second Coil 208 (150), a movable core 209 and an armature 204. If the hand lever 201 is moved in the direction of the arrow, thus, the core 209 moves due to the driving current of the coil 207 and the overcurrent of the coil 208 up. This increases the inductance and

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likewise the excitatory force caused by the coils. The armature 204 is attracted and drifts in the process the ring 221 and the contact 217 in a direction opposite to the direction of the arrow. Accordingly, will the hand lever 201 is brought back to the position shown and the AC power line is switched off or interrupted. Since due to the interruption of the power supply via the AC voltage line no Current flows through a control terminal Y, the excitation of the coils 207 and 208 decreases and the armature 204 reverses

back to the position shown. This avoids overheating of the coils and you can continue to do so

the contacts 217 and 218 are activated independently of the armature when the hand lever 201 is actuated. The hand lever 201 can also be designed as a push button lever be.

In summary, there is provided a copier which has a processing unit for forming an image on a copy material, a process controller for operationally controlling the processing unit, a Manual power switch unit for supplying power to electrical loads in the processing unit and the process control, which one handle to the upright- ■ "* <> 25 obtained an on-state during a time interval from the start of manual power-on until the manual shut-off is activated and a coil to cancel the switched-on state of the hand lever before manual shutdown, and a

Has power control device for controlling the coil to the hand lever after a predetermined Time interval after the end of a copy process from the switched-on state to the switched-off state to bring, wherein the power control device a

by the process control for energizing the coil

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1 controlled timer.

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Claims (15)

Claims 15 20 30 1. Copier, characterized by a processing device (2 to 8, 18 to 20, 90) for generating an image on a copy material, a sequence control device (CPU) for controlling the Processing device (2 to 8, 18 to 20, 90), a manually operable power switching device (39) for applying voltage to electrical loads of the processing device (2 to 8, 18 to 20, 90) 'and the sequence control device (CPU), wherein
the power switching device (39) a manual switch (152), by means of which the switched-on state can be maintained from the time of manual switching on until manual switching off, and a coil (150,
151) for releasing the switched-on position of the manual switch (152) prior to manual switching-off, and a power control device (CPU, CNT) for exciting the coil (150, 151) for disengaging the manual switch (152) from the switched-on to the switched-off state after a predetermined time interval has elapsed
after completing a copy process, whereby the
Power control device (CPU, CNT) contains a timer device (CNT) controlled by the sequence control device (CPU) for exciting the coil (151). 35 130039/1012 Ro / rs - 2 - DE 093 2. Copier according to claim 1, characterized in that the timer device (CPU, CNT) during an interruption of the copy operation cannot be activated. 3. Copier according to claim 1 or 2, characterized in that the sequence control device (CPU) a Having clock pulse generating device and that the timer device is provided by the clock pulse generating device generated clock pulses for driving the coil (151) counts. 4. Copier according to one of claims 1 to 3, * characterized in that the power switching device (39) in addition a second coil (150) for automatically switching off the manual switch (152) when a having overcurrent flowing through the second coil (150). 5. Image forming apparatus characterized by a processing device (2 to 8, 18 to 20, 90) for generating an image on a copy material, a sequence control device (CPU) for controlling the Processing device (2 to 8, 18 to 20, 90), with a microcomputer (COM) for a time control for the processing device (2 to 8, 18 to 20, 90), a manually operated circuit breaker unit (39) for applying voltage to electrical consumers of the processing device (2 to 8, 18 to 20, 90), where- ™ with the power switching unit (39) a manual Actuation responsive means (152) and first and second solenoids (151 and 150, respectively) for releasing the device responsive to manual actuation (152), wherein the second coil (150) for overcurrent responds in the AC voltage supply line, and a power control device (CPU, CNT) to the 130039/1012 - 3 - DE 0932 'Device responsive to manual actuation (152) turn off automatically after copying is completed or a malfunction occurs. 6. Image forming apparatus according to claim 5, characterized in that the power supply for the Microcomputer (COM) is independent of a control of the coils (150, 151). 7. copier, characterized by a processing device (2 to 8, 18 to 20, 90) for generating an image on a copy material, a sequence control device (CPU) for controlling the • processing device (2 to 8, 18 to 20, 90), a manually operated power switching device (39) for applying voltage to electrical consumers the processing device (2 to 8, 18 to 20, 90) and the sequence control device (CPU), wherein the power switching device (39) a manual switch 2 "(152), by means of which the switch-on state differs from the point in time of manual switch-on can be maintained until manual switch-off, and a coil (151) for releasing the switched-on position of the manual switch (152) prior to manual switching-off, and a power control device (CPU, CNT) for energizing the coil (151) for a release of the manual switch (152) from the switched-on to the switched-off state upon detection of a malfunction occurring in the device. 8. A copier according to claim 7, characterized in that the malfunction is caused by an abnormal increase the temperature in an exposure device (1, 3) or a fixing heater is caused. 130039/1012 - "- - ■ ----- -" ■ - 30A9321 - 4 - ■ DE 0932 ] 9. Copier according to Claim 7 or 8, characterized in that that the power switching unit (39) has a second coil (150) for automatically switching off the Hand switch (152) when an overcurrent flows through 5 has the second coil (150). 130039/1012