JPS627548B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fixing device in an electrophotographic copying machine, and more particularly to a device for heating and fixing toner of a partially fixed image.

In general, an electrophotographic copying machine forms an electrostatic latent image on a photoreceptor by charging and exposing it to light, attaches toner to this latent image to make it visible, and then transfers the toner image to another transfer paper. The image is fixed as a permanent image through a post-heating device to form a reproduced image. The heating device, a so-called fixing device, has a heat source for heating and fixing the toner image. Therefore, the heating device is controlled to a fixable temperature for heating and fixing the toner using a heat source. That is, the temperature is controlled within a temperature range in which the transferred transfer paper does not catch fire and the toner is fixed.

Therefore, if the temperature has not reached the temperature at which it will be fixed,
The copying device itself does not become ready for copying, but waits until a predetermined temperature range is reached. In this case, the copying apparatus does not become ready for copying immediately by turning on the power due to the above-mentioned fixing device. You need to wait a few minutes. Therefore, in order to keep the copying machine always in the ready state, it is often left on without turning off the power.
This eliminates the need to turn on the power and wait several minutes before each copy. However, if the copying device is left as it is when no copies are being made, the power consumption of the fixing device will be extremely wasteful.

In view of the above-mentioned points, the present invention is designed to set the copying machine to the copyable state after the power is turned on, and to set the fixing device to the plate state after a certain predetermined period of time has elapsed without copying. That is, when the copying machine is in a ready state, a timer is activated, and after the timer period has elapsed, the power applied to the fixing device is limited to avoid wasting power. For example, when a large number of heat sources are used, several of them are opened to preheat the fixing device, that is, the fixing device is placed in a preheat state. This eliminates wasteful power consumption, and since preheating is performed, the time required to transition from the preheat state to the ready state can be extremely shortened.

The present invention will be explained in detail below with reference to the drawings.

FIG. 1 is a diagram showing the overall configuration of a copying machine according to the present invention. In the figure, 1 is a rotating drum that is rotated at a constant speed in the direction of the arrow around an axis 2.
The drum 1 has a master paper on its outer circumferential surface, that is,
A photoreceptor 3 whose front surface is made of a photoconductor and whose back surface is made of a conductive layer is removably mounted. Although not shown, the photoreceptor 3 is fixed to the outer circumferential surface of the drum 1 by being held down by a presser claw attached to the circumferential surface of the rotating drum 1 at its leading end. Also, when converting the photoreceptor 3, the presser claw opens, the old photoreceptor is conveyed to the outside, that is, to the paper outlet 5, and a new photoreceptor 3 is inserted from the photoreceptor insertion port 4, and its tip is inserted into the presser claw. It is held down and fixed. This operation is automatically performed in conjunction with the rotation of the drum 1. A micro switch MS ₇ installed near the photoconductor insertion slot 4 detects when the photoconductor 3 is inserted.
When the switch MS ₇ is turned on, the process moves to a replacement cycle for the photoreceptor 3, as will be explained later, and replacement of the photoreceptor is executed. The automatic replacement of the photoreceptor 3 is carried out by a known mechanism that has been developed in the past for this type of apparatus, and therefore a description thereof will be omitted. Various devices are provided near the rotating drum 1 to form an image corresponding to a document on the surface of the photoreceptor 3. In the figure, reference numeral 6 denotes a charger for uniformly charging the surface of the photoreceptor 3. The charger 6 generates a high voltage by energizing a charging high voltage generating unit CHVU as shown in the circuit diagram of FIG. 2, and the surface of the photoreceptor 3 is uniformly charged by this high voltage. The energization at this time is carried out by energizing the charging relay and closing its contact CHVR-a.

Reference numeral 7 denotes an exposure section, which irradiates the charged photoreceptor 3 with a light image to form an electrostatic latent image. This exposure is performed by illuminating the transparent glass surface of the document table 8 on which the copy document is placed using an illumination device 9, and transmitting the reflected light through an optical system 10.

Here, the document table 8 is configured to move in synchronization with the rotating drum 1. That is, the movement of the original platen 8 is started at the same time as the photoreceptor of the rotating drum 1 comes to the exposure section 7, and the moving speed at this time is naturally equal to the rotational speed (peripheral speed of the drum 1).

Reference numeral 11 denotes a developing device for visualizing the electrostatic latent image, and forms a toner image by adhering toner to the area where the electrostatic latent image is formed.

Reference numeral 12 denotes a transfer charger for transferring the toner image onto the transfer paper 13. The transfer paper 13 is automatically fed by a paper feed roller 20, and the first roller 2
1, the paper is conveyed into the copying machine, and is fed through each roller in synchronization with the rotation of the rotating drum 1. Once the paper is fed, it is stopped by a paper stopper 14 provided at the paper input section. will be stopped. The micro switch MS ₁ installed in the paper input section detects the paper input state, and when the rotating drum 1 rotates to a certain position while the micro switch MS ₁ detects paper input, The stopper 14 opens and the transfer paper 13 is fed, synchronized with the rotating drum 1 at a good timing, and brought into close contact with the photoreceptor 3 on which the toner image has been formed. The toner image is then charged by a transfer charger 12 and transferred onto a transfer paper 13. or,
Reference numeral 15 denotes a device for peeling off the transfer paper 13 from which the toner image has been transferred and which has been brought into close contact with the photoreceptor 3 of the drum 1 .

When the transfer paper 13 is peeled off from the photoreceptor 3, it is attracted to a conveyor belt 15a by an air suction force (direction indicated by an arrow) in a peeling device 15 and sent to the next process. A micro switch MS ₂ provided near the peeling device 15 detects when the transfer paper 13 is peeled off.

The toner image transferred to the transfer paper 13 is also in an unstable state and is not completely fixed on the transfer paper 13, so that it is necessary to fix the toner. This means that the transfer paper 13 is transferred to the conveyor belt 15 of the peeling device 15.
a, and sent to the fixing device 16, where the toner image is fixed.

The toner fixing device 16 is provided with three heater lamps HL serving as heat sources, and thermal fixing is performed using these heat sources. Further, there is an optimum temperature range for toner fixing in the fixing device 16, and a copying operation will not be performed unless this temperature is reached. The above temperature is about 300°C. Further, the transfer paper holder 17 of the fixing device 16 is at the position shown by the solid line when the power is turned on, and at the position shown by the dotted line when the power is turned on.
The micro switch _MS8 detects this state. The reason why this pedestal 17 is moved as shown by the dotted line when power is no longer supplied is because, for example, when a jam occurs in the transfer paper in the fixing device 16, the power supply section is opened, and at this time, the transfer paper 13 in the fixing section 16 is moved. The transfer paper 13 is placed further away from the heater lamp HL to prevent ignition, etc., and also to facilitate the removal of the transfer paper 13.

Transfer paper 13 conveyed within the fixing device 16
is carried out from the paper outlet 5 by the rotation of the feed roller 22. A micro switch MS ₃ installed near the paper output port 5 detects this paper output. Furthermore, 2
3 is for detecting the slip roller jam, and has a roller 23a as a driving roller and a roller 23b as a driven roller.
If the paper is being transported normally, the rotation of the drive roller 23a is transmitted, but the paper is not being transported normally. For example, if a jam occurs, rotation is not transmitted, and the jam is detected.

On the other hand, the reference numeral 18 in the figure is a static eliminator for removing static electricity from the transfer paper 13, and unlike the other chargers 6 and 12, the static electricity removal is performed by AC corona discharge. Also, although the photoreceptor 3 is not shown in the figure, the heater lamp HL
The charge is removed by the light beam from the cleaner brush 19.
The surface is cleaned and prepared for the next electrostatic latent image formation.

Here, the static eliminator 18 and the transfer charger 1
In both cases, when the high voltage generating unit THVU is energized, static electricity is removed by corona discharge and charging for transfer is performed.
The THVU is energized when the relay is turned on by a control signal from the control circuit and its contact THVR-a is closed.

Further, the document table 8 starts to move (feed) in synchronization with the movement of the rotary drum 1 to reach a predetermined rotational position, and returns to the original position when the movement exceeds a predetermined length (hereinafter referred to as overrun). controlled. Therefore, the initial stop position of the document table 8 is detected by the micro switch MS ₄ , which is provided opposite the actuating piece 8a that is interlocked with the movement of the document table 8, and the overrun of the document table 8 is detected by the micro switch MS4. Micro switch installed opposite to switch MS _4
MS5 .

FIG. 3 is a block diagram showing a circuit configuration for controlling each copying process shown in FIG. 1. In the figure, 30 is a microprocessor (hereinafter referred to as a control element) consisting of, for example, one chip and one package, and a control signal from this control element 30 controls a driver circuit 32.
energizes solenoids, relays, etc. involved in copying operations through the For example, drum feed clutch
When the DFC is turned ON, the rotating drum 1 starts rotating. Also, when the heater lamp relay HLR is turned ON, the contact HLR-a of the relay closes, and the heater lamp HL ₁
Electric power is supplied to the fixing device 16 to help speed up the temperature rise of the fixing device 16. In order to control these various solenoids, relays, etc., a synchronization signal 33 of the copying operation accompanying the rotation of the drum 1 is sent to the control element 3.
0, and the synchronizing signal 33 is used to derive a signal 35 (hereinafter referred to as a strobe signal) from the control element 30 that confirms the detection state of the microswitch group 34 that detects the various copying operations described in FIG. By applying this strobe signal 35 to a group of switches, etc., and inputting its output to the control element 30, the current state of each microswitch can be confirmed. Confirmation status at this time and the above synchronization signal 33
In combination, the control signal 31 as described above is output from the control element 30 to control copying of the copying machine.

The synchronizing signal 33 input to the control element 30 is generated by a signal generating section 37 as the rotary drum 1 rotates. In other words, the synchronizing signal generating section 37 is formed by forming a slit Pa on the outer periphery of a disc 24 shown in FIG.
A slit Pb is provided in the inner circumferential portion of the light emitting device, and a photoelectric conversion device consisting of a light emitting element and a light emitting element are respectively arranged through the slit. Therefore, a signal 35 synchronized with the rotation of the drum 1 is output from the synchronization signal generator 37. The position indicated by the arrow in FIG. 4 is the initial stop position of the rotating drum 1. or,
In this state, a synchronizing signal is obtained via the slits Pa-0 and Pb-1. In addition, 38 in the figure is the control element 30.
The control element 30 is set to the initial state when the power of the copying machine is turned on.

39 is a part that controls the temperature in the fixing device 16, and is a WTL level control circuit that keeps the temperature constant by controlling two heater lamps HL ₂ and HL ₃ . The output from this circuit is input to the control element 30, but if the output from the circuit 39 is a logical value "1", the temperature of the fixing device 16 has reached the specified value, and if the logical value is "0", the temperature of the fixing device 16 has reached the specified value. It is configured to be inputted to the control element 30 as being below a specified value. Here, the WTL level control circuit 39 controls power supply to the heater lamp HL based on a signal from the control element 30.
That is, power control of the heater lamp HL for setting the preheat state in the present invention is performed.

Furthermore, 40 is a circuit for detecting the slack propeller jam. That is, if an abnormality occurs in the operation of the roller 23 explained in FIG. 1, it is detected and the control element 3
The signal of that state is input to 0. In short, if an abnormality occurs in the operation, it is detected and a signal indicating the state is input to the control element 30. In short, if the logic value is "1", it is a signal that detects a jam state, and if the logic value is "0"
If so, it is a signal that is operating normally.

Next, the internal structure of the control element 30 will be briefly explained with reference to FIG. The control element 30 has a read/only/memory section 41 (hereinafter referred to as
(referred to as ROM), read and write leads,
It consists of a write memory section 50 (hereinafter referred to as RAM), an accumulator section for arithmetic control, an input/output section, a clock generation section for timing, and a power input section. FIG. 5 is a block diagram showing the internal structure of the control element 30, and the ROM 41 has an output 8
It memorizes instructions consisting of bit parallel signals _I1 to _I8 , and consists of pages _P0 to _P13 , with 64 words (steps) as one division.

That is, various instructions necessary for controlling the copying machine including the fixing device 16 in the present invention are stored in the ROM 41, and the stored instructions are sequentially read out to form the read instructions. Signal I ₁ ~ _{I 8}
will be explained later, but in addition to inputting it into each control circuit,
A signal such as a control signal is derived to the outside of the control element 30 through logic processing of this control circuit.

To explain in more detail, the control section of the ROM 41 has a 6-bit counter PL for addressing an arbitrary step on each page, and this counter PL is used to output jump command instructions from the ROM. Other than that, the count-up is done one step at a time. It also has a 4-bit counter Pu for addressing any page from page _P0 to page _P13 . This counter Pu differs from the above-mentioned counter PL in that the contents of the counter change at the time of a jump instruction. counter
The address signal from the PL is passed through the decoder 42 to address an arbitrary step in the ROM 41, so that the ROM 41 outputs all instructions for the same step from page _P0 to page _P13 . The signal is input to the gate circuit 43. This gate circuit 43 receives a signal from a counter Pu that addresses a page via a decoder 45, and outputs code signals _I1 to _I8 of an arbitrary page instruction. This output instruction code signal I ₁
~ _I8 is transferred to the instruction matrix ROM 44 which decodes the instruction. This instruction matrix ROM4
4 outputs micro-order, which is a feature of the microprocessor and serves as an input condition for the logic circuit of each control section.

The above counters PL and Pu will be counted up by one after the instruction is executed, and the counter Pu will be maintained in the same state, except when jumping to an arbitrary step by an instruction. Instructions written in the ROM 41 are read out. On the other hand, it has stack registers SL and Su, which have the same bit configuration as counters PL and Pu. That is, when the instruction indicating the jump command is read from the ROM 41, the contents of the currently executing counter PL incremented by one are stored in the stack register SL, and the contents of the counter Pu are stored in the stack register as they are. Memorized by Su. Then, change the jump destination from the jump instruction to the counter PL,
In this state, the instructions are executed as described above, and the contents of the counter PL are sequentially counted up and the instructions are sequentially read out. After that, when the instruction to return to the original state from the jump destination is read out from the ROM 41, the contents of the stack registers SL and Su are transferred to the counters PL and Pu, and one step from the step from which the jump instruction was read out,
Return to count up state.

The above is an overview of the ROM 41.

Next, the RAM 50 within the control element 30 will be explained. The control section of the RAM 50 has a 4-bit counter BL for addressing arbitrary words (steps), similar to the ROM, and the count contents of this counter BL can be changed by instructions. There is. However, if the instruction does not change the contents of the counter BL, the counter BL always retains its contents. Also, RAM50 block 0~
It has a 2-bit counter Bu that addresses any block of 3, and like the counter BL, it has a ROM
The instructions read from 41 maintain the contents of the counter Bu except for those that change the contents.

The output of the counter BL is input to the decoder 51, and the output of the decoder 51 addresses an arbitrary word in blocks 0 to 3 of the same step of the RAM 50, and the addressed arbitrary word is input to the gate circuit 51.
Input/output is possible via 3. Also, counter Bu
The output is input to the decoder 54, and the decoded output enables the gate section of the gate circuit 53 of any selected block among blocks 0 to 3 of the RAM 50. Therefore, any step in one block of RAM 50 can be input/output by the outputs of counters BL and Bu.

Further, input/output signals are input/output in 4-bit parallel form via the gate circuit 53. That is, the input signal
The contents of M ₁ I to M ₄ I are stored in any step addressed by the counter BL in any block addressed by the counter Bu. Contrary to the above, the output signals M ₁₀ to _{M 400} are output signals of the contents stored at any step in any block.

Here, the clock signal from the clock generator 60 is
C ₁ , C ₂ , C ₃ are output, and the above input signal M ₁ I
~ _M4I is RAM5 at the timing of clock signal _C1 .
0 can be input, and its contents are stored.Meanwhile, the contents stored in the RAM 50 are outputted as output signals _M10 to _M40 via the gate circuit 53 at the timing of the clock signal _C3 . Furthermore, ROM41
Although not described in the above section, the instruction reading from the ROM 41 is performed at the timing of the clock signal _C1 , and the time required to read the next step instruction is approximately 10 minutes.
It is μsec.

On the other hand, the decoder 51 addresses the RAM 50 and outputs a decoded output to the outside of the control element. This output signal is derived from the terminal S ₁ when the content of the counter BL is "15", the terminal S ₂ when the content is "14", the terminal S ₃ when the content is "13", ... "9" A signal is derived from the signal terminal _S7 in this state. This output terminal
The signals S ₁ to _{S 7} are used as key strobe signals when the keys of the input section of an electronic computer are connected, for example, and in the present invention, as shown in FIG. It is used to check the operating status of the microswitch group and other switches.

On the other hand, regarding the input/output section, this input/output section is
It is controlled by instructions read from the ROM 41.

First, as shown in FIG. 7, the input section according to the present invention is an input section TAB, AK to which the strobe signal derived from the control element 30 described in FIG. 3 is inputted via the switch group according to the present invention. , KN ₂ ,
There are synchronization signal input sections α and β for synchronizing the copying machine controlled and driven by the control element 30. Signals from the synchronizing signal generator 3 obtained through slits Pa and Pb of a disc 24 provided on the same axis as the rotating drum 1 are inputted to the input parts α and β. The input section α receives the signal obtained from the slit Pa of the disk 24, and the input section β receives the signal obtained from the slit Pa of the disk 24.
A signal obtained from Pb is input.

Further, there is an input section _KN1 for inputting a signal from the WTL circuit 39, and an input section KF for inputting a signal from the slip roller jam detection circuit.

Furthermore, as explained in FIG. 3 as an input section, there is an ACL input section that performs initial settings when the power is turned on, and when a signal is input to this input section ACL, the flip-flops are reset and the ROM 41 is reset.
P ₁₃ page is now set.

On the other hand, as shown in FIG. 3, the output section includes registers F ₁ -F ₄ of 4-bit configuration and registers W ₁ -W ₁₅ of 15-bit configuration, which are output in parallel. The registers W ₁ to W ₁₅ are output when the flip-flop Np is set.

That is, in the present invention, various controls of the copying machine are performed by signals output in parallel from the registers _F1 to _F4 and registers _W1 to _W15 . Note that clock signals C ₁ to _{C 3} for operating each circuit in the control element 30
is output from a clock generator 60, and this clock generator 60 is executed by inputting a signal from an externally connected clock generating means 59 to a clock signal input section φ.

The control element 30 according to the present invention is constructed as described above, and its operation will be briefly described next.

First, when the power switch of the copying machine is turned on, the main switch MSW shown in the circuit diagram shown in FIG. 2 is closed, the main motor MM rotates, and the control element 30 is set to the initial state. Therefore, the control element 30 sequentially reads instructions from the ROM 41, causes the read instructions to output a micro order through the decoding ROM 44, controls the opening and closing of each gate group using this micro order, and controls the read instructions. Processes the traction code and sends the control signal 31 to the driver circuit 3
2. For example, drum feed clutch
Turn on the DFC and rotate the rotary drum 1. This causes the drum 1 to rotate in order to set it to its initial state. Due to this rotation of the rotary drum 1, synchronization signals PA and PB are input to the input terminal αβ of the control element 30. Control element 30 derives control signals for executing various copying operations according to the synchronization signal. Furthermore, when the power is turned on, the heater lamps HL ₂ and HL ₃
is lit and is controlled by the WTL level controller circuit 39. In this case, the heater lamp
When the fixing temperature is reached by HL ₂ and HL ₃ , WTL
The circuit 39 applies its signal to the control element 30. This causes the control element 30 to control the ready lamp.
Deriving the control signal to turn on the PL and pressing the print switch PSW. However, it is assumed that the rotating drum 1 is set to the initial state.

Therefore, when the print switch PSW is pressed, the rotary drum 1 rotates, and various mechanisms are operated by the control element 30 according to the operating state of each microswitch along with a signal synchronized with the rotation. Therefore, when the rotating drum 1 reaches a certain position, i.e., the synchronization signal
In accordance with the inputs to PA and PB, the light source lamp CL of the illumination device 9 is turned on, the surface of the photoreceptor 3 is charged by each charger, and the document table 8 starts to move. On the other hand, if the micro switch MS ₁ detects paper entry, the paper stopper 14 is activated in synchronization with the rotation of the drum 1.
is opened, and the transfer paper 13 is transported by the transport roller 21.

On the other hand, an electrostatic latent image is formed on the photoreceptor 3 in the exposure section 7, and this latent image becomes a toner image in the developing device 11 and is sent to the transfer section for the next step. The transfer paper 13 conveyed to the photoreceptor 3 is brought into close contact with the photoreceptor 3 in a well-timed manner, and the toner image is transferred onto the transfer paper 13 by the transfer charger 12. Thereafter, the transfer paper on which the toner image has been transferred is peeled off from the photoreceptor 3 of the drum 1, and in the peeling device 15, it is adsorbed to the conveyor belt 15a by air suction force, and the static electricity is removed by the static eliminator 18, and the heater lamp HL is installed. fixing device 16
transported to. Then, the transfer paper 13 is conveyed within the fixing device 16 and is conveyed to the outside from the paper output port 5 by a feed roller 22.

In the present invention, in the above-mentioned copying machine, if the copying machine is in the ready state, and the print switch PWS is not pressed for a certain period of time (2 minutes in this embodiment), the copying machine is set to the preheat state. The operation will be explained in detail below with reference to the flowchart of FIG. still,
FIG. 6 shows the ready state as well.

First, when the power is turned on and the initial state of the rotating drum 1 is set, the micro switch MS ₄ is first turned on in the flowchart of FIG. The control _element 30 outputs a strobe signal _S1 , and this signal is sent to the input section _KN2.
is input, and the above microswitch MS ₄ is judged as Yes. Therefore, I turned off the document table return solenoid TRS (turned it off from before), and turned off the slipper roller jamb SRJ and micro switch MS _2.
to make fun of. This guy is in any case
It is judged as NO. On the other hand, Micro Switch MS ₂
If it is operating in this state, it will be treated as a jam.

Next, PB is jagged, but this synchronization signal PB
Since this is the initial state of the rotating drum 1, it is naturally input to the input section β of the control element 30, and is determined as Yes. In addition, if it is judged as NO in the above PB direction, the drum feed clutch DFC is activated to find the initial position of the rotating drum 1 again.
is turned ON and the operation described above is performed.

After the above, change WTL, but here,
If the temperature in the fixing device 16 is above the specified value, WTL is judged as Yes, but if it is below the specified value, it is judged as NO and turns on the heater lamp relay HLR and then turns on the ready lamp RL.
It is turned off and the same operation described above is repeated. Then, when the temperature of the fixing device 16 rises and exceeds the specified value, a signal of "1" is input from the wait time level detection circuit 39 to the input section KN ₁ , so WTL is determined as Yes, and the heater lamp Relay HLR is turned off. After that, microswitch MS ₄ is judged as Yes and TRS,
CHVR, THVR, and CLR are turned off. Here, CLR is a relay for the light source lamp of the lighting device, and when the relay is turned on, the lamp CL (second
(see figure) lights up, illuminating the document table 8.

As the next operation, the preheat PH is adjusted. This preheating means that the temperature of the fixing device 16, which is powered on, is maintained at a relatively low steady state. That is, when adjusting the PH, the strobe signal is sent to the terminal S ₅ as shown in Figure 7.
This is done by determining that the signal is output from the input terminal AK of the control element 30 through the diode DPH.

As mentioned earlier, the preheat PH is provided because, for example, when a copier is turned on and left unattended, the heater lamp in the fixing section
HL is lit and there is no brim, which is a waste of electricity. Therefore, in order to perform the preheating PH as described above, the diode DPH is connected as shown in FIG. 7, and the auto preheating state is set after, for example, two minutes have elapsed from the time when the PH is changed. In other words, in this state, the heater lamp
The power supply to the HL is controlled to reduce power consumption. Also, the PH lamp indicating the preheat state is turned on to notify that the preheat state is present.

To explain the above in detail, by confirming that the strobe signal is input to the input terminal AK in the PH jack, if it is judged as Yes, it will be judged as NO in the Test jack, and then the 2-minute timer circuit will start. It is formed. The two minute timer is formed within the control element 30. As mentioned above, the time from when an instruction is read to when that instruction is executed and when the next instruction is read is approximately 10 μsec. This is achieved by counting the number of times instructions are executed.

Next, a 2-minute timer is checked, and this check is determined as Yes after 2 minutes have elapsed.
Therefore, if printing is performed from the time the power is turned on and the printer is left unattended, the fixing device 16 is automatically set to the preheat state after two minutes have elapsed. At this time,
The 2 minute timer is reset and the heater lamp relay
HLR ON, ready lamp OFF, preheat
PH is turned on. Above heater lamp relay HLO
The heater lamp, which is a backup heater, is turned on when
HL ₁ is lit, while the above preheat PH
By turning ON, the heater lamps HL ₂ and HL ₃ are turned off under the control of the WTL circuit 39, although not shown in the figure.

Next, the micro switch MS ₄ is switched on.
Determined as Yes. Also, since drum 1 is in the initial state, the PB jack is judged as Yes, and the next slip roller jamb SRJ is jacked, and the micro switch MS ₂ and print switch are turned on.
PSW is judged and both are judged as NO. This causes the microswitch to be turned on again and the same operation can be repeated. In short, it was set to a preheat state. In addition, the print switch PSW doubles as a switch for canceling the preheat state and a switch for printing.
Press PSW to cancel the preheat state,
Ready status is indicated. On the other hand, pressing PSW in the ready state enters the print cycle.
In other words, the print switch PSW is activated in the preheated state.
When is pressed, it is judged as Yes by the PSW, the preheat is turned off, the lamp that was informing the preheat state goes out, and the heater lamps HL ₂ and HL ₃ are turned on. The G flip-flop is flipped and the F flip-flop is set to return the copying machine to its initial state.

As described above, when the copying machine is left unattended, after two minutes it enters the preheating state and power consumption is reduced.

On the other hand, before entering the preheat, that is, if the 2-minute timer is determined to be NO, the 2-minute timer is started. If the F flip-flop is jacked but is in the preheat state and is jacked after the preheat state is canceled, it is judged as Yes, but here, it is judged as NO.
We will explain the case where it is determined that Therefore, the micro switch _MS7 is changed, the ready lamp RL is turned on, and the print switch PSW is changed. This print switch
The PSW also outputs a strobe signal from terminal _S3 to check whether it is ON or OFF. Here, if the print switch PSW is determined to be NO, the F flip-flop is reset and the same operation is repeated again. This indicates a so-called ready state, and a ready lamp RL indicating this is lit. In addition, in this state, the reason why the print switch PSW is being adjusted twice in a row is because the print switch PSW is
This switch is used to distinguish between preheat release and copy cycle execution. That is, after canceling the preheat, set the F flip-flop so that the first PSW jump will not be judged as Yes, and pass the above through the F flip-flop jump.
Prevents PSWs from being teased. In the so-called preheat state, the print switch
At the same time as pressing PSW and preheating is canceled,
It prevents entering the copy cycle. Here, even if the copy cycle starts at the same time, the fixing device 1
If the temperature of 6 is above the specified value, the ready lamp
RL is lit and there is no problem, but if it is lower than that, it will be determined as NO in the WTL jersey and an operation to turn off the ready lamp RL will be executed, and even if you press the print switch PSW, this PSW will not be confirmed. No signal is output and the copy cycle does not start.

As explained above, according to the fixing device of the copying machine of the present invention, the copying operation is performed within a certain period of time from the time when the copying machine can be used, such as when the power is turned on and a series of copying operations are completed. If the copying machine is left unattended, the fixing device, etc. will not start because it is set to a preheat state, in which case the heating and fixing device will be driven with lower power consumption than normal power consumption. The power consumed can be reduced as much as possible. In addition, since the heating and fixing device is set to a preheat state without having to stop all operations of the copying machine, it is possible to effectively prevent the temperature of the preheated fixing device from decreasing. The time can be reduced as much as possible, and the use and operation of the copying machine becomes more convenient.

[Brief explanation of the drawing]

FIG. 1 is a sectional view for explaining the structure of a copying machine according to the present invention, FIG. 2 is a circuit diagram of a power supply section according to the present invention, FIG. 3 is a control block diagram of the copying machine according to the present invention, and FIG. 4 FIG. 5 is a block diagram showing the configuration of the control element according to the present invention, and FIG. 6 explains the operation of the fixing section of the present invention. FIG. 7 is a block diagram showing the input/output terminals of the control element. 1: Rotating drum, 16: Fixing device, 30: Control element, 31: Control signal, 32: Driver circuit,
39: WTL level controller circuit, HL ₁ ~
HL ₃ : Heater lamp, PH: Preheat lamp,
RL: Ready lamp, HLR: Heater lamp relay.

Claims (1)

[Claims] 1. A heat source control means for controlling a heat source in response to power-on of the copying machine and controlling the temperature at which the fixing device itself can be fixed; A fixing device for a copying machine, comprising a preheating means for driving the heating source with lower power consumption than normal when a copying operation does not start within a certain period of time from a standby state.