JPS60149055A - Image forming device - Google Patents

Abstract

PURPOSE:To permit easy treatment after generation of a paper jam by making display different according to the position where the paper jam arises. CONSTITUTION:When a switch SW5 fails to detect paper at a prescribed timing as a result of a jam generated near rollers 29, 30, 36, a non-detection signal is inputted to a control circuit which outputs a jam signal to light a display device 204, thus opening a door 202 and indicating a jam treatment. When the switch SW5 fails to detect the paper at the 2nd prescribed timing in the case of the jam near a fixing device, a jam signal is outputted to the control circuit which lights a display device 205 and opens a door 201 thus indicating the removal of the jammed paper. When the operator opens the door, a switch SW2 of 3 is turned off, by which conduction of electricity to AC loads such as a motor for driving a conveying roller, fixing heater, high-voltage transformer, etc. is interrupted. The DC power source to the control circuit is changed over to a line independent of the system for the door switch and main switch upon generation of the jam signal and therefore the control circuit is in the operating state even during the jam treatment for removing the paper and permits smooth copying operation in succession.

Description

[Detailed description of the invention] The present invention relates to an image forming apparatus such as a copying machine.

Conventionally, when a jam problem such as a paper jam occurs in a copying machine, the operation of the copying machine and attached equipment such as a sorter used in conjunction with the copying machine is stopped. A switch installed on the side panel of the copying machine shut off all power to the copying machine.

However, in recent years, the setting and calculation of the number of copies to be repeated has come to be done electronically, so if a jam occurs in the middle of continuous copying and the side panel is opened, the set number of copies and copying method number will be cleared. This caused the inconvenience that subsequent copying could not be carried out smoothly.

The present invention eliminates the above-mentioned drawbacks, and makes subsequent processing easier by changing the display depending on the position of paper jam occurrence.

FIG. 1 is a sectional view of a copying apparatus according to the present invention.

The surface of the drum 11 is made of a three-layer photoreceptor using a CdS photoconductor, and is rotatably supported on a shaft 12.
Rotation in the direction of arrow 13 is started in response to the copy command.

When the tram 11 rotates to the normal position, the original platen glass l
The original placed on the mirror 41 is illuminated by an illumination lamp 16 integrated with the first scanning mirror 15, and the reflected light is
Scanning is performed by a first scanning mirror 15 and a second scanning mirror 17. The first scanning mirror 15 and the second scanning mirror 17 are l:1
By moving at a speed ratio of /2, the original is scanned while the optical path length in front of the lens 18 is always kept constant.

” - The reflective light layer passes through the lens 18, the third mirror 19, the fourth mirror 20, the exposure section 21, and the drum 11.
image on top.

The drum 11 is charged (for example, +) by a negative charger 22.
After that, in the exposure section 21, the image illuminated by the illumination lamp 16 is subjected to slit exposure.

At the same time, charge removal of the opposite polarity (for example -) to AC or - is performed by a charge eliminator '23, and then the entire surface is exposed by the full-surface exposure lamp 24 to form a high-contrast electrostatic latent image on the drum 11. The electrostatic latent image on the photosensitive drum 11 is then visualized as a toner image by the developing device 25.

Transfer paper 27- in cassette 26-■ or 26-2
1 or 27-2 is fed into the machine by the paper feed roller 28-1 or 28-2, and is fed into the machine by the feed roller 28-1 or 28-2.
1 or 29-2, accurate timing is determined by the second register roller 30, and the recording material is sent toward the photosensitive drum 11.

Next, the transfer paper 27 is passed between the transfer charger 31 and the drum 11.
The toner image of the drum 1l-J- is transferred onto the transfer paper while the drum 11-J- passes through the transfer paper.

After the transfer is completed, the transfer paper is guided to the conveyor belt 32, further guided to a pair of fixing rollers 33-1, 33-2, fixed by pressure and heat, and then discharged to the tray 34.

After the transfer, the surface of the drum 11 is cleaned by a cleaning device 35 composed of an elastic blade, and the process proceeds to the next cycle.

Here, if the transfer paper is skewed or twisted after being fed from the cassette, the roller 29-1°29-2.30.
The transfer paper may not fit into each of the transport rollers such as 36, and may become jammed near those rollers. In particular, if it gets caught in the fixing roller 4 and is not discharged, there is a risk of fire.

Therefore, in order to detect paper jams in the image transfer material, paper detection microswitches SW4 and SW are installed near the exit of the conveyance path.
5 is provided, and a jam is determined by detecting whether or not this detector is operating at a predetermined time, and if paper is not detected, a display warning is given as a jam. This check signal at a predetermined time is a timing signal programmed in advance in the process sequence control circuit.

FIG. 2 is a perspective view of the copying machine shown in FIG. 1.

Jam processing will be explained below.

In the figure, 201 is an opening/closing door for removing jammed paper near the fuser, 202 is an opening/closing door for removing jammed paper near each transport roller, 203 is a copy command operation panel, and 204 and 205 are used to remove jammed paper. SW1 is a switch for supplying alternating current to the copying machine, and SW2 and SW3 are door switches that turn off when each opening/closing door 201 and opening/closing door 202 are opened, and turn on when closed.
206 is a display that displays the number of copies manually made using the number key 20tB, and 207 is a display that displays the number of copies that have been made. The rest is the same as in FIG.

Now, when there is a jam near the rollers 29, 30, and 36 and the switch SW5 does not detect paper at a predetermined timing, a non-detection signal is input to the control circuit and a jam signal is output. This output lights up the display 204 to indicate that the door 202 should be opened to clear the jam. When the switch SW4 does not detect paper at a predetermined timing in the case of a jam near the fixing device 2, it similarly outputs a jam signal. This output lights up the display 205 to indicate that the door 201 should be opened to remove the jammed paper.

When the door 201 or 202 is opened, the switch SW2 or SW3 is turned off, thereby cutting off power to AC loads such as the drive motor of the conveying roller, the fixing heater, and the high voltage transformer.

However, when a jam signal occurs, the DC power supply to the control circuit is switched to a line independent from the thread path of the door switch and main switch. The set number of copies and the number of copies stored in , are stored without being canceled, and the respective numerical values continue to be displayed on the displays 206 and 20.7. Moreover, during and after jam removal, the door 201,
202, the number of jammed sheets is subtracted from the number of copies, and the display 207 displays the result.

Therefore, copying operations can be continued smoothly.

FIG. 3 shows an example of a control circuit for the above.

40 is a plug that takes in commercial voltage, and the main power line from plug 40 is door switch SW2.

It is connected to the C terminal of the microswitch 42 and the No terminal of the relay 50, which operate in conjunction with SW3. The other line of the plug 40 is also connected to the C terminal of a microswitch 44 which operates in conjunction with the door switches SW2 and SW3 and to a low voltage transformer 51. and micro switch 42
The NC terminal of is connected to the main switch 5W via the breaker 43.
II7) Connected to the C terminal of the B contact. The microswitch 41 operates in conjunction with the microswitches 42 and 44, its C terminal is connected to ground, its NC terminal is connected to the C terminal of the a contact of the main switch SW1, and the control circuit 58
It is connected to the. N of the b contact of the main switch SWI
The o terminal is connected to the primary side of a low voltage transformer 51 via a main motor 46 that drives the copying machine, loads such as a high voltage transformer 47, and contacts of a relay 50. Low voltage transformer 5
One terminal of the secondary coil No. 1 is connected to a control circuit DC power source 54 through a breaker 52, and the other terminal is similarly connected to a DC load power source 55 through a breaker 53.

Here, the motor 46 is connected to the photosensitive drum 11. It rotates the conveyance roller and fixing roller and moves the optical system 15.17, and the high voltage transformer 47 operates the conductors 22, 23.31. In addition, the image exposure lamp 16 is used as a load.
．． There is a full exposure lamp 24. Main motor, heater.

A control signal for the triac 48.62 for switching the transformer is received from the control circuit 58 at a predetermined timing. The DC power source 54,55 is a well-known regulated power source that rectifies and stabilizes alternating current. The control circuit, as shown in FIG. 4, is a well-known central program control circuit that outputs output in the direction of the arrow in response to a human input signal in the direction of the arrow and in response to an internal program memory. The jam counter 56 is a well-known mechanical counter that counts the number of jammed sheets each time a jam occurs, and the jam solenoid 57 connects the reset switch 59 to the No terminal when a jam occurs. The reset switch 59 is locked to the No side. In this case, even if the power is turned on after the jam is cleared and the copy button is turned on, the copying process will not start. The process is enabled by manually switching the switch 59 to the NC side.

A timer 60 maintains the direct current power to the control circuit 58 for five minutes after a jam, and cuts off the direct current power after five minutes have elapsed.

The relay 50 switches its contact to the No side when a jam is detected, thereby switching the power line to the transformer 51.

To briefly explain the control circuit in Fig. 4, the ROM
is a program memory in which the flow steps shown in Fig. 5 are preprogrammed in binary code, RAM is a data memory that stores program memory data and input signal data such as the number of copies, and INPUT is an input port for gate-in input signals. , 0UTPUT is an output port that latches the output signal, ACC is an accumulator that temporarily stores data from the input port and data sent to the output port, and a decoder that decodes the ROM code.

It has the function of an ALU that calculates and logically discriminates data from ROM, RAM, and input/output ports. Introductory capo
) A signal CPB which becomes 1 when the copy button is turned on, a signal JRES which becomes 1 when the jam reset switch 59 is reset to the NC side, are connected to terminals 1 to 4 of the A port of INPUT.
A signal CFS that becomes 1 when either the main switch or the door switch is turned off, and a signal TIM that becomes 1 when the 5-minute timer is turned on are input. When the switches SW4 and SW5 are on, a signal of 1 is input to the B boat terminals 1 and 2.

The jam detection signal JAM that activates the jam solenoid 57 and timer 60 and the signal JAMR that activates the jam counter 56 and jam relay 50 are sent from the 1st and 2nd terminals of the D boat of the output port 0UTPUT, and from the 1st to 4th terminals of the E boat,
A signal DMT for turning on the motor 46, a signal FIX for turning on the heater 61, a signal HVTE for turning on the high voltage transformer, and a signal PF for turning on the transfer sheet feeding start roller 28 are output.

In this control circuit 58, the input signal is taken into the ACC according to the program steps of the ROM, and when it is determined whether it is 1 or 0 and the branch point of the operation is determined, the process proceeds to the next step and latches a predetermined output port [1 The numbers 1 to 4 in C are input to data obtained by converting the signal from the numeric key 207 on the control panel into a 4-bit binary coded decimal format. .

Output ports 1 to 4 are well-known 7-segment number indicators 2
Same code as above to display number on 06.207 4
Those that output bit data, F port SJI, SJ
2 are each SW4.

This is for indicating a jam regarding SW5.

Input capo) B 3 manually inputs a timing signal that becomes 1 by turning on a switch operated by a cam installed on the drum.

4 inputs a switch-on signal operated by a cam provided in the optical system.

The operation from turning on the power switch SW1 will be explained with reference to FIG.

When the main switch SWI is turned on, the motor 46, heater 61 . High voltage transformer47. Power can be supplied to the AC circuit of the low voltage transformer 51.

The control circuit 58 is powered on by the output of the low voltage transformer 51, and the control circuit performs step 1 of the preparation cycle. In this cycle, all circuits are first reset, key entries are made, and a number display routine is performed.

That is, the data by the key is taken into the input port, and the RA
M g) is stored at address a, and its contents are displayed on the display 206 via the output port.

The program then proceeds to a routine that detects that the copy button is turned on. If the CPB is determined to be 1 in step 2, the process advances to step 3, a copy cycle execution step.

That is, first, the E port is latched and the motor signal DMT,
Output the heater signal FIX to each triac 48, 62
Turn on and energize the motor and heater high voltage transformer. When the drum rotates to a specified level, the signal C8 is generated by the cams 1" operation.
is input, a paper feed signal PF, an image exposure lamp ON signal, and an optical system forward movement signal are outputted, and paper feeding and exposure scanning are started. The clutch is for converting the rotational force of the motor into forward force. When the exposure is completed and the optical system reaches the reversal position, a reversal signal BSI is output and the circuit 58 receives it, turns off the lamp and clutch, and turns on the reverse clutch to move the optical system backward.

As the drum continues to rotate, a copy image is formed on the transfer paper through the development and transfer area, and the transfer paper is transported outside the machine. Thereafter, reading of the B boat is enabled at each time when the paper is passing through the switches SW4 and SW5. Then, the process proceeds to step 4, and when it is determined by SW4.5 that paper is detected, the process proceeds to step 5. The reading of the B port is performed by a routine programmed with a timer to check the paper after a predetermined time has elapsed from the reversed position.

If paper is detected, the process proceeds to step 5, where the remaining process operations such as turning off the high voltage transformer by input from the drum cam are performed again, and the process proceeds to step 6. Since the jam flag is O, it is determined and the process proceeds to step 7, where it is determined whether the number of copies is equal to the set number of sheets, and when they are equal, copying is completed, the main motor is turned off, and the process returns to step 1 again.

The jam flag here is at address J of the RAM where 1 was stored when the jam was detected.

If it is determined in step 4 that no paper is detected or a jam is detected, the output port D is latched in step 8 and a jam signal I is output.
, jam counter, and jam relay J are output, and a jam flag is set.

This turns on the jam solenoid 57 and switches the reset switch 59 to the NC side. Also, the relay 50 is operated to connect the primary side of the low voltage transformer to the plug line. Also, the counter 56 is incremented by 1.

Then, the process advances to step 9, where the number of sheets lost due to jamming is subtracted from the number of sheets copied so far when a large number of sheets are continuously copied.

Note that continuous copying proceeds from step 7 to step 3. Further, the number of copies is stored by incrementing the address b of the RAM by 1 every time the transfer paper feed signal is output in step 3. The subtracted number is also stored again at address b.

In step 5, the remaining copying cycles are performed as described above and the process proceeds to step 6. It is determined that the jam flag is 1 and the process proceeds to step IO.

In this step, a routine is performed to determine whether the main switch or the door switch is turned off. Since it is still on, perform the jam display routine in step 11, output SJI or SJ2 from the F boat,
As described above, the door for removing the paper is indicated depending on the location of the jam. Also, the set number of copies and the subtracted number of copies are displayed. When door 201 or 2o2 is opened, the door switch is turned off, so step 10 is exited. At this time A
Although the C circuit power is cut off, the DC power is maintained as described above. Therefore, there is no chance of getting one's hand caught in the conveyance system or getting an electric shock during jam processing, and the number of sheets being processed can continue to be displayed. Note that the display routine for the number of set sheets and the number of copied sheets is inserted in steps 1, 3, and 5.degree. 11, and is not specially illustrated.

In step 12, it is determined whether the reset switch 59 has been returned to the NC side. After removing the paper and returning the reset switch, the process proceeds to step 13, where it is determined whether the main switch and the door switch have been turned on. After turning on the reset switch, close the door and turn on the main switch to skip this step and proceed to step 14. Here, the previously set jam flag is reset and the output latches of jam signal I and jam relay signal J are released. . Therefore, the relay 50 returns to its normal state and the DC power supply path is switched to the AC circuit. Also, the jam solenoid 57 is reset.

Step 15 is to determine whether the number of sheets matches, similar to step 7, and if there is a match, the process returns to step 1. If continuous copying is in progress, the process advances to step 16 and waits for the copy button to be turned on. During this time, the display routine II of step 17 is executed to display the number of copies and the number of set sheets subtracted after the paper jam.

When the copy button is turned on, the process goes to step 3 again, and the remaining number of copies are made.

The jam counter 56 is used to store the cumulative number of paper jams, and is used as data for calculating fees and examining the reliability of the apparatus by service personnel. The step of also turning off the control DC power supply when the paper jam is not cleared for 5 minutes after opening the door after the jam occurs will be explained.

If the doors of both doors are not closed or the main switch is not turned on in step 13, the process proceeds to step 18, where the pulse signal TM is output and the timer 60 starts the timer operation. As long as the time is not up, the process proceeds to the display routine of step 11 and continues to display the number of sheets being processed for jamming.

If the reset switch is not turned on and all door switches are not turned on, the latch of the 5-minute diameter jam relay signal J is turned off, and the relay 50 is turned off, cutting off the low voltage transformer.

As a result, it is possible to stop supplying excess power for a while when a paper jam is being cleared.

Note that the present invention can also be applied to a copying machine with a movable document table and a recording device that prints out the output of an IT'll device.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of a copying apparatus applicable to the present invention, and FIG.
3 is a perspective view of FIG. 1, FIG. 3 is an example of a control circuit according to the present invention, FIG. 4 is a partial circuit diagram of FIG. 3, and FIG.
2 is a flowchart of the control steps in FIGS. 2 and 3. In FIGS. 2 and 3, SWI is a main switch, SW2 and SW3 are door switches, 50 is a power switching relay, and 6o is a timer.

Claims (1)

[Scope of Claims] An image forming apparatus that forms an image on a recording member, comprising: a detection means for detecting a conveyance failure of the recording member; a display means for displaying that the conveyance failure has occurred; An image forming apparatus comprising: a control means that changes a display accordingly; and a reset switch that makes it possible to restart an image forming operation regardless of the position where the conveyance failure occurs.