JPH01211775A - Waiting time display device for copying machine - Google Patents

Abstract

PURPOSE:To display a waiting time which has a small time lag with an actual fixing warming up time by using a corrected value in accordance with the variation of input voltage, calculating the waiting time based on a detected temperature and displaying it. CONSTITUTION:The input voltage is incorporated in a CPU 40 through an A/D conversion element 49 and an I/O element 45 and monitored. Several temperature rising rates are previously stored in a ROM 44, etc., according to the value of the input voltage and one of temperature rising rates is selected corresponding to the current input voltage monitored. The selected temperature rising rate is offered to calculate the waiting time and the calculated waiting time is displayed on a waiting time display part 57. After displaying the waiting time is decreased by '1' from the waiting time every minute and displaying time is shortened 1min by 1min. When it becomes at a fixing set temperature actually, the display is not performed and the title machine is in a copying possible state. Thus, the waiting time having small time lag with the actual warming up time can be displayed.

Description

TECHNICAL FIELD The present invention relates to a standby time display device for a copying machine using a heat fixing device.

Conventional technology In general, after the power is turned on in a copying machine, a standby display such as "Please wait" is displayed until the temperature of the fixing device reaches a set value, but this is inconvenient because it is difficult to know how long to wait. be. Furthermore, if the door is opened for jam removal, etc. after the temperature of the fixing device reaches the set value, the fixing device will not be cold started after that, so it should reach the set temperature in a short time. However, I don't know how long it will take or how long I should wait.

For this reason, for example, according to Japanese Unexamined Patent Publication No. 57-64272, there is a system in which the temperature of the fixing device is displayed using a copy number display field on the operation panel. However, even if the temperature of the fixing device is indicated, it is difficult to determine how long the standby time will be.

Further, according to Japanese Patent Application Laid-Open No. 57-198479, the temperature of a fixing roller in a fixing device is detected by a thermistor,
Based on the data corresponding to the fixing port temperature obtained by A/D converting the change in resistance value, the waiting time until the fixing device reaches the fixing temperature is calculated, and the obtained waiting time is manipulated. What is displayed using a part of the panel, etc. is shown. According to this, it becomes easy for the operator to understand how long the operator should wait before copying can be performed.

However, when such a standby time calculation method is used, there is a large error when the input voltage to the heater fluctuates. Specifically, it is thought that the power changes in proportion to the square of the voltage. Therefore, it can be said that the conventional standby time display lacks reliability and is not very reliable.

Purpose The present invention has been made in view of the above points, and provides a standby system for a copying machine that can display a highly reliable standby time that approximates the actual standby time even if the input voltage to the heating means fluctuates. The purpose is to obtain a time display device.

Structure In order to achieve the above object, the present invention provides a fixing device that has a heating means and heats and fixes unfixed transfer paper, a temperature detection means that detects the temperature of this fixing device, and a temperature detection means that responds to the detection output of this temperature detection means. control means for controlling the heating state of the heating means; input fluctuation detection means for detecting fluctuations in the input voltage to the heating means; monitoring fluctuations at the input terminal obtained by the input fluctuation detection means and responding to the fluctuations; and a display means for displaying the obtained waiting time. shall be.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

First, the fixing device 1 used in the copying machine of this embodiment will be explained with reference to FIG. The fixing device 1 is of a heat fixing type and includes a pair of fixing rollers 2 and a pressure roller 3.

The fixing roller 2 has a heater 4 as a heating means in the center.
It has a core metal 2a around it, and the surface of the core metal 2a is a Teflon-treated roller surface 2b. On the other hand, the pressure roller 3 is formed by providing silicone rubber 3b around a core metal 3a.

In such a configuration, both days rotated in the direction of the arrow -
By inserting an unfixed transfer paper 6 having a toner image 5 between the rollers 2 and 3, this toner image 5 is fixed on the transfer paper 6 by being pressurized and heated.

In such a fixing device 1, a thermistor 7 is provided as a temperature detecting means that is in contact with the roller surface 2b on the fixing roller 2 side and constantly detects the temperature. Further, a temperature fuse 8 is provided in a space slightly away from the fixing roller 2. This temperature fuse 8 is for preventing an abnormal temperature rise of the fixing roller 2.

Next, the entire control power supply circuit of the fixing device 1, particularly the heater 4, etc., will be explained with reference to FIG. First, two circuit breakers 9 are provided to cut off overcurrent in a 200cm AC input line for power supply to the heater 4, and are connected to a noise filter 1o consisting of an L and C composite circuit. AC through this noise filter 10
The heater 4 is connected to the input line via electromagnetic relay contacts 11a and llb and an SSR (solid state relay) 12 that functions as a control means and switches the power to the heater 4. That is, the electromagnetic relay contacts 11a and 11b are used to control opening and closing of energization to the heater 4 by the electromagnetic relay 11.

In addition, the AC on the power supply side from the electromagnetic relay contacts 11a and llb
The power line drawn out from the input line is connected to the DC power supply unit 13 for generating DC voltage, but before that,
A circuit breaker 14 and a relay contact 15a are interposed. On the other hand, the electromagnetic relay 11 is powered by 24V that is stepped down from this power line through the secondary side of the transformer 16, and is closed by the relay contact 15b, the contact 17a of the door switch 17, and the temperature fuse 8. form a circuit. Here, small circuit breaker 14
is activated when the circuit consisting of the electromagnetic relay 15, the transformer 16, and the DC power supply section 13 is abnormal to ensure the safety of the circuit. That is, the large-capacity circuit breaker 9 will not operate and cannot be protected if there is some abnormality. Also, E
The electromagnetic relay 15 is energized by the XT and CNT signals, relay contacts 15a and 15b are closed, and the DC power supply section 13 is energized.If the door switch 17 is closed and the temperature fuse 8 is not blown, the electromagnetic relay 11 is also energized. It becomes energized and the relay contacts 11a and 11b are closed. This allows the heater 4 to be energized with AC power.

Here, the voltage being stepped down by the transformer 16 is that the 200V of the AC voltage is directly connected to the temperature fuse 8 and the door switch 1.
This is because it is dangerous to use it by routing it to a safety circuit such as No. 7. Further, the DC power supply unit 13 is supplied with AC power when the relay contact 15a is closed, and supplies DC voltage to each part of the machine, the control unit 18, the operation display unit 19, etc. Furthermore, this DC power supply section 13 also detects fluctuations in the AC input voltage and sends the resulting Vin to the control section 18. The door switch 17 is for interlocking and has two circuits, one circuit on the contact 17a side functions to operate the electromagnetic relay 11 that cuts off the electricity to the heater 4, and the other contact 17b functions as a control circuit. A door open signal is sent to the section 18, and is used for displaying the door open on the operation display section 19, etc. Further, a room temperature thermistor 20 is also connected to the control unit 18 . This room temperature thermistor 2
0 detects the room temperature or the temperature inside the machine.

Next, a more detailed configuration of the DC power supply section 13 is shown in FIG. First, AC via circuit breaker 14 etc.
After the input is rectified by the rectifier circuit 21, it is connected to each fuse 2.
It is supplied to the switching circuit 23 for 24■ and the switching circuit 24 for 5■ via 2a and 22b. These switching circuits 23 and 24 each convert the voltage to a low voltage through step-down transformers 25 and 26, and then output the voltage through rectified voltage detection circuits 27 and 28 that detect the rectified voltage again. That is, two DC voltages 24V and 5V are output, and the 24V output is supplied to 5SRI 2,
(2) is supplied to the control section 18 and the operation display section 19.

Furthermore, in this DC power supply unit 13, there is an A for the heater 4.
A switching power supply circuit 29 is added that monitors fluctuations in the C input voltage and serves as input fluctuation detection means. First, the primary side of the transformer 30 is connected to the AC input before the rectifier circuit 21 via a fuse 22c. A bridge-configured rectifier circuit 31 is provided on the secondary side of this transformer 30, and its full-wave rectified output is connected to a capacitor 32 and a resistor 3.
3 and smoothed by a smoothing circuit. This smoothed output is voltage-divided by a semi-fixed resistor 34 and a fixed resistor 35, and the input voltage Vin is monitored and outputted to the control section 18 from the midpoint of the connection.

Next, the configuration of the control section 18 will be explained with reference to FIG. First, a CPtJ 40 is provided that controls the entire system. A reset clock element 41 is connected to this CPU 40 and supplies a reset signal and a clock signal to the CPU 40. Here, the clock signal is a 5 MHz pulse-like signal for causing the CPU 40 to operate. The reset signal is sent to the CPU 40 when the power is turned on.
This is a signal for applying a reset for ms. Also,
Upper and lower RAMs 43 a and 43 b and upper and lower ROMs 44 a and 44 b are connected to the CPU 40 via upper and lower latch elements 42 a and 42 b.

Further, a ■/○ element 45 is connected to the CPU 40. Here, ROM44a and 44b have CPU40
A control program to be executed by the controller is written. As a result, the CPU 40 uses the ROM 44a.

The control program is read from 44b, and the control program is loaded from RAM43a, 4
Read and write the necessary information to 3b, ■/○ element 45
External control will be performed via the . That is, the CPU
40 as a main body, and RAM 43 and ROM 44 constitute calculation means. Here, latch elements 42a, 42b
are the ADO-AD7 and AD8 output from the CPU 40.
~ Since the address output and data output of AD15 are time-divided, the address output is latched by the address latch enable signal ALE and the RAM43a, 43'b, R
It is used to supply to OM44a, 44b, etc. A decoding element 46 is also connected to the CPU 40.

This decoding element 46 receives an output signal 5O from the CPU 40.
-32 and generates an ALE signal, RD (read) signal, WR (write) signal, INTA (indoor acknowledge) signal, etc.

Further, a timer element 47 is provided. This timer element 47 uses the 2.5 MHz PCLK signal supplied from the reset clock element 41 as a basic clock, and uses the C
Depending on the mode and data instructed by PU40, ○
The UTO outputs pulses with various frequency patterns.

48 is an interrupter element.

On the other hand, the I10 element 45 accesses input elements such as external sensors and keys, and output elements such as display LEDs and heaters. Here, it has three ports, A, B, and C, each having 8 bits, with the A and B ports serving as output ports, and the C port serving as an input port. Here,
The lower 4 bits PA○ to PA3 of the A port are connected to the A/D conversion element 49, and the other output ports PA4 to PA7 . P
BO-PB7 includes an external heater 4, a fixing drive motor, and a display LED on the operation unit (for example, for displaying standby time, which will be described later).
etc. are connected to. In addition, the C port has an operation display section 1.
The numeric keypad, temperature display key, etc. described later in 9 are connected, and the lowest 1 bit PCO is the D from the A/D conversion element 49.
It is configured to capture ATA signals.

Here, the A/D conversion element 49 is a thermistor 7.2.
Analog values obtained from 0, etc., and the aforementioned DC power supply section 1
The analog value of the input voltage Vin monitored by the switching power supply circuit 29 of No. 3 is converted into an 8-bit digital value, and is output to the CPI via the DATA output terminal and the I10 element 45.
This is to be transmitted to J40. Because of this behavior, CP
A/D conversion element 49 from U40 via ■/○ element 45
Four signals are output. First, the TE is always active (L level) when performing A/D conversion. Also, ADCLK receives DATA from this A/D conversion element 49.
This is a signal for outputting. At this time, since the A/D conversion element 49 used in this embodiment is based on MB4052 and has only one DATA terminal, data is output in serial. Therefore, every time a pulse signal is input to ADCLK, the data is output eight times starting from the most significant data. On the other hand, every time the CPU 40 issues an ADCLK pulse,
○Read the 0th bit of the C port of the element 45 and repeat this operation 8 times to obtain 8-bit data.

Since the A/D conversion element 49 has 1000 A/D conversion circuits, the remaining Co and C1 are signals for determining which circuit to select. In this embodiment, in order to perform A/D conversion on the two thermistors 7.2o and the input voltage Vin, the circuits are selectively switched using Co and C1.

Furthermore, a part of the operation display section 19 is shown in FIG.

The operation display section 19 is provided with keys such as a temperature display key 52 and a fixing temperature setting key 53 in addition to a numeric keypad 50 of ON9 and a clear key 51. The temperature display key 52 and the fixing temperature setting key S3 have self-illuminated lamps 52a and 5, respectively.
3a is provided.

Further, as displays, a fixing temperature display section 54, a room temperature display section 55, a fixing temperature setting value display section 56, and a standby time display section 57 as display means are provided.

As a result, this embodiment has a function of setting the fixing temperature, a function of displaying the fixing roller temperature and room temperature, and a function of displaying the waiting time until copying becomes possible. Each function will be explained.

■ Fixing temperature setting function After specifying this mode using the fixing temperature setting key 53,
By operating the numeric keypad 50 and clear key 51,
This is for inputting the set temperature.

However, in this embodiment, the fixing temperature setting range is 175 to 1
It is said to be 92℃. The input value is displayed on the fixing temperature setting value display section 56. Then, when the fixing temperature setting key 53 is pressed again, the input value at that time is fixed as the fixing temperature. At this time, the self-illuminating lamp 53a of the fixing temperature setting key 53 lights up, and inputs from the numeric keypad 5Q and clear key 51 are ignored. Further, when the fixing temperature setting key 53 is pressed, a non-setting mode is entered, the self-illuminated lamp 53a is turned off, and the setting temperature can be input again using the numeric keypad 50 or the clear key 51. FIG. 7 is a flowchart of open loop control showing such fixing temperature setting processing.

■ Fixing roller temperature and room temperature display function When the temperature display key 52 is pressed, the self-illuminating lamp 52a lights up, and the fixing temperature display section 54 and room temperature display section 55 display the temperature of the fixing roller 2 and room temperature detected by thermistors 7 and 20, respectively. is displayed. However, if the display mode is already displayed, by pressing the temperature display key 52, the non-display mode is entered, and the self-illuminated lamp 52a is turned off, and these temperature displays also disappear. The displayed temperature is 5
Updated every second. FIG. 8 shows a flowchart of open loop control for such temperature display.

■ Standby time display function This function can be used when turning on the power or during use.
How many minutes will it take for the warm-up to be completed when the fixing device 1 is waiting for warm-up until it reaches a temperature that can be used for copying, such as when reusing the machine after it has stopped and the temperature has changed to 1. The standby time display is automatically displayed when the power switch is turned on, and when the temperature of the fixing roller 2 reaches the fixing set temperature, the standby time display disappears.

Here, the standby time that should be displayed when the power is turned on, etc.
Basically, the CPU 40 calculates the difference between the fixing set temperature and the current temperature of the fixing roller 2 detected by the thermistor, and divides the difference by the temperature increase rate.

A major feature of this embodiment is that, when calculating such a standby time, the current input voltage to the heater 4 is monitored and a correction calculation is performed in accordance with the value of this input voltage. FIG. 1 is a flowchart showing closed loop control of such standby time display. First, when the power switch etc. is turned on, the input voltage Vi is generated by the switching power supply circuit 29 which transforms, rectifies, and smoothes the input voltage of the AC input.
n is connected to CP via A/D conversion element 49 and work/○ element 45.
It is taken into TJ40 and monitored. Here, several temperature increase rates are stored in advance in the ROM 44 etc. according to the value of the input voltage (experimental data etc. may be used), and one temperature increase rate corresponding to the current monitored input voltage is stored in advance. is selected. This selected temperature increase rate is used to calculate the waiting time.

The standby time calculated in this way is the standby time display section 5.
7 is displayed. After displaying, the waiting time is decremented by 1 every minute, and the display time decreases by one minute.

Then, there is a waiting time of one minute or less, and when the fixing set temperature is actually reached, the display disappears and the state becomes ready for copying. The standby time displayed in this manner has been corrected and calculated taking into account fluctuations in the input voltage to the heater 4, and is highly reliable with little deviation from the actual warm-up time.

Effects As described above, the present invention provides an input fluctuation detection means for detecting fluctuations in the input voltage to the heating means, monitors the fluctuations in the input voltage, uses a correction value according to the fluctuation, and uses a calculation means to detect the temperature detection means. The waiting time is calculated based on the detected temperature and displayed on the display means.
An appropriate standby time can be calculated according to the input voltage to the heating means at that time, and the standby time can be displayed with little deviation from the actual fixing warm-up time.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a flowchart showing standby time display processing, FIG. 2 is a side view of the fixing device, FIG. 3 is a block diagram of the entire control system for the fixing system, and FIG. 4 5 is a block diagram of the control section, FIG. 6 is a plan view of the operation display section, FIG. 7 is a flowchart showing the fixing temperature setting process, and FIG. 8 is the temperature display process. It is a flowchart. 1 fixing device, 4 heating means, 7 temperature detection means, 12
Control means, 29 Human power fluctuation detection means, 4o Calculation means, 57-Display means, %Z] 6F Jl 17 Start again? N N Osetsuou--middle? , N N 1. ,,-1-?

Claims (1)

[Claims] A fixing device that has a heating device and heats and fixes unfixed transfer paper, a temperature detection device that detects the temperature of the fixing device, and a control device that controls the heating state of the heating device in accordance with the detection output of the temperature detection device. and an input fluctuation detection means for detecting fluctuations in the input voltage to the heating means, and a temperature detected by the temperature detection means by monitoring the fluctuations in the input voltage obtained by the input fluctuation detection means and using a correction value according to the fluctuations. 1. A standby time display device for a copying machine, comprising: a calculation means for calculating a standby time until the fixing device reaches a usable temperature based on the above, and a display means for displaying the obtained standby time.