JPH05323710A - Image forming device - Google Patents

Abstract

PURPOSE:To control a fixing member corresponding to the frequency of use so that it reaches an arbitrary power save temperature which is lower than the fixing temperature, and to set in such a manner that the timing at which the fixing member is controlled so as to reach the power save temperature can vary with the frequency of use. CONSTITUTION:A CPU 21 controls a heater 11c in a power save period so that it reaches the power save temperature, alternatively, it makes a timer 21a measure the elapse of time after the completion of the previous image formation and, when the elapse of time coincides with the delay time, controls the heater 11c so that it reaches the power save temperature. A user can input the power save period, power save temperature and delay time by the use of a touch panel 30.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for forming an image by an electrophotographic process, and more particularly, an image forming method capable of reducing energy consumption during non-image forming by controlling the temperature of a fixing member such as a fixing roller. Regarding the device.

[0002]

2. Description of the Related Art Generally, in an image forming apparatus using an electrophotographic method, it takes a certain period of time from when the main power source is turned on to when an image can be formed. This is because it takes a certain period of time to bring the fixing roller incorporated in the image forming apparatus to a high fixing temperature by the heater. Therefore, even when the image formation is not performed, the main power supply is always turned on so that the image forming apparatus is ready for the image formation. However, when the image forming apparatus is set in an image formable state, electric power is consumed by the heater, which causes a problem that running cost increases.

Japanese Laid-Open Patent Publication No. 60-73559 has a time setting switch, a preheating operation start switch, a preheating operation end switch, and the like. The pre-heating operation is controlled so that the preheating device is controlled to a high temperature at the end of the preheating operation, the fixing device is heated to a high temperature, and the toner image transferred to the printing paper can be fixed at any time during the printing operation. It is shown.

[0004]

However, in the electrophotographic machine having the above structure, the preheater can control only two temperatures. One control temperature is the set temperature during the preheating operation, and the other control temperature is the set temperature during the printing operation.
Therefore, when the set temperature during the preheating operation is increased, the waiting time for the user before printing can be reduced, but the power consumption increases, and when the set temperature during the preheating operation is reduced, the power consumption increases. However, the waiting time until printing becomes possible increases.

Generally, the use frequency of an electrophotographic machine such as a copying machine greatly varies depending on the time of day, for example, the frequency of use decreases outside the working hours, and the frequency of use is extremely low during the night hours. .. Since it is not necessary to print the electrophotographic machine in a short time during such a low frequency of use, an electrophotographic machine capable of further reducing power consumption according to the frequency of use is required.

In order to solve the above problems, the object of the present invention is to control the fixing member to an arbitrary power save temperature lower than the fixing temperature in accordance with the frequency of use, or to adjust the power saving temperature of the fixing member in accordance with the frequency of use. An object of the present invention is to provide an image forming apparatus capable of variably setting the control timing.

[0007]

In order to solve the above problems, the present invention provides an image forming apparatus having a fixing member which is heated to a high fixing temperature by a heater to apply heat to a toner image. A temperature detecting means for detecting a temperature, a time measuring means for measuring the present time, a power save time zone which is an arbitrary time zone and a power which is an arbitrary temperature lower than the fixing temperature corresponding to the power save time zone. When the setting means capable of setting the save temperature and the time measured by the time measuring means are within the power save time zone, the fixing member refers to the temperature detection signal of the temperature detecting means at the time of non-image formation to cause the fixing member to have the power. And a control means for controlling the amount of heat generated by the heater so as to attain the save temperature.

Further, in an image forming apparatus provided with a fixing member that is heated to a high fixing temperature by a heater and heat is applied to a toner image, a clocking means for clocking the present time and a power save time which is an arbitrary time zone. And a setting means capable of setting a drive stop command for the heater in correspondence with the belt and the power save time zone, and driving the heater during non-image formation when the time measured by the time measuring means is within the power save time zone. And a control means for stopping.

Further, in an image forming apparatus provided with a fixing member which is heated to a high fixing temperature by a heater and applies heat to a toner image, temperature detecting means for detecting the temperature of the fixing member and current time and time length. A clocking means for clocking, a power save time zone which is an arbitrary time zone and an input means capable of setting a delay time which is an arbitrary time length corresponding to this power save time zone, and the clocking time of said clocking means is When the time is within the power save time zone, the time measuring means measures the elapsed time from the completion of the previous image formation, and when the elapsed time matches the delay time, the temperature detection signal of the temperature detecting means is referred to. And a control means for controlling the heat generation amount of the heater so that the fixing member has a power save temperature lower than a preset fixing temperature from the fixing temperature. Characterized by comprising.

Further, the setting means is provided with an input section for inputting data from outside the apparatus.
Further, the setting means is provided with a non-volatile memory for storing the setting data when the main power is cut off, or a memory to which power for storing the setting data is supplied by a backup power supply when the main power is cut off. ..

[0011]

According to the above means, by setting the power save time zone and the power save temperature by the setting means, the fixing member can be set to a power save temperature lower than the fixing temperature during non-image formation in the power save time zone. it can.

By setting the power save time zone and the drive stop command by the setting means, it is possible to stop the heat generation of the heater during non-image formation in the power save time zone.

By setting the power save time zone and the delay time by the setting means, the fixing member can be brought to the power save temperature when the image formation is not performed for the delay time in the power save time zone.

Further, since the setting means is provided with an input section for inputting data from the outside of the mounting, arbitrary data can be set from the outside. Furthermore, the setting means,
The non-volatile memory that saves the setting data when the main power is turned off, or the memory that is supplied with the power to save the setting data by the backup power supply when the main power is turned off Can be saved.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a cross-sectional view of an image forming apparatus according to an embodiment of the present invention, in which 1 is an image forming apparatus main body including an upper case 1a and a lower case 1b, and 2 is an upper case 1a with respect to a lower case 1b. A shaft 5 for rotatably supporting the photosensitive member 5 is a belt-shaped photosensitive member installed substantially in the center of the image forming apparatus main body 1. Around the photosensitive member 5, known charging means 6, developing means 7, transfer The electrophotographic forming process means other than the optical writing means, which will be described later, of the means 8 and the cleaning means 9 is arranged.

Further, 3 is a sheet feeding cassette, 12 is a sheet feeding roller, 13 is a pair of registration rollers, 11 is a fixing roller 11a, a pressure roller 11b, a heater 11c, and a thermistor 11d for detecting the temperature of the fixing roller 11a. The fixing means, 15 is a paper discharge roller, 14 is a paper discharge tray, and 17 is an optical writing means installed below the photoconductor 5.

In the above laser printer, the paper (not shown) fed from the paper feed cassette 3 by the paper feed roller 12 is conveyed to the upper side of the photoconductor 5 at a timing by the registration roller pair 13. .. The photoconductor 5 is driven and guided by the roller 4 in the counterclockwise direction indicated by the arrow.
The charging means 6 uniformly charges the surface, and the laser light L from the optical writing means 17 is irradiated through the cylinder lens 18 to form an electrostatic latent image. This electrostatic latent image is made into a toner image by toner (not shown) when passing through the developing means 7. Then, this toner image is transferred by the transfer means 8 onto the lower surface of the sheet conveyed above the photoconductor 5.

The sheet transferred as described above is conveyed between the fixing roller 11a and the pressure roller 11b of the fixing means 11 and the toner image is fixed. Then, the sheet exits the fixing unit 11 and is discharged to the discharge tray 14 by the discharge roller 15.

Although not shown in FIG. 2, a control board for performing sequence control such as temperature control of the fixing roller based on the above operation and temperature information from the thermistor is provided in the main body of the image forming apparatus. Has been.

FIG. 1 is a block diagram showing the control board of this embodiment.

Reference numeral 21 is a CPU (central processing unit), 22 is a ROM (read only memory) storing control programs and basic software, 23 is a RAM (random access memory) for temporarily storing input data, and 24 is an input. EEPROM for data storage (read only memory that can be read by electric erasing), 25 is RTC (real time clock) which is a time measuring means for measuring the current time, 26 is an A / D (analog / digital) converter, 27 is An I / F (interface) 28, which is an input / output port for the control board, is a data bus between the members. The CPU 21 is connected with a timer 21a which is a time measuring means for measuring the time length,
A backup power supply 24a that supplies power for saving data when the main power supply is cut off is connected to M24.
The thermistor 11d, which is the temperature detecting means for the fixing roller 11a, is connected to the / D converter 26.

Further, the I / F 27 has a heater control circuit for a heater 11c for heating a touch panel 30 which is a user's input section to the EEPROM 24, an LCD (liquid crystal display) 40 which is a display section for various data for the user, and a fixing roller 11a. Fifty
Etc. are connected. The setting means for the user to set various data on the control board is composed of the EEPROM 24, the data bus 28, the I / F 27, the touch panel 30, and the like.

FIG. 3 is a circuit diagram of the heater control circuit of this embodiment.

Reference numeral 51 is an AC power source supplied through a noise filter (not shown), 52 is a current fuse for limiting overcurrent, 53 is a temperature fuse for limiting overheating of the heater 11c, 54
Is a triac, 55 is a photocoupler, 56 is an AC current zero cross detector, and 57 is a driver for outputting a signal corresponding to a control signal output from the CPU 21 via the I / F 27.

In the heater control circuit 50, the control board outputs a drive signal to the driver 57 so that a gate current flows from the photocoupler 55 to the triac 54 and a drive stop signal is output to the driver 57. The gate current of 55 turns off. As a result, when the control board outputs the drive signal, the AC power supply 51 applies the drive current to heat the heater 11c, and when the control board outputs the drive stop signal, the drive current is cut off and the heater 11c is turned off. To do.

The thermistor 11d detects the temperature of the roller surface of the fixing roller 11a which is internally heated by the heater 11c and outputs an analog signal corresponding to this temperature to the A / D converter 26 for A / D conversion. The device 26 converts the analog signal of the thermistor 11d into a digital signal and outputs the digital signal corresponding to the temperature of the fixing roller 11a to the CPU 21 via the data bus 28.

The image forming apparatus of the present embodiment is constructed so that the user can select the operation mode, and the operation mode includes the normal mode N and the power save modes P1 and P2.

In the power save mode P1, the user uses the touch panel 30 to set the power save time zone and the power save temperature or the heater corresponding to the power save time zone.
This is an operation mode set by inputting a drive stop command for 11c to the device.

FIG. 4 is an explanatory diagram showing an input example of the power save time zone and the power save temperature.

Here, the user sets the power save mode P1 in the time zone except the time from 9:00 to 17:00 when the frequency of use of the apparatus is very high. In the power save time zone, t1 is input as the power save temperature t in correspondence with the time zone from 17:00 to 18:00, which is relatively frequently used.
The t2 is input in correspondence with 0 o'clock, and the drive stop command is input in correspondence with 0 o'clock to 9 o'clock and 20 o'clock to 24 o'clock, which are rarely used. The input power save temperature t has a relationship of t2 <t1 <(fixing temperature). By setting the power save mode P1 in this manner, the image forming apparatus can be configured to fix the fixing roller during the power save time.
11a is set to a power save temperature t1 or t2 lower than the fixing temperature, or heating of the fixing roller 11a by the heater 11c is stopped, and the fixing roller 11a is heated to the fixing temperature only when an image forming command is input from the outside. After the image formation is completed, the fixing roller 11a is again set to the power save temperature t
Set to 1, t2, or stop heating to the fixing roller 11a. The power save temperature t is set to t1 in correspondence with the power save time zone that is frequently used, and is t2 which is lower than t1 in correspondence to the power save time zone in which the use frequency is relatively low.
As a result, the waiting time of the user until the fixing roller 11a is heated to the fixing temperature in the frequently used time zone can be reduced, and the heater 11 can be used in the less frequently used time zone.
The power consumption of c can be reduced. Furthermore, by turning off the heater 11c in a time period when it is rarely used, the power consumption of the device can be brought close to zero.

FIG. 5 is an explanatory view showing an input example of the power save time zone and the delay time.

Here, the user sets the above-mentioned power save mode P1 for the time zones from 0 o'clock to 9 o'clock and from 20 o'clock to 24 o'clock when the frequency of use of the device is small, and from 9 o'clock to 20 o'clock. The power save mode P2 is set for the time zones up to. The power save mode P2 is set by inputting a power save time zone and a delay time d corresponding to the power save time zone and having a desired time length.

Here, the user inputs d1 as the delay time d corresponding to the power saving time zone from 9:00 to 17:00 when the frequency of use of the device is high, and the frequency of use is relatively low.
Corresponding to the power save time zone from 7:00 to 20:00 d2
You are typing. The input delay time d is d1> d2
Have a relationship. By setting the power save mode P2 in this way, in the power save time zone, the image forming apparatus sets the fixing roller 11a when the elapsed time from the completion of the previous image formation becomes the delay times d1 and d2. The power saving temperature t0 lower than the fixing temperature is set from the fixing temperature. Here, the power save temperature t0 is a temperature preset in the ROM 22 as a constant.

Further, the image forming apparatus forms the image by raising the fixing roller 11a to the fixing temperature when an image forming command is input from the outside, and the elapsed time from the completion of the image forming is the delay times d1 and d2. Until then, the fixing roller 11a is maintained at the fixing temperature.

The delay time d is set to d1 in correspondence with the power saving time zone of high usage frequency, and is set to d2 shorter than d1 in correspondence with the power saving time zone of relatively low usage frequency. It is possible to prevent the work efficiency from decreasing due to the increase in the waiting time in the time zone, and it is possible to make the power consumption of the heater 11c extremely small in the time zone in which the frequency of use is low.

By controlling the temperature of the fixing roller 11a as described above, it is possible to prevent the user from waiting when the apparatus is intensively used in a short time, for example, in a time zone of low usage frequency. The power consumption of the heater 11c can be reduced corresponding to the decrease in the frequency of use.

FIG. 6 is a flowchart showing a data input method for setting the power save mode.

In order to set the power save modes P1 and P2, the user inputs the start time using the ten keys on the touch panel 30 (S1) and then the end time (S).
2). As a result, the power saving time zone is RAM23.
Entered in. In S3, the user selects the operation mode corresponding to the input time zone, and the power save mode P
When 1 is selected, power save temperature t or heater 11
One of the drive stop commands for c is input using the numeric keypad or function key of the touch panel 30 (S4), and when the power save mode P2 is selected, the delay time d is input using the numeric keypad or the like. By repeating the above operation, it is possible to input different power save temperatures t, delay times d, etc. corresponding to a plurality of different time zones, and if all the data input is completed (S
6) The internal processing of the input data is executed on the control board by the function keys of the touch panel 30.

By executing the internal processing, the above data is stored in the plurality of data tables of the EEPROM 24 from the RAM 23. As mentioned above, the EEPROM 24
Since it is equipped with the backup power supply 24a, the stored data can be saved even when the main power supply of the device is turned off. Further, by using a non-volatile memory such as a magnetic memory instead of the EEPROM 24, it becomes possible to save data when the main power supply is cut off without connecting a backup power supply.

Table 1 is a data table for setting the power save mode. When the power save mode P1 is set, the start time, the end time and the power save temperature or code are stored in a predetermined storage area. ..
Here, the code is stored by pressing the function key of the touch panel 30 corresponding to the drive stop command for the heater 11c. Further, when the power save mode P2 is set, the start time, the end time and the delay time are stored in a predetermined storage area.

[0042]

[Table 1]

FIG. 7 is a flow chart showing the control operation when starting the power save mode.

The CPU 21 of the control board controls the RT at regular intervals.
Read the current time measured by C25 (S1
1) Compare the current time with the start time of the data table of the EEPROM 24 (S12), and if the current time and the start time match, read the data from the corresponding data table.
(S13), the read data is stored in the register of the CPU 21, and the kind of the power save modes P1 and P2 is judged according to the data contents (S14), and the control of the power save modes P1 and P2 is started based on the data contents. (S1
5, S16).

FIG. 8 is a flow chart showing the control operation when ending the power save mode.

The CPU 21 of the control board controls the RT at regular intervals.
Read the current time measured by C25 (S2
1) Compare the current time with the end time stored in the register of the CPU 21 (S22), and if the current time and the end time match, clear the register data and set the power save modes P1 and P2. Forcibly terminate control
(S23), the fixing roller 11a is controlled to the fixing temperature.

FIG. 9 shows C in the power save mode P1.
It is a flow chart which shows control operation of PU.

When executing the power save mode P1,
The CPU 21 determines the state of the apparatus (S31), monitors the end of image formation at a constant cycle during image formation, and when the image formation is not executed, the power save temperature as the target roller temperature of the fixing roller 11a. t is set (S32), and the heat generation amount of the heater 11c is controlled so that the fixing roller 11a reaches the power save temperature t (S33).

In the power save mode P1, when the image forming command is input, the fixing temperature is set as the target roller temperature at the input and the process returns to S31.

FIG. 10 shows C in the power save mode P2.
It is a flow chart which shows control operation of PU.

When executing the power save mode P2,
The CPU 21 determines the state of the apparatus (S41), resets the elapsed time of the timer 21a, which is a time length measuring means, to 0 during image formation (S42), and when the image formation is not executed, the timer The delay time d is set in 21a and the counting of the elapsed time is started (S43). The timer 21a outputs a count-up signal to the CPU 21 at the timing when the elapsed time matches the delay time d. The CPU 21 determines from the count-up signal that the elapsed time matches the delay time d (S44), sets the power save temperature t0 as the target roller temperature of the fixing roller 11a (S45), and the fixing roller 11a receives the power save temperature. The heat generation amount of the heater 11c is controlled so as to become t0 (S46).

In the power save mode P2, when the image forming command is input, the fixing temperature is set as the target roller temperature at the input and the process returns to S41.

FIG. 11 is a flowchart showing the temperature control operation for the fixing roller.

The CPU 21 reads the target roller temperature
(S51), the fixing roller 1 detected by the thermistor 11d
The actual roller temperature of 1a is read (S52), the target roller temperature and the actual roller temperature are compared (S53), and when the roller temperature ≧ the target roller temperature, the heater 11c is turned on to generate heat (S53).
54), when the roller temperature ≦ the target roller temperature, the heater 11c is turned off to stop the heat generation (S55). By performing this control operation in a constant cycle, the fixing roller 11a is controlled to a substantially target roller temperature.

In the image forming apparatus of this embodiment, the user sets the power save temperature t close to the fixing temperature in the power save time zone which is frequently used, so that the fixing roller
Since the waiting time until 11a reaches the fixing temperature can be shortened, the power consumption can be reduced and the image forming work can be efficiently executed, and the low power save temperature or the drive stop command can be set in the relatively infrequently used time zone. By setting, the power consumption of the device can be significantly reduced. Alternatively, the user sets a long delay time d in a power save time zone that is frequently used, so that the fixing roller 11a is maintained at the fixing temperature according to the frequency of use, so that a waiting time occurs for the user. The number of opportunities is reduced, the image forming work can be efficiently performed, and the fixing roller 11a is maintained at the power save temperature t by setting the short delay time d in the relatively infrequently used time zone. Since it becomes longer, the power consumption of the device can be significantly reduced.

[0056]

As described above, according to the present invention, by setting the power save time zone and the power save temperature by the setting means, the fixing member is brought to the power save temperature during non-image formation in the power save time zone. Therefore, the energy consumption of the apparatus can be reduced, and the waiting time until the user can form an image can be shortened by setting a higher power save temperature corresponding to a time zone in which the apparatus is frequently used. Therefore, efficient work can be performed, and energy consumption of the device can be further reduced by setting a low power save temperature in correspondence with a time zone of low use frequency.

Further, by setting the power save time zone and the drive stop command by the setting means, it is possible to stop the heat generation of the heater during non-image formation in the power save time zone, so that the energy consumption of the apparatus is greatly reduced. it can.

By setting the power save time zone and the delay time by the setting means, the fixing member can be brought to the power save temperature when the image formation is not performed for the delay time in the power save time zone. The energy consumption of the device can be reduced according to the frequency of use of the device, and the chance of waiting for the user can be reduced by setting a long waiting time corresponding to the time of frequent use. By setting a short waiting time corresponding to a low frequency time zone, it is possible to increase the time ratio in which the fixing member is maintained at the power save temperature.

Further, since the setting means is provided with the input section for inputting data from the outside of the apparatus, arbitrary data can be set from the outside, so that the data setting work can be efficiently performed. Further, since the setting means has a non-volatile memory for storing the setting data when the main power is cut off, or a memory to which power for saving the setting data is supplied by the backup power supply when the main power is cut off, Also, since the setting data can be saved, it is not necessary to reset the data after the main power is turned on if the data is the same.

[Brief description of drawings]

FIG. 1 is a configuration diagram illustrating a control board of an image forming apparatus that is an embodiment of the present invention.

FIG. 2 is a sectional view of the present embodiment.

FIG. 3 is a circuit diagram of a heater control circuit of this embodiment.

FIG. 4 is an explanatory diagram showing an input example of a power save time zone and a power save temperature.

FIG. 5 is an explanatory diagram showing an input example of a power save time zone and a delay time.

FIG. 6 is a flowchart showing a data input method for setting a power save mode.

FIG. 7 is a flowchart showing a control operation when starting a power save mode.

FIG. 8 is a flowchart showing a control operation when ending the power save mode.

FIG. 9 is a flowchart showing the control operation of the CPU in the power save mode P1.

FIG. 10 is a flowchart showing the control operation of the CPU in the power save mode P2.

FIG. 11 is a flowchart showing a temperature control operation for the fixing roller.

[Explanation of symbols]

11 ... Fixing means, 11a ... Fixing roller, 11c ... Heater,
11d ... Thermistor, 21 ... CPU, 21a ... Timer, 24
… EEPROM, 24a… Backup power supply, 25… RT
C, 30 ... Touch panel, 50 ... Heater control circuit.

Claims (5)

[Claims] 1. An image forming apparatus having a fixing member which is heated to a high fixing temperature by a heater and applies heat to a toner image, and a temperature detecting unit for detecting the temperature of the fixing member and a current time. A timer means, a power save time zone which is an arbitrary time zone, and a setting means which can set a power save temperature which is an arbitrary temperature lower than the fixing temperature in correspondence with this power save time zone, and a clock time of the timer means. Is within the power save time zone, control for controlling the heat generation amount of the heater by referring to the temperature detection signal of the temperature detection means during non-image formation so that the fixing member reaches the power save temperature. An image forming apparatus comprising: 2. An image forming apparatus having a fixing member which is heated to a high fixing temperature by a heater to apply heat to a toner image, and a time keeping means for measuring the present time and a power save time which is an arbitrary time zone. And a setting means capable of setting a drive stop command for the heater in correspondence with the belt and the power save time zone, and driving the heater during non-image formation when the time measured by the time measuring means is within the power save time zone. An image forming apparatus, comprising: a control unit for stopping the operation. 3. An image forming apparatus having a fixing member which is heated to a high fixing temperature by a heater and applies heat to a toner image, the temperature detecting unit detecting a temperature of the fixing member, and a current time and time length. A clocking means for clocking, a power save time zone which is an arbitrary time zone and an input means capable of setting a delay time which is an arbitrary time length corresponding to this power save time zone, and the clocking time of said clocking means is If the time is within the power save time zone, the time counting means measures the elapsed time from the completion of the previous image formation,
When the elapsed time matches the delay time, the heater is set so that the fixing member has a power save temperature lower than the preset fixing temperature from the fixing temperature by referring to the temperature detection signal of the temperature detecting means. An image forming apparatus, comprising: a control unit that controls the heat generation amount of the image forming apparatus. 4. The image forming apparatus according to claim 1, wherein the setting unit includes an input unit for inputting data from outside the apparatus. 5. The setting means comprises a non-volatile memory for storing the setting data when the main power is cut off, or a memory to which power for storing the setting data is supplied by a backup power supply when the main power is cut off. The image forming apparatus according to any one of claims 1 to 4, which is characterized in that.