JP2012141547A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus which solves such problems that a temperature within the apparatus is not decreased to equal to or lower than a predetermined value if the output of a cooling fan in a stand-by state is a fixed value and adversely that the temperature within the apparatus is decreased more than necessary, when the apparatus moves to an energy saving mode.SOLUTION: An image forming apparatus performs a control for adjusting an output of a cooling fan in a stand-by state corresponding to "time set by a user from the completion of an image formation till the moving to the energy saving mode" and "a temperature within the image forming apparatus when printing has been completed", thereby making it possible to certainly stop the cooling fan when moving to the energy saving mode to realize the reduction of power consumption. At the same time, the optimal output of the cooling fan in the stand-by state realizes the reduction of noise.

Description

  The present invention relates to a method for controlling a cooling fan of an image forming apparatus having an energy saving mode.

  2. Description of the Related Art Recent image forming apparatuses have a function of reducing power consumption in a state called an energy saving state or an energy saving mode as a countermeasure for environmental problems and energy problems. In this specification, the standby state is a standby normal state in which an operation can be performed immediately upon receiving an operation instruction, and the energy saving mode has lower power consumption than the standby state. Transition to the energy saving mode is made when the standby state continues for a predetermined time, and the transition time from the end of printing to the energy saving mode can be set by the user.

  In order to reduce power consumption in the energy saving mode, it has a drive power supply that supplies power to peripheral devices and motor control units, and a control power supply that supplies power to the control units. There is a technique to stop.

  The image forming apparatus is equipped with a cooling fan in order to cool the inside of the apparatus during the image forming operation. In the standby state or the energy saving mode, the amount of heat generated is smaller than in the image forming operation, and the cooling fan may not be driven. Even in such a case, when the drive of the fan is stopped immediately when shifting from the image forming operation to the standby state, the in-machine temperature of the image forming apparatus is temporarily increased or the temperature is decreased. It may take time and cause damage to the image forming apparatus.

  For this reason, a temperature sensor or the like is provided in the image forming apparatus, the temperature is monitored, and the cooling fan is driven until the inside of the apparatus becomes a specified temperature or less, or the operation amount of the image forming operation as described in Patent Document 1 is measured. However, there is a method of driving the cooling fan for a time corresponding to the measured operation amount.

JP 2004-163628 A

  However, in the above-described conventional method, no reference is made to a method for controlling the output of the cooling fan in the standby state. Therefore, the following concerns are raised when shifting from the standby state to the energy saving mode.

  If the time setting from the end of printing to the transition to the energy saving mode is short and the output of the cooling fan in the standby state is small, the in-machine temperature may not fall below the specified value even when attempting to shift to the energy saving mode. In such a case, the cooling fan cannot be stopped despite the elapse of time for shifting to the energy saving mode. As a result, for example, the drive power supply that supplies power to the cooling fan cannot be stopped, and the expected energy saving effect cannot be obtained.

  If the time setting from the end of printing to the transition to the energy saving mode is long and the output of the cooling fan in the standby state is large, the inside of the apparatus can be sufficiently cooled before shifting to the energy saving mode. However, if the output of the cooling fan is large, the noise level in the standby state increases, which causes usability deterioration.

The present invention has been made in view of the above problems, and adjusts the output of the cooling fan during standby to control the in-machine temperature to reach a predetermined value in accordance with the timing of shifting to the energy saving mode. Specifically, the output of the cooling fan in the standby state is adjusted according to the “time from the end of image formation set by the user to the transition to the energy saving mode” and the “in-machine temperature of the image forming apparatus at the end of printing”. Take control.
By performing this control, the cooling fan can be surely stopped at the timing of shifting to the energy saving mode, and the power consumption can be reduced. In addition, the noise level can be reduced by optimizing the output of the cooling fan in the standby state.

In order to achieve the above object, the present invention has the following means.
(1) The output of the cooling unit in the standby state is controlled according to the time from the end of image formation to the transition to the energy saving state. Specifically, when the time stored in the time recording unit is shorter than a predetermined value, the output of the cooling device in the standby state is set to a high output, and the time stored in the time recording unit is a predetermined value If longer, control is performed to reduce the output of the cooling device in the standby state.
(2) The output of the cooling device in the standby state is determined according to the in-machine temperature at the end of image formation predicted by the control unit that controls the image forming apparatus and the time from the end of image formation to the transition to the energy saving state. Control to change.
(3) The output of the cooling device in the standby state according to the in-machine temperature at the end of image formation measured by the temperature detection element arranged in the image forming apparatus and the time from the end of image formation to the transition to the energy saving state Control to change.
(4) The output of the cooling device in the standby state can be selected by the user, and the output of the cooling device in the standby state is set to a high output is “energy saving priority mode”, and the output of the cooling device in the standby state Control that sets the low output to “low noise priority mode” is performed.

  According to the image forming apparatus described in (1), control is performed to adjust the output of the cooling fan in the standby state according to the time from the end of printing set by the user to the transition to the energy saving mode. By performing this control, when the energy saving mode transition time is short, the internal temperature can be reliably lowered to a specified value or less when the energy saving mode is shifted by increasing the number of rotations of the cooling fan. As a result, it becomes possible to quickly shift to the energy saving mode, and the power consumption can be reduced. Further, when the energy saving mode transition time is long, the noise in the standby state can be reduced by lowering the number of rotations of the cooling fan.

  According to the image forming apparatus described in the above (2), the control for adjusting the output of the cooling fan in the standby state according to the internal temperature at the end of printing set by the user and the time from the end of printing to the transition to the energy saving mode. Do. Further, the temperature inside the apparatus at the end of printing is estimated by the printer control CPU. As a result, the output of the cooling fan in the standby state can be more optimally controlled, and further reduction in power consumption and noise can be realized.

  According to the image forming apparatus described in the above (3), the control for adjusting the output of the cooling fan in the standby state according to the internal temperature set at the end of printing set by the user and the time from the end of printing to the transition to the energy saving mode. Do. The internal temperature at the end of printing is performed by monitoring a temperature detection element arranged in the printer. As a result, the output of the cooling fan in the standby state can be more optimally controlled, and further reduction in power consumption and noise can be realized.

  According to the image forming apparatus described in (4), the user can select either “energy saving priority mode” or “low noise priority mode”, and output of the cooling fan in a standby state according to the selected result. Control to adjust. By this control, the state of the image forming apparatus during standby can be selected according to the user's preference, and usability can be improved.

1 is a block diagram of an image forming apparatus according to a first embodiment. Flowchart diagram of image formation control in Embodiment 1. The figure which shows the relationship between the internal temperature in Example 2, and the number of printed sheets The figure which shows the relationship between the in-machine temperature in Example 2, and the elapsed time from the end of printing. The figure explaining the method of calculating the in-machine temperature in Example 2 Flowchart diagram of image formation control in Embodiment 2. FIG. 6 is a block diagram illustrating a control unit of an image forming apparatus according to a third embodiment. The figure which shows the relationship between thermistor resistance value and temperature in Example 3. The figure which shows the voltage value of P4 in Example 3, and the relationship of temperature. Flowchart of image formation control in Embodiment 3. Flowchart diagram of image formation control in embodiment 4. Configuration diagram of image forming apparatus

[Example 1]
FIG. 12 is a configuration diagram of a color laser printer with an optional device which is the image forming apparatus of the present embodiment.

  401 is a color laser printer, 402 is a paper feed cassette for storing the recording paper 32, 404 is a pickup roller for feeding the recording paper 32 from the paper feed cassette 402, and 405 is a paper feed for feeding the recording paper 32 fed by the pickup roller 404. A paper roller 406 is paired with the paper feed roller 405, a retard roller for preventing double feeding of the recording paper 32, and 407 is a registration roller pair.

  Reference numeral 409 denotes an electrostatic adsorption conveyance transfer belt (hereinafter referred to as ETB) which conveys the recording paper 32 by electrostatic adsorption. A process cartridge 410 includes a photosensitive drum 305, a cleaning unit 306 that removes toner on the photosensitive drum 305, a charging roller 303, a developing roller 302, and a toner storage container 411, and is attachable to and detachable from the color laser printer 401. It has become.

  A scanner unit 420 emits a laser beam modulated based on each image signal sent from the printer control CPU 207, and scans each photosensitive drum 305 with the laser beam from each laser unit 421. Polygon mirror 422, scanner motor 423, and imaging lens group 424. The process cartridge 410 and the scanner unit 420 exist for four colors (yellow Y, magenta M, cyan C, and black B).

  A fixing device 431 includes a fixing roller 433 including a heater 432 for heating, a pressure roller 434, and a fixing discharge roller pair 435 for conveying the recording paper 32 from the fixing roller.

  Reference numerals 451, 452, and 453 denote DC brushless motors, 451 denotes a main motor that drives the process cartridge 410, 452 denotes an ETB motor that drives the ETB, and 453 denotes a fixing motor that drives the fixing device.

  An engine controller 201 is a control unit of the laser printer 401, and includes a printer control CPU 207, various input / output control circuits (not shown), and the like.

  A power circuit 202 steps down the primary AC current after smoothing, and supplies power to the DC brushless motors 451, 452, 453, the engine controller 201, and the like.

  A cooling fan 208 cools the cartridge 410. The cooling fan 208 is controlled by the engine controller 401.

  A reception control IC 440 receives image data sent from a host computer 441 such as a personal computer.

  Reference numeral 651 denotes an optional paper feeding unit for accommodating different recording papers, and includes a paper feeding cassette 652 that stores the recording paper 32 and a pickup roller 654 that feeds the recording paper 32 from the paper feeding cassette 652.

  Reference numeral 801 denotes an optional paper discharge unit that sorts the recording paper discharged from the color laser printer 401 into a paper discharge tray every predetermined number. The motor 802 that drives the pair of conveyance rollers 804 and 805 and the paper discharge tray 806 are moved up and down. A motor 803 to be operated.

  Reference numeral 701 denotes an optional transport unit that transports recording paper discharged from the color laser printer 401 to an optional paper discharge unit 801, and includes a motor 702 that drives a pair of transport rollers 703 and 704.

  Reference numeral 901 denotes an optional image scanner including a document conveying unit 930 and a document reading unit 931. Reference numeral 902 denotes a document transport motor for transporting the document 932, 904 an exposure unit, 905 an exposure means, 906 a mirror, 903 a scanner drive motor that horizontally moves the exposure unit 904, 907 a reflection device, 908 and 909 a mirror, 910 Is a light receiving device, and 940 is an image scanner controller unit that controls the operation of the optional image scanner 901 and converts a signal received by the light receiving device 910 into image data.

  Next, an image forming operation will be described.

  First, image data is transmitted from the host computer 441 to the reception control IC 440. The engine controller 201 that has received the image starts driving the scanner motor 423, the main motor 451, the ETB motor 452, and the fixing motor 453 at a predetermined timing, and drives the pickup roller 404, the paper feed roller 405, and the retard roller 406. Then, the recording paper 32 is fed out from the paper feed cassette 402. Thereafter, the basis weight discrimination means 323 discriminates the thickness of the recording paper, selects the image forming speed and image forming conditions according to the recording paper, and if the image forming speed needs to be changed according to the discrimination result of the recording paper, the main motor 451, the ETB motor 452, and the rotation speed of the fixing motor 453 are changed. In addition, the temperature detection sensor 324 detects the ambient temperature of the image forming apparatus 401 and corrects the image forming conditions selected according to the detection result. The recording paper is conveyed to the registration roller pair 407 and temporarily stops.

  Next, on / off control of the laser unit 421 is performed according to an image signal depending on the bitmap data, and the photosensitive drum 305 is charged to a predetermined potential by the charging roller 303 via the polygon mirror 422 and the imaging lens group 424. An electrostatic image is formed. Thereafter, the toner image is developed by the developing roller 302. The toner image forming operation is performed for yellow Y, magenta M, cyan C, and black K at a predetermined timing. On the other hand, the recording paper 32 once stopped by the registration roller pair 407 is fed again to the ETB 409 at a predetermined timing according to the toner image forming operation, and the toner images on the photosensitive drum 305 are sequentially recorded by the transfer roller 430. A color image is formed by transfer onto the paper 32. The color toner image formed on the recording paper 32 is conveyed to a fixing device 431, heated and pressed by a fixing roller 433 and a pressure roller 434 heated to a predetermined temperature, and fixed on the recording paper, and then discharged from the fixing paper. The paper is discharged out of the image forming apparatus 401 by the roller pair 435.

  When the power is turned off, the pressure applied to the fixing roller 433 and the pressure roller 434 is reduced using a separation mechanism (not shown) under the control of the printer control CPU 207. The separation control described above prevents the rubber deformation of the pressure roller when it is not used for a long time.

  Further, when the power is turned on, the separation mechanism (not shown) is released to bring the fixing roller 433 and the pressure roller 434 into contact with each other, and a predetermined pressure is applied between the fixing roller 433 and the pressure roller 434.

  The discharged recording paper 32 is transported to the optional paper discharge unit 801 via the optional transport unit 701. In the optional paper discharge unit 801, the recording paper 32 is discharged to a paper discharge tray 806 every predetermined number of sheets.

  Next, the operation of the option image scanner will be described. After the document 932 is set on the document transport unit 930, the operation panel selects the copy mode or the scanner mode that only converts the read data into an electronic file.

  When the copy mode is selected, the document transport motor 902 transports the document 932 to the document reading unit 931 at a predetermined timing. Then, the exposure unit 904 is moved horizontally by the scanner drive motor 903 to irradiate the original 932 with light from the exposure unit 905. Reflected light from the document is received by the light receiving device 910 via the mirror 906 and the mirrors 908 and 909 in the reflecting means 907, and the received light signal is transmitted to the image scanner controller unit 940. The image scanner controller unit 940 converts the received signal into image data and transmits it to the engine controller 201. Thereafter, image formation is performed in the same manner as image formation from the host computer 441.

  On the other hand, when the scanner mode is selected, the image scanner controller unit 940 converts the received signal into an electronic file in a predetermined file format and transmits it to the host computer 441 via the reception control IC 440.

  Normally, the operation of the option image scanner operates independently of the image forming operation of the color laser printer 701.

  FIG. 1 is a diagram for explaining the image forming apparatus in this embodiment in more detail.

  Reference numeral 202 denotes a power source, 201 denotes an engine controller, and 203 denotes a cooling fan. Reference numeral 205 denotes a 3.3V power supply circuit that generates 3.3V from the AC power supply, and 204 denotes a 24V power supply circuit that generates 24V from the AC power supply and supplies power to drive system loads such as the DC brushless motor 451 and the cooling fan 203. The 24V power circuit 205 is ON / OFF controlled by the output from the printer control CPU 207 P1.

  The image forming apparatus according to the present invention has a configuration in which the output of the cooling fan 203 can be adjusted by the printer control CPU 207. The cooling fan 203 receives a voltage value obtained by subtracting the collector-emitter voltage of the transistor 209 from 24V. Therefore, by controlling the collector-emitter voltage of the transistor 209, the output of the cooling fan 203 can be controlled. This control is performed using P2 which is an A / D conversion port of the printer control CPU 207 and P3 which is a PWM control port. Specifically, the collector-emitter voltage of the transistor 209 is monitored by the value P2 which is an A / D conversion port of the print control CPU 207, by dividing the value by the resistors 212 and 213. Then, the ON duty of the pulse output from the PWM control port P3 is controlled so that the voltage value of P2 becomes a specified value. The pulse output from the PWM control port P3 is smoothed by the resistor 210 and the capacitor 211 and applied between the base and emitter of the transistor 209, and as a result, the collector and emitter of the transistor 209 are controlled.

  The control from the end of printing of the image forming apparatus in this embodiment to the transition to the energy saving mode will be described below using the flowchart of FIG.

First, in step S201, print end processing is performed. Thereafter, it is determined whether the time (energy saving mode transition time) from the end of printing set by the user to the transition to the energy saving mode is within 5 to 15 minutes. If it is between 5 and 15 minutes, in step S203, the printer control CPU 207 controls the ON duty of the pulse output from P3 to be 100%. In that case, the collector-emitter voltage of the transistor 209 decreases to the saturation voltage, and the cooling fan 203 rotates at the fastest rotational speed. Thereafter, in S207, it is determined whether or not the standby state has continued for the energy saving mode transition time set by the user. If it is determined that the standby state has continued, energy saving mode transition processing is performed in S210. The contents of the energy saving mode transition process are as follows.
The control parameter of the image forming apparatus that controls the separation between the fixing roller 433 and the pressure roller 434 is saved in a nonvolatile memory in the printer control CPU 207.
The 24V power supply circuit 205 is turned off by setting P1 of the printer control CPU 207 to Low.

  On the other hand, if it is determined in S202 that the energy saving mode transition time has not entered between 5 minutes and 15 minutes, it is determined in S204 whether it has entered between 15 minutes and 25 minutes. If it is determined in S205 that the energy saving mode transition time is between 15 minutes and 25 minutes, control is performed so that the input voltage of P2 of the printer control CPU 207 is 0.75 volts. In that case, when the resistance is 7 kΩ and the resistance is 1 kΩ, the collector-emitter voltage of the transistor 209 is 6 V, and a voltage of 18 volts is applied to the cooling fan 203. Thereafter, in S208, it is determined whether or not the standby state has continued for the energy saving mode transition time set by the user. If it is determined that the standby state has continued, the energy saving mode transition processing is performed in S210.

  On the other hand, if it is determined in S204 that it is not within 15 to 25 minutes, the printer control CPU 207 determines that the energy saving mode transition time is 25 minutes or more, and the input of P2 of the printer control CPU 207 is performed in S206. Control the voltage to 1.5 volts. In this case, a voltage of 12 volts is applied to the collector-emitter voltage of the transistor 209 and the cooling fan 203, and the cooling fan 203 rotates at the lowest rotational speed. Thereafter, in S209, it is determined whether or not the standby state has continued for the energy saving mode transition time set by the user. If it is determined that the standby state has continued, the energy saving mode transition processing is performed in S210.

  As described above, in this embodiment, the control for adjusting the output of the cooling fan in the standby state is performed according to the time from the end of printing set by the user to the transition to the energy saving mode. By performing this control, when the energy saving mode transition time is short, the internal temperature can be reliably lowered to a specified value or less when the energy saving mode is shifted by increasing the number of rotations of the cooling fan. As a result, it becomes possible to quickly shift to the energy saving mode, and the power consumption can be reduced.

  Further, when the energy saving mode transition time is long, the noise in the standby state can be reduced by lowering the number of rotations of the cooling fan.

[Example 2]
In this embodiment, control is performed to adjust the output of the cooling fan in the standby state in accordance with the in-machine temperature at the end of printing and the energy saving mode transition time. The in-machine temperature at the end of printing is estimated by the print control CPU. In addition, since the principal part structure in a present Example is the same as Example 1, description is abbreviate | omitted.

  In this embodiment, in order to estimate the internal temperature in the vicinity of the cartridge 410 of the printer, data relating to the internal temperature as shown in FIGS. 3 and 4 is stored in the memory of the printer control CPU 207. FIG. 3 shows the relationship between the number of prints and the internal temperature, and FIG. 4 shows the relationship between the elapsed time in the standby state and the internal temperature with respect to each output of the cooling fan 203. For example, after printing 100 sheets, the internal temperature when the cooling fan 203 is rotated at high speed for 30 minutes is estimated to be about 28.7 ° C. as shown in FIG.

  The control from the end of printing of the image forming apparatus in this embodiment to the transition to the energy saving mode will be described below using the flowchart of FIG.

  First, in step S601, print end processing is performed. Thereafter, in S602, the estimated value of the internal temperature at the end of printing is read, and the transition time to the energy saving mode after the end of printing set by the user in S603 is read. Based on the information read in S602 and S603, the voltage target value of the P2 port of the printer control CPU 207 is calculated in S604 according to Table 1. For example, if the in-machine temperature is 40 ° C and the energy saving mode transition time is 20 minutes, the voltage target value of the P2 port is 1.5V. In step S605, the printer control CPU 207 controls the ON duty of the PWM control port P3 so that the voltage value of the P2 port becomes 1.5V.

  In S606, it is determined whether or not the standby state has continued for the energy saving mode transition time set by the user. If it is determined in S606 that the energy saving mode transition time is reached, an energy saving mode transition process is performed in S607. The contents of the energy saving mode transition process are as follows.

  The fixing roller 433 and the pressure roller 434 are controlled to be separated.

The control parameters of the image forming apparatus are saved in a nonvolatile memory inside the printer control CPU 207.
The 24V power supply circuit 205 is turned off by setting P1 of the printer control CPU 207 to Low.

  As described above, in this embodiment, the control for adjusting the output of the cooling fan in the standby state is performed according to the in-machine temperature set by the user at the end of printing and the time from the end of printing to the transition to the energy saving mode. Further, the temperature inside the apparatus at the end of printing is estimated by the printer control CPU. With the control of the present embodiment, it becomes possible to more optimally control the output of the cooling fan in the standby state, and further reduction in power consumption and noise can be realized.

[Example 3]
In this embodiment, control is performed to adjust the output of the cooling fan in the standby state in accordance with the in-machine temperature at the end of printing and the energy saving mode transition time. Further, the temperature inside the apparatus at the end of printing is measured by a temperature detection element arranged inside the printer. In addition, since the principal part structure in a present Example is the same as Example 1, description is abbreviate | omitted.

  FIG. 7 is a block diagram illustrating a control unit of the image forming apparatus according to the present exemplary embodiment. A thermistor 215 for measuring the in-machine temperature and a resistor 214 for supplying a current to the thermistor 215 are added in the vicinity of the cartridge 410 from FIG. 1 described in the first embodiment. The thermistor 215 is an NTC thermistor, and the resistance value decreases as the temperature increases. FIG. 8 shows the characteristics of the thermistor 215 used in this embodiment. 3.3V is divided by the resistor 214 (4.7kΩ) and the thermistor 215, and the temperature is measured by reading the voltage value using P4 which is the A / D conversion port of the printer control CPU207. FIG. 9 shows the relationship between the machine temperature and the voltage value of P4.

  The control from the end of printing of the image forming apparatus in this embodiment to the transition to the energy saving mode will be described below using the flowchart of FIG.

  First, in step S1001, print end processing is performed. After that, after the end of printing set by the user in S1002, the transition time T1 to the energy saving mode is read, and the voltage value of P4 of the printer control CPU 207 is read in S1003. Based on the information read in S1002 and S1003, the voltage target value of the P2 port of the printer control CPU 207 is calculated in S1004 according to Table 2. For example, if the energy saving mode transition time is 15 minutes and the voltage value of P4 is 1.7V, the voltage target value of the P2 port is 1.5V. In step S1005, the printer control CPU 207 controls the ON duty of the PWM control port P3 so that the voltage value of the P2 port becomes 1.5V.

  In this embodiment, by correcting the fan output every minute, control is performed to ensure that the in-machine temperature reaches the target value in the energy saving mode. Specifically, one minute is measured in S1006, and after one minute has elapsed, a value obtained by subtracting one minute from T1 indicating the time until transition to the energy saving mode in S1007 is stored again as T1. In S1008, it is determined whether or not the time until the energy saving shift has become 0 minute. If it is not 0 minute, the process returns to S1003 to adjust the output of the fan 203 according to the values of P4 and T1. On the other hand, when it is determined in S1008 that the energy saving transition time is 0 minute, the energy saving mode transition processing is performed in S1009. The contents of the energy saving mode transition process are as follows.

  The fixing roller 433 and the pressure roller 434 are controlled to be separated.

  The control parameters of the image forming apparatus are saved in a nonvolatile memory inside the printer control CPU 207.

  The 24V power supply circuit 205 is turned off by setting P1 of the printer control CPU 207 to Low.

  As described above, in this embodiment, the control for adjusting the output of the cooling fan in the standby state is performed according to the in-machine temperature set by the user at the end of printing and the time from the end of printing to the transition to the energy saving mode. The internal temperature at the end of printing is performed by monitoring a temperature detection element arranged in the printer. With the control of the present embodiment, it becomes possible to more optimally control the output of the cooling fan in the standby state, and further reduction in power consumption and noise can be realized.

[Example 4]
In this embodiment, the user can select either “energy saving priority mode” or “low noise priority mode”, and performs control to adjust the output of the cooling fan in the standby state according to the selected result. In addition, since the principal part structure in a present Example is the same as Example 1, description is abbreviate | omitted.

  The control from the end of printing to the transition to the energy saving mode in this embodiment will be described with reference to the flowchart of FIG.

  First, a print end process is performed in S1101. Thereafter, in S1102, it is determined whether the user has selected “energy saving priority mode” or “low noise priority mode”. If it is determined in S1102 that “energy saving priority mode” is selected, the transition time from the end of printing to the energy saving mode is set to 5 minutes in S1003, and P2 of the printer control CPU 207 is set so that the cooling fan 203 rotates at low speed. Control the voltage to 0V. Specifically, in order to control the output of the fan 203, the ON duty of the pulse output from P3 is controlled while monitoring the voltage of P2. After that, when it is determined in S1105 that the standby state has continued for 5 minutes, a transition process to the energy saving mode is performed in S1009. The contents of the energy saving mode transition process are as follows.

  The fixing roller 433 and the pressure roller 434 are controlled to be separated.

The control parameters of the image forming apparatus are saved in a nonvolatile memory inside the printer control CPU 207.
The 24V power supply circuit 205 is turned off by setting P1 of the printer control CPU 207 to Low.

  On the other hand, if the user selects “Low noise priority mode” in S1102, the transition time from the print end to the energy saving mode is set to 20 minutes in S1106, and the printer control is performed so that the cooling fan 203 rotates at a low speed in S1107. The voltage of P2 of CPU207 is controlled to 1.5V. Specifically, in order to control the output of the fan 203, the ON duty of the pulse output from P3 is controlled while monitoring the voltage of P2. After that, when it is determined in S1108 that the standby state has continued for 20 minutes, a transition process to the energy saving mode is performed in S1109.

  As described above, in this embodiment, the user can select either the “energy saving priority mode” or the “low noise priority mode” and perform control for adjusting the output of the cooling fan in the standby state according to the selected result. Do. By this control, the state of the image forming apparatus during standby can be selected according to the user's preference, and usability can be improved.

201 Engine control board 202 Power supply unit 204 Drive power supply 205 Control power supply 207 Printer control CPU
208 Cooling fan 209 Transistor 210 Resistor 211 Capacitor 212 Resistor 213 Resistor 214 Resistor 215 Thermistor 304 Developing roller 305 Photosensitive drum 401 Color laser printer 409 Electrostatic adsorption transfer belts 410Y, 401M, 401C, 401K Process cartridges 420Y, 420M, 420C, 420K Scanner unit 421Y, 421M, 421C, 421K Laser unit 431 Fixing device 432 Heating heater 433 Fixing roller 434 Pressure roller 440 Video controller 441 Host computer 451, 452, 453 DC brushless motor 901 Option image scanner 904 Exposure unit 930 Document transport 931 Document reading unit 940 Image scanner controller unit

Claims (8)

A cooling device for cooling the interior of the image forming apparatus;
Cooling output adjusting means for adjusting the output of the cooling device;
Storage means for storing time from the end of the image forming operation to the transition to the energy saving state,
A standby state waiting for an image forming operation;
In the image forming apparatus having an energy saving state with lower power consumption than the standby state,
An image forming apparatus, wherein the output of the cooling device in the standby state or the energy saving state is changed according to the time stored in the storage unit. 2. The image according to claim 1, wherein when the time stored in the time storage means is shorter than a predetermined value, the output of the cooling device in the standby state is set to a higher output than a predetermined output. Forming equipment. 2. The control according to claim 1, wherein when the time stored in the time recording unit is longer than a predetermined value, the output of the cooling device in the standby state is controlled to be lower than a predetermined output. The image forming apparatus described. A cooling device for cooling the interior of the image forming apparatus;
Cooling output adjusting means for adjusting the output of the cooling device;
In-machine temperature predicting means for predicting the in-machine temperature of the image forming apparatus;
Storage means for storing time from the end of the image forming operation to the transition to the energy saving state,
A standby state waiting for an image forming operation;
In the image forming apparatus having an energy saving state with lower power consumption than the standby state,
The output of the cooling device in the standby state or the energy saving state is changed according to the in-machine temperature at the end of image formation estimated by the in-machine temperature prediction unit and the time recorded in the storage unit. Image forming apparatus. A control unit that controls the image forming apparatus;
Temperature rise information related to the rise in the in-machine temperature in the operating state of the image forming apparatus;
In the image forming apparatus having the temperature decrease information related to the decrease in the in-machine temperature in the standby state of the image forming apparatus, the in-machine temperature predicting means uses the temperature increase information and the temperature decrease information by the control unit. 5. The image forming apparatus according to claim 4, wherein the image forming apparatus predicts the image quality. A cooling device for cooling the interior of the image forming apparatus;
Cooling output adjusting means for adjusting the output of the cooling device;
In-machine temperature detection means for detecting the in-machine temperature of the image forming apparatus,
Storage means for storing time from the end of the image forming operation to the transition to the energy saving state,
A standby state waiting for an image forming operation;
In the image forming apparatus having an energy saving state with lower power consumption than the standby state,
The output of the cooling device in the standby state or the energy saving state is changed according to the in-machine temperature at the end of image formation measured by the in-machine temperature detection unit and the time recorded in the storage unit. Image forming apparatus. A cooling device for cooling the interior of the image forming apparatus;
Cooling output adjusting means for adjusting the output of the cooling device;
A standby state waiting for an image forming operation;
In the image forming apparatus having an energy saving state with lower power consumption than the standby state,
The user can select the output of the cooling device in the standby state or the energy saving state,
An image forming apparatus characterized by changing a time from the end of an image forming operation to the transition to the energy saving state according to a result selected by a user. A cooling device for cooling the interior of the image forming apparatus;
Cooling output adjusting means for adjusting the output of the cooling device;
A standby state waiting for an image forming operation;
In the image forming apparatus having an energy saving state with lower power consumption than the standby state,
The mode in which the output of the cooling device in the standby state is high and the time from the end of the image forming operation to the transition to the energy saving state is shortened, or the transition to the energy saving state from the end of the image forming operation. An image forming apparatus characterized in that a user can select one of modes in which the time until the operation is long and the output of the cooling device in the standby state is low.