JP2002304086A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus where detailed energy conservation control can be realized. SOLUTION: In the image forming apparatus provided with a fixing roll integrated with a heater and a press roll that is in a pressurized contact with the fixing roll, a heater is not lit by not carrying out feeding of power to a fixing unit between pieces of transfer paper.

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 such as a copying machine, a facsimile, and a printer.

[0002]

2. Description of the Related Art FIG. 1 shows an example of an image forming apparatus of the same type as that of the present invention, which is common to the embodiments of the present invention. The transfer paper is fed from the paper feeding unit 1 and temporarily waits in the registration unit 2. On the other hand, document information of the document read by the scanner unit 3 is latently formed on the photoconductor 5 by the writing unit 4, and the toner is developed by the developing unit 6.

The transfer paper waiting at the registration unit 2 is fed in time with the toner image developed on the photoreceptor 5, and the transfer unit transfers the toner image on the photoreceptor 5 onto the transfer paper. Is done. The transfer sheet onto which the toner image has been transferred is conveyed to the fixing unit 8, heat-fused and fixed by the fixing unit 8 controlled at a predetermined temperature, and discharged outside the apparatus through the discharge unit 9.

FIG. 2 shows a schematic structure of a main part including a fixing unit 8 which is also used in the above-mentioned image forming apparatus. The fixing unit 8 includes upper and lower fixing rollers 34 and 35 having heat source lamps 32 and 33 therein. A thermistor 36 for detecting a surface temperature of the fixing rollers 34 is brought into contact with the fixing rollers 34 and 35. Temperature information for controlling the surface temperature of the sheet to the required fixing temperature.

[0005]

Generally, in such an image forming apparatus, the ratio of the power consumption of the fixing roller to the energy consumption of the entire apparatus is very large, which is a great obstacle to energy saving. Has become. Therefore, it has been demanded to reduce such power consumption, and various attempts have been made to control the temperature of the fixing roller as means for that purpose, but no effective means has been provided.

Accordingly, an object of the present invention is to effectively reduce the power consumption in place of the above-mentioned conventional ineffective fixing roller temperature control method, and to accurately perform the operation by automatically operating the control member. Accordingly, an object of the present invention is to provide an image forming apparatus capable of reliably realizing energy saving.

[0007]

According to the present invention, there is provided an image forming apparatus comprising: a fixing roller having a built-in heater; and a pressure roller pressed against the fixing roller. The invention described in Item 1 is characterized in that the heater is not turned on without supplying power to the fixing unit between transfer sheets.

According to a second aspect of the present invention, in the first aspect of the present invention, when a sheet is passed from a mode other than the energy saving mode, the leading end of the transfer sheet is fixed to the fixing unit after receiving a job from the controller. It is characterized in that the heater is not turned on until it comes in front of the immediately preceding sensor.

According to a third aspect of the present invention, in the first aspect of the invention, when the last transfer sheet of one job passes through the fixing unit, power is not supplied to the fixing unit. Is what you do.

According to a fourth aspect of the present invention, in the first aspect of the present invention, when the image forming apparatus is in a printing standby state, the fixing temperature is controlled at a lower temperature than when the sheet is passed. %.

According to a fifth aspect of the present invention, in the first aspect of the present invention, the fixing temperature during printing is higher than that during standby, but the duty is set to 100%. is there.

According to a sixth aspect of the present invention, in the first aspect of the present invention, when the last transfer sheet of one job passes through the fixing unit, power is supplied at a duty of 50%. It is assumed that.

According to a seventh aspect of the present invention, in the first aspect of the present invention, when the image forming apparatus is in a printing standby state and a paper passing request is issued when the inside of the apparatus is sufficiently warm,
When the first transfer sheet passes through the fixing unit, the power is not supplied to the fixing unit, and the fixing is performed by preheating during standby.

According to an eighth aspect of the present invention, in the first aspect of the invention, when the inside of the apparatus is not so warm, the odd numbered pages such as the first, third, and fifth pages. When printing on transfer paper, the printing is performed without supplying power.

According to a ninth aspect of the present invention, in the first aspect of the invention, when the inside of the apparatus is sufficiently warm,
When the last transfer sheet of the job passes through the fixing unit, printing is performed without supplying power.

[0016]

Embodiments of the present invention will be described with reference to the drawings. The parts described in the above conventional example are omitted to avoid duplication, and different parts will be mainly described.

FIG. 3 is a block diagram showing the configuration of an embodiment of the image forming section of the present invention. In FIG. 3, reference numeral 11 denotes a laser printer main body, 12 denotes a controller for performing image processing, 1
Reference numeral 3 denotes an engine for forming an image, 14 denotes an engine control board for controlling the engine 13, and 15 denotes an operation panel.
16 is an input / output interface of the engine board, 17
Is a CPU for controlling the entire engine by a program in a program ROM, a mode instruction from the operation panel 15, and a command from the controller 12, a work memory 18 of the CPU 17, and an input buffer (RA) for input data.
M) and 19 are memories (ROM) storing engine control programs, 20 is a non-volatile memory (EEPROM) storing engine error history and contents of mode instructions from the operation panel 15, and 21 is DIP-SW 22 for setting the mode of engine control; 22 is a laser writing unit including an LD and a polygon motor; 23 is a part for controlling an engine sequence of a fixing system, a developing system, and a driving system;
Reference numeral 24 denotes sensors for checking the paper path and sequence status, reference numeral 25 denotes an input / output interface between the host computer and the controller, and reference numeral 26 denotes a host computer for transmitting and receiving data.

FIG. 4 is a diagram of an operation panel on which the user can make various settings. While the image forming apparatus is on standby, the user can enter the user setting mode by pressing the Menu button or the Enter button shown in the figure. The user can set a fixing control mode of the image forming apparatus by executing a command displayed on the liquid crystal screen.

FIG. 5 is an operation flow chart in the state of the fixing operation according to the first embodiment of the present invention in the state of the fixing operation. When the portion without the transfer paper between the rear end of the first transfer paper and the front end of the second transfer paper passes through the fixing unit, the power to the fixing unit is Without supply, the heat source lamps 32 and 33 are not turned on.

FIG. 6 is a flow chart of the operation of the embodiment of the present invention at the time of the fixing operation according to the second aspect of the present invention. If the first transfer sheet of the job enters the fixing unit, the heater is not turned on until the leading edge of the transfer sheet reaches the sensor immediately before the fixing unit after receiving the job from the controller. The fixing control is performed to fix the toner on the transfer paper.

FIG. 7 is a flow chart showing the operation of the embodiment of the present invention at the time of the fixing operation according to the third aspect of the present invention. In this fixing operation, the last transfer sheet of one job is When passing through the fixing unit, the power is not supplied to the fixing unit, the heat source lamps 32 and 33 are not turned on, and the fixing is performed by preheating.

FIG. 8 is an operation flow chart at the time of the fixing operation in the invention according to the fourth, fifth and sixth aspects of the present invention. In the invention according to the fourth aspect, the image forming apparatus is in a print standby state. At the time of medium, the fixing temperature is controlled at a lower temperature than when the sheet is passed, but the duty is set to 50%. According to the fifth aspect of the invention, the control is performed at a higher temperature during printing than during standby, but the power supply is set to a duty of 100%. In the invention according to claim 6, when the last transfer sheet of one job passes through the fixing unit, the power supply of the fixing unit is reduced to the duty 50%.
% Power supply.

FIG. 9 is an operation flow chart at the time of the fixing operation in the invention described in claim 7 of the present invention.
According to the seventh aspect of the present invention, when the image forming apparatus is in a printing standby state and a paper passing request is made when the inside of the apparatus is sufficiently warmed, the first transfer sheet first passes through the fixing unit. When passing, power is not supplied to the fixing unit.

FIG. 10 is a flow chart showing the operation of the fixing device according to the eighth aspect of the present invention at the time of the fixing operation. When printing on a transfer sheet of an odd-numbered page such as the third, fifth, or fifth sheet, printing is performed without supplying power.

FIG. 11 is an operation flow chart at the time of the fixing operation according to the ninth aspect of the present invention. In the ninth aspect of the present invention, when the inside of the apparatus is sufficiently warmed, When the last transfer sheet of one job passes through the fixing unit, printing is performed without supplying power.

[0026]

As described above, the present invention is directed to an image forming apparatus having a fixing roller having a built-in heater and a pressure roller pressed against the fixing roller. Since power is not supplied to the fixing unit between sheets and the heater is not turned on, energy saving can be achieved.

According to a second aspect of the present invention, when a sheet is fed from a mode other than the energy saving mode, the heater is turned on after receiving a job from the controller until the leading edge of the transfer sheet comes in front of the sensor immediately before the fixing unit. Since the light is not turned on, there is an effect that finer energy saving control can be realized.

According to the third aspect of the present invention, when the last transfer sheet of one job passes through the fixing unit, power is not supplied to the fixing unit, so that finer energy saving control can be realized. There is an effect that can be.

According to a fourth aspect of the present invention, when the image forming apparatus is in a printing standby state, the fixing temperature is controlled at a lower temperature than when the sheet is passed, but the duty is set to 50%, so that an energy saving effect is realized. In addition, there is an effect that fine-grained energy saving fixing control can be realized.

According to a fifth aspect of the present invention, the fixing temperature during printing is higher than that during standby, but the duty is set to one.
Since it is set to 00%, there is an effect that quick fixing control can be performed, and the start of paper passing from the standby state can be accelerated.

According to a sixth aspect of the present invention, when the last transfer sheet of one job passes through the fixing unit, power is supplied at a duty of 50%, thereby realizing an energy saving effect, and providing a fine energy saving. There is an effect that the fixing control can be realized.

According to a seventh aspect of the present invention, when the image forming apparatus is in a printing standby state and a paper passing request is made while the inside of the apparatus is sufficiently warm, the first transfer sheet is fixed. When passing through the unit, fixing is performed by preheating during standby without supplying power to the fixing unit, so that there is an effect that fine energy saving fixing control can be performed.

The invention according to claim 8 is characterized in that, when the inside of the apparatus is not so warm, when printing on the transfer paper of an odd number of pages such as the first, third and fifth sheets,
Since printing is performed without supplying power, there is an effect that fine energy saving control can be performed.

According to the ninth aspect of the present invention, when the inside of the apparatus is sufficiently warm, when the last transfer sheet of one job passes through the fixing unit, printing is performed without supplying power, so that There is an effect that detailed energy saving control can be performed.

[Brief description of the drawings]

FIG. 1 is a front view of an example of an image forming apparatus of the same type as the present invention.

FIG. 2 is a front view of a main part including the fixing unit according to the first embodiment.

FIG. 3 is a block diagram illustrating a configuration of an image forming unit according to the present invention.

FIG. 4 is a diagram of an operation panel on which a user can make various settings.

FIG. 5 is an operation flow chart at the time of a fixing operation in the invention described in claim 1 of the present invention.

FIG. 6 is an operation flowchart at the time of a fixing operation in the invention described in claim 2 of the present invention.

FIG. 7 is an operation flowchart at the time of a fixing operation in the invention described in claim 3 of the present invention.

FIG. 8 is an operation flow chart at the time of a fixing operation in the invention according to the fourth, fifth and sixth aspects of the present invention.

FIG. 9 is an operation flowchart at the time of a fixing operation in the invention described in claim 7 of the present invention.

FIG. 10 is an operation flowchart at the time of a fixing operation in the invention described in claim 8 of the present invention.

FIG. 11 is an operation flowchart at the time of a fixing operation in the invention described in claim 9 of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Paper feed part 2 Registration part 3 Scanner part 4 Writing part 5 Photoconductor 6 Developing part 8 Fixing unit 11 Laser printer main body 12 Controller 13 Engine 14 Engine control board 15 Operation panel 16 Input / output interface 17 CPU 18 Input buffer (RAM) DESCRIPTION OF SYMBOLS 19 Memory (ROM) 20 Non-volatile memory (EEPROM) 21 DIP-SW 22 Writing unit 23 Part responsible for engine sequence 24 Sensors 25 Input / output interface 26 Host computer 31 Fixing unit 32 Heat source lamp 33 Heat source lamp 34 Fixing roller 35 Fixing roller 36 Thermistor

Continued on front page F term (reference) 2H027 DA11 DA41 DA45 DC05 EA12 EA15 ED25 EF04 EF16 2H033 AA32 BB00 CA04 CA05 CA07 CA08 CA22 CA23 CA30 CA32 CA44

Claims (9)

[Claims] In an image forming apparatus having a fixing roller having a built-in heater and a pressure roller pressed against the fixing roller, the heater is not turned on without supplying power to the fixing unit between transfer sheets. An image forming apparatus comprising: 2. When a sheet is fed from a mode other than the energy saving mode, after receiving a job from the controller,
2. The image forming apparatus according to claim 1, wherein the heater is not turned on until the leading edge of the transfer paper comes in front of the sensor immediately before the fixing unit. 3. The image forming apparatus according to claim 1, wherein when the last transfer sheet of one job passes through the fixing unit, power is not supplied to the fixing unit. 4. The image forming apparatus according to claim 1, wherein when the image forming apparatus is in a printing standby state, the fixing temperature is controlled at a lower temperature than when the sheet is passed, but the duty is set to 50%. apparatus. 5. The image forming apparatus according to claim 1, wherein the fixing temperature during printing is higher than that during standby, but the duty is set to 100%. 6. The image forming apparatus according to claim 1, wherein when the last transfer sheet of one job passes through the fixing unit, power is supplied at a duty of 50%. 7. When a paper passing request is issued while the image forming apparatus is in a printing standby state and the inside of the apparatus is sufficiently warm, when the first transfer sheet passes through the fixing unit,
2. The image forming apparatus according to claim 1, wherein fixing is performed by preheating during standby without supplying power to the fixing unit. 8. When the inside of the apparatus is not so warm, when printing on the transfer sheet of an odd-numbered page such as the first, third, or fifth sheet, the printing is performed without supplying power. The image forming apparatus according to claim 1, wherein: 9. When the inside of the apparatus is sufficiently warm, when the last transfer sheet of one job passes through the fixing unit,
The image forming apparatus according to claim 1, wherein printing is performed without supplying power.