JPH02161482A - Image forming device - Google Patents

Abstract

PURPOSE:To save electric power without developing a fixing defect, etc., by starting energizing a heating body after the manual feeding of recording material is detected. CONSTITUTION:The subject device is provided with a paper feeding means 8 which manually feeds the recording material P, a detecting means 7 which detects the recording material P manually fed by the paper feeding means 8, and a control means 40 which starts energizing the heating body 24 in response to the detection of the manual feeding of the recording material P by the detecting means 7. After the manual feeding of the recording material P is detected, the energization of the heating body 24 is started. Thus, an unnec essary standby time is eliminated without developing a fixing defect, etc., and energy can be saved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an image forming apparatus that includes a manual feeding mechanism and heats and fixes a visible image formed on a manually fed recording material.

[Prior Art] Conventionally, a fixing device used in this type of apparatus uses a heating roller maintained at a predetermined temperature and a pressure roller having an elastic layer that presses against the heating roller. A hot roller fixed fixing method is often used, in which a transfer material on which a toner image is formed is heated while being nipped and conveyed.

A belt fixing system described in US Pat. No. 3,578,797 is also known.

[Problems to be Solved by the Invention] However, the above conventional example has the following drawbacks.

(1) Heat roll fixing method - There is a so-called wait time, which is a time when the temperature is raised to a predetermined temperature and image forming operation is prohibited.

■It requires a large amount of electricity because it requires heat capacity.

■Because the roller temperature is high with rotating rollers, special heat-resistant bearings are required.

■The roller is in direct contact with the hands, which may be dangerous and requires protective materials.

■The transfer material is wrapped around the roller due to its constant temperature and curvature.
It becomes AM.

(2) Belt fixing method [Means for solving the problem] The present invention solves the problems of the above-mentioned conventional devices, and particularly improves the standby time and consumption of belt fixing in devices equipped with a manual paper feeding mechanism. It is an object of the present invention to provide an image forming apparatus that can reduce electric power and further reduce internal temperature rise.

According to the present invention, there are provided the following: an image forming means for forming a visible image on a recording material using a developing material; a fixing means for fixing the visible image by heating the recording material with a heating body that generates heat; A paper feeding means for manually feeding paper, a detection means for detecting recording material manually fed by the paper feeding means, and energizing the heating body in response to detection of manual feeding of the recording material by the detection means. By providing a control means for starting the manual feeding of the recording material, energization to the heating element is started after detecting the manual feeding of the recording material, thereby eliminating unnecessary waiting time without causing fixing defects, etc., and saving energy. The goal is to achieve

Further, when manual paper feeding is canceled after a predetermined period of time has elapsed after the start of energization to the heating element, the energization to the heating element is stopped, thereby achieving further energy savings.

[Example] Hereinafter, the present invention will be described in detail based on the accompanying drawings.

First, the general structure of the image forming apparatus of this embodiment will be explained based on FIG.

Reference numeral 1 denotes an original mounting table 114 made of a transparent member such as glass, which scans the original by reciprocating in the direction of arrow a. A short-focus, small-diameter imaging element array 4 is arranged directly below the document placement table, and the document image placed on the document R placement table is slit-exposed onto the photosensitive drum 5 by the illumination lamp 2. Note that this photosensitive drum rotates in the direction indicated by the arrow. Also, 3 is a charger,
For example, the photosensitive drum 5 coated with a zinc oxide photosensitive layer or an organic semiconductor photosensitive layer is uniformly charged. The photosensitive drum 5, which has been uniformly charged by the charger 3, is subjected to image exposure by the element array 4, and an electrostatic latent image is formed. This electrostatic latent image is visualized by a developing device 6 using toner made of a resin or the like that softens and melts when heated.

On the other hand, the sheet P is inserted according to the manual paper feed guide 8 and is sent to the position of the registration roller 10 by the paper feed roller 9. Here, 7 is a paper feed sensor that detects a fed sheet. Next, the sheet P is fed onto the photosensitive drum 5 by a pair of registration rollers 10 that are rotated while being pressed against each other in the vertical direction in synchronization with the image on the photosensitive drum 5. Then, the toner image formed on the photosensitive drum 5 is transferred onto the sheet P by the transfer discharger 11. Thereafter, the sheet P separated from the photosensitive drum 5 by a known separating means is
The paper is guided to the fixing device 14 by the conveyance guide 13, subjected to heat fixing processing, and then discharged onto the tray 15-L. Note that after the toner image is transferred, residual toner on the photosensitive drum 5 is removed by a cleaner 12.

FIG. 2 shows an enlarged view of the fixing device 14 of this embodiment. 2
4 is a low heat capacity linear heating element that is fixedly supported on the device, and as an example, has a thickness of 1.0 mm, a width of 6 mm, and a longitudinal length of 240 m.
The resistive material 26 is coated on an alumina substrate 25 having a width of 1.5 mm, and electricity is applied from both ends in the longitudinal direction. The energization is
For example, with a DClooV pulse waveform having a period of 20 m5 ec, pulses are given by varying the pulse width in accordance with the desired temperature and energy release amount controlled by the temperature measuring element 22. Approximate pulse width is 0.5mS e C~
5 mSec.

The fixing film 21 moves in the direction of the arrow in the figure while coming into contact with the heating body 24 whose energy and temperature are controlled in this manner. An example of this fixing film is a heat-resistant film with a thickness of 20 μm at °C, such as polyimide, polyetherimide, PE.
3% PFA with PTFE and P at least on the image contact side
A 10 μm release layer made of fluororesin such as AF with a conductive material added.
It is an endless film coated with M. Generally the total thickness is less than 100 μm, preferably less than 40 μm. The film is driven by the drive roller 20 and the drive roller 23 and tension, and moves in the direction of the arrow without wrinkles. Reference numeral 29 denotes a pressure roller having a rubber elastic layer with good mold releasability such as silicone rubber, which presses the heating body through the film with a total pressure of 4 to 7 kg and rotates in pressure contact with the film. The unfixed toner 27 on the transfer material 28 is guided to the fixing section by the entrance guide 30 and is heated as described above to obtain a fixed image.

Although the case where the fixing film is an endless belt has been described above, the fixing film may also be a film with ends as shown in FIG.

Image forming devices include copiers, printers, and fax machines.
This device can be applied to all types of fixing devices that form images using toners such as the above.

Next, FIG. 4 shows a schematic diagram of a circuit for performing electrical control. Here, 40 is a microcomputer, and the paper feed sensor 7 is connected to its input terminal INI. Further, a fixing temperature control signal is output from the 0UT1 terminal, and is connected to a fixing temperature control circuit 42 to control the temperature of the heating body 24. A motor control signal for controlling ON10FF of the main motor 41 that drives the fixing device and the main body is output from the 0UT2 terminal. Although not shown, the microcomputer 40 is equipped with terminals for outputting other human input signals and output signals necessary for the operation of the image forming apparatus. It has a built-in ROM and RAM in which the device's operation sequence program and the like are programmed.

FIG. 5 shows a schematic flowchart of the operation sequence program for Kinob & Example. This program is programmed into the built-in ROM in the microcomputer 40 described above, and after the device is operated, step 1 is executed from the start. In step 1, it is determined whether the paper feed sensor 7 is ON or not. If it is not ON, the process moves to step 2, and the process enters a standby state and returns to step 1. Further, if the paper feed sensor is ON in step 1, the process moves to step 3. In step 3, in order to start the image forming operation, first the motor 41 is turned on, then temperature control of the heating element 24 (hereinafter referred to as fixing temperature control) is started, preparations are made before image formation, and the process moves to step 4. In step 4, it is determined again whether the paper feed sensor 7 is ON or not. If it is not ON, it is determined that the sheet fed by the carrier has been removed midway, and the process proceeds to step 6. Transition. In step 6, fixing temperature control is stopped,
The motor 41 is stopped and the process moves to step 2 to enter a standby state. Also, in step 4, the paper feed sensor 7
If is ON, the process moves to step 5 and a series of image forming operations are performed. After the image forming operation is completed,
Return to step 1 and enter the standby state.

As explained above, when manually feeding paper, by starting the fusing temperature adjustment after manual feeding is detected, it is possible to stop the fusing temperature adjustment at times other than image formation, such as during standby, thereby reducing waste. Energy saving is possible because energy consumption is eliminated.

Also, after the preparation of the image forming surface is completed, that is, after a predetermined period of time has elapsed, the state of the paper feed sensor is checked again, and if manual paper feeding is canceled at this time, the system returns to standby mode and stops fixing temperature adjustment. This makes it possible to eliminate wasteful energy consumption and save energy.

[Other Embodiments] FIGS. 6 and 7 show the operation sequence of a second embodiment of the present invention. The main body configuration and electrical control configuration are the same as those in the first embodiment, and their explanation will be omitted here.

First, after the present device operates, step io in FIG. 6 is executed. Here, the RAM and the like in the microcomputer 40 are initialized, and at the same time, a timer interrupt is also set, which interrupts at fixed time intervals. Next, the process moves to step 11, where it is determined whether or not the operation request flag is set. As will be described later, the motion request flag is set when it is detected that a sheet is manually fed when an image forming operation is not in progress. If the action request flag is not set here, return to step 11; if the action requested flag is set, step 1
Move to 2. In step 12, the motor 41 is turned on.
L. Go to step 13. In step 13, preparations are made before image formation, and the process moves to step 14. Step 1
In step 4, it is determined whether or not the operation request flag is set. If the operation request flag is not set, the process moves to step 16, the device returns to standby state, and then the motor 41 OF
F and return to step 11. Also, step 14
If the operation request flag is set in step 15, the image forming flag is set and the image forming operation is performed.After the image forming operation is completed, the image forming flag is reset and the remaining portion of the photosensitive drum 5 is removed. After image formation post-processing such as post-rotation for potential removal, the process proceeds to step 17. In this embodiment, the image forming operation is performed by detecting the ejection of the sheet by a not-shown hinger on the ejection side of the fixing device. Next, in step 17, it is determined whether or not the operation request flag is set. If the operation request flag is set, the process returns to step 13; if it is not set, the process proceeds to step 18, where the motor 41 is set to 0FFL, and step 11
Go back and repeat the above steps.

Next, FIG. 7 shows a flowchart of the timer interrupt processing in which interrupts occur at regular time intervals as described above. First, starting from the population, step 18 is executed. Here, it is first determined whether or not the image formation flag is set, and if the image formation flag is set, the process moves to the exit of step 23 and returns to the main program. Further, if the image formation flag is not set in step 18, the process moves to step 20. In step 20, the paper feed sensor 7 is
It is determined whether or not the paper feed sensor 7 is ONL, and if the paper feed sensor 7 is ONL, the process moves to step 21. In step 21, fixing temperature control is first started, then an operation request flag is set, and the process moves to step 23. Also, in step 20, the 5 paper feed sensor 7 is set to O.
If not, the process moves to step 22. In step 22, the fixed temperature control is stopped, and then the operation request flag is reset, and the process proceeds to step 23, whereupon the process returns to the main program in the same manner as described above, and the fixing temperature control is started after paper feeding is detected. In addition, by stopping the fixing temperature control when the manual paper feeding is canceled within a predetermined time, it is possible to further reduce wasteful energy consumption, and the energy saving effect is as explained above. According to the present invention, a heating element heats the recording material to heat and fix the visible image formed on the manually fed recording material, and further detects the manual feeding of the recording material. After that, electricity is started to be applied to the heating element, so that it is possible to save electricity and eliminate unnecessary waiting time without causing fixing failure or the like.

Furthermore, if manual paper feeding is canceled after a predetermined period of time has passed after the start of energization to the heating element, further power saving is possible by stopping the energization to the heating element, and It becomes possible to suppress the temperature.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an image forming apparatus that is an embodiment of the present invention, FIG. 2 is a sectional view of a fixing device using an endless film, and FIG. 3 is a sectional view of a fixing device using an edged film. FIG. 4 is a block diagram showing the control unit of the image forming apparatus. FIG. 5 is a flowchart showing an outline of control in the first embodiment. FIGS. 6 and 7 are outlines of control in the second embodiment. This is a flowchart showing the following. In the figure, 1 is a document placement table, 2 is an illumination lamp, 3 is a charger, and 4
1 is a short focus small diameter imaging element array, 5 is a photosensitive drum, 6 is a developing device, 7 is a paper feed sensor, 8 is a manual paper feed guide, 9 is a paper feed roller, 10 is a registration roller, 11 is a transfer discharger, 12 13 is a cleaner, 13 is a conveyance guide, 14 is a fixing device, 15 is a paper discharge tray, P is a transfer paper which is a recording material, 20 is a drive roller, 21 is a fixing film, 2
2 is a temperature measuring element, 23 is a driven roller, 24 is a heating element, 2
5 is an alumina substrate, 26 is a resistance material, 29 is a pressure roller, and 30 is an artificial guide. man's mouth

Claims (2)

[Claims] (1) An image forming means that forms a visible image on a recording material using a developing material, a fixing means that fixes the visible image by heating the recording material with a heating element that generates heat, and manually feeds the recording material. a detection means for detecting recording material manually fed by the paper feeding means; and a detection means for starting energization of the heating body in response to detection of manual feeding of the recording material by the detection means. An image forming apparatus comprising: a control means; (2) In the image forming apparatus according to claim 1, the control means starts energizing the heating body in response to the detection of manual feeding of the recording material by the detection means, and then An image forming apparatus characterized in that when manual feeding of the recording material is canceled within a predetermined time period, power supply to the heating element is stopped.