JPH03231784A - Printing device - Google Patents

Abstract

PURPOSE:To remove toner on recording paper when a print-recorded picture is required to be corrected by providing a mode for carrying out normal fixing and a mode for carrying out fixing with such the quantity of heat and pressure that a fixing rate is lowered. CONSTITUTION:A normal mode switch 8a, pencil mode switch 8b and a refixing mode switch 8c are provided on a panel switch 8. When the normal mode switch 8a is selected, printing is carried out by a normal electrophotographic method. When the pencil mode switch 8b is selected, the surface temperature of a fixing roller 1 is controlled to be low and the recorded image printed in this mode can be easily erased by an eraser. Thus, such a printing device where a correctable print-recorded picture can be obtained is easily realized. Furthermore, the fixability of this print-recorded picture can be improved by refixing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the field of information processing and the field of office equipment, and more particularly to a printing device.

[Prior Art] In recent years, in the field of information processing equipment, the use of printing devices generally called page printers has rapidly increased. Most of these printing devices use electrophotographic principles to print by transferring toner onto recording paper and fixing it using heat or pressure.These printing devices have features such as low noise, high speed printing, and high print quality. It has become widely used because it can be realized.

[Problems to be Solved by the Invention] The toner used in such printing devices has a structure in which a coloring material such as carbon is dispersed in a thermoplastic resin base material. The toner is fixed on the recording paper by melting the toner using heat or pressure in a fixing device and permeating it into the fibers of the recording paper. Therefore, although the toner that is first fixed on the recording paper adheres firmly and has excellent preservation of the printed recorded image, it is difficult to remove the toner on the recording paper when the printed recorded image needs to be corrected. It was extremely difficult.

[Means for Solving the Problems] In order to solve the above-mentioned problems, in the present invention, the fixing conditions such as the temperature or pressure of the fixing device can be selectively adjusted to a plurality of setting conditions. Furthermore, if necessary, it is also possible to run the recording paper through the printing process under normal fixing conditions without transferring toner onto the recording paper.

[Function] In addition to fixing conditions that result in normal fixing, it is also possible to set fixing conditions that result in poor fixing performance. By performing fixing under these conditions, the adhesion force of the toner to the recording paper is reduced, and the printed recorded image is Toner can be easily removed during correction. Also,
In order to improve the shelf life of the corrected printed image, the corrected recording paper may be passed through the fixing process again under normal fixing conditions to perform only re-fixing, thereby increasing the adhesion of the toner.

[Example] A detailed description of the present invention will be given according to examples.

Although there are several possible printing principles and methods for a printing device to which the present invention can be applied, an explanation will be given by taking an electrophotographic printing device as an example of the most widely used method.

FIG. 1 is a schematic configuration diagram centered on a fixing device of a printing apparatus according to an embodiment of the present invention. The fixing device includes a fixing roller 1, a pressure roller 2, and a halogen lamp 3. The fixing roller 1 is made of, for example, a metal pipe, and has a fluorine-based resin layer provided on its surface. This is to prevent the toner from being transferred onto the surface of the fixing roller l when the toner on the recording paper contacts the surface of the fixing roller 1 and is fixed. The pressure roller 2 has a structure in which a viscoelastic layer 2b such as rubber or sponge is provided on a metal core 2a.

The pressure roller 2 is pressed against the fixing roller 1 by a pressure biasing means such as a spring. The halogen lamp 3 has a rod-like shape, and emits light and generates heat when energized to heat the fixing roller 1.

Power is supplied to the halogen lamp 3 from a fixing power source 5.

A 5SR (solid state relay) 4 turns the power supply 5 on and off. The operation of the 5SR4 is controlled by the control board 6. The thermistor 7 is arranged so as to be in contact with the surface of the fixing roller 1. The surface temperature of the fixing roller 1 is converted into voltage by the thermistor 7. The voltage is sent to the control board 6 as a thermal signal. The control board 6 controls the 5S so that the voltage becomes a predetermined voltage.
The control board 6 turns on and off the halogen lamp 3 by controlling R4 to keep the surface temperature of the fixing roller within a certain range.The control board 6 also controls the motor 9, which is the drive source of the entire printing device, and the laser head 10 for writing. It also performs control.

The panel switch 8 is normally provided at a position on the exterior surface of the printing device that is easy to operate. In this embodiment, the panel switch 8 has at least a normal mode switch 8a, a pencil mode switch 8b, and a refixing mode. switch 8
c.

When the normal mode switch 8a is selected, the printing device performs normal electrophotographic printing. At this time, the surface temperature of the fixing roller 1 is controlled to be around 180 degrees, for example. When the pencil mode switch 8b is selected, the surface temperature of the fixing roller 1 is lowered, for example, by
It is controlled around 40 degrees. The printed image on the recording paper printed in this mode can be easily erased with an eraser and can be handled as if it were an image recorded with a pencil, so it is called the pencil mode. Toner has a structure in which a coloring material such as carbon is dispersed in a thermoplastic resin, and when it is fixed under normal fixing conditions, the thermoplastic resin softens sufficiently and penetrates into the fibers of the recording paper, making it strong. It is firmly established. However, when the fixing temperature is lowered, the thermoplastic resin does not soften sufficiently, resulting in a lower fixing strength of the toner to the recording paper. Therefore, the toner on the recording paper can be easily removed by rubbing it with an eraser, making it possible to correct it. When the re-fixing mode switch 8c is selected, the surface temperature t of the fixing roller 1 becomes the same as in the normal mode. However, the image is not written. This is because printed recorded images created in pencil mode have low fixing strength, so strong fixing is required if you want to preserve them for a long time after correction. Therefore, by passing the recording paper created in the pencil mode through the printing device again in the re-fixing mode, strong fixing is performed.

Figure 2(a) shows the normal mode and re-fixing mode, Figure 2(a)
b) is an energization time diagram showing the energization status of the halogen lamp 3 in pencil mode. The surface temperature of the fixing roller 1 required in each mode can be achieved by changing the energization duty in this manner, setting it to a high duty in the normal mode and re-fixing mode and a low duty in the pencil mode.

"Effects of the Invention" According to the present invention, by making slight changes to conventional printing devices, it is possible to easily realize a printing device that can obtain a print record image that can be corrected. It is also possible to improve the fixability of recorded images, and it is possible to add great value to conventional printing devices.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram centered on a fixing device of a printing apparatus according to an embodiment of the present invention. FIG. 2(a) is a diagram showing the energization time of the halogen lamp in the normal mode and refixing mode in one embodiment of the present invention. FIG. 2(b) is a diagram showing the energization time of the halogen lamp in pencil mode in one embodiment of the present invention. 1... Fixing roller 2... Pressure roller 2a... Core bar 2b... Viscoelastic layer 3... Halogen lamp 4... 5SR (solid state relay) 5...・
- Fixing power supply 6... Control board 7... Thermistor 8... Panel switch 8a... Normal mode switch 8b -... Pencil mode switch 8C... Re-fixing mode switch 9. ...Motor 10...Laser head

Claims (2)

[Claims] (1) In a printing device that fixes toner transferred onto a printing medium using at least one of heat and pressure, there are two modes: a mode for normal fixing, and a mode for heat or pressure that lowers the fixing rate. A printing device characterized by having a mode for performing fixing. 2. The printing apparatus according to claim 1, further comprising a mode in which the printing medium is passed through a fixing process within the printing apparatus under normal fixing conditions without transferring toner onto the printing medium.