JPS60122975A - Toner fixing device - Google Patents

Abstract

PURPOSE:To suppress effectively generation of an uneven fixation, also to obtain a thermal pressure effect without requiring a large heat source, and to improve a fixation by applying an ultrasonic vibration to a fixing pressure roller, and executing a fixation. CONSTITUTION:A toner image is fixed by rollers 20, 21 to a transfer paper 20 to which the toner image has been transferred. In this case, one of the rollers 20, 21 is brought to an ultrasonic vibration by an ultrasonic vibration means 23, and basing on this ultrasonic vibration, the toner image is fixed. As a result, it is suppressed that an uneven fixation is generated, also a thermal pressure effect is obtained without requiring a large heat source, and a fixation can be executed exactly.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a toner fixing device for a copying machine, etc., and in particular to a toner fixing device that applies ultrasonic vibration to a pressurizing body to reliably fix toner to paper. related to things.

[Prior art]

An electrophotographic copying machine is shown in Figure 1.

The surface of the photosensitive drum 1 is uniformly charged by discharge from the charging electrode 2, and a mirror 6° lens 7,
The image of the original between the original platen 3 and the original cover 4 is exposed through the route of the mirror 8 to form a latent image. At this time, the illumination rung 5 illuminates the surface of the document.

In this way, the illumination lamp 5. An optical system consisting of a mirror 6, a lens 7, and a mirror 8 projects the original onto the ram l below the photoreceptor according to the broken line in Figure 1.

As a result, a latent image is formed on the photoreceptor drum.

The latent image formed on the surface of the photoreceptor drum 1 in this way
Toner is supplied from the toner box 9 via the developing sleeve 10 and the latent image is developed, thereby forming a toner image identical to the original on the photoreceptor drum l.

On the other hand, the transfer paper 11 loaded into the copying machine in a cassette is fed out one by one by the paper feed roller 12 as shown by the broken line and onto the transfer electrode 13.

It is superimposed on the surface of the photoreceptor drum l on which the toner image is formed. Then, the back surface of the transfer paper is charged by the discharge charge of the transfer electrode 13, and the electrically charged toner is attracted by the stone and its electric force and moves from the drum surface to the surface of the transfer paper. In this way, the toner image is transferred to the surface of the transfer paper.

The transfer paper on which the toner image has been transferred is peeled off from the photoreceptor drum l, placed on a belt conveyor of a transfer paper transport section 15, and sent to a fixing section 16. At this time, the charges on the transfer paper are neutralized by the one-separation electrode 14.

In the fixing section 16, the toner image is heat-pressed by a heating roller and firmly fixed on the paper.

It is delivered to the discharge section 17.

By the way, after the toner image is transferred to the transfer paper, the photosensitive drum 1 is cleaned of residual toner by the cleaner section 18, and is ready for the ninth copying. In Figure 1, 19 is a motor.

[Problem that the invention seeks to solve]

By the way, in the above-mentioned fixing section, as shown in Figure 2, conventionally, a heating roller HR with a built-in heater and a normal roller R heat and press the transfer paper Pt on which the toner image is attached to fix the toner image on the transfer paper P. How to do it.

As shown in Fig. 3, there is a method in which the toner image is fixed by strongly pressing the paper Pf onto which the toner image is attached by using pressure rollers P and R and a normal four-layer mechanism.

The former heat roll fixing method requires a large heat source to heat the heat roll, and therefore requires a large heat source and is therefore expensive.

Although the latter pressure fixing method has an advantage in terms of cost, it has the problem that insufficient fixing tends to occur due to insufficient or uneven pressure.

[Means for solving problems]

The present invention aims to solve the above-mentioned problems.

By applying ultrasonic vibration to the pressurizing body, pressure fixing is performed without causing insufficient pressure or uneven pressure, and it also generates heat without using a heat source such as a heater to produce a thermal press effect. It is.

As a result, the fixing row uses ultrasonic vibrations to uniformly and strongly press the paper surface, and when applying pressure, the vibration energy is converted into heat and generates heat.

The toner image can be fixed by pressure and heat on the paper.

〔Example〕

Next, a first embodiment of the present invention will be described based on FIG.

In the four parts, 20 is a transfer paper on which the toner image is transferred, 21 is a fixing roller, and a roller shaft 21-1 is constructed at both ends of the fixing roller. An ultrasonic vibrating section 23 is arranged at the roller 2.
2 and presses the transfer paper 2°. One example of the ultrasonic vibration section 23 is tPb(Ti, Zr) Os
(PZT) Ceramic ylx-based ultrasonic transducer 23-1
and an ultrasonic vibration transmitting body 23-2. Now, when the ultrasonic vibrator 23-1 is excited by the oscillator 24, ultrasonic vibration is generated, and this ultrasonic vibration is transmitted to the roller shaft 21-1.
The fixing roller 21t is subjected to ultrasonic vibration in the state indicated by the arrow.

When the transfer paper 20 is delivered near the fixing roller 21 and the roller 22, the oscillator 24 oscillates in response to this, and the ultrasonic transducer 23-1'i is excited. As a result, the ultrasonic transducer 23-1 oscillates ultrasonic waves.

This is transmitted to the fixing roller 21 via the ultrasonic vibration transmitting body 23-2, and the fixing roller 21 evenly and strongly presses against the surface of the transfer paper 20. in this case.

Similar to the principle of ultrasonic welding, vibration energy is converted into heat by applying pressure, so the fixing roller 21
The pressure contact surface generates heat. In this way, the paper surface of the transfer paper 20 is heated and pressed by strong pressure based on ultrasonic vibrations and heat generated on the surface of the fixing roller, and the toner image is reliably fixed on the transfer paper. Become.

Next, a second embodiment of the present invention will be explained with reference to Figure 5.

In FIG. 5, an ultrasonic transmission block 31 is arranged inside the fixing roller 30. On the outside of the horn-shaped portions at both ends of the ultrasonic transmitter 31, there is an ultrasonic oscillator 32 having an ultrasonic transducer 32-1 and a cap 32-2. is measured, and the ultrasonic transducer 32-
1 is excited by an oscillator 33.

λ This ultrasonic transmitter 31 is composed of members having an interval of 7 (λ is the wavelength of the ultrasonic wave) and a radius of 7.

When the transfer paper on which the toner image has been transferred is transferred to the vicinity of the fixing roller 30 and a roller (not shown) (corresponding to 22 in Fig. 4), the first oscillator 33 and 33 operate to generate an ultrasonic oscillator. 32 generates an ultrasonic wave, which causes the ultrasonic transmitter 31 to ultrasonically vibrate the fixing roller 31 in the direction of the arrow and press the transfer paper, and is heated by the heat generation effect on the surface of the fixing roller. Eventually, the toner image is heated and pressed onto the transfer paper and is firmly fixed.

In each of the above embodiments, an example was described in which only one roller vibrates ultrasonically and the other roller uses a normal roller, but it is of course possible to use a roller in which both rollers vibrate ultrasonically. Further, ultrasonic waves having a frequency of about 15 to 50 KHz can be used.

The present invention can of course be used not only for electrophotography but also for fixing toner images in facsimile machines, printers, etc.

〔effect〕

According to the present invention, the fixing pressure roller is vibrated by ultrasonic vibration to effectively suppress and improve the occurrence of fixing unevenness, and the vibration energy is converted into heat by applying pressure. By introducing the concept of ultrasonic welding, it is possible to obtain a thermal press effect without requiring a large heat source unlike the conventional heat roll fixing method.

[Brief explanation of drawings]

Figure 1 is an electrophotographic copying machine, Figures 2 and 3 are explanatory diagrams of a conventional fixing section, Figure 4 is a configuration diagram of an embodiment of the present invention,
Figure 5 is a block diagram of another embodiment of the present invention. l...Photoconductor drum 2...Charging electrode 3...Document stand 4...Document cup (-5...Illumination lamp 6.
...Mirror 7...Lens 8...Mirror 9...Toner box IO...Developing sleeve 11
...Transfer machine 12...Paper feed roller 13...Transfer electrode 14...Separation electrode 15...Transfer paper transport section
16... Fixing section 17... Discharge section 18... Cleaner section 19... Motor 20... Transfer paper 21... Fixing roller 22... Roller 23... Ultrasonic vibrating section 24°・°oscillator 30...Fixing roller
31...Ultrasonic transmitter 32...Ultrasonic oscillator 33
... Oscillator Tokken Applicant TDC Co., Ltd. Agent Patent Attorney Akira Yamatani

Claims (1)

[Scope of Claims] 1. In a toner fixing device that fixes the toner image by a roller to the transfer paper onto which the toner image has been transferred, 9. A toner fixing device characterized in that at least one of the rollers is ultrasonically vibrated by an ultrasonic vibration means, and a toner image is fixed based on the ultrasonic vibration. 2. The toner fixing device according to claim 1, characterized in that an ultrasonic transmitter is disposed inside the roller. A toner fixing device according to claim 1, characterized in that an ultrasonic transmitter having a radius of seven wavelengths is arranged.