JPS61200568A - Flash fixing device for recording device - Google Patents

Abstract

PURPOSE:To obtain optimum fixation performance regardless of toner in use by controlling the quantity of flash light emission of a fixing device according to the material of the toner in use. CONSTITUTION:A microcomputer 101 triggers SCRs 1 and 2 at the same time after the time from when a recording paper detection sensor placed in front of a fixing device turns to when the front end of recording paper reaches the exit of a fixation area A, and a discharging current flows to a xenon lamp Xe, which illuminates. Then, a thyristor SCR 3 is turned on after T1 seconds determined by a microswitch MS-1 according to the color of the toner to stop the illumination. The quantity of flash light emission is controlled by setting the time T1. Then, flash light is emitted to a next recording paper part through the same operation to fix the recording paper. The number of times of repetitive light emission is determined by the microcomputer on the basis of the recording paper size and range. Thus, optimum fixation performance is obtained regardless of the toner in use.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fixing device for a recording device such as a copying machine, facsimile machine, or printer, and more particularly to a flash fixing device that fixes an unfixed toner image by applying flash energy.

(Prior Art) A flash fixing device with a short waiting time, no need to heat the recording material, and a simple configuration is conventionally known as having a configuration as shown in FIG. The recording paper is conveyed in the direction of the arrow, and each time a new portion of the recording paper passes through area A facing the xenon tube 30, the xenon tube emits light and fixes the toner image. do.

On the other hand, due to the demand for colored toner images, more and more toner images exhibit a variety of colors.1 Various containing materials are used for pigments and magnetization, and the particle size and energy absorption rate of the toner image (
The spectral absorption rate for a given wavelength of light also changes.

When fixing these toner images with a conventional flash fixing device, if a large light emitting lamp is used, the toner images can be fixed without any problem.

However, in a device that uses toner whose glass transformation point (sometimes simply referred to as melting point) is 100°C or lower and requires a smaller device by lowering the output of the light emitting lamp, the above problem occurs. There was a problem in that various types of flash fixing properties varied greatly depending on the material of the toner image.

(Object of the present invention) The object of the present invention is to provide a solution to the above-mentioned problems, to stabilize the fixing performance, and to stabilize the fixing of toner images using low melting point toner regardless of the material. Moreover, the present invention aims to provide a flash constant M device which can also be made compact.

Another object of the present invention is to provide a flash fixing device that can be easily controlled depending on the toner material.

(Summary of the Present Invention) In order to achieve the above object, the present invention provides a means for variably controlling the amount of flash energy (application time, number of times of application) applied to an unfixed toner image, depending on the material on which the unfixed toner image is formed. It is characterized by having the following.

In particular, the present invention uses a toner constituting a toner image having a glass transformation point of 100° C. or lower, preferably 75° C. or lower,
The above-mentioned material is particularly effective in a recording device in which parameters include differences in color due to dyes, etc., toner magnetism, and especially differences in toner particle size.

According to the present invention, even when various toners are used, the fixing effect of the flash fixing device can be stabilized and made more reliable.

(Description of Embodiments) First, FIG. 1 shows an overall configuration in which the present invention is applied to a small electrophotographic copying machine. Reference numeral 1 denotes a document mounting table made of a transparent member, which moves reciprocally in the direction of the arrow. Reference numeral 2 denotes a condensing light transmitting member which exposes the photosensitive drum 3 with a light image of the document image on the document table 1 through a slit.

The photosensitive drum 3 rotates in the direction of the arrow. 4 is a corona charger that uniformly charges the photosensitive drum; 5 is a developer that charges the uniformly charged photosensitive drum with a focusing light transmitter 2;
The electrostatic latent image formed by light image exposure is heated to a glass melting point of 70.
Images are visualized using various toners of various colors and materials at temperatures around ℃.

On the other hand, the paper P is fed onto the drum surface by a paper feed roller 6 and a registration roller 7, and the image on the drum is transferred by a transfer body charger 8. Thereafter, the paper is separated from the drum by the paper separation means 13, passed through the guide 9, and then transferred to the fixing device 10.
sent to. The toner image on the paper P is flash-fixed by the fixing device 10, and then the paper P is discharged onto the tray 12 by the paper discharge roller 11. The toner remaining on the photosensitive drum 3 is removed and collected by the cleaning means 14.

FIG. 1 shows a control example of the configuration shown in FIG. 2 of the present invention, where T1 is 2
A step-up transformer whose next side is 350V, Dl is a rectifier, C1 is a charging capacitor, Xe is a xenon lamp used for flash emission, T2 is a transformer for energizing the xenon lamp, and 5CRI is energizing the xenon lamp. Thyristor, 5CR2, which inputs the gate signal for
5CR3 is a thyristor that turns on and off the discharge current path of the xenon lamp, and 5CR3 is a thyristor that inputs a gate signal to stop the discharge of the xenon lamp.

C2 is a capacitor required to turn off the thyristor 5CR2, 101 is an 8-bit microcomputer that controls the above-mentioned flash emission -1DRI-DR3 connects the output signal of the microcomputer to the thyristors 5CR1-3CR, respectively.
A driver that allows you to trigger with 3, MS 1
, MS2.

MS3 is a sensor that corresponds to a protrusion that indicates, in order, the type of color added to the developing device or cartridge, the toner particle size, and the degree of magnetism.

The flash light emitting section basically uses the flash light emitting circuit used in conventional cameras.

However, the amount of light emitted is controlled by a microcomputer based on the amount that corresponds to the toner material used.

First, when the power is turned on, the charging capacitor CI is charged. The charging voltage is divided by resistors R1 and R2 and monitored by the A/D of the microcomputer. When the recording paper bearing the transferred toner image enters the flash fixing device due to the copying operation, the microcomputer simultaneously triggers the thyristors 5CRI and 5CR2, as shown in FIG. A high voltage is generated on the secondary side of the transformer T2 by the trigger of the thyristor 5CRI, and the xenon lamp is triggered to start discharging and emit light. At the same time, the thyristor 5CR2 is triggered, so a discharge current flows. Then, after a certain predetermined time T, the thyristor 5CR3 is triggered. When the thyristor 5CR3 is triggered, the charge in the capacitor C2 that has been charged through the resistor R7 is discharged through the thyristor 5CR3, so that 5CR2 is reverse biased and turned off. Thereby, flash emission is stopped. Since the amount of flash light emitted is as shown in Figure 5 with respect to time,
The amount of light emitted can be controlled by setting 1 ri per hour.

Then, 12 seconds later, the same operation is performed again to emit a flash on the next recording paper section to fix it. The flash interval time T2 is determined by the copying operation speed (the conveying speed of the recording paper) and the range A fixed by one flash emission.

The number of light emission repetitions N is determined by the microcomputer according to the recording paper size and range A. For example, A4 (210
When using recording paper (298 mm x 298 mm) and feeding vertically, the copying speed is 60 m layers/sec.

If the range A is 30 mm, the recording paper passes through the fixing device in 5 seconds, and a flash is emitted 10 times every 0.5 seconds during that time.

FIG. 6 shows an example of a control flowchart of this fixing device.
First, in the pre-copying process.

The developing device determines whether the toner used in this copy is a color toner other than black leather or black toner.

Check whether there is a protrusion SL provided on the cartridge shown in the TS8 diagram in which the drum and cleaner are integrated.

Verify by microswitch MSI. The protrusions S2 and S3 indicated by broken lines in FIG. 8 have the aforementioned toner particle diameters,
Although this indicates a magnetic layer, this embodiment will be explained as an example in which this is excluded.

If the cartridge is a color toner, MSl=1, if it is a black toner, MSl=O, and as shown in the flow on the left side, for color toner, N1 is set for the light emitting time T, and for black toner, N1 is set. is set to N2 (N2 <Nl). Flows (1) to (2) relate to flash control in the fixing device. When the recording paper detection sensor placed in front of the fixing unit turns on and 5EN=1, the time N from which the leading edge of the recording paper reaches the exit of fixing area A
After o (seconds), the first flash is emitted. Then, T determined in advance according to the toner color
, seconds later, the thyristor (SCR3) is turned on to stop emitting light. Then, 12 seconds after the start of strobe light emission (0.5 seconds in the above example), the number of flashes C is subtracted by 1, and it is checked whether the remaining number of flashes is zero. If it is not zero, the same conditions are repeated.

For example, the number of times the flash is repeatedly emitted C is 10 times in the case of A4 paper, and is set depending on the size of the recording paper.

If the paper is not fed from a cassette and the size of the recording paper is unknown, the maximum recording paper size of the copying machine is set.

If the control is performed so that the larger the toner particle size is, the longer the light emitting time increases, and the larger the toner magnetic layer is, the longer the light emitting time is, the same control as above will be obtained, and these relative differences will be It is sufficient to perform a predetermined control flow after detection by S2, S3, etc.

As explained above, by changing the amount of flash light emission depending on the material of the toner used, it has become possible to obtain optimal fixing performance no matter what kind of toner is used.

Next, a similar effect can be obtained by controlling the number of times the flash is emitted. In the previous example, within the fixing area A, light was emitted only once in the recording paper area.

However, the fixability of the color toner can also be improved by emitting light twice or more in the same area of the recording paper to increase the total irradiation amount.

As an example of the implementation configuration, FIG. 3 can be used as is.
Then, the software changes the light emission interval T2 depending on the color, as shown in FIG. 7, assuming that the flash light emission time TI is constant. That is, in the case of black toner, N'2 is set as T2 (0.5 seconds in the previous embodiment), and in the case of color toner other than black, N'+ (for example, 0.25 seconds) is set as T2.
seconds) is set. The flow during fixing is the same as shown in Figure 6 ■ to ■. If No. is a color toner, if it is irradiated twice, the first light emission will start when the top of the recording paper is exactly in the middle of area A. is set to

Also, the number of times the light is emitted is set to double. In the case of black toner, it is fixed by emitting light once in the - area, as in the above embodiment. In this way, similar effects can be obtained by increasing the number of times the flash is emitted in the case of color toner, which is not much different from the previous embodiment.

Now, the number of times the flash is emitted is varied while keeping the flash emission time T1 constant, but of course it is also possible to add more fine control by changing 3r.

Throughout the examples, black toner and color toner have been explained as examples, but even if the toner information added to the cartridge is magnetic toner, non-magnetic toner, or particle size, the irradiation amount can be controlled accordingly in this implementation as well. The present invention, which can be carried out by way of example, is applicable to all recording apparatus transports.

Conventionally, the capacitors and the like for flash emission were large, and the light emission control section was large-scale.

In this embodiment, toner images can be formed using toners with low melting points (e.g., 70°C) due to improved toner materials, and the amount of flash light emitted is small. Variations can also be prevented.

Furthermore, the flash fixing device of the present invention can be used in small and lightweight copying machines and facsimile fixing devices to a great extent.

(Effects of the Invention) Since the present invention controls flash energy according to the material of the toner forming the toner image, the fixing performance can be stabilized even if various toners change.

In particular, the present invention is extremely effective in recording devices that use low-melting-point toner and are intended to be miniaturized.

[Brief explanation of the drawing]

Fig. 1 is a control circuit diagram of an embodiment of the present invention, Fig. wS2 is a schematic configuration diagram of a copying machine to which the present invention is applied, Fig. 3 is an explanatory diagram of conventional flash fixing, and Fig. 4 is a timing diagram of an embodiment of the present invention. 5 is a graph showing changes in light emission amount with respect to flash time, FIGS. 6 and 7 are flowcharts of main parts of the embodiment of the present invention, and FIG. 8 is a graph showing the cartridge 14 shown in FIG. 2.
FIG. Xe is a flash lamp, CI + c21 c3 is a capacitor, 14 is a cartridge, IO is a fixing device, s,
l s21 s3 is disaster, MSI, MS2゜MS3 is micro switch. Fig. 7 No. 8 Haze

Claims (3)

[Claims] (1) In a flash fixing device having means for emitting flash energy in order to fix an unfixed toner image on a recording material, depending on the material on which the unfixed toner image is formed, the amount of energy applied to the fixing of the unfixed toner image is applied. A flash fixing device comprising means for controlling the amount of flash energy. (2) The flash according to claim 1, wherein the material is an additive contained in a thermoplastic material, and the control means controls the duration of application of flash energy or the number of times of application of flash energy. Fusing device. (3) The flash fixing device according to claim 1 or 2, wherein the toner image has a glass transformation point of 100° C. or lower.