JPS60121478A - Recording device - Google Patents

Abstract

PURPOSE:To fix an image completely to a recording paper where fixing is unsatisfactory or fixing is difficult, by providing a refixing means which allows a recording material passing a fixing means to pass the fixing means again. CONSTITUTION:The toner image transferred onto a transfer paper P is fixed normally by a pair of fixing rolls 10a and 10b, and the transfer paper P is ejected by an ejecting roll 11. If fixing is judged to be incomplete, a refixing designating button 25 is operated or a driving control circuit 24 is operated by a detection signal of a paper quality detecting means 26, and rolls 10a and 10b and a guide roll 27 are driven in the - direction, and a paper feed switching means 28 is operated downward. Then, the transfer paper P is not ejected but is sent to rolls 10a and 10b again and the image is fixed again. Next, rolls 10a and 10b are driven in the + direction, and the transfer paper P after refixing is sent to an ejected paper tray 12 by the restored means 28. Thus, the image is fixed completely onto the recording paper where fixing is unsatisfactory or difficult.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for refeeding a recording material to the fixing mechanism of the recording device and re-feeding the recording material to the fixing mechanism of the recording device when the fixing processing of the recording material is incomplete in a recording device such as a copying machine. The present invention relates to a recording device capable of fixing images.

For example, in conventional heat fixing mechanisms in recording devices such as copying machines, printers, facsimile machines, printing machines, etc., the fixing performance depends on all types of recording materials used (for example (1) resin sheets, thick letters such as postcards, thin letters, etc.) However, it has not been possible to perform satisfactory recording on all types of recording materials (hereinafter referred to as transfer paper). This is due to energy saving, restrictions on power usage, etc. Therefore, in order to improve the above-mentioned fixing performance, (1) the fixing temperature immediately after Wait up is set high.

@ Set the temperature higher when the temperature is low.

Change the process speed depending on the thickness of the transfer paper.

■ Before the transfer paper reaches the fixing device, take care to preheat the upper and lower rollers by rotating them together if the rollers are fixed.
It is usually attempted to compensate for this with the minimum necessary power, and in special cases by additional means to compensate for its performance in the course of the copying process.

However, although adding these compensation measures improves performance, it complicates temperature control, increases costs, and reduces reliability. This method has disadvantages such as not being suitable for high-mix, low-volume, high-flexibility recording VC, such as when copying plain thick paper or copying with high toner density.

The present invention eliminates the above-mentioned drawbacks and at the same time is highly reliable,
Moreover, it is an object of the present invention to provide a recording apparatus that can obtain stable fixing properties that are independent of the lifespan of parts other than the fixing section.

The present invention will be explained in detail below based on embodiments shown in the drawings.

First, the structure of the recording apparatus will be explained. In FIG. 1, reference numeral 1 denotes a document mounting table made of a transparent member, which reciprocates in the direction of arrow a. Reference numeral 2 denotes an imaging element play which slit-exposes the optical image of the document image on the document table 1 onto the OPC photosensitive drum 3. Note that the photosensitive drum 3 rotates in the direction of the arrow. 4
It is necessary to use a corona charger to apply a uniform charge to the photosensitive drum 3. A developing device 5 develops an electrostatic latent image formed by exposing the uniformly charged photosensitive drum 3 to light using the array 2 with toner.

On the other hand, the transfer sheet (P) is fed onto the 3 surfaces of the citrate by the feeding roller 6 and the register row 27, and the toner image on the citrate is transferred by the transfer charger 8. Thereafter, the sheet is separated from the drum by the separating means 13), passes over the guide 9, and is sent to the fixing roller pair 10 by the roller 9a located at the end of the conveyance path. The toner image on the sheet is fixed by a pair of fixing rollers 10, and the sheet is discharged onto a sheet tray 12 by a discharge roller 11. At this time, fixing roller 1
The remaining toner offset to 0a is cleaned by a cleaning rose (10c) serving as a cleaning member. Note that this bat 10c is made of a material such as felt.

On the other hand, the toner remaining on the photosensitive drum 3 without being transferred is
(by the cleaning device 14). Furthermore, 15 is an illumination system for exposing the original, and 16 is a filter such as a heat ray absorption filter.

In this embodiment, the drive system and electrical system are roughly divided into two systems9, and only the paper conveyance and fixing functions can be operated.

That is, the feed roller 6, register roller 7, conveyance roller 9a, paper ejection roller 11, and pressure roller 10b, which are related to paper conveyance, are operated by a motor (not shown) connected to the fixing roller 10a via a gear. It is driven by shear gears, belts, and frictional followers. This is the driving of parts related to the image forming process, such as the original placing table 1, the developing unit 5, and the cleaning unit 14, which are driven by a motor (not shown) connected to the photosensitive drum 3 via gears, belts, etc. This means that it is a different system. Furthermore, it is preferable that the above-mentioned two systems of drive mechanisms are normally driven in synchronization during copying, and in this embodiment, the respective motors of both drive mechanisms are connected to the DCC hull top motor, which is easy to synchronize in timing and speed. are using.

Further, it is not necessary to provide two independent motor systems; it is also possible to separate only the drive systems as described above and systematically separate the drives using clutches. This system can be said to be a more preferable drive system since it is easier to synchronize when operating two systems simultaneously (5). 20a, 20b.

21a and 21b are detection elements that detect the passage of the transfer paper P, 20a+21a is a light source, and 20b
.

21b is a light receiving element made of silicone semiconductor. 2
2.23 is a separating claw for separating the transfer paper P attached to the fixing roller 10m from the fixing roller 10a; 24;
is a drive control circuit for driving the above-mentioned transport roller 29a, fixing roller 10a, and paper ejection roller 11 in the forward or reverse direction, and this drive control circuit 24 includes a re-fixing designation button 25, a paper quality detection means 26, Or the above-mentioned sensing element 2
0b.

21b, the rollers 9a, 10a.

11fi: Drive control is possible. Note that although the paper quality detection means 26 in the above embodiment was arranged immediately after the feed roller 6, it may be arranged immediately before the conveyance roller 9a as shown by the chain line.

The above is the configuration of this embodiment.Next, its operation will be described. Normally, the transfer paper P on which the toner image has been transferred by the photosensitive drum 3 is supplied to the fixing roller (6) and the roller pair 10. , after the toner image on the transfer paper P is fixed on the transfer paper surface by the fixing device 1o, the ejection roller 1
If it is determined that the fixing of the toner image by the pair of fixing rollers 10 is incomplete, either operate the re-fixing designation button 25 or use the paper quality detection means 26 to When the paper quality detection means 26 detects that the transferred transfer paper is a thick paper such as a postcard or a resin sheet that is difficult to fix an image on.
The drive control circuit 24 operates in response to a signal from the designation button 25 or the detection means 26, and the output from the control circuit 24 causes the fixing roller 10a, pressure roller 10b, and guide roller 27 to be activated as shown in FIG. 3(A). While being driven in one direction, the paper feed switching means 28 moves downward, and the transfer paper P is pressed by the fixing roller 10 and the paper feed switching means 28 and the guide row 227 without being ejected. It is sent again to roller 1, Ob, and the fixing action is applied again.

After the transfer paper P has been re-fixed, the transfer paper P is transferred to the paper ejection tray 1 from the paper feed switching means 28 which has already been restored.
2.

In the embodiment shown in FIG. 3(a) above, in order to re-fix the transfer paper P, the once-fixed transfer paper P is transported in a loop and sent again to the fixing roller, but the present invention is not limited to this. For example, the transfer paper P may be moved back and forth as shown in FIG. 3(b). That is, the transfer paper P is moved by the output signal from the control circuit 24 to the detection elements 20a, 20b, 21a, 2.
1b'ir, the unillustrated motor that drives the fixing roller pair 10 and the conveyance system drives the ejection roller 11, the fixing roller pair 10, and the conveyance roller 9a, and the conveyance roller 9a is reversely conveyed into the apparatus. The re-fixing operation is then performed.

At this time, the driving of the corona charger 4, transfer charger 8, illumination system 15, developer 5, etc. is stopped.

When it is detected that the transfer paper P passes between the paper detection elements 20a and 20b and the fixing device is completely returned, the drive motor starts rotating in the forward direction again, and the transfer paper P passes through the paper detection elements 20a and 20b. is sent to the fixing device again and output to the paper output tray 12.
〇This means that the υ transfer paper P has passed between the fixing devices three times, and three times the heat or pressure than before is applied, ensuring that the toner image is transferred to the transfer paper. Fixed. In such an apparatus, as shown in FIG. 2, it is preferable that the fixing roller 10aK is provided with separation claws 22, 23 on both the paper discharge side and the paper entry side. Further, it is more preferable that the separation claws 22 and 23 are arranged so as not to be located on the same circumferential surface of the fixing roller 10a, so as to avoid wear of the roller 10a as much as possible.

By the way, it goes without saying that the fixing device used in the present invention is not limited to the roller fixing device, but may be other fixing devices such as a constant chamber fixing device, a hot plate fixing device, a flash fixing device, a microwave fixing device, etc. .

As described above, the present invention includes an image carrier, a means for forming a toner image on the image carrier, a means for transferring the toner image on the image carrier onto transfer paper, and a means for transferring the toner image on the transfer paper. In a recording apparatus equipped with a fixing means for fixing, the recording material that has passed through the fixing means is re-fixed by passing it through the fixing means again. When it seems that the toner image on the recording paper that has passed through the fixing means is insufficiently fixed, or when using recording paper that seems to be difficult to fix, the same recording paper should be repeatedly fed and passed through the fixing means multiple times. This allows the toner image to be more reliably fixed on the recording paper.

Therefore, according to the present invention, the quality of copying in a recording device can be significantly improved.

Furthermore, when paper that is not normally used, such as postcard paper or cardboard, is used as transfer paper and a toner image is heated and fixed on this paper, there is insufficient power to raise the paper to a temperature where the toner melts. However, according to the present invention, there is a problem that the toner image is easily fixed because it is difficult to completely dissolve the toner or the undissolved toner even gets into the fibers of the paper. This has the effect of effectively solving problems.

In addition, in order to improve fixing properties as in the present invention, heat or pressure is applied to the transfer paper from one direction more than usual, so curling of the transfer paper is expected to become a problem more than ever (10). Ru. In this case, it is preferable to provide an anti-curl guide along with the device of the present invention.

[Brief explanation of drawings]

FIG. 1 is an explanatory side view showing an embodiment of the electrophotographic apparatus according to the present invention, FIG. 2 is an enlarged view of the main parts thereof, and FIG.
B) is an explanatory diagram of the operation at the time of re-fixing. DESCRIPTION OF SYMBOLS 1... Document mounting table, 2... Imaging element array, 3...
...Photosensitive drum, 4...Corona charger, 5...Developer, 6...Feed roller, 7...Register roller, 8...Transfer charger, 9...Guide, 10・
... Fixing roller pair, 10a... Fixing roller, lOb.
...Press roller, 10c...Cleaning bat, 11...Ejection roller, 12...Tray, 14...
・Cleaning device, 15...Lighting system, 16...Filter, 20a, 21a...Light source, 20b, 2
1b... Light receiving system element, 22.23... Separation claw, 24... Drive control circuit,
25... Re-fixing designation button, 26... Paper quality detection means, 27... Guide roller, 2
8...Paper feed switching means.

Claims (1)

[Claims] An image carrier, a means for forming a toner image on the image carrier, a means for transferring the toner image on the image carrier onto a transfer paper, and a fixing means for fixing the toner image on the transfer paper. In the recording device, the recording material that has passed through the fixing means is
A recording device characterized by being provided with a re-fixing means for causing the recording device to pass through the fixing means again.