JPS62255343A - Paper meandering preventive device - Google Patents

Abstract

PURPOSE:To secure stable paper travelability, by altering a control angle of a buffer arm and its tension according to a type of paper. CONSTITUTION:Simultaneously with paper running, pressure is produced in a buffer arm, whereby a position detecting plate 7 operates as well. If so, a sensor substrate 8 detects a position of the buffer arm 2 by means of the slit bored in this position detecting plate 7, and performs revolving speed control over a heat roll so as to cause it to become a target angle. An adjusting dial at the front side is rotated round to 'strong' or 'weak' whereby a sensor substrate 9 is rotated, while a target angle of the buffer arm 2 is altered and also its tension is altered and simultaneously a compressive pin 22 serving as a stopper for a coil spring 13 is rotated, varying the tension. With this constitution, multifarious rolls of paper are stably travelable.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a paper traveling mechanism such as an electrophotographic printer for outputting continuous paper, and particularly to a paper meandering prevention mechanism thereof.

[Conventional technology]

Conventionally, in this type of electrophotographic printer for outputting continuous paper, there has been an electrophotographic printer for outputting continuous paper having a thermocompression roll type fixing device, a cross-sectional view of which is shown in FIG. 2, for example. That is, continuous paper 1 with a visible image carried by a tin rocket of a tractor passes through a buffer arm 2 held by a buffer arm shaft 6 and a spring 5 at the entrance of the fixing section, and enters a heat roll 3 and a pressure roll 4. A permanent image was obtained by fusing the toner to the paper using heat and pressure. At this time, tension was applied to the continuous paper 1 of the back 7 arm 2 Fi, and the same position was maintained as long as there was no change in the tractor speed and the rotation speed of the heat roll 3 and pressure roll 4. Therefore, the position of the buffer arm 2 is detected by the position detection plate 7 disposed on the frame 27 via the sensor board 8 as shown in FIG.
By controlling the rotation speed of the paper, stable paper running performance was obtained.

[Problems to be solved]

In printers equipped with the conventional buffer arm mentioned above, paper cannot be printed unless all factors, such as the parallelism and levelness between the tractor and the heat roll, and the pressure difference between the left and right sides of the heat roll and pressure roll, are set within certain conditions. The disadvantage is that the paper loses its stability and begins to meander to the left or right, causing the paper to get caught between the heat roll and the pressure roll, resulting in wrinkles. For this reason, in the past, stable running of paper has been ensured by bringing the above-mentioned factor conditions as close to ideal values as possible. Therefore, the tension and control angle of the buffer arm have been changed by considering the type or unit (1st thickness of paper) of each type of paper, and the above-mentioned factor conditions have been given a considerable range to accommodate various types of paper. However, it was still not possible to obtain a common tension and control angle across all types of paper.

[Means for solving problems]

In order to solve the above-mentioned conventional problems, the present invention provides a paper meandering prevention mechanism that can change the control angle and tension of the buffer arm for each type of paper on the paper travel path between the image forming transfer section and the fixing section. It is an object of the present invention to provide a paper meandering prevention mechanism that ensures stability in paper running.

In other words, the present invention widens the control angle of the buffer arm to weaken the tension when handling thin paper and narrow width paper, and narrows the control angle of the buffer arm to increase the tension when handling thick paper and wide width paper. The present invention aims to provide a mechanism for preventing paper meandering.

To this end, the present invention provides an electrophotographic printer for outputting continuous paper, which includes a panfer arm mechanism that is located on the paper travel path between the IfI image forming transfer section and the fixing section and applies tension to the paper. The present invention provides a paper meandering prevention mechanism characterized in that the stability of the paper is guaranteed by changing the control angle and tension of the arm depending on the type of paper.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows in detail one embodiment of the paper meandering prevention mechanism of the present invention, in which (a) is a top view, (b) is a front view, and (C) is a partial side view. A top view of the gear train, (e) shows a plan view along line AA'.

The buffer arm 2 attached to the buffer arm shaft 6 is under tension by two coil springs 13 and 14 on the front and rear sides of the device. A position detection grate 7 is directly screwed to the tip of the buffer arm shaft 6, and a sensor board 8 is attached to sandwich the position detection plate 7. Pressure is generated in the buffer arm 2 at the same time as the paper travels, and the position 1141 output plate 7 also operates. Then, the sensor board 8 detects the position of the buffer arm 2 through the slit made in the position detection plate 7VC, and controls the rotation speed of the heat roll 30 so that the desired angle is achieved. An adjustment dial 18 which is fixed together with 23 and fixed to the other sleeve 17. It is a mechanism that can rotate around the buffer arm shaft 6 using the guide 10 as an axis, which is connected to the drive gear 16.

The sensor board 8ti is provided with a tooth profile and is variable in 10 steps by a detent pole 11 which is pushed by a spring 26 around the shaft, and is locked at each position tltVc.

On the other hand, with the rotation of the adjustment dial 18 and the drive gear 16, the spring compression gear 2o fixed to the sleeve 21 via the inverter gear 19 rotates in a direction opposite to the direction of the base plate 9. Further, a compression pin 22 is fixed to the spring compression gear 20, and this compresses and tensions the coil spring 13rj with the same tension as the buffer arm 2.

The movement of the gear and coil spring 13 in the case of compression is shown in Figure 1 (d
) (It becomes like e+.

As described above, by turning the front side 14 adjustment dial to strong or weak, the sensor board base 9 is rotated, the objective angle of the buffer arm 2 is changed, and the tension is changed. At the same time, the compression bottle serving as a stopper for the coil spring 13 is rotated. 2
Rotate 2 to change the tension. This makes it possible to provide a paper meandering prevention mechanism that allows a wide variety of continuous papers 1 to run stably.

Note that the rear side coil spring 14f'i is fixed. c) The collar 15 allows the tension to change only in accordance with the rotation of the sensor board base 9.

In addition to the above-mentioned method, a method of winding and unwinding one end of the spring 5 in FIG. 2 manually or by a motor or the like may be adopted as a method of changing the tension '5 of the puffer arm 2 ( (not shown).

〔Effect of the invention〕

As explained above, the present invention provides a meandering prevention mechanism that can change the buffer arm control angle and tension on the paper traveling path between the image forming transfer section and the fixing section, thereby stably handling paper of multi-ta. Since running is guaranteed, it has the effect of providing a stable electrophotographic printer.

That is, the present invention has the effect of being able to provide a stable electrophotographic printer that can ensure stable paper running properties, including prevention of scratches and tears in the feeding holes, with many types of paper.

[Brief explanation of drawings]

Figure 1 (a3 is a top view showing an embodiment of the present invention, Figure 1 mountain) is a front view, Figure 1 (C) is a partial side view, Figure 1 (d)
is a top view of the gear train showing the movement of the gears in the case of compression, the first
Figure (e) shows the movement of the coil spring in the case of compression A A
2 is a sectional view of a conventional fixing device, and FIG. 3 is a side view of a conventional fixing device. 1... Continuous paper 2... Buffer arm 3... Heat roll 4... Pressure fi o -
5... Spring 6... Buffer arm shaft 7... Position detection plate 8... Sensor board 9... Sensor board base 10...
Guide 11...Detent ball 12...Spring 1
3...Coil spring 14...Coil spring 15
...Stopper 16...Drive gear 17.
・Sleeve 18 ・Adjustment dial 19 ・
...Reverser gear 20...Spring compression gear 21...Sleeve 22...Compression bin 23...Sensor rotating gear 24...Post 2
6...Spring 27...Frame 28...Frame agent Patent attorney Mura 1) Yudai Miki 1rA (d) (e)

Claims (1)

[Claims] An electrophotographic printer for outputting continuous paper, etc. has a buffer arm mechanism that is located on the paper travel path between the image forming transfer section and the fixing section and applies tension to the paper, and controls the control angle and tension of the buffer arm to control the tension of the paper. A paper meandering prevention mechanism that ensures stable running of the paper by changing it according to the type of paper.