JPH1020590A - Paper feeding speed controller for electrophotographic system printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry consecutive paper sheets having perforations, without deviating them, as well by controlling the timing of perforation signals, so as to make it at constant intervals, on the basis of signals generated at fixed periods, in accordance with the pitches of the perforations. SOLUTION: A 1/2 inch signal generating circuit 21 or a signal circuit 22 for a sensor 1 is selected by a selector 24, with a paper selecting signal for choosing a paper having the perforations or a paper not having the perforations. The speed of the paper is calculated by a speed calculating circuit 25, based on the selecting signal and the signal from a signal circuit 23 for a sensor 2. Further, the speed of a carrying roller 53 is corrected with the signal from a speed correcting circuit 26. In other words, when the pitches of the perforations are at intervals of every 1/2 in., the timing of the perforation signals is controlled to be at the constant intervals, on the basis of 1/2 inch signals generated in the fixed periods, in accordance with the pitches of the perforations, not to deviate them, so that carrying without deviation of perforation is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed speed control device for an electrophotographic printing apparatus, and more particularly, to a paper feed speed control device for continuous paper.

[0002]

2. Description of the Related Art FIG. 4 shows an operation flow for conveying a sheet having a perforated hole formed by a conventional technique in an electrophotographic printing apparatus. FIG. 5 shows a circuit configuration of a paper feed speed control device according to the related art.

Conventionally, a mark printed by an image recording unit is sequentially detected by a sensor 1 signal circuit 22 and a sensor 2 signal circuit 23, a speed calculation circuit 25 calculates a paper speed, and a signal from a speed correction circuit 26 is used. The speed of the paper transport roll 53 has been corrected.

When a paper having a perforated hole is conveyed by the paper feed speed control device, the perforated hole of the paper is sequentially detected by the sensor 1 signal circuit 22 and the sensor 2 signal circuit 23 instead of the print mark, and the paper is fed. The feed speed can be corrected.

[0005]

However, due to variations in the detection time of the sensor 1 signal circuit 22 and the sensor 2 signal circuit 23, the actual paper feed speed is deviated from the hole of the paper. That is, since the perforated paper is perforated in the width direction, when the perforated paper is transported by the paper feed speed control device, the perforations are shifted.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a paper feed speed control device capable of conveying continuous paper having a perforated hole so that perforations are not displaced in an electrophotographic printing apparatus for conveying and printing continuous paper having no perforated hole. To provide.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic printing apparatus for transporting and printing continuous paper having no perforations, and for transporting and printing continuous paper having perforations using the printing apparatus. In the case of paper with perforated holes, in order to prevent the perforated holes from shifting, the timing of the perforated hole signal is set for a certain period of time based on a signal that is generated at a constant period that does not vary according to the pitch of the perforated holes. It is achieved by controlling so that

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 is a flow chart showing the operation when a sheet having a perforated hole according to the present embodiment is transported. FIG. 2 is a block circuit diagram of the paper feed speed control device in the present embodiment. FIG. 3 is a conceptual diagram of an electrophotographic printing apparatus.

The overall configuration of the electrophotographic printing apparatus will be described with reference to FIG.

A recording section for forming a toner image includes a charger 102 for charging the outer periphery of the photosensitive drum 104, a laser emitting section 101 for forming an electrostatic latent image on the photosensitive drum 104, and a toner image on the electrostatic latent image section. Developing unit 103 to be formed, transfer device 106 for transferring a toner image to paper, and photosensitive drum 10
4 is provided with a cleaner 105 for removing residual toner after transfer.

A paper transport unit for transporting continuous paper supplied from a paper feed unit (not shown) includes an auxiliary roller 51, a guide 52, and a roller 5 for transporting paper in order from the paper supply side.
3, 54; a feed roller 56 for transporting the transferred paper; driven rollers 55 provided at both ends of the paper so as not to contact a transferred image on the paper; a buffer 5 for applying a constant tension to the paper
7. A fixing unit including a pre-heater 58, a heat roll 59, and a backup roll 60 for fixing a transferred image on a sheet is provided. An auxiliary roller 61 for guiding the sheet to the outside is provided downstream of the fixing unit.

Here, the speed correction of a sheet having no feed hole will be described.

When a sheet without a perforation is conveyed, a mark is printed at regular intervals outside the printing area of the sheet in the image recording section, and this print mark is printed on the sensor 1 mounted in the sheet conveying direction. And 2. Sensors 1 and 2
Is the distance a and the process speed of the printing apparatus is b, the time t from when the print mark is detected by the sensor 1 to when the print mark is detected by the sensor 2 can be obtained by an equation shown by t = a / b.

Therefore, the time from when the print mark is detected by the sensor 1 to when the print mark is detected by the sensor 2 is t.
By correcting the speed of the transport roll 53 so as to satisfy the following condition, the paper speed can be adjusted to the process speed of the printing apparatus. It should be noted that the accuracy of the paper feed speed can be improved by reducing the interval between the print marks.

Next, speed correction of a sheet having a perforated hole will be described.

Assuming that the pitch of the perforations is every 1/2 inch, in order to prevent the perforations from being displaced, a 1/2 inch signal generated at a constant period without variation in accordance with the pitch of the perforations. By controlling the timing of the perforated hole signal to be a fixed time based on the reference, the speed of the paper can be adjusted to the process speed of the printing apparatus, and the paper can be transported so that the perforated hole does not shift. it can. In this embodiment, the speed of the paper transport roll 53 is corrected so that the time from the timing of the generation of the 1/2 inch signal to the detection of the feed hole by the sensor 2 becomes t.

The circuit configuration of the paper feed speed control device according to this embodiment will be described with reference to FIG.

A 1/2 inch signal generating circuit 21 or a sensor 1 signal circuit 22 is selected by a selector 24 according to a paper select signal for selecting paper having a perforated hole or paper having no perforated hole.
The speed calculation circuit 25 calculates the speed of the sheet based on this signal and the signal from the sensor 2 signal circuit 23. Further, the speed of the paper transport roll 53 is corrected by a signal from the speed correction circuit.

[0020]

According to the present invention, in an electrophotographic printing apparatus for conveying and printing continuous paper without a perforated hole, a paper feed speed control capable of conveying a continuous paper with a perforated hole without shifting the perforation. An apparatus can be provided.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating an operation of conveying a sheet on which a perforated hole has been formed according to an embodiment.

FIG. 2 is a block circuit diagram of a paper feed speed control device according to the present embodiment.

FIG. 3 is a conceptual diagram of an electrophotographic printing apparatus.

FIG. 4 is a flowchart showing an operation when conveying a sheet on which a perforated hole has been formed by a conventional technique.

FIG. 5 is a block circuit diagram of a paper feed speed control device according to the related art.

[Explanation of symbols]

1, 2, ... sensor, 21 ... 1/2 inch signal generator, 2
2 ... Sensor 1 signal circuit, 23 ... Sensor 2 signal circuit, 24
... Selector, 25 ... Speed calculation circuit, 26 ... Speed correction circuit, 27 ... Paper select signal, 51 ... Auxiliary roller, 52
... Guide, 53, 54 ... Convey roller, 55 ... Driving roller, 56 ... Feed roller, 57 ... Buffer, 58 ... Preheater, 59 ... Heat roll, 60 ... Backup roll, 61 ... Auxiliary roller, 101 ... Optical unit, 102
... Charging device, 103 developing unit, 104 photosensitive drum, 105 cleaner, 106 transfer device.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Yoji Hirose 1060 Takeda, Hitachinaka-shi, Ibaraki Prefecture Inside Hitachi Koki Co., Ltd.

Claims (2)

[Claims] 1. A sheet feeding unit for frictionally conveying a continuous sheet, an image recording unit for recording an image on the sheet, a sheet feeding speed correcting unit, and a sheet feeding speed based on detection outputs of at least two sensors provided in the sheet feeding direction. And a speed correction drive control unit for inputting a speed correction value of the calculation unit and driving the paper feed speed correction unit, and for conveying and printing continuous paper without feed holes. In the photographic printing apparatus, when conveying and printing continuous paper having a perforated hole using the printing apparatus, the timing of the perforated hole signal is adjusted based on a signal generated at a constant cycle in accordance with the pitch of the perforated hole. An electrophotographic printing apparatus characterized in that it is controlled for a fixed time. 2. A paper feed speed control apparatus according to claim 1, further comprising means for selecting whether the paper has a feed hole or a paper without a feed hole. apparatus.