JPS6353548B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrostatic recording method and apparatus having a developing machine used in, for example, a photocopy transmitter/receiver, and particularly relates to an improvement in a method and means for moving recording paper in the developing machine part. .

There are several types of electrostatic recording apparatus structures depending on the arrangement of rollers, etc., but in the pre-cut method, the structure shown in FIG. 1 is the main one. Referring to FIG. 1, the structure and operation of the pre-cut type electrostatic recording apparatus shown here will be briefly explained.

The leading end of the recording paper 1 wound into a roll is guided in a predetermined direction by a guide roller 2, and inserted between a capstan 3 and a pinch roller 4 that presses against the capstan 3. The rotation of the capstan 3 is transmitted from a rotary drive motor 5 via a belt and a pulley. Similarly, the rotation is transmitted from the rotary drive motor 5 to rotate the pulley 9, and the back pressing roller 7 is rotated integrally via the pulley 9 and the support shaft 8. The recording paper 1 that has passed between the capstan 3 and the pinch roller 4 is pushed between the back pressure roller 7 and the recording head 11 that opposes it, and is then pushed into the cutter 1.
2, it is cut to a predetermined size. The recording paper 1 cut by the cutter 12 is inserted between another capstan 14 rotated by the rotary drive motor 5 and another pinch roller 13 in pressure contact with the capstan 14, and the recording paper 1 cut by the cutter 12 1 passes over the developing machine 15.

Toner 10 containing a magnetic material is stored in the developing machine 15 and is developed there. The developed recording paper 1 is conveyed to the recording paper conveyance belt 16 stretched over rollers 18, 19, 20, and 21 while being adsorbed by vacuum, passes through the fixing device 17, and is fixed with an arrow mark. Paper is ejected in direction 6.

To explain the developing section in more detail, in FIG. 2, the recording paper 1 transported by the capstan 14 and the pinch roller 13 is transported between the introduction guide 22 of the developing machine 15 and the rotating drum inside which a magnet is mounted. 23
Pass through a small gap between the two. Here, the electrostatic latent image formed by the recording head 11 is developed by the toner 10 magnetically attracted to the outer wall of the rotating drum 23, which rotates counterclockwise.

However, because there is a difference (a>b) between the height of the ears above the magnetic poles (a) of the magnet inserted in the rotating drum 23 and the height of the ears between the magnetic poles (b), the developed image obtained is This causes striped development unevenness depending on the magnetic pole spacing and the relative speed of the recording paper 1. Therefore, in order to eliminate this drawback, the recording paper 1 is brought sufficiently close to the outer wall of the rotating drum 23, but if the peripheral speed of the rotating drum 23 is smaller than the transport speed of the recording paper 1, the recording paper 1
The toner 10 will ride on the back surface of the front end.
Furthermore, if the transport speed of the recording paper 1 is lower than the circumferential speed of the rotary drum 23, the toner 10 will ride on the rear surface of the recording paper 1 as shown in FIG. However, if the toner 10 adheres to the back surface of the recording paper 1, it will be very unsightly and will also stain the entire apparatus, hands, etc.

The present invention eliminates the drawbacks of the conventional example,
When the front end of the recording paper approaches the rotating drum, the moving speed of the recording paper is set to less than the circumferential speed of the rotating drum.
This prevents the leading edge of the recording paper from scooping up the toner on the rotating drum, and when the trailing edge of the recording paper approaches the rotating drum, the moving speed of the recording paper is set to be higher than the circumferential speed of the rotating drum. This prevents toner from covering the trailing edge of the recording paper.

An embodiment of the present invention will be described in detail below with reference to FIGS. 3 and 4. Note that although the conventional recording paper conveyance belt 16 and the recording paper conveyance belt of the present invention are slightly different in structure, they are substantially the same and there is no difference in their functions and effects. In addition, the same parts as those in the conventional example will be described with the same reference numerals.

FIG. 3 is a front view showing the structure of an electrostatic recording apparatus according to an embodiment of the present invention, and FIG. 4 is an enlarged view of the developing unit.

Reference numeral 1 denotes a roll-shaped recording paper rotatably mounted on a support shaft. The recording paper 1 is guided by a guide roller 2 and conveyed under pressure by a capstan 3 and a pinch roller 4. The conveyed recording paper 1 is introduced between a recording head 11 and a back pressure roller 7 disposed opposite thereto, and then cut to a fixed size by a rotating cutter 12. The capstan 3 is connected to a pulse motor 5 via variable speed pulleys 24, 25 and belts 26, 27, and further connected to a pulley 9 of a back pressure roller 7. In addition, the cutter 12 is connected to another motor 28, a one-turn clutch 29, and a belt 30.
connected via.

Reference numeral 14 denotes another capstan for transporting the recording paper 1 cut to a fixed size to the developing machine 15, and is connected to the variable speed pulley 25 via a pulley 31 and a belt 32. 13 is pressed against the capstan 14 by another pinch roller.

Reference numerals 33 and 33' designate photo sensors for detecting the presence or absence of the recording paper 1, which control the driver (not shown) of the pulse motor 5 using well-known switching means. When moving, the pulse motor 5 is rotated at a low speed. That is, the photo sensors 33, 33' are used to control the moving speed of the recording paper 1 to be less than the circumferential speed of the rotating drum 23. The rotating drum 23, into which a magnet is inserted, is connected to the motor 28 via a belt 34, and is rotatably mounted in the developing device 15, so that the toner 10 is magnetically attracted thereto. Further, a guide roller 35 for guiding the recording paper 1 is provided above the rotating drum 23.

16 is a recording paper conveyance belt similar to the conventional example, supported by rollers 18, 19, 20, and 21;
One of the rollers 21 is the speed change roller 36,3
7 and belts 38, 39 to connect and drive the motor 40. 17 is a fixing device that emits flash light;
Reference numeral 41 denotes a fan for vacuum suctioning the back surface of the recording paper 1 to the conveyor belt 16.

Since the present invention is constructed as described above, when the recording paper 1 on which an electrostatic latent image is formed and cut to a fixed size is transported by the capstan 14 and the pinch roller 13, and the front end of the recording paper 1 is detected by the photo sensor 33, ,
Pulse motor 5 driving capstan 14
is controlled so that the speed is low. Therefore, recording paper 1
When the front end of the recording paper 1 reaches the rotating drum 23, the transport speed is less than the circumferential speed of the rotating drum 23, so the front end of the recording paper 1 does not scoop up the toner 10 on the rotating drum 23. Further, when the recording paper 1 passes over the photo sensor 33 and there is no recording paper 1 on the photo sensor 33, that is, when the trailing edge of the recording paper 1 reaches the rotating drum 23, the transport speed is Since the pulse motor 5 is controlled so that the circumferential speed of the rotating drum 23 is higher than the circumferential speed of the rotating drum 23, the toner 10 does not cover the trailing edge of the recording paper 1.

The developed recording paper 1 is attracted to the recording paper conveyance belt 16, is thermally fixed by the flash of light from the fixing device 17, and is discharged in the direction of the arrow 6.

Furthermore, in this embodiment, the difference between the circumferential speed of the rotating drum 23 and the transport speed of the recording paper 1 is made to appear by changing the transport speed of the recording paper 1. It goes without saying that the speed difference can be made to appear by changing the circumferential speed of 23 or by changing any speed.

As described above, in the present invention, when the recording paper is moved in contact with the outer wall of the drum on which toner is adsorbed, the moving speed of the recording paper is set to be less than the circumferential speed of the drum in the step in which the leading edge of the recording paper comes into contact with the toner. In the process where the trailing edge of the recording paper comes into contact with the toner, the moving speed of the recording paper is set to be higher than the circumferential speed of the drum to prevent toner from riding up on the back surface of the front and rear ends of the recording paper. comprising a drum on which is attracted, a driving means for rotationally driving the drum, a transporting means for transporting the recording paper, and a control means for detecting the recording paper and controlling the operating speed of the driving means or the transporting means, When the arrival of the end of the recording paper is detected and the front edge of the recording paper reaches the drum, the moving speed of the recording paper is controlled to be less than the circumferential speed of the drum, and when the trailing edge of the recording paper reaches the drum, Since the moving speed of the recording paper is controlled to be equal to or higher than the circumferential speed of the drum, toner does not get on the front or rear edge of the recording paper.

[Brief explanation of the drawing]

FIG. 1 is a main configuration diagram of a conventional electrostatic recording device, FIG. 2 is an enlarged view showing a state in which toner covers the rear end of recording paper, and FIG. 3 is a configuration diagram showing an embodiment of the present invention. , FIG. 4 is an enlarged view of the developing unit of an embodiment of the present invention. 1... Recording paper, 5... Pulse motor, 10...
Toner, 13...pinch roller, 14...capstan, 15...developing machine, 23...rotating drum,
33, 33'...Photo sensor.

Claims (1)

[Claims] 1. A rotating drum with toner adsorbed on its outer wall,
In the method of developing by contacting recording paper on which an electrostatic latent image has been formed, when the recording paper is brought into contact with the outer wall of the drum to which toner has been adsorbed, the leading edge of the recording paper comes into contact with the toner. The moving speed of the paper is set to be less than the circumferential speed of the drum, and in the process where the trailing edge of the recording paper comes into contact with the toner, the moving speed of the recording paper is set to be greater than the circumferential speed of the drum, so that the toner rides on the back surface of the front and rear ends of the recording paper. An electrostatic recording method characterized by preventing. 2 A rotating drum with toner adsorbed on its outer wall.
An apparatus for developing recording paper on which an electrostatic latent image is formed by contacting the recording paper includes a drum on which toner is adsorbed, a driving means for rotationally driving the drum, a transport means for transporting the recording paper, and a recording paper. The control means controls the operating speed of the drive means or the transport means by detecting the arrival of the end of the recording paper, and when the leading edge of the recording paper reaches the drum, the recording paper is The moving speed of the recording paper is controlled to be less than or equal to the circumferential speed of the drum, and when the trailing edge of the recording paper reaches the drum, the moving speed of the recording paper is controlled to be greater than or equal to the circumferential speed of the drum. Recording device.