JPS6330272A - Optical serial printer - Google Patents

Abstract

PURPOSE:To realize a highly reliable low cost optical serial printer, by a method wherein a shield means, which is arranged along the moving direction of a printing head and prevents charging on the surface except the contact surface with a latent image forming means of a material to be recorded with the movement of the printing head, is made synchronous to the movement of the printing head. CONSTITUTION:When an image is transferred, the charge passing through an opening part 26 is applied to the paper 15 to be recorded which are superposed on a photosensitive drum 1 and an electric field for attracting the toner being the image formed on the photosensitive drum 1 to the paper 15 to be recorded is formed to transfer the toner to the paper 15 to be recorded. A moving frame 27 moves with the movement of a printing head 10 containing the photosensitive drum 1 but, since said moving frame 27 is removed from and barely contacts the back surface of the paper 15 to be recorded, the charge applied to the paper 15 to be recorded gradually flows to earth by the moving frame 27 electrically connected to the earth and a shield belt 28 and destaticized while charge is left in a degree not scattering the toner adhered to the paper 15 to be recorded before fixing the same.

Description

DETAILED DESCRIPTION OF THE INVENTION r Industrial Application Field The present invention relates to an optical serial printer, and more particularly to an optical serial printer using an electrophotographic method.

[Problems with conventional technology]

Conventionally, serial printers include type type, wire dot matrix type impact printers, and thermal, thermal transfer, and inkjet type non-impact printers, but impact printers make a lot of noise due to the impact when recording, and are difficult to install. Non-impact printers have low noise, so there are fewer environmental problems, but some methods have low recording speeds, require special recording paper, and running costs. There were also operational problems such as high Against that, 1 B).

Serial printers employing an electrophotographic process have advantages over printers using the above-mentioned methods, such as being able to record on plain paper with low noise and achieving high recording quality. This printer is described in detail in Japanese Patent Application No. 5')-215622R Electrophotographic High Speed Serial Printer and Japanese Patent Application No. 6O-12718Or Optical Serial Printer, filed by the same applicant.

In other words, in a conventional optical serial printer, for example, the first
As shown in the figure, it has a print head 10 having a cylindrical photosensitive drum 1, and a transfer charging section 13 provided opposite to the photosensitive drum 1.

Furthermore, in other conventional optical serial printers, the transfer charging section guides a movable transfer charger 21 provided with a discharge wire 2o that is equal to or larger than the width of the photosensitive drum 1, as shown in FIG. Rail 22a.

221] in synchronization with the print head 10, and the high voltage cable 23 is moved while being bent.

[Problem that the invention seeks to solve]

In a conventional electrophotographic optical serial printer, the transfer charging section 13 is open over the entire printing width, as shown in FIG.
During printing (transferring), the entire width of the recording paper 15 is charged by corona discharge, so if the printed area is only a part of the width of the paper, and if unnecessary parts are charged, the recording paper 15 will be charged by the photosensitive drum. It has been reported that since the coulonic force acts on parts other than 1, it causes the recording paper 15 to float and stick, thereby preventing normal paper feeding.

In addition, as shown in FIG. 4, other optical serial printers require a large volume to install the transfer charging section, and the high-voltage cable 23 is moved while being bent (reliability, safety, cost). The object of the present invention is to solve the above-mentioned problems and provide a highly reliable, safe, and low-cost optical serial printer.

[Means for solving problems]

The optical serial printer of the present invention includes a rotating latent image means,
A charging device that uniformly charges the surface of the latent image device, a latent image forming device that forms an electrostatic latent image according to recorded information, and a developing device that attaches a developer to the electrostatic latent image formed on the latent image device. A print head comprising a cleaning means for removing developer remaining on the latent image means and a static eliminating means for removing static electricity remaining on the latent image forming means, and a developed image is transferred to the latent image means. a conveying means for intermittently conveying the recording material; a head moving means for moving the print head in a direction intersecting the conveyance direction of the recording material; In an optical serial printer including a transfer means for transferring, the printer is arranged along the moving direction of the print head, and charges a surface other than the contact surface between the recording material and the latent image forming means as the print head moves. A shielding means for preventing the printing is provided, and the shielding means is configured to synchronize with the movement of the print head.

〔Example〕

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

FIG. 1 shows an optical serial printer which is an embodiment of the present invention. In FIG. 1, the present embodiment includes a print head 1o having a cylindrical photosensitive drum 1, a conveyance means 14 for intermittently conveying the recording material, and a print head 10 that intersects the conveyance direction of the recording material 15. Head moving means 8 for moving in the direction
a, 8Lz 9°11, and a transfer means 40 for transferring the latent image of the print head 10F onto the recording material.

The print head 10 runs along the guide rails 8a, 8b.
It is reciprocated via a drive belt 9 by a drive motor 1-1 which is a drive source. Below the print head 10, a wire discharger 40, which is a transfer means, is connected with a recording paper 15 interposed therebetween. This wire discharger 40 is connected to the print head 1o.
The discharge wire 24 is provided over the moving direction of the discharge wire 24.
．． Opening section 26, shield belt 28, and transfer charging section 1
It is composed of 3. The paper feed roller 14 feeds the recording paper 15 in a direction intersecting the direction of movement of the print head 10 . Further, in this embodiment, a charge eliminating plate 16 is provided which removes the electric charges that are not accumulated on the recording paper 15 during transfer using the wire discharger 40. In order to heat and fix the toner transferred to the recording paper 15 at the recording paper ejection section, a printer 17 is provided with a heat generating element such as a halogen lamp. and a heat roll 18 with a built-in heater 17 for storing and transmitting heat to the recording paper 15. A heat fixing mechanism is provided that includes a backup roll 19 that is provided to sandwich the recording paper 15.

FIG. 2 shows a print head of an optical serial printer. In FIG. 2, the photosensitive drum 1 of the print head 10 is a cylindrical drum coated with a photoconductive substance such as selenium, amorphous silicon, or an organic semiconductor, and as the belt 9 moves in the direction of arrow A, the carriage 7 Rotates in the clockwise direction of arrow B so that the circumferential speed is the same as the moving speed.

Regarding this rotating mechanism, please refer to Japanese Patent Application No. 127180/1986.
Optical Serial Splitter".

Furthermore, the print head includes a photosensitive drum 1 and a charging section 2 . Latent image part 3. Developing section 4. This is an electrophotographic recording mechanism section that includes a cleaning section 5 and a static eliminating section 6, and is mounted on a carriage 7. The charging unit 2 uniformly charges the surface of the photoconductive material on the photosensitive drum 1 by corona discharge.

The latent image section 3 exposes an image on the surface of the photosensitive drum 1 using ON-OFF controlled light using a laser, LED, fluorescent lamp, liquid crystal shutter, etc. to remove the charge and form an electrostatic latent image on the surface. The developing section 4 attaches toner, which is a colored resin powder having a charge of opposite polarity to the charge on the surface of the photosensitive drum 1, to a portion of the latent image outside the static eliminating device by electrostatic attraction to form a visible image. The cleaning section 5 removes residual toner on the surface of the photosensitive drum. The static eliminator 6 exposes the entire surface of the photosensitive drum 1 to remove residual charges. The carriage 7 carrying the electrophotographic recording mechanism is supported by guide rails 8a and 8b, and is reciprocated via a drive belt 9 by a spacing drive source such as a DC motor or a stepping motor.

FIG. 3 shows a wire discharger used in one embodiment of the present invention. In FIG. 3, the present wire discharger 4 includes a conductive moving frame 27 provided with an opening 26 having an area necessary for transfer.
A shield belt 28, which is a shield means made of metal woven cloth, conductive rubber, conductive plastic film, etc., is wound around the moving frame 27 in the longitudinal direction of the discharger. This wire discharger 40 has a shield belt 28 movably arranged by rollers 29, and has an internal fixed shield 25 on the inside and an external fixed shield 30 on the outside to prevent electric charge from leaking from parts other than the opening 26. Configure. Shield belt 28. And the moving frame 27 is connected to a transmission belt from a drive motor shown in FIG.
They are rotated and moved in synchronization with the movement of the print head 10 by a transmission means such as a transmission wire.

The opening 26 of the wire discharger 40 is always located below the photosensitive drum 1, which is a latent image forming means. In this embodiment, when an image is transferred, the charge passing through the opening 26 is attached to the recording paper 15 stacked on the photosensitive drum 1, and the toner that is the image formed on the photosensitive drum 1 is transferred to the recording paper 15. An electric field is formed to attract the toner to the recording paper 15, and the toner is transferred to the recording paper. Then, the print head 1 including the photosensitive drum 1
0 moves, the moving frame 27 moves, but since the moving frame 27 has an interval that may or may not touch the back side of the recording paper 15, the electric charge on the recording paper 15 is Moving frame 27 electrically connected to ground
．． Then, the toner is gradually grounded by the shield belt 28, and the toner adhering to the recording paper 15 is removed while leaving a charge to an extent that the toner does not scatter before being fixed.

In this way, the transfer means during printing applies a voltage of several kilovolts to the discharge wire to generate corona from the wire, and forms an electric field to attract the toner from the latent image forming means to the recording material side, thereby forming an image on the recording material. Transfer it to recording paper. and,
The charge on the portion where the transfer has been completed is gradually removed as the opening and the shielding means move. In this way, during transfer, the toner does not adhere to unnecessary locations on the recording material other than the transfer surface, eliminating the problem of interfering with normal feeding of the recording material.

〔Effect of the invention〕

110- As explained above, in the present invention, by performing static elimination processing after transfer with a simple configuration, the Coulomb force acting on parts other than the photosensitive drum can be weakened on the recording paper. High reliability and safety as there is no problem of paper lifting or adhesion preventing normal paper feeding.

A low-cost optical serial printer can be realized.

[Brief explanation of drawings]

FIG. 1 shows an optical serial printer which is an embodiment of the present invention, FIG. 2 shows a print head of the optical serial printer, and FIG. 3 shows a wire discharger in the optical serial printer. FIG. 4 is a diagram showing a conventional wire discharger. DESCRIPTION OF SYMBOLS 1... Photosensitive drum, 2... Charging section, 3... Latent image forming section, 4... Developing section, 5... Cleaning section, 6... Static elimination section, 7... Carriage, 10...Print head, 13
...Transfer charging section, 15...Recording paper, 24...
Discharge wire, 25... Internal fixed shield, 26...
opening, 27... moving frame, 29... roller, 30...
...External fixed shield, 40...Wire discharger.

Claims (1)

[Claims] A rotating latent image means, a charging means for uniformly charging the surface of the latent image means, a latent image forming means for forming an electrostatic latent image according to recorded information, and a latent image forming means for forming an electrostatic latent image according to recorded information. a print head comprising: a developing means for depositing developer on the latent image means; a cleaning means for removing the developer remaining on the latent image means; and a discharging means for removing static electricity remaining on the latent image means; a conveyance means for intermittently conveying a recording material onto which an image developed on the latent image means is transferred; a head moving means for moving the print head in a direction intersecting the conveyance direction of the recording material; An optical serial printer including a transfer means for transferring an image developed by the means to a recording material, which is disposed along the moving direction of the print head, and forms a latent image on the recording material as the print head moves. An optical serial printer characterized in that a shielding means for preventing charging is provided on a surface other than a surface in contact with the means, and the shielding means is synchronized with the movement of a print head.