CN102262371A - Novel development mode of laser printer - Google Patents

Abstract

The invention relates to the fields of laser printer and copying machine, and provides a novel development mode. The development elements of the present invention comprise a pressure roller [1], a magnetic roller [2], a powder controlling rubber cutter [3], a sensitometric drum [4] and a charging roller [5]. In the process of operating, the voltage is externally added on the pressure roller [1] and is not added at the two ends of the magnetic roller [2], ink powder possesses high electric energy under the dual effects of the pressure roller [1] and the powder controlling rubber cutter [3], so that the development polar ink powder can overcome the attractive force of the magnetic roller and the magnetic core as well as minimal gap between the magnetic roller and the sensitometric drum for being absorbed by a static latent image of the sensitometric drum, and then transfer to the sensitometric drum for developing. The invention relates to the novel development mode of the laser printer, and is capable of reducing the rolling torque, minimizing the damage of the core assemblies, substantially raising the stability of work, substantially reducing the cost and the like.

Description

The new visualization way of laser printer

One, technical field

The present invention relates to the developing device of duplicating machine, laser printer, particularly the visualization way of laser printer.

Two, background technology

Now, the visualization way of laser printer mainly contains two kinds, and jump type developing and contact are developed.At first, developing with Hewlett-Packard's one-component magnetic powder is example, and the principle of work of the development of beating is as follows: its developing apparatus adopts magnetic roller, and the magnetic roller is made up of the rotating aluminium sleeve of fixed magnetic core stick in the inside and outside.Ink powder is adsorbed on aluminium cover surface and makes ink powder charged along with the rotation of aluminium cover and with scraper plate is tangent with the generation friction owing to being subjected to the magnetic field force effect during work, and scraper adopts the rubber material.Simultaneously the aluminium cover is by the sheath at two ends or protect the distance that wheel and photosensitive drums keep about 0.30mm.In addition, magnetic roller aluminium puts the development bias voltage that is added with an alternation, and alternating voltage is about-800v～800v, DC voltage pact-600v.The bias voltage of this stack changes the electric field force fluctuation that ink powder is subjected to, when alternating voltage for negative, electric field force increases, and makes toner particles can overcome the attraction of permanent magnet in the magnetic roller, jump gaps and going to the electrostatic latent image of photosensitive drums; When alternating voltage is timing, electric field force reduces, and any toner particles that may not be filled on the electrostatic latent image is pulled back, and finishes developing process.Because carbon dust can initiatively be adsorbed onto on the magnetic roller, therefore need not to increase again device powder feeding on the magnetic roller.Comparatively speaking, in the laser printer that contact is developed, with the Samsung is that example has big powder storehouse usually, the interior ink powder limit being continued with puddle support constantly is defeated by powder feeding roller, because developer roll must lean on the continuous turning handle powder of powder feeding roller to deliver to above it, so powder feeding roller is many with there being the porosint of certain resistance to make.When imposing the voltage of pact-500V, can make ink powder generate electronegativity to powder feeding roller.Developer roll mostly is metal-cored rubber roll, and very big bulk resistor is arranged, to its impose and-during the voltage of 300V, will transfer on the high developer roll of relative current potential for the charged toner on the powder roller.Elastic metallic scraper and developer roll keep minimum gap, and it also is subjected to an alternating voltage, can constantly make the ink powder activation and it is spread to very thin one deck uniformly in the vibration.Photosensitive drums graphics field after exposure through the charging roller charging can produce the higher relatively electrostatic latent image of current potential.With the developer roll contact process in, ink powder can be adsorbed to the higher part of current potential on the photosensitive drums, electrostatic latent image changes visual ink powder image into, simultaneously developer roll is added a DC voltage, and unnecessary ink powder is adsorbed back developer roll, this is a developing process.This visualization way requires photosensitive drums directly to contact with developer roll, and bigger to the damage of photosensitive drums, driving torque is also big.

Three, summary of the invention

The object of the present invention is to provide a kind of new visualization way, can be used for improving in the laser printer the big deficiency that waits of contact development moment of torsion, can significantly reduce cost simultaneously.Its particular content is:

The present invention is made up of pressure roll, developing magnetic roll, rubber powder delivery cutter, charging roller and photosensitive drums etc.At first, pressure roll is subjected to certain voltage when work, it is corresponding electrical that close with it ink powder is induced, assurance is adsorbed to enough electric weight on the carbon dust band that magnetic roller aluminium puts, carbon dust turns to control powder rubber tapping knife position with the aluminium cover, carbon dust can be spread to uniform one deck under the effect of rubber tapping knife, simultaneously because friction also can increase the carbon dust carried charge.The ink powder of carried charge abundance increases the carbon dust height because the effect of high-intensity magnetic field can form the magnetic fringe when arriving the development utmost point of magnetic roller, help carbon dust and jump to photosensitive drum surface, be recharged the electric charge that roller evenly fills with this moment on the photosensitive drums and under laser radiation, on photosensitive drums, formed electrostatic latent image, the carbon dust of sub-image district correspondence can overcome the magnetic field force of magnetic roller and be adsorbed onto photosensitive drum surface under electrostatic forcing, non-development district carbon dust is still attached left magnetic roller surface and can not arrive photosensitive drum surface under magnetic field force and electrostatic repulsion acting in conjunction then, thereby finishes development.

Feature of the present invention is that developing magnetic roll directly contacts with photosensitive drums is non-, and left magnetic roller aluminium puts and does not add any voltage, there is a pressure roll of being made by elastic body magnetic roller below, certain in addition to pressure roll in the course of the work voltage, near charged pressure roll also can make ink powder induces corresponding electric charge, thereby guarantees that the ink powder that is adsorbed onto on the magnetic roller can have higher electric weight.What the control powder adopted is the rubber scraper, and it can spread to very thin uniform one deck with magnetic roller surface ink powder, also can make it fully charged with the ink powder friction.

Core of the present invention is exactly how to guarantee to allow the charged abundance of carbon dust and evenly, so that directly do not contact with photosensitive drums and carbon dust is not subjected to finish development under the situation of any extra electric field power under the acting in conjunction of electrostatic force and magnetic field force at carbon dust.

Advantage of the present invention is to avoid developing element directly to contact the infringement that is produced with photosensitive drums, rotates light wearing and tearing and the bigger driving torque of having eliminated when core component is worked, and improves stability greatly, can reduce cost effectively again simultaneously.The present invention can be used for Samsung, in the repacking of a series of contact development such as brother laser printer.

Four, description of drawings

Fig. 1 is the simple and easy schematic diagram of laser printer developing process of the present invention.

[1] expression pressure roll among the figure, [2] expression developing magnetic roll, the rubber scraper of [3] expression control powder delivery, [4] expression photosensitive drums, [5] expression charging roller.

Five, embodiment

Below in conjunction with accompanying drawing the present invention is further described.Ink powder in the powder storehouse arrives pressure roll [1] surface under puddle support stirs, the impressed voltage during pressure roll [1] work can make electric weight certain on the ink powder band.They are developed the last powder utmost point absorption of magnetic roller [2] in the nearest position of distance developing magnetic roll [2], with the aluminum pipe rotation of magnetic roller.Ink powder is spread to very thin and uniform one deck through control powder rubber tapping knife [3] time, and the friction with rubber tapping knife [3] has also increased its carried charge in addition, and ink powder rotates to the development utmost point with sleeve afterwards.Photosensitive drums [4] obtains higher surface potential after charging roller [5] charging, can form sightless electrostatic latent image at visuals after the exposure.The development pole span of magnetic roller [2] is very near from photosensitive drums [4], and the upright powder height of ink powder extremely go up of developing this moment is higher, and carried charge is also big, thus the ink powder grain to be subjected to the Electrostatic Absorption power of electrostatic latent image also big, can overcome the attraction of magnetic roller [2] and transfer to photosensitive drums [4] surface.So far finish the development course of work.

Claims (8)

1. the visualization way of a laser printer, it is characterized in that: in developing process developing apparatus and photosensitive drums from, this photosensitive drums is formed with electrostatic latent image by on charging unit charging and its, impelling ink powder on the developing apparatus to skip between developing apparatus and the photosensitive drums gap is that the electrostatic latent image district and does not add the electric field force that photosensitive drums is pushed powder in assistance to the Electrostatic Absorption power of charged toner on the photosensitive drums to the power on the photosensitive drums.

2. visualization way according to claim 1 is characterized in that developing apparatus adopts the magnetic roller, and ink powder adds the carbon dust mode with magnetic single component powder or magnetic carrier, and the spacing between magnetic roller and the photosensitive drums is between 0-0.40mm.

3. visualization way according to claim 2, it is characterized in that, because magnetic roller aluminium puts and do not add assistance powder is pushed to the electric field force of photosensitive drums, so carbon dust must be with enough electric weight could jump gaps, so need add pressure roll correspondence with it below the left magnetic roller.

4. visualization way according to claim 3 is characterized in that pressure roll is to be made by the elastic body of metal-cored one or more layers rubber-like of coated outside, and pressure roll can contact also separable with the magnetic roller.

5. visualization way according to claim 3, it is characterized in that: in the course of work pressure roll is added a corresponding voltage, make the carbon dust between pressure roll and magnetic roller fill certain electric weight with and be adsorbed onto magnetic roller surface in some way, simultaneously because pressure roll has certain pressure with the magnetic roller to the carbon dust between the two, thereby feasiblely can obtain higher frictional electrification amount by the carbon dust between them.More than two kinds of factors can make electric weight enough on the carbon dust band.

6. visualization way according to claim 5, it is characterized in that: can be filled with by pressure roll uniformly for making the carbon dust that is adsorbed onto magnetic roller surface in a certain way, smooth, the smooth atresia of pressure roll surface requirements, but also be not limited to the above requirement, and pressure roll is rotatable also can not rotate to the pressure roll surface.

7. visualization way according to claim 2 is characterized in that controlling accordingly the powder cutter and adopts rubber tapping knife.

8. visualization way according to claim 7, it is characterized in that, rubber tapping knife can make the carbon dust on magnetic roller surface even, control magnetic roller strap powder amount, with advancing to make by the carbon dust between rubber tapping knife and the magnetic roller because friction is with more, but because the magnetic roller has and do not add any assistance voltage, so carbon dust is not subjected to any add, receipts powder electric field force of pointing to magnetic roller surface.Given this, the band powder amount on magnetic roller surface will be lacked under the prerequisite that satisfies the development needs as much as possible, to avoid producing other problems such as bottom ash.This point has the visualization way of beating of extra electric field different with the magnetic roller.

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