JPS5891476A - Developing device - Google Patents

Abstract

PURPOSE:To increase the charging amount of toner sufficiently and uniformly, and to perform development freed of ground, staining by applying a bias voltage between a doctor blade and a sleeve or rubber layer to implant charge to magnetic toner. CONSTITUTION:Toner 10 selected on a rubber layer 1 by frictional resistance and frictional charging as a sleeve 2 rotates is charge implanted to be charged and formed in a thin red layer when passing by the tip of a doctor blade 8. The thin red and charge implanted layer of charged toner 10 formed by the blade 8 is carried to the surface of a recording medium 9 to develop reversally by the toner on a developing roll surface raised up to said charge potential by a bias voltage vR. In this case, the charging polarity of the toner 10 is equal to that of a ground potential and the toner 10 is charge implanted uniformly by the blade to attain an uniforms polarity and to cause no staining.

Description

[Detailed description of the invention] TECHNICAL FIELD The present invention relates to a toner transfer device using a toner transfer device.

In general, in an image recording system that employs electrophotography or electrophotographic processes, a recording medium on which a electromagnetic latent image is formed by a magnetic toner with a high resistance component. In order to obtain high-quality recorded images with high image density without causing background stains when using a toner, it is necessary to increase the quality of the toner.

In particular, in a 11m1 recording system that uses a transfer type that uses a 11° dielectric material, it is difficult to remove the heat as a pretreatment for the recording medium made of 11° dielectric material, so it is difficult to uniformly print the recording medium. After that, a single pressure is applied with the stylus to form a latent layer with #drink, and the layer is reversed in the direction of the recording medium where it was formed. However, in this case, if the Toner Emperor 1111] li is low, there will be problems if the background stains become severe and the degree of irrigation does not decrease.

Therefore, conventionally, in the current device, magnetic toner is held on a sleeve made of a non-magnetic metal plate that rotates around a fixed magnetic roller to form an anaerobic brush. Although the banding of the toner is made to occur by applying a % pressure to the surface of the toner, it is not possible to make the banding of the toner sufficiently by applying such voltage alone.

This %4 was made with the above points in mind.

The unique structure ensures that the charging type of toner supplied to the surface of the recording medium is sufficient, allowing development processing to be performed at high levels without causing skin stains. Hereinafter, an embodiment of the invention will be described in detail with reference to the accompanying drawings.

According to the present invention, as shown in FIG. A sleeve 2 consisting of a sleeve 2 and a guide roller 1 provided on the plate of the case 30 are arranged so as to be able to slide on the guide rollers 4 and 5 by a force F by a spring 6.
I was caught up in the measurement.

And by the spring 7, the rubber layer 11111 is
The doctor blade 8 is pressurized in the normal direction to the rubber layer 1, and the doctor blade 8 is attached so that its tip lightly contacts the rubber layer 1. A bias voltage V is applied to the S1 sleeve 2 (or $11C rubber layer 1), and
A bias voltage vD is electrically applied to the threshold between the sleeve 2 (or the conductive rubber layer 1) and the doctor blade 8. Also.

In the figure, 9 comes into contact with rubber 1-1 while moving in the direction of the arrow [
It shows a belt-shaped recording medium made of a dielectric film or a photoreceptor film that is subjected to a long-term development process using the supplied toner 10. Further, the specific resistance of the rubber layer l is 1
It is effective within the range of 0 to lOg·picture, and silicone rubber is used as the rubber material.

Chloroprene rubber, polyurethane rubber, etc. are used.
The layer thickness is set to be approximately 0.5 to 5 mm.

However, the current gI according to the present invention purchased in this way!
In the device, as the sleeve 2 rotates, the rubber layer 1 is carried by the frictional resistance 2 and the toner 10, and when the toner 10 passes the tip 4 of the doctor blade 8, an electric charge is injected into the band. In addition, the layer is made thinner. @
FIG. 2 shows the charging characteristics of the toner 10 during charge injection. Generally, the larger the bias voltage VD and the larger the resistance value of the toner 10, the larger the amount of charge. Also, some toner lO particles have a polarity sum that does not necessarily cross the zero point. Also, the tip of the doctor blade 8 4! The thickness of the toner when passing through is
The smaller the chance of contact between the doctor blade 8 and each toner particle, the higher the charge injection efficiency. Since the toner 10 used here is a magnetic toner, it contains iron powder and the like.

A toner in which iron powder with a small particle size is scattered in order to prevent a short circuit between the rubber layer l and the doctor blade 8 and increase the efficiency of charge injection into the toner 10? It is desirable to use it.

In this way, the toner 10 that is thinned and efficiently injected by the doctor blade 8 is transported to the recording medium 91ii, where it is raised to the precharge magnetic potential by the bias voltage vl, and the toner on the surface of the developing roller IC means that reversal development is performed on the surface of the recording medium 9. At this time, the charged polarity of the toner 10 is
Needless to say, it has the same polarity as the skin potential (first precharge) of 1ii.

In addition, since the toner 10 supplied to the surface of the recording body 9 is uniformly injected with electric charge by the doctor blade 8, its polarity is adjusted to the band cover 8, and the toner becomes floating toner, which causes background stains. The probability of this occurring is effectively reduced. moreover,
The current 11' 4th position is v1 + the amount of hidden charge injected into the toner IO, so +@##hidden is also the same as above.In the case of S1 reversal mass development %
Valley bias voltage VD,V.

The polarity is the same as the background # of the medium 9 surface, and in the case of forward development, the ground potential (same potential as the conductive layer 4 of the recording medium 9) is good (s V The polarity is opposite to the potential of the Dkl recording unit 9+ft+. Also, a foot of Dro pressure f from the 11 spring 7 is applied to the doctor blade 8.
, and because it is pressed onto the guide roller 4.5 by the action of the spring 6, the pressure force of the doctor blade 8 is increased by the friction force generated between the doctor blade 8 and the rubber 41. Fluctuations and wobbling of the toner are effectively suppressed, and the doctor blade 8 can always perform stable charge injection 2 and uniform toner layer thinning.

r, Kst*kJ The medium 9 is partially wrapped around the rubber layer 1 20, so that the current Il! Time K
JD blowing nip l! Since the image density can be increased, the image density can be improved, and the position of the sleeve 20 relative to the recording medium 911 can be made coarser. In addition, when developing the surface of the recording medium 9, the llk excitation speed of the recording medium 9 is vl, and the rotation speed of the sleeve 20 is d.
) jj When V 2, the speed ratio is V 2/V
By setting the value to 1-1 to 3JfMFIL, good development processing can be performed.

In addition, Figure 3 shows another embodiment of the present invention, in which the doctor blade 8 is directly attached to the case 3 so that a gap is formed between the tip of the doctor blade 8 and the rubber layer l.
The installation is fixed.

With this configuration, a high assembly degree 8 and component precision are required when installing the doctor blade 8 to the case 3&C in order to secure the necessary gap, but due to non-contact, This has the advantage that the durability of the rubber layer 1 is improved.Furthermore, Fig. 4 S and Fig. 5 show other embodiments of the present invention, and in these cases, the inside of the G1 sleeve 20 is It is constructed by providing a pair of mag rollers 11 with a plurality of magnetic poles M and a pair of mag rollers 11 which are arranged so that a uniform magnetic field is formed in the axial direction. , the toner 1 is simply created by only the S abrasive force 2 and the friction band between the rubber 1 and the toner lO.
O) 111-If the toner is fed twice to the 9th surface of the recording medium, the conveying force is weak, and in order to prevent uneven development due to toner cutting, part of the magnetic action of the mag roller 11 is used to feed the toner.・Liu 1 The effect of injecting brazing into the toner 10 is greatly reduced, but the conductive rubber layer l
It is also possible to use only the sleeve 2 to form the bottom of the gap roller without specifically providing the groove.

In the present 11 apparatus according to the present invention, a belt-shaped recording medium [contacting] on which an electrostatic plate is formed is used.

A sleeve is provided with a conductive rubber layer on the outer periphery that is rotationally driven, and a mag roller of a constant radius is provided inside according to the necessity, and the toner is cut into ears according to the rotation of the sleeve. It consists of a doctor blade that adjusts fJ, and is designed to inject a load into the image quality toner by applying a bias/one pressure between the doctor blade and the pickpocket, -b, or 61 rubber layer. The toner applied to the surface of the recording medium is sufficiently and uniformly charged and electrified. It is a great advantage to be able to perform a good filtration process on a recording medium with a 5 degree sieve.

[Brief explanation of the drawing]

Structure 1 Figure G1 is a simplified configuration diagram showing the current theory according to one embodiment of the present invention; FIG. 5 is a simplified configuration diagram showing another embodiment of the present invention. l... Conductive rubber layer 2... Sleeve 3... Case 4, 5... Guide rollers 6, 7... Spring 8-... Doctor blade 9-... Recording medium 1
0... Image quality toner Rubber... Magroller Figure 1 Figure 2 ↑

Claims (1)

[Claims] 1. A sleeve formed with a magnetic toner, which is in contact with the belt-shaped recording medium and is rotationally driven; , one charge is injected into the toner by the applied voltage? The current # with a doctor blade that can be attached! Apparatus: The bridge portion 4&straight according to the description in item 1 above, in which the outer periphery of the λ sleeve is coated with a rubber skin of 5% mold. 3. The present device according to the above-mentioned 1sA or 2nd section of the 2nd paragraph, in which a mag roller fixed to the inside S of the sleeve is provided.