JPS59176764A - Developing device - Google Patents

Abstract

PURPOSE:To reduce the size of a device by applying a voltage between an electrode, and a dielectric roller and a moving body, and scattering conductive toner which sticks onto the dielectric roller electrostatically over the moving body by electrostatic attractive force. CONSTITUTION:When zinc oxide is used as the photosensitive material 1b of the moving body 1, negative corona is impressed from a high voltage power source 3 to an electrostatic charger 2 to electrostatically charge the entire surface of zinc oxide 1b negatively. Then, a pattern light image is projected by an optical part 4 upon said zinc oxide 1b to form a latent image. Simultaneously, a voltage is impressed to the electrode 8, and dielectric roller 7 and moving body 1 by a high voltage power source 9 so that the side of the electrode 8 is set positvely and the dielectric material 7b of the dielectric roller 7 is polarized to stick conductive toner 5 electrostatically. When the conductive toner 5 on the dielectric rollr 7 faces the moving body 1, electrostatic attractive force operates on the conductive toner 5 to fly to the moving body 1.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a developing device in an image forming apparatus such as a copying machine.

Conventional configurations and their problems Traditionally, developing devices such as copying machines have been developed using magnetic brush developing devices that use two components, insulating toner and carrier, or magnetic brushes that use one component of conductive toner. There is a developing device. These magnetic brush developing devices have the following common drawbacks:
A magnetic roller structure is used to convey the toner while keeping the spike height constant.[2] A fixed or rotating magnet is provided inside the sleeve roller. As a result, the magnetic roller configuration became complicated and the cost increased.

0 When developing with a magnetic brush by causing the toner to stand on a magnetic roller and applying the spiked toner to a moving body for forming an electrostatic latent image, the height of the toner's spikes must be set with high accuracy. If the height is not high enough, the surface of the moving body may be damaged or the electrostatic latent image may not be developed.As a countermeasure,
Magne・y) A blade with good straightness was provided at a position facing the roller, and the gap between the magnet roller and the blade was precisely set. As a result, blade costs and assembly costs have increased.

Furthermore, the magnetic brush developing device using two components has the following drawbacks.

■A mechanism for agitating the toner and carrier for frictionally charging the toner is required, which increases the size and cost of the developing device.○A mechanism for frictionally charging the toner and transporting the toner to the magnetic roller F. It requires gloss and is expensive.
Ta.

○There is some carrier that adheres with the toner on the moving body for electrostatic latent image formation, and the moving body may be damaged by the carrier.
The lifespan of mobile objects has become shorter.

In addition, a problem with magnetic brush developing devices that use - components is that it is necessary to incorporate a magnetic material into the toner, and there is no colorless material for the magnetic material, so it is difficult to create colors. .

Purpose of the Invention The present invention solves the above-mentioned conventional problems, and includes (1)
By using toner as a component, the developing device can be made smaller and the configuration can be made more compact to reduce costs. Developed by
We have developed a developing device that uses static gravity to fly toner toward the moving object without using a magnetic brush developing device, making it easier to adjust the developing device and extending the life of the moving object. (3) The purpose is to provide a 1)% developing device that uses conductive toner without using magnetic material in the toner and enables color development.

Structure of the Invention The developing device of the present invention includes (1) ZnO, Se, etc.
The photosensitive material is coated with a photosensitive material such as [
(3) A dielectric using a dielectric material such as polyester or vinylic acid fluoride, which is located at the exit portion and is located at a position facing the moving body. Body roller (4) is equipped with an electrode provided in the conductive toner stored in the hopper, and a voltage is applied between the electrode and the dielectric roller to transfer the conductive toner onto the dielectric roller. The conductive toner on the dielectric roller is electrostatically deposited, and then a voltage is applied between the electrode and the moving body to bring the electrode and the conductive toner connected to this electrode to the same potential. The electrostatic latent image on the moving body is developed by causing toner to fly to the moving body.

DESCRIPTION OF EMBODIMENTS FIG. 1 shows a side view of a developing device in a first embodiment of the present invention. In the figure, 1 is a moving body, for example, on the aluminum surface of the base 1a, instant lead oxide, selenium, etc.
It is coated with a photosensitive material 1b such as OPC. 2 is a charger, and according to the photosensitive material 1b VC, for example, if the photosensitive material is zinc oxide, fl is negative, and if the photosensitive material is selenium, a positive corona is applied by the high voltage power source 3, and the photosensitive material 1b is charged.
It charges the surface of the Reference numeral 4 denotes an optical section that projects a patterned light image onto the photosensitive material 1b to form a latent image. Reference numeral 5 denotes a conductive toner, and 6 a hopper containing the conductive toner, which has an outlet portion 6a at one end. 7 is a dielectric roller, and the surface of the 7 parts of the metal electrode roller 7a is made of a dielectric material such as polyester or vinylitin fluoride.
A, A-C1 and a position facing the surface of the photosensitive material 1b of the movable body 1. Reference numeral 8 denotes a metal plate electrode, which is provided at a position υ where it comes into contact with the conductive toner 5 stored in the hopper 6. Reference numeral 9 denotes a high-voltage power source B, which applies a voltage between the electrode 8 and the dielectric roller 7a and the base 1a of the movable body 1, thereby discharging the conductive toner 5 from the dielectric roller 7 to the electrode roller 7a. At the same time, the conductive toner 5 electrostatically adhered to the dielectric roller 7 is transferred to the iWj body 1. 10 is a blade, and when the dielectric roller 7 is rotated, Conductive toner 5 electrostatically adhered to dielectric roller 70
This is to regulate the amount of adhesion.

The operation of the developing device of the first embodiment configured as described above will be described below.

In Fig. 1, moving body 1 is shown in order to make the operation easier to understand.
Photosensitive material 1b is explained using zinc oxide. A negative corona is applied to the charger 2 by the high voltage power supply A3 to negatively charge the entire surface of the zinc oxide 1b. Next, a pattern light image is projected onto the negatively charged zinc oxide 1b by the optical section 4 to form a latent image. Meanwhile, a high-voltage power source B is connected between the electrode 8, the dielectric roller 7, and the moving body 1 as shown in the figure.
9, a positive voltage is applied to the electrode 8 side, the dielectric material 7b of the dielectric roller 7 is polarized, and the conductive toner 5 is electrostatically deposited.

Next, although the principle is unknown, in fact, as an experimental fact, when the dielectric roller 7 rotates and the conductive toner 5 electrostatically adhered on the dielectric roller T moves to a position facing the movable body 1, the conductive toner Electrostatic attraction acts on the toner 6 and it flies towards the moving object 1 ]-
Ru. The flying conductive toner is electrostatically attached to the moving body 1 in an electrostatic latent image.8 The above principle also applies to the electrode 8 and its
The conductive toner 5 in the hopper 6 containing the conductive toner 5 on the dielectric roller 7 connected to the dielectric roller 7 has the same potential, and the electric potential between the conductive toner 5 on the dielectric roller 7 and the transfer body 1 It is assumed that electrostatic attraction was generated by the electric field, and the conductive toner 6 on the dielectric roller 7 flew toward the moving body 1.

A second embodiment of the present invention will be described from the second section with reference to the drawings.

FIG. 2 is a side view of a developing device showing a second embodiment of the present invention. In the figure, 1 is a moving body, 2 is a meter, 3 is a high-voltage electric iA, 4 is an optical part, 5 is a conductive toner, 7 is a dielectric roller, 9 is a high-voltage power source B, and 1o is a plate. is similar to the configuration shown in FIG.

The structure of the embodiment differs from that of the embodiment shown in FIG. The operation of this embodiment is the same as that of the embodiment shown in FIG. 1, so the explanation will be omitted.

As described above, according to the second embodiment, the developing device is miniaturized by providing the electrode 8' in a part of the hopper e'.

In the first and second embodiments, the base 1a of the movable body 1 is shown in the shape of a drum, but it may be in the shape of a belt or a plate. Further, as a means for forming an electrostatic latent image on the moving body 1, a charger and an optical section may be used, but a means such as direct latent image recording on the moving body 1 using an electrostatic head may be provided. .

Effects of the Invention The developing device of the present invention includes a moving body on which an electrostatic latent image has been formed, a hopper having an outlet portion at one end and containing conductive toner, and a hopper disposed in the outlet portion that is connected to the old moving body. The device includes a dielectric roller provided in opposing positions and an electrode provided in the conductive toner, and is provided with means for applying a voltage between the electrode, the dielectric roller, and the moving body. Therefore, (1) it becomes possible to use a single-component conductive toner that does not contain a magnetic material, and the stirring mechanism used for conventional two-component toners is unnecessary. Therefore, the developing device is small and has a simple configuration, resulting in lower costs.

(2) Since electrostatic attraction is used to transport and fly the conductive toner, problems such as high precision adjustment of the developing device and the lifespan of the moving body, which are required with conventional magnetic brush developing devices, are eliminated. .

(3) Since conductive toner that does not contain magnetic material can be used, color printing is now possible.

It has such practical effects.

[Brief explanation of the drawing]

FIG. 1 is a side view of a developing device according to a first embodiment of the present invention, and FIG. 2 is a side view of the developing device according to a second embodiment of the present invention. 1... Moving body, 6... Conductive toner, 6
... Ho Pa, 7...-Dielectric roller, 8, 8'.
···electrode. Name of representative JJP Patent attorney Toshio Nakao and one other person Figure 1 Figure 2

Claims (2)

[Claims] (1) A moving body on which an electrostatic latent image has been formed, a hopper having an outlet at one end and containing conductive toner, and a dielectric provided at the outlet and at a position facing the moving body. The conductive toner includes a roller and an electrode provided in the conductive toner, and a voltage is applied between the electrode and the dielectric roller and the moving body to cause the toner to electrostatically adhere to the dielectric roller. A developing device characterized in that the conductive toner is caused to fly to the moving body by electrostatic attraction. (2) The developing device according to claim 1, wherein a part of the hopper that is in contact with the conductive toner in the hopper is constituted by the electrode.