JPH08114985A - Developing device - Google Patents

Abstract

PURPOSE: To surely carry non-magnetic one-component system developer with a simple mechanism, to sufficiently impart an electric charge, and to make a developing device thin. CONSTITUTION: When an excitor 4 is driven, a developer guiding board 2 vibrates in a vibrating waveform that the developer T is rolled by the vibration transmitted from an actuator 4a, and the developer T passes through the upper surface of the board 2, a developer housing part, and a developer controlling film 5, and is vibrated and carried in the direction of a developer carrier 6. Especially, the developer T having passed through the film 5 is charged by the friction up to a sufficient voltage value by frictional contact repeated more than several times between the surface of the board 2 and the developer while being rolled. The frictionally charged developer T is carried on the board 2 to a part close to the carrier 6 and a thin layer is formed on the carrier 6. The thin layer of the developer T on the carrier 6 moves to the image part of an electrostatic latent image on the carrier 10 so as to visualize the electrostatic latent image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device for visualizing an electrostatic latent image with a developer, and more particularly to a developing device using a non-magnetic one-component type developer.

[0002]

2. Description of the Related Art In a conventional developing device using a non-magnetic one-component developer, the developer transport and the triboelectric charging are performed by different mechanisms. That is, the developer was stirred by the stirrer and sent to the supply roller, conveyed from the supply roller to the developer carrying roller, and further carried to the surface of the electrostatic latent image carrier. Further, the triboelectrification of the developer is performed by a blade that is pressed against the developer carrying roller.

[0003]

In the above-described conventional developing device using the non-magnetic one-component type developer, the developer is conveyed by the combination of the rotating mechanism, so that the mechanism is complicated. And the rotating load increases,
There is a problem that it is difficult to reduce the size of the developing device, and particularly to reduce the thickness.

Further, since the frictional charging of the developer is performed by one blade, there are problems that the charging efficiency is low and uniform charging is difficult.

In view of the above points, an object of the present invention is to make it possible to reliably convey a non-magnetic one-component type developer with a simple mechanism, to impart a sufficient charge, and to achieve a thin structure. To provide a developing device.

[0006]

SUMMARY OF THE INVENTION In a developing device of the present invention, a charged non-magnetic one-component type developer is attached to the surface of an electrostatic latent image carrier via a developer carrier to form an electrostatic latent image. In a developing device for visualizing an image, a vibrating type having a mechanical vibration guide portion that vibrates and conveys a developer from a developer storage portion to a developer carrier and that vibrates and contacts the developer to provide triboelectrification. It is characterized by having a developer transport mechanism.

[0007]

In the developing device of the present invention, the mechanical vibration guide portion of the vibration type developer conveying mechanism vibrates and conveys the developer from the developer accommodating portion to the developer carrier, and vibrates and contacts the developer to cause friction. Give a charge.

[0008]

The present invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional view showing the structure of a developing device according to the first embodiment of the present invention. The developing device of this embodiment is
A developer cartridge 1, a developer guide plate 2, a plurality of leaf spring members 3, a vibrator 4, a developer regulation film 5, a developer carrier 6, a layer thickness regulation film 7, and a developer. A power supply E1 for applying a bias voltage to the carrier 6 and a power supply E2 for applying a bias voltage to the developer guide plate 2 constitute a main part thereof. The developer guide plate 2, the leaf spring member 3, and the vibrator 4 constitute a vibration type developer transport mechanism. In FIG. 1, reference numeral 10 indicates an electrostatic latent image carrier, and T indicates a non-magnetic one-component developer.

The developer cartridge 1 is made of plastic,
The casing 1 is formed of a material such as paper and has a substantially flat rectangular parallelepiped shape, and the partition wall 1a is provided so as to hang down toward the inner front end (the left end in FIG. 1). In the developer cartridge 1, the rear end side (right end side in FIG. 1) divided by the partition wall 1a is a developer accommodating portion, and the front end side (left end side in FIG. 1) carries the developer. It is a space for disposing the body 6.

The developer guide plate 2 includes a developer cartridge 1
It is provided horizontally near the bottom of the inside, and airtightly partitions the upper developer storage portion and the installation space of the lower leaf spring member 3. For example, when the developer T is a styrene / acrylic type or a polyester type, the developer guide plate 2 is plated with a metal such as copper, aluminum or the like from a frictional charging sequence or a suitable engineering plastic such as polymethylmethacrylic or the like. Formed of a composite material.

The leaf spring member 3 is formed by bending a film-shaped thin metal plate, and is formed on the lower surface side of the developer guide plate 2.
The developer guide plate 2 is disposed above the corner and supports the developer guide plate 2 at a position near the bottom of the developing cartridge 1 so as to be vibrable.

The vibrator 4 is formed of a piezoelectric vibration element, and specifically, a small vibrator which is commercially available for a buzzer or pager is used. The shaker 4 is fixed to a fixing member separate from the developer cartridge 1,
The actuator 4a extends through a through hole formed in the developer cartridge 1 so as to come into contact with the lower surface of the developer guide plate 2. The shaker 4 vibrates at a frequency of about 10 to 100 Hz at a DC voltage of V, and the tip of the developer T that is in contact with the developer guide plate 2 due to the vibration transmitted to the developer guide plate 2 via the actuator 4a. A vibration waveform is generated such that the developer T, which is conveyed to the side (the left end side in FIG. 1) and is in contact with the developer guide plate 2, rolls. This vibration waveform is, for example, as shown in FIGS. 3A to 3C, a continuous sine wave, a sawtooth wave, or a single cosine wave that is continuous in the direction parallel to and perpendicular to the conveyance direction of the developer T. It is desirable that

The developer regulating film 5 is provided in the developer cartridge 1
An upper end is attached to a partition wall 1a provided inside and a lower end is curved toward the front end side (the left end side in FIG. 1) and is elastically contacted with the developer guide plate 2, and an unnecessarily large amount of the developer T In order to prevent the developer from flowing out of the developer accommodating portion, the pressing force that allows only the sufficiently charged developer T to pass is applied to the developer guide plate 2. The developer regulating film 5 is, for example, a polyethylene terephthalate film, a polyimide (nylon) film, or a metal vapor deposition film of aluminum, copper or the like formed on the surface of these films, and the thickness is 0.01 to 0.1 mm.
Has been created to the extent. A power supply (not shown) for injecting charge may be connected to the developer regulating film 5.

The developer carrying member 6 is composed of a conductive cylindrical body whose main component is a polymer or paper material which is elastically deformable in the diametrical direction, and one of the outer peripheral surfaces faces the tip of the developer guide plate 2. So that the other of the outer peripheral surfaces is the developer cartridge 1
It is rotatably arranged near the tip of the developer cartridge 1 so as to be close to or in contact with the surface of the electrostatic latent image carrier 10 through the tip opening. Although the rotation speed of the developer carrying member 6 varies depending on the diameter of the developer carrying member 6, the peripheral speed is set to be equal to or higher than the peripheral speed of the electrostatic latent image carrying member 10 in order to secure the image density. It is preferable to leave it.

The layer thickness regulating film 7 is formed of an elastic thin film such as plastic, and is used as the developer cartridge 1.
It is provided on the bottom surface side near the front end opening inside, and serves to regulate the layer thickness of the developer T on the developer carrier 6 to a certain level or less.

The polarities of the power supplies E1 and E2 are the same as the charging polarity of the developer T, and the voltage is set to about -20 to -600 V in the case of negative charging. However, the voltage is set so as to satisfy the relationship of | E1 | <| E2 |. Hereinafter, the charging polarity of the developer T is assumed to be negative.

Next, the operation of the developing device of the first embodiment thus constructed will be described.

With the start of the operation of the developing process, the vibration exciter 4 is driven, while the developer carrier 6 and the electrostatic latent image carrier 10 are each rotated in the direction of the arrow.

When the vibrator 4 is driven, the developer guide plate 2 vibrates in a vibration waveform such that the developer T rolls on the developer T due to the vibration transmitted from the actuator 4a of the vibrator 4 and the developer guide plate 2 The developer T which is in contact with is conveyed along the upper surface of the developer guide plate 2 from the developer accommodating portion through the developer regulating film 5 and is vibrated and conveyed toward the developer carrier 6. In particular, the developer T that has passed through the developer regulating film 5 is frictionally charged to a sufficient voltage value by repeated frictional contact with the surface of the developer guide plate 2 several times while rolling. The triboelectrically charged developer T is carried on the developer guide plate 2 to a portion in the vicinity of the developer carrier 6, and forms a thin layer on the developer carrier 6.

The thin layer of the developer T formed on the developer carrying member 6 has its layer thickness regulated by the layer thickness regulating film 7 as the developer bearing member 6 rotates, and then an electrostatic latent image is formed. The electrostatic latent image carrier 10 is conveyed to the developing area for development, and the electrostatic latent image carrier 10 is transferred through the tip opening of the developer cartridge 1.
Will be in close proximity or in contact with.

In the developing area, since the surface charge densities of the image area and the non-image area of the electrostatic latent image on the electrostatic latent image carrier 10 are different, the charge amount of the developer T is q and the developing area is When the electric field at the position is E, the force F = qE acting on the developer T is different between the image portion and the non-image portion of the electrostatic latent image, and the developer T is transferred from the developer carrier 6 only in the image portion. Development is performed by moving to the electrostatic latent image carrier 10 side.

Further, the developer T on the developer carrying member 6 which has not been used for developing is used again for developing together with the rotation of the developer carrying member 6.

By repeating the above operations, the developing process proceeds.

FIG. 2 is a sectional view showing the structure of the developing device according to the second embodiment of the present invention. The developing device of this embodiment is
A plurality of developer guide plates 2 are vertically spaced from each other (3 in the figure).
It is arranged. Through holes 2a through which the developer T can flow are formed near the rear ends of the upper two developer guide plates 2. A plurality of developer regulating films 5 are also provided so as to elastically contact each developer guide plate 2. Since the other members not particularly mentioned are configured similarly to the corresponding members of the developing device of the first embodiment shown in FIG. 1, the corresponding members are designated by the same reference numerals. Detailed explanation is omitted.

In the developing device of the second embodiment having such a configuration, although the number of the developer guide plates 2 increases and the amount of the developer T to be conveyed increases, the others are the same as the first embodiment shown in FIG. It goes without saying that the developing device operates similarly to the developing device of the embodiment.

In each of the above-mentioned embodiments, the case of the developing device using the negative charging type developer T has been described, but the present invention is also applicable to the developing device using the positive charging type developer T. Needless to say, it is applicable to.

Although DC power supplies are shown as the power supplies E1 and E2, it is also effective to use a (DC + AC) superimposed power supply for preventing the developer T from aggregating and improving the transportability. is there. However, even if the alternating current is superposed, the developer T
It is necessary to have a direct current component such that the polarity of does not change.

[0029]

As described above, according to the present invention,
A vibrating developer transport mechanism having a mechanical vibration guide portion for vibrating and transporting the developer from the developer storage portion to the developer carrier and vibratingly contacting the developer to frictionally charge the developer is provided. As a result, there is an effect that both reliable transport of the developer and sufficient triboelectrification can be simultaneously obtained with a simple structure.

Further, since the rotating mechanism in the developing device, especially the stirring mechanism is not required, there is an effect that the developing device can be made significantly thinner than the conventional one.

[Brief description of drawings]

FIG. 1 is a sectional view showing a configuration of a developing device according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing the structure of a developing device according to a second embodiment of the present invention.

3 (a) to 3 (c) are diagrams illustrating waveforms of vibrations applied to a shaker in the developing device of FIGS. 1 and 2. FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 developer cartridge 1a partition wall 2 developer guide plate 2a through hole 3 leaf spring member 4 vibrator 4a actuator 5 developer regulating film 6 developer carrier 10 electrostatic latent image carrier E1, E2 power source T developer

Claims (4)

[Claims] 1. A developing device for visualizing an electrostatic latent image by adhering a charged non-magnetic one-component type developer to the surface of the electrostatic latent image carrier via a developer carrier. A vibrating developer transport mechanism having a mechanical vibration guide portion for vibrating and transporting the developer from the developer accommodating portion to the developer carrier, and vibratingly contacting the developer to impart frictional charging. Development device. 2. The mechanical vibration applied to the mechanical vibration guide is a continuous sine wave, a sawtooth wave, or a single cosine wave continuous in the direction parallel and perpendicular to the developer conveying direction. Item 1. The developing device according to item 1. 3. The developing device according to claim 1, wherein the mechanical vibration guide portion is made of a material selected from a triboelectric charging sequence suitable for generating a charge of the developer. 4. The developing device according to claim 1, wherein the mechanical vibration guide portion is composed of a single or a plurality of developer guide members.