JPH02199484A - developing device - Google Patents

Abstract

PURPOSE:To hold the amount of toner for development constant and to maintain excellent picture quality by varying the electric field between the conductive base of a toner carrier and a toner conveyance quantity control member according to environmental variation in temperature, humidity, etc. CONSTITUTION:The toner carrier 9 which has an insulating layer 11 formed on the conductive base 10 for carrying toner is provided adjacently to a latent image carrier 1 where an electrostatic latent image is formed. The conductive toner conveyance quantity control member 12 is provided adjacently to the carrier 9 and a voltage applying means 14 applies an electric field between the member 12 and base 10 to stick toner on the carrier 1 electrostatically, visualizing the electrostatic latent image. At this time, a temperature and humidity variation detector 19 installed in a developing unit 7 detects the variation in the environment in the unit to vary the electric field between the base 10 and member 12 corresponding to the environmental variation, thereby holding the amount of toner for development constant.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a developing device that forms an image using non-magnetic toner.

[Prior Art] A conventional developing device is disposed adjacent to a latent image carrier that forms an electrostatic latent image, as shown in Japanese Patent Application No. 63-91000, and conveys toner, which is an image forming body. It has a toner transport body in which an insulating layer is formed on a conductive support, a conductive toner transport amount regulating member is disposed adjacent to the toner transport body, and the conductive support and the toner transport An electric field is applied by a voltage applying means between the amount regulating member and the toner on the toner conveying member to electrostatically adhere to the latent image carrier to visualize the electrostatic latent image. Met.

[Problems to be Solved by the Invention] However, with the above-mentioned conventional technology, there is a problem that development characteristics such as development density change due to changes in the environment such as temperature and humidity, making it difficult to always obtain good images. It had a point.

The present invention is intended to solve these problems, and its purpose is to develop a one-component non-magnetic development method that enables image formation without deteriorating image quality due to environmental changes such as temperature and humidity. The company provides a developing device.

[Means for Solving the Problems] The developing device of the present invention is arranged adjacent to a latent image carrier that forms an electrostatic latent image, and on a conductive support that conveys toner as an image forming body. a toner transport body on which an insulating layer is formed; an electrically conductive toner transport amount regulating member is disposed adjacent to the toner transport member; and a conductive toner transport amount regulating member is provided between the conductive support and the toner transport amount regulating member. In the developing device, an electric field is applied by a voltage applying means to cause the toner on the toner conveying member to electrostatically adhere to the latent image carrier to visualize the electrostatic latent image. The present invention is characterized in that the electric field between the body and the toner transport amount regulating member is changed in response to changes in the environment.

The developing device of the present invention is characterized in that the environment is a temperature environment.

The developing device of the present invention is characterized in that the environment is a humid environment.

[Function] According to the above configuration of the present invention, the amount of toner to be developed can be kept constant by changing the electric field between the conductive support and the toner transport amount regulating member in response to changes in the environment, etc. can be kept. As shown in FIG. 2, the amount of toner developed by the developing device of the present invention changes depending on the change in the electric field between the conductive support and the toner transport amount regulating member.

The amount of toner to be developed tends to increase as the temperature and humidity increase, so we developed a conductive support and toner that can detect changes in temperature and humidity and compensate for changes in the amount of toner to be developed. By changing the electric field between the toner and the conveyance amount regulating member, the amount of toner to be developed can be kept constant.

Hereinafter, the present invention will be explained in detail with reference to Examples.

Embodiment 1 FIG. 1 is a cross-sectional schematic view of a developing device in an embodiment of the present invention.

The latent image carrier 1 has a photoconductive layer 3 coated on a conductive support portion 2 . Charger 4 charges photosensitive layer 3
The light emitted from the light source 5 such as a laser is charged to a predetermined potential by a rotating polygon mirror or the like (not shown).
An electrostatic latent image was formed on the latent image carrier 1 by scanning the photosensitive layer using the image forming optical system 6 and forming an image on the photosensitive layer 3 to obtain a potential contrast. On the other hand, the developing device 7 charges the toner 8, which is an image forming member, and transports the toner 8 with a toner transporting member 9. The toner conveying body 9 has a thin insulating layer 11 formed on a conductive support 10. Adjacent to the toner conveying body 9, a conductive cylindrical sleeve 12 and a toner conveying amount regulating member are arranged adjacent to the toner conveying body 9. An electrically conductive and flat blade 13 is disposed as a transport amount regulating member, and a voltage applying means 14 is connected between the electrically conductive support 10 and the sleeve 12 and between the electrically conductive support 1.
0 and the blade 13 to generate a high electric field in each gap to reduce the insulation resistance of the toner 8, charge is injected into the toner 8 from the sleeve 12 and the blade 13, and the toner 8 is Charge to a predetermined amount of charge. A temperature change detector 19 installed in the developing device 7 detects that the sleeve 12 and the conductive support 1 are connected due to temperature changes in the developing device 7.
The magnitude of the electric field applied between 0 and 0 is varied. The toner 8 adhering to the sleeve 12 is peeled off by the scraper 15 to prevent the toner 8 from agglomerating in the gap or clogging the gap. Sleeve 12 and blade 13
The toner 8 that has passed through is charged, is held by the toner conveying body 9 by electrostatic image force, and is conveyed, approaches the development gap (the part where the latent image bearing body 1 and the toner conveying body 9 are close), and is transferred to the supporting part 2. A developing bias applying means 16 applies a voltage between the conductive support 10 and the electrostatic latent image to generate a developing electric field in accordance with the potential contrast of the electrostatic latent image on the latent image carrier 1, thereby causing the charged toner 8 to be latent. The toner 8 attached to the latent image carrier 1 is made to fly toward the electrostatic latent image on the image carrier 1 to obtain an amount of toner adhering according to the potential contrast and visualize the latent image. The toner 8 is electrostatically transferred onto the recording paper 18 and fixed on the recording paper 18 by means such as pressure or heating to obtain a desired image. FIG. 4 shows the relationship between temperature change and developed toner temperature. It can be seen that the developed density does not depend on temperature changes.

In FIG. 1, the potential of each part is set to 1,300V for the conductive support 10, 1,900V for the sleeve 12, and 1,900V for the blade 13, assuming that the support part 2 of the latent image carrier 1 is Ov. The gap between the latent image carrier 1 and the toner conveyor 9
High contrast density gradation when the distance between the toner conveyor 9 and the sleeve 12 is set to 0.2 mm, the distance between the toner conveyor 9 and the sleeve 12 is 0.3 mm, and the distance between the toner conveyor 9 and the blade 13 is 0°15 mm. By using a semiconductor laser as the light source 5, it was possible to form a toner image with high resolution and excellent area gradation.

Further, as the detector 19, various thermometers can be used, including a resistance thermometer such as a thermistor thermometer and a copper resistance thermometer. The position of the detector 19 is not limited to the position shown in FIG.
It may also be arranged outside the developing device. Further, in FIG. 1, the arrows indicate the rotation directions of the respective members, but this does not limit the present invention, and the above-mentioned numerical values also do not limit the present invention. The method of constructing the photosensitive layer is not limited to that shown in this figure.

Comparative Example Image formation was carried out in the same manner as in Example 1, except that the electric field formed between the conductive support 10 and the sleeve 12 was not corrected for temperature changes.

The relationship between the temperature change at that time and the developed toner temperature is shown in the fifth column.
Shown in the figure. It can be seen that as the temperature increases, the developed toner flow rate decreases.

Example 2 Image formation was carried out in the same manner as in Example 1, except that the detector 19 detected changes in humidity and changed the thickness of the electric field applied between the sleeve 12 and the conductive support 10. went.

The density of the developed toner remained constant regardless of changes in humidity.

Further, as the detector 19, various thermometers can be used, including electric (resistance) type humidity sensors such as electrolyte type, organic type, metal and metal oxide type humidity sensors. The position of the detector 19 is not limited to the position shown in FIG. 1, but may be placed near the toner conveying body 9 or the sleeve 12, or outside the developing device.

[Effects of the Invention] As described above, according to the present invention, a conductive support that is disposed adjacent to a latent image carrier that forms an electrostatic latent image and that conveys toner, which is an image forming member, a toner transport body on which an insulating layer is formed; an electrically conductive toner transport amount regulating member is disposed adjacent to the toner transport member; and a conductive toner transport amount regulating member is provided between the conductive support and the toner transport amount regulating member. In the developing device, an electric field is applied by a voltage applying means to cause the toner on the toner conveying member to electrostatically adhere to the latent image carrier to visualize the electrostatic latent image. By changing the electric field between the body and the toner transport amount regulating member in response to changes in the environment such as temperature and humidity, the amount of toner to be developed can be kept constant.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional schematic diagram of a developing device according to an embodiment of the present invention, and FIG. 2 is a relationship between the electric field between the conductive support and the toner transport amount regulating member and the amount of developed toner in the developing device of the present invention. 3 is a diagram showing the relationship between the electric field between the conductive support and the conductive support portion of the latent image carrier in the developing device of the present invention and the amount of developed toner, and FIG. 4 is a diagram showing the relationship between the amount of developed toner and the amount of developed toner FIG. 5 is a diagram showing the relationship between the temperature change and the developed toner concentration in the example, and FIG. 5 is a diagram showing the relationship between the temperature change and the developed toner temperature in the comparative example of the present invention. 1: Latent image carrier 2: Conductive support Photosensitive layer Charger Light source Imaging optical system Developing device Toner Toner transport body Conductive support Insulating layer Sleeve Blade Voltage applying means Scraper Developing bias applying means Transfer device Recording paper detector mouth r) [=] LC) [=] [=] M7) bl) [=] L() [=] bl) [=] [=] Ug) [=] LC) [:)

Claims (3)

[Claims] (1) It has a toner transport body that is disposed adjacent to a latent image carrier that forms an electrostatic latent image and has an insulating layer formed on a conductive support that transports toner, which is an image forming body. , an electrically conductive toner transport amount regulating member is disposed adjacent to the toner transport body, and an electric field is applied between the conductive support body and the toner transport amount regulating member by a voltage applying means, so that the toner transport amount is In a developing device that makes the toner on a conveying body electrostatically adhere to the latent image carrier to visualize the electrostatic latent image, an electric field between the conductive support and the toner conveyance amount regulating member is provided. A developing device characterized in that it changes in response to changes in the environment. (2) The developing device according to claim 1, wherein the environment is a temperature environment. (3) The developing device according to claim 1, wherein the environment is a humidity environment.