JPS63206779A - Image forming device - Google Patents

Abstract

PURPOSE:To satisfactorily control quantity of light by turning a light control means to control the irradiation quantity to an original. CONSTITUTION:Light is projected from a fluorescent lamp 26 to the original G set on an original tray 2. A near parabolic light transmission body 27 is provided in the reflected light path from the original G and the reflected light is imaged through the near parabolic light transmission body 27 onto a photosensitive drum 13. A filter 29 as the semicircular light control means along the curved surface of the fluorescent lamp 26 is freely rotatably disposed to face said lamp. The filter 29 has light transmittability and is provided with 1st-4th density parts 29a-29d. A shaft 39 is connected to one end of the filter 29 and an operating knob 31 is equipped thereto. The transmitted light of the stepwise densities corresponding to the 1st-4th density parts 29a-29d is fed to the photosensitive drum 13 by the rotating operation of said knob 31.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Field of Industrial Application) The present invention relates to an image forming apparatus commonly used as, for example, an electronic copying machine.

(Prior art) A light source irradiates a document set on an electronic copy mFi document table, and the reflected light is guided onto a photosensitive drum to form an electrostatic latent image, and this electrostatic latent image is developed. It is supposed to develop through marriage.

By the way, since the amount of light irradiated to j[ mentioned above affects the image quality, it is necessary to adjust it appropriately.

(Problems to be Solved by the Invention) However, in the past, the amount of light was adjusted by controlling the voltage of the light source, which made it difficult to control, especially when a fluorescent lamp was used as the light source. I often had the problem that the amount of light suddenly decreased and could not be adjusted properly.

[Configuration of the Invention (Means for Solving the Problems)] In order to solve the above-mentioned problems, the present invention includes an apparatus main body, a light source provided in the apparatus main body for scanning a document with light, and a light source for scanning a document with light. a dimming means that is rotatably provided to face each other and that changes the light transmittance stepwise along the rotational direction; and an operating section that is provided on the outside of the apparatus main body and that rotates the dimming means. It is characterized by comprising the following.

(Function) With the above means, it is possible to mechanically adjust the amount of light to the document, and furthermore, this operation can be performed from outside the main body of the apparatus.

(Example) The present invention will be described below with reference to an example shown in the drawings. Figure g3 shows the external appearance of the electronic copying machine.
This is the main body of the device. On the top of this device main body 1 is a document table 2.
is provided so as to be movable in the direction of the arrow.

Further, a control panel 3 is provided on the front side of the device main body 1. This control panel 3 has a coffee tongue 4. 177/s), f key 5. Step up key 6, step down key 2. and a display section 10 are provided.

Further, a paper feed tray 11 is provided on one side of the apparatus main body 1, and a paper discharge tray 12 is provided on the other side.

As shown in FIG. 4, a photosensitive drum 13 as an image carrier is rotatably provided approximately at the center of the apparatus main body 1. As shown in FIG. The photosensitive drum 13 is formed by coating an organic photoconductor (OPC) on the outer peripheral surface of an aluminum tube.

A charger 14, an optical system 15. Developing device 16° Transfer peeling device 17
and a cleaning device 18 are arranged in this order.

In addition, the paper feed tray 1 is provided on the lower side of the apparatus main body 1.
A conveyance path 19 is provided for conveying the paper fed from 1. This conveyance path 19 includes a paper feed loaf 20 along the paper conveyance direction. Feed roller 21 凰, registration row 221
b, the transfer peeling device 11, the guide 23 and the fixing device 24;
are arranged in sequence.

Next, the optical system 15 will be explained in detail based on FIGS. 1 and 2. In the figure, reference numeral 26 denotes a fluorescent lamp as a light source, and the iMG set on the document table 2 is irradiated with light from this fluorescent lamp 26.

Further, a convergent light transmitter 27 is provided in the optical path of reflection from the document G, so that the reflected light from the document G is imaged on the photosensitive drum 13 via the convergent light transmitter 27. It has become.

Further, a semicircular filter 29 as a dimming means that follows the curved surface of the fluorescent lamp 26 is rotatably opposed to the fluorescent lamp 26. This filter 29 has a light-transmitting property and is provided with first to fourth density portions 291 to 29d in stages along the direction of rotation. The first to fourth concentration portions 29m to 29d are the first concentration portion 2! i a ill has the highest concentration, the fourth
The density gradually decreases toward the density portion 29d.

The filter 29 is rotatably supported by a support mechanism (not shown), and a shaft 30 is connected to one end thereof. This shaft jO protrudes from the front surface of the apparatus main body 1, and an operating device 31 is installed on this protrusion. By rotating the operating device 31, the filter 29 is
is rotated so that its first to fourth density portions JJa-214 are selectively opposed to the fluorescent lamp 26.

Note that the light from the fluorescent lamp 26 is reflected by the reflector 32 provided on the back side of the fluorescent lamp 26 at 32, and this reflected light passes through the static elimination filter 34 provided in the slit 33 of the frame 28. The above photosensitive drum JJK
It is designed to be irradiated and eliminate static electricity.

Therefore, when copying, first set the original G on the original platen 2 and set the paper P in the paper feed cassette 11, and then turn on the copy switch 4. This)
, the iMG is irradiated with light from the fluorescent lamp 26, and the original G is run, and the photosensitive drum 1 is charged by the charger 14.
The surface of 3 is uniformly charged. ? The reflected light from the document G forms an image on the charged surface of the photosensitive drum 13 via the convergent light transmitter 27, forming an electrostatic latent image. This electrostatic latent image is sent to a developing device 16 by the rotation of the photosensitive drum 130, and is developed with toner supplied from the developing device 16. Then, this toner image is transferred by the action of the transfer charger 17 to the paper P fed from the paper feed tray 11 and sent between the photosensitive drum 13 and the transfer charger 17. After this paper P is peeled off from the photosensitive drum 13, it is sent to the fixing device 24 via the guide 23, and here.

After the image is fixed, the paper is discharged to the paper discharge tray 12.

Incidentally, the quality of the image formed in this manner is affected by the amount of light irradiated from the fluorescent rung 26.

Next, a case in which the amount of light irradiated onto the document G is adjusted will be described.

First, when reducing the amount of irradiated light, rotate the operating device 31 clockwise to adjust the first or second position of the filter 29.
The density portions 29m and 29b are made to face the fluorescent lamp 26 to reduce the amount of transmitted light.

In addition, when increasing the amount of irradiated light, the operating device 31 is rotated counterclockwise to make the third or fourth ruggedness portions 29e and 29tl of the filter 29 face the fluorescent lamp 26, so that the transmitted light i is increase

As mentioned above, by rotating the filter 29, the original M
In order to adjust the amount of light irradiated to the IG, it is possible to reliably adjust the amount of light in one step without flickering or rapidly reducing the amount of light, which is the case when adjusting the amount of light from a fluorescent lamp electrically using voltage control. .

Further, an operating device 31 is provided outside the device main body 1.

Since the filter 29 is rotated by operating the operating device 31, the filter 29 can be operated from outside the apparatus main body 1, which improves work efficiency.

[Effects of the Invention] As explained above, according to the present invention, since the irradiation cover for the original is adjusted by rotating the light control means, the amount of light is adjusted mechanically, which eliminates the need for electricity as in the past. Unlike regular adjustments, the light source does not flicker or the light intensity decreases rapidly, allowing for good adjustment.

Further, the light control means can be rotated from outside the main body of the device using the operating section, which provides an effect of excellent operability.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a sectional view showing an optical system, FIG. 2 is a perspective view showing a light control means, FIG. 3 is a perspective view showing an electronic copying machine, and FIG. The figure shows its internal configuration. 25... Fluorescent lamp (light source), 29... Filter <a1
41 means), G...manuscript, 31...operation device (N part). Figure 1 Figure 2

Claims (1)

[Claims] An apparatus main body, a light source provided within the apparatus main body that scans the document with light, and a dimming device that is rotatably provided opposite the light source and that changes the light transmittance stepwise along the direction of rotation. An image forming apparatus comprising: a means for rotating the light control means; and an operation section provided on an outer side of the apparatus main body for rotating the light adjustment means.