JPS626277A - Exposing device - Google Patents

Abstract

PURPOSE:To obtain a quantity of light enough for proper exposure even right after warming-up operation by allowing a ready display means to make a ready display when the quantity of light of a fluorescent lamp or light quantity equivalent value and the temperature of a fixing roller reach specific values respectively during the warming-up operation. CONSTITUTION:A ready lamp turn-on control circuit 33 is applied with the output of a light quantity detection sensor 31 and the output of a temperature detection sensor 32 and powers on the ready lamp 34 on knowing the outputs of both sensors 31 and 32 exceed their stored reference values to illuminate, indicating that copying operation is possible. When a copy button is pressed, a fluorescent lamp turn-on control circuit 32 begins to feed electricity to the fluorescent lamp 20 to perform the copying operation.

Description

[Detailed description of the invention] t fill1 day n) iffi m f%
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure device used in an image forming apparatus that uses a fluorescent lamp as an exposure light source.

(Prior Art) An electronic copying machine exposes a charged drum to light in accordance with document information, and then forms a toner visible image on an electrostatic latent image formed on the drum surface. This is a device that transfers images onto copy paper.

No. 28 is a diagram showing an example of the conventional configuration of such an electronic copying machine. When the operator presses a copy start button (not shown), the illustrated device begins a copy operation. After the remaining toner on the photosensitive drum 1 is scraped off by a blade in the cleaning section 2 and the photosensitive drum 1 is rotating in the direction of the arrow, it is corona discharged by the charged electrode 3 and the electric charge of the seedlings is applied to the entire surface of the photosensitive drum 1. Becomes electrically charged. An unnecessary portion of the charge charged by the charging electrode 3 is erased by a charge eraser 4.

On the other hand, 11 which is on/off controlled by the fluorescent lamp lighting circuit 5
Kibe Rhs Rake Hara Ayao 7 "Light is irradiated on Hoko Wakaroku Reka Hara 8, and the reflected light is focused by Selfoc lens (manufactured by Nippon Sheet Glass Co., Ltd.) 9, which is an example of a light transmission body. and irradiates the photosensitive drum 1.

Here, when the document table 7 is horizontally moved in the direction of the arrow in the figure,
Image information on the original 8 is focused by a SELFOC lens 9 and sequentially irradiated onto the photosensitive drum 1.

As a result, the unnecessary portion (area corresponding to the non-image portion) is charged and erased by the charge erasing unit 4, and an electrostatic latent image of the document image information is sequentially formed on the charged region of the photosensitive drum surface where an image is to be formed. Ru. The electrostatic latent image formed on the surface of the photosensitive drum 1 is converted into a visible image by adsorption of toner in the subsequent developing section 10. The toner image on the surface of the photosensitive drum is transferred to a copy paper in a transfer section 11, and the copy paper that is in close contact with the photosensitive drum 1 is separated. The separated copy paper is sent to the fixing roller 13 via the conveyance mechanism 12, and the copy paper is heated and pressurized by the fixing roller 13 to fuse the toner on the copy paper to the copy paper, and the copying operation is completed. finish.

Incidentally, as the light source 20 used in the exposure section 6, a fluorescent lamp as shown in FIG. 3 may be used. Third
In the figures, (a) is a perspective view, and (b) is a sectional view taken along the line AA'. In the figure, 21 is a pin, 22 is a cap, 2
3 is a heater formed surrounding the fluorescent tube 24; 25 is a heat generating portion of the heater 23; The heat generating part 25 is 1, for example (
Fluorescence as shown in b)! ! Pasted around 24,
Furthermore, it may be fixed with a heat shrink tube (not shown) or the like from above. Alternatively, there are cases where the tube is simply attached to the surface of the fluorescent tube without using a heat shrink tube. 26
．． 27 is an electrode for applying current to the heater 23; 28
29 is a reflective film/fluorescent film, and 29 is an aperture portion. The heater 23 is the II of the fluorescent tube 24! ! It is designed to quickly increase the water level.

I! of a fluorescent lamp configured in this way! The relationship between the wall temperature and the amount of emitted light is shown in FIG. 4. In the figure, the horizontal axis shows the fluorescent lamp tube wall temperature, and the vertical axis shows the amount of emitted light.

If the tube wall temperature of the fluorescent lamp does not reach a predetermined reference value (jo in the figure) within the warm-up time of the fixing heater provided in the fixing roller 13, the amount of light will be insufficient. The amount of light emitted at temperature to is Lo, and if the tube wall temperature of the fluorescent lamp does not exceed to within the warm-up time, the amount of light will be LO.
As a result, the amount of light becomes insufficient and accurate copying of images becomes impossible.

(Problems to be Solved by the Invention) However, in the conventional apparatus, when the temperature of the fixing heater reaches a predetermined reference value during warm-up after the power is turned on, it is assumed that the warm-up is completed and copying is possible. For this reason, if the ambient temperature of the fluorescent lamp is low and the fluorescent lamp tube wall temperature is low when the power is turned on, the fluorescent lamp tube wall temperature will not reach the specified value even if the fuser heater temperature has reached the specified reference value. If it is lower than the reference value to, the light amount will be less than Lo, and proper exposure may not be possible.

The present invention has been made in view of these points, and
The purpose of this is to obtain the amount of light necessary for proper exposure even immediately after warm-up is completed (means for solving the problem). The reflected light or the light based on the reflected light is irradiated onto the photoreceptor to generate static electricity? An exposure device used in an image forming apparatus that forms an iI image, develops the electrostatic latent image, adsorbs toner on a copy paper, and fixes it as an image through a fixing roller, and the exposure device A light amount and light amount equivalent value detection sensor to detect, a temperature detection sensor that detects the temperature of the fixing roller, and a ready display means control that controls the ready display means based on the outputs of the light amount and light amount equivalent value detection sensor and the temperature detection sensor. comprising a circuit;
The present invention is characterized in that when the light amount of the fluorescent lamp, the light amount equivalent value, and the temperature of the fixing roller each reach a certain value during warm-up, a ready display is performed by the ready display means.

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Figure 1 is a block diagram showing one embodiment of the present invention, and the same parts as in Figure 2 are designated by the same numbers.

In the figure, 31 is a light amount detection sensor that is an example of a light amount equivalent value detection sensor that detects the amount of light emitted from the fluorescent lamp 2o;
32 is a temperature detection sensor that detects the temperature of the fixing roller 13; 33 is the light amount detection sensor 31 and the temperature detection sensor 32;
Ready lamp 34 which is a ready display means receives the output of
This is a ready lamp lighting control circuit that performs on/off control of energization.

The ready lamp lighting control circuit 33 stores in advance a reference value for the amount of light necessary for proper exposure and a reference value for the temperature at which fixing is possible, and when the amount of light and temperature reach the respective reference values, the ready lamp 34 is turned on. A ready display is performed by turning on the power and lighting the ready lamp. The operation of the device configured as described above will be explained as follows.

When you turn on the electronic copying machine, first the fixing roller 13
The fixing heater (not shown), the fluorescent lamp 20, and the fluorescent lamp heater 23 (see FIG. 3) are energized. As a result, the tube wall of the fluorescent lamp generates self-heating due to energization and the heater 2
Due to the heat generated from the heat generating part 25 by energizing 3,
gradually rises. As the temperature of the tube wall increases, the amount of light emitted from the fluorescent tube through the aperture section 29 increases accordingly, as shown in FIG. The output of the light amount detection sensor 31 and the output of the temperature detection sensor 32 are added to the ready lamp lighting control circuit 33.

When the ready lamp lighting control circuit 33 learns that the output of the light amount detection sensor 31 and the output of the temperature detection sensor 32 exceed the respective stored reference values, it energizes the ready lamp 34. lady lamp 3
4 lights up to notify the operator that copying is now possible. When the operator presses the copy button, the fluorescent lamp lighting control circuit 32 starts energizing the fluorescent lamp 20 again, and performs the copying operation in the manner described with reference to FIG.

Note that during the copying operation, the amount of light emitted from the fluorescent lamp 20 is controlled to be constant. Once the power supply to the fluorescent lamp 20 is stopped, the temperature of the wall of the fluorescent lamp tube hardly decreases, and it reaches about
is maintained. Therefore, when the operator presses the copy button and energization of the fluorescent lamp 20 is started, the amount of emitted light quickly reaches the reference value Lo, providing a sufficient amount of light.

As described above, according to the present invention, the ready lamp is turned on when the light intensity of the fluorescent lamp reaches the light intensity necessary for proper exposure and the temperature of the fixing heater reaches a temperature that allows fixing, and when warm-up is completed. As a result, high-quality copies can be made with appropriate exposure even when copying immediately after warm-up is completed.

Furthermore, in the above explanation, the case where the fluorescent lamp is always on during warm-up was explained as an example, but if the light intensity of the fluorescent lamp exceeds the reference value Lo, the power supply to the fluorescent lamp may be stopped, or the fluorescent lamp may be turned off. When the wall temperature reaches a certain value (for example, jo>), the power supply may be stopped. By stopping the power supply to the fluorescent lamp in this way, the lighting time of the fluorescent light when the fixing roller is warmed up can be shortened. The lifespan of fluorescent lamps can be significantly extended.For example, if the ambient temperature of fluorescent lamps is high (close to jn in the Chiku4 diagram), there is almost no need to turn on the fluorescent lamps, reducing power consumption. The amount can also be kept low.

Further, in the above explanation, the case where the light intensity of a fluorescent lamp is detected as a reference value is explained as an example, but the present invention is not limited to this, and the case where the tube wall temperature is detected as a predetermined value corresponding to the reference light intensity is explained. A value may be set and detection may be made when this predetermined value is reached.

Alternatively, it may be possible to detect when the time during which the fluorescent lamp is energized exceeds the time corresponding to the reference light amount value LO. Incidentally, although the above embodiment described a conventional copying machine,
Of course, the present invention can be applied to copying machines that use laser optical systems. Further, although the ready display is performed using a ready lamp, it goes without saying that it may also be performed using a voice.

(Effects of the Invention) As described above in detail, it is possible to realize an exposure apparatus that can obtain the amount of light necessary for proper exposure even immediately after warm-up is completed.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a diagram showing an example of the conventional structure of an electronic copying machine, Fig. 3 is a diagram showing an example of the structure of a fluorescent lamp, and Fig. 4 is a diagram showing an example of the structure of a fluorescent lamp. FIG. 3 is a diagram showing light emission characteristics. 1... Photosensitive drum 2... Cleaning section 3.
... Charged electrode 4 ... Charge erasing section 5 ... Fluorescent lamp lighting circuit 6 ... Exposure section 7 ... Original table
8... Original 9... SELFOC lens 10... Developing section 11... Transfer section 12...
Conveyance mechanism 13...Fixing roller 20...Fluorescent lamp 31...Light amount detection sensor 32...Temperature detection sensor 33...Ready lamp lighting control circuit 34...Ready lamp patent applicant Roku Konishi Photo Industry Co., Ltd. Agent Patent attorney Fuji Ijima 1 person Figure 3 (b) tOno light tube wall swamp

Claims (1)

[Claims] Irradiating the document surface with a fluorescent lamp and irradiating the photoreceptor with reflected light or light based on the reflected light to form an electrostatic latent image,
An exposure device used in an image forming apparatus that develops the electrostatic latent image, adsorbs the toner onto copy paper, and fixes it as an image through a fixing roller, which detects the light amount or light amount equivalent value of a fluorescent lamp. a value detection sensor, a temperature detection sensor that detects the temperature of the fixing roller, and a ready display means control circuit that controls the ready display means based on the outputs of the light amount, light amount equivalent value detection sensor, and temperature detection sensor, When the light intensity of the fluorescent lamp, the light intensity equivalent value, and the temperature of the fixing roller each reach a certain value during warm-up,
1. An exposure apparatus characterized in that a ready display is performed by a ready display means.