JPS63246756A - Copying machine - Google Patents

Abstract

PURPOSE:To shorten the waiting time after supply of a power source by providing a photodetector for detecting the quantity of light of a florescent lamp and outputting a copiable signal when said detector detects that the quantity of the light of the fluorescent lamp attains a min. required limit after supply of the power source. CONSTITUTION:The photodetector 30 which detects the quantity of the light of the fluorescent lamp 3 is provided and is so constituted that the quantity of the light of the fluorescent lamp 3 is detected by this photodetector 30 after supply of the power source and the copiable signal is outputted when the detector detects that the quantity of the light attains the min. required limit. More specifically, the quantity of the light attaining the min. required limit can be directly detected and the copiable signal emitted when the quantity of the light of the fluorescent lamp 3 attains said limit after supply of the power source. Copying is, therefore, permitted immediately when the min. quantity of the light necessary for copying a pale original having many white paper parts is attained. The waiting time after supply of the power source is thus shortened in the case of copying such original.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a copying machine, and particularly to a copying machine using a fluorescent lamp as an exposure illumination device.

(Prior art) In a copying machine that uses a fluorescent lamp as an exposure illumination device,
Since the amount of light of a fluorescent lamp has a temperature characteristic that changes depending on the temperature of the tube wall, the startup time after turning on the power also changes depending on the temperature. Therefore, in the past, temperature detection was used to detect the rise time until the fluorescent lamp reaches a light intensity that allows copying after the power is turned on.

For example, in Japanese Unexamined Patent Publication No. 58-105225, when the power is turned on, a heater that heats the fluorescent lamp and its tube wall is turned on, and the tube wall temperature of the fluorescent lamp is detected, and a light amount that allows the tube wall temperature to be copied is obtained. The device is configured to output a copy enable signal when the reference temperature is reached, and thereafter continue heating by the heater until the temperature reaches the temperature control range.

(Problem to be Solved by the Invention) By the way, in the above-mentioned MItr&, when the power is turned on, the fluorescent lamp is turned on together with the heater, and the temperature of the tube wall of the fluorescent lamp is quickly raised, making it possible to make copies in the darkness for a short time. However, since the temperature of the tube wall of the fluorescent light is detected to determine whether the fluorescent light has reached a predetermined amount of light that allows copying, a temperature detector is installed on the tube wall of the fluorescent light. In addition, it is not possible to accurately recognize the actual amount of light, and therefore, in order to prevent defective copies from occurring due to insufficient light amount, it is necessary to set strict conditions for issuing the copy enable signal. As a result, there was a problem in that it took a long time to wait after the power was turned on.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, it is an object of the present invention to provide a copying machine that can output a copy ready signal as soon as the fluorescent lamp reaches the minimum necessary light intensity and has a short waiting time after power is turned on.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a photodetector for detecting the amount of light from the fluorescent lamp in a copying machine equipped with a fluorescent lamp as an exposure illumination device. The present invention is characterized in that the photodetector detects the amount of light from the lamp and outputs a copy enable signal when it is detected that the amount of light has reached the minimum required level.

(Function) Since the present invention has the above-mentioned configuration, when the fluorescent lamp reaches the minimum amount of light required to enable copying after the power is turned on, it can be directly detected by the photodetector and a copyable signal can be emitted. Since copying is possible as soon as the minimum amount of light necessary for copying a pale am with many blank parts is reached, the waiting time after power is turned on can be shortened when copying such an original.

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 6.

Figures tj & 5 show the overall configuration of the copying machine, where 1 is the original platen, 2
5 is a first movable table as a scanner equipped with a fluorescent lamp 3 as an exposure light source and a first mirror 4; 5 is a second and third mirror 6;
．． Scanning is performed by the first moving table 2 moving along the lower surface of the document table 1, and the fjS2 moving table 5 is interlocking with the movement of the tIS1 moving table 2. By moving by one-half of that length, the optical path length is kept constant even when scanning.

8 is a through lens, 9 is a fourth mirror, and 10 is a photoreceptor, which is configured to project the image on the document table 1 onto the photoreceptor 10. A developing device 11, a transfer charger 12, a cleaner 13, and a charging charger 14 are arranged around the photoreceptor 10.

Further, 15 is a paper feeding section, 16 is a registration roller, 17 is a fixing section, and 18 is a discharge roller.

FIG. 4 shows a control block diagram of the copying machine, in which 21 is the main body control part 1, the main switch 22, the print switch 23
and other input systems 26, and the optical system 124, P2O circuit 25, and other output systems 27 are controlled according to a predetermined program. Further, in order to control exposure by the fluorescent lamp 3, a photosensor 30 for detecting the light of the fluorescent lamp 3 is provided, and its detection signal is input to a fluorescent lamp control section 31 that controls the fluorescent lamp 3, and It is configured to input and output signals between the main body control section 21 and this fluorescent lamp control section 31.

The fluorescent lamp control section 31 is configured as shown in FIG. That is, based on a command from the main body control unit 21, the microcomputer 32 changes the relative ratio (duty) between the energizing time and the stopping time of the high frequency wave applied from the lighting circuit 33 to the fluorescent lamp 3, and performs dimming. . Further, the light output of the fluorescent lamp 3 is detected by the optical sensor 30, converted to voltage by the photoelectric conversion circuit 34, A/D converted by the microcomputer 32, and the light amount is determined by the main body control section 21.
It is configured to provide feedback to

Further, in the operation section of the copying machine shown in FIG. 1, 41 is a print key, 42 is an interrupt key, 43 is a copy number setting up key, 44 is a copy ready display section, 45 is a jam display section, 4
Reference numeral 6 designates a set number of sheets display unit, 47a to 47c display allowable copy density display units that each display that the allowable copy density has reached 1.3.5, and 48 represents an exposure volume.

Showing the rise characteristics of light intensity after power-on! @ In Figure 2, the light f! on the vertical axis! k11 is the light amount corresponding to the above-mentioned copyable density 1, and similarly 13.1. are the density corresponding to the copyable density 3.5, respectively, and tl and t3.1 on the horizontal axis
．． respectively indicate the time it takes to reach the corresponding light amount after the power is turned on, and the time it takes to reach the light amount 1 is significantly shorter than the time it takes to reach the light amount l.

Next, the operation of the copying machine having the above configuration will be described at 70 in FIG.
- Explain the operation based on the chart.

First, the main switch 22 is turned on at step well 1,
When the power is turned on, in step #2, the fluorescent lamp 3 is fully lit (lit with the duty set to 100%). In step #3, this light amount is detected by the optical sensor 30 and fed back, and in step #4, the light amount is determined.

Here, a state method is adopted, and the initial value of the state is set to 0. The image density of 1.3.5 in step #5.9.12 corresponds to setting the copyable density display to these three levels in this embodiment. Then, the original density is light in the order of image density 1.3.5,
Standard and dark mean that the corresponding target light amounts increase in the order of 1.3.5.

In step #4, if state = 0, step #4
5, it is determined whether the image density has reached 1 (reference 11 in FIG. 2), and if it has not reached it, the process returns to step #3 with the state unchanged. If the target light amount reaches 11 in step #5, the state is increased by 1 in step #6, and the first
Displayed on the copyable display section 44 in the figure, step #
At step 8, the copyable density display section 47a displays the copyable density 1 in FIG. 1, and the copyable state is set. Also, if the state is 1 or 2 in step #4, the same process is performed and the process moves to step #14.

In step #14, it is determined whether or not the print switch 23 has been pressed, and if it has not been pressed, step #3
Return to and continue the process above.

If the print switch 23 is pressed in step #14, the process moves to the next step #15, where the exposure volume 48 is inputted, the duty is calculated so that the amount of light corresponding to the volume value is obtained, and the process proceeds to step #16. It is determined whether the input value of the exposure volume 48 is below the copyable density.

Here, if the density is below the allowable copying density, proceed to the next step #1.
Moving on to the copy control in step 7, the paper feed system, optical system, P/C circuit,
Processing such as paper ejection is performed, and the copying of one sheet is completed.

As described above, according to the present invention, as soon as the light amount reaches a level that allows copying with an image density of 1, copying becomes possible.As shown in FIG. There is no need to wait at a t, insect, and the waiting time can be significantly shortened.

In the present invention, a heater for auxiliary heating or heat retention of the fluorescent lamp may or may not be provided.

(Effects of the Invention) According to the copying machine of the present invention, when the fluorescent lamp reaches the minimum amount of light necessary for copying after the power is turned on, the photodetector can directly detect it and issue a copy ready signal. Therefore, copying is possible as soon as the minimum amount of light necessary to copy a pale original with many blank pages is reached, which reduces the waiting time after turning on the power when copying such an original. Effects can be obtained.

[Brief explanation of the drawing]

Figures 1 to 6 show an embodiment of the present invention. Figure 1 is a plan view of the operation section of a copying machine, Figure 2 is a characteristic diagram of the rise in light intensity after power is turned on, and Figure 3 is a fluorescent light intensity diagram. FIG. 4 is a block diagram of the light control section, FIG. 4 is a control block diagram of the copying machine, FIG. 5 is a schematic configuration diagram of the copying machine, and FIG. 6 is a 70-chart of control. 3...Fluorescent lamp 30......Light sensor 44...Copyable display department Agent Patent attorney Masaru Ishihara Figure 1

Claims (1)

[Claims] (1) In a copying machine equipped with a fluorescent lamp as an exposure lighting device, a photodetector is installed to detect the amount of light from the fluorescent lamp, and after the power is turned on, the photodetector detects the amount of light from the fluorescent lamp to ensure that the amount of light is at the minimum required level. 1. A copying machine characterized in that the copying machine is configured to output a copy enable signal when it detects that the copying machine has arrived at the copying machine.