JPS63157139A - Device for securing light quantity of fluorescent lamp - Google Patents

Abstract

PURPOSE:To set a tube temperature to a temperature securing the minimum light quantity required for reading an image or above, by monitoring a tube temperature, operating a machine cooling fan at a set temperature or above, and stopping the fan at a set temperature or below. CONSTITUTION:When a main power source switch is turned on, a CPU 1 brings an electric application to a fluorescent lamp 3 to be held during a preheating time T0, and subsequently, checks the rise of a machine temperature caused by turning on the fluorescent lamp 3, by the output of a sensor 5. When the machine temperature does not reach a set temperature, the fluorescent lamp 3 is lightened. This lighting time is monitored, and when t1 elapses, the fluorescent lamp 3 is turned off, and when t1 does not elapse, whether or not a machine temperature T'0 of its time point is the set temperature or above is checked. In such a way, by turning on and off the fluorescent lamp 3 and a fan motor 2 in accordance with a tube temperature, the tube temperature of the fluorescent lamp 3 is controlled without using a heater, and its light quantity is secured.

Description

[Detailed Description of the Invention] (Technical Field) The present invention relates to a light amount guarantee device for fluorescent lamps used in scanners of copying machines, etc., and more specifically, the present invention relates to a light amount guarantee device for fluorescent lamps used in scanners of copying machines, etc. This invention relates to a light amount guarantee device for fluorescent lamps that can maintain the tube temperature at an appropriate temperature.

(Prior Art) Fluorescent lamps have conventionally been used as light sources in scanning mechanisms such as copying machines.

When the tube temperature of this fluorescent lamp is low, such as when the power is turned on, the light intensity is low and it is not possible to read documents, etc., so a heater is generally wrapped around the fluorescent lamp.

When the power is turned on, it is energized and heated.

When the tube temperature reaches a certain temperature due to heating by the heater, the electricity is turned off.

By the way, in general, a copying machine has a temperature rise of 20 to 25 degrees inside the machine.

Fluorescent lamps are heated by the ambient temperature, and a heater is rarely used during use.

Therefore, when the temperature of the heater is low, the main switch is turned off.
The reality is that copying is limited to one time immediately after N, and the usage rate of the heater is extremely low.

〔the purpose〕

The present invention has been made in view of the above, and its purpose is to provide a light amount guarantee device for a fluorescent lamp that can control the temperature of a fluorescent lamp for a reading light source without using a heater. It is.

〔composition〕

To achieve this purpose, the system is configured to monitor the internal temperature of the machine, operate a fan for cooling the machine at a temperature above a set temperature, and stop the fan when the temperature is below the set temperature.

Two embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a layout diagram showing the internal configuration of a copying machine.

Here, an example of application to a digital copy scanner is shown.

In FIG. 1, the control system includes a fan motor 2, a fluorescent lamp 3,
and a CPU 1 and 2 that control the servo motor 4, a fan motor 2 that cools the inside of the machine, and a CPU that is incorporated into the scanner.
A fluorescent lamp 3 illuminates the surface of the document to be read, and a servo motor 4 moves the scanner or the document table.

An in-machine temperature sensor 5 that detects the in-machine temperature which is information used when controlling the fan motor 2; a driver 6 that drives the fan motor 2 based on a control output signal from the CPU 1;
It is comprised of a ballast 7 that drives the fluorescent lamp 3 based on the control output signal of the PUI, and a servo control board 8 that controls the servo motor 4 under the control of the CPUI.

As shown in FIG. 2, the interior of the copying machine includes a contact glass 21 on which a document is placed, a scanner 22 that integrally moves a fluorescent lamp 3 and an optical system on the bottom surface of the contact glass 21, and An image reading section 23 that reads optical information of A fan motor 2 is installed at an appropriate position.

The operation of the above configuration will be explained with reference to the time chart shown in FIG.

When the power switch is turned on, the preset time t0
is measured.

This time t0 is provided because analog copiers, laser printers, etc. require time from turning on the power switch to rising the fixing temperature. This time t0
It is necessary to raise the tube temperature of the fluorescent lamp 3 in the scanner 22 within a certain period of time.

For this purpose, in the past, a heater was provided to perform forced heating.

However, due to the heating of this heater, not only the temperature inside the fluorescent lamp 3 but also the temperature inside the 8g rises, so the fan motor 2
is used to control the increase so that it is 20 to 25 degrees.

As shown in Figure 3, the CPU indicates that 8 hours t0 has elapsed.
1, the CPUI turns on the fluorescent lamp 3 via the ballast 7.

Due to this lighting, the tube temperature of the fluorescent lamp 3 rises rapidly,
Meanwhile, the temperature inside the 9 aircraft gradually rises.

The relationship between the temperature of the fluorescent lamp 3 and the luminous flux is shown in Fig. 2.
The higher the ambient temperature, the more the amount.

Further, the normal value of 1 is reached within several minutes from the start of 9 energization.

Incidentally, FIG. 5 shows the relationship between the tube wall temperature (tube temperature) of the coldest part of the fluorescent lamp 3 and the light output.

It can be seen that the necessary amount of light cannot be obtained below the tube temperature.

From the characteristics shown in FIG. 4, it is possible to know the lighting time t1 corresponding to the ambient temperature detected by the sensor 5.

This tl is determined by the CPU, and the fluorescent lamp 3 is turned on via the ballast 7 until the end of 2 hours t1.

Time 1. This turns off the fluorescent lamp 3 and generates a scanner start-up signal.

Make it known that copies can be made at any time.

Changes in the temperature inside the two machines are monitored by a sensor 5, and when the temperature reaches T shown in Figure 3, the fan motor 2
Rotate to cool the inside of a.

Note that the fan motor 2 is stopped when it is detected that the temperature inside the machine becomes T or less.

Such motor control is repeated thereafter based on the sensor output.

FIG. 6 is a flow chart showing control of the fan motor 2 and fluorescent lamp 3 by the CPU.

When the main power switch is turned on, preheating time T begins. During this time, the fluorescent lamp 3 is energized (step 31).

Next, in step 32, a check is made to see if the temperature inside the machine has increased due to the lighting of the fluorescent lamps 3.

T6 < T l+, that is, when the temperature inside the machine does not reach the set temperature, the fluorescent lamp 3 is immediately energized.

Turn it on.

The lighting time t1 is monitored in step 34, and when tl has elapsed, the fluorescent lamp 3 is turned off.

If 1. does not elapse, the cabin temperature To” at that time
Check whether or not the temperature is higher than the set temperature (step 35).
.

If TO'<TI, the fluorescent lamp 3 continues to be lit until t is reached; if To'>T, the fan motor 36 is turned on (step 36).

The inside of the machine is cooled and the fluorescent lamp 3 is turned off (step 37).

This prevents the tube temperature from rising above the appropriate temperature.

Partly, in step 32, the temperature inside the machine is 9.

If To>Tr, the tube temperature exceeds the appropriate temperature value even if the fluorescent lamp 3 is OFF, so the fan motor 2 is turned ON to lower the temperature inside the machine in step 39)9.

Since the tube temperature of the fluorescent lamp 3 is such that sufficient luminous flux can be obtained for image reading in the steps leading up to step 37 and step 39, the scanner 22 is set to be ready for operation at any time (step 3). ).

Therefore, reading is started by pressing the copy start button.

By turning on and off the fluorescent lamp 3 and fan motor 2 according to the tube temperature as described above.

The tube temperature of the fluorescent lamp 3 can be controlled without using a heater, and the amount of light of the fluorescent lamp 3 can be guaranteed.

〔effect〕

As explained above, according to the light amount guarantee device for a fluorescent lamp according to the present invention, the temperature inside the device is monitored.

Operate the fan for cooling the inside of the machine above the set temperature.

Since the fan is controlled to stop when the temperature is below the set temperature, the tube temperature of the fluorescent lamp can be controlled without using a heater, and the tube temperature can be kept above the temperature that guarantees the minimum amount of light necessary for reading images. can do.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a diagram showing the internal configuration of a copying machine to which the present invention is applied.
Fig. 3 is a time chart explaining the present invention in detail, Fig. 4 is a characteristic diagram showing the relationship between the tube temperature of the fluorescent lamp and the luminous flux, and Fig. 5 is the temperature of the tube wall of the coldest part of the fluorescent lamp. and. FIG. 6 is a characteristic diagram showing the relationship between optical outputs, and FIG. 6 is a flowchart showing control in the present invention. Explanation of symbols 1...CPU, 2...Fan motor 3...Fluorescent lamp, 4...Servo motor 5...In-machine temperature sensor. 6... Driver, 7... Ballast 22... Scanner, 23... Image reading section 25... Power supply section

Claims (1)

[Claims] A fluorescent lamp used in a scanner of a copying machine, etc. includes a temperature detection means for detecting the temperature of an atmosphere in which the fluorescent light is installed, and a temperature detected by the temperature detection means is below a set value. control means for turning on the fluorescent lamp and extinguishing it when the fluorescent lamp exceeds a set value, and extinguishing the fluorescent lamp after a certain period of time when the set value is not reached;
A light amount guarantee device for a fluorescent lamp, characterized in that the tube temperature of the fluorescent lamp is set to a temperature higher than a required temperature.