JPS58223295A - Digital lamp regulator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a digital lamp regulator using a microcomputer, and more particularly to a digital lamp regulator suitable for adjusting exposure of a copying machine.

Exposure adjustment means in copying machines and the like used to be mostly analog systems, but they have been avoided due to the complexity of the circuit configuration, the effects of temperature drift, and the difficulty of changing light control settings.Recently, microcomputers ( The digital method has become mainstream due to the fact that it can be easily used (hereinafter referred to as ■■).

However, conventional digital lamp regulators of this type use an MPU to control the phase of the commercial power supply applied to the exposure lamp, so the processing is complicated and requires a large amount of memory capacity. There was a problem that most of the processing in the MPU was taken up by light control processing, making it impossible to perform other processing.

An object of the present invention is to provide a digital lamp regulator that simplifies processing in an MPU, can perform dimming control with high precision, and can process many functions such as a self-diagnosis function with a single-chip MPU. do.

In order to achieve this object, the present invention uses a high frequency power source as a power source for the lamp, and operates it at a certain duty ratio.
By performing FF, dimming control is performed, and the duty frequency and duty ratio f:, MPU
〇An embodiment of the present invention will be described below with reference to the drawings.〇 Fig. 1 shows a digital clock according to an embodiment of the present invention. This is a schematic diagram of the lamp regulator, in which 1 is a fluorescent lamp, 2 is an optical fiber, 3 is a light receiver, 4 is an integrator, 5 is a converter, 6 is a dimming setting device, 7 is an MPU, and 8 is a light receiver. Power supply stabilizer, 9 is ■ light value display, 10 is self-diagnosis result display, 11
is an external clock generator.

FIG. 2 shows a built-in functional block diagram of the MPU 7, in which 71 is a dimming setting value calculation section, 72 is an S/P (serial roots 4 parallel) conversion section, 73 is a comparison section, and 74 is a duty ratio. A calculation section 75 is a counter section, 76 is a chop signal generation section, and 77 is a self-diagnosis section.

With the following configuration, the amount of light from fluorescent rung 1 can be changed to optical fiber 2.
The signal is taken out to the photoreceiver 3 via the radiator 3, converted into an electric signal, and then applied to the integrator 4. As a result, the integrator 4 outputs a DC analog signal proportional to the amount of light from the fluorescent rung 1. Further, this analog signal is converted into a digital signal a by a gauze converter 5, and is serially applied to the MPU 7. On the other hand, the MPU 7 also receives a dimmer signal from the dimmer setting device 6 for increasing or decreasing the amount of light from the fluorescent run f1.

As a result, the dimming setting value calculation unit 71 of the MPU 7 sets the light intensity of the fluorescent rung 1 in 10 steps from O to 9 according to the dimming signal from the dimming setting device 6. is calculated and displayed on the dimming value display 9, and the corresponding digital setting value is output to the comparison section 73. On the other hand, the S/P conversion section 72 receives the output of the converter 5, converts it into parallel data, and outputs it to the comparison section 73 and self-diagnosis section 77. By monitoring this data, the self-diagnosis section 77 determines the lifespan of the fluorescent pump 1, abnormal lighting, etc., and displays the self-diagnosis results on the self-diagnosis result display 10. The setting value from the setting value calculation unit 71 and the S
It compares the light quantity value of fluorescent rung 1 from the /P converter 72 and outputs the deviation value to the duty ratio calculator 74. Further, the duty ratio calculation unit 74 increases or decreases the duty ratio according to the deviation value, and sends the calculated duty ratio to the counter unit 75 at regular timings! Reset. The counter section 75 adds the external clock C input from the external clock generator 11 to its preset value and counts it, and outputs an overflow signal to the chop signal generation section 76 . The chop signal generating section 76 inverts the signal state each time this signal is output, and returns the signal state to the original state at each of the above-mentioned fixed timings, thereby generating a chop signal (hereinafter referred to as signalable) d. .

In this way, for example, l k output from the MPU 7
In response to the PWM signal d of Hz, the power supply stabilizer 8 generates a high frequency current (50 k) Iz, for example, applied to the fluorescent rung 1.
) ef＼As shown in FIG. 3, change the light intensity of ON-OFF L and fluorescent rung 1. As described above, this light amount change is fed back to the MPU 7, and as a result, the comparison unit 73
As a result of the comparison, if the light intensity of fluorescent rung 1 matches the set light intensity, there will be no output to the duty ratio calculation unit 74, and from then on, a constant duty ratio will be output from the duty ratio calculation unit 74 at a constant timing. It is output and set in the color/printing section 75.

FIG. 3 shows a specific configuration diagram of the digital lamp regulator outlined above, and parts corresponding to those in FIG. 1 are given the same reference numerals.

In the figure, SW1 is a contact piece that turns the fluorescent rung 1 ON-OFF. SW2 and SW3 are push-button switches for setting the dimming in 10 steps.The dimming setting value is incremented by 1 when the switch SW2 is pressed, and is decremented by 1 when the switch SW3 is pressed. That is,
MPII 7 detects the input from switches SW2 and SW3 by mis-scanning ports P25 and P2O'i, increases or decreases the dimming setting value, and sends it to port PIO'i.
~ P13 is used to output (6) to the decoder 12 in 4 bits, and the dimming setting value is set by looking at the 7-segment dimming position display 9. At this time, the switch of the dimming setting device 6 is By continuing to press SW3 and SW4, port P25 is set to warn the operator when attempting to set the set value lower than 0 or higher than 9.
A caution signal is outputted, and a flash drive 13 or a caution lamp 14 is activated. Further, the warning rung 13 and the caution rung 14 are also activated when the display state of the dimming position indicator 9 is changed. On the other hand, as mentioned above, MPU7
Self-diagnosis information is output and displayed on the self-diagnosis result display 10, and this information is also output using ports P10 to P13. That is, the MPU 7 alternately outputs the output from the PIO-PI 3 to the dimming position display 9 and the output to the self-diagnosis result display 10, and at the same time synchronizes with the output, outputs the N
-) By turning PIO 0N-OFF, each dry) 4
-15 and 16 are alternately driven, dynamic lighting of the dimming level display 9 and the self-diagnosis result display 10 is performed.

In this embodiment, the MPU 7 is configured using an 8749, and the A/D converter 5 is configured using a 4052.

8749tj: Internal program memory for 2, 128
6D, 405 MPU with byte data memory, 2 input/output ports, and 8-bit event timer counter
21d This is an 8-bit ψ converter with 4 channels of analog input terminals and one serial output terminal.

Therefore, the resolution of the light intensity value is 8 bits, and the dimming setting value is the range of this resolution divided into 10 steps. As shown in FIG. 5, the 8-bit event timer counter of the 8749 is used. This counter can count an internal clock of, for example, 80 μs, which is 1/480 of the oscillation frequency of The input external clock C can be counted. Therefore, since the frequency of the external clock C can be freely adjusted outside the MPU 7, the duty frequency and the resolution of the duty ratio can be freely set. Also, when this counter overflows, it is detected and the output state of the PWM signal is inverted. By controlling the reset value of this counter, the duty ratio of about 1 kHz can be changed from 10 to 1.
A PWM signal that changes to 00% is generated.

The integrator 4 consists of two stages of integrating amplifiers connected, and the integrated output of the first stage is compared with the reference value of the second stage, and the output is expressed as A.
/1) It is output to the converter 5 and also to the transistor Q. As a result, the weight input of the MPU 7 is "1" until the light amount of the fluorescent lander 1 reaches a predetermined value or more, and then "0"), and upon detecting this, the MPU 7 inputs the weight to the port P2.
The PWM signal d output from 4 to the power stabilizer 8 is controlled in different states when the fluorescent rung 1 is rising and when it is steady. In other words, in order to instantaneously start up the fluorescent lamp ``1'', the duty is 100% and the lamp is continuously lit.
When the light intensity of the fluorescent rung 1 falls within the dimming range, the output of the comparator 73 (signal generation method)
9) The duty ratio is changed (hereinafter referred to as signal generation method B), and the light amount of the fluorescent lamp 1 is controlled to be equal to the dimming setting value. The dimming state at this time is displayed by the indicator lamp 17 in a bright and dark state.

18 is a power-on reset circuit, and the power supply film 5TEP
1, when the power is turned on, the circuit 18 detects it and initializes the internal registers. That is, necessary data such as lamp lighting time, pre-copy dimming setting state, pre-copy automatic diagnosis information, etc. are loaded into the non-volatile memory.

Next, in STgP2, dimmer switches SW2 and SW
, 3 to determine the dimming setting value and display it on the dimming position display 9.

5TEP 3 checks the state of the start contact SW1 to determine whether copying is to be started.

When copying starts, input all 11i of books in 5TEP4.
1 Since it is INT -r I J, at a predetermined timing (10) 5TEP Control the pwi signal applied to the PVI/M signal generation signal generation type corporate regulator 8 described above in 5 to 100% duty, Turn on fluorescent lamp 1. Next, 5TE
The self-diagnosis result is displayed on the self-diagnosis result display 10 at P7, and since it is not a copy Stozzo, 5TEP8 is displayed again.
Repeat the process returning to TEP 2.

When the light intensity of the fluorescent lamp 1 reaches a predetermined value, the T meter input changes to “
0'', the transition is made from 5TEP 4 to 5TEP 6.

In 5TEP 6, by comparing the digital signal 1 inputted through the integrator 4 and the φ converter 5 with the dimming signal, the PWM applied to the power supply stabilizer 8 is determined by the above-mentioned groove signal generation method B. (The duty ratio of No. 1 is controlled to match the light intensity of fluorescent lamp 1 with the set light intensity. After that, 5TEP7
The process cycles from 5TEP 8 and back to 5TEP2, and when the start junction '1 becomes QFF and copy paste becomes f, the fluorescent run f1 is turned off at 5TEP 9.
5TEPIO to set lamp off time, copy dimming setting status,
Stores necessary data such as self-diagnosis information into non-volatile memory. Subsequently, in 5TEP11, it is determined whether the power is on, and if the power is off, the series of processes described above ends.

In this way, by comparing the digital signal a and the spotlight signal S and increasing or decreasing the duty ratio of the P'wM signal d according to the deviation, the high frequency power source a applied to the fluorescent lamp 1 can be adjusted.
k 0N-OFF Since dimming control is being performed,
Processing in the MPU 7 is simpler than digital phase control, and communication processing such as self-diagnosis processing, display processing, etc. can be performed in parallel with the 1-chip MPU 7.
, [ru. In addition, since the PWM signal is created using an event timer counter and an external clock, the configuration is simple and the duty frequency and data
You also get the advantage of being able to freely adjust the resolution of the tee ratio.

Incidentally, in the above embodiment, the φ converter 5 and the MPU 7 are constructed using separate IC chips, but the integrated chip f'l
By using z, a more efficient system configuration can be obtained. In addition, the light source is not limited to Fluorescent Lang 1, but Halodan Lang! As described above, according to the present invention, the duty frequency and duty ratio can be easily and accurately determined using a single-chip MPU, and their resolution can be freely adjusted. Thus, an efficient, highly compact, economical and multi-functional digital luminaire generator can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a digital lamp regulator showing an embodiment of the present invention, FIG. 2 is a functional block diagram inside the MPU, FIG. 3 is a waveform diagram for explaining its dimming control operation, and FIG. 4 is a specific configuration diagram of FIG. 1, FIG. 5 is an explanatory diagram of the circuit provided inside the MPU 8749, and FIG.
The figure is a flowchart for explaining the operation of an embodiment of the present invention. 1...Fluorescent Lande, 2...Optical Fine-13...
・Receiver, 4... Integrator, 5... Converter, 6...
・Dimmer setting device, 7...MPU, 8...power stabilizer,
9... Dimming value display, 10... Self-diagnosis result display, 11... External clock generator, 12... Decoder, 13... Jib, 14... Caution lamp, 15 .1
6... Driver, 17... (13) Indicator light, 18... Mother power-on reset circuit, 71...
...Dimmer setting value calculation section, 72...S/P conversion section, 73
...Comparison section, 74゛...Duty ratio calculation section, 75
...Counter section, 76...Chop signal generation section, 7
7...Self-diagnosis section. (14)

Claims (1)

[Claims] In digital lamp regulators that use a microcomputer to control lamp lighting, a high-frequency power source is used as the lamp drive source, and dimming control is performed by turning this high-frequency power source on and off. By providing a clock generator and inputting the generated external clock to a timer event counter built in a microcomputer for counting operation, the 7' unity frequency and duty ratio of the signal for turning on and off the high frequency power supply can be adjusted. is determined using the timer event counter.