JPH0511678Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] This invention relates to a staged dimming device for medical lighting, and more specifically, to adjust soft dimming moods in multiple stages for multi-lamp lighting such as surgical lighting. This invention relates to a light control device that can control light.

[Conventional technology] For example, a conventional lighting light control device was developed in 1975.
There is something described on page 424 of "Practical Electronic Circuits Handbook (2)" published by CQ Publishing Co., Ltd. on October 20th.

As shown in Figure 6, this conventional technology dims an incandescent light bulb LA by applying a trigger pulse obtained from a unidirectional transistor UJT to the gate of a power control triax TR via a pulse transformer PT. .

In other words, the variable resistor VRO connected to the gate circuit of the unidirectional transistor UJT
The light bulb is continuously dimmed by operating the variable resistor VRO of the time constant circuit consisting of a capacitor CO and a capacitor CO.

[Problems to be solved by the invention] The above-mentioned conventional technology applies an inrush current to the incandescent light bulb LA when it is turned on, which has a negative effect on the life of the incandescent light bulb. If you want to speed up deterioration and reduce the inrush current as much as possible, you have to start the control variable resistor VRO from the lowest position, which is a cumbersome operation.

In order to eliminate each of the above-mentioned problems, this invention uses a step-type dimmer circuit with multiple mutually cancelable push switches in the dimmer circuit operating section, so that the desired illuminance can be adjusted with a single touch. Not only can you choose, but also fade-in.
The purpose is to eliminate inrush current to the light bulb and control components through the fade-out effect, protect each component, and enable shift adjustment of the dimming step illuminance change step setting within about ±20%. do.

[Means for Solving the Problems] The object of the invention described above is to provide at least three or more mutual release type push switches, a bleeder circuit that divides the DC voltage generated in response to the operation of the mutual release type push switches, A fade-in/fade-out circuit that charges and discharges a capacitor by applying a variable voltage divided by this bleeder circuit, a triangular wave generating circuit that generates a triangular wave voltage with a repetition frequency corresponding to the frequency of the AC power source, and a triangular wave generating circuit that generates a triangular wave voltage with a repetition frequency corresponding to the frequency of the AC power source. A shift amount adjustment section for a changing load power setting value, a trigger pulse output section consisting of a differential amplifier, etc. to which the DC voltage that has passed through the fade-in/fade-out circuit and the triangular wave voltage are input, and a trigger from this trigger pulse output section. This is accomplished by each comprising a pulse-controlled solid-state relay and a medical lighting lamp connected in series between the solid-state relay and the AC power source.

[Function] Detects a DC voltage that changes in response to the operation of at least three or more mutual release type push switches, and uses this detected voltage to pass through a fade-in/fade-out circuit using capacitor charging and discharging to generate a trigger pulse from a differential amplifier, etc. Input to the input side of the output section.

On the other hand, the level of the triangular wave voltage with a repetition frequency corresponding to the frequency of the AC power source taken out from the triangular wave generation circuit is changed by the load power setting value shift amount adjustment section, and the triangular wave voltage whose level changes is applied to the trigger pulse output section. By inputting to the other input side, the solid state relay is controlled by the variable level trigger pulse obtained from this trigger pulse output section corresponding to each operation of the mutual release type push switch, and this solid state relay and the above It has the effect of being able to dim the medical lighting lamp connected between the AC power source in multiple stages and in a soft dimming mood.

[Example] Examples will be described with reference to the drawings.

The general structure of the staged dimming device for medical lighting lamps of this invention is as shown in the system circuit diagram in Figure 1.
First, connect the commercial AC voltage source AC to the primary side of the transformer T1, and connect the low voltage secondary side to the DC constant voltage source circuit.
Connect to DC to obtain the desired constant DC voltage +B.

Next, a plurality of mutually releaseable push switches S0 to S5 are provided, each of which is a well-known mutually releaseable pushbutton switch for switching television channels.

And the mutual release type push switch S0~
A light emitting display element is provided on each of the plurality of output sides of S5.
LED0 to LED5 are provided, and a DC level voltage corresponding to the individual operation of the mutual release type push switches S0 to S5 is taken out from each input side of each of these light emitting display elements LED0 to LED5 through a bleeder circuit BR. The voltage is input to a fade-in/fade-out circuit F using the charging/discharging action of a capacitor.

On the other hand, the low-voltage AC voltage V generated on the low-voltage secondary side of the transformer T1 as shown in FIG. Along with getting
This half-wave voltage V1 is passed through a waveform shaping circuit W (including a polarity reversing circuit) to obtain a substantially square wave voltage V2 as shown in FIG. A supply voltage is applied to the input side of the FC, and its output voltage V3 {FIG. 2 d} is input to a triangular wave generation circuit DT using an integrating circuit.

Next, the triangular wave voltage V4 as shown in FIG. 2e generated on the output side of the triangular wave generating circuit DT and the plurality of mutually cancelable push switches S0 to S5 generated on the output side of the fade-in/fade-out circuit F due to the charging and discharging of the capacitor. In order to compare the DC voltage V0 whose level changes as shown in FIG.
Enter in TC.

The trigger pulse output section TC generates a trigger pulse P as shown in FIG. solid state relay consisting of
The brightness of the medical illumination lamp L is input to the SSR and is controlled in six steps in a soft dimming mood in response to the operation of the mutual release type push switches S0 to S5.

Specific examples of the above-mentioned general components will be described in detail below.

First, transformer T1 and DC constant voltage source circuit DC,
The mutual release type push switches S0 to S5, the light emitting display section LED, the bleeder circuit BR, etc. may be well-known ones, so a detailed explanation thereof will be omitted.

Next is DC isolation and zero cross detection circuit Z
As shown in Fig. 3, a well-known device using a light emitting element LD and a phototransistor PT is used, and
The waveform shaping circuit W is composed of a transistor circuit with a shallow bias and a grounded emitter configuration.

In addition, the shift amount adjustment section FC for the load power setting value is constructed from a parallel circuit of a semi-fixed volume VR and a diode D in FIG. It consists of a Miller integration circuit including a differential amplifier A2 and a capacitor C1.

The next stage trigger pulse output section TC is a differential amplifier A.
At the same time, the trigger pulse P is applied to the first input of the capacitor C, and the DC level is changed to the second input in response to the operation of the mutual release type push switches S0 to S5 through the fade-in/fade-out circuit F due to the charging and discharging action of the capacitor C. The wires are connected so that the voltage VO, which changes slowly, is applied.

Then, the trigger pulse P generated at the output side of the trigger pulse output section TC and whose level changes as shown in Fig. 2g is applied to the input side of the solid state relay SSR, and the output side of the solid state relay SSR is applied to the input side of the solid state relay SSR. If necessary, the medical lighting lamp L is connected to the commercial AC power source AC via the transformer T2.
is connected.

In addition, the part indicated by the symbol INV in FIG. 3 indicates six inverter circuits, and the part indicated by the symbol D1 is a diode for forced discharge of the charge/discharge capacitor C for fade-in/fade-out, and D2
~D6 are respective backflow prevention diodes, R7~R
11 is a bleeder resistor, R12 to R15 are load resistors, R21 to R24 are bias resistors, R
25 to R27 are protective resistors.

The staged dimming device for medical lighting lamps of this invention is constructed as described above, so that the solid-state relay SSR can be powered up in a slow manner in multiple stages in response to the individual operation of the mutual release type push switch. Therefore, it is possible to dim a multi-lamp illumination lamp such as for surgery in 6 steps with a soft dimming mood that is gentle on the eyes.

In other words, when the first mutual release type push switch S1 shown in FIGS. 3 and 4 is pressed, the first light emitting display element LED1 lights up to indicate that the power is 60%, and the voltage division ratio of the bleeder circuit BR ( R10:R11), a 60% level DC voltage as shown by the two-dot chain line in FIG. , the triangular wave trigger pulse P is output at a 60% level as shown by the double-dashed line in Fig. 2 f, the solid state relay SSR is controlled within the power distribution range of 60%, and the medical lighting lamp L is controlled at a power distribution range of 60%. % level, it can be turned on slowly in a fade-in manner according to the charging curve of the capacitor C.

The load power setting value shift amount adjustment unit
By adjusting the fixed resistor VR in FC, the brightness of the lighting lamp L lit at 60% power can be shifted within the range of plus 10% to minus 10% or plus 20% to minus 20%, as shown in Figures 2f, 2g and 4.

Next, when the mutual release push switch S0 for OFF is pressed in the above-mentioned lighting state, the light emitting display element is turned OFF.
At the same time, the LED 0 displays an off light emission, and at this time, no control DC voltage is applied to the second input section of the differential amplifier A3 in the trigger pulse output section TC, so the output side of the differential amplifier A3 Since no trigger pulse is generated and the solid state relay SSR is not triggered, the solid state relay SSR is turned off, but at this time, the accumulated charge in the capacitor C in the fade-in/fade-out circuit F is transferred to the diode D1 and the resistor R1.
1, the DC voltage at the second input section gradually disappears, and the medical illumination lamp L gradually fades out.

Next, if you operate any of the mutual release push switches S2 to S5, each of these mutual release push switches S2
The amount of power change shown in Fig. 4 is obtained in response to the individual operations up to S5, but when the mutual release type push switch S5 is operated, the lighting lamp L is gradually faded in to 100% power directly. It can be turned on.

Note that the surface covers of mutual release type push switches S0 to S5 are semi-transparent, and S0 to S5 are attached to this cover.
If the light-emitting display elements LED0 to LED5 are arranged within the surface cover, the operated mutual release type push switch itself can indicate that it has been operated, which is convenient for use.

[Effects of the invention] Since this invention is configured as described above, it produces the effects described below.

Since a step-type dimming circuit with multiple mutually releasing push switches is used in the dimming circuit operating section, the hold IC required for the tact switch operating circuit is not required, making implementation possible at low cost and meeting the user's wishes. In addition to being able to select the illuminance with a single touch, the fade-in/fade-out function eliminates inrush current to the bulb and control components, protecting each component, and making it possible to change the illuminance during dimming steps. Adjust the step setting to ±
This has the effect of allowing shift adjustment within about 20%.

[Brief explanation of the drawing]

Figures 1 to 5 are all based on this idea.
1 is a systematic circuit diagram, FIG. 2 a, FIG. 2 b, FIG. 2 c, FIG. 2 d,
Figures 2e, 2f, and 2g are waveform diagrams for explaining the operating states, Figure 3 is a specific circuit configuration diagram of the circuit shown in Figure 1, and Figure 4 is a diagram showing a plurality of mutually connected circuits. FIG. 5 is a perspective view showing an example of a medical lighting lamp, and FIG. 6 is a circuit diagram of a conventional dimming circuit. S0~S5... Mutual release type push switch,
BR...bleeder circuit, AC...alternating current power supply, F...
...Fade-in/fade-out circuit, DT...
Triangular wave generation circuit, L...Medical lighting, FC...
Load power setting value shift amount adjustment section, TC...Trigger pulse output section, SSR...Solid state relay.

Claims (1)

[Scope of utility model registration request] A lighting light dimmer device using a solid state relay SSR includes at least three or more mutually releasing push switches S0 to S5, and a bleeder circuit that divides the DC voltage generated in response to the operation of the mutually releasing push switches. BR, a fade-in/fade-out circuit F that charges and discharges a capacitor by applying a variable voltage divided by this bleeder circuit BR, and a triangular wave generating circuit that generates a triangular wave voltage with a repetition frequency corresponding to the frequency of the AC power source AC.
DT, a load power setting value shift amount adjustment unit FC that changes the level of the triangular wave voltage, and a trigger pulse output consisting of a differential amplifier, etc. to which the DC voltage that has passed through the fade-in/fade-out circuit F and the triangular wave voltage are input. A medical lighting lamp L connected in series between the solid state relay SSR and the AC power supply AC. A staged dimming device for medical lighting lamps comprising: