JPH03118771A - Inverter type of power source device - Google Patents

Abstract

PURPOSE:To improve the safety of a device by inhibiting the operation of an output part until a set time passes after load and the output part are changed over from nonconnected condition to connected condition. CONSTITUTION:When the replacement of a fluorescent lamp 5 is completed and the fluorescent lamp 5 and a power source device 6 return from nonconnected condition to connected condition, a delay circuit 15 inhibits the operation of the power source device 6 until a set time passes. The delay circuit 15 charges a capacitor C, whose one end is earthed, with the voltage V3 at the connection between the filament on a rectifier 3 side and the capacitor 14 for lighting through a resistance R, and when the charge voltage of the capacitor C becomes above the set value, it supplies the charge voltage of the capacitor C as the power source voltage VCC of the power source device 6. After the power source device 6 starts the operation, when the power source voltage Vcc of the power source device 6 becomes above the set value, a transistor Q1 is turned on, and the charge voltage of the capacitor C is discharged.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides an inverter-type output section that supplies operating power to a load and the load are detachably provided via a connector, and the output section The present invention relates to an inverter-type power supply device that is configured to continue operating with the output power while the load is connected, and to stop operating when the connection to the load is severed.

[Conventional technology]

The above-mentioned type of inverter type power supply device is used as a power supply device in which a load and an output section are detachably provided via a connector, such as, for example, a fluorescent lamp.

Therefore, if the connection between the load and the output section is cut off without stopping the operation of the output section, there is a risk of electric shock, etc.
It has been considered to configure the output section to continue operating with its output power while a load is connected, and to stop operating when the connection to the load is severed.

[Problem to be solved by the invention]

However, the conventional configuration described above did not have sufficient safety and there was room for improvement.

For example, when the load and output unit return from a disconnected state to a connected state in order to replace a fluorescent lamp or the like as a load, the output unit immediately starts its operation, and if the connection is incomplete, There was a risk of inconveniences such as electric shock.

The present invention has been made in view of the above circumstances, and its purpose is to improve the safety of the device.

[Means to solve the problem]

In the inverter type power supply device according to the present invention, an inverter type output section that supplies operating power to a load and the load,
The output section is detachably provided via a connector.
The device is configured to continue operating with the output power while the load is connected, and to stop operating when the connection to the load is cut off, and its characteristic configuration is as follows: It is as follows.

That is, a delay means is provided for prohibiting the operation of the output section for a set time after the load and the output section are switched from a disconnected state to a connected state.

[For production]

In other words, after the connection between the load and the output section is broken,
Even if the load and output section are switched from a disconnected state to a connected state, the operation of the output section is prohibited for a set period of time, so even if the load and output section are returned to a connected state, This prevents the output section from operating immediately.

〔Effect of the invention〕

Therefore, even if the load and the output section are switched from a disconnected state to a connected state, the output section does not start operating immediately, so there is no risk of accidents such as electric shock. As a result, it has become possible to improve the safety of the device.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, an embodiment in which the present invention is applied to a power supply device for a fluorescent lamp will be described based on the drawings.

As shown in the drawing, alternating current supplied from a commercial power source via a power switch (1) is input to a rectifier (3) via a noise prevention power filter (2) and converted to direct current. It is operated by DC power and has a connector (
The power supply device (6) as an output section is configured as an inverter type so as to supply operating power to the fluorescent lamp (5) as a load via the power source (6) as an output section.

However, although not described in detail, two sets of the power supply devices (6) having the same configuration are provided so that the two fluorescent lamps (5) can be turned on individually.

To explain the configuration of the power supply device (6), an oscillator (7) whose oscillation frequency can be varied, an output transistor (8) which is turned ON10FF by the output signal of the oscillator (7), and an output (Vb) of the rectifier (3). ) and a collector of the output transistor (8), and a resonant circuit (11) comprising an inductance (9) connected between the collector of the output transistor (8) and a capacitor (10) connected in parallel to the inductance (9);
A choke coil (12) that also serves as a transformer is connected between the output of the resonant circuit (11) and the connector (4).
The main parts are:

That is, the power supply device (6) is operated by the electric power converted into DC by the rectifier (3), and supplies the high-frequency AC voltage boosted by the resonance circuit (11) to the filament of the fluorescent lamp (5). It is configured to be supplied to one side. Note that the other side of the filament of the fluorescent lamp (5) is connected to the output (Vb) of the rectifier (3) via the connector (4).

The power supply device (6) continues to operate with its output power while the fluorescent lamp (5) is connected;
In addition, in order to stop the operation when the connection to the fluorescent lamp (5) is cut off, the voltage obtained by rectifying the electromotive force by the choke coil (12) is set to the power supply voltage (V
cc).

However, since no current flows through the choke coil (12) until the power supply device (6) starts operating, when the power is turned on, the output of the rectifier (3) and the power supply device (6) do not flow.
) is connected between the rectifier (3) and the rectifier (3) only for a set time until the power supply (6) is activated and current flows through the choke coil (12). It is configured to supply operating power from the side.

Moreover, between the pair of filaments of the fluorescent lamp (5),
The power supply device (6) is connected to the power supply device (6) via the choke coil (12).
) A lighting capacitor (14) for energizing each of the pair of filaments with a high frequency current supplied from the
is connected. That is, when the power switch (1) is turned on and the power supply device (6) starts operating, the fluorescent lamp (5) is filament (
Electricity is started to be applied to the filaments, and a high voltage is applied between the pair of filaments, and each of the filaments of the pair is preheated. However, after the fluorescent lamp (5) is turned on, the impedance between the pair of filaments decreases greatly as a result of discharge, so the value of the current flowing through the capacitor (14) decreases and the current flowing into the filament decreases. The current applied to the fluorescent lamp (5) is automatically reduced, and the fluorescent lamp (5) continues to be lit due to discharge.

By the way, due to deterioration due to use, the fluorescent lamp (5)
When replacing the power switch (
Basically, it is replaced after turning off the power switch (1), but sometimes the power switch is replaced while the power switch (1) is turned on. In this way, when the fluorescent lamp (5) is removed while energized, the fluorescent lamp (5) is removed while the high frequency voltage is applied.
) and the power supply device (6), and there is a risk of electric shock due to discharge at the connector (4).

Therefore, the choke coil (12) is formed into a transformer so that the power supply device (6) continues to operate due to the electromotive force generated by the current flowing through the choke coil (12). ), the supply of operating power to the power supply device (6) is cut off, and the power supply device (6) automatically stops operating.

Therefore, when the replacement of the fluorescent lamp (5) is completed and the fluorescent lamp (5) and the power supply device (6) return from the disconnected state to the connected state, current flows through the choke coil (12) and the power source The supply of operating power to the device (6) will be resumed, but if it starts operating immediately upon restoration of the connection, accidents such as electric shock may occur due to the high voltage generated at the connector (4). There is a risk.

Therefore, even if the fluorescent lamp (5) and the power supply device (6) return from the unconnected state to the connected state, a delay means for prohibiting the operation of the power supply device (6) until the set time elapses. A delay circuit (15) is provided.

To explain the delay circuit (15), the voltage (Va) at the connection point between the filament on the rectifier (3) side and the lighting capacitor (14) is connected to a capacitor (C) whose one end is grounded. Charge through a resistor (R),
Then, when the charging voltage of the capacitor (C) becomes equal to or higher than the set voltage, the capacitor (C) The charging voltage is connected to the power source of the power supply device (6) through a circuit in which a backflow prevention diode (D) and a varistor (16) are connected in series.

However, after the power supply device (6) starts operating, there is no need for the delay circuit (15) to supply power to the power supply device (6), so the power supply voltage (Vc) of the power supply device (6)
A switch transistor (Ql) is provided that turns on when c) exceeds a set value.
, ) is turned ON, the charging voltage of the capacitor (C) is discharged. Furthermore, if the delay circuit (15) is activated when the power switch (1) is turned on for the first time, lighting of the fluorescent lamp (5) will be delayed, so that the output from the rectifier (3) will be delayed. a diode (17) that discharges the charging voltage of the capacitor (C) of the delay circuit (15) when the power supply is cut off;
is connected in parallel to the charging resistor (R).

In the figure, (Dz) is the power supply voltage (
This is a constant voltage diode for limiting the voltage (Vcc) below a set value.

By the way, in order to stabilize its output voltage, the power supply device (6) detects the voltage value at the connection point between the choke coil (12) and the fluorescent lamp (5), and adjusts the voltage according to the detected voltage. The output voltage is automatically adjusted by varying the oscillation frequency of the oscillator (7).

In other words, the voltage applied to the fluorescent lamp (5) is the same as the voltage applied to the resonant circuit (
11), since the pressure is increased by
The output frequency of the power supply device (6) is determined by the resonant circuit (11).
) when it matches the resonant frequency, it is approximately at its maximum, and decreases as it moves away from the resonant frequency.

Therefore, the choke coil (12) and the fluorescent lamp (5)
) and two resistors connected in series (
18) and (19), and a transistor (Q2) whose collector-emitter conduction resistance changes according to the divided voltage is provided.
) to automatically adjust the oscillation frequency of the oscillator (7).

Further, by varying the oscillation frequency of the oscillator (7), the output voltage of the power supply device (6), that is, the fluorescent lamp (
5) Since the brightness at the time of lighting can be varied by varying the voltage supplied to the fluorescent lamp (5), the fluorescent lamp (5) can be turned on at 100% and then the set light amount is reduced, for example, when it is turned on at 60%. This allows you to switch between them.

To explain, the power switch (1) includes the 10
A contact point is provided to switch between 0% lighting and 60% lighting, and it turns ON when switched to 60% lighting.
An active dimming transistor (Q,) is provided, the collector of which is connected in parallel to the collector of the output voltage regulating transistor (Q2) via a resistor (20).

However, when the power supply device (6) starts operating from the state where the power switch (1) is switched to the 60% lighting position, the supply voltage to the fluorescent lamp (5) is insufficient and the fluorescent lamp (5) cannot be lit normally. (Since there is a possibility that this may occur, when the power supply device (6) starts operating, it starts operating from the above-mentioned lOO% lighting state, regardless of the switching position of the power switch (1), and after that, after the set time has elapsed, Accordingly, the lighting is automatically switched to the 60% lighting mode.

That is, as the supply of operating power to the power supply device (6) is started, the constant voltage diode (Dz)
The capacitor (22) is charged with the output of A delay circuit (24) for dimming is provided so that the transistor (Q3) is turned on. In the figure, (25) is a night light.

[Another example]

In the above embodiment, one of the fluorescent lamps (5) and the power supply device (6)
) is switched from the unconnected state to the connected state, and a delay circuit (15 ), but the specific configuration of the delay means can be modified in various ways.

Further, in the above embodiment, the present invention is applied to a lighting control circuit for a fluorescent lamp, but the present invention can be applied to an inverter-type power supply device for various loads, and the specific configuration of each part may vary. Can be changed.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of drawings]

The drawing is a circuit diagram showing an embodiment of an inverter type power supply device according to the present invention. (4)...Connector, (5)...Load, (6)...Output section, (15)...Delay means.

Claims (1)

[Claims] An inverter-type output section (6) that supplies operating power to the load (5) and the load (5) are detachably provided via a connector (4), and the output section (6) is connected to the load (5). An inverter-type power source configured to continue operating with its output power while a load (5) is connected, and to stop operating when the connection to the load (5) is disconnected. The apparatus includes a delay means for prohibiting operation of the output section (6) for a set period of time after the load (5) and the output section (6) are switched from a disconnected state to a connected state. (15) An inverter type power supply device provided with.