DE3328274A1 - Electronically controlled light - Google Patents

Abstract

The invention relates to an electronically controlled light having a rechargeable power supply section, a charging circuit which can be connected to an external power source, an on-off switch, a lamp which is supplied by the power supply section, and a deep-discharge protection circuit, which is formed by a special design of the on-off switch (A1) and a protection switch (REL), which is controlled via the sensing circuit (T1, T2, T3 etc.) and whose make contact (REL 1) can be bridged over for a limited time, even in the event of a terminal voltage which is excessively low. <IMAGE>

Description

Electronically controlled lamp

The invention relates to an electronically controlled lamp with a rechargeable power supply part, one to an external one Power source connectable charging circuit, an on-off switch, a lamp fed by the power supply part and a deep discharge protection circuit.

Such lights are known, for example, as rechargeable flashlights or emergency lights. If with such lights, Flashlights, emergency lights and the like. The battery voltage of the rechargeable battery below a predetermined one If the value has dropped, an automatic switch-off mechanism switches off the lamp in order to prevent the The battery as this could lead to permanent damage to the battery.

As useful as such an automatic switch-off function is, it can be disadvantageous when in the middle of a job, e.g. a repair on a mast at night, in a dark canal or simply in an emergency situation in the dark suddenly the lights go out without warning.

The object on which the invention is based is thus

to provide a circuit arrangement in such a lamp of the type mentioned above, which despite the already automatic

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After the lamp has been switched off at the table, emergency lighting operation is still possible for a limited short time, which protects against deep discharge temporarily ineffective.

This is achieved according to the invention in that a switch is used as a changeover switch provided with a rest central position on-off switch, a sensing circuit coupled to the power supply part and a circuit breaker controlled by this is provided, which can be switched on by briefly closing the switch-on contact and in normal operation it maintains itself via its normally open contact, which is parallel to the switch-on channel, and that when it is too low Terminal voltage of the battery allows short-term emergency light operation through continuous operation.

Further refinements of the invention are set out in the further claims can be found in detail.

The invention will now be described in more detail using an exemplary embodiment in conjunction with the accompanying drawings explained.

In the drawing you can first see the dash-dotted line Line 1 framed charging circuit, a discharge circuit 2 framed by a further dash-dotted line and the one in between arranged battery circuit 3.

The charging circuit 1 consists of a rectifier DI, the through a capacitor CI and parallel to it a resistor and a light-emitting diode D2 is bridged, as well as two integrated circuits IC 1 and IC 2, which regulate the current and voltage serve via the I-U characteristic. Between

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A resistor R3 is arranged on both integrated circuits. An output of the integrated circuit IC 1 is directly connected to connected to an input of the integrated circuit IC 2. A first output of the integrated circuit IC 2 is via a Capacitor C2 connected to the negative side of the rectifier Dl. The battery part 3 is switched off via a voltage divider the resistors R4, R5 and Ro that are between the positive Potential and the negative side of the rectifier Dl are connected in series and via a diode D4 to the battery Bl, B2 connected. In addition, the connection point between the resistors R4 and R5 is at a second output of the integrated Circuit IC 2 connected. In series with the rechargeable A fuse E2 is provided for battery B1, B2. The sensing circuit 2 is through a voltage divider R7, R8 and R9 coupled, where R8 is an adjustable resistor at the base of a transistor belonging to a bistable circuit Tl is connected. The bistable circuit is a so-called Schmidt trigger and consists of the transistors T1 and T2, the Resistors RIO, RU, R12, R13 and R14 as well as the capacitor C4. The resistor R7 of the voltage divider is through the Capacitor C3 bridged.

An amplifier stage with transistor T3 and resistor R15 is coupled to the Schmidt trigger. In the collector circuit of this transistor there is a relay REL which acts as a circuit breaker and which is bridged by a diode Ό7. Parallel to the transistor T3 and the relay REL is a halogen lamp Hl.

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In addition, the charging circuit is via a diode D3 and the Resistor RIl coupled to the base of transistor T2.

The on / off switch is a rocker switch that acts as a toggle switch Al, between the negative side of the rectifier Dl and the line leading to the lamp Hl in the Is arranged so that it connects once the negative side of the rectifier and thus the battery to the lamp Hl and on the other hand it can be applied to a second contact which is connected to the connection point of the resistors R8 and R9 is connected. The make contact REL 1 of the relay REL bridges the make contact of the switch Al, when the relay REL has picked up.

The mode of operation of this circuit is now as follows:

To switch on the lamp, the switch Al is briefly toggled to the left. This usually causes the sensing disconnection 2 at full voltage and the lamp Hl burns. The Schmidt trigger switches on at T1, off at T2, and thus off switches on T3, the relay REL picks up, closes the contact REL 1 and the lamp Hl stays on because REL is self-contained holds.

If the voltage has dropped below a specified value, and if the lamp Hl is actuated by flipping the switch, the bistable can due to the low battery voltage Do not switch toggle switch, i.e. T1 is blocked, T2 is conductive and T3 is blocked, so that the relay REL has dropped out remain. As soon as the switch Al is released and returns to its rest position in the central position, the lamp goes out.

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So if you want to switch off the lamp for a short time, i.e. for about 10 minutes, for example, maintain an emergency lighting operation, the switch Al must remain actuated to the left.

To switch off the light normally, the switch Al is briefly placed to the right. This will short-circuit the resistor R9. The voltage at the base of Tl is thus too low to have the bistable multivibrator switched on To keep state. The transistor Tl switches off, T2 switches on, and the transistor T3 also switches off, the relay REL drops out, the contact REL 1 opens, and the lamp Hl goes out.

When charging the battery, either through a mains transformer or from the electrical system of a motor vehicle, the charging voltage is based on the diode D3 on the basis of the Transistor T2 coupled. This is used to fool the Schmidt trigger that the battery voltage is too low. Should the toggle switch be switched on, i.e. T2 not conducting and Tl conducting, this operating state is reversed, i.e. T2 switches on, Tl thus switches off, and it also switches off T3, so that the relay REL drops out. If the lamp has not been used, then it can Do not pull the REL relay during the charging process. That means, however, that the lamp Hl always during the charging process is disconnected from the battery.

So you can see that this new circuit also provides an automatic shutdown to prevent deep discharge short-term emergency operation is possible.

In the drawing, the charging of the halogen lamp described is indicated schematically both on the network and on the electrical system of a motor vehicle. In the former case, a transformer M1 is provided to reduce the mains voltage, while a fuse E1 is arranged in the line leading to the mains plug. ..- ■ '- ^

If the light is charged on the on-board network, a current limiting resistor R1 provides an additional one Fuse.

Claims (4)

Diploma Phys. M. Becker 7ooosiuu _R art? O ^r,. ' To your shark ^ sI 29 Patent Attorney η q ο ρ ο ^7/7 ^ ^{0 "(07ii} J 600306 A 3323 -v-kl Witte & Sutor, GmbH Steinberger Strasse 2 7157 Murrhardt Claims Electronically controlled lamp with a rechargeable power supply unit, a charging circuit that can be connected to an external power source, an on-off switch, one through the Power supply part fed lamp and a deep discharge protection circuit, marked by one provided as a switch with a rest center position On-off switch (A1) / a sensing circuit (T1, T2, T3, etc.) coupled to the power supply (B1, B2, R4 to R9) and a circuit breaker (REL) controlled by these, the Can be switched on by briefly closing the switch-on contact and, in normal operation, maintains itself via its normally open contact (REL 1), which is parallel to the switch-on contact, and which allows short-term emergency lighting if the battery terminal voltage is too low. 2. Lamp according to claim 1, characterized in that the Sensing circuit from a bistable multivibrator (T1.T2) and there is an amplifier transistor connected to it, by which the circuit breaker (REL) can be actuated, the Sensing circuit on a parallel to the power supply part ' arranged voltage divider (R7, R8, R9) is coupled, the third resistor (R9) through the switch (A1) at brief actuation to switch off can be bridged. 3. Lamp according to claim 1, characterized in that the Charging circuit with a combination of voltage regulation (IC 1) and current control (IC 2) and connected to the power supply unit via a device (D4) that conducts only in one direction is coupled. 4. Lamp according to claim 2, characterized in that the charging circuit via a one-sided conductive device (D3) coupled to the bistable multivibrator (T1, T2) in this way is that when the power supply part is charging, the circuit breaker (REL) drops.