JPS5941280B2 - Battery checker for emergency lights - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a battery checker for emergency lights.

The emergency light battery checker checks whether the storage battery, which is the power source for emergency lights used during a commercial power outage, has the capacity to maintain emergency lighting for a specified period of time. The test involves turning off the power, turning on the emergency lights, and testing whether the storage battery maintains a voltage above a certain level even after a certain period of time has elapsed.

FIG. 1 is a circuit diagram of an emergency light that is the basis of this invention.

In the figure, 1 is a commercial power source, 2 is a charging circuit, 3 is a storage battery that is an emergency power source, 4 is a relay for detecting a commercial power outage, 5 is a normally closed contact, and 6 is connected to both ends of the storage battery 3 via contact 5. An incandescent lamp is connected as an emergency light source, and T is a battery checker connected to the output terminal of the charging circuit 2. The battery checker T connects a series circuit of a current limiting resistor 10, a display light emitting diode 11, and a switching transistor 12 in parallel with a series circuit of voltage dividing resistors 8 and 9, and connects both ends of the voltage dividing resistor 9 to a lambda. A resistor for compensating for muddy current is connected between the base and emitter of the transistor 12 through a series circuit of the diode 13 and the base resistor 14, and is further connected in parallel with the series circuit between the base resistor 14 and the base and emitter of the transistor 12. 15 and a parallel circuit of a noise absorbing capacitor 16 are connected, and both ends of a series circuit of resistors 8 and 9 are connected to the output terminal of the charging circuit 2. The lambda diode 13 used in the above embodiment has the voltage-current characteristics shown in FIG. 2, and the series circuit of the lambda diode 13 and the resistor Re has a voltage V1 (high operating point) as shown in FIG.
, the current is blocked and the voltage is V. It has a hysteresis characteristic where current conduction occurs at the low operating point. In the emergency light configured in this way, during general use, the storage battery 3 at the output end of the charging circuit 2 is charged when the commercial power is on, and when the commercial power is turned on, charging stops and the normally closed contact of the relay 4 is charged. 5 is closed and the incandescent lamp 6 is turned on) to provide normal lighting.

When checking the function of storage battery 3, use the time shown in Figure 4. artificially cause a commercial power outage to the circuit by, for example, opening the power switch. When a commercial power outage occurs, the incandescent lamp 6 is connected to the storage battery 3 via the contact 5, and as the storage battery 3 discharges, the voltage Ve at both ends decreases, and the lambda diode 13 reaches its low operating point. As shown in FIG. 4, the divided voltage V0 across the resistor 9, which was at a higher voltage, also decreases. Even after a certain period of time, for example 20 minutes has passed, the divided voltage V remains at the low operating point. , the storage battery 3 has a normal capacity, and in that case, the lambda diode 13 maintains the current blocking state and the transistor 1
2 is non-conductive, no current flows through the light emitting diode 11, and no display is performed. Next, within a certain time T2, for example at time t1 as shown in FIG. 4, the divided voltage V9 reaches the low operating point V.
If it becomes lower than , the storage battery 3 does not have a normal capacity, and in that case, the lambda diode 13 that was in the current blocking state changes to the current conducting state, and the base current is supplied to the transistor 12. The light emitting diode 11 becomes conductive and current flows through the light emitting diode 11, the light emitting diode 11 emits light, and it is displayed that the voltage of the storage battery 3 has fallen below a predetermined voltage within time T2. And time T2
When the artificial commercial power outage is lifted, the storage battery 3 is charged through the charging circuit and reaches the required voltage, and the divided voltage V,
corresponds to the required voltage and reaches a voltage lower than the high operating point voltage V1 and maintains its magnitude. That is, once the low operating point voltage V. The lambda diode 13, which has entered the current conduction state due to the following conditions, does not enter the current blocking state because the applied voltage does not exceed the high operating point voltage V1, and the light emission of the light emitting diode 11 is maintained by maintaining the conduction of the transistor 12. However, the state of the storage battery 3 after a certain period of time for battery inspection is memorized and displayed as is. Next, if the storage battery 3 is forgotten to be connected, a pulsating voltage is generated at the terminal of the storage battery 3 to which it should be connected, and the voltage V across the resistor 9 also becomes a pulsating voltage.

At this time, the pulsating voltage V is at the low operating point V during the half cycle. Since the lambda diode 13 has a smaller area than the above, the lambda diode 13 conducts current, and the light emitting diode 11 emits light due to the conduction of the transistor 12, thereby maintaining the display. Therefore, it is possible to know if the storage battery 3 has been forgotten to be connected. The emergency light that is the basis of this invention can memorize and display the battery check status in this way and prevent forgetting to connect the storage battery 3, but as can be seen from Figure 4, when the commercial power supply 1 is restored to power. In some cases, the light emitting diode 11 continues to emit light even after this, and in such a case, it is impossible to cut off the commercial power supply 1 again and perform an inspection.

Figure 5 shows a different basic circuit designed to eliminate this inconvenience. It is characterized in that a diode 17 is connected in the forward direction, and a bias capacitor 18 is connected in parallel with the series circuit formed by the diode 17 and the contact 5.

In this device, since the contact 5 is open when the commercial power is on, the diode 17 and the capacitor 18 are charged via the diode 17 and the incandescent lamp 6 with the polarity shown. When the commercial power supply 1 is opened from such a state and the battery checker 7 enters the inspection state, the contact 5 closes, so that the charging voltage of the capacitor 18 is superimposed on the voltage of the battery 3, and the series circuit of the resistors 8 and 9 is As a result, the voltage V, instantaneously becomes larger than the high operating point V1, and the lambda diode 1
3 enters a current blocking state, the light emitting display of the light emitting diode 11 stops, and the battery checker 7 is reset. Note that the hysteresis characteristic of the battery checker may be achieved not only by a lambda diode but also by a Schmitt circuit, and the display element is not limited to a light emitting diode. In this way, the battery checker was reliably set, but the battery
If you forget to connect the AC voltage, it should be the rectified waveform of the AC voltage as shown in Figure 6A, and it will always be at the low operating point V.

Although the current 111 should flow through the light emitting diode 11 as shown by the diagonal line, the voltage V, due to the action of the capacitor 18, has the lowest instantaneous value, the valley point voltage. Low operating point V. The problem is that the lambda diode 13 does not change to a current conducting state, so no current flows to the light emitting diode 11, and there is a problem that the connection of the storage battery 3 may not be indicated by light emission. Therefore, the present invention aims to eliminate such drawbacks by connecting a resistor 19 in parallel with the bias capacitor 18 in the battery checker 7 of FIG. 5 as shown in FIG. It is a feature.

In such a circuit, under commercial power supply, the capacitor 18 is charged with the indicated polarity in the same manner as in FIG. 5, the resetting action is performed smoothly, and the storage battery 3
If the connection is forgotten, the resistor 19 acts to alleviate the ripple absorption effect of the capacitor 18, as shown in Fig. 8.
Low operating point voltage V without raising the valley point voltage of the pulsating voltage V too much.

It is possible to normally perform light emitting display by maintaining the current 111 as below and providing a section in which the current 111 flows through the light emitting diode 11. As described above, according to the present invention, the capacity of the storage battery is checked by an artificial power outage for a certain period of time to indicate a defective storage battery, and at the same time, forgetting to connect the storage battery is accurately detected and displayed. This has the effect that the display is inactivated and a set can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of an emergency light that is the basis of this invention, Fig. 2 is a voltage-current characteristic diagram of a lambda diode, Fig. 3 is a characteristic diagram of a hysteresis circuit using a lambda diode, and Fig. 4 is a diagram similar to that shown in Fig. 1. 5 is a different circuit diagram that is the basis of this invention, FIG. 6 is a waveform diagram thereof, FIG. 7 is an embodiment circuit diagram according to this invention, and FIG. 8 is a characteristic diagram thereof. . 3...Storage battery, 4...Relay, 5...
...Relay contact, 7...Battery checker, 8, 9...Resistance for voltage division, 11...
・Light-emitting diode, 12...Transistor, 1
3...Lambda diode, 14...Base resistance, 17...Diode, 18...
...Bias capacitor, 19...Resistance.

Claims (1)

[Claims] 1 An emergency light connected to the output end of a charging circuit for charging a storage battery connected to an emergency light source through a power failure detection contact that detects and closes a commercial power outage, detects the battery voltage of the storage battery, and displays the required display. In the battery checker for
The battery checker body is configured to activate the display at the low operating point of the hysteresis circuit and deactivate the display at the high operating point. A diode is connected in series with the input terminal of the battery checker, and a power outage is detected through this diode. A battery checker for emergency lights that features a parallel circuit of a bias capacitor and resistor connected in parallel with the contacts.