JPS6012237Y2 - Smoke detectors - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to smoke detectors.

Conventionally, smoke detectors have been put into practical use that detect the generation of smoke from a fire and sound a buzzer to issue a fire alarm.

The present invention integrates a photoelectric smoke detector, which is a type of smoke detector, and an indicator light, and is equipped with a commercial AC power source and a secondary battery as power sources, and turns on the indicator light in the event of an AC power outage or a fire outbreak. This is what I did.

In addition, the present invention is designed to prevent users from forgetting to turn on the manual switch, which is generally installed in smoke detectors with a built-in secondary battery, in order to prevent the battery from discharging when the sensor is being carried around. This improvement was made in consideration of the fact that the sensor would not operate properly if left unattended.

5 Furthermore, the present invention focuses on the fact that the control section of the smoke detector can be driven with a minute current by integrating it into an IC, and the operation of this control section, that is, the smoke detection monitoring drive, is performed by converting an AC power source into a minute power source through a transformer. On the other hand, parts such as alarm buzzers and indicator lights that consume a lot of power and are driven for a short time can be driven by secondary battery power, thereby reducing the capacity of the power transformer and making it more compact. This made it possible.

Embodiments of the present invention will be described below with reference to the figures.

In FIGS. 1 and 2, reference numeral 1 denotes a photoelectric smoke detector, and an indicator light 2 is provided directly below the top of the detector.

3 is the sensor outer case, 4 is the lens, 5 is the indicator light support stand,
6 is a dark box formed between the sensor upper plate 7 and the middle frame 8;
A large number of windows 9, 9... are provided on the side.

10.10 is a partition plate that blocks external light from entering the dark box 6.

This allows only outside air to flow into the dark box 6.

Numerals 11 and 12 are light emitting elements and light receiving elements provided in recesses 13 and 14 in the middle frame 8, and for example, light emitting diodes and photodiodes are used.

Here, the light-emitting paths 15 of the light-emitting element 13 and the light-receiving paths 14 of the light-receiving element 12 are arranged at an angle so as to intersect at point A in the dark box 6.

Therefore, when the smoke flowing into the dark box 6 scatters the light emitted from the light emitting element 11 near point A, a part of the scattered light enters the light receiving element 12 and is converted into an electrical signal.

Reference numeral 17 is a buzzer that operates when smoke is detected to issue an alarm, 18 is a circuit board, and 19 is an electrical component such as a power transformer.

20, the smoke detector is driven by an AC power source, and 2, which will be described later.
This is a charging indicator light that indicates that the next battery is being charged, and is composed of a light emitting diode.

21 is a manual switch that can manually turn off the indicator light 2 when it is turned on, and 22 is a plug connected to a commercial AC power source.

Although not shown in the figure, a secondary battery 23 (FIG. 3) such as a Ni--Cd battery is installed in the case 3 as a second power source.

FIG. 3 shows the circuit configuration of this embodiment, and 22 is the plug, 24 is a power transformer, 25 is a rectifier diode, 23 is a secondary battery to which DC voltage is applied via a diode 26 to charge it, and 20 is a secondary battery. A charge indicator light that lights up when the secondary battery 23 is being charged; 27, a resistor provided between the diode 26 and the charge indicator light 20; 2, a lamp that lights up during an AC power outage and when smoke detection is activated; 21, the manual switch; Reference numeral 28 denotes a transistor inserted in parallel with the manual switch 21, which becomes conductive when a direct current is applied between its base and emitter through a resistor 32, and functions as an automatic switch.

29. 30 is a switching transistor inserted between the indicator lamp 2 and one end of the power supply, 17 is a buzzer, and 31 is a smoke detector control unit, which has four terminals at b, c, and d. There is.

The terminal a outputs a signal for lighting the light emitting element 11, and the terminal a receives a signal from the light receiving element 12.

In addition, the terminal C outputs a signal when light scattered by smoke enters the light receiving element 12, makes the transistor 30 conductive, and terminal d
Similarly, the control section 31 generates a signal to make the buzzer 17 sound when smoke is detected, and the control section 31 can be implemented as an IC.

Next, the operation will be explained.

When installing a smoke detector, for example, during transportation, the manual switch 21 is kept open to prevent the secondary battery 23 from discharging.

With the manual switch off, when the sensor 1 is mounted on the ceiling or the like and the plug 22 is inserted into an AC power source, the voltage of the AC power source is stepped down, and the DC current obtained by rectification and smoothing is applied to the transistor 28 via the resistor 32. A base current flows through it.

As a result, driving power is supplied to the smoke detector control section 31,
Smoke detectors are in monitoring status.

At the same time, a charging current flows to the secondary battery 23 and charging starts.

Here, the current obtained from the transformer 24 is a minute current of about several tens of microamperes, and only the control section 31 can be driven.

When smoke is detected in such a state, the terminal c of the control unit 31,
A signal is output from d, the buzzer 17 sounds, and the indicator light 2 lights up at the same time.

The power source for driving this buzzer 17 and indicator light 2 is
It is supplied by a secondary battery 23.

In this manner, even if the manual switch 21 is in the open state, charging of the secondary battery 23 and the smoke sensing operation are performed by the AC power source.

On the other hand, if the manual switch 21 is closed after inserting the plug 22 into an AC power source, power is supplied to the control unit 31 via this switch 21, and at the same time, the secondary battery 23 is charged and the sensor is activated. works fine.

If the AC power supply fails while the switch 21 is closed, the transistor 29 becomes conductive via the resistor 27 due to the power supply voltage of the secondary battery 23, and the indicator light 2 lights up.
Acts as a guiding light.

As described above, according to the present invention, even if the manual switch required to prevent discharge of a smoke detector with a built-in secondary battery is left open due to inadvertence, the detector can be operated normally by applying AC power. In addition, the secondary battery 23 can also be charged.

Furthermore, if the manual switch 21 is closed, the indicator light 2 can be turned on and the control unit 31 can be operated normally in the event of an AC power outage. At this time, in order to turn off the indicator light 2, the switch 21 must be opened. Bye.

Further, according to the present invention, the operation of the smoke detector control unit 31, that is, the operation in the monitoring state, is performed using a minute current obtained by stepping down the AC power supply voltage by the transformer 24, and The capacity of the power transformer 24 can be reduced by using the secondary battery 23 to perform the operation in the portion where the current is large.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a sectional view of the embodiment, and FIG. 3 is a circuit diagram of the embodiment. 1...Photoelectric smoke detector, 2...Indicator light, 11...Light emitting element, 12...Light receiving element, 17... Buzzer 21...Manual switch, 23...Secondary battery.

Claims (1)

[Scope of utility model registration request] In a smoke detector powered by a commercial AC power source and a secondary battery charged by the power source, smoke detection and monitoring are driven by a minute power source obtained by stepping down the voltage of the commercial AC power source via a transformer, and A smoke detector characterized in that a fire alarm generating section is driven by the secondary battery power source.