JPS5858697A - Double sensitivity type sensor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dual-sensitivity type sensor having two sensitivities at which the sensor should operate.

Conventionally, this type of dual-sensitivity sensor has two sensitivity sensors as shown in Figure 1.
A 2-product bad signal line and an 8-product bad signal line DL, which respectively connect the type switching circuit 1 and the 8-type switching circuit 2, are connected to the signal detection circuit via diodes T)t and Da. This signal detection circuit is a detection circuit Hatake and comparison amplification scheme 4.
, a constant voltage diversion 6 including a current limiting circuit, two storage circuits 6 and 7, and a sensitivity change I! It is composed of 8 circuits, and there are few common parts, so an increase in cost due to an increase in the number of parts is unavoidable, and 5J! Hanging was also difficult due to space constraints.

In view of the above reasons, the present invention enables simple sensitivity change from 8 types to 8 types by simply changing the circuit voltage, and also makes the signal processing circuit 9 common and adds only a trigger circuit. The object is to obtain three or eight types of detection with different storage times using only one sensor, and to reduce the number of sensors used by using a common L-sensitivity type sensor and components.

- Two types of switching consisting of a detection unit 8 such as a photoelectric type or ion type sensor, a comparison amplifier circuit 4 that compares and amplifies signals, a constant voltage circuit 6 including a current limiting circuit, and a differential comparator. circuit 1
The type 8 switching circuit 2 is the same as that in the conventional example shown in FIG. A signal processing circuit 9 shapes the waveform of the signal. PNP on both ends of the signal line) Fungisq Trh2 resistance -, diode D4 % capacitor -? q are connected in series, and the base of the transistor Trl is connected to the signal processing circuit 9. The voltage point of the capacitor is connected to the anode of the voltage detection element PUT, the reference voltage of the signal processing circuit 9 is connected to the gate of the voltage detection element Pσ), and its cathode is connected to the 2-type switching circuit 1. be. The side of the transistor Trl is connected to the top 7. J T'rl
It is also connected to the emif l of the transistor, the collector side of pTrl is a resistor island, and the signal line CK! is connected to the diode through the series circuit to the capacitor. ! The voltage point of the capacitor is connected to the anode of the voltage detection element PU1, and the reference voltage from the signal processing circuit 9 is connected to the gate of the voltage detection element PUT.The cathode side is connected to the 8 types of switching circuit. It is connected to 2. The pace of the transistor qTr is connected to the 2-product line through the diode island. Zener diode ZDI, ZD.

sets the voltage for this circuit in °C. Diode D1~
D is a diode for preventing backflow.

In the initial state, each switching circuit 1.2 is in an off state and diode 8 is in a cutoff state. A voltage determined by Zener diode ZD1 is supplied to the circuit. Now, the two-product signal from the electrostatic discharge circuit 8 is multiplied by the comparison amplifier circuit 4, and the signal processing circuit 9 turns on the C transistor 5tTrl.

As a result, the capacitor CI that can set the impression time is charged. When the anode voltage of the C1 voltage detection element PUT1 exceeds the gate voltage of the reference voltage, the voltage detection element PUT1 turns on and triggers the second type switching circuit l. . At this time, the transistor Tr! is OFF, so the voltage detection element P (JT) operates.Here, the inside of the 2-type switching circuit 1 becomes short-circuited, the potential of the 2-product bad signal @L decreases, and the diode 8 changes from OFF to ON. Then, a current flows through the Zener diode ZD, and the circuit voltage changes from the state determined by the Zener diode ZD to the voltage determined by zDl.

Zener diode ZD, is Zener diode ZD1
The performance shall be such that a lower voltage can be set as the circuit voltage. When the voltage decreases, the sensitivity of the detection circuit 8 changes from 2 to 8 without changing the resistance as in the conventional case. The sensitivity of the detection circuit 8 was changed from 2 types to 8 types by changing the resistance etc., but in the present invention, it was changed from 241 to 8 Ja by lowering the circuit voltage instead of the resistance. Blind. At the same time, the transistor Try also appeared in the on state, and the detector 18 reacted to 8 mP and temperature. JTrl,
It passes through I'rl, a resistor, and a diode D to charge the capacitor C8. Capacitor C has a function that allows you to set the emotional time of the 8th class pig. Then, at 9 o'clock, the anode voltage of the voltage detection probe PU exceeds the gate voltage.
The voltage detection element PUN' is turned on and triggers the C8C8 type switch 2.

As described above, the 2nd type sensitivity signal line and 8 which connect the 112th type 2f switching circuit 1 and the 8th type switching circuit 2 separately.
Seed sensitivity signal 4ij line DL and 14 directions da, iode D1
# Connect 1-1 to the signal detection circuit via D2 and constant voltage circuit 6, and receive the signal! The horizontal circuit includes a fire detection circuit, a comparison amplifier circuit 4 that amplifies the detection output and obtains an output by comparing it with a reference voltage, and a signal processing circuit 9 that shapes the waveform of the comparison output signal. The output is 4aL, and a storage section tube is provided to set the impression time, and the composition sensitivity is changed by changing the circuit voltage of the signal processing circuit.
Sensitivity switching between load grade and grade 8 pig grade 2
By using a sensitivity type sensor, the gain of the comparison amplification circuit 4 does not have to be changed using a special sensitivity changing circuit 8 as in the past, but in the present invention, the voltage of the constant voltage circuit 4 is changed by using a Zener diode ZD, It is possible to change the sensitivity key by changing the diode #''D, -1+, and the configuration in which the signal processing circuit 9 is shared and only the trigger circuit at the final stage of °C1 is added allows for different running accumulations with fewer parts used. You can gain time and be effective. “ −′ −

[Brief explanation of the drawing]

8...Detection circuit, 4...Comparison amplifier circuit, 9...Signal processing 3! l @ road, 6... Constant voltage circuit, l... Snow accumulation switching circuit, 2... 3 types of switching circuit, Tr
l... Totsun νsu J, Trl --- Transis J,
CI-φ capacitor, C-capacitor, PUT
l... Voltage detection element, PUT,... Voltage detection element. Patent applicant Matsushita Electric Works Co., Ltd. Representative patent attorney Toshimaru Takemoto (2 people)

Claims (1)

[Scope of Claims] 1) A 3-product bad signal bundle and an 8-product bad signal loop nt, 2 are die-cut in the same direction, in which the type 1 switching circuit 1 and the type 8 switching circuit 2 are connected separately. -DoD, ,D. A detection circuit for detecting fire is connected to the signal detection circuit via a constant voltage circuit 6, and a comparison amplifier circuit 4 which amplifies the detection output and obtains an output by comparing it with a reference voltage. , a signal processing circuit 9 that shapes the waveform of the comparison output signal, and a storage section that stores the shaped output and sets the impression time, and changes the detection sensitivity by changing the circuit voltage of the #i signal detection circuit. 2-sensitivity type sensing II that is designed to change the sensitivity to switch between 2-type sensitivity and 3-type sensitivity.