JP3116120B2 - Water landing detection device and continuity check device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Details of the water landing detection device and the continuity check device of the present invention will be described in accordance with the following items.

A. Industrial application fields B. Summary of the invention C. Prior art [FIG. 4] D. Problems to be solved by the invention E. Means to solve the problems F. Embodiments [FIGS. 1 to 3] Figure] a. Water sensor [Fig. 1] a-1. Water discrimination circuit a-2. Additional circuit for continuity check b. Continuity check device [Fig. 2] c. Check operation [Fig. 3] d. Function G. Effects of the Invention (A. Industrial Application Field) The present invention relates to a water landing detection device and a continuity check device. Specifically, the presence or absence of disconnection of the ignition means in the water landing detection device is determined without removing the ignition means from the apparatus.
An object of the present invention is to provide a water landing detection device and a continuity check device that can be easily checked without any influence on a circuit state of the water landing detection device.

(B. Summary of the Invention) A first invention landing detection device has a positive power supply terminal and a negative power supply terminal to which a DC power supply is connected, a first detection electrode is connected to a negative power supply terminal, A second detection electrode connected to a first output terminal of a discrimination circuit for detecting a current flowing between the pair of detection electrodes when a liquid intervenes between the pair of detection electrodes;
In a water landing detection device in which ignition means operated in response to an ignition signal from a discrimination circuit is connected between first and second output terminals of the discrimination circuit, the positive power supply terminal and a second output of the discrimination circuit are provided. A switch means is provided on a bypass line connecting terminals, and a check signal having a polarity which becomes a back electromotive force with respect to the DC power supply and a voltage value of which generates the DC power supply voltage is input through the pair of detection electrodes. The switch means is sometimes closed to close the bypass line, whereby the disconnection check can be easily performed while the ignition means is connected to the device. The checking device has at least one of a pair of detection terminals connected to a DC power supply through a switch means, and converts current flowing through the detection terminal into a voltage, Comparing means for comparing the output voltage of the current-voltage converting means with the reference voltage, and holding means for temporarily holding the comparison result from the comparing means and transmitting a predetermined signal to the notifying means in response thereto The continuity check device, wherein the switch means is closed for a predetermined time in response to a signal indicating the start of the check operation from the start switch, so that at least one of the detection terminals is connected to the DC power supply, When the disconnection of the ignition means of the water landing detection device is checked, the check can be performed without inducing an unexpected operation of the water landing detection device.

(C. Prior Art) [FIG. 4] There is a device equipped with a pair of detection electrodes, a DC power supply, and a water landing detection circuit for detecting water landing on seawater or the like. The automatic inflation device (ie, in a military airplane or the like, causes a flight failure, which makes it necessary for a pilot or other crew to make an emergency escape above the sea and land in seawater, or a lifeboat or a life jacket) A device for supplying a compressed gas to a seawater) is known.

FIG. 4 is a circuit block diagram schematically showing an example a of a conventional water landing detection device.

In the figure, b is a DC power supply, and its positive electrode is a water landing determination circuit c.
Are connected to one of the power supply terminals d and d '.

e and e 'are a pair of detection electrodes, one of which is connected to the negative electrode of the DC power supply b, and the other e' is connected to the power supply terminal d 'of the discrimination circuit c.

f and f 'are output terminals of the landing determination circuit c, and both terminals of the ignition heater g are connected between the output terminals f and f'.

(D. Problems to be Solved by the Invention) By the way, in order to check the disconnection of the ignition heater g in the above-mentioned water landing detection device a, it is already connected to the output terminals f and f ′ of the water landing determination circuit c. The ignition heater g is removed and tester terminals are applied to both terminals of the ignition heater g, and it is necessary to check whether or not the ignition heater g is disconnected from the resistance value at this time.

Therefore, a disconnection detection circuit and a check terminal are added in advance to the water landing determination circuit c, power is supplied to the disconnection detection circuit at the time of a check operation, a tester terminal is applied to the check terminal, and the current flowing through the ignition heater g is checked. It is also conceivable that the disconnection of the ignition heater g can be known from the presence or absence.

However, such a method complicates the circuit, not only increases the number of parts, causes a malfunction of the circuit accompanying the increase in the number of components, and also increases the cost, but also requires a circuit for detecting a disconnection according to the circuit configuration of the water landing determination circuit c. There is the disadvantage of having to design individually.

(E. Means for Solving the Problems) In order to solve the above-described problems, the present invention has a configuration in which a water landing detection device includes a positive power supply terminal and a negative power supply terminal to which a DC power supply is connected. A first detection electrode connected to a negative power supply terminal, and a second detection electrode for detecting a current flowing between the pair of detection electrodes when a liquid intervenes between the pair of detection electrodes. A landing means connected between the first and second output terminals of the discrimination circuit, the ignition means being operated in response to an ignition signal from the discrimination circuit. A switch means is provided on a bypass line connecting the second output terminals, and a check signal having a polarity which becomes a back electromotive force with respect to the DC power supply and whose voltage value generates the DC power supply voltage is transmitted through the pair of detection electrodes. Switch means is closed when input Ipasurain is obtained so as to close the.

In addition, the continuity check device according to the present invention includes a pair of detection electrodes, a determination circuit connected to the detection electrodes, a DC power supply, and one of a positive power supply terminal of the DC power supply and one of output terminals of the determination circuit. A continuity check device for performing a continuity check of the device by connecting to a detection electrode for a device provided with a switch means provided on a bypass line to be connected and closed at the time of continuity check; It has the configuration shown in (a) to (e).

(A) It has a pair of detection terminals respectively connected to the detection electrodes.

(B) The voltage value of the DC power supply provided in the continuity check device is higher than the voltage value of the DC power supply in the device to be checked for continuity.

(C) one of the detection terminals of (a) is connected to a DC power supply in the continuity check device via a switch means in the device, and a current for converting a current flowing through the detection terminal to a voltage; A voltage conversion unit, a comparison unit for comparing the output voltage of the current-voltage conversion unit with a reference voltage, and temporarily holding a comparison result from the comparison unit, and in response to this, a predetermined signal to the notifying unit. And holding means for sending out.

(D) At the time of the continuity check, the positive terminal of the DC power supply in the continuity check device is connected to one of the detection terminals (a) and the detection electrode connected to the detection terminal. Is connected to the positive power supply terminal of the DC power supply, and the negative terminal of the DC power supply in the continuity check device is connected to the other one of the detection terminals (a) and the detection electrode connected to the detection terminal. Be connected to the negative power supply terminal of the DC power supply in the equipment to be checked.

(E) The switch means of (c) is closed for a predetermined time in response to the signal indicating the start of the check operation from the start switch, so that one of the detection terminals of (a) and the DC power supply in the continuity check device are positive. The side terminals are connected, and the switch means on the bypass line provided in the device to be checked for continuity is closed to close the bypass line. At this time, depending on the magnitude of the current flowing through the continuity check device, Whether the continuity check is correct or not is determined by the comparing means of (b).

Therefore, according to the water landing detection device and the continuity check device of the present invention, the pair of detection electrodes of the water landing detection device and the detection terminals of the continuity check device are separately connected when the disconnection of the ignition unit of the water landing detection device is checked. At the same time, when the start switch of the continuity check device is turned on, the switch means of the continuity check device is momentarily closed, a check signal is sent to a pair of sensing electrodes of the water landing detection device, and the bypass line is switched by the switch means of the water landing detection device. Is closed, the current flowing through the ignition means at this time can be detected by the continuity check device, and the disconnection detection circuit can be individually designed without removing the ignition means, and a check terminal can be added. It is not necessary and can be configured at low cost without increasing the number of parts or inducing circuit malfunction.

(F. Embodiment) [FIGS. 1 to 3] The details of the water landing detection device and the continuity check device of the present invention will be described below with reference to the illustrated embodiment.

(A. Water landing sensor) [FIG. 1] FIG. 1 shows an embodiment of the water landing detection device of the present invention, and the illustrated embodiment is used when the water landing detection device of the present invention lands on seawater. This is applied to a working landing sensor.

In the figure, reference numeral 1 denotes a circuit of a water landing sensor. The water landing sensor 1 includes a water landing determination circuit 2, a DC power supply 4 connected between its power terminals 3, 3 ', and a water landing determination circuit 2. It comprises an ignition heater 6 connected between the output terminals 5 and 5 ', and an additional circuit 7 for checking conduction.

The ignition heater 6 is provided for starting ignition of various operation mechanisms utilizing the explosive power of explosive.

(A-1. Water landing determination circuit) Reference numerals 8 and 8 'denote power supply lines, one end of which is connected to the positive power supply terminal 3 and the other end of which is connected to the output terminal 5 via the continuity check additional circuit 7. It is connected to the.

The other power supply line 8 'connects between the negative power supply terminal 3' and the output terminal 5 'via a pair of detection electrodes 9 and 9' which can be made conductive when detecting landing.

That is, 8'a is a line connecting the power supply terminal 3 'and the detection electrode 9, and 8'b is a line connecting the output terminal 5' and the detection electrode 9 '.

Note that the detection electrode 9 'is connected to a housing made of a conductive material of a device (not shown) using the water landing sensor 1, and is a so-called frame ground, and the detection electrodes 9 and 9' (or the housing) When immersed in seawater, a weak current flows between these electrodes via seawater.

Reference numeral 10 denotes an NPN transistor whose emitter is grounded,
Its collector is connected to a power supply line 8 via a resistor 11, and its emitter is connected to a power supply line 8'b. If the resistor 11 is a variable resistor, it is possible to detect not only seawater but also other liquids.

Reference numeral 12 denotes a Zener diode, whose anode is connected to the collector of the transistor 10 and whose cathode is connected to the power supply line 8 via a resistor 13.

14 is a PUT whose gate is a Zener diode 12
And a resistor 13, the anode of which is connected to the power supply line 8, and a capacitor 15 interposed between the gate and the anode. The cathode of the PUT 14 is connected to a power supply line 8 'through resistors 16 and 17 connected in series.
b.

Reference numeral 18 denotes an NPN transistor whose emitter is grounded,
Its base is connected between resistor 16 and resistor 17,
Its collector is connected to the base of transistor 10 and to power supply line 8 via resistor 19, and its emitter is connected to power supply line 8'b.

Reference numeral 20 denotes a diode, whose anode is connected to the cathode of the PUT 14, and whose cathode is connected to the positive terminal of an electrolytic capacitor 21 as an ignition capacitor. The negative terminal of the electrolytic capacitor 21 is connected to the power supply line 8'b.

Note that, when the sensing electrodes 9 and 9 'are immersed or not immersed in seawater due to a change in the seawater surface at the time of landing, the terminal potential of the electrolytic capacitor 21 becomes PU.
It is provided so as not to affect the operation state of the discriminating circuit consisting of T14 and the transistors 10 and 18, thereby ensuring the reliability of the charging operation of the electrolytic capacitor 21 when landing on seawater. Can be.

Reference numeral 22 denotes a resistor, which is connected to the electrolytic capacitor 21 in parallel.

23 is a Zener diode whose anode is connected to the power supply line 8'b and whose cathode is a resistor.
It is connected to the cathode of the diode 20 via 24.

25 is a PUT whose gate is a Zener diode 23
The resistor 24 has an anode connected to the anti-Zener diode 23 side terminal of the resistor 24, and a capacitor 26 interposed between the gate and the anode. Further, the cathode of the PUT 25 is connected to the output terminal 5.

(A-2. Additional circuit for continuity check) The additional circuit for continuity check 7
A diode 27 and a resistor 28 are provided on a bypass line 8a connecting the anode of the output terminal 4 and the output terminal 5. The cathode of the diode 27 is connected to the power supply line 8 and the anode of the diode 27 is output via the resistor 28. Connected to terminal 5.

(B. Continuity Checking Device) [FIG. 2] Next, the circuit configuration of the continuity checking device 29 will be described.

In the figure, reference numeral 30 denotes a DC power supply, one of the power supply lines 31, 31 '.
31 is a plus line and 31 'is a minus line. Note that the power supply voltage value of the DC power supply 30 is set to be higher than the power supply voltage value of the DC power supply 4 of the landing sensor 1.

32 is a push button switch, one end of which is a plus line 31
, And the other end is connected to an input terminal of a switch control circuit 34 for controlling the opening and closing of a switch 33 provided on the plus line 31. Then, when the push button switch 32 is pressed, the switch 33 is closed only for a short time defined by the switch control circuit 34, and such a switch 33 and the switch control circuit 34 are, for example,
It can be configured using a one-shot multivibrator IC. The reason why the continuity checking device 29 is operated only for a short time is that if the current flowing through the ignition heater 6 of the water landing sensor 1 is large at the time of the continuity check, the ignition of the ignition heater 6 causes sudden ignition of the ignition ball. This is to avoid a problem such as a possibility that the battery may occur, and damage to a battery used as the DC power supply 4.

35 and 35 'are a pair of tester terminals, one of which is connected to a switch 33 via a series-connected resistor 36 and a constant current diode 37, and the other 35' is connected to a minus line 31 '. I have.

Numeral 38 denotes a differential amplifier, and two input terminals are respectively connected to both terminals of the resistor 36.

A comparator 39 has a plus input terminal connected to the output terminal of the differential amplifier 38, and a minus input terminal connected to voltage dividing resistors 40 and 41 provided between the power supply lines 31 and 31 '.
Is connected between.

42 is an RS flip-flop, the set terminal of which is connected to the output terminal of the comparator 39;
The reset terminal is connected to the plus line 31 via a reset switch 43, and the Q output terminal is connected in series to a resistor.
It is connected to the minus line 31 'via 44 and 45.

46 is an NPN transistor whose base is composed of resistors 40 and 4
The collector is connected to the plus line 31 via the resistor 47 and the LED 48, and the emitter is connected to the minus line 31 '.

(C. Check Operation) [FIG. 3] Next, a circuit operation at the time of checking for disconnection of the ignition heater 6 using the continuity check device 29 will be described.

FIG. 3 shows the landing sensor 1 at the time of disconnection check.
3 shows an equivalent circuit of the continuity check device 29.
That is, in the equivalent circuit 49 of the water landing sensor 1, the detection electrode 9 'is connected to the positive electrode of the DC power supply 4 via the ignition heater 6, the resistor 28, and the diode 27, and the detection electrode 9 is connected to the negative electrode of the DC power supply 4. It is connected.

Note that the resistance value of the ignition heater 6 is r (Ω), the resistance value of the resistor 28 is R (Ω), the forward voltage drop of the diode 27 is V _F (V), and the voltage value of the DC power supply 4 is e. (V).

On the other hand, in the equivalent circuit 50 of the continuity check device 29, the tester terminal 35 is connected to the ammeter 51 via the switch 33 (actually, as described above, the voltage is detected by the resistor 36 and detected. The detection target is the current) via the DC power supply
The tester terminal 35 ′ is connected to the negative electrode of the DC power supply 30. Note that if the voltage value of the DC power supply 30 is E (V), E> e.

Then, the tester terminals 35 and 3 of the continuity check device 29
One 35 of 5 'is connected to the detection electrode 9' of the landing sensor 1, and the other 35 'is connected to the detection electrode 9.

When the push button switch 32 is pressed, the switch 33 is closed for a short time. Therefore, when the ignition heater 6 is not disconnected, a current flows, and if this current value is I, Is detected by the continuity check device 29.

When the ignition heater 6 is disconnected, I ≒ 0.

The actual circuit operation of the continuity check device 29 is as follows. The differential amplifier 38 detects the voltage generated at the terminal of the resistor 36 due to the flow of the current I, and the output value and the voltage dividing resistors 40 and 41 define the voltage. The comparison with the reference voltage value is performed by the comparator 39, and the output of the comparator 39 is R−
Latched by S flip-flop 42, transistor
By turning on / off 46, the LED 48 is turned on or blinks, and the disconnection or conduction of the ignition heater 6 is notified. That is, the voltage dividing resistance
Assuming that the resistance values of 40 and 41 are R ₄₀ (Ω) and R ₄₁ (Ω) respectively,
When the current I flows through the resistor 36, the comparator 39
Positive input voltage Each resistance value is chosen to be larger.

When the water landing sensor 1 is used, when the detection electrodes 9 and 9 'come into contact with seawater, the detection electrodes 9, 9'
The current flowing between 9 'is voltage-converted by the resistor 13, and this value is determined by the Zener diode 12 and the PUT 14 to be equal to or higher than the Zener voltage, the PUT 14 and the transistor 18 are turned on, the transistor 10 is turned off, and the electrolytic capacitor is turned off. When the terminal 21 is charged and its terminal voltage becomes equal to or higher than the Zener voltage of the Zener diode 23, the PUT 25 is turned on and a current flows through the ignition heater 6. When the detection electrodes 9 and 9 'are not immersed in seawater or when only rainwater or the like is applied, the PUT 14, the transistors 10 and 18 operate in a completely opposite manner to the above, and a current flows through the ignition heater 6. There is no.

(D. Operation) However, when the disconnection of the ignition heater 6 of the water landing sensor 1 is checked, the positive electrode of the DC power supply 30 of the continuity check device 29 → the switch 33 → the tester terminal 35 → the detection electrode 9 ′ of the water landing sensor 1 → the ignition heater 6 → resistor 28 → diode 27 → DC power supply 4 → detection electrode 9 → tester terminal 3 of continuity check device 29
A circuit of 5 '→ negative electrode of the DC power supply 30 is formed, and by detecting the current I flowing through the circuit, the presence or absence of disconnection of the ignition heater 6 can be easily checked.

That is, the continuity check additional circuit 7 only needs to be provided for the water landing sensor 1, the detection electrodes 9, 9 'can be used as check terminals, and the continuity check device 29 is switched by the switch control circuit 34.
With the instantaneous switching control of 33, it is possible to avoid unexpected ignition of the ignition ball by the ignition heater 6.

(G. Effects of the Invention) As is clear from the description above, the first invention water landing detection device has a positive power supply terminal and a negative power supply terminal to which a DC power supply is connected, and The detection electrode is connected to a negative power supply terminal, and the second detection electrode is connected to a first output terminal of a discrimination circuit that detects a current flowing between the pair of detection electrodes when a liquid intervenes between the pair of detection electrodes, In a water landing detection device in which ignition means operated in response to an ignition signal from a discrimination circuit is connected between first and second output terminals of the discrimination circuit, the positive power supply terminal and a second output of the discrimination circuit are provided. A switch means is provided on a bypass line connecting terminals, and a check signal having a polarity which becomes a back electromotive force with respect to the DC power supply and a voltage value of which generates the DC power supply voltage is input through the pair of detection electrodes. When the switch means the bypass line is closed Characterized by being adapted to close.

In addition, the second invention continuity check device includes a pair of detection electrodes, a determination circuit connected to the detection electrodes, a DC power supply, and one of a positive power supply terminal of the DC power supply and an output terminal of the determination circuit. A continuity check device for performing a continuity check of the device by connecting to a detection electrode for a device provided with a switch means provided on a bypass line to be connected and closed at the time of continuity check; The features described in (a) to (e) are characterized.

(A) It has a pair of detection terminals respectively connected to the detection electrodes.

(B) The voltage value of the DC power supply provided in the continuity check device is higher than the voltage value of the DC power supply in the device to be checked for continuity.

(C) one of the detection terminals of (a) is connected to a DC power supply in the continuity check device via a switch means in the device, and a current for converting a current flowing through the detection terminal to a voltage; A voltage conversion unit, a comparison unit for comparing the output voltage of the current-voltage conversion unit with a reference voltage, and temporarily holding a comparison result from the comparison unit, and in response to this, a predetermined signal to the notifying unit. And holding means for sending out.

(D) At the time of the continuity check, the positive terminal of the DC power supply in the continuity check device is connected to one of the detection terminals (a) and the detection electrode connected to the detection terminal. Is connected to the positive power supply terminal of the DC power supply, and the negative terminal of the DC power supply in the continuity check device is connected to the other one of the detection terminals (a) and the detection electrode connected to the detection terminal. Be connected to the negative power supply terminal of the DC power supply in the equipment to be checked.

(E) The switch means of (c) is closed for a predetermined time in response to the signal indicating the start of the check operation from the start switch, so that one of the detection terminals of (a) and the DC power supply in the continuity check device are positive. The side terminals are connected, and the switch means on the bypass line provided in the device to be checked for continuity is closed to close the bypass line. At this time, depending on the magnitude of the current flowing through the continuity check device, Whether the continuity check is correct or not is determined by the comparing means of (b).

Therefore, according to these, when the disconnection of the ignition means of the landing detection device is checked, the pair of detection electrodes of the landing detection device and the detection terminal of the conduction checking device are separately connected, and the start switch of the conduction checking device is turned on. The switch means of the continuity check device is momentarily closed, a check signal is sent to the pair of detection electrodes of the water landing detection device, and the bypass line is closed by the switch device of the water landing detection device. The current flowing through the ignition means can be detected by the continuity check device, without removing the ignition means, there is no need to individually design a disconnection detection circuit or add a check terminal, and the number of parts is increased. And can be configured at low cost without inducing circuit malfunction.

It should be noted that the discrimination circuit of the water landing detection device of the present invention is not limited to the water landing discrimination circuit shown in the above-described embodiment, and the technical scope is not narrowly understood. Of course.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS The drawings show an embodiment in which the water landing detection device of the present invention is applied to a water landing sensor and a continuity check device of the water landing sensor. FIG. 1 is a circuit diagram of the water landing sensor, and FIG. Is a circuit diagram of a continuity check device, FIG. 3 is an equivalent circuit diagram of a water landing sensor and a continuity check device, and FIG. 4 is a circuit block diagram schematically showing an example of a conventional water landing detection device. DESCRIPTION OF SYMBOLS 1... Water landing detection device 2... Discrimination circuit 3... Positive power supply terminal 3 ′... Negative power supply terminal 4... DC power supply 5 ′ 1. 5: second output terminal, 6: ignition means, 8a: bypass line, 9: first detection electrode, 9 ': second detection electrode, 27: switch means, 29: conduction Check device, 30 DC power supply, 32 Start switch, 33, 34 Switch means, 35, 35 'Detection terminal, 36, 38 Current-voltage conversion means, 39 Comparison means, 42 …… Holding means, 46, 48 …… Notification means

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01R 31/02 G01M 3/16 G01N 27/06

Claims (2)

(57) [Claims] A first power supply terminal connected to a DC power supply; a negative power supply terminal connected to the negative power supply terminal; a first detection electrode connected to the negative power supply terminal; and a second detection electrode connected to the pair of detection electrodes. An ignition means, which is connected to a first output terminal of a discrimination circuit for detecting a current flowing during the interposition of a liquid between the first and the second circuits and which is operated in response to an ignition signal from the discrimination circuit, comprises
In the water landing detection device connected between the second output terminals, a switch means is provided on a bypass line connecting the positive power supply terminal and the second output terminal of the determination circuit, and a counter electromotive force and a DC power supply are provided. The switch means closes and the bypass line is closed when a check signal having a certain polarity and a voltage value that generates a DC power supply voltage is input through the pair of detection electrodes. Water detector. A detection circuit connected to the detection electrode; a DC power supply; and a bypass line connecting a positive power supply terminal of the DC power supply and one of output terminals of the determination circuit. A continuity check device for performing a continuity check of the device by connecting to a detection electrode of the device having a switch means that is closed when the continuity check is performed. (B) The voltage value of the DC power supply provided in the continuity check device is set higher than the voltage value of the DC power supply in the device to be subjected to the continuity check. (C) One of the detection terminals of (a) is connected to a DC power supply in the continuity check device via a switch means in the continuity check device, and a current flowing through the detection terminal is detected. Current-voltage converting means for converting the voltage into a voltage, comparing means for comparing the output voltage of the current-voltage converting means with a reference voltage, and temporarily storing the comparison result from the comparing means, and notifying means accordingly. (D) at the time of continuity check, the positive terminal of the DC power supply in the continuity check device is connected to one of the detection terminals (a) and the detection terminal The negative electrode of the DC power supply in the continuity check device is connected to the positive power supply terminal of the DC power supply in the device to be checked for continuity through the connected detection electrode, (E) the switch means of (c) is connected to the negative side power supply terminal of the DC power supply in the device to be checked for continuity via the other of the terminals and the detection electrode connected to the detection terminal; Switch from start switch When a signal indicating the start of the check operation is received and closed for a predetermined time, one of the detection terminals (a) is connected to the positive terminal of the DC power supply in the continuity check device, and the continuity check is performed. The switch means on the bypass line provided in the device to be closed is closed to close the bypass line. At this time, whether the continuity check is correct or not depends on the magnitude of the current flowing through the continuity check device. The continuity check device.