JPH0116933Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to an abnormality detection device used in a combustor.

[Technical background of the invention and its problems]

A combustor, for example, a kerosene stove, has a variety of mechanisms, including a mechanism that detects inclination caused by earthquakes and extinguishes the fire, a mechanism that extinguishes the fire when abnormally overheated, a mechanism that extinguishes the fire when a power outage occurs, and a mechanism that prevents it from reigniting even when the power is restored. It has a safety mechanism.

However, in the conventional type, various safety mechanisms are provided individually and are independent of each other, and therefore an abnormality detection circuit is provided for each, resulting in a complicated configuration.

[Purpose of invention]

This invention was made to solve such problems, and the purpose is to provide an abnormality detection device in a combustor that can be simplified in configuration.

[Summary of the idea]

This idea connects one end of the charge/discharge capacitor to the positive power supply terminal through the first diode in the forward direction, connects it to the positive power supply terminal through the second diode in the forward direction, and then connects it to the ground through the resistor, and connects the other end to the positive power terminal. One or more abnormality detection switches are inserted in series between the connection point between the second diode and the resistor and the positive power supply terminal to detect an abnormality in the combustor and open the switch, and also to control the operation of the combustor. An operating switch for starting the combustion, a delay thermoswitch for opening upon detection of a temperature rise in the combustion section of the combustor, and a transistor that is turned on only when the delay thermoswitch is closed and the operating switch is opened,
A signal that is low level when the transistor is on and high when it is off, and the inverted output from one end of the capacitor are input to the NAND gate, and the NAND gate output is fed back to one end of the capacitor via an impedance element. and an abnormality detection device that sends an abnormality detection output from the NAND gate.

[Example of idea]

Hereinafter, embodiments of this invention will be described with reference to the drawings.

In the figure, 1 is a charging/discharging capacitor, and one end of this capacitor 1 is connected to the +Vc terminal through a first diode 2 in the forward direction, and connected to the ground through a second diode 3 in the forward direction and further through a resistor 4. and the other end is directly grounded. Between the connection point between the second diode 3 and the resistor 4 and the +Vc terminal, there is a seismic switch 5 that opens when the combustor is tilted due to an earthquake, etc., and a superheating thermostat that opens when the combustor overheats abnormally. A series circuit of switch 6 is connected. 7 is an NPN type transistor, and the collector of this transistor 7 is connected to + through a resistor 8.
The emitter is connected to the Vc terminal, the emitter is grounded through the resistor 9, and the +Vc terminal is connected through the operation switch 10 that starts the operation of the combustor, and the base is connected to the resistor 11 and the temperature rise of the combustor is detected. A delay thermoswitch 12 that opens is connected in series to the +Vc terminal. One end of the capacitor 1 is connected to the input terminal of an inverter 14 via a resistor 13, the output terminal of the inverter 14 is connected to one input terminal of a two-input NAND gate 15, and the collector of the transistor 7 is connected to the input terminal of the inverter 14. It is connected to the other input terminal of the NAND gate 15. A resistor 16 as a feedback impedance element is connected between the output terminal of the NAND gate 15 and one end of the capacitor 1.

In the embodiment of the present invention configured as described above, when normal operation is performed, the operation switch 10 is switched on.
is closed, a reverse bias is applied to the base of transistor 7, and transistor 7 is turned off. On the other hand, both the seismic switch 5 and the overheating thermoswitch 6 are closed. Therefore, the output from one end of the charging/discharging capacitor 1 is at a high level. Therefore, the input to one side of the NAND gate 15 becomes low level, the output of the NAND gate 15 becomes high level, and no abnormality detection is performed. If a power outage occurs in this state, the charge in the capacitor 1 is immediately discharged via the first diode 2. Afterwards, when the power outage is restored, transistor 7 is off and the output from one end of capacitor 1 is at a low level.
Both inputs of the NAND gate 15 become high level, and the NAND gate 15 outputs a low level abnormality detection signal S. Further, since the output level of the NAND gate 15 becomes low level, charging of the charging/discharging capacitor 1 is prohibited and this state is locked. In this way, fire extinguishing control and the like are performed based on the abnormality detection signal S. In this state, turn on the operation switch 1.
0 is opened, and when the temperature of the combustor falls and the delay thermoswitch 12 is closed, the transistor 7 is turned on. As a result, the output of the NAND gate 15 becomes high level, and the abnormality detection state is canceled. Also, the charging/discharging capacitor 1 is charged.

When the operation switch 10 is turned on again, the combustion operation is restarted. In addition, while driving, the vibration sensor switch 5
When the overheating thermoswitch 6 or the overheating thermoswitch 6 is opened, the charge in the charging/discharging capacitor 1 is discharged through the second diode 3 and the resistor 4, and one end thereof becomes a low level. As a result, both inputs to the NAND gate 15 become high level, the output becomes low level, and the abnormality detection signal S is output.
At the same time, the low level state of one end of the capacitor 1 is maintained and the abnormality detection state is locked. In this way, even when the seismic switch 5 or the overheating thermoswitch 6 is activated, an abnormality is detected and fire extinguishing control is performed.

In this way, when an abnormality occurs due to a power outage or an abnormality occurs due to the operation of the seismic switch 5 and the overheating thermoswitch 6, the common charging/discharging capacitor 1 is controlled to discharge, the NAND gate 15 outputs the abnormality detection signal S, and the state is monitored. Since it is designed to be locked, abnormality detection due to the occurrence of various abnormalities can be reliably detected with a simple configuration.

In addition, in the above embodiment, a seismic switch and an overheating thermos switch are used as the abnormality detection switch, but the present invention is not limited to these, and various other abnormality detections such as a water contamination detection switch and an oil-out detection switch are used. Switches may also be used, and the number is not limited to two.

[Effect of idea]

As described in detail above, according to this invention, it is possible to provide an abnormality detection device that can realize abnormality detection in the occurrence of a plurality of types of abnormalities with a simple circuit configuration.

[Brief explanation of drawings]

The figure is a circuit diagram showing an embodiment of this invention. DESCRIPTION OF SYMBOLS 1... Charge/discharge capacitor, 2... First diode, 3... Second diode, 4... Resistor, 5
...Seismic switch, 6...Overheating thermoswitch,
7... NPN transistor, 10... Operation switch, 12... Delay thermo switch, 15... NAND gate, 16... Feedback resistor.

Claims (1)

[Scope of utility model registration request] a charging/discharging capacitor having one end connected to a positive power supply terminal through a first diode in the forward direction, and grounded through a second diode in the forward direction and further through a resistor, and the other end being directly grounded; A plurality of abnormality detection switches are inserted in series between the connection point of the second diode and the resistor and the positive power supply terminal to detect an abnormality in the combustor and open the switch, and an operation switch to start operation of the combustor. , a delay thermoswitch that detects and opens the temperature rise in the combustion section of the combustor, a transistor that is turned on only when the delay thermoswitch is closed and the operation switch is opened, and a transistor that is turned on when the transistor is turned on. A NAND gate that receives a signal that becomes a high level during off-operation and an inverted output of the output from one end of the capacitor, and a feedback impedance element that is connected between the output end of the NAND gate and one end of the capacitor. An abnormality detection device in a combustor, characterized in that the abnormality detection device is provided and sends an abnormality detection output from the NAND gate.