JPS6314196Y2 - - Google Patents

Description

[Detailed explanation of the idea]

The present invention relates to a ventilation sensor for a blue flame combustor. When a combustion appliance is burned in a tightly closed room, the oxygen concentration decreases over time, and if oxygen becomes insufficient, the combustion appliance will undergo incomplete combustion, and the exhaust gas will contain incombustible gas and other gases. The increase in carbon monoxide created a dangerous atmosphere that was physiologically harmful and could even lead to death. Currently, semiconductors (metal oxides) and catalytic combustion methods have been proposed as detection means, but these are all highly concentrated gases (target: flammable gas, CO).
In addition, in low concentration gas detection, secondary factors (cigarette smoke, alcohol, humidity,
It had the disadvantage of being prone to malfunction due to changes in voltage (voltage changes), etc. Furthermore, when using these as ventilation sensors for combustors, there are problems such as difficulty in obtaining accuracy in low concentration ranges. Other flame rods are capable of automatically extinguishing fires with soft flames when there is a lack of oxygen in strong combustion, but this function is incomplete in weak combustion. As a result of various trials and errors to solve the above problem, the inventor of the present invention found that when the indoor oxygen concentration reaches a level that requires ventilation, the wavelength of the light emitted from the blue flame (combustion flame) is significantly reduced. It was discovered that when the change is converted into the output of the light-receiving element, a clear change can be read compared to that during normal combustion. The present invention has been made based on the above discovery. Hereinafter, a case where the present invention is implemented in a kerosene vaporizing type combustor will be explained with reference to the drawings. FIG. 1 is a front view of a vaporization type combustor, and 1 is a combustor main body equipped with an oil tank 2 on one side. 3
Converts liquid kerosene into vaporized gas using a vaporizer connected to the oil tank 2. Reference numeral 4 denotes a Bunsen-type burner that burns this vaporized gas, where the vaporized gas is burned as a blue flame consisting of an oxidation flame and an oxidation flame 6. 7
is a furnace provided so as to surround a burner 4, and has an exhaust port 8 above. The hot air 9 from the exhaust port 8 is removed by a fan (not shown) provided at the rear of the main body 1.
The hot air is blown to the front of the main body 1. Reference numeral 10 designates a see-through window drilled at a position corresponding to the oxidizing flame 6 of the furnace 7, and a square-shaped element mounting angle 12 is fastened with screws 13 to the outer periphery of the window through a heat insulating material 11. There is. Reference numeral 14 denotes a protective tube that is inserted through and fixed to the angle 12, and a photoelectric conversion element (referred to as a light receiving element) 15 is provided at one end of the protective tube. This protective tube 14 serves to protect the element 15 and also to block light from the outside in order to improve its performance. 16 is a lead wire of the element 15. In addition,
The mounting position (X...height) of the element 15 is set at an appropriate position 10 to 50 mm from the burner surface, but the optimum position may be selected in relation to the blue flame. Next, its operation will be explained. Now, when combustion starts from a dense and oxygen-rich state, the combustion flame of the burner forms a reducing flame and an oxidizing flame, and complete combustion occurs with a blue flame. However, as time passes and oxygen becomes insufficient, the reducing flame 5 becomes an elongated flame, and the blue flame of the conventional oxidizing flame 6 begins to show signs of red flame. For example, the relationship between oxygen content and combustion flame is shown in the table below. That is, when the oxygen concentration falls below 18%, the oxidation flame 6 becomes almost completely red flame, showing signs of oxygen deficiency. From this point on, the amount of nonflammable gas and carbon monoxide increases.

[Other Examples]

(1) As long as it is a blue flame type combustor, it can be used for oil, gas, or any combustor that uses those fuels. (2) In addition to lighting the LED, the output of comparator IC2 can also sound a buzzer, turn on a ventilation fan, and automatically extinguish a fire. As described above, according to the present invention, when a blue flame type combustor is used, the necessity of ventilation can be accurately detected and notified. Therefore, a decrease in combustion efficiency and an oxygen deficiency accident can be prevented.

[Brief explanation of the drawing]

Fig. 1...Front explanatory view of one embodiment of the present invention, Fig. 2
Fig. 3 is a circuit diagram of its main parts, and Fig. 3 is a characteristic diagram showing the relationship between combustion time, oxygen concentration, and electromotive force of the light receiving element (strong combustion). Figure 4... is a characteristic diagram during weak combustion as well. Code, 6: Oxidation flame, 15: Photodetector, IC1,
IC2: Comparator, LED: Light emitting diode.

Claims (1)

[Scope of Claim for Utility Model Registration] In a combustor equipped with a burner that uses blue flame as the combustion flame, a light receiving device located at a position to receive light from the blue flame and whose electromotive force changes depending on the wavelength of the light. a filter means for extracting only the amplitude of a frequency component higher than a predetermined frequency from the output of the light receiving element; a detection means for detecting that the extracted amplitude is equal to or higher than a predetermined value and outputting it as a pulse output; A combustor ventilation sensor comprising: detection means for detecting that the pulse output of the means continues for a predetermined period of time at a cycle shorter than a predetermined cycle;