JP2875377B2 - Malfunction prevention method during pilot burner combustion - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for preventing malfunctions during combustion of a pilot burner.

(Prior Art) In general, in a combustion device installed indoors, complete combustion is an indispensable element for safety. For this reason, it is necessary to eliminate combustion products and supply fresh air smoothly. Is a condition.

For example, in the bath kettle which has been used conventionally,
As shown in FIG. 4, the air for combustion is taken indoors, and the exhaust gas is discharged from the exhaust pipe by using the natural draft. Therefore, the exhaust pipe is made so that the intake and exhaust are performed smoothly. , And vents are designed.

By the way, in recent years, the airtightness of the house has advanced, and for some reason, the indoor pressure may be lower than that of the outdoor and negative pressure, and the outside air may flow into the combustion section through the exhaust pipe. In order to prevent the flame from being blown out, a backwind prevention unit is provided to allow the outside air to escape indoors. While this backwind prevention unit can release outside air indoors, the burned exhaust gas may overflow into the bathroom and contaminate the air in the bathroom. And monitoring the temperature in the vicinity thereof, shuts off the fuel supply, and stops the combustion.

(Problems to be Solved by the Invention) However, the means for monitoring the temperature in the vicinity of the backwind prevention portion and the vicinity thereof is effective at the time of normal combustion, that is, at the time of combustion of the main burner. At the time of combustion, the influence of combustion is small in and near the backwind prevention part, and therefore,
The determination that the exhaust gas is flowing back into the room becomes unstable, and there is a possibility that a malfunction such as unnecessary stopping of the combustion may be performed.

An object of the present invention has been made in view of the above points, and an object of the present invention is to provide a method for preventing a malfunction at the time of burning a pilot burner.

(Means for Solving the Problems) In order to solve the above-described problems, the present invention prevents external air flowing backward from outside between the combustion appliance body and the exhaust pipe from flowing into the combustion appliance body. A first temperature-sensitive means provided in the backwind prevention section and a second temperature-sensitive means provided in the vicinity of the backflow outflow section of the backwind prevention section. The first temperature sensing means detects the temperature in a state in which a certain temperature is added in advance when monitoring the outflow of exhaust gas indoors by comparing and judging the temperature of the headwind prevention part and the temperature near the headwind outflow part based on the means. Thus, when the pilot burner is burning, a malfunction caused by a small temperature difference between the backwind prevention section and the vicinity of the backflow outflow section and the fluctuation is prevented.

Further, in the combustion device according to the present invention, when monitoring the indoor outflow of exhaust gas, a comparison judgment is made based on a value obtained by adding a predetermined value to the difference between the detection signal by the first temperature sensitive means and the detection signal by the second temperature sensitive means. To prevent a malfunction due to a small temperature difference between the backwind prevention section and the vicinity of the backflow outflow section and the fluctuation during combustion of the pilot burner.

Further, in the combustion device according to the present invention, the temperature of the backwind prevention unit is determined based on the first thermistor provided in the backwind prevention unit and the second thermistor provided in the vicinity of the ventilation outlet of the backwind prevention unit. When monitoring the indoor outflow of exhaust gas by comparing and judging the temperature in the vicinity of the headwind outlet, the first thermistor detects the temperature in advance in consideration of the temperature which becomes large at a low temperature and becomes smaller as the temperature becomes higher. At this time, a malfunction due to a small temperature difference between the backwind prevention portion and the vicinity of the backflow outflow portion and a variation is prevented.

Further, in the combustion device according to the present invention, when monitoring the indoor outflow of exhaust gas, a value obtained by adding a value that becomes larger at low temperatures and becomes smaller as the temperature becomes higher as the difference between the detection signal by the first thermistor and the detection signal by the second thermistor is added. And a comparison judgment is made on the basis of a small temperature difference between the backwind prevention portion and the vicinity of the blow-out portion and a malfunction caused by the fluctuation during the combustion of the pilot burner.

(Operation) In the combustion apparatus, when the exhaust gas is normally discharged during normal combustion, the exhaust gas is discharged to the outside via the backwind prevention unit and the exhaust stack. Since the exhaust gas passes near the first temperature sensitive means, the detection signal of the first temperature sensitive means is larger than the detection signal of the second temperature sensitive means.

During the normal combustion, the operation in the abnormal state is performed as follows.

Now, when the indoor pressure is lower than the outdoor pressure and becomes negative pressure, the outside air flows in from the exhaust stack, flows out indoors through the headwind outflow part of the headwind prevention unit, and the exhaust gas is indoors together with the outside air. Leaked to For this reason, the temperature in the vicinity of the first temperature responsive means is equal to the temperature in the vicinity of the second temperature responsive means in the backward wind outlet, or the temperature of the latter is higher. Such a state is determined as an abnormal state, and when the time in the abnormal state reaches a predetermined time, the supply of fuel is cut off and the combustion is immediately stopped.

By the way, when only the pilot burner is burning, the temperatures at the backwind prevention section and the backflow outflow section are both lower than in normal combustion, and the difference is unclear as compared with that in normal combustion. Although it is difficult to make a comparison as described above, the first temperature sensing means is configured to detect the temperature in a state in which a constant temperature is added in advance, and the apparent temperature near the first temperature sensing means and the vicinity of the second temperature sensing means are detected. Since the temperature difference is clarified, it is possible to avoid a malfunction in which the level of the actual temperature slightly reverses and the supply of fuel is shut off as an abnormal state. In the case where the temperature sensing means is a thermistor, the first thermistor in the backwind prevention unit is configured to detect the temperature in advance with a low temperature and a high temperature taking into consideration a small temperature. By clarifying the apparent temperature difference in the vicinity especially at low temperatures,
Can be achieved. This means that, in other words, even when the exhaust gas flows backward, there is no risk of contaminating the air in the bathroom when only the pilot burner is burning. Since the stop of combustion can be avoided, it is easy to use.

Also, when the exhaust stack is closed for any reason, during normal combustion, the exhaust gas is shut off the exhaust passage, through the ventilation outlet, flows out indoors, the exhaust gas first,
Since it stays near the exhaust stack and near the backwind prevention portion and flows out of the headwind outlet into the room, the temperature near the headwind outlet exceeds a predetermined temperature. Also in this case, at the time of the combustion of the pilot burner, the temperatures near the first temperature responsive means and near the second temperature responsive means do not exceed the predetermined temperature, and erroneous operation can be prevented by the above means.

In order to prevent malfunction as described above, a comparison judgment is made based on a value obtained by adding a predetermined value to the difference between the detection signal by the first temperature sensitive means and the detection signal by the second temperature sensitive means when the pilot burner is burning. It may be. In addition,
When the temperature responsive means is a thermistor, a comparison is made based on a value obtained by adding a value obtained by adding a value that becomes larger at low temperatures and becomes smaller as the temperature becomes higher at low temperatures, to the difference between the detection signals of the first thermistor and the second thermistor.

(Embodiment) Next, an embodiment of a combustion apparatus for carrying out a method for preventing malfunction during combustion of a pilot burner according to the present invention will be described with reference to the accompanying drawings.

In FIG. 1, reference numeral 1 denotes a combustion device, that is, a bath device. The bath device 1 includes a bath kettle 2 serving as a main body of a combustion device installed indoors, and a combustion device 3 built in the bath pot 2. And a backwind prevention unit 6 interposed between the primary exhaust tube 4 and the secondary exhaust tube 5 for discharging exhaust gas from the outside to the outside.

The bath kettle 2 includes a main burner 7 for heating the combustion apparatus 3 and a gas cock 8. Gas cock 8
By operating the ignition knob 9, the pilot burner 10 is ignited to open the solenoid valve 11, and fuel gas is supplied to the main burner 7 to perform combustion.

The primary exhaust stack 4 is mounted on the combustion device 3,
The secondary exhaust pipe 5 projects from indoors to outdoors.

The backwind prevention section 6 is provided with a backflow outflow section 12 opened between the primary exhaust pipe 4 and a baffle plate 13 at an intermediate portion. In the headwind prevention unit 6, a first temperature sensor 14 which is a temperature sensing means for detecting the temperature of the exhaust gas is provided above the baffle plate 13, and the temperature of the outside air or the exhaust gas flowing indoors near the headwind outlet 12 is provided. Is provided with a second temperature sensor 15 for detecting the temperature. The first temperature sensor 14 is set so as to detect a temperature in a state where a certain temperature is added in advance. In this case, when the thermistors are applied to the first and second temperature sensors 14 and 15, a temperature that becomes large at a low temperature and becomes small as the temperature becomes high (for example, 5 ° C. at 20 ° C. and 0.6 ° C. at 100 ° C.) is determined in advance by the temperature characteristics of the thermistors. (° C.) is set to detect the temperature. The temperature responsive means may be any conventional sensor such as a bimetal, a temperature fuse, etc., in addition to a temperature sensor such as a thermistor.

The bath apparatus 1 includes a first temperature sensor 14 (not shown).
And the detection signal from the second temperature sensor 15 is taken in, and the temperature in the vicinity of the backflow prevention unit 6 and the temperature in the vicinity of the backflow outflow unit 12 is compared. Control means is provided for monitoring the outflow of exhaust gas indoors by judging whether or not the temperature exceeds a predetermined temperature, and turning off the electric circuit of the solenoid valve 11 when the exhaust gas is in the indoor outflow state. Note that the predetermined temperature is determined by the combustion performance of the combustion device 3 and obtained by measurement.

In other words, the control means compares the detection signals from the first temperature sensor 14 and the second temperature sensor 15 and determines that (the detection signal from the first temperature sensor 14) ≦ (the detection signal from the second temperature sensor 15), The temperature near the backwind outlet 12 is monitored by the second temperature sensor 15, and if the temperature exceeds a predetermined temperature, an abnormal state is set. The circuit is turned off, and an operation is performed to cut off the supply of the fuel gas.

Further, the control means performs an operation to turn off the electric circuit of the solenoid valve 11 and cut off the supply of the fuel gas when the time in the abnormal state reaches a predetermined time cumulatively within a certain time. Things.

Next, the operation of the bath apparatus 1 having such a configuration will be described.

During normal combustion, that is, when the main burner 7 is burning, when the bath apparatus 1 is in a normal state, exhaust gas generated by the combustion of the main burner 7 flows from the primary exhaust pipe 4 through the baffle plate 13 of the backwind prevention unit 6. The exhaust gas reaches the secondary exhaust stack 5 and is discharged outside. Therefore, the vicinity of the first temperature sensor 14 is a reverse wind outlet.
The temperature of the exhaust gas from the vicinity of 12 and the temperature of the exhaust gas detected by the first temperature sensor 14 is greater than the signal detected by the second temperature sensor 15 (see FIG. 1).

During the normal combustion, the operation in the abnormal state is performed as follows.

When the indoor pressure becomes lower than the outdoor pressure and becomes negative pressure, the outside air flows out of the backflow prevention unit 6 through the secondary exhaust pipe 5 into the room, and the exhaust gas flows out of the room. (See FIG. 2). For this reason, the temperature near the first temperature sensor 14 and the temperature near the second temperature sensor 15 in the backward wind outlet 12 are equal or the latter is higher. The control means (not shown) sets such a state as an abnormal state, and when the time in the abnormal state reaches a predetermined time, turns off the electric circuit of the solenoid valve 11 to cut off the supply of the fuel gas. Thus, the burning of the burning appliance 3 is immediately stopped.

By the way, when only the pilot burner 10 is burning, the temperatures in the backwind prevention section 6 and the backflow outflow section 12 are both lower than in the normal combustion, and the difference in the temperatures is less than that in the normal combustion. Although it is clear and it is difficult to make a comparison as described above, the first temperature sensor 14 is configured to detect a temperature in a state in which a certain temperature is added in advance, and the first temperature sensor 14 and the second temperature sensor 15 Since the temperature difference in the vicinity has been clarified, it is possible to avoid an erroneous operation in which the level of the actual temperature slightly reverses and the supply of fuel is interrupted as an abnormal state. In the case where the first and second temperature sensors 14 and 15 are thermistors, the first thermistor in the backwind prevention unit 6 is configured to detect the temperature in advance in a state where the temperature becomes large at a low temperature and the small temperature is added when the temperature becomes large. , Back wind prevention part 6
This can be achieved by clarifying the apparent temperature difference in the vicinity of the reverse wind outlet section 12 particularly at low temperatures. This means that, in other words, even when the exhaust gas flows backward, there is no possibility that the exhaust gas due to combustion of the pilot burner 10 alone will contaminate the air in the bathroom, so that there is an apparent temperature difference as described above, Unnecessary combustion stoppage can be avoided, so that it is easy to use.

As shown in FIG. 3, when the secondary exhaust pipe 5 is closed for some reason, during normal combustion, the exhaust gas flows indoors via the backward wind outlet section 12 due to the discharge path being shut off. In this case, the exhaust gas first stays in the vicinity of the secondary exhaust pipe 5 and the backwind prevention unit 6 and flows out of the backflow outflow unit 12 indoors. Also in this case, when the pilot burner 10 is burning, the first
The temperature in the vicinity of the temperature sensor 14 and the temperature in the vicinity of the second temperature sensor 15 do not exceed a predetermined temperature, and erroneous operation can be prevented by the above-described means.

To prevent malfunction as described above, use a pilot burner
At 10 combustion, the comparison judgment may be performed based on a value obtained by adding a predetermined value to the difference between the detection signal from the first temperature sensor 14 and the detection signal from the second temperature sensor 15. In the case where the temperature sensor is a thermistor, a comparison is made based on a value obtained by adding a value which becomes larger at low temperatures and becomes smaller as the temperature becomes higher, to the difference between the detection signals obtained by the first thermistor and the second thermistor.

(Effects of the Invention) As described above, according to the present invention, the first temperature responsive means is in a state in which a constant temperature is added in advance (when the temperature responsive means is a thermistor, the temperature is low and when the temperature becomes large, a small temperature is added. ) The temperature is detected, and the apparent temperature difference between the vicinity of the first temperature responsive means and the vicinity of the second temperature responsive means is clarified. Can be avoided. In other words, even if the exhaust gas flows backward, there is no possibility that the exhaust gas due to the combustion of the pilot burner alone will contaminate the air in the bathroom. The necessary stop of combustion can be avoided, so that it is easy to use.

[Brief description of the drawings]

FIG. 1 is an overall explanatory view showing an embodiment of a bath apparatus for carrying out a method for preventing malfunction during combustion of a pilot burner according to the present invention, and FIGS. 2 and 3 show the operation of the bath apparatus shown in FIG. FIG. 4 is an overall explanatory view of a conventional bath apparatus. 1 ... bath apparatus, 2 ... bath pot, 3 ... burning appliances, 4 ...
... Primary exhaust cylinder, 5 ... Secondary exhaust cylinder, 6 ... Backwind prevention part,
7 ... Main burner, 8 ... Gas cock, 9 ... Ignition knob, 10 ... Pilot burner, 11 ... Solenoid valve, 12 ...
Headwind outflow section, 13 baffle plate, 14 first temperature sensor, 15
.... 2nd temperature sensor

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F23N 5/24 104 F23L 17/00

Claims (4)

(57) [Claims] 1. An indoor installation type combustion device having a backwind preventing portion formed between a combustion appliance main body and an exhaust stack to prevent outside air flowing backward from outside from flowing into the combustion appliance body. Based on the first temperature responsive means provided in the prevention unit and the second temperature responsive means provided in the vicinity of the backflow outflow unit of the backwind prevention unit, the temperature of the backwind prevention unit and the temperature in the vicinity of the backwind outflow unit are reduced. When comparing and judging and monitoring the indoor outflow of exhaust gas, the first temperature sensing means is configured to detect the temperature in a state in which a certain temperature is added in advance, and during combustion of the pilot burner, the first wind sensor is connected between the backwind prevention section and the vicinity of the backflow outflow section. A malfunction preventing method at the time of pilot burner combustion characterized by preventing malfunction caused by a small temperature difference and fluctuation. 2. A combustion apparatus according to claim 1, wherein when monitoring the indoor outflow of exhaust gas, a value obtained by adding a predetermined value to a difference between a detection signal by the first temperature sensitive means and a detection signal by the second temperature sensitive means. Erroneous operation during pilot burner combustion, characterized in that when the pilot burner is burning, the temperature difference between the backwind prevention section and the vicinity of the backflow outflow section is prevented and the malfunction caused by the fluctuation is prevented. Method. 3. A combustion device according to claim 1, wherein a first thermistor provided in said backwind prevention portion and a second thermistor provided in the vicinity of a ventilation outlet of said backwind prevention portion are provided. When monitoring the temperature of the prevention unit and the temperature in the vicinity of the headwind outflow unit and monitoring the indoor outflow of exhaust gas, the first thermistor detects the temperature in a state in which the lower the temperature, the higher the temperature, and the lower the temperature, the lower the temperature. A malfunction preventing method during combustion of a pilot burner, wherein a malfunction caused by a small temperature difference between the backwind prevention portion and the vicinity of the backflow outflow portion and fluctuation is prevented during the combustion of the pilot burner. 4. A combustion apparatus according to claim 3, wherein when monitoring the indoor outflow of exhaust gas, the difference between the detection signal by the first thermistor and the detection signal by the second thermistor becomes smaller at a lower temperature and becomes smaller as the temperature becomes higher. The pilot burner performs a comparison judgment based on the value to which the value is added, and prevents a malfunction caused by a small temperature difference between the backwind prevention unit and the vicinity of the ventilation outlet when the pilot burner is burning. How to prevent malfunction during combustion.