JPH1030816A - Safety device against co in combustion equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute safety action against CO, using an estimated indoor CO concentration calculated on a supposition that exhaust gas has leaked into a room and in relation to the CO concentration in the exhaust gas. SOLUTION: A CO sensor 11 is provided on the exhaust side in combustion equipment and detects the CO concentration in the exhaust gas. An estimated indoor CO concentration-calculating part 12 takes the combustion time measured by a combustion time-measuring means 13 and the CO concentration in the exhaust gas detected by the CO sensor 11 and by use of a calculation formula taking into account the cubic capacity of the room estimates the CO concentration in the room on the supposition that the exhaust gas has leaked into the room. When the estimated CO concentration in the room has reached a reference value for judgment indicative of danger given in advance, a CO safety action part 14 executes safety action against CO, such as shutoff of fuel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CO safety device for combustion equipment, such as an indoor water heater, for ensuring safety against carbon monoxide gas.

[0002]

2. Description of the Related Art FIG. 5 shows a schematic structure of a water heater generally known as a combustion device, and FIG. 6 shows a usage mode in which the water heater 1 is installed in a room of a building. ing.

[0003] This type of water heater 1 sends indoor air to a burner 4 through a filter 3 by the rotation of a fan 2 and burns a fuel gas supplied to the burner 4 to heat a heat exchanger 5. The water passing through the heat exchanger 5 is turned into hot water, and hot water is supplied to a desired place such as a kitchen through a hot water supply pipe connected to the outlet of the heat exchanger 5. The combustion operation of the water heater is performed by a control device 6, and a remote control 7 is connected to the control device 6.

When installing this water heater 1 indoors,
The base of the chimney 10 is fitted to and fitted to the exhaust outlet tube 8 of the water heater 1, and the end of the chimney 10 is taken out of the building to take in the indoor air and discharge the exhaust gas burned out of the building. I have to. When the chimney 10 is taken out, as shown in FIG. 6, a wall hole may be opened near the water heater 1 and the tip of the chimney 10 may be protruded out of the wall hole. Depending on the structure, as shown by the broken line, the chimneys 10 are joined together and the ceiling is attached, and the chimney 10
A construction method is also adopted in which the tip of the is projected outside the building.

[0005] When this type of water heater 1 is operated for combustion, if strong wind blows into the exhaust port of the chimney 10, incomplete combustion occurs and carbon monoxide gas (hereinafter referred to as CO gas) is generated. In a state where exhaust gas is completely exhausted through the chimney 10, the effect of CO gas in the room does not occur. However, if a gap is formed at the seam of the chimney 10 or the seam comes off, the (chimney) In the case where 10 is laid on the ceiling, there is a danger that the CO gas flows back into the room (through a gap in the ceiling) and causes CO gas poisoning.

For this reason, in the past, as shown in FIG.
A CO sensor 11 is installed on the exhaust side of the water heater 1 and safety measures such as issuing an alarm when the concentration of CO gas in the exhaust gas reaches a predetermined dangerous concentration or stopping the combustion operation are taken. I was

However, this type of safety measure against CO gas has a problem that as long as the CO gas concentration in the exhaust gas does not reach the dangerous concentration, a safe operation is not performed even if the CO gas leaks into the room. there were.

[0008] In order to solve such a problem, the applicant of the present application has proposed an improved C
O safety device is proposed. This proposed device calculates the amount of CO hemoglobin concentration in blood in which CO gas is taken into blood when assuming that CO gas in exhaust gas leaks into a room and a person in the room is exposed to the CO gas, When this calculated value becomes the value of the danger criterion, the CO safety operation is performed.

[0009]

According to the apparatus proposed by the applicant, even if the CO concentration in the exhaust gas does not reach the dangerous concentration, it is assumed that the exhaust gas has leaked into the room. Since the blood CO hemoglobin concentration is calculated and the safety operation is performed, the reliability of the safety means for the CO gas can be remarkably improved as compared with the former device, but it is momentarily detected by the CO sensor. The calculation formula for calculating the concentration of CO hemoglobin in human blood corresponding to the changing CO concentration in exhaust gas becomes extremely complicated,
In order to perform accurate calculations, a large computer is required.

However, it is extremely difficult to mount such a large-sized computer in the combustion equipment. For this reason, rough data calculated in advance is provided to a memory or the like of a control device in the combustion equipment, and the combustion equipment is provided with such rough data. There has been no choice but to simply calculate the blood CO hemoglobin concentration using a microcomputer, and it has been desired to take more detailed safety measures for the CO concentration.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a CO apparatus for a combustion apparatus capable of performing a fine and highly reliable CO safety operation without requiring a complicated operation. It is to provide a safety device.

[0012]

In order to achieve the above object, the present invention takes the following measures. That is,
According to a first aspect of the present invention, there is provided a combustion device provided with a CO sensor for detecting a CO concentration in exhaust gas on an exhaust side of the combustion device, and performing a CO safety operation based on information on a detected CO concentration detected by the CO sensor. A combustion time measuring means for measuring a combustion time of a combustion device in the CO safety device;
Based on the CO concentration detection value of the sensor, the estimated value of the CO concentration in the room when it is assumed that the exhaust gas has leaked into the room from the start of the combustion of the combustion equipment is calculated by an arithmetic expression given in advance in consideration of the room volume and the combustion time An indoor CO concentration estimating operation unit for calculating, and a CO safety operation unit for performing a safety operation on CO gas when an estimated value of the indoor CO concentration obtained by the CO concentration estimating operation unit reaches a predetermined danger criterion value. This is a means for solving the problem with a configuration having the following.

According to a second aspect of the present invention, a CO sensor for detecting the concentration of CO in the exhaust gas is provided on the exhaust side of the combustion equipment, and a CO safety operation is performed based on information on the detected CO concentration detected by the CO sensor. In a CO safety device of a combustion apparatus that performs the following, when it is assumed that exhaust gas having a constant CO concentration has leaked into a room, the danger arrival time T until the CO concentration in the room reaches a predetermined danger judgment reference value is determined for each exhaust gas. Time conversion data to be obtained corresponding to the CO concentration is given, and the CO concentration in the exhaust gas detected by the CO sensor is taken in units of a sampling time t _SP given in advance after the combustion device starts burning. Exhaust gas CO concentration sampling section and exhaust gas C sampled by the exhaust gas CO concentration sampling section
The danger arrival time T corresponding to the O concentration to calculate the value of t _SP / T seeking the conversion data the time for each sampled integration value of t _SP / T determined for each sampling t _SP / It is a problem to be solved by a configuration having a T calculation integration unit and a CO safety operation unit that performs a safety operation on CO gas when the integrated value of t _SP / T by the t _SP / T calculation integration unit reaches a predetermined set value. Is a means to solve.

[0014] In the invention having the above-described structure, the CO concentration in the exhaust gas is detected by the CO sensor after the combustion of the combustion equipment installed indoors is started. Then, based on the CO concentration in the exhaust gas detected by the CO sensor, in the first invention, the parameters include information on the combustion time of the combustion equipment and the volume of the room assumed to leak the exhaust gas. The estimated value of the CO concentration in the room is obtained by the CO concentration estimating calculation unit using the arithmetic expression. In the second invention, the degree of danger of the CO concentration in the room is t _SP / T.
As a result of performing a safe operation for CO gas when these calculated values reach the danger determination reference value, a highly reliable CO safe operation becomes possible, and an object of the present invention. Problem solving is achieved.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a basic configuration of an embodiment of the present invention.
12, a combustion time measuring unit 13, and a CO safe operation unit 14. In addition, the combustion equipment in which the CO safety device of the present embodiment is mounted includes a single-function water heater (a water heater having only a hot-water supply function), a bath kettle, a combined hot-water supply / bath combination, a heater /
It is intended for indoor-installed combustion devices that perform combustion such as a cooling machine and a heating / cooling device, and the exhaust side of these combustion devices is provided on the exhaust side as in the conventional example shown in FIG. C
A CO sensor 11 for detecting the O concentration is provided. And
Exhaust gas from the combustion equipment is discharged outside (outdoor) through a chimney (duct) 10. Combustion air is of a type that takes in indoor air, or external air is passed through an air intake pipe. Intake type, or type with a double cylindrical exhaust pipe and external air intake pipe
It can take various forms, and is not limited to the type and type of combustion equipment, and is applied as a CO safety device for all types of combustion equipment installed indoors.

The indoor CO concentration estimating calculation unit 12 calculates the CO concentration in the room when it is assumed that the entire amount of the exhaust gas has leaked into the room based on information on the CO concentration in the exhaust gas detected by the CO sensor 11. The combustion time of the device and the volume of the room are obtained by a predetermined arithmetic expression including parameters.

This arithmetic expression is given by the following (1), and this arithmetic expression is stored in a memory or the like inside the arithmetic unit 12 in advance.

C _ROOM = (Q ₃ XC _EXT / nV) {1-exp (−nt)} (1)

In this equation, C _ROOM is the indoor CO concentration (ppm)
), Q ₃ is the total amount of exhaust gas (m ³ / h), X is the ratio of the amount of exhaust gas leaking indoors to the total amount of exhaust gas (total amount),
C _EXT indicates the CO concentration (ppm) in the exhaust gas, n indicates the ventilation rate by a ventilation fan or the like, V indicates the room volume (m ³ ), and t indicates the combustion time. Note that the ventilation rate n is n = Q ₁ / V
Where Q ₁ is the amount of air exhausted by the ventilation fan (m ³ /
h), where Q ₁ is given by the relational expression Q ₁ = Q ₀ + Q ₃ X. Here, Q ₀ is the amount of air flowing into the room (m ³ /
h).

FIG. 4 shows a model diagram of the room relating to the calculation of the equation (1). In the figure, reference numeral 15 denotes an air suction pipe for introducing air from outside to the combustion equipment, and 16
Indicates a defective portion 16 generated in the middle of the chimney 10, and indicates a state in which exhaust gas from the combustion equipment is leaking from the defective portion 16 into the room.

In the above equation (1), Q ₃ , X, n, V
Parameters can be given as known data,
In addition, C _EXT is _detected by the CO sensor 11 as CO
The combustion time t is detected by the combustion time measuring means 13 such as a timer and a clock, and is obtained as a known value. Indoor CO concentration estimation calculation unit
Numeral 12 captures the information on the CO concentration in the exhaust gas detected from the CO sensor 11 and the value of the combustion time t measured by the combustion time measuring means 13, and assumes that the exhaust gas has leaked into the room. _Is calculated. In this calculation, it is assumed that all the exhaust gas has leaked into the room in view of safety and under the condition of X = 1.0, C
_{The ROOM} is calculated, and the calculation result is added to the CO safe operation unit 14.

[0022] CO safe for operation portion 14 is given in advance danger criterion value C _th is, for example, 300 ppm values of indoor CO concentration, CO safe operating unit the risk determination reference value C _th and the indoor CO concentration 14 comparing the calculated by the estimation calculation section 12 value C _ROOM, blocking of the fuel cut-off (valve provided in the gas passage for supplying to the burner to the burner when the value of C _ROOM reaches dangerous criterion value C _th ) To perform a safe operation for CO gas.

In this safe operation for CO, a plurality of danger judgment reference values are provided. For example, when the indoor CO concentration obtained by calculation reaches the danger judgment reference value of the first stage, the rotation of the fan 2 is stopped. To increase the amount of air to improve the burner 4 combustion,
When a value of the indoor CO concentration C _ROOM calculated by the indoor CO concentration estimating calculation unit 12 reaches the second-stage danger criterion value, fuel cutoff is performed. It is possible to perform an operation.

Next, a more specific embodiment of the present invention will be described with reference to FIG. The CO safety device of the embodiment shown in FIG.
, A t _SP / T calculation and integration unit 18, a clock mechanism 20, a data memory 21, and a CO safe operation unit 14. The exhaust gas CO concentration sampling unit 17 provides a CO concentration C _EXT in the exhaust gas from the CO sensor 11 after the start of combustion in units of a predetermined unit sampling time t _SP given in advance.
Is sampled. Specifically, the sampling time is set to, for example, 10 seconds, the detection information of the CO sensor 11 is fetched every second, the average value is obtained, and determined as the value of the CO concentration in the exhaust gas per unit sampling time. . Note that the timing of this sampling is performed based on a signal of the clock mechanism 20 including a timer, a clock, and the like.

The data memory 21 is provided with data relating to the time T and the CO concentration C _EXT in the exhaust gas as shown in FIG. The time T on the vertical axis of this data is the CO concentration C
_{When EXT} exhaust gas leaks into the room, shows the time required for the chamber of the CO concentration C _ROOM reaches a critical criterion value C _th previously given, for example, the exhaust gas CO concentration C _EXT1 This indicates that when the gas leaks into the room, the risk determination reference value C _th (for example, 300 ppm) is reached in the time T _1. Similarly, when the exhaust gas having the CO concentration of C _EXT2 leaks into the room, T ₂ When the time has elapsed,
This indicates that the indoor CO concentration C _ROOM reaches the danger determination reference value C _th .

The graph data shown in FIG. 3 is obtained by calculation or experiment. When calculating by calculation,
By using the above equation (1), t is obtained by substituting C _th into the value of C _ROOM in this (1) and substituting C _EXT1 into the value of C _EXT to obtain t = T ₁ . Similarly, the value of C _EXT is
By substituting the _EXT2, t = T ₂ is obtained. As described above, when it is assumed that the exhaust gas of each constant CO concentration has leaked into the room, the time T at which the indoor CO concentration C _ROOM reaches the danger determination reference value C _th is obtained. The data of FIG. 3 is obtained.

When the data of FIG. 3 is obtained by an experiment, a CO sensor is separately provided in the room. For example, when the exhaust gas having a certain concentration C _EXT1 is leaked into the room, the CO sensor in the room judges the danger. The time T ₁ to reach the reference value C _th was actually measured, and this operation was carried out by changing the CO concentration of the exhaust gas to each CO 2.
By measuring the time T corresponding to the concentration, data as shown in FIG. 3 is obtained, and these data are stored in the data memory 21.

The t _SP / T calculating and integrating section 18 first detects the exhaust gas C
The value of the CO concentration in the exhaust gas detected in units of the unit sampling time t _SP added from the O concentration sampling unit 17 is taken in, and the value of t _SP / T is calculated. here,
T is obtained by using the data shown in FIG. 3 stored in the data memory 21. When it is assumed that the exhaust gas having the CO concentration C _EXT detected by the CO sensor 11 has leaked into the room, T The time T at which the concentration reaches the danger criterion value C _th is obtained by dividing the sampling time t _SP by the time T at which the danger criterion value is reached.
Of the sampling time t _SP with respect to This value of t _SP / T means that the ratio of t _SP / T in the safe time T is spent, leaving only the safe ratio (1−t _SP / T). In other words, of the time T during which the CO concentration in the room reaches the dangerous judgment reference value, t _SP is spent, and the remaining safety time means only T−t _SP time is left. I do.

[0029] t _SP / T calculating integration unit 18, first at the first sampling time, seek t _SP / T, even when the next sampling time, determined by the detection data of the CO concentration in the exhaust gas t _SP / T is calculated, and this calculated value is added to t _SP / T obtained at the previous sampling,
The integrated value is obtained. In this manner, t _SP / T calculating integrating section 18 is determined at each sampling time t _SP /
The value of T is successively integrated for each sampling time.
For example, when t _SP / T ₁ is obtained at the _first sampling time, and when t _SP / T ₂ is obtained at the next sampling time, t _SP / T ₁ + t _SP / T ₂ is obtained as an integrated value.
Is obtained as an integrated value. Further, when the t _SP / T ₃ obtained in the third sampling time, the accumulated value _{t SP (1 / T 1 +} 1 / T 2 + 1 / T 3) , and this way, t _SP / T calculated The integrating unit 18 integrates the value of t _SP / T obtained at each sampling time, and adds the integrated result to the CO safe operation unit 14.

The CO safety operation section 14 is a t _SP / T calculation integration section 18
The integrated CO concentration C _ROOM is determined to have reached the preset danger determination reference value C _th when the integrated value reaches a predetermined set value, for example, 1.0, and CO safety operation such as shutting off gas to the burner 4 is performed.

According to the embodiment of the present invention, when it is assumed that the exhaust gas having the CO concentration detected by the CO sensor has leaked into the room, the CO concentration in the room is obtained by an arithmetic expression in consideration of the room volume. It is what was constituted.

The arithmetic expression for converting and calculating the CO concentration in the exhaust gas into the indoor CO concentration in consideration of the indoor volume can be given in a very simple form, so that the calculation does not require a large computer and the combustion equipment can be used. Sufficiently accurate calculations can be performed using a microcomputer mounted on the computer, thereby enabling fine-grained safe operation for CO gas. Moreover, since the CO safe operation can be performed using the actual value of the indoor CO concentration, the accuracy of the CO safe operation is enhanced, and the reliability of the CO safe operation is also thorough.

The present invention is not limited to the above-described embodiment, but can adopt various embodiments. For example, in the above-described embodiment, the data for obtaining the time T at which the indoor CO concentration reaches the danger determination reference value from the value of the CO concentration in the exhaust gas is in the form of graph data as shown in FIG. It can be provided in a desired form such as table data, arithmetic expression data, and the like.

[0034]

According to the present invention, when it is assumed that the exhaust gas has leaked into the room, C detected in the exhaust gas
An arithmetic expression for obtaining the indoor CO concentration using information on the O concentration is given by an arithmetic expression using the indoor volume and the combustion time as parameters, and the indoor CO concentration is estimated and calculated based on the arithmetic expression. Therefore, it is possible to give an arithmetic expression for calculating the CO concentration in the room using the value of the CO concentration in the exhaust gas in a very simple form.
It does not require a large computer, and can perform accurate calculations using a microcomputer mounted in the combustion equipment.

Further, since the indoor CO concentration is obtained in consideration of the indoor volume, an accurate indoor CO concentration can be obtained regardless of the size of the indoor volume. Since the CO safety operation is performed based on this, the accuracy for the CO safety operation is increased, and the reliability of the safe operation can be significantly increased.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing a more specific embodiment of the present invention.

FIG. 3 is a data showing a relationship between a CO concentration in exhaust gas and a time T required for the CO concentration in the room to reach a dangerous judgment reference value when it is assumed that the exhaust gas having the CO concentration has leaked into the room. is there.

FIG. 4 is an indoor model diagram for deriving an arithmetic expression for obtaining indoor CO concentration.

FIG. 5 is a configuration explanatory view of an indoor-installed type water heater generally known as a combustion device.

FIG. 6 is an explanatory diagram of an example of indoor installation of a combustion device.

[Explanation of symbols]

12 Indoor CO concentration estimation calculation unit 13 Combustion time measurement means 14 CO safety operation unit 17 Exhaust gas CO concentration sampling unit 18 _tSP / T calculation integration unit 21 Data memory

Claims (2)

[Claims] 1. A CO sensor for detecting the concentration of CO in exhaust gas is provided on the exhaust side of the combustion equipment, and the CO of the combustion equipment performs a safety operation based on information on the detected CO concentration detected by the CO sensor. In the safety device, a combustion time measuring means for measuring the combustion time of the combustion equipment;
Based on the CO concentration detection value of the sensor, the estimated value of the CO concentration in the room when it is assumed that the exhaust gas has leaked into the room from the start of the combustion of the combustion equipment is calculated by an arithmetic expression given in advance in consideration of the room volume and the combustion time An indoor CO concentration estimating operation unit for calculating, and a CO safety operation unit for performing a safety operation on CO gas when an estimated value of the indoor CO concentration obtained by the CO concentration estimating operation unit reaches a predetermined danger criterion value. And a CO safety device for combustion equipment having: 2. A CO sensor for detecting the concentration of CO in exhaust gas is provided on the exhaust side of the combustion equipment, and the CO of the combustion equipment performs a safety operation based on information on the detected CO concentration detected by the CO sensor. In the safety device, when it is assumed that exhaust gas with a constant CO concentration leaks into the room, the danger arrival time T until the indoor CO concentration reaches a predetermined danger judgment reference value corresponds to the CO concentration in each exhaust gas. The time conversion data obtained by the calculation is given, and the sampling time t given in advance after the start of combustion of the combustion equipment is given.
_An exhaust gas CO concentration sampling unit that captures the CO concentration in the exhaust gas detected by the CO sensor in units of _SP; and the danger arrival time T corresponding to the exhaust gas CO concentration sampled by the exhaust gas CO concentration sampling unit. Is _{calculated from the} time conversion data to obtain t _SP
And t _SP / T calculation integrating unit the value of the / T integrating the values of t _SP / T obtained for each calculated in each sampling for each sampling, the t _SP / T according to the t _SP / T calculation integration section A CO safety device for a combustion device, comprising: a CO safety operation section that performs a safety operation on CO gas when the integrated value reaches a predetermined set value.