JP2729103B2 - Combustion equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a combustion apparatus, and more particularly, to a fan that ventilates combustion air to a combustion section, and a ventilator having one end connected to a discharge side or a suction side of the fan. A sensor for detecting a differential pressure state between an upstream portion and a downstream portion of the road, fan adjustment means for adjusting the output of the fan so that the output value of the sensor becomes a set value, and the sensor output set value. The present invention relates to a combustion device including an air-fuel ratio adjusting unit that changes according to a combustion amount.

[Conventional technology]

FIG. 4 shows a conventional apparatus configuration of a water heater as an example of the above-mentioned combustion apparatus. In the figure, (2) is a fan that blows combustion air to a combustion section (B) where a burner (4) is provided, (11)
Is a ventilation path (F) having one end connected to the discharge side of the fan (2).
In this example, the sensor (11) receives the supply of combustion air from the fan (2) upstream of the burner (4). The differential pressure state between the air chamber (8) and the combustion chamber (9) downstream of the burner (4) is to be detected.

(12) is a fan adjusting means for adjusting the output of the fan (2) so that the output value (P) of the sensor (11) becomes the set value (Ps), and (13) is a sensor output set value (Ps). Air-fuel ratio adjusting means for changing according to the amount of combustion (I), (7) means for adjusting the gas proportional valve (6) to change and adjust the amount of combustion (I), (5) fin tube type Is a heat exchanger for heating water.

That is, in this type of combustion apparatus, clogging of the ventilation path (F) that causes insufficient ventilation of combustion air to the combustion section (B) (for example, fin clogging in the water heating heat exchanger (5)). Even if the influence of the outside air on the end opening of the ventilation path (F) (for example, the application of the outside air pressure to the exhaust opening of the ventilation path (F) in the water heater) occurs, the sensor (1
The output value (P) of 1) is changed to a set value (P) corresponding to the combustion amount (I).
s) (that is, to maintain the differential pressure state at the sensor detection target points (8) and (9) at a differential pressure state corresponding to the combustion amount (I)). Is automatically adjusted to maintain the ventilation amount (Q) of the combustion air to the combustion portion (B) at an amount suitable for the combustion amount (I), whereby the clogging of the ventilation passage (F) and the ventilation In order to prevent the occurrence of poor combustion due to insufficient ventilation of combustion air due to the influence of outside air on the end opening of the road (F) (for example, Japanese Utility Model Laid-Open No. 63-148048, JP-A-63-204018).

[Problems to be solved by the invention]

However, in the conventional device configuration (see FIG. 4), the sensor (11) for the detection target portion (9) on the side farther from the fan (2) among the detection target portions (8) and (9) of the sensor (11). If a leak occurs on the pressure guiding path (10b) of the above or on the road wall (9a) of the detection target point (9) itself on the far side, the three detection target points (8) and (9) and the outside Due to the pressure balance of the sensor (11), both detection target locations (8),
An erroneous detection state is detected in which a differential pressure larger than the actual differential pressure during (9) is detected.

Then, in response to the erroneous detection, the fan adjusting means (12)
Changes the sensor output value (P) (erroneous detection value) to a set value (P) corresponding to the combustion amount (I) specified by the air-fuel ratio adjusting means (13).
As a result of changing the output of the fan (2) to the lower side in order to adjust to (s), the amount of ventilation (Q) of the combustion air to the combustion part (B) matches the amount of combustion (I) at that time. Therefore, there is a problem that poor combustion occurs due to an insufficient amount of ventilation air for combustion.

An object of the present invention is to solve the above-described problem by determining the above-described sensor erroneous detection using a rational determination form.

[Means for solving the problem]

A first characteristic configuration of the combustion device according to the present invention includes: a fan that ventilates combustion air to a combustion section; and an upstream side and a downstream side in a ventilation path having one end connected to a discharge side or a suction side of the fan. A sensor for detecting a differential pressure state; a fan adjusting means for adjusting an output of the fan so that an output value of the sensor becomes a set value; and an air-fuel ratio adjusting means for changing the sensor output set value according to a combustion amount. And a combustion apparatus comprising: an actual value determination unit that determines an actual value of a fan state value that changes according to the output of the fan; and a setting reference correlation between the fan state value and the sensor output value. A reference value determination unit that determines a reference fan state value corresponding to the sensor output set value; and an actual value of the fan state value determined by the actual value determination unit is determined by the reference value determination unit. Based on the fact that the fan output reduction side than the reference fan state value,
And a safety control command means for executing a predetermined safety control. The operation and effect are as follows.

[Action]

That is, (see FIG. 1 and FIG. 3), a fan state value (V) that changes according to the output of the fan (2) is selected, and the sensors (8) and (9) for the sensor detection target portions (8) and (9) are selected. 11) Fan output change under normal conditions with no leaks in the impulse lines (10a) and (10b) and the detection target points (8) and (9) on the respective road walls (8a) and (9a) Focusing on the correlation (L), which is a reference between the fan state value (V) and the sensor output value (P), the fan adjustment means (12) can detect the sensor as long as the operation is performed under the normal state. In adjusting the output of the fan (2) so that the output value (P) becomes the set value (Ps) by the air-fuel ratio adjusting means (13),
The actual value (Vt) of the fan state value (V) determined by the actual value determination means (14) is equal to the reference fan state value (Vs) determined by the reference value determination means (15) (that is, the above reference correlation). In the relationship (L), the fan output is not lower than the fan output value (the fan status value corresponding to the sensor output set value (P)).

However, among the sensor detection target locations (8) and (9), the pressure guiding path (10b) of the sensor (11) to the detection target location (9) on the side farther from the fan (2) and the detection target location on the far side thereof (9) A leak occurs on the road wall (9a) itself,
If the sensor (11) enters an erroneous detection state of detecting a differential pressure larger than the actual differential pressure between the two detection target portions (8) and (9), the fan adjustment means (12) responds to the erroneous detection. The sensor output value (P) (erroneous detection value) to the air-fuel ratio adjusting means (13)
The actual value (Vt) of the fan state value (V) determined by the actual value determination means (14) is changed to adjust the output of the fan (2) to the lower side in order to adjust the output value to the set value (Ps). The fan output is shifted to a lower side than the reference fan state value (Vs) determined by the reference value determination means (15).

That is, according to the first characteristic configuration, the actual value (Vt) of the fan state value (V) determined by the actual value determining means (14) is determined by the reference value determining means (15). By shifting to the fan output lower side than the reference fan state value (Vs), the pressure guide path (10) of the sensor (11) to the detection target point (9) farther from the fan (2).
b) or erroneous detection of a sensor due to a leak on the road wall (9a) of the detection target portion (9) itself on the far side can be determined, and a predetermined safety control can be executed based on this determination. .

[Effect of the invention]

As a result of the above operation, the user does not notice the sensor pressure guide path to the detection target location farther from the fan, or the sensor erroneous detection due to the leak on the road wall of the detection target location itself farther from the fan. It is possible to prevent a situation in which poor combustion occurs and the poor combustion state is continued, and as a result, it is possible to prevent the occurrence of poor combustion due to clogging of the ventilation passage or the influence of outside air on the end opening of the ventilation passage. Combined with this safety function, the safety of this type of combustion device can be greatly improved.

[Second characteristic configuration of the present invention] In a second characteristic configuration of the combustion apparatus according to the present invention, the safety control command means is provided with an actual value of a fan state value determined by the actual value determining means. The present invention is configured to instruct the execution of the safety control when the state on the fan output lower side than the state value continues for a predetermined time or more.

That is, if the second characteristic configuration is adopted, the temporary influence of the external wind on the end opening of the ventilation path (F) and the combustion even if the sensor (11) is in the normal state and the sensor (11) is in the appropriate detection state. The actual value (Vt) of the fan state value (V) is temporarily lower than the reference fan state value (Vs) due to disturbance factors such as a transient phenomenon when the fan output is changed due to the change of the fan output. Unnecessary execution of the safety control can be avoided even before the shift, so that the operation of the device can be stabilized.

〔Example〕

 Next, an embodiment will be described.

FIG. 1 shows a device configuration of a water heater, and a cylindrical case (1).
The discharge side of the fan (2) is connected to one end of the fan, and the exhaust path (3) is connected to the other end, so that a series of ventilation paths (F) extending from the fan (2) to the outlet of the exhaust path (3) are connected. It is formed.

A gas burner (4) is mounted on the fan connection side of the cylindrical case (1), and a fin tube type water heating heat exchanger (5) is mounted on the exhaust path connection side. ), The combustion air is supplied under pressure to the combustion section (B), which is the section where the gas burner (4) is disposed,
After the exhaust gas from the combustion section (B) contributes to water heating in the heat exchanger (5), it is sent to the outside via the exhaust path (3).

(6) is an electromagnetic proportional valve for adjusting the amount of fuel gas supplied to the gas burner (4), and (7) is a combustion for changing and adjusting the combustion amount by adjusting the current value (I) for the electromagnetic proportional valve (6). It is a quantity adjustment unit.

An air chamber (8) located upstream of the gas burner (4) in the cylindrical case (1) and receiving a supply of combustion air from a fan (2); and a gas burner (4) in the cylindrical case (1). The combustion chamber (9) located downstream of the gas burner (4) and the heat exchanger (5) is connected by a small-diameter communication passage (10) disposed outside the cylindrical case (1). And the communication passage (10) has an airflow (f) in the communication passage caused by a pressure difference between the air chamber (8) and the combustion chamber (9).
It is equipped with a current meter (11) for detecting the flow velocity.

In other words, when performing the so-called air-fuel ratio control for adjusting the output of the fan (2) so as to maintain the combustion air flow rate (Q) to the combustion section (B) to an amount suitable for the combustion rate, (11) is used as a sensor for detecting the state of the differential pressure between the air chamber (8) and the combustion chamber (9), and the two chambers (8), (9) obtained from the flow velocity detected by the current meter (11) are used. The output of the fan (2) is adjusted based on the state of the differential pressure in (2).

Regarding the fan output adjustment, the fan voltage (V) is adjusted so that the output value (P) (hereinafter, referred to as a sensor output value) of the current meter (11) becomes the set value (Ps).
And an air-fuel ratio adjustment unit (12) that changes the sensor output set value (Ps) according to the amount of combustion based on information from the combustion amount adjustment unit (7). 13) is provided, which causes clogging of the fan in the heat exchanger (5), which causes an insufficient amount of ventilation air for combustion to the combustion section (B), and application of external wind pressure to the outlet of the exhaust path (3). Even so, the sensor output value (P) is maintained at a set value (Ps) corresponding to the amount of combustion (that is, the state of the differential pressure between the air chamber (8) and the combustion chamber (9) is adjusted according to the amount of combustion). By adjusting and controlling the output of the fan (2) so as to maintain a differential pressure state, the amount of ventilation (Q) of the combustion air to the combustion part (B) is maintained at an amount suitable for the amount of combustion. ,
In this way, it is possible to prevent the occurrence of poor combustion due to insufficient ventilation of combustion air caused by clogging of the fan in the heat exchanger (5) and application of external wind pressure to the outlet of the exhaust path (3).

Specifically, the air-fuel ratio adjusting unit (13) provides a proportional valve current value (I) (combustion amount) as shown in FIG. In the set correlation (M) between the sensor output value (P) and the sensor output value (P), the sensor output (P) corresponding to the adjustment current value (Is) of the combustion amount adjustment unit (7) is set to the sensor output set value (Ps). ) Is specified for the fan adjustment unit (12).

Furthermore, regarding the fan output adjustment, in addition to the fan adjustment unit (12) and the air-fuel ratio adjustment unit (13), the fan voltage (V) (the output of the fan (2)) adjusted by the fan adjustment unit (12) is adjusted. An actual value determination unit (14) that determines the actual value (Vt) of the fan state value that changes in accordance with this, and the setting criteria for the fan voltage (V) and the sensor output value (P) shown in FIG. A reference value determining unit (15) for determining a reference fan voltage value (Vs) corresponding to the sensor output set value (Ps) by the air-fuel ratio adjusting unit (13) in the correlation (L);
The actual fan voltage value (Vt) determined by the actual value determination unit (14) is smaller (Vt <Vs) than the reference fan voltage value (Vs) determined by the reference value determination unit (15). (That is, the fan output is reduced)
A safety control command section (17) for alarming the alarm section (16) is provided.

Regarding the setting of the reference correlation (L) (see FIG. 3), the air chamber side pressure passage portion (10a) in the initial state before being supplied to the user side and in the communication passage (10) And no leakage in the combustion chamber side pressure passage section (10b), and no leakage in the air chamber (8) and the combustion chamber (9) in the respective chamber walls (8a) and (9a). For a given optimum correlation (Lo) between a fan voltage (V) and a sensor output value (P) with respect to a change in fan output, a state is set in which a predetermined allowable range (h) is given to the fan voltage (V) lower side. In other words, the above-described reference correlation (L) is set as a limit of a range allowable as the above-described normal state due to the relationship between the fan voltage (V) and the sensor output value (P). .

That is, there is no leak in any of the air chamber side pressure passage portion (10a) and the combustion chamber side pressure passage portion (10b) in the communication passage (10), and the air chamber (8) and the combustion chamber (9) As long as the operation is performed in a normal state where there is no leak in the chamber walls (8a) and (9a), the fan adjustment unit (12) changes the sensor output value (P) to the set value (Ps) set by the air-fuel ratio adjustment unit (13). ), The fan voltage actual value (Vt) determined by the actual value determination unit (14) in the output adjustment of the fan (2).
Is in the vicinity of the optimum fan voltage value (Vo) corresponding to the sensor output set value (Ps) in the above-described optimum correlation (Lo), and is determined by the reference value determination unit (15). ) (That is, the limit value acceptable as a normal state).

However, the combustion chamber side pressure passage portion (10b) in the communication passage (10) or the chamber wall (9) of the combustion chamber (9) itself.
A leak occurs in a), the air chamber (8), the combustion chamber (9),
And the sensor output (P) due to the pressure balance of the three external parties
Is in an erroneous detection state (state indicated by (Lx) in FIG. 3) indicating a pressure difference larger than the actual pressure difference between the air chamber (8) and the combustion chamber (9). In order to adjust the sensor output value (P) (erroneous detection value) to the set value (Ps) by the air-fuel ratio adjusting unit (13), the fan adjusting unit (12) changes the fan voltage (V) in the figure to (Vx). Down to the fan (2)
The fan voltage actual value (Vt) determined by the actual value determination means (14) to reduce the output of the reference value determination unit (15)
Is smaller than the above-described reference fan voltage value (Vs).

That is, in the configuration in which the actual value determination unit (14), the reference value determination unit (15), and the safety control command unit (17) are provided, the fan determined by the actual value determination unit (14) as described above. When the actual voltage value (Vt) shifts to the fan output lower side from the reference fan voltage value (Vs) determined by the reference value determination unit (15), the combustion chamber side impulse line in the communication passage (10). Part (10b) and chamber wall (9a) of combustion chamber (9)
In this case, an erroneous detection state caused by the leak is determined, and an alarm unit (16) is activated in response to the erroneous detection state.
Due to the adjustment of the fan output to the lower side according to 2), the ventilation amount (Q) of the combustion air to the combustion portion (B) becomes smaller than the amount adapted to the combustion amount, and the user does not notice. This is intended to avoid a situation in which poor combustion occurs and the poor combustion state is unexpectedly continued.

In (18), the state where the actual fan voltage value (Vt) determined by the actual value determination unit (14) is smaller than the reference fan voltage value (Vs) has continued for a set time (t) (for example, 30 seconds) or more. At this time, the timer is a timer unit for limiting the command application operation of the safety control command unit (17) so as to give an alarm operation command to the alarm unit (16). By limiting the fan voltage actual value (Vt)
Unnecessary alarm actuation commands are prevented from being temporarily applied to a value that is temporarily lower than the reference fan voltage value (Vs) due to disturbance or the like.

(19) activates the alarm unit (16) when the temperature (T) detected by the temperature detection element (11a) incorporated in the current meter (11) becomes higher than the set temperature (Ts). A temperature system safety command unit that closes the fuel gas shut-off valve (20) and extinguishes the gas burner (4), and the air chamber side pressure path part (10a) in the communication passage (10) is a cylindrical case. When a large leak is generated in the air chamber side impulse path portion (10a) such that the gas flows out of the combustion chamber or a backflow occurs in the communication passage (10), the high-temperature combustion gas flows back from the combustion chamber (9) to the communication passage (10). Thus, the temperature system safety command section (19) is operated.

 (21) in the figure is a rectifying perforated plate.

(Another embodiment)

 Next, another embodiment will be described.

(1) In the above-described embodiment, the current meter (11) was used as a sensor for detecting the state of the differential pressure between the upstream location (8) and the downstream location (9) in the ventilation path (F). Instead, a pressure sensor may be applied.

(2) The ventilation path (F) to be detected by the sensor (11)
One end thereof may be connected to the suction side of the fan (2). For example, in the above-described embodiment, the fan (2) may be disposed on the side of the cylindrical case (1) on which the combustion air is introduced. Instead, it may be arranged on the exhaust path (3) side.

(3) The upstream location (8) and the downstream location (9) in the ventilation path (F) for detecting the differential pressure state by the sensor (11) are the locations where a differential pressure is generated in the ventilation path (F). Any location may be used. For example, in the above-described embodiment, points (a) and (c) in the figure, points (a) and (d)
Points, points (b) and (c), points (b) and (d), and the like may be set as two target positions.

(4) The fan state value (V) that changes according to the output of the fan (2) is not limited to the fan voltage, but includes various state values such as the fan rotation speed and the phase angle in the voltage control of the fan. Can be adopted.

(5) The predetermined safety control instructed by the safety control command means (17) to execute is not limited to an alarm, but may be any type such as automatic digestion and emergency notification.

(6) The variation of the pressure state in the ventilation path (F) is within the set limit range, and the actual value (Vt) of the fan state value (V) determined by the actual value determination means (14) is as described above. Corresponding to the sensor output set value (Ps) in the optimum correlation (Lo) or the second reference correlation separately set on the fan output increase side near the optimum correlation (Lo) as seen in FIG. Based on the satisfaction of two conditions that the fan output value is on the fan output increase side with respect to the fan state value (V), the fan (of the upstream portion (8) and the downstream portion (9) of the sensor detection target) It is determined that a leak has occurred in the pressure guide path (10a) of the sensor (11) with respect to the point (8) closer to the side 2) or in the road wall (8a) itself in the point (8) closer to the side (8). May be additionally provided with a safety control configuration for executing the above safety control.

In other words, the actual value (Vt) of the fan state value (V) determined by the actual value determination means (14) is the optimum correlation (L
o) Or, if the fan output value is higher than the fan state value (V) corresponding to the sensor output set value (Ps) in the second reference correlation, the ventilation path (F)
(For example, fin clogging of the heat exchanger (5) in the above-described embodiment) and the influence of outside air on the end opening of the ventilation passage (F) (for example, the exhaust passage (3) in the above-described embodiment). Is applied to the outlet (10a) of the sensor (11) with respect to the detection target point (8) on the side closer to the fan (2) and the detection target on the closer side as described above. It cannot be determined that the leak has occurred on the road wall (8a) itself at the location (8).

However, when clogging in the ventilation path (F) or the influence of outside air occurs, the pressure state of the ventilation path (F) fluctuates greatly with the clogging, and the two conditions are determined as the determination conditions as described above. The pressure guide path (10) of the sensor (11) to the detection target point (8) closer to the fan (2)
a) and the road wall (8a) at the detection target point (8) on the near side
The leak itself can be accurately determined by itself.

(7) The present invention is not limited to a water heater, but can be applied to various combustion devices including a fan, such as a fan heater and a boiler.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the accompanying drawings.

[Brief description of the drawings]

FIGS. 1 to 3 show an embodiment of the present invention. FIG. 1 is a diagram showing the configuration of a water heater, and FIG. 2 is a proportional valve current value (burning amount).
FIG. 3 is a graph showing a correlation between a fan voltage (fan state value) and a sensor output value. FIG. 4 is a diagram showing the configuration of a water heater apparatus showing a conventional example. (2) ... fan, (8) ... upstream part, (9) ...
Downstream portion, (11) sensor, (12) fan adjustment means, (13) air-fuel ratio adjustment means, (14) actual value judgment means, (15) reference value judgment means, (17) Safety control command means (B) Combustion section (F) Ventilation path
(I): Combustion amount, (P): Sensor output value, (Ps):
... Sensor output setting value, (V) ... Fan status value, (Vt)
... actual value, (Vs) ... reference fan state value, (L) ... set reference correlation, (t) ... predetermined time.

Claims (2)

(57) [Claims] 1. A fan (2) for passing combustion air through a combustion section (B), and an upstream portion (8) in a ventilation path (F) having one end connected to a discharge side or a suction side of the fan (2). ) And a sensor (11) for detecting a differential pressure state between the downstream side (9) and an output of the fan (2) so that an output value (P) of the sensor (11) becomes a set value (Ps). A combustion device comprising: a fan adjustment unit (12) for adjusting; and an air-fuel ratio adjustment unit (13) for changing the sensor output set value (Ps) according to a combustion amount (I). 2) an actual value determining means (14) for determining an actual value (Vt) of the fan state value (V) that changes according to the output of the fan state value (V) and the sensor output value (P)
A reference value determination means (15) for determining a reference fan state value (Vs) corresponding to the sensor output set value (Ps) in the set reference correlation (L) with the actual value determination means (14). Based on the fact that the actual value (Vt) of the fan state value (V) is lower than the reference fan state value (Vs) determined by the reference value determination means (15), the predetermined value is determined. A combustion device provided with safety control command means (17) for executing safety control. 2. A fan state value (V) determined by said safety control command means (17) by said actual value determination means (14).
2. A command is issued to execute safety control when a state in which the actual value of is lower than the reference fan state value (Vs) on the fan output side continues for a predetermined time (t) or more. A combustion device as described.