JP3204417B2 - Gas combustion equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas combustion apparatus, and more particularly to a gas combustion apparatus that automatically adjusts a secondary gas pressure during inspection to a critical secondary pressure.

[0002]

2. Description of the Related Art A current amount calculating means outputs a current calculated from a required combustion amount and a limit voltage consisting of a maximum voltage and a minimum voltage, and a gas proportional valve adjusts a valve opening degree by using the current as an input value to generate a gas. In a gas combustion device which sends a gas of a secondary pressure to a gas burner and burns the gas, the gas secondary pressure is set to a preset maximum limit secondary pressure Pmax in a maximum combustion state or a minimum combustion state (these are called limit combustion states). , Or the minimum critical secondary pressure Pmin (these are referred to as critical secondary pressures).

For this reason, attention is paid to a limit voltage input to a current value calculating means for sending an output current to a gas proportional valve, and each gas is set so that a gas secondary pressure in a limit combustion state becomes a preset limit secondary pressure. An operation of manually adjusting the limit voltage to be input to the current value calculation means is performed for each combustion device.

Referring to FIG. 3, a block diagram of a conventional gas combustion apparatus will be described. , And the combustion of the gas burner 7 is controlled. In order to measure the gas secondary pressure P at the time of inspection and adjustment, the operator sets the manometer to the gas secondary pressure inspection port 30.
The gas secondary pressure P and a preset limit secondary pressure (maximum limit secondary pressure set value Pmax
Alternatively, the operator calculates the deviation of the minimum limit secondary pressure set value Pmin) and sets each connection terminal 33a,
The output voltage of the limit voltage generator 31 is controlled by manually adjusting the respective limit voltage adjustment variable resistors connected to 33b.

At this time, the limit secondary pressure (the maximum limit secondary pressure set value Pmax or the minimum limit secondary pressure set value Pmin) is a common set value for each gas combustion device, and realizes this limit secondary pressure. Limit voltage (maximum limit voltage V)
max or the minimum limit voltage Vmin) is a unique value for each gas combustion device.

[0006]

As described above, in the conventional gas combustion apparatus, most of the adjustment work depends on human beings, so that there is a drawback that human errors occur and the work efficiency of the inspection workers varies. Was left as an issue.

The present invention has been made to solve such problems and disadvantages, and an object of the present invention is to provide a gas combustion apparatus having a structure for automatically performing a gas secondary pressure adjusting operation without manual intervention. is there.

[0008]

According to a first aspect of the present invention, an output current to a gas proportional valve is calculated based on a limit voltage consisting of a predetermined maximum voltage and a minimum voltage. In a gas combustion device that adjusts the degree of opening of a gas proportional valve based on a secondary pressure detector that detects the output pressure of the gas proportional valve, the maximum and minimum values of a predetermined output pressure are set to a limit secondary pressure. Limit voltage that can be calculated by the product of the limit secondary pressure storage unit and the limit secondary pressure
A limit coefficient storage unit for storing a coefficient, a correction means for correcting the limit voltage based on the limit secondary pressure and the output of the secondary pressure detection unit, and a limit combustion mode setting for causing the correction means to execute the limit voltage correction Means, and the correction means is at this limit
The value read from the coefficient storage unit is used as the initial
Limit secondary pressure based on secondary pressure and output of secondary pressure detector
The limit coefficient is corrected so that it converges to the pressure set value.
The limit voltage is calculated based on the product of this corrected value and the limit secondary pressure.
Is calculated .

[0009]

When the maximum combustion state is designated by the limit combustion mode setting means, the signal is given to the correction means. The correction means receives this, reads the maximum limit secondary pressure set value Pmax from the limit secondary pressure storage unit, further sets the maximum limit coefficient αmax read from the limit coefficient storage unit as a convergence initial value, and sets the limit based on the αmax and Pmax. The voltage is calculated, and the limit voltage is input to the current value calculating means. The limit voltage is calculated by, for example, adding or subtracting a constant to / from the product of αmax and Pmax.

The current value calculating means inputs a current calculated based on the limit voltage to the gas proportional valve, and a new gas secondary pressure P corresponding to the gas proportional valve whose valve opening is adjusted according to the current. Is sent to a gas burner and burned. The new gas secondary pressure P generated here is detected by the secondary pressure detecting section and fed back to the correcting means. The correction means is
The maximum limit coefficient αmax is corrected based on the deviation Pmax-P between the current backed gas secondary pressure P and the maximum limit secondary pressure set value Pmax so as to eliminate the deviation, and the corrected α value is set.

[0011] Then it calculates this and corrected α value, a limit voltage based on the product of the maximum limit secondary pressure set value Pmax is a fixed value, and inputs this limit voltage to a current value calculating means.

The current value calculating means inputs the current calculated based on the limit voltage to the gas proportional valve, and the driven gas proportional valve sends a gas of a corresponding new gas secondary pressure P to the gas burner. And burn. On the other hand, the secondary pressure detector detects this new gas secondary pressure P and feeds it to the correction means.
Back.

The feedback loop is repeated in this manner, and when the current gas secondary pressure P converges to the preset maximum limit secondary pressure set value Pmax, α
The correction unit writes and updates the value as the maximum limit coefficient αmax for which correction has been completed, in the limit coefficient storage unit. As described above, the maximum limit coefficient αmax specific to this gas combustion device is
Is automatically corrected and stored.

In the same manner as described above, if the minimum combustion state is designated by the limit combustion mode setting means, the minimum limit coefficient αmin inherent to the gas combustion apparatus is automatically corrected by the same automatic operation. It is stored in the next pressure storage unit 4.

In this gas combustion apparatus, as described above, the limit coefficient (the maximum limit coefficient αmax and the minimum limit coefficient αmin)
Is defined as a value unique to each gas combustion device, and the limit secondary pressure (the maximum limit secondary pressure set value Pmax or the minimum limit secondary pressure set value Pm
in).

[0016] If the change of the limit secondary pressure is needed, because the limit voltage varies greatly with it, but must be re-set at all the new maximum limit voltage Vmax and the minimum limit voltage Vmin as convergence initial value, According to the second aspect of the present invention, the limit coefficient depends on the structure and design of the apparatus, and is hardly affected even when the limit secondary pressure is changed. Therefore, the previous limit coefficient is used as it is as the convergence initial value. be able to.

[0017]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram of the gas combustion apparatus of the present invention. The gas combustion device 1 includes a limit secondary pressure storage unit 4 that stores a maximum limit secondary pressure set value Pmax and a minimum limit secondary pressure set value Pmin, and a limit coefficient storage unit that stores a maximum limit coefficient αmax and a minimum limit coefficient αmin. 3. Gas proportional valve 6
Value calculating means 5 for calculating an output current to the gas, a gas proportional valve 6 controlled by the output current from the current value calculating means 5 to supply combustion gas to the gas burner 7, and a gas secondary valve of the gas proportional valve 6. Based on the secondary pressure detector 8 for automatically detecting the pressure P, the detected gas secondary pressure P and the value read from the limit secondary pressure storage unit 4, a corrected α value is calculated, and based on this α value, A correcting means 10 which calculates a V value as a limit voltage and outputs the calculated value to the current value calculating means 5 and executes reading or writing from the limit coefficient storage unit 3. Further, the correcting means 10 is operated in a maximum combustion state or a minimum combustion state. A limit combustion mode setting means 2 for instructing either of them to correct the α value and update the limit voltage (hereinafter referred to as V value).

The limit secondary pressure storage unit 4 is preset and fixed.
The maximum limit secondary pressure set value Pmax and the minimum limit secondary pressure set value Pmin which are obtained values are stored, and the limit combustion mode setting means 2 stores the maximum limit secondary pressure in the limit secondary pressure storage unit 4. The writing and updating of the set value Pmax and the minimum limit secondary pressure set value Pmin are executed.

The limit coefficient storage unit 3 stores a maximum limit coefficient αmax and a minimum limit coefficient α temporarily stored at the time of factory shipment or the like.
min, and these limit coefficients are updated to new limit coefficients when the adjustment operation is completed.

As shown in FIG. 2, the correction means 10 comprises a gas secondary pressure comparison means 10a, a limit coefficient correction means 10b, and a limit voltage calculation unit 10c. Now, when adjusting the maximum combustion state as an inspection adjustment operation, if the operator designates the maximum combustion state by the limit combustion mode setting means 2, the signal is transmitted to the correction means 10. In response to this, in the correction unit 10, the limit coefficient correction unit 10b reads the maximum limit coefficient αmax from the limit coefficient storage unit 3 as the initial value of convergence, and inputs this as the α value to the limit voltage calculation unit 10c.

Meanwhile, the limit voltage calculation unit 10c limits the combustion mode - receiving a signal from the de-setting means 2 reads the maximum limit secondary pressure set value Pmax from the limit secondary pressure storage unit 4, the limit coefficient correction means 10b The limit voltage obtained by the product of the α value (αmax which is the convergence initial value in this case) and Pmax is sent to the current value calculation means 5.

The current value calculating means 5 inputs the current calculated from the V value to the gas proportional valve 6, and the gas proportional valve 6
The gas is moved to the opening corresponding to the value and the gas of the new gas secondary pressure P is sent to the gas burner 7. Here, the secondary pressure detector 8
The new gas secondary pressure P is detected and fed back to the correction means 10.

The correcting means 10 includes a gas secondary pressure comparing means 1
0a, current gas secondary pressure P and maximum limit secondary pressure set value P
After comparing max, the deviation + dP or -dP is input to the limit coefficient correction means 10b. The limit coefficient correction means 10b
If the current gas secondary pressure P is smaller than the maximum limit secondary pressure set value Pmax, the α value is increased to further increase the opening of the gas proportional valve 6, and the newly corrected α value is limited. It is input to the voltage calculator 10c. Here, the new α value is temporarily stored in the limit coefficient correction unit 10b, but the α coefficient in the limit coefficient storage unit 3 may be rewritten with the new α value each time.

The limit voltage calculation unit 10c calculates a new V value by the product of the newly corrected α value and the maximum limit secondary pressure set value Pmax, and inputs the new V value to the current value calculation means 5.

[0025] The contrast with, if larger than the current gas secondary pressure P is maximum limit secondary pressure set value Pmax, the limit coefficient correcting means 10b is α value to further close the opening of the gas proportional valve 6 And the newly corrected α value is input to the limit voltage calculation unit 10c. The limit voltage calculation unit 10c calculates a new V value by the product of the newly corrected α value and the maximum limit secondary pressure set value Pmax, and inputs the new V value to the current value calculation means 5.

[0026] In repeating the above operation, when the gas secondary pressure P is converged to the maximum limit secondary pressure set Pmax,
The limit coefficient correction unit 10b updates the limit coefficient storage unit 3 with the current α value as a new maximum limit coefficient αmax.

[0027] Next limit combustion mode - even if you specify the minimum combustion state by de setting means 2, can update the minimum limit coefficient αmin as described above.

[0028] during the period from the factory until the time of use in each household by a gas quality conversion, etc., when it becomes necessary to change the maximum limit secondary pressure set value Pmax and the minimum limit secondary pressure value Pmin itself However, it is only necessary to replace the stored value of the limit secondary pressure storage unit 4. When there is no possibility of the above-mentioned gas quality conversion or the like, it goes without saying that the limit voltage may be directly corrected and updated without using the limit coefficient.

The limit combustion mode setting means 2, the current value calculating means 5, and the correcting means 10 are constituted by, for example, a microcomputer and a program. The limit coefficient storage unit 3 and the limit secondary pressure storage unit 4 are configured by a nonvolatile memory such as an EEPROM.

[0030]

As described above, the gas combustion apparatus according to the present invention controls a limit coefficient, and calculates a limit voltage (V value) obtained from the limit coefficient and a preset limit secondary pressure by a current value calculating means. To control the amount of combustion by inputting to the
There is no variation due to the inspection operator, and in addition, the occurrence of human error can be eliminated by automating the adjustment operation.

Further fixed by gas quality conversion etc.
The value is a limit secondary pressure (maximum limit secondary pressure set P
Even when it is necessary to change the max or the minimum limit secondary pressure set value Pmin), it can be used as the initial convergence value without changing the limit coefficient, so that it is not necessary to prepare a new initial convergence value. Therefore, adjustment at the time of gas quality conversion or the like can be easily performed.

[Brief description of the drawings]

FIG. 1 is a block diagram of a gas combustion apparatus according to the present invention.

FIG. 2 is a block diagram of a correction unit in FIG. 1;

FIG. 3 is a block diagram of a conventional gas combustion device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas combustion device 2 Limit combustion mode setting means 3 Limit coefficient storage part 4 Limit secondary pressure storage part 5 Current value calculation means 6 Gas proportional valve 7 Gas burner 8 Secondary pressure detection part 10 Correction means P Gas 2 Secondary pressure αmax Maximum limit coefficient αmin Minimum limit coefficient Pmax Maximum limit secondary pressure set value Pmin Minimum limit secondary pressure set value

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-139353 (JP, A) JP-A-62-155434 (JP, A) JP-A-5-282003 (JP, A) (58) Field (Int. Cl. ⁷ , DB name) F23N 1/00 102

Claims (1)

(57) [Claims] 1. A gas combustion apparatus which calculates an output current to a gas proportional valve based on a limit voltage comprising a predetermined maximum voltage and a minimum voltage, and adjusts an opening degree of the gas proportional valve based on the output current. a secondary pressure detector for detecting the output side pressure of the gas proportional valve, a limit secondary pressure storage unit for storing the maximum and minimum values of the output-side pressure which is predetermined as a limit secondary pressure, the limit two The limit voltage is determined by the product of
Limit coefficient storage unit for storing limit coefficients that can be calculated by
Comprising a correction means for correcting the limit voltage based serial limit secondary pressure as an output of the secondary pressure detector, the limit combustion mode setting means for executing a correction of the limit voltage to the correction means, the correction means Is read from this limit coefficient storage unit.
The critical secondary pressure and the secondary pressure
Secondary pressure converges to the limit secondary pressure set value based on the output of the detector
And the corrected coefficient
Calculates the limit voltage based on the product of the value and the limit secondary pressure.
Gas combustion apparatus, characterized in that that.