JPS5844933B2 - Gas Seigiyosouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas control device for maintaining combustion in an optimum state in a forced air supply/exhaust type combustor.

In conventional forced air supply and exhaust type combustion machines, the gas flow rate is initially set, and the air amount is also set according to the gas flow rate.

That is, both the gas flow rate and the air flow rate are initially set and are fixed.

As a result, the gas pressure fluctuates and the gas flow rate changes, the gas volume decreases due to insufficient opening of the gas valve, the combustion air volume changes due to changes in the atmospheric flow conditions around the supply and exhaust ports, etc. The mixing ratio between the amount of gas and the amount of combustion air is no longer optimal due to external conditions.

This may result in incomplete combustion, or conversely, an excessive amount of combustion air may flow, reducing the efficiency of the combustion equipment as a whole.

The present invention detects the amount of combustion air, controls the gas flow rate, and at the same time detects the amount of gas, and feeds back this detection signal to the gas valve to ensure stable combustion even with changes in the gas flow rate and combustion air amount. It was made so that it could be obtained.

Examples thereof will be described below with reference to the accompanying drawings.

In the figure, reference numeral 1 indicates a gas path, which includes a gas cock 3, a gas flow rate control device 11, and a gas burner 2. Gas enters from a gas inlet 4, passes through the gas flow rate control device 11, and is burned in the gas burner 2.

5 shows a combustion air supply/exhaust circuit, and a blower 6 for supply/exhaust
, a combustion chamber I, and an orifice 8 serving as a flow rate detection means. Combustion air enters from the intake port 9 of this supply/exhaust circuit 5, passes through the orifice 8, is combusted in the combustion chamber 7, and becomes exhaust gas by the blower 6. It is released into the atmosphere from the exhaust port 10.

The gas flow rate control device 11 is composed of a valve body portion consisting of a gas valve 12 and a valve seat 13, an air flow responsive diaphragm 14 and a gas flow responsive diaphragm 15 for driving the gas valve 12.

Reference numerals 16 and 17 are a high pressure chamber and a low pressure chamber that communicate with the high pressure section and the low pressure section before and after the orifice 8.

Reference numeral 18 denotes a chamber of the gas flow responsive diaphragm 15 through which the gas injection box to the burner 2 is guided, and the other chamber 19 is open to the atmosphere.

20 represents the force generated in each diaphragm 14, 15 and the valve 12.
21 is a spring adjustment screw.

Next, the operation of the above configuration will be explained.

Combustion air flows from the intake port 9 and passes through the orifice 8.

At this time, the static pressure on the upstream side of the orifice 8 is high, and the static pressure on the downstream side is low.

This static difference causes a rightward force to act on the air flow responsive diaphragm 14 against the force of the spring 20, thereby opening the valve 12.

As a result, the gas flows from the gas inlet 4 to the gas burner 2 and is burned.

The ejection pressure from the gas burner 2 is guided to the high strain chamber 18 of the gas flow responsive diaphragm 15, and a pressure difference is generated between the chamber 19 and one chamber 19 communicating with the gas flow responsive diaphragm 15.

This differential pressure generates a force in the same direction as the force of the spring 20 in the gas flow responsive diaphragm 15, which tends to close the gas valve 12.

That is, it acts as a negative feedback to the air flow responsive diaphragm 14.

Now, if the flow rate of the air supply/exhaust circuit 5 is QA, the differential pressure △PA generated in the air flow responsive diaphragm 14 is △PAOC.
This will be Q2A.

Further, when the flow rate of the gas circuit 1 is QG, the differential pressure ΔPG generated in the gas flow responsive diaphragm 15 is ocQ2o.

Therefore, the opening degree of the gas valve 12 is maintained at a point where ΔPA, ΔPG and the force of the spring 20 are balanced.

According to the above principle, the amount of gas combusted corresponds to the amount of air flowing into the supply/exhaust circuit 5.

Therefore, the ratio between the amount of gas burned and the amount of air is kept at an optimal value, and an optimal combustion state is always maintained.

As can be seen from the above embodiments, the present invention detects the flow rate of air sent from the blower to the combustion chamber with an air flow responsive diaphragm, drives the gas valve of the gas path to the gas burner, and also operates the gas path. , the low positive chamber is connected to the high strain chamber of the gas flow responsive diaphragm that is open to the atmosphere, and the gas container flowing through the gas path toward the gas burner is directly detected and immediately sends a negative feedback signal to the gas valve. Because there is
The response is faster than the one that has an orifice in the gas path and sends negative feedback, and the air-fuel ratio in a part of the burner can be quickly adjusted to the appropriate value, stabilizing combustion, and since there is no orifice in the gas path. The resistance of this gas path is reduced, making it easier to send more gas to the burner.

[Brief explanation of drawings]

The figure is a schematic configuration diagram showing one embodiment of the present invention. 6... Blower, 7... Combustion chamber, 12.
... Gas valve, 14 ... Air flow responsive diaphragm, 15 ... Gas flow responsive diaphragm.

Claims (1)

[Claims] 1 A combustion chamber in which a gas burner is installed, an air flow-responsive diaphragm that generates force according to the air flow rate forced into the combustion chamber by a blower, and a gas path to the gas burner connected to a high pressure chamber. The low pressure chamber is opened to the atmosphere,
It has a gas flow responsive diaphragm that is displaced according to the flow rate of gas flowing through the gas path, and the gas valve provided in the gas path is actuated by the difference l between the two diaphragms to control the gas flow rate. The gas control device further includes a spring that biases the gas valve in a direction to close it via the gas flow responsive diaphragm.