TWI540289B - Combustion control method of gas appliance - Google Patents

Description

Gas appliance control method

The invention relates to the control of gas appliances; in particular to a combustion control method for gas appliances.

According to the heating device using electric energy, the gas appliance has the advantages of energy saving, high thermal efficiency, instant use, etc., and has been widely used in the field of heating. In order to increase the thermal efficiency of gas appliances, gas-powered gas appliances have been introduced.

The gas trap type of the conventional forced air supply type shown in FIG. 1 includes a burner 10, a gas valve 12, a blower 14, a flame sensing needle 16, and a controller 18. The burner 10 is used for burning gas. The gas valve 12 is disposed on a gas line 20 connected to the burner 10. The gas line 20 is connected to a gas source G, and the gas valve 12 is controlled to be supplied and controlled. The amount of gas to the burner 10. The blower 14 is in communication with the combustor 10, which is controlled to regulate the amount of air supplied to the combustor 10. The flame sensing needle 16 is used to sense the flame generated by the burner 10. The controller 18 is electrically connected to the gas valve 12, the blower 14 and the flame sensing needle 16. The controller 18 controls the gas valve 12 and the blower 14 according to a set total heating value to supply a certain proportion of gas volume and air volume to the burner 10 to obtain better combustion efficiency.

However, when the pressure of the gas source G is low, since the amount of air supplied by the blower 14 is maintained, the amount of air will be more than the amount of gas, which will cause the flame outputted by the burner 10 to exhibit "flying fire". Phenomenon, also That is, the flame will be away from the burner 10 when the gas pressure is normal. As the gas source G pressure continues to decrease, the flame will continue to move away from the burner 10, rendering the flame inaccessible to the flame sensing needle 16 (see Figure 2 for reference). In this state, the controller 18 is unable to receive the electrical signal of the flame sensing pin 16, and thus determines that the gas is used for the gas, and the gas valve 12 is controlled to block the gas. However, the gas source G is not actually used by the gas. Only the gas pressure is low. This situation usually occurs when the gas source is liquid drum gas, the gas capacity in the gas barrel is insufficient; or when the gas source is natural gas, too many gas appliances are used at the same time to uniformly distribute the gas pressure at the source.

Taking a gas water heater as an example, if the gas source G pressure is low during the use of hot water, a flying fire phenomenon occurs, causing the controller 18 to block the gas, which will cause the user to fall into the dilemma of no hot water available. Therefore, the design of the conventional mandatory gas supply type gas appliance 1 is still not perfect, and there is still room for improvement.

In view of the above, the object of the present invention is to provide a combustion control method for a gas appliance that allows the gas appliance to continue to be used when the pressure of the gas source is low.

In order to achieve the above object, the present invention provides a combustion control method for a gas appliance, wherein the gas appliance includes a burner for burning gas, and a gas valve is controlled to change its opening to adjust the amount of gas supplied to the burner. And a blower is controlled to change its rotational speed to adjust the amount of air supplied to the burner; the combustion control method comprises the following steps: A. calculating a total heating value required for the gas appliance; B, according to the first a heating total value controls the opening degree of the gas valve and the rotation speed of the blower; C, detecting the flame generated by the burner, and if no flame is detected, controlling the opening degree of the gas valve according to a second heating total value And the rotational speed of the blower, wherein the second heating total value is small The total value of the first heating.

The effect of the invention is that when the gas source pressure is low, the gas appliance can be continuously used, and the gas source is not misjudged when the gas source pressure is low, and the gas appliance can no longer be used.

[Use]

1‧‧ ‧ gas appliances

10‧‧‧ burner

12‧‧‧ gas valve

14‧‧‧Blowers

16‧‧‧Flame induction needle

18‧‧‧ Controller

20‧‧‧ gas pipeline

〔this invention〕

2‧‧ ‧ gas water heater

22‧‧‧heating unit

24‧‧‧ heat exchanger

242‧‧‧heat absorbing film

244‧‧‧Water pipes

26‧‧‧ Burner

28‧‧‧ gas pipeline

30‧‧‧ gas valve

32‧‧‧Blowers

34‧‧‧Ignition induction needle

36‧‧‧Water inlet

38‧‧‧Outlet

40‧‧‧Water tap

42‧‧‧Detection module

422‧‧‧Inlet water temperature detector

424‧‧‧Water temperature detector

426‧‧‧Water Flow Detector

44‧‧‧ Controller

442‧‧‧ memory

46‧‧‧Warning unit

G‧‧‧ Gas source

Figure 1 is a schematic view of a conventional gas appliance.

Fig. 2 is a schematic diagram showing the phenomenon of flying fire in a conventional gas appliance.

3 is a schematic diagram of a gas water heater to which a preferred embodiment of the present invention is applied.

4 is a flow chart of a combustion control method for a gas appliance according to a preferred embodiment of the present invention.

In order to explain the present invention more clearly, the preferred embodiment will be described in detail with reference to the accompanying drawings. Referring to FIG. 3, a gas water heater 2 for use in a preferred embodiment of the present invention includes a heating unit. 22. An inlet pipe 36, an outlet pipe 38, a detection module 42, a controller 44 and a warning unit 46.

The heating unit 22 includes a heat exchanger 24, a burner 26, a gas line 28, a gas valve 30, a blower 32 and an ignition sensor needle 34. The heat exchanger has a plurality of heat absorbing sheets 242 and a water conduit 244 extending through the heat absorbing sheets 242. The burner 26 is located below the heat exchanger 24 for combustion of the gas to heat the heat exchanger 24, the burner 26 being in communication with the gas line 28, the gas line 28 being connected to a gas source G. The gas valve 30 is disposed on the gas line 28, and the gas valve 30 is controllable Turn on or block the passing gas, and change the opening of its valve to adjust the amount of gas passing through. The blower 32 is in communication with the combustor 26, which is controlled to vary the rotational speed of its operating motor to regulate the amount of air supplied to the combustor 26. The ignition induction pin 34 is disposed adjacent to the burner 26 for igniting the gas output from the burner 26 and detecting the flame generated by the burner 26.

The water inlet pipe 36 and the water outlet pipe 38 respectively communicate with the water pipe 244 of the heat exchanger 24, and the water inlet pipe 36 is supplied with water, and the injected water flows out from the water outlet pipe 38 through the water pipe 244, and the water outlet pipe 38 is connected to One tap 40.

The detection module 42 includes a water inlet temperature detector 422, a water temperature detector 424, and a water flow detector 426. The detectors 422, 424, and 426 are respectively used to detect the water inlet temperature of the water inlet pipe 36. The outlet water of the outlet pipe 38 and the water flow rate of the inlet pipe 36.

The controller 44 is electrically connected to the ignition sensor pin 34, the gas valve 30, the air blower 32 and the detection module 42. The controller 44 controls the ignition sensor pin 34 to ignite, and detects whether the ignition sensor pin 34 senses a flame, and controls the gas valve 30 and the blower 32.

The controller 44 has a memory 442 having a plurality of heating total values and corresponding gas amount control parameters and rotational speed control parameters. Each heating total corresponds to a gas quantity control parameter and a speed control parameter. The controller 44 controls the opening degree of the gas valve 30 and the rotation speed of the blower 32 according to the gas amount control parameter and the rotation speed control parameter to achieve a certain air-fuel ratio. The controller 44 calculates the total heating value required by the burner 26 according to the inlet water temperature, the outlet water temperature and the water flow rate measured by the detection module 42, and the corresponding total heating value is retrieved from the memory 442. The gas quantity control parameter and the rotation speed control parameter control the gas valve 30 to adjust the gas volume and control the rotation speed of the air blower 32 so that the outlet water temperature reaches the outlet water temperature set by the user.

In this embodiment, the warning unit 46 is a display electrically connected to the controller 44 for displaying the message output by the controller 44. Of course, the warning unit 46 can also be a buzzer or a display and a buzzer. coexist.

The gas control method of the gas appliance shown in FIG. 4 can be executed by the gas water heater 2 described above, and the method comprises the following steps: the controller 44 controls the gas valve 30 to open the gas, and controls the ignition induction needle 34 to ignite. To ignite the gas output from the burner 26.

Calculating a required total heating value according to the water temperature set by the user, and extracting corresponding control parameters from the memory 442 according to the first heating total value to control the opening degree of the gas valve 30. And the rotational speed of the blower 32.

The ignition sensor 34 is used to detect whether the burner 26 generates a flame. If so, the pressure representing the current gas source G is normal, and the gas valve 30 and the blower 32 are normally operated; if not, the pressure deviation of the current gas source G is represented. Low or insufficient, a situation may occur in which the flying fire or the flame is extinguished. At this time, the controller 44 first controls the gas valve 30 to block the gas, and controls the blower 32 to maintain the operation and then controls the gas after a first predetermined time. Valve 30 opens and ignites the gas output from the combustor 26. The purpose of maintaining the blower 32 for operation is to evacuate residual gas and carbon monoxide in the gas water heater 2 to prevent residual gas and carbon monoxide from leaking to cause physical discomfort.

After the gas is ignited, the corresponding control parameter is extracted from the memory 442 according to a second heating total value to control the opening degree of the gas valve 30 and the rotation speed of the blower 32, wherein the second heating total value is In this embodiment, it is 70% of the total value of the first heating. In other words, the gas valve 30 is controlled to reduce the opening degree and reduce the rotation speed of the blower 32 to obtain a lower gas amount and air amount. In practice, you can also block the gas when no flame is detected. The opening degree of the gas valve 30 and the rotation speed of the blower 32 are controlled according to the second heating total value to obtain a lower gas amount and an air amount.

Then, the ignition sensor 34 detects whether the burner 26 generates a flame. If there is a flame, the pressure of the current gas source G is low but still unused. At this time, the controller 44 sends a first warning message to The warning unit 46 is to remind the user that the pressure of the gas source G has been low. If there is no flame, the gas representing the gas source G has been used or approached, and the gas cannot be used by the burner 26 or the fly fire is generated again. At this time, the controller 44 controls the gas valve 30 to block the gas and control it. The blower 32 is maintained in operation and stops the operation of the blower 32 after a second predetermined time to evacuate residual gas and carbon monoxide in the gas water heater 2. At the same time, the controller 44 sends a second warning message to the warning unit 46 to remind the user that the gas of the gas source G has not been used for gas or gas pressure for the burner 26 to reuse.

In the above description, the combustion control method of the present invention is described by taking the gas water heater 2 as an example. In addition to the gas water heater 2, the combustion control method of the present invention is more applicable to any gas supply type of the forced air supply type.

Through the combustion control method of the present invention, the pressure of the gas source in the user is low, but when the burner is still used, the flame is continuously ignited for the user to continue to use the gas appliance, thereby effectively improving the gas appliance used in the gas source. When the pressure is low, the user cannot use the gas appliance again. It is worth mentioning that the first warning message and the second warning message can effectively distinguish the state in which the pressure of the gas source is low or used.

The above is only a preferred embodiment of the present invention, and equivalent changes to the scope of the present invention and the scope of the patent application are intended to be included in the scope of the present invention.

Claims (8)

A combustion control method for a gas appliance, wherein the gas appliance comprises a burner for burning gas, a gas valve is controlled to change its opening to adjust the amount of gas supplied to the burner, and a blower is controlled to change its The rotation speed is used to adjust the amount of air supplied to the burner; the combustion control method comprises the following steps: A. calculating a total heating value required for the gas appliance; B, controlling the gas valve according to the first heating total value The opening degree and the rotation speed of the blower; and C, detecting the flame generated by the burner, if the flame is detected to be converted to the undetected flame, controlling the opening of the gas valve according to a second heating total value And the rotational speed of the blower, wherein the second heating total value is less than the first heating total value. The method of controlling a gas appliance according to claim 1, wherein the step C controls the gas valve to block the gas when the flame is not detected, and then controls the gas valve to open the gas and ignite the output from the burner. Gas, and then controlling the opening degree of the gas valve and the rotation speed of the blower according to the second heating total value. The method of controlling a gas appliance according to claim 2, wherein the step C is to control the blower to maintain operation after the gas barrier is blocked, and to control the gas after evacuating the residual gas after a first predetermined time. The gas valve opens and ignites the gas output from the burner. The method of controlling a gas appliance according to claim 1, wherein the step C comprises detecting the flame generated by the burner again, and issuing a first warning message when the flame is detected. The method of controlling a gas appliance according to claim 1, wherein the step C comprises a step D of detecting a flame generated by the burner and controlling the gas valve to block gas when no flame is detected. The method of controlling a gas appliance according to claim 5, wherein the step D further comprises controlling the blower to maintain operation and stopping after a second predetermined time elapses to evacuate the remaining gas. The method of controlling a gas appliance according to claim 5, wherein the step D comprises issuing a second warning message when the flame is not detected. The method of controlling a gas appliance according to claim 1, wherein the gas appliance is a gas heater.