Patent ID: 12188579

DETAILED DESCRIPTION OF THE INVENTION

The following illustrative embodiments and drawings are provided to illustrate the disclosure of the present invention, these and other advantages and effects can be clearly understood by persons skilled in the art after reading the disclosure of this specification.

As illustrated inFIG.1, a gas appliance1of a first embodiment according to the present invention is for connecting a gas supply pipe P. The gas supply pipe P is for injecting natural gas provided by gas suppliers. The natural gas is one of a first natural gas and a second natural gas, and a heating value of the first natural gas and that of the second natural gas are different. In the current embodiment, the heating value of the first natural gas is less than that of the second natural gas. The heating value of the first natural gas is 8900 Kcal/M3 as an example, and the heating value of the second natural gas is 9700 Kcal/M3 as an example, but it is not limited thereto. The gas appliance1comprises a combustion device10, an ignitor12, a gas valve14, a blower16, a detecting device18, and a control device20.

The combustion device10is for burning the natural gas to generate flames. The ignitor12is disposed beside the combustion device10to generate a spark to ignite the natural gas output by the combustion device10to form flames.

The gas valve14communicates with the gas supply pipe P and the combustion device10, and is controlled to change a gas flow supplied to the combustion device10. In the current embodiment, the gas valve14is provided with a gas regulating valve142to regulate the gas flow supplied to the combustion device10. The gas valve14is further provided with a passage solenoid144to open or block the gas flowing to the combustion device10.

The blower16provides combustible air to the combustion device10. The blower16can be controlled to change a rotation speed to change the air flow supplied to the combustion device10. In the current embodiment, an air outlet of the blower16is connected to a mixer22disposed between the gas valve14and the combustion device10. Gas output by the gas valve14is mixed with air through the mixer22and then is supplied to the combustion device10.

The detecting device18is for directly or indirectly detecting burning states of the flames of the combustion device10. To directly detect the burning states of the flames can be direct contact with the flames, or at a distance from the flames without contacting the flames. To indirectly detect the burning states of the flames can be by detecting the product of gas combustion, or by detecting the characteristics of the substance heated by the flames, to get the burning state of the flames accordingly. In the current embodiment, the detecting device18includes a thermocouple182for contacting the flames, detecting the flames generated by the combustion device10, and outputting a corresponding detection voltage which corresponds to the burning state of the flames of the combustion device10.

The control device20electrically connects the gas valve14, the blower16, and the detecting device18. The control device20is for controlling the operation of the gas valve14and the blower16to change the gas flow and the air flow supplied to the combustion device10, and to receive the burning states detected by the detecting device18. The control device20has a memory202storing a first control data and a second control data. The first control data corresponds to the first natural gas and controls the gas valve14and the rotation speed of the blower16to reach a preferred ratio of the air flow to the first natural gas flow, in which the first control data provides corresponding air flow at different gas flow rates. The second control data corresponds to the second natural and controls the gas valve14and the rotation speed of the blower16to reach a preferred ratio of the air flow to the second natural gas flow, in which the second control data provides corresponding air flow at different gas flow rates. The memory202further stores an initial control data which controls the gas valve14to supply a fixed gas flow and controls the blower16to run at a fixed speed and provide a fixed air flow. In the current embodiment, the initial control data corresponds to the first natural gas flow to provide a preferred ratio of the air flow to the first natural gas flow, but it is not limited thereto. Under the circumstances, if the gas supplied by the gas supply pipe P is the first natural gas, the combustion device10has better combustion efficiency and a burning state of the flames at this time can be predefined as a first state. If the gas supplied by the gas supply pipe P is the second natural gas, the combustion device10has poor combustion efficiency and a burning state of the flames at this time can be predefined as a second state. In the current embodiment, when the burning state of the flames is the first state, the combustion efficiency is better and the detection voltage output by the thermocouple182is greater than a predetermined voltage. On the contrary, when the detection voltage output by the thermocouple182is less than the predetermined voltage, the burning state of the flames is the second state.

In one embodiment, the initial control data corresponds to the ratio of the air flow to the second natural gas flow. If the gas supplied by the gas supply pipe P is the first natural gas, the combustion device10has poor combustion efficiency and a burning state of the flames at this time can be predefined as a first state. If the gas supplied by the gas supply pipe P is the second natural gas, the combustion device10has better combustion efficiency and a burning state of the flames at this time can be predefined as a second state.

The control device20can be operated in a detection mode, a first operation mode, or a second operation mode. Wherein, the detection mode is to determine whether the supplied gas is the first natural gas or the second natural gas. The first operation mode is for controlling the gas valve14and the blower16in correspondence to the first control data of the first natural gas. The second operation mode is for controlling the gas valve14and the blower16in correspondence to the second control data of the second natural gas.

In the current embodiment, the control device20is further connected to an operation interface24in a wired or wireless manner. The operation interface24is for a user to operate to output a detection signal or a start signal to the control device20, in which the detection signal commands the control device20to execute the detection mode while the start signal commands the control device20to be operated in the first operation mode or the second operation mode which are determined by the detection mode. The operation interface24includes at least one switch to output a detection signal and a start signal. For example, long press the switch for a few seconds to form the detection signal and short press the switch to form a start signal. In practice, there can be two switches including a detection switch and a start switch, in which the detection switch is for a user to operate to output the detection signal to the control device20while the start switch is for the user to operate to output the start signal to the control device20. In one embodiment, the source of the detection signal can be provided by an external electronic device via a communication network.

The control device20executes a control method illustrated inFIG.2, the control method comprising the following steps:

When the gas appliance1is on standby, the control device20is operated in the detection mode when receiving the detection signal. In the detection mode, the control device20controls the ignitor12to ignite and controls the gas valve14and the blower16to provide a fixed gas flow and a fixed air flow to the combustion device10. In the current embodiment, the operation interface24is operated by a user to output the detection signal to the control device20. In the detection mode, the control device20activates the ignitor12to ignite and controls the gas valve14and the blower16in correspondence to the initial control data to provide the fixed gas flow and the fixed air flow to the combustion device10. In this way, the gas can burn steadily and generate a stable burning state which will not change due to changes in the gas flow or the air flow.

After igniting the flames, the detecting device18detects the burning states of the flames of the combustion device10. The control device20determines the burning state detected by the detecting device matches the first state or the second state. In the current embodiment, the control device20determines whether the detection voltage output by the thermocouple182is greater than the predetermined voltage, and then determines whether the first state or the second state is matched.

If the detection voltage is greater than the predetermined voltage, it is determined that the burning state of the flames matches the first state, which represents that the gas supplied by the gas supply pipe P is the first natural gas. The control device20is then switched to be operated in the first operation mode, in which the control device20controls the gas valve14and the blower16according to the first control data in correspondence to the first natural gas so that the combustion device10is suitable for burning the first natural gas. In other words, the ratio of the air flow to the first natural gas flow is better in the first operation mode so that the combustion device10has better combustion efficiency. The first operation mode is configured by the control device20to be a preset operation mode, and subsequently the control device20runs in the first operation mode. After the control device20controls the gas valve14to block gas and controls the blower16to stop running, the gas appliance is on standby. When receiving the start signal, the control device20is operated in the preset operation mode (that is, the first operation mode), in which the control device20controls the ignitor12to ignite, and controls the gas valve14and the blower16in correspondence to the first control data.

If detection voltage is less than the predetermined voltage, it is determined that the burning state of the flames matches the second state, which represents that the gas supplied by the gas supply pipe P is the second natural gas. The control device20is then switched to be operated in the second operation mode, in which the control device20controls the gas valve14and the blower16according to the second control data in correspondence to the second natural gas so that the combustion device10is suitable for burning the second natural gas. In other words, the ratio of the air flow to the second natural gas flow is better in the second operation mode so that the combustion device10has better combustion efficiency. The second operation mode is configured by the control device20to be a preset operation mode, and subsequently the control device20runs in the second operation mode. After the control device20controls the gas valve14to block gas and controls the blower16to stop running, the gas appliance1is on standby. When receiving the start signal, the control device20is operated in the preset operation mode (that is, the second operation mode), in which the control device20controls the ignitor12to ignite, and controls the gas valve14and the blower16in correspondence to the second control data.

In one embodiment, when the control device20in the detection mode determines that the burning state detected by the detecting device18does not matches the first state and the second state, the control device20controls the gas valve14to block gas and controls the blower16to stop running. For example, if the detection voltage of the thermocouple182is greater than the predetermined voltage, it represents the first state; if the detection voltage is less than the predetermined voltage and greater than another one predetermined voltage, it represents the second state; if the detection voltage is less than the another one predetermined voltage, it represents a third state (does not match the first state and the second state.) The third state means poor combustion efficiency, in which the control device20controls the gas valve14to block gas and controls the blower16to stop running to avoid danger.

With the above-mentioned control method, the control device20can determine whether the gas supplied by the gas supply pipe P is the first natural gas or the second natural gas in correspondence to the burning state of the flames detected by the detection mode, and the preset operation mode can be configured to be the corresponding first operation mode or the second operation mode. Then, after the gas appliance1is on standby or turned off and on again, the control device20controls the gas valve14and the blower16in the preset operation mode to be suitable for burning the first natural gas or the second natural gas.

After that, the user operates the operation interface24to output the detection signal to the control device20, and the control device20can be operated in the detection mode again so that the preset operation mode is configured to be the suitable first operation mode or the second operation mode.

To prevent the natural gas supplied by the gas supply pipe P from being changed during the use of the gas appliance1, in the current embodiment, after the control device20is operated in the first operation mode or the second operation mode, it will be operated in the detection mode to determine whether the gas supplied by the gas supply pipe P is the first natural gas or the second natural gas.

After the control device20is operated in the first operation mode, the control device20will be operated in the detection mode at predetermined intervals, and the predetermined interval may be, for example, 20 to 30 minutes. In the detection mode, the control device20controls the gas valve14and the blower16to provide a fixed gas flow and a fixed air flow to the combustion device10. The control device20determines whether the burning state detected by the detection device18matches the first state or the second state. If matching the first state, it represents that the natural gas is still the first natural gas and the control device20is operated in the first operation mode. If matching the second state, it represents that the natural gas has turned to be the second natural gas. The control device20is then switched to be operated in the second operation mode which is then configured to be the preset operation mode.

After the control device20is operated in the second operation mode, the control device20will be operated in the detection mode at the predetermined intervals. The control device20controls the gas valve14and the blower16to provide a fixed gas flow and a fixed air flow to the combustion device10, and determines whether the burning state detected by the detection device18matches the first state or the second state. If matching the second state, it represents that the natural gas is still the second natural gas and the control device20is operated in the second operation mode. If matching the first state, it represents that the natural gas has turned to be the first natural gas. The control device20is switched to be operated in the first operation mode which is then configured to be the preset operation mode.

A gas appliance2of a second preferred embodiment according to the present invention is shown inFIG.3, wherein the gas appliance2includes a structure which is similar to the gas appliance1of the first embodiment, except that the combustion device26is disposed in a combustion chamber28and includes a pilot fire burner262and a main fire burner264.

The gas valve30communicating the pilot fire burner262and the main fire burner264has a pilot fire solenoid valve302, a main fire solenoid valve304, and a gas regulating valve306inside. The pilot fire solenoid valve302and the main fire solenoid valve304are respectively to open or block the gas flowing to the pilot fire burner262and the main fire burner264, and the gas regulating valve306is to regulate the gas flowing to the main fire burner264.

An air outlet of a blower32is communicated to the combustion chamber28to provide combustible air to the combustion chamber28.

A detecting device34includes a flame sensing electrode342for detecting an impedance of the flames which is generated by the combustion device26. In the current embodiment, the flame sensing electrode342is disposed at the combustion chamber28beside the pilot fire burner262. The flame sensing electrode342electrically connects a control device36. Since flames are conductive, the higher the combustion efficiency, the more contact area between flames and the flame sensing electrode342, and the lower impedance detected by the flame sensing electrode342. Therefore, the impedance of the flames detected by the flame sensing electrode342is in correspondence to the burning state of the flames of the combustion device26.

Accordingly, the control device36can be applied to the control method of the first embodiment. The difference is that when the ignitor12is controlled to ignite, the control device36controls the pilot fire solenoid valve302to open to ignite the pilot fire. After the flame sensing electrode342detects flames of the pilot fire, the control device36controls the main fire solenoid valve304to open and controls the gas regulating valve306to regulate the gas flowing to the main fire burner264. As long as the pilot fire solenoid valve302is controlled to keep open, the gas flow rate supplied to the pilot fire burner262can be fixed. Since the air flow supplied by the blower32is provided to the pilot fire burner262and the main fire burner264, the burning states of the flames of the combustion device26can be obtained by detecting the flames generated by the pilot fire burner262. In one embodiment, a flame sensing electrode can also be disposed beside the main fire burner264so to detect the burning states of the flames generated by the main fire burner264.

In the detection mode, the control device36determines whether the burning state is the first state or the second state in correspondence to the impedance of the flames detected by the flame sensing electrode342. When the detected impedance of the flames is less than a predetermined impedance, the control device36determines that the first state is matched, which represents that the natural gas is the first natural gas. When the detected impedance of the flames is greater than a predetermined impedance, the control device36determines that the second state is matched, which represents that the natural gas is the second natural gas.

In this way, the control device36can be switched to be operated in the first operation mode or the second operation mode in correspondence to the flames state detected by the detection mode.

A gas appliance3of a third preferred embodiment according to the present invention is shown inFIG.4, wherein the gas appliance3includes a structure which is similar to the gas appliance2of the second embodiment, except that the detection device34includes a flame height detection module38. The flame height detection module38is for detecting a height of the flames generated by the combustion device26, and the detected height of the flames corresponds to the burning state of the flames of the combustion device26. The flame sensing electrode342is for detecting whether the flames of the pilot fire is present or not.

In the current embodiment, the flame height detection module38includes two flame sensing electrodes382electrically connecting the control device36. The two flame sensing electrodes382are disposed above the main fire burner264at different heights respectively to detect the height of the flames generated by the main fire burner264.

The height of the flames when the flames is in contact with the flame sensing electrode382at a higher position is defined as a predetermined height.

In the detection mode, when the height of the flames detected by the flame height detection module38is greater than the predetermined height, the control device36determines that the first state is matched, which represents that the natural gas is the first natural gas. When the height of the flames detected by the flame height detection module38is less than the predetermined height, which means the flames is only in contact with the flame sensing electrode382at a lower position, the control device36determines that the second state is matched, which represents that the natural gas is the second natural gas.

In this way, the control device36can be switched to be operated in the first operation mode or the second operation mode in correspondence to the flames state detected by the detection mode.

The gas appliance4of a fourth preferred embodiment according to the present invention is shown inFIG.5, wherein the gas appliance4includes a structure which is similar to the gas appliance2of the second embodiment, except that the detection device34includes an infrared detector40for detecting intensity of infrared ray generated by the combustion device26, and the detected intensity of the infrared ray corresponds to the burning state of the flames of the combustion device26. The flame sensing electrode342is for detecting whether the flames of the pilot fire is present or not.

When the detected intensity of the infrared ray is greater than a predetermined intensity, the control device36determines that the first state is matched, which represents that the natural gas is the first natural gas. When the detected intensity of the infrared ray is less than the predetermined intensity, the control device36determines that the second state is matched, which represents that the natural gas is the second natural gas.

In this way, the control device36can be switched to be operated in the first operation mode or the second operation mode in correspondence to the flame state detected by the detection mode.

The gas appliance5of a fifth preferred embodiment according to the present invention is shown inFIG.6, which is an example of a water heater. The gas appliance5includes a structure which is similar to the gas appliance2of the second embodiment, except that the gas appliance5comprises a water pipe42including an inlet pipe section422, a heating pipe section424, and an outlet pipe section426connected in sequence. The heating pipe section424is disposed above the combustion device26. The flames generated by the combustion device26heats the heating pipe section424. The detection device34includes an inlet water temperature detector44, an outlet temperature detector46, and a water flow detector48electrically connecting to the control device36. The inlet water temperature detector44and the water flow detector48are disposed at the inlet pipe section422while the outlet temperature detector46is disposed at the outlet pipe section426. The inlet water temperature detector44, the outlet temperature detector46, and the water flow detector48respectively detect an inlet water temperature, an out water temperature, and a water flow.

An exhaust passage50disposed above the water pipe42communicates with the combustion device26. The gas generated by the combustion device26burning the natural gas exhausts through the exhaust passage50.

In the current embodiment, the control device36is operated in the detection mode when the operation interface24outputs the detection signal and the water flow detector48detects the water flowing. In the detection mode, the control device36determines whether the burning state is the first state or the second state in correspondence to the impedance of the flames detected by the flame sensing electrode342. When the detected impedance of the flames is less than a predetermined impedance, the control device36determines that the first state is matched, which represents that the natural gas is the first natural gas. When the detected impedance of the flames is greater than the predetermined impedance, the control device36determines that the second state is matched, which represents that the natural gas is the second natural gas.

In this way, the control device36can be switched to be operated in the first operation mode or the second operation mode in correspondence to the flame state detected by the detection mode.

When operated in the first operation mode or the second operation mode, the control device36controls the gas valve30and the blower32in correspondence to the inlet water temperature, the outlet water temperature, the water flow, and a set temperature.

The gas appliance6of a sixth preferred embodiment according to the present invention is shown inFIG.7, wherein the gas appliance6includes a structure which is similar to the gas appliance5of the fifth embodiment, except that the flame sensing electrode342is for detecting whether the flames of the pilot fire is present or not. The outlet water temperature detector46of the detecting device34detects an outlet water temperature of the outlet pipe section426, in which the outlet water temperature corresponds to the burning state of the flames of the combustion device26. In the detection mode, since there is a fixed gas flow and a fixed air flow, the combustion efficiency is good when the outlet water temperature is greater than a predetermined temperature, and the control device36determines that the first state is matched, which represents that the natural gas is the first natural gas. The combustion efficiency is poor when the outlet water temperature is less than the predetermined temperature, and the control device36determines that the second state is matched, which represents that the natural gas is the second natural gas.

Alternatively, rather than determining the burning states of the flames by the outlet water temperature, in a detection mode, the control device36calculates the combustion efficiency in correspondence to the inlet water temperature, the outlet water temperature, and the water flow. When the combustion efficiency is greater than a predetermined efficiency, it is determined that the first state is matched, and when the combustion efficiency is less than a predetermined efficiency, it is determined that the second state is matched.

The gas appliance7of a seventh preferred embodiment according to the present invention is shown inFIG.8, wherein the gas appliance7includes a structure which is similar to the gas appliance5of the fifth embodiment, except that the flame sensing electrode342is for detecting whether the flames of the pilot fire is present or not. The detecting device34includes a gas detector52, in which the gas detected by the gas detector52is carbon monoxide, but it is not limited thereto, it can detect carbon dioxide. The gas detector52is disposed in the exhaust passage50and detects a concentration of passing gas, in which the concentration of the detected passing gas corresponds to the burning state of the flames of the combustion device26.

In the detection mode, when the concentration of the detected passing gas is less than a predetermined concentration, the combustion efficiency is good and the control device36determines that the first state is matched, which represents that the natural gas is the first natural gas. When the concentration of the detected passing gas is less than the predetermined concentration, the combustion efficiency is poor and the control device36determines that the second state is matched, which represents that the natural gas is the second natural gas.

As mentioned above, the gas appliance of the present invention can determine that the natural gas supplied by the gas supply pipe P is the first natural gas or the second natural gas in correspondence to the flame states, and the gas appliance can be configured to the corresponding first operation mode or the second operation mode to be suitable for burning the first natural gas or second natural gas with various heating values.

It must be pointed out that the embodiments described above are only some embodiments of the present invention. All equivalent structures which employ the concepts disclosed in this specification and the appended claims should fall within the scope of the present invention.