Patent Application
20160238257
1. Field of the Invention
This invention relates to residential or commercial gas appliances. In particular, the invention relates to the smart gas range appliance that shall be equipped with electronic sensing element and can be remotely controlled by a mobile device. This invention is specifically for residential or commercial kitchen range that is operated with gas fuel. This invention is further related to micromachined silicon sensors or Micro Electro Mechanical Systems (MEMS) mass flow and gas sensing technology that measures the quality and quantity of gases. The present invention additionally relates to internet of things and the relay to the data clouding and analysis for which the smart range can transmit the data to the cloud via the mobile devices.
2. Description of the Related Art
It is always desirable to have a controllable device for residential or commercial appliances for safety, efficiency and intelligence purpose. While for an electrical heating apparatus or magnetic induction heating appliance that can provide direct electronic signals it is relatively easier to implement a control mechanism such as adding RFID sensing or temperature sensing elements, for example, U.S. Pat. No. 6,953,919 to Clothier, U.S. Pat. No. 7,255,100 to Pepper et al, and U.S. Pat. No. 5,951,500 to Smrke. Controlling the residential gas heating apparatus such as gas ranges with intelligent devices or modules is difficult, and relatively less disclosures could be found in literature. Akamatsu et al (U.S. Pat. No. 6,619,613) had proposed an apparatus that incorporated plurality of gas flow adjusting holes and step motors to adjust the openings of these holes such that different amount of gas can be delivered to the heating appliance. However, such an adjustment schedule shall only add the automation features in comparison to the existing vastly used adjustment mechanism with mechanical manual valves. Rothenberger and Weiss (U.S. Pat. No. 6,287,108) utilized a volumetric gas meter to provide the control of the gas opening valve such that the gas supply can be adjusted according to the desired gas volume. This approach is similar to the disclosure by Welz et al (U.S. Pat. No 6,247,919) where flow meter is used to provide the control baseline for a constant gas supply to an industrial burner. These disclosures therefore provide only the control capability according to the gas flow volume but they failed to response when the gas thermal value associated to the gas supply sources or gas compositions is varied. A constant volume supply at such a circumstance shall hence not be desired. Barritt and Pickering (U.S. Pat. No. 8,475,162) have further disclosed a cooking gas burner system in which a pressure sensor was used to gauge the gas supply and provide data to control a valve that adjust the heat by the gas to the cooking gas burner system. Similar invention to Schultz and Bergum (U.S. Pat. No. 8,635,997) also adapted a pressure regulator to modulate a gas valve or valves together with an inducer air flow fan that shall be also modulated by a pressure regulator such that the gas or gas fired appliance could be operated at its maximum efficiency. Both the above inventions however also would not be capable to measure the gas thermal mass value and the regulated gas volume via the pressure information could be fault to the desired operating efficiency. As the gas supplied usually shall not be identical in its physical and chemical properties from place to place which means that a constant volume control approach would not be able to used when the gas supply changes, which is likely one of the reasons that such appliances are not available at present since in particular the residential gas metrology is realized by volumetric technology only as of today.
Therefore it is desired to have a completed new approach or disclosure of a control device for the gas appliances that shall perform the mass flow sensing with thermal value metrology capability for the desired control features, which adds values of intelligence to the residential or commercial gas appliances such as gas ranges. This device shall be able to work for most of the gas supplies regardless of the gas properties and maintain good accuracy and reliability. The desired device with control features by integrated with both a sensor having the mass flow sensing and gas thermal value metering and an electrically controllable on/off valve. The sensing element of the device shall also be capable of metering or monitoring the gas leakage or a constant flow at a preset level while the device interfaces via the networking with a mobile device that provides the remote control to the device. Further there should not be any safety limitations for the desired device that shall be able to readily applicable for most of the gas pipelines for either residential or commercial gas appliances.
It is the objective of this invention to provide the design and structure of a device for residential or commercial appliances using gas fuel such as gas ranges. The device is incorporated with a sensor having both gas mass flow sensing and gas thermal value metering, and a control valve. The device shall have the capability of interfacing with a mobile device for providing remote management including shut-off of the gas supply via the network. The said device is a safety device for the appliances using gaseous fuel but not a replacement for the appliance operation switches. Further this invention disclosed the detailed assembly of the said device.
In one preferred embodiment, the invented device is in particular designed for residential or commercial gas appliances using natural gas or equivalent gas fuel as the primary heating source, such as gas ranges. The said device shall have the capability of metering the gas mass flow and the corresponding thermal values as well as the capability of shut-off the gas supply by an integrated valve at a certain programmable control value through interfacing remotely with a mobile device via the network. The said device shall be installed in serial on the gas supply pipeline that connected to the appliances operating by the gaseous fuel. The metered gas flow rate shall be as low as that of a value equivalent to the manufacture set leakage alarm, for the enhancement of the appliance safety.
In another preferred embodiment, the invented device shall be an executable device having the gaseous fuel flow rate sensing elements integrated with an executable on/off valve. The flow rate sensing elements are preferred to be an integrated silicon mass flow sensor with gaseous fuel thermal value measurement capability that shall provide an instant data rate to the control electronics on the device. The said on/off valve is preferred to be a fuel gas safety proof plastic rubber electrical-mechanical valve operating at a low voltage of 5Vdc and below. The said valve could also be a pulse self-priming valve that again shall be gas fuel safety proof operating at a low voltage with a reliable lifetime guaranteed. The said valve shall be controlled by the same electronics that reading the operating the said silicon mass flow rate sensing and gaseous fuel thermal valve sensing elements. The said sensing elements shall provide the instant gaseous fuel flow rate and thermal value to the electronics for further processing or executing the said valve operations.
In another preferred embodiment, the invented device with the capability of metering the gaseous fuel is accomplished by a silicon mass flow sensor made via the micro electro mechanical system fabrication process having a fast response time and wide dynamic range. The said mass flow sensor shall utilize the thermal calorimetric sensing principle that shall be independent of the variations of the environmental parameters such as pressure and temperature. The said mass flow sensor can be the one disclosed by the same inventor (U.S. Pat. Nos. 7,752,910; 7,765,679), but the said mass flow sensor can be further integrated with a thermal conductivity sensing element and a thermal capacity sensing element for additional compensation of the metering accuracy when the gaseous fuel composition has variations. The said mass flow sensor shall be package inside the device flow channel and pre-calibrated for the desired accuracy.
In another preferred embodiment, the invented device shall be able to detect the potential leakage flow rate of the said appliances set by the manufacturer. Otherwise it shall be capable of measurement for any constant flow rate pre-determined or pre-set at a desired time period by the users. The device shall evoke the remote mobile device via the network that such said leakage rate is presenting or the pre-set constant flow rate is overdue for the desired time period by the users. When the leakage state is detected or the desired time period for a constant flow rate is overdue, the said device shall signal to the remote mobile device via the network and the user can execute the gas supply shut-off procedure by remotely closing the constant open gaseous fuel valve integrated in the said device that is connected in serial with the appliance gas pipeline. In the preferred embodiment, the said device shall execute automatically the gas supply shut-off procedure for the ultimate safety and protections at a desired period of time when the signal to the remote mobile device returns no actions.
In another preferred embodiment, the said invented device shall have the capability of gaseous fuel flow rate metering that shall further have gaseous fuel thermal value measurement capability. While the flow rate metering can provide the leakage as well as gas appliance operation status, the thermal value measurement capability can be utilized to gauge the timing for the gas appliances in operation. In the preferred embodiment for gas ranges, the measurement of the timing for a desired substance cooked or heated to a desired condition shall be determined via the thermal value measurement by the said sensing elements for the specific gaseous fuel that provides the heating value for the said substance. Thereafter, the said device shall signal the status quo or condition in either percentage or remaining timing via the network to the desired remote mobile device further for a warning of possible performance overdue of the appliance. The said device shall also be capable to execute automatically the safety precautions when the overdue signals return no actions. The execution shall include but not limit to the execution of the gas supply shut-off by closing the integrated valve, and the addition route warning signals to the pre-set remote stations.
In yet at preferred embodiment, the invented device shall only be able to be reset on site to its constant open status at operation by the mobile device via the network when the gas supply to the appliance is terminated after valve close command is executed at the said conditions disclosed in the above. Further, the reset operation shall however be performed only after all the gas operation switches on the appliances by the original manufacturer are close tight. The remote reset capability of the device shall not be permitted for safety purpose.
For the current residential or commercial appliances operated with gaseous fuels, the present invention provides a solution for ultimate safety for overheating, unattended operation as well as gas leakage induced safety incidents. This invention further could provide the guidance for programmable appliances with use of a controllable proportional valve instead to those skilled in the art. This invention will no doubt become apparent to those skilled in the art after reading the following detailed description of the preferred embodiments that are illustrated in the accompanying drawings.
The preferred assembly of the said smart device of the said invention is shown in
The electrically controllable on/off valve 524 was sealed for preventing gas leakage with the gasket 523, and fixed to the metrology and control electronics unit by the two screws 527. The electrically controllable valve is then sealed and covered by the electrically controllable valve cover 525 and further fastened by the screws 526. The flow channel inside the electrically controllable valve is also aligned to the flow channels on the metrology and electronic control unit in one end and another end of the flow channel inside the electrically controllable valve shall be used to connect to the gas range gas supply pipelines. After the assembly, the complete device shall be ready to install onto the gas supply pipelines and connect to network via the wired interface connector 514 or the embedded wireless module.
After installation of the said smart device in serial to the gas supply pipeline of the gas range, the said smart device shall either be powered by explosive proof battery or an external power should the wired network interface is connected to the external network. While the metrology and control electronics of the said smart device is designed and manufactured to be intrinsic safe, the battery power shall provide a standalone device while the wired interface connection to the external network can be isolated with a standard safety barrier such that the gas safety can be ensured at the operation.
For the preferred embodiments, the actual sensing and control scheme of the said smart device attached in serial to the gas supply pipeline of the gas range is shown in
For the preferred embodiment, during normal operation of the said smart device, if the said smart device detects a constant flow rate that shall be above the minimal flow rate of the gas range operation at the end of a pre-set or pre-programmed time period, the said smart device shall send the current measured flow rate together with a warning message to the destined mobile device that is pre-paired to the said smart device via the wired or wireless network. The user of the destined mobile device can then be alerted and read the current flow rate of the connected gas range from the mobile terminal and make decision of action to either remotely close the electrically controllable valve or call relevant party to have the immediate attention. At the end of pre-set or pre-programmed time period for signal feedback, if the said smart device would not receive any feedback signal from the destined mobile device, the said smart device shall automatically execute the close valve procedure to close the electrically controllable valve to the gas supply pipeline. In the above preferred embodiment, the said smart device shall be able to intelligently complete the gas range operation at the desired status of the cooking substance and enhance the safety of the gas range operation.
For the preferred embodiment, during normal operation of the said smart device, the user can determine the required time period for preferred cooking substance by the metered thermal value of the supplied gas. In this preferred embodiment, the user shall be able to pre-set the time period at the time of starting the gas range. The said smart device shall then be operated at the gas thermal value detection mode. If the said smart device detects a constant flow rate that shall be above the minimal flow rate of the gas range operation at the end of a pre-set or pre-programmed time period, the said smart device shall send the current measured flow rate together with a warning message to the destined mobile device that is pre-paired to the said smart device via the wired or wireless network. The user of the destined mobile device can then be alerted and read the current flow rate of the connected gas range from the mobile terminal and make decision of action to either remotely close the electrically controllable valve or call relevant party to have the immediate attention. At the end of pre-set or pre-programmed time period for signal feedback, if the said smart device would not receive any feedback signal from the destined mobile device, the said smart device shall automatically execute the close valve procedure to close the electrically controllable valve to the gas supply pipeline. In the above preferred embodiment, the said smart device shall be able to prevent gas range from overheating or overcooking for whatsoever reasons and enhance the safety of the gas range operation.
