Patents by Inventor Lihui Tu
Lihui Tu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 10536017Abstract: Disclosed are exemplary embodiments of controllers and methods for use in climate control systems. In an exemplary embodiment, a controller for use in a climate control system includes a charger for providing a charge current to a battery of the controller. The controller also includes a variable resistance for selectively limiting the charge current. A control is configured to monitor the charge current and a voltage of the battery. Based on the monitoring, the control varies the resistance to keep the monitored voltage in a range defined by (a) a top charge voltage less than full capacity of the battery and (b) a discharge end voltage greater than a cut-off voltage of the battery. The monitored voltage has a substantially minimized rate of change within the range.Type: GrantFiled: January 12, 2015Date of Patent: January 14, 2020Assignee: Emerson Electric Co.Inventors: Lihui Tu, Edward B. Evans
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Patent number: 9870008Abstract: Disclosed are exemplary embodiments of systems and methods for limiting DC voltage. In an exemplary embodiment, a DC voltage limiting circuit generally includes a current supply portion configured to receive a voltage input signal and provide a voltage output signal. A protective portion of the circuit is configured to limit or halt, at least temporarily, operation of the current supply portion based on a magnitude of the voltage input signal. A voltage level control portion is configured to limit the voltage output signal to a predetermined voltage level. In some embodiments, the DC voltage limiting circuit is provided in a climate control system controller.Type: GrantFiled: March 18, 2015Date of Patent: January 16, 2018Assignee: Emerson Electric Co.Inventors: Li Han, Liang Cao, Lihui Tu, Bradley C. Zikes
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Patent number: 9739499Abstract: A controller for use in a climate control system. The controller, which may be a wireless-enabled thermostat, includes a power stealing circuit configured to steal power from a first load that is in an “on” mode and from a second load that is in an “off” mode. The stealing is performed from the first and second loads at the same time. Sufficient power can be stolen to support substantially constant operation of a transceiver of the controller.Type: GrantFiled: March 24, 2014Date of Patent: August 22, 2017Assignee: Emerson Electric Co.Inventors: Lihui Tu, Cuikun Chu, Zhongliang Xu, Long Huang
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Publication number: 20160259350Abstract: Disclosed are exemplary embodiments of systems and methods for limiting DC voltage. In an exemplary embodiment, a DC voltage limiting circuit generally includes a current supply portion configured to receive a voltage input signal and provide a voltage output signal. A protective portion of the circuit is configured to limit or halt, at least temporarily, operation of the current supply portion based on a magnitude of the voltage input signal. A voltage level control portion is configured to limit the voltage output signal to a predetermined voltage level. In some embodiments, the DC voltage limiting circuit is provided in a climate control system controller.Type: ApplicationFiled: March 18, 2015Publication date: September 8, 2016Inventors: Li Han, Liang Cao, Lihui Tu, Bradley C. Zikes
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Patent number: 9404667Abstract: Disclosed are exemplary embodiments of systems and methods for determining a power stealing capability of a climate control system controller. In an exemplary embodiment, a controller for use in a climate control system generally includes a capacitor chargeable by current flowing through an off-mode load of the climate control system. A voltage detect circuit detects a voltage across the capacitor. The controller includes a timer for determining a charge time of the capacitor from a first specific voltage to a second specific voltage based on input from the voltage detect circuit. The controller determines a resistance of the off-mode load based on the charge time and, based on the determined resistance, determines a level of current for power stealing through the off-mode load.Type: GrantFiled: October 30, 2013Date of Patent: August 2, 2016Assignee: Emerson Electric Co.Inventors: Lihui Tu, Cuikun Chu
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Publication number: 20160161563Abstract: Disclosed are exemplary embodiments of devices for measuring voltage of a power supply. Also disclosed are exemplary embodiments of detection devices and temperature controllers comprising such devices for measuring voltage of a power supply. In exemplary embodiments, a device for measuring the voltage of a power supply generally includes a resistor, a capacitor, and a control unit. One end of the capacitor is connected with the resistor, while the other end of the capacitor is connected to ground. The control unit is connected with the power supply. The control unit includes a comparator connected with the capacitor, a reference power supply connected with the comparator, a timer, and a computing unit.Type: ApplicationFiled: February 15, 2016Publication date: June 9, 2016Inventors: Lihui Tu, Liang Cao, Cuikun Chu
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Patent number: 9261540Abstract: Disclosed are exemplary embodiments of devices for measuring voltage of a power supply. Also disclosed are exemplary embodiments of detection devices and temperature controllers comprising such devices for measuring voltage of a power supply. In exemplary embodiments, a device for measuring the voltage of a power supply generally includes a resistor, a capacitor, and a control unit. One end of the capacitor is connected with the resistor, while the other end of the capacitor is connected to ground. The control unit is connected with the power supply. The control unit includes a comparator connected with the capacitor, a reference power supply connected with the comparator, a timer, and a computing unit.Type: GrantFiled: January 13, 2014Date of Patent: February 16, 2016Assignee: Emerson Electric Co.Inventors: Lihui Tu, Liang Cao, Cuikun Chu
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Publication number: 20160006274Abstract: Disclosed are exemplary embodiments of controllers and methods for use in climate control systems. In an exemplary embodiment, a controller for use in a climate control system includes a charger for providing a charge current to a battery of the controller. The controller also includes a variable resistance for selectively limiting the charge current. A control is configured to monitor the charge current and a voltage of the battery. Based on the monitoring, the control varies the resistance to keep the monitored voltage in a range defined by (a) a top charge voltage less than full capacity of the battery and (b) a discharge end voltage greater than a cut-off voltage of the battery. The monitored voltage has a substantially minimized rate of change within the range.Type: ApplicationFiled: January 12, 2015Publication date: January 7, 2016Inventors: Lihui Tu, Edward B. Evans
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Patent number: 9207817Abstract: Exemplary embodiments are disclosed of touchscreen devices for thermostats and other electronic devices. In an exemplary embodiment, a capacitive touchscreen device includes a touchscreen having touch regions. Each touch region is coupled with at least one first capacitor and at least one second capacitor. The second capacitors are connected in parallel and have smaller capacitance than the first capacitors. The capacitive touchscreen device may be configured to be operable in a standby mode in which the second capacitors are charged and an active mode in which the first capacitors are charged.Type: GrantFiled: November 7, 2012Date of Patent: December 8, 2015Assignee: Emerson Electric Co.Inventor: Lihui Tu
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Publication number: 20150115045Abstract: Disclosed are exemplary embodiments of systems and methods for determining a power stealing capability of a climate control system controller. In an exemplary embodiment, a controller for use in a climate control system generally includes a capacitor chargeable by current flowing through an off-mode load of the climate control system. A voltage detect circuit detects a voltage across the capacitor. The controller includes a timer for determining a charge time of the capacitor from a first specific voltage to a second specific voltage based on input from the voltage detect circuit. The controller determines a resistance of the off-mode load based on the charge time and, based on the determined resistance, determines a level of current for power stealing through the off-mode load.Type: ApplicationFiled: October 30, 2013Publication date: April 30, 2015Applicant: Emerson Electric Co.Inventors: Lihui Tu, Cuikun Chu
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Publication number: 20140312694Abstract: A controller for use in a climate control system. The controller, which may be a wireless-enabled thermostat, includes a power stealing circuit configured to steal power from a first load that is in an “on” mode and from a second load that is in an “off” mode. The stealing is performed from the first and second loads at the same time. Sufficient power can be stolen to support substantially constant operation of a transceiver of the controller.Type: ApplicationFiled: March 24, 2014Publication date: October 23, 2014Inventors: Lihui Tu, Cuikun Chu, Zhongliang Xu, Long Huang
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Publication number: 20140285222Abstract: Disclosed are exemplary embodiments of devices for measuring voltage of a power supply. Also disclosed are exemplary embodiments of detection devices and temperature controllers comprising such devices for measuring voltage of a power supply. In exemplary embodiments, a device for measuring the voltage of a power supply generally includes a resistor, a capacitor, and a control unit. One end of the capacitor is connected with the resistor, while the other end of the capacitor is connected to ground. The control unit is connected with the power supply. The control unit includes a comparator connected with the capacitor, a reference power supply connected with the comparator, a timer, and a computing unit.Type: ApplicationFiled: January 13, 2014Publication date: September 25, 2014Applicant: Emerson Electric Co.Inventors: Lihui Tu, Liang Cao, Cuikun Chu
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Publication number: 20130310985Abstract: Exemplary embodiments are disclosed of touchscreen devices for thermostats and other electronic devices. In an exemplary embodiment, a capacitive touchscreen device includes a touchscreen having touch regions. Each touch region is coupled with at least one first capacitor and at least one second capacitor. The second capacitors are connected in parallel and have smaller capacitance than the first capacitors. The capacitive touchscreen device may be configured to be operable in a standby mode in which the second capacitors are charged and an active mode in which the first capacitors are charged.Type: ApplicationFiled: November 7, 2012Publication date: November 21, 2013Applicant: Emerson Electric Co.Inventor: Lihui Tu