Back to results
US 8,555,701 B1Granted
Enhanced metal oxide gas sensor
AssigneeCPS Products, Inc.
InventorJose L. Sacerio
Life of this patent
Estimating the term…
Abstract
A metal oxide sensor employing a method of heating that reduces the power required to heat the sensor to an optimal operating temperature and a method to automatically regulate and maintain the temperature of the sensors in the presence of air currents and other ambient conditions. The ultra miniature metal oxide sensors used have a thermal time constant short enough to allow for heating of the ultra miniature metal oxide sensors to occur with very narrow pulses of electricity. Such narrow pulses used to heat the sensor and to maintain the temperature such that the methods for reducing the power requirement apply throughout sensor's operation.
Claims19
A method of operating a semiconductor gas sensor comprising the steps of:
- providing a controller connected to a power supply, said controller being capable of applying electricity, ceasing the application of electricity, and receiving electrical signals through electrical connections;
- providing a sensing apparatus having a heating element and a sensing element, where the sensing apparatus is electrically connected to said controller through a first electrical pathway, the heating element increases in temperature when electricity is applied, the resistance of said heating element increases when the temperature of said heating element increases, the temperature of said sensing element increases when the temperature of said heating element increases, and the sensing element is a semi conductive material with a conductivity that changes in response to changes in its temperature;
- providing an operating temperature system comprising an operating comparator and an operating resistor of fixed resistance, said operating comparator having distinct electrical connections to said controller and said sensing apparatus and being able to compare the resistance of the operating resistor and the heating element, said operating comparator being able to provide an operating temperature signal electronically to the controller when the resistance of the heating element is not less than the resistance of the operating resistor;
- and
- where the controller applies electricity through the heating element in a series of narrow pulses.
2 more elements
A semiconductor gas sensor comprising:
- a controller connected to a power supply, said controller being capable of applying electricity, ceasing the application of electricity, and receiving electrical signals through electrical connections;
- a sensing apparatus having a heating element and a sensing element, where the sensing apparatus is electrically connected to said controller through a first electrical pathway, the heating element increases in temperature when electricity is applied, the resistance of said heating element increases when the temperature of said heating element increases, the temperature of said sensing element increases when the temperature of said heating element increases, and the sensing element is a semi conductive material with a conductivity that changes in response to changes in its temperature;
- an operating temperature system comprising an operating comparator and an operating resistor of fixed resistance, said operating comparator having distinct electrical connections to said controller and said sensing apparatus and being able to compare the resistance of the operating resistor and the heating element, said operating comparator providing an operating temperature signal electronically to the controller when the resistance of the heating element is not less than the resistance of the operating resistor;
- and
- where when electricity has been applied through the heating element until the said controller receives said operating temperature signal, the controller applies electricity through the sensing element.
2 more elements
A method of operating a semiconductor gas sensor comprising the steps of:
- providing a controller means for applying electricity, ceasing the application of electricity, and receiving electrical signals through electrical connections;
- providing a sensing means providing first variable resistance in a circuit the presence of gas or vapor;
- providing a heating means for heating said sensing means and providing a second variable resistance in a circuit due to changing temperature;
- providing an operating temperature system means for comparing the second variable resistance to a operating fixed resistance and for providing an operating signal to the controller when the second variable resistance is not less than the operating fixed resistance;
- and
- where the controller means applies electricity through the heating means in a series of narrow pulses.
3 more elements
Dependencies are inferred from the claim text.