The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 23, 2012
Filed:
Jul. 14, 2006
Mitsuharu Kira, Nishinomiya, JP;
Mitsuharu Kira, Nishinomiya, JP;
FIS Inc., Itama-shi, JP;
Abstract
A gas detection apparatus A comprises a signal processing circuita Wheatstone bridge circuitintegrating circuitsanda differential amplification circuita direct current power supply circuita heater voltage application circuitThe Wheatstone bridge circuitis configured of parallel combination of series circuits: one composed of a catalytic combustion type gas sensorand a load resistor R, and the other composed of a resistor Ra variable resistor VRand a resistor RThe heater voltage application circuitis configured to generate a pulsed heater voltage by switching a direct current voltage of the direct current power supply circuitthrough a transistor TRfor applying the pulsed heater voltage to the Wheatstone bridge circuitThe integrating circuitintegrates a voltage at a connection point between the gas sensorand the load resistor R. The integrating circuitintegrates a voltage at a connection point between the variable resistor VRand the resistor RThe differential amplification circuitis configured to amplify a differential voltage between the output voltages of the integrating circuitsandThe signal processing circuitis configured to determine a concentration of a flammable gas from an output voltage of the differential amplification circuit