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:
Jan. 22, 2013
Filed:
Jan. 05, 2010
Kia Silverbrook, Balmain, AU;
Gregory John Mcavoy, Balmain, AU;
Angus John North, Balmain, AU;
Samuel George Mallinson, Balmain, AU;
Mehdi Azimi, Balmain, AU;
Kia Silverbrook, Balmain, AU;
Gregory John McAvoy, Balmain, AU;
Angus John North, Balmain, AU;
Samuel George Mallinson, Balmain, AU;
Mehdi Azimi, Balmain, AU;
Zamtec Ltd, Dublin, IE;
Abstract
A fluid sensor for detecting fluid in a chamber, has a MEMS sensing element of conductive material with a resistance that is a function of temperature, and electrical contacts for connection to an electrical power source for heating the sensing element with an electrical signal, so that control circuitry can measure the current passing through the sensing element during heating of the sensing element; and determine the temperature of the sensing element from the known applied voltage, the measured current and the known relationship between the current, resistance and temperature. As the temperature of the element will be greater if it is in the presence of gas rather than liquid, the sensor determines if there is liquid or gas in the chamber. This is particularly useful to detect if the chambers of an inkjet printhead are primed with ink.