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:
Sep. 10, 2002
Filed:
Mar. 30, 2000
Thomas O. Maginnis, Jr., Dracut, MA (US);
MKS Instruments, Inc., Andover, MA (US);
Abstract
A thermal mass flow sensor in which heat transfer to and from a fluid flowing through a sensor conduit is optimized by establishing a symmetrical triangular temperature distribution along a heated length of the sensor conduit. The sensor conduit is heated by a pair of distributed heat sources and a concentrated heat source located between the distributed heat sources. The heater density of the sensor conduit increases linearly from the outer ends of the distributed heat sources towards the center of the heated length of the sensor conduit, and spikes to a substantially greater value at a point corresponding to the centrally located concentrated heat source. The temperature distribution function along the flow sensor tube is a substantially symmetric triangular function.