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:
Dec. 27, 1988
Filed:
Oct. 08, 1986
Rodney L Derbyshire, Menlo Park, CA (US);
Metcal, Inc., Menlo Park, CA (US);
Abstract
A self-regulating porous heater device regulates the temperature of fluid passing through it. This device includes at least one layer of a porous material which has a magnetic permeability inversely related to temperature over a given range. Due to conductor skin effects, changes in permeability cause changes in the depth of penetration of a.c. current passing through the magnetic layer. Changes in the depth of penetration, in turn, result in changes in resistance--the less the depth the greater resistance--and in I.sup.2 R Joule heat. The combined result of these effects is to provide more heat where the temperature of the fluid and the layer through which the fluid flows is below a specified temperature which is related to the Curie temperature of the layer. The device can have a laminate structure including a porous magnetic layer and at least one other magnetic layer or at least one low resistance nonmagnetic layer or a combination thereof, which may or may not be porous. By properly defining pore dimensions, the heater device can filter contaminants from a fluid as it flows therethrough. Switching between a normal operating temperature and an elevated temperature for vaporizing or burning off contaminants at the pores is provided. In a preferred mode, a porous heater device is included in a chemical reaction chamber for exothermic reactions.