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. 14, 1993
Filed:
Jul. 21, 1992
Gerhard Schmid, Mittelberach, DE;
Abstract
A device for heating flowing media in a handpiece, particularly air or water for use in dentistry procedures, includes a structural unit for controllably heating a flowing medium disposed in a housing in a sealed manner such that an annular flow passage is formed between an interior wall of the housing and the structural unit. The structural unit includes a PTC resistor having end faces disposed between and in thermal and electrical contact with a pair of porous sintered metal heat exchanger elements at a non-zero angle to the direction of medium flow. Connectors on the opposing ends of the unit contact the sintered heat exchanger elements to flow connect the structural unit in a medium flow line and to electrically connect the PTC resistor to a heating control circuit. A flow passage extends from each connector into the respective sintered heat exchanger element so that the medium flows from one heat exchanger element to the other by flowing through the annular flow passage, thus providing a large heat exchange area in a small space.