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:
Aug. 28, 2001
Filed:
Apr. 27, 1999
Kurt Karlsson, Tyresö, SE;
Stig Lundin, Värmdö, SE;
ABB Air Preheater Inc., Wellsville, NY (US);
Abstract
A method and an arrangement for sensing the clearance between an object and an object-adjacent surface, which is particularly for use in difficult ambient conditions, such as in dirty, corrosive environments and under varying temperature and pressure conditions, e.g. to measure and hold constant the clearance between the sector plates (,) of a regenerative rotary air preheater and the end surfaces of the rotor (,). The sensing device (,) includes a compressed-air operated pipe (,) which is mounted on the object (,) and which includes a sound-emitting opening (,) located adjacent the surface (,), wherein changes in the distance (S) between the object (,) and the surface (,) are represented by changes that occur in the resonant frequency of the pipe (,).