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:
Jul. 12, 1988
Filed:
Apr. 18, 1987
Raimo Rajala, Kaarina, FI;
Raimo Virta, Turku, FI;
Valmet Oy, , FI;
Abstract
Method and Apparatus for Measuring Permeability to Air of a Wall-Like or Sheet-Like Element, comprising the use of a measurement head including a blower having an air-discharge nozzle, a blade wheel and a variable-speed motor for rotating the wheel to produce an air flow which discharges through the nozzle. Pressure in the blower and speed of blade wheel rotation are detected, with appropriate signals indicative thereof being input to a central unit which then appropriately adjusts speed of rotation of the blade wheel to correspond to a predetermined blower pressure value. Permeability value of the element is then determined at the central unit, based on relationship between the speed measurement signal values, and corresponding permeability values.