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:
Oct. 13, 1981
Filed:
May. 30, 1979
Garnet M Williams, Edmonton, GB;
James E Hollis, Portsmouth, GB;
Ferraris Development and Engineering Company Limited, London, GB;
Abstract
A respirometer comprises a casing in which a circular chamber is formed. A rotor is mounted for rotation within the chamber and comprises vanes carried by a spindle. A circular wall of glass ceramic material closes an end of the chamber. A pair of aligned radial arms are carried by the spindle between the vanes and the circular wall. Each arm carries a samarium cobalt magnet and rotates with the spindle within a recess in the circular wall. One of the magnets has its north pole adjacent the circular wall and the other has its south pole adjacent the circular wall. A bistable Hall effect sensor is mounted on the opposite side of the circular wall from the rotor with its sensitive region in as close proximity to the rotational path of the magnets as dimensional accuracy will allow. The frequency of change in magnitude of the electrical potential output signal from the sensor is indicative of the rotational speed of the rotor spindle which in turn is indicative of the volume of air or gas flow through the chamber.