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, 2016
Filed:
Mar. 11, 2011
John H. Hussey, St. Louis, MO (US);
Keith I. Hoemann, Fenton, MO (US);
John H. Hussey, St. Louis, MO (US);
Keith I. Hoemann, Fenton, MO (US);
Nidec Motor Corporation, St. Louis, MO (US);
Abstract
An HVAC system includes a heating/cooling element; an electric motor; a speed sensor; and a control device. The heating/cooling element includes a heating element, a cooling element, and heat exchangers. The motor has a rotatable shaft coupled with a blower wheel. The speed sensor senses a rotational speed of the motor shaft and the blower wheel and includes a magnet coupled with the motor shaft for rotation therewith; and a coil assembly mounted concentrically over the magnet and operable to generate an alternating signal when the magnet rotates relative to the coil. The alternating signal has an electrical characteristic that is generally proportional to the rotational speed of the shaft. The control device determines a rotational speed of the motor shaft and disables operation of the heating/cooling element when the alternating signal indicates that the rotational speed of the shaft drops below a minimum threshold speed.