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.

Date of Patent:
Jun. 01, 1976

Filed:

Aug. 04, 1975
Applicant:
Inventors:

Donald W Fowler, West Haven, CT (US);

Sean J O'Connor, Bristol, CT (US);

Assignee:

United Technologies Corporation, Hartford, CT (US);

Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B64C / ;
U.S. Cl.
CPC ...
244 / ; 244 1713 ; 244187 ; 244 78 ; 244 85 ; 416 31 ; 416 43 ;
Abstract

In a helicopter, a pilot-actuated lever controls, through linkage mechanisms, a servo valve to drive a hydraulic piston; the piston moves a swash plate which in turn controls movement of rotor blade pitch positioning mechanisms against the force of blade loading, caused by aerodynamic forces. Blade loading, heretofore monitored visually by the pilot on a cruise guide indicator instrument, is used herein to control a secondary input to the servo valve, thereby to alter the position linkage mechanism which causes the force of a spring attached thereto to impose a force on the collective pitch control for blade loadings in excess of one-third of maximum allowable blade loads, in a direction tending to drive the control to lower collective pitch (lower blade loading). This provides 'feel' to the pilot in proportion to blade loading when at critical magnitudes. A trim system is selectively actuatable to provide an input to the auxiliary valve which tends to maintain the collective pitch control in a selected position.


Find Patent Forward Citations

Loading…