US 2012/0230823 A1 · Dual Spring Rate Damper

Dual Spring Rate Damper

AssigneeBell Helicopter Textron Inc.

InventorsFrank B. Stamps, Michael R. Smith, Christopher M. Bothwell, Lawrence M. Corso, James L. Braswell, JR., David A. Popelka, Ernst C. Schellhase, Charles L. Hollimon, Thomas J. Newman, Bryan Baskin, Thomas C. Campbell, Daniel B. Robertson

Life of this patent

Estimating the term…

Abstract

A rotor hub and method to dampen a force exerted on a rotor hub by a rotor blade during flight. The rotor hub including a central member rotatably coupled to a rotor mast, a blade grip rigidly attached to a blade and movably coupled to the central member, and an adjustable damper operably associated with the blade grip. The method includes damping the force exerted on the rotor hub with the adjustable damper and selectively adjusting the adjustable damper between a first spring rate and a second spring rate.

Claims20

Dependent claims

A rotor hub, comprising:

a central member rotatably coupled to a rotor mast;
a blade grip rigidly attached to a blade and movably coupled to the central member;
and
an adjustable damper operably associated with the blade grip;
wherein the blade exerts a force on the central member during flight;
and
wherein the adjustable damper is adjusted between a first spring rate and a second spring rate to dampen the force exerted on the central member.

4 more elements

A rotor hub, comprising:

a central member rotatably coupled to a rotor mast;
a blade grip rigidly attached to a blade;
a blade strap movably coupled to the central member and securely coupled to the blade grip, the blade strap forming an opening;
an adjustable damper disposed within the opening of the blade strap;
and
a bearing disposed within the opening of the blade strap and attached to the adjustable damper;
wherein the blade grip movably couples to the central member via the blade strap;
wherein during flight the blade exerts a force on the rotor hub that passes through the bearing and is damped with the adjustable damper;
and
wherein the adjustable damper is adjusted during flight to dampen changes in the force exerted on the rotor hub.

7 more elements

Dependencies are inferred from the claim text.

Facts

Application

13/461,414Filed 1 May 2012

Priority

27 Aug 2003

Published

13 Sep 2012

Term ends

Not estimatedThe source records don’t support an estimate.

Classification9 codes

F16F 13/08
The damper being a fluid damper, e.g. the plastics spring not forming a part of the wall of the fluid chamber of the damper: the plastics spring…
B64C 27/35
Rotors: having elastomeric joints
B64C 27/39
Having articulated joints: with individually articulated blades, i.e. with flapping or drag hinges
B64C 27/51
Rotorcraft; Rotors peculiar thereto: damping of blade movements

Family

Application60/498,073Us provisional application · filed 27 Aug 2003

Application10/568,170Continuation · filed 13 Nov 2006

Application13/461,414Continuation

US 2007/0137956 A1Published application

US 8,181,755 B2Related patent

US 8,857,581 B2Related patent

US 2012/0230823 A1This patent

From the US filing history. Foreign family members aren’t listed.