Torque-sensitive locking and release mechanism for a bistable pitch propeller

Patent metadata

Field	Value
Publication number	US-10457381-B2
Application number	US-201715714595-A
Country	US
Kind code	B2
Filing date	Sep 25, 2017
Priority date	Mar 20, 2017
Publication date	Oct 29, 2019
Grant date	Oct 29, 2019

Abstract

A bistable pitch propeller includes a ball, a spring, and a clutch module where the clutch module has a range of rotational movement between a locked end position and a released end position. The clutch module includes a detent, where the ball sits inside and outside of the detent when the clutch module is in the locked end position and released end position, respectively. In response to an input torque and a spring force from the spring, the clutch module rotates toward the released end position and the locked end position, respectively. The bistable pitch propeller also includes an aircraft blade where the aircraft blade is at the first pitch angle and the second pitch angle when the clutch module is in the locked end position and the released end position, respectively.

First claim

What is claimed is:

1. A bistable pitch propeller, comprising:
a ball;
a spring;
a clutch module, wherein:
the clutch module has a range of rotational movement between a locked end position and a released end position;
the clutch module includes a detent, the ball sits in the detent when the clutch module is in the locked end position, and the ball sits outside of the detent when the clutch module is in the released end position;
the clutch module rotates toward the released end position in response to an input torque; and
the clutch module rotates toward the locked end position in response to a spring force from the spring; and

an aircraft blade, wherein:
the aircraft blade has a range of rotational movement between a first pitch angle and a second pitch angle;
the aircraft blade is mechanically coupled to the clutch module;
the aircraft blade is at the first pitch angle when the clutch module is in the locked end position; and
the aircraft blade is at the second pitch angle when the clutch module is in the released end position.

2. The bistable pitch propeller recited in claim 1 , wherein the detent is located on a planar surface of the clutch module that is perpendicular to the axis of rotation of the clutch module.

3. The bistable pitch propeller recited in claim 1 , wherein the detent is located on a non-planar surface of the clutch module.

4. The bistable pitch propeller recited in claim 1 , wherein:
the detent is located on a non-planar surface of the clutch module; and
the detent includes a curved detent which includes a curved surface that the ball rolls up as the clutch module rotates toward the released end position.

5. The bistable pitch propeller recited in claim 1 , wherein:
the detent is located on a non-planar surface of the clutch module;
the detent includes a curved detent which includes a curved surface that the ball rolls up as the clutch module rotates toward the released end position; and
the clutch module is stopped at the released end position when the ball is pressed between an inside of a cover and the curved surface of the detent.

6. The bistable pitch propeller recited in claim 1 , wherein:
the detent is located on a non-planar surface of the clutch module; and
the spring is a clutch plate spring; and
the bistable pitch propeller further includes a ball spring which pushes the ball radially inward towards the center of the clutch module.

Assignees

• Kitty Hawk Corp

Inventors

• Kuentzel Steffen
• Vander Lind Damon

Classifications

• B64C29/0033

  the propellers being tiltable relative to the fuselage · CPC title

• F05D2260/79

  Bearing, support or actuation arrangements therefor · CPC title

• F04D15/0055

  Rotors with adjustable blades · CPC title

• F16D43/206

  moving axially between engagement and disengagement · CPC title

• B63H3/002

  with individually adjustable blades · CPC title