Speed Control Assembly and Methods of Using Same

Patent metadata

Field	Value
Publication number	US-2015274287-A1
Application number	US-201414202826-A
Country	US
Kind code	A1
Filing date	Mar 10, 2014
Priority date	Mar 15, 2013
Publication date	Oct 1, 2015
Grant date	—

Abstract

A speed control assembly includes an input drive shaft coupled to a first gear subassembly having a rotatable gear, a second gear subassembly coupled to an output drive shaft, and a linkage coupling the first and second gear subassemblies, wherein the input drive shaft, the first and second gear subassemblies, and the linkage are configured such that a rotational speed of the rotatable gear adjusts a ratio of a rotational speed of the output drive shaft to a rotational speed of the output drive shaft. In some embodiments, the first gear subassembly includes a sun gear coupled to the input drive shaft, one or more planet gears, and a ring gear as the rotatable gear. In some embodiments, the second gear subassembly includes a sun gear coupled to the output drive shaft, one or more planet gears, and a fixed ring gear.

First claim

What is claimed is:

1 . A speed control assembly, comprising:
an input drive shaft coupled to a first gear subassembly comprising a rotatable gear; a second gear subassembly coupled to an output drive shaft; and a linkage coupling the first gear subassembly to the second gear subassembly, wherein the input drive shaft, the first gear subassembly, the second-gear subassembly, and the linkage are configured such that a rotational speed of the rotatable gear adjusts a ratio of a speed of the output drive shaft to a speed of the input drive shaft.

2 . The assembly of claim 1 , wherein the first gear subassembly comprises a first epicyclic gear subassembly comprising a sun gear coupled to the input drive shaft, one or more planet gears, and the rotatable gear, and wherein, the rotatable gear comprises a ring gear of the first epicyclic gear subassembly.

3 . The assembly of claim 2 , further comprising a counter-rotation device coupled to the ring gear and configured to adjust a speed of counter-rotation of the rotatable gear relative to the sun gear coupled to the input drive shaft.

4 . The assembly of claim 2 , wherein the second gear subassembly comprises a second epicyclic gear subassembly comprising a sun gear coupled to the output drive shaft, one or more planet gears, and a fixed ring gear.

5 . The assembly of claim 4 , wherein the linkage comprises a first carrier coupled to each of the one or more planet gears of the first epicyclic gear subassembly and a second carrier coupled to each of the one or more planet gears of the second epicyclic gear subassembly.

6 . The assembly of claim 5 , wherein an intermediate shaft couples the first carrier to the second carrier.

7 . The assembly of claim 4 , wherein the linkage comprises a carrier, and wherein the carrier is coupled to each of the one or more planet gears of the first epicyclic gear subassembly on a first side of the carrier and to each of the one or more planet gears of the second epicyclic gear subassembly on a second side of the carrier.

9 . The method of claim 4 , wherein the linkage comprises one or more intermediate shafts, and wherein each of the one or more intermediate shafts couples a planet gear of the first epicyclic gear subassembly to a planet gear of the second epicyclic gear subassembly.

10 . The assembly of claim 1 , further comprising a rotation speed adjustment device coupled to the rotatable gear.

11 . The assembly of claim 1 , wherein the speed control assembly is configured to stop a rotation of the output drive shaft.

12 . The assembly of claim 1 , further comprising a tail rotor of a helicopter, wherein the tail rotor comprises two or more blades and is coupled to the output drive shaft.

13 . The method of claim 12 , further comprising a fuselage and an engine of the helicopter, and wherein the speed control assembly couples the engine to the tail rotor within the fuselage.

14 . A speed control assembly, comprising:
an input drive shaft coupled to one or more planet gears of a first epicyclic gear subassembly; an output drive shaft coupled to one or more planet gears of a second epicyclic gear subassembly; and a linkage coupling a ring gear of the first epicyclic gear subassembly to a ring gear of the second epicyclic gear subassembly, wherein the one or more planet gears of the first epicyclic gear subassembly are coupled to a rotatable sun gear and to the ring gear of the first epicyclic gear subassembly.

15 . A method of controlling the speed of an output drive shaft, comprising:
rotating an input drive shaft coupled to a gear subassembly comprising a rotatable ring gear, wherein an output drive shaft is mechanically coupled to the rotatable ring gear; and adjusting a drive speed ratio by controlling a rotational speed of the rotatable ring gear, wherein the drive speed ratio is the ratio of a rotational speed of the output drive shaft to a rotational speed of the input drive shaft.

16 . The method of claim 15 , wherein the rotatable ring rotates in a radial direction opposite to a rotational direction of the input drive shaft.

17 . The method of claim 15 , further comprising preventing rotation of the rotatable gear such that the rotational speed of the output drive shaft is about the same as the rotational speed of the input drive shaft.

18 . The method of claim 15 , wherein the input drive shaft is coupled to a transmission that is coupled to an engine and a helicopter main rotor,
wherein a helicopter tail rotor is coupled to the output drive shaft, and wherein rotating the rotatable gear in a radial direction opposite to a rotational direction of the input drive shaft slows a rotational speed of the output drive shaft.

19 . The method of claim 15 , wherein the output drive shaft is coupled to a tail rotor of a helicopter and further comprising adjusting the noise of the tail rotor by adjusting the drive speed ratio.

20 . The method of claim 15 , wherein the output drive shaft is coupled to an auxiliary rotor of a vehicle propulsion system and further comprising maneuvering the vehicle by adjusting the drive speed ratio.

Assignees

• Bell Helicopter Textron Inc

Inventors

• Robertson Daniel B
• Smith Dudley E
• Fenny Carlos A
• Riley Walter West

Classifications

• F16H3/724

  using externally powered electric machines · CPC title

• B64C27/12 Primary

  Rotor drives · CPC title

• F16H3/58

  with sets of orbital gears, each consisting of two or more intermeshing orbital gears · CPC title

• F16H3/44

  using gears having orbital motion · CPC title