Lift fan clutch plate for protecting wear surfaces

Patent metadata

Field	Value
Publication number	US-2017314625-A1
Application number	US-201715450736-A
Country	US
Kind code	A1
Filing date	Mar 6, 2017
Priority date	Mar 7, 2016
Publication date	Nov 2, 2017
Grant date	—

Abstract

A clutch for a lift fan comprising at least one output shaft lug key positioned in a keyway of at least two output clutch plates and extending axially from one to the other of the two output clutch plates. The output shaft lug key couples the rotation of the output clutch plates to the rotation an output shaft and allows axial movement of the two output clutch plates relative the output shaft lug key. The output shaft has an outer radial surface and an oppositely disposed inner radial surface, and the inner surface of the output shaft lug key extends radially to the seat of the keyway.

First claim

What we claim is:

1 . A clutch for a lift fan having;
a rotatable input shaft and a rotatable output shaft having a common axis of rotation; two substantially disc shaped output clutch plates oriented normal to the axis, each of the two output clutch plates having a keyway extending radially inward from a mouth at an outer diameter of the output clutch plate to a seat at an inner diameter of the output clutch plate; at least one output shaft lug key positioned in the keyway of the two output clutch plates and extending axially from one of the two output clutch plates to the other of the two output clutch plates, the output shaft lug key coupling the rotation of the output clutch plates to the rotation the output shaft and allowing axial movement of the two output clutch plates relative the output shaft lug key, the output shaft having an outer radial surface and an oppositely disposed inner radial surface; at least one input clutch plate positioned axially between the two output clutch plates, wherein the input clutch plate is rotationally fixed to the input shaft; wherein in an engaged position, the two output clutch plates are in frictional communication with the input clutch plates and a load is transferred from the input shaft to the output shaft via the two output clutch plates, the input clutch plates and the output shaft lug key; wherein in a disengaged position, each of the two output clutch plates are axially displaced from input clutch plate; and wherein the inner surface of the output shaft lug key extending radially to the seat of the keyway.

2 . The clutch of claim 1 , wherein the inner surface of the output shaft lug key is semi-circular and corresponds to a semi-circular keyway seat.

3 . The clutch of claim 1 , wherein the inner surface of the output shaft lug key is planar and corresponds to a planer keyway seat.

4 . The clutch of claim 1 , wherein the cross section of the inner surface of the shaft lug key and the cross section of the seat of the keyway is selected from the group consisting of a trapezoidal, parabolic, rectangular, triangular, chinned and polygonal shape.

5 . The clutch of claim 1 wherein the lug key fully fills the keyway.

6 . The clutch of claim 1 wherein the lug key further comprises one or more engagement protrusions.

7 . The clutch of claim 6 wherein said engagement protrusions are configured to mate with a portion of one or more of the at least one input clutch plate.

8 . The clutch of claim 1 wherein said lug key further comprises a coating applied to the inner surface that engages the keyway.

9 . The clutch of claim 8 wherein said output clutch plates further comprise a coating applied to one or more surfaces of the keyway.

10 . The clutch of claim 9 wherein said output clutch plates further comprise a coating applied to one or more surfaces of the output clutch plate proximate the keyway.

11 . The clutch of claim 8 wherein said coating comprises one of ceramic, silicon carbide, carbide, and cerametallic.

12 . A clutch for a lift fan having;
a rotatable input shaft and a rotatable output shaft having a common axis of rotation; two substantially disc shaped output clutch plates oriented normal to the axis, each of the two output clutch plates having a keyway extending radially inward from a mouth at an outer diameter of the output clutch plate to a seat at an inner diameter of the output clutch plate; at least one output shaft lug key positioned in the keyway of the two output clutch plates and extending axially from one of the two output clutch plates to the other of the two output clutch plates, the output shaft lug key coupling the rotation of the output clutch plates to the rotation the output shaft and allowing axial movement of the two output clutch plates relative the output shaft lug key, the output shaft having an outer radial surface and an oppositely disposed inner radial surface; at least one input clutch plate positioned axially between the two output clutch plates, wherein the input clutch plate is rotationally fixed to the input shaft; wherein in an engaged position, the two output clutch plates are in frictional communication with the input clutch plates and a load is transferred from the input shaft to the output shaft via the two output clutch plates, the input clutch plates and the output shaft lug key; wherein in a disengaged position, each of the two output clutch plates are axially displaced from input clutch plate; and wherein the keyway in each of the two output clutch plate having a trapezoidal shape, with the mouth of the keyway wider than the seat, the keyway having planar sides intersecting the base of the seat at an obtuse angle, and the output shaft lug key having a complementary trapezoidal cross section, wherein the sides of the output shaft lug key are parallel with the sides of the keyway and the inner surface of the output shaft lug key is wider than the seat base of the keyway.

13 . The clutch of claim 12 wherein said lug key further comprises a coating applied to the inner surface that engages the keyway.

14 . The clutch of claim 12 wherein said output clutch plates further comprise a coating applied to one or more surfaces of the keyway.

15 . A clutch for a lift fan having;
a rotatable input shaft and a rotatable output shaft having a common axis of rotation; two substantially disc shaped output clutch plates oriented normal to the axis, each of the two output clutch plates having a keyway extending radially inward from a mouth at an outer diameter of the output clutch plate to a seat at an inner diameter of the output clutch plate; at least one output shaft lug key positioned in the keyway of the two output clutch plates and extending axially from one of the two output clutch plates to the other of the two output clutch plates, the output shaft lug key coupling the rotation of the output clutch plates to the rotation the output shaft and allowing axial movement of the two output clutch plates relative the output shaft lug key, the output shaft having an outer radial surface and an oppositely disposed inner radial surface; at least one input clutch plate positioned axially between the two output clutch plates, wherein the input clutch plate is rotationally fixed to the input shaft; wherein in an engaged position, the two output clutch plates are in frictional communication with the input clutch plates and a load is transferred from the input shaft to the output shaft via the two output clutch plates, the input clutch plates and the output shaft lug key; wherein in a disengaged position, each of the two output clutch plates are axially displaced from input clutch plate; and wherein the seat surface of the keyway on the output clutch plates is coated with a coating.

16 . The clutch of claim 15 , wherein the coating is a wear resistant material.

17 . The clutch of claim 16 , wherein the coating is silicon carbide.

18 . The clutch of claim 15 , wherein the coating is selected from the group consisting of carbides, ceramics and cerametallic.

19 . The clutch of claim 15 , wherein the coating is applied on the output clutch plate faces proximate the keyway.

20 . The clutch of claim 15 wherein said lug key further comprises a coating applied to the inner surface that engages the keyway.

Assignees

• Rolls Royce Corp

Inventors

• Bouton Matthew Tyler
• Beckner Kevin
• Copeland Andy
• Starr Matt
• Schwerin Doug
• Hassler Kyle

Classifications

• F16D13/683 Primary

  for clutches with multiple lamellae · CPC title

• F05D2220/90

  in vehicles adapted for vertical or short take off and landing (v/stol vehicles) · CPC title

• F16D2250/0046

  Coating · CPC title

• B64C29/0025

  the propellers being fixed relative to the fuselage · CPC title

• F16D13/52

  Clutches with multiple lamellae {; Clutches in which three or more axially moveable members are fixed alternately to the shafts to be coupled and are pressed from one side towards an axially-located member (F16D13/385 takes precedence)} · CPC title