Blade

Patent metadata

Field	Value
Publication number	US-10107136-B2
Application number	US-201514954087-A
Country	US
Kind code	B2
Filing date	Nov 30, 2015
Priority date	Dec 19, 2014
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

A turbomachine blade comprising a metallic leading edge having a weakened region extending in a spanwise direction; and a crack initiator for selectively initiating cracking of the metallic leading edge along the weakened region.

First claim

The invention claimed is:

1. A turbomachine blade comprising:
a metallic leading edge formed of at least two parts, the metallic leading edge having a bondline between the at least two parts, the bondline extending in a spanwise direction of the metallic leading edge; and
a crack initiator located on the bondline, the crack initiator configured to selectively initiate cracking of the metallic leading edge along the bondline.

2. The turbomachine blade according to claim 1 , wherein the crack initiator is provided at a tip of the turbomachine blade.

3. The turbomachine blade according to claim 1 , wherein the crack initiator comprises a leading edge cap positioned at a tip of the turbomachine blade.

4. The turbomachine blade according to claim 3 , wherein the cap is a wedge shaped insert having a reduced width in a direction from the tip of the turbomachine blade towards a root of the turbomachine blade, width being measured in a direction from a pressure side to a suction side of the blade.

5. The turbomachine blade according to claim 4 , wherein the wedge shaped insert comprises planar sides angled to reduce the width of the insert.

6. The turbomachine blade according to claim 4 , wherein the insert is shaped to converge towards the bondline.

7. The turbomachine blade according to claim 3 , wherein the cap is bonded to the metallic leading edge.

8. The turbomachine blade according to claim 4 , wherein the cap includes shoulders that are arranged such that, in a non-failure condition, the shoulders rest on a region of the metallic leading edge, the cap configured so as to shear from a remainder of the cap when a predetermined impact force is applied to the cap.

9. The turbomachine blade according to claim 1 , wherein the metallic leading edge includes two wings and a fore portion positioned between the two wings.

10. The turbomachine blade according to claim 1 , wherein the turbomachine blade comprises a composite core to which the metallic leading edge is attached.

11. The turbomachine blade according to claim 1 , wherein the turbomachine blade is a fan blade for a gas turbine engine.

12. A gas turbine engine comprising the turbomachine blade according to claim 1 .

Assignees

• Rolls Royce Plc

Inventors

• Benson Christopher

Classifications

• F05D2300/10

  Metals, alloys or intermetallic compounds · CPC title

• F01D21/045 Primary

  special arrangements in stators or in rotors dealing with breaking-off of part of rotor · CPC title

• F01D5/282

  Selecting composite materials, e.g. blades with reinforcing filaments · CPC title

• F02C7/05

  having provisions for obviating the penetration of damaging objects or particles · CPC title

• F01D5/147

  Construction, i.e. structural features, e.g. of weight-saving hollow blades (F01D5/148, F01D5/16 and F01D5/20 take precedence; blade shape F01D5/141; blades with cooling or heating channels or cavities F01D5/18; heating, heat-insulating or cooling means on blades F01D5/18) · CPC title