# US 9,751,616 B1 · Methods and apparatus to retain a rotor blade

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- Number: US 9,751,616 B1
- Document ID: US9751616B1
- Status: Granted
- Kind: B1
- Application number: 13/659,194
- Filed: 2012-10-24
- Granted: 2017-09-05
- Earliest claimed: 2012-10-24
- Assignees: The Boeing Company
- Applicants: The Boeing Company
- Inventors: Adrian Stanescu; Donald Thomas Powell
- Web page: https://patentgrep.com/patent/US9751616B1

## CPC

- B64C 11/06: for variable-pitch blades
- B64C 11/04: Blade mountings
- B64C 11/30: Blade pitch-changing mechanisms
- B64C 11/32: mechanical
- F01D 5/30: Fixing blades to rotors; Blade roots {; Blade spacers}
- F04D 29/34: Blade mountings {(for axial flow compressors F04D29/322)}
- F04D 29/36: adjustable {(flexible blades F04D29/382)}
- F04D 29/362: {during rotation}
- B64D 2027/005: {Aircraft with an unducted turbofan comprising contra-rotating rotors, e.g. contra-rotating open rotors [CROR]}
- Y02T 50/60: Efficient propulsion technologies, e.g. for aircraft
- B64C: AEROPLANES; HELICOPTERS
- F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D)
- F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02)
- B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
- Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION

## Abstract

Methods and apparatus to retain a rotor blade are disclosed herein. An example apparatus includes a rotor blade coupled to a rotatable hub of an engine system. The rotor blade includes a root, a flange and a blade. The root and the flange are disposed inside a cowling, and the blade is disposed outside of the cowling. The example apparatus also includes a retainer disposed inside the cowling adjacent the flange. The flange is to engage the retainer to retain the rotor blade with the engine system.

## Claims

### Claim 1

An apparatus, comprising:
a rotor blade including a root having a first end and a second end opposite the first end, a flange and a blade coupled to the second end of the root, the first end of the root coupled to a rotatable hub of an engine system via a pitch mechanism, the flange extending from the root between the first end and the second end, the root and the flange disposed inside a cowling, the blade disposed outside of the cowling, the flange including a first hook extending outward from a first side of the root and upward toward the cowling; and
a retainer disposed inside the cowling adjacent the flange, the flange to engage the retainer to retain the rotor blade with the engine system.

### Claim 2 (depends on 1)

The apparatus of claim 1, wherein the retainer includes a groove to receive the first hook.

### Claim 3 (depends on 1)

The apparatus of claim 1, wherein the retainer comprises a ring coaxial with an axis of rotation of the cowling.

### Claim 4 (depends on 1)

The apparatus of claim 1, wherein the retainer defines an aperture through which a portion of the rotor blade is to extend.

### Claim 5 (depends on 1)

The apparatus of claim 1, wherein the retainer comprises a first ring and a second ring, the first ring disposed on a first side of the rotor blade, the second ring disposed on a second side of the rotor blade.

### Claim 6 (depends on 1)

The apparatus of claim 1, wherein the flange is spaced apart from the retainer.

### Claim 7 (depends on 1)

The apparatus of claim 1, wherein the retainer is coupled to the cowling.

### Claim 8 (depends on 1)

The apparatus of claim 1, wherein the flange is spaced apart from the blade to define a space to receive the retainer between the flange and the blade.

### Claim 9 (depends on 1)

The apparatus of claim 1, wherein the flange includes a second hook extending outward from a second side of the root and upward toward the cowling, the second side of the root opposite the first side of the root.

### Claim 10 (depends on 9)

The apparatus of claim 9, wherein the retainer includes a first ring and a second ring coaxial with the cowling, the first ring disposed adjacent the first side of the root and the second ring disposed adjacent the second side of the root, the first ring disposed between the first hook and the cowling and the second ring disposed between the second hook and the cowling.

### Claim 11 (depends on 10)

The apparatus of claim 10, wherein the first hook extends from the first side of the root further than the first ring and the second hook extends from the second side of the root further than the second ring.

### Claim 12

An apparatus, comprising:
a rotor blade to be coupled to an open fan engine system, the rotor blade including a root having a first end and a second end opposite the first end, a flange and a blade coupled to the second end of the root, the first end of the root to be coupled to a pitch mechanism of the open fan engine system, a portion of the flange coupled to the root between the first end and the second end and extending away from a longitudinal axis of the rotor blade, the flange including a first hook extending outward from a side of the root and upward toward a cowling, the flange to engage a portion of the open fan engine system if a portion of the rotor blade including the flange moves toward the portion of the open fan engine system.

### Claim 13 (depends on 12)

The apparatus of claim 12, wherein the flange comprises a second hook disposed on an opposite side of the rotor blade as the first hook.

### Claim 14 (depends on 12)

The apparatus of claim 12, wherein the flange is spaced apart from the blade to define a space between the flange and the blade to receive a retainer.

### Claim 15

A method, comprising:
coupling a first end of a root of a rotor blade to a rotatable hub and a pitch mechanism of an engine system, the root having a second end opposite the first end, the rotor blade including a flange disposed along the root between the first end and the second end, the flange including a first hook extending outward from a first side of the root and upward toward a rotatable cowling of the engine system; and
disposing a retainer adjacent the flange such that if a portion of the rotor blade including the flange moves away from the rotatable hub, the flange engages the retainer to retain the rotor blade with the engine system.

### Claim 16 (depends on 15)

The method of claim 15, wherein disposing the retainer adjacent the flange comprises disposing a first ring adjacent the flange.

### Claim 17 (depends on 16)

The method of claim 16, wherein disposing the retainer adjacent the flange comprises disposing a second ring adjacent the flange.

### Claim 18 (depends on 15)

The method of claim 15 further comprising coupling the flange to the rotor blade.

### Claim 19 (depends on 15)

The method of claim 15 further comprising coupling the retainer to the rotatable cowling.

### Claim 20 (depends on 15)

The method of claim 15 wherein coupling the root of the rotor blade to the rotatable hub comprises coupling the root to the pitch mechanism, the pitch mechanism to enable pitch rotation of the rotor blade.