Retention washers, propeller retention systems, and related methods

Patent metadata

Field	Value
Publication number	US-12104641-B2
Application number	US-202016909027-A
Country	US
Kind code	B2
Filing date	Jun 23, 2020
Priority date	Jun 23, 2020
Publication date	Oct 1, 2024
Grant date	Oct 1, 2024

Abstract

Retention washers include a washer body having a first side and a second side opposite the first side. The washer body has a perimeter having one or more lobes, and the retention washer further includes a multi-point star-shaped hole extending through the washer body from the first side to the second side. The retention washer is configured to maintain an installation torque of an installed nut when the retention washer is positioned such that the hole circumscribes the nut. Systems for retaining a propeller assembly on a shaft may include a nut installed on a bolt, and a retention washer positioned such that the hole of the retention washer circumscribes the nut, thereby limiting rotation of the nut with respect to the bolt and retaining the nut on the bolt. The system may include a circular array of nuts and bolts, each nut having a respective retention washer positioned thereon.

First claim

The invention claimed is:

1. A propeller assembly, comprising:
a plurality of studs;
a plurality of nuts, wherein each respective nut of the plurality of nuts is installed on a respective stud of the plurality of studs, wherein the plurality of nuts and the plurality of studs are configured to retain the propeller assembly on a shaft;
a plurality of retention washers, wherein each respective retention washer of the plurality of retention washers is positioned such that a hole of the respective retention washer circumscribes a respective nut of the plurality of nuts, such that the respective washer limits rotation of the respective nut with respect to a respective stud and retains the respective nut on the respective stud, wherein each retention washer comprises:
a washer body, comprising:
a first side; and
a second side opposite the first side, wherein the washer body has a perimeter having one or more lobes; and

the hole extending through the washer body from the first side to the second side, wherein the hole is a multi-point star-shaped hole, wherein each respective retention washer is configured to maintain an installation torque of the respective nut via engagement between the hole and the respective nut when the respective retention washer is positioned such that the hole circumscribes the respective nut; and

a hub assembly engaged with a propeller of the propeller assembly, wherein the hub assembly comprises a machined bore, wherein a portion of the perimeter of each retention washer of the plurality of retention washers is engaged with an internal surface of the machined bore such that the machined bore restricts rotation of each retention washer with respect to the hub assembly, and wherein the plurality of retention washers are configured to retain the hub assembly on a shaft of the propeller assembly.

2. The propeller assembly according to claim 1 , wherein each respective retention washer of the plurality of retention washers is configured to be translated axially along a longitudinal axis of the respective stud to position the respective retention washer on the respective nut.

3. The propeller assembly according to claim 1 , wherein the plurality of studs comprises a circular array of studs spaced circumferentially about the shaft.

4. The propeller assembly according to claim 1 , further comprising a snap ring engaged with the plurality of retention washers such that the snap ring is configured to restrict axial translation of the plurality of retention washers with respect to the hub assembly along a longitudinal axis of the shaft, wherein the snap ring is substantially annular and extends substantially around a circumference of the hub assembly, and wherein the snap ring engages the first side of each retention washer of the plurality of retention washers.

5. The propeller assembly according to claim 1 , wherein each nut of the plurality of nuts is a 12-point nut, wherein each retention washer of the plurality of retention washers is configured to maintain a prescribed torque on a respective nut of the plurality of nuts, wherein the prescribed torque is within 5% of the installation torque of the respective nut, and wherein each retention washer of the plurality of retention washers is configured to prevent rotation of the respective nut of more than 7.8 degrees with respect to a respective stud of the plurality of studs.

6. The propeller assembly according to claim 1 , wherein each retention washer of the plurality of retention washers is selectively removable to facilitate selective removal of the hub assembly from the shaft, and wherein each retention washer of the plurality of retention washers is selectively replaceable after selective removal.

7. The propeller assembly according to claim 1 , wherein each respective nut of the plurality of nuts is only engaged with the hole of a respective retention washer of the plurality of retention washers such that the respective nut does not engage or contact the first side or the second side of the respective retention washer.

8. A method of propeller retention, the method comprising:
applying a nut onto a stud within a predetermined range of a prescribed installation torque, wherein the nut and the stud retain a propeller assembly on a shaft; and
positioning a retention washer with respect to the nut such that a hole of the retention washer circumscribes the nut, thereby limiting rotation of the nut with respect to the stud and maintaining the nut at a torque within the predetermined range of the prescribed installation torque, wherein the positioning the retention washer comprises translating the retention washer axially along a longitudinal axis of the stud, and wherein the retention washer comprises:
a washer body, comprising:
a first side; and
a second side opposite the first side, wherein the washer body has a perimeter having at least a first lobe, a second lobe, and a third lobe, wherein the perimeter has a first radius of curvature corresponding to the first lobe, wherein the perimeter has a second radius of curvature corresponding to the second lobe, and wherein the perimeter has a third radius of curvature corresponding to the third lobe; and

the hole extending through the washer body from the first side to the second side, wherein the hole is a multi-point star-shaped hole, wherein the retention washer maintains an installation torque of the nut via engagement between the hole and the nut when the retention washer is positioned such that the hole circumscribes the nut, wherein a center point of the hole is closer to a first center of the first radius of curvature of the perimeter than to a second center of the second radius of curvature or to a third center of the third radius of curvature, and wherein the retention washer is selectively removable from the nut to facilitate selective removal of the nut, and wherein the retention washer is selectively replaceable after selective removal.

9. The method according to claim 8 , further comprising:
selectively removing the retention washer from the nut;
removing the propeller assembly from the shaft after the selectively removing the retention washer from the nut, wherein the propeller assembly is a first propeller assembly;
coupling a second propeller assembly to the shaft via the nut and the stud; and
replacing the retention washer onto the nut.

Assignees

• Insitu Inc
• Insitu Inc A Subsidiary Of The Boeing Company

Inventors

• Blundell Chad Nichols

Classifications

• F16B39/24

  by means of washers, spring washers, or resilient plates that lock against the object (locking to the screw-thread F16B39/14 {, F16B39/34}, F16B39/36) · CPC title

• F16B21/183

  internal, i.e. with spreading action · CPC title

• F16B43/003 Primary

  with a special hole shape in order to allow a quick mounting or dismounting of the washer, e.g. with a keyhole slot (F16B43/005 takes precedence) · CPC title

• F16B39/10 Primary

  by a plate, {spring, wire} or ring immovable with regard to the bolt or object {and mainly perpendicular to the axis of the bolt}(F16B39/08 takes precedence) · CPC title