US-12617524-B2 - Uplock unlock electro-hydrostatic actuator

US12617524B2US 12617524 B2US12617524 B2US 12617524B2US-12617524-B2

Abstract

An electrohydrostatic actuator (EHA) for unlocking a uplock of an aircraft is provided, the EHA includes a solenoid, a plunger, a first manifold, and an unlock mechanism. The plunger is mechanically coupled to the solenoid. Responsive to the solenoid being energized, the solenoid is configured to translate the plunger in a first direction to push a hydraulic fluid into the first manifold that feeds the unlock mechanism. Responsive to a command to unlock the uplock of the aircraft, the hydraulic fluid is pushed to the unlock mechanism thereby causing the unlock mechanism to maneuver an over-centered mechanism over a centerline and unlock a uplocked landing gear.

Inventors

Jason Bradley Allen

Assignees

GOODRICH CORPORATION

Dates

Publication Date: 20260505
Application Date: 20240404

Claims (16)

1 . An electrohydrostatic actuator (EHA) for unlocking an uplock of an aircraft, the EHA comprising: a solenoid; a primary plunger positioned within the solenoid; a secondary plunger positioned within a first chamber separate from the solenoid, wherein the secondary plunger is mechanically coupled to the primary plunger within the solenoid via a shaft; a first manifold, wherein the first manifold is fluidly coupled to the first chamber; an extension, wherein: a first end of the extension is mechanically coupled to the secondary plunger, a second end of the extension is positioned within a second chamber, and the first manifold is fluidly coupled to the second chamber; and an unlock mechanism, wherein, responsive to the solenoid being energized, the solenoid is configured to translate the primary plunger in a first direction to push a hydraulic fluid within the first chamber, via the secondary plunger, into the first manifold, via a first check valve, that feeds the unlock mechanism and, at a same time, translate the extension in the first direction to push hydraulic fluid within the second chamber, via the extension, into the first manifold, via a second check valve, that feeds the unlock mechanism, and wherein, responsive to a command to unlock the uplock of the aircraft, the hydraulic fluid in the first manifold is pushed to the unlock mechanism, thereby causing the unlock mechanism to maneuver an over-centered mechanism over a centerline and unlock an uplocked landing gear.
2 . The EHA of claim 1 , further comprising: an unloading valve; and a reservoir, wherein, responsive to a pressure in the first manifold exceeding predetermined pressure, the unloading valve redirects a portion of the hydraulic fluid in the first manifold to the reservoir.
3 . The EHA of claim 2 , further comprising: a second manifold, wherein the unloading valve redirects the portion of the hydraulic fluid in the first manifold to the reservoir via the second manifold.
4 . The EHA of claim 3 , further comprising: wherein, responsive to the command to unlock the uplock of the aircraft ending, pushing the hydraulic fluid in the reservoir into at least one of the first chamber or the second chamber while the secondary plunger is being spring-returned to a first position from a second position in a second direction opposite the first direction.
5 . The EHA of claim 1 , further comprising: an accumulator, wherein the accumulator is fluidly coupled to the first manifold, and wherein, responsive to a command to charge the accumulator, the hydraulic fluid in the first manifold is pushed to the accumulator.
6 . The EHA of claim 5 , wherein, responsive to the command to unlock the uplock of the aircraft, the hydraulic fluid from the accumulator is pushed to the unlock mechanism thereby causing the unlock mechanism to maneuver the over-centered mechanism over the centerline and unlock the uplocked landing gear.
7 . The EHA of claim 1 , further comprising: a relief valve; and a reservoir, wherein the relief valve is configured to open in response to an overload pressure in the first manifold, and wherein, responsive to the relief valve opening in response to the overload pressure, an excess hydraulic fluid in the first manifold is released into the reservoir.
8 . The EHA of claim 1 , further comprising: a directional valve, wherein the command to unlock the uplock of the aircraft activates the directional valve so that the hydraulic fluid in the first manifold is pushed to the unlock mechanism.
9 . An aircraft, the aircraft comprising: a landing gear; and an electrohydrostatic actuator (EHA) for unlocking the landing gear in an uplocked position, the EHA comprising: a solenoid; a primary plunger positioned within the solenoid; a secondary plunger positioned within a first chamber separate from the solenoid, the secondary plunger is mechanically coupled to the primary plunger within the solenoid via a shaft; a first manifold; an extension, wherein: a first end of the extension is mechanically coupled to the secondary plunger, a second end of the extension is positioned within a second chamber, and the first manifold is fluidly coupled to the second chamber; and an unlock mechanism, wherein, responsive to the solenoid being energized, the solenoid is configured to translate the primary plunger in a first direction to push first hydraulic fluid within the first chamber, via the secondary plunger, into the first manifold, via a first check valve, that feeds the unlock mechanism and, at a same time, translate the extension in the first direct direction to push a second hydraulic fluid within the second chamber, via the extension, into the first manifold, via a second check valve, that feeds the unlock mechanism, and wherein, responsive to a command to unlock an uplock of the aircraft, the first hydraulic fluid and the second hydraulic fluid are pushed to the unlock mechanism thereby causing the unlock mechanism to maneuver an over-centered mechanism over a centerline and unlock an uplocked landing gear.
10 . The aircraft of claim 9 , wherein the EHA further comprises: an unloading valve; and a reservoir, wherein, responsive to a pressure in the first manifold exceeding predetermined pressure, the unloading valve redirects a portion of the hydraulic fluid in the first manifold to the reservoir.
11 . The aircraft of claim 10 , wherein the EHA further comprises: a second manifold, wherein the unloading valve redirects the portion of the hydraulic fluid in the first manifold to the reservoir via the second manifold.
12 . The aircraft of claim 11 , wherein the EHA further comprises: wherein, responsive to the command to unlock the uplock of the aircraft ending, pushing the hydraulic fluid in the reservoir into at least one of the first chamber or the second chamber while the secondary plunger is being spring-returned to a first position from a second position in a second direction opposite the first direction.
13 . The EHA of claim 9 , wherein the EHA further comprises: an accumulator, wherein the accumulator is fluidly coupled to the first manifold, and wherein, responsive to a command to charge the accumulator, the hydraulic fluid in the first manifold is pushed to the accumulator.
14 . The aircraft of claim 13 , wherein, responsive to the command to unlock the uplock of the aircraft, the hydraulic fluid from the accumulator is pushed to the unlock mechanism thereby causing the unlock mechanism to maneuver the over-centered mechanism over the centerline and unlock the uplocked landing gear.
15 . The aircraft of claim 9 , wherein the EHA further comprises: a relief valve; and a reservoir, wherein the relief valve is configured to open in response to an overload pressure in the first manifold, and wherein, responsive to the relief valve opening in response to the overload pressure, excess hydraulic fluid in the first manifold is released into the reservoir.
16 . The aircraft of claim 9 , wherein the EHA further comprises: a directional valve, wherein the command to unlock the uplock of the aircraft activates the directional valve so that the hydraulic fluid is pushed to the unlock mechanism.

Description

FIELD The present disclosure relates to landing gear, and more specifically, to an electro-hydrostatic actuator for unlocking an uplock mechanism that retains the landing gear in a up position. BACKGROUND Landing gear actuation systems generally utilize hydraulic components that work with a central or a localized hydraulic system. As aircraft become more advanced there is a need for an electric landing gear actuation system that does not use a hydraulic system. SUMMARY An electrohydrostatic actuator (EHA) is provided for unlocking a uplock of an aircraft. The EHA includes a solenoid, a plunger, a first manifold, and an unlock mechanism. The plunger is mechanically coupled to the solenoid. Responsive to the solenoid being energized, the solenoid is configured to translate the plunger in a first direction to push a hydraulic fluid into the first manifold that feeds the unlock mechanism. Responsive to a command to unlock the uplock of the aircraft, the hydraulic fluid is pushed to the unlock mechanism, thereby causing the unlock mechanism to maneuver an over-centered mechanism over a centerline and unlock a uplocked landing gear. In various embodiments, wherein the plunger is positioned within a first chamber. In various embodiments, the first manifold is fluidly coupled to the first chamber. In various embodiments, the hydraulic fluid comprises a first portion and a second portion. In various embodiments, a translation of the plunger in the first direction pushes the first portion of the hydraulic fluid to the first manifold. In various embodiments, the EHA further includes an extension. In various embodiments, a first end of the extension is mechanically coupled to the plunger. In various embodiments, a second end of the extension is positioned within a second chamber. In various embodiments, the first manifold is fluidly coupled to the second chamber. In various embodiments, the translation of the plunger in the first direction translates the extension in the first direction. In various embodiments, a translation of the extension in the first direction pushes the second portion of the hydraulic fluid into the first manifold. In various embodiments, the EHA further includes an unloading valve and a reservoir. In various embodiments, responsive to a pressure in the first manifold exceeding predetermined pressure, the unloading valve redirects the second portion of the hydraulic fluid to the reservoir. In various embodiments, the EHA further includes a second manifold. In various embodiments, the unloading valve redirects the second portion of the hydraulic fluid to the reservoir via the second manifold. In various embodiments, responsive to the command to unlock the uplock of the aircraft ending, pushing the hydraulic fluid in the reservoir into at least one of the first chamber or the second chamber while the plunger is being spring-returned to a first position from a second position in a second direction opposite the first direction. In various embodiments, further includes an accumulator. In various embodiments, the accumulator is fluidly coupled to the first manifold. In various embodiments, responsive to a command to charge the accumulator, the hydraulic fluid is pushed to the accumulator. In various embodiments, responsive to the command to unlock the uplock of the aircraft, the hydraulic fluid from the accumulator is pushed to the unlock mechanism thereby causing the unlock mechanism to maneuver the over-centered mechanism over the centerline and unlock the uplocked landing gear. In various embodiments, the EHA further includes a relief valve and a reservoir. In various embodiments, the relief valve is configured to open in response to an overload pressure in the first manifold. In various embodiments, responsive to the relief valve opening in response to the overload pressure, an excess hydraulic fluid is released into the reservoir. In various embodiments, the EHA further includes a directional valve. In various embodiments, the command to unlock the uplock of the aircraft activates the directional valve so that the hydraulic fluid is pushed to the unlock mechanism. Also disclosed herein is an aircraft. The aircraft includes a landing gear and an electrohydrostatic actuator (EHA) for unlocking the landing gear in an uplocked position. The EHA includes a solenoid, a plunger, a first manifold, and an unlock mechanism. The plunger is mechanically coupled to the solenoid. Responsive to the solenoid being energized, the solenoid is configured to translate the plunger in a first direction to push a hydraulic fluid into the first manifold that feeds the unlock mechanism. Responsive to a command to unlock the uplock of the aircraft, the hydraulic fluid is pushed to the unlock mechanism, thereby causing the unlock mechanism to maneuver an over-centered mechanism over a centerline and unlock a uplocked landing gear. In various embodiments, wherein the plunger is positioned within a first chamber. In various em