BR102018014563B1 - LOW PROFILE ELECTRO-HYDROSTATIC ACTUATOR, AIRCRAFT AND INTEGRATED ACCUMULATOR AND PIPING SYSTEM - Google Patents

Abstract

In general, certain examples of the present disclosure provide an electrohydrostatic actuator comprising a piston assembly and a hydraulic cylinder. The piston assembly, having a piston head and a piston rod extending from the piston head, is located and movable within the hydraulic cylinder. The hydraulic cylinder includes a hydraulic fluid chamber region including a piston side chamber and a rod side chamber, a reservoir for storing hydraulic fluid located within the hydraulic cylinder that is in fluid communication with the hydraulic fluid chamber region. hydraulic fluid. The electro-hydrostatic actuator includes a hydraulic pump system for moving hydraulic fluid in the reservoir and hydraulic fluid chamber region, the hydraulic pump system in fluid communication with a flow control network in a hydraulic cylinder boss for controlling a direction and magnitude of hydraulic fluid flow within the hydraulic fluid chamber region, and an electric motor for driving the hydraulic pump system.

Description

Background

[01] The present description generally refers to fluid pressure actuators and, more specifically, to electro-hydrostatic actuators. Electrohydrostatic actuators (EHAs) are known for powering aircraft operations such as flight control surfaces, landing gear retraction or extension, steering or braking, and lifting mechanisms for various vehicles. A typical EHA system includes multiple components, for example, an electric motor that drives a hydraulic pump to move hydraulic fluid from a reservoir to a hydraulic cylinder to drive the actuator. However, current component-based EHA systems are bulky, heavy, incurring a higher manufacturing cost, and require assembly and piping at the facility.

[02] Therefore, there is a need to create low-profile EHA containing all components in an integrated package and yet provide improved component durability for an extended hydraulic operational life.

summary

[03] Below, a simplified summary of the description is presented in order to provide a basic understanding of certain examples of the present description. This summary is not an extensive overview of the description and does not identify key/critical elements of the present description nor delineate the scope of the present description. Its sole purpose is to present some concepts described here in a simplified way as an introduction to the more detailed description that will be presented later.

[04] In general, certain examples of the present description provide electrohydrostatic actuators. According to various examples, an electrohydrostatic actuator is provided comprising a piston assembly having a piston head and a piston rod extending from the piston head, and a hydraulic cylinder, with the piston assembly located and movable. inside the hydraulic cylinder. The hydraulic cylinder includes a hydraulic fluid chamber region including a piston side chamber and a rod side chamber. The electro-hydrostatic actuator further comprises a reservoir for storing hydraulic fluid located within the hydraulic cylinder that is in fluid communication with the hydraulic fluid chamber region. The electro-hydrostatic drive further comprises a hydraulic pump system for moving hydraulic fluid in the reservoir and hydraulic fluid chamber region. The hydraulic pump system may be in fluid communication with a flow control network to control a direction and magnitude of flow of the hydraulic fluid within the hydraulic fluid chamber region. The electro-hydrostatic drive further comprises an electric motor located within a hydraulic cylinder to drive the hydraulic pump system.

[05] In some examples, the electro-hydrostatic actuator further comprises an integrated control module located within the hydraulic cylinder for receiving a control signal and converting the control signal into a set point value at which the electric motor drives the hydraulic pump system. In some examples, the electric motor rotates a fixed or variable angle swash plate to drive the hydraulic pump system. In some examples, the direction of hydraulic fluid flow is determined by a fixed or variable angle swash plate movement direction and the magnitude of hydraulic fluid flow in the hydraulic fluid chamber region is controlled by an angle through which the swash plate is tilted.

[06] In some examples, the electro-hydrostatic actuator further comprises an integrated control module located within the hydraulic cylinder to receive an electrical control signal that controls the direction of movement of the fixed or variable angle swash plate and the angle of fixed or variable angle swash plate tilt. In some examples, the hydraulic pump system comprises a hydraulic pump cylinder block that is rotatable within the electrohydrostatic driver. The hydraulic pump cylinder block may comprise a plurality of pistons that are movable by rotation of the fixed or variable angle swashplate. In some examples, the plurality of pistons are coupled to the swash plate and slide within the rotating hydraulic pump cylinder block along a direction of a central axis (X) of the electrohydrostatic actuator.

[07] In some examples, the electro-hydrostatic actuator additionally comprises a separation element located within the hydraulic cylinder that separates the reservoir into a compressed gas chamber area and a hydraulic fluid chamber area. In some examples, the separating element is a membrane. In some examples, the separating element has an accordion shape. In some examples, the separating element is movably disposed within the hydraulic cylinder.

[08] In some examples, the piston assembly is moved in a first direction from a retracted position to an extended position by pumping hydraulic fluid from at least one rod side chamber and the reservoir into the side chamber. piston and pushes fluid from the rod-side chamber into the reservoir. The piston assembly may be further moved in a second direction opposite to the first direction by pumping hydraulic fluid from at least one of the piston side chamber, and the reservoir of the rod side chamber and pushing the hydraulic fluid. from the piston side chamber into the reservoir.

[09] In some examples, the hydraulic pump system includes a valve plate. In some examples, a direction of flow of hydraulic fluid supplied to or returned to the hydraulic pump system is controlled by the valve plate. In some examples, the valve plate is mechanically secured to or integral with the hydraulic cylinder boss. In some examples, the valve plate is rotatable within the hydraulic cylinder boss. In some examples, the flow control network is integrated into the hydraulic cylinder boss.

[010] In some examples, the electric motor is a servo motor and the hydraulic pump system is a bidirectional positive displacement pump. In some examples, a position of the piston assembly within the hydraulic cylinder and the output force produced by the piston assembly are controlled by modulating one of: an electric servo motor speed, a positive displacement pump speed, or a combination of the same. In some examples, a piston assembly position and output force are controlled by changing a speed and direction of the servo motor.

[011] In some examples, the electrohydrostatic driver further comprises a thermal management system, the thermal management system arranged to surround thermal hot spots on an external periphery of the driver. In some examples, the electrohydrostatic driver further comprises a position sensor that monitors a position of the driver, wherein at least one of a speed and a direction of the electric motor is controlled in accordance with the position of the driver.

[012] In yet another example of the present description, an integrated accumulator and piping system of a hydrostatic actuator is provided. According to various examples, the integrated accumulator and piping system of a hydrostatic actuator comprises an inner surface surrounding an outer periphery of a housing of a hydraulic cylinder including a piston assembly, having a piston head and a piston rod connecting to each other. extending from the piston head. The housing may include a hydraulic fluid chamber region including a piston side chamber and a rod side chamber. The integrated accumulator and piping system further comprises an outer surface defining a reservoir between the inner surface and the outer surface, where the reservoir is in fluid communication with the hydraulic fluid chamber region; and a fluid flow control network in fluid communication with a hydraulic pump system of the driver to control a direction and magnitude of flow of the hydraulic fluid within the hydraulic fluid chamber region, where the hydraulic pump system moves the hydraulic fluid in the reservoir and hydraulic fluid chamber region.

[013] In some examples, the fluid flow control network comprises a valve plate disposed interfacing the hydraulic pump system, the hydraulic fluid chamber region, and the reservoir. In some examples, the valve plate is operated to control a direction of a fluid flow to or from the hydraulic pump system without changing a direction of a motor that drives the hydraulic pump system.

[014] In some examples, the integrated accumulator and piping system further comprises a separation element located within the inner surface and the outer surface, the separation element separates the reservoir into a compressed gas chamber area and a gas chamber area. of hydraulic fluid. In some examples, the integrated accumulator and piping system is integrated into the hydrostatic actuator.

[015] In yet another example of the present description, an aircraft is provided having an electro-hydrostatic actuator. According to various examples, the electrohydrostatic actuator comprises a piston assembly having a piston head and a piston rod extending from the piston head. The electrohydrostatic actuator may further comprise a hydraulic cylinder, with the piston assembly located and movable within the hydraulic cylinder. The hydraulic cylinder includes a hydraulic fluid chamber region including a piston side chamber and a rod side chamber. The electrohydrostatic actuator further comprises a reservoir for storing hydraulic fluid located within the hydraulic cylinder that is in fluid communication with the hydraulic fluid chamber region. The electrohydrostatic actuator may further comprise a hydraulic pump system for moving hydraulic fluid in the reservoir and hydraulic fluid chamber region. The hydraulic pump system may be in fluid communication with a flow control network to control a direction and magnitude of flow of the hydraulic fluid within the hydraulic fluid chamber region. The electro-hydrostatic actuator may further comprise an electric motor located within the hydraulic cylinder to drive the hydraulic pump system. The electrohydrostatic actuator may further comprise a rotating valve plate within the hydraulic cylinder boss.

[016] These and other examples are further described below with reference to the figures.

Brief Description of the Drawings

[017] The description can be better understood by reference to the following description taken into consideration in conjunction with the attached drawings, which illustrate particular examples of the present description.

[018] Figure 1 illustrates a cross-sectional view of an illustrative electro-hydrostatic actuator, according to one or more examples of the present description.

[019] Figure 2 illustrates an exploded perspective view of an illustrative electro-hydrostatic actuator, according to one or more examples of the present description.

[020] Figure 3 illustrates a fragmentary schematic view of an accordion assembly arranged within a reservoir of an illustrative electro-hydrostatic actuator, according to one or more examples of the present description.

[021] Figure 4 illustrates a fragmentary cross-sectional view of a pumping system disposed adjacent to a movable valve plate and in fluid communication with a flow control network of an electro-hydrostatic actuator, according to one or more examples of this description.

[022] Figure 5 illustrates a schematic view of various operating fluid paths of an illustrative electro-hydrostatic actuator, according to one or more examples of the present description.

[023] Figure 6 is a schematic illustration of an aircraft, according to one or more examples of the present description.

[024] Figure 7 is a block diagram of an aircraft production and service methodology that can utilize the methods and sets described here.

Detailed Description of Private Examples

[025] Reference will now be made in detail to some specific examples of the present description including the best ways contemplated by the inventors to carry out the present description. Examples of these specific embodiments are illustrated in the attached drawings. While the present description is described in conjunction with these specific examples, it will be understood that the present description should not be limited to the examples described. Rather, it is intended to cover alternatives, modifications and equivalences that may be included within the spirit and scope of the present description as defined by the appended claims.

[026] In the following description, numerous specific details are presented in order to provide an in-depth understanding of the present description. Particular examples of the present description may be implemented without some or all of these specific details. In other cases, well-known process operations have not been described in detail so as not to unnecessarily obscure the present description.

[027] Various techniques and mechanisms of the present description will sometimes be described in singular form for reasons of clarity. However, it should be noted that some examples include multiple interactions of a technique or multiple instances of a mechanism unless otherwise noted. For example, a system uses a processor in a variety of contexts. However, it will be appreciated that a system may utilize multiple processors while remaining within the scope of the present description unless otherwise noted. Additionally, the techniques and mechanisms of the present disclosure will sometimes describe a connection between two entities. It should be noted that a connection between two entities does not necessarily mean an unimpeded direct connection, as a variety of other entities may reside between the two entities. For example, a processor may be connected to memory, but it will be appreciated that a variety of bridges and controllers may reside between the processor and memory. Consequently, a connection does not necessarily mean an unimpeded direct connection unless otherwise noted.

[028] Additionally, it should be noted that as numerical references must identify the same structural elements, parts or surfaces consistently throughout all figures, as such elements, parts or surfaces can be additionally described or explained throughout the specification writing, of which this detailed description is an integral part. Unless otherwise indicated, the drawings should be read (e.g., cross-shading arrangement of parts, proportion, degree, etc.) in conjunction with the specification, and should be considered a part of the entire written description of this invention. As used in the following description, the terms "horizontal", "vertical", "left", "right", "up" and "down", as well as adjective and adverb derivatives thereof (e.g., "horizontally", " to the right", "upwards", etc.) simply refer to the orientation of the illustrated structure since the particular drawing figure is normally facing the reader. Similarly, the terms "in" and "out" generally refer to the orientation of a surface relative to its axis of elongation, or axis of rotation, as appropriate.

Overview

[029] The present description provides a low-profile electro-hydrostatic actuator containing a hydraulic actuator, a reservoir, an electric motor and a hydraulic pump driven by the electric motor to move hydraulic fluid from the reservoir to the hydraulic actuator for actuation. of the trigger.

[030] In some examples, the electrohydrostatic driver is adapted with a bidirectional pump system to eliminate interruption and reverse the direction of the electric motor. In some examples, the electrohydrostatic actuator is additionally fitted with a thermal management layer to maintain operating temperature.

Illustrative Modalities

[031] Figure 1 illustrates a cross-sectional view of an illustrative electro-hydrostatic actuator according to one or more examples of the present description. An electrohydrostatic actuator 100 is illustrated here to include a hydraulic cylinder 30 having a piston assembly 20 movably located within a hydraulic fluid chamber housing 30-A. The electrohydrostatic actuator 100 is generally cylindrical in shape with a first end 11A and an opposing second end 11B along a central axis X in line A-A. The piston assembly 20 is movably disposed within a hydraulic fluid chamber region 28 of the hydraulic cylinder 30 at end 11A. In various examples, the hydraulic cylinder 30-A comprises a piston assembly 20 within the hydraulic fluid chamber housing 30-A surrounding a hydraulic fluid chamber region 28. The piston assembly 20 comprises a piston head 26, a piston rod 22 extending from the piston head 26, and a rod end 24, with the rod end 24 operatively extending or retracting with respect to the end 11A. The piston head 26 divides the hydraulic fluid chamber region 28 of the hydraulic cylinder 30 into a piston side chamber 32 and a rod side chamber 34. The volume or size of the piston side chamber 32 and the piston side chamber 32 rod side 34 will vary based on the extension or retraction position of the piston assembly 20.

[032] The electrohydrostatic actuator 100 additionally includes an integrated control module 60, an electric motor 50, a pumping system 40 having a valve plate 44, a reservoir 36 and fluid communication with a flow control network 38 and the hydraulic fluid chamber region 28. The reservoir 36 and the hydraulic fluid chamber 28 may both be sealed by an end cap 30-C. The end cap 30-C can sealably engage the piston rod 22 allowing movement of the piston rod 22 along the X axis while preventing fluid from escaping from the reservoir 36 or hydraulic fluid chamber 28. outer periphery, the electrohydrostatic actuator 100 includes a thermal management layer 70 to dissipate generated operating heat and maintain operating temperature.

[033] The electric motor 50 is located adjacent to and operatively coupled to the pumping system 40 to drive the pumping system 40 in the first and second opposite rotation directions. The pump system 40 includes a first inlet and outlet port 43A, a second inlet and outlet port 43B, a pump drive shaft 47, and a rocker plate 42 operating a plurality of pump pistons 46 to change the displacement of the pump system 40. In some examples, the swash plate 42 may be a fixed swash plate. In other examples, the swashplates may be a variable angle swashplate.

[034] A first fluid passage 45A connects the first inlet and outlet port 43A and the piston side chamber 32. A second fluid passage 45B connects the second inlet and outlet port 43B and the rod side chamber 34 In several examples, the second fluid passage 45B is integrated into a portion of the hydraulic fluid chamber housing 30-A, as illustrated. A third fluid passage (not illustrated) returns leaked hydraulic fluid from pumping system 40 to reservoir 36 for accumulation purposes.

[035] The reservoir 36 is in fluid communication with the pump system 40, the flow control network 38, and the hydraulic fluid chamber region 28. As illustrated here, the flow control network 38 is integrated to an integrated hydraulic cylinder boss 39, such as hydraulic cylinder boss 211, further described below with reference to Figure 2. A membrane 330 is adapted within the reservoir 36, between a surface 332 of an inner periphery of a reservoir wall and a surface 334 of an outer periphery of the hydraulic fluid chamber housing. Membrane 330 provides reservoir 36 with amplified fluid pressure storage.

[036] The hydraulic fluid reservoir 36 is connected through a first control valve 322 to the first fluid passage 45A, and through a second control valve 324 to the second fluid passage 45B. As the pump system 40 supplies hydraulic fluid to the piston side chamber 32, the first control valve 322 closes the fluid passage within the reservoir 36. Conversely, as the piston rod 22 extends to discharge hydraulic fluid from the rod-side chamber 34, the second control valve 324 opens the fluid passage to the reservoir 36. Conversely, when the pump system 40 supplies hydraulic fluid to the rod-side chamber 34 and discharges the fluid from the piston side chamber 32, the control valve 322 opens into the reservoir 36 while the control valve 324 closes the passage into the reservoir 36.

[037] The piston assembly 20 is operable to extend or retract the piston rod 22 with respect to the hydraulic cylinder 30 at the first end 11A. The rod end 24 is typically in connection with an external load (not shown) to drive movement of the external load upon movement of the piston rod 22.

[038] As used here, the pump system 40 can be referred to as a rotating group. In various examples, a rotating group may comprise one or more of the following: a hydraulic pump cylinder block 41, one or more pump pistons 46, a swash plate 42, and the valve plate 44. The multiple pump pistons 46 may be coupled to the swash plate 42 which is configured at an angle about the X axis. As previously described, the swash plate 42 may be a fixed swash plate and configured at a fixed angle. Alternatively, the swash plate 42 may be a variable angle swash plate and the angle setting may be determined by a motorized adjustment 43, which may extend or retract based on a desired amount.

[039] Each pump piston 46 is situated within a chamber of the hydraulic pump cylinder block 41. The hydraulic pump cylinder block 41 may be the hydraulic pump cylinder block 214 described below. The electric motor 50 may be mechanically coupled to one or more components of the rotating group via the pump drive shaft 47. As the electric motor 50 is activated, it causes the pump drive shaft 47 to rotate the pump block. hydraulic pump cylinder 41 and the swash plate 42 with pump pistons 46, causing each pump piston 46 to cycle in their respective chambers within the hydraulic pump cylinder block 41. This drives the hydraulic pump system and causes fluid flows in and out of hydraulic cylinder 30.

[040] In some examples, the direction of hydraulic flow is determined by a direction of movement of the electric motor. In some examples, the direction of hydraulic flow is determined by a fixed or variable angle swash plate movement direction. For example, the piston rod 22 may extend along the central axis example, oil or the like, is supplied into the piston side chamber 32 and discharged from the rod side chamber 34. Conversely, the piston rod 22 may retract along the central axis 11B, when the electric motor 50 is operated to drive the pump system 40 in a second direction, causing hydraulic fluid to be supplied into the rod-side chamber 34 and discharged from the piston-side chamber 32.

[041] Various components and sealing mechanisms can be used to close the opening of the hydraulic fluid chamber region 28 located at the first end 11A, in addition to sealing the surrounding piston rod 22 projecting at the first end 11A. Various known sealing mechanisms for sealing the circumference of the piston head 26 can also be used to prevent hydraulic fluid between the piston side chamber 32 and the rod side chamber 34.

[042] In some other example, the electric motor 50 is an electric servo motor, and the pump system 40 is a bidirectional positive displacement hydraulic pump. Control of driver position, rate and output force is provided by at least one of modulating motor/pump speed and direction of change of motor/pump rotation. Where the pump system 40 is a bidirectional pump and has a first and second inlet and outlet ports 43A and 43B connected, respectively, to the first fluid passage 45A and second fluid passage 45B. The pump system 40 is operable in one direction to supply pressurized fluid from the first inlet and outlet port 43A to the piston side chamber 32 of the hydraulic fluid chamber region 28, while passing the fluid through the second port. fluid 45B from the rod side chamber 34 of the hydraulic fluid chamber region 28 to extend the piston rod 22 in a first direction. The pumping system 40 is also operable in a second direction opposite the first direction to supply pressurized fluid from the second inlet and outlet port 43B through the second fluid passage 45B to the rod side chamber 34 of the pressure chamber region. hydraulic fluid 28, while passing fluid through the first fluid passage 45A, from the piston side chamber 32 of the hydraulic fluid chamber region 28, to retract the piston rod 22 in a second direction, which is opposite to the first direction.

[043] Where the pump system 40 is a bidirectional pump, a pump system 40 may be any of several types of pumps suitable for moving hydraulic fluid in opposite directions through the ports to and from the piston side chamber 32 and rod-side chamber 34. When a servo-hydraulic pump such as the swash plate piston pump is used, hydraulic power is supplied by the combination of a unidirectional, constant-speed electric motor and the servo-hydraulic pump . For example, a servo pump may include a fixed swash plate or a variable angle swash plate for controlling the magnitude and direction of flow, with the direction of flow being determined by the direction of movement of the swash plate and the magnitude of flow being controlled. by the angle through which the swashplate is tilted. In this way, the reversal of the piston pitch can be carried out without interrupting and reversing the direction of the motor/pump.

[044] The flow of fluid from the pumping system 40, through the hydraulic cylinder boss 39, and entering the hydraulic cylinder 30, can be managed by the valve plate 44. In various examples, the valve plate 44 can have a series of kidney-shaped passages that are aligned with chambers within the pump cylinder block 41. The structure and operation of the valve plate 44 are further discussed below. In examples where the pump system 40 comprises a bidirectional pump, the swash plate 44 may be anchored and secured in a fixed position to the walls of the electro-hydrostatic apparatus 100. In some examples, the swash plate 44 may be anchored to the cylinder boss. hydraulic 39 in a fixed position.

[045] However, a bidirectional pump system 40 may incur additional load on the rotating group and reversing rotational movements may add more wear to components of the pump system 40, such as the motor 50 and other supports. Thus, in some examples, a unidirectional motor may be implemented as the motor 50. In such examples, the motor 50 rotates the pump drive shaft 47 and the rotating group in only one direction. It can be clockwise or counterclockwise. Thus, to successfully control the movement of fluid into and out of the hydraulic fluid chamber 28 and the reservoir 36, the swash plate 44 can be configured to rotate with respect to the hydraulic cylinder boss 39 and the rotating group. In various examples, the swash plate 44 may be rotated clockwise or counterclockwise to align its passages with particular chambers within the pump cylinder block 41 so that fluid can be pumped into and out of the passages. of the flow control network 38.

[046] The integrated control module 60, disposed at the second end 11B opposite the piston assembly, is adjacent to and operatively coupled to the pumping system 40. In some examples, the integrated control module 60 may be a electronic power control module. The integrated control module 60 sends control commands to components such as the pumping system 40, the motorized adjustment 43, the electric motor 50, and the valve plate 44. The integrated control module 60 also supplies electrical power from drive to the electric motor 50. Control commands are generated according to various signals recorded in the integrated control module 60. Such signals may be control signals from the external controller such as a vehicle management computer (VMC), or signals of engine speed, swash plate angle, piston assembly output force 20, or the like. For example, a position sensor 62 detects a position of the piston rod 22 and records the perceived position information as a signal in the integrated control module 60. In some examples, the integrated control module 60 converts the control signal into a set point value at which the electric motor 50 is commanded to drive the pumping system 40. As shown in Figure 1, the position sensor 62 may be one of several elements comprising the integrated control module 60. However, in As some examples, the position sensor 62 may be an integral part of the hydraulic cylinder boss, piston rod 22, or piston assembly 20.

[047] As illustrated here, the thermal management layer 70 is formed to enclose the outer periphery of the electro-hydrostatic actuator 100. In some examples, the thermal management chamber 70 is disposed around the outer periphery of the electro-hydrostatic actuator 100. hydrostatic actuator 100 in selective areas known for their heat dissipation needs, depending on the particular in-line configuration of the components of the electrohydrostatic actuator 100. For example, such heat sensitive areas may be surfaces corresponding to parts of the hydraulic cylinder 30, wherein at least one of the electric motor and the pump system is arranged. Such thermal management layer 70 can be made from any suitable material exhibiting high thermal conductivity. For example, thermal layer materials include, but are not limited to, metals, carbon, graphite, epoxy fibers, ceramics, metal matrix composites, carbon matrix composites (e.g., carbon and nickel nanoparticles that grow on carbon fibers), ceramic matrix composites or similar. In some examples, the thermal management layer 70 is treated with a metallic liner to prevent fluid permeation. In various examples, the hydraulic cylinder 30 may be made from any of suitable materials such as carbon fiber composites, high performance lightweight alloys.

[048] Figure 2 illustrates an exploded perspective view of an illustrative electro-hydrostatic actuator according to one or more examples of the present description. The electrohydrostatic actuator 200 has various components arranged in an in-line configuration along and around a central axis X on line B-B. In various examples, the electrohydrostatic actuator 200 may be the electrohydrostatic actuator 100. The electrohydrostatic actuator 200 comprises an integrated hydraulic cylinder 210. In some examples, the integrated hydraulic cylinder 210 may be the hydraulic cylinder 30, and includes a piston assembly 208 movably mounted within a piston assembly housing of an integrated hydraulic cylinder 210, with the piston rod end 202 extending to and retracting from a first end 200A. The integrated hydraulic cylinder 210 may be housed and enclosed within a reservoir enclosure 204 (or enclosure) having an accordion-type assembly enclosure (206) (or enclosure) configured therein, with further details being illustrated with reference to Figure 3 .

[049] The integrated hydraulic cylinder 210 may be coupled to the hydraulic cylinder boss 211. In some examples, the hydraulic cylinder boss 211 may be the hydraulic cylinder boss 39, and may include a flow control network (not illustrated ), such as the flow control network 38. In various examples, an electrohydrostatic driver can be configured to house single, double, triple or quadruple pumping systems depending on redundancy requirements. The flow control network (such as 38 or 420) within a hydraulic cylinder boss 211 may be configured to accommodate the particular flow configuration. The hydraulic cylinder boss 211 may connect to a valve plate 212 with an optional adapter plate 218 disposed therebetween. In some examples, the valve plate 212 may be integrated with the hydraulic cylinder boss 211 or machined as a separate part for assembly. The electrohydrostatic actuator 200 further includes a rotating group comprising a pump cylinder block 214 housing a plurality of pump pistons 216 coupled to a swash plate 224, a pump support 222 and a support rail 220. At a second end 200B, the electrohydrostatic actuator 200 includes an electric motor and control modules 230 (not illustrated separately). The control module at 230 may be integrated with the control module 60. The electric motor may be the electric motor 50.

[050] As illustrated here, with the in-line configuration of various components in the direction along and around the central X axis, the electrohydrostatic actuator 200 allows its center of gravity to be positioned at or near the central X axis to achieve better weight balance. Additionally, with the cylinder block 214 of the pump system also arranged around the central axis X, such a configuration also provides a rotational balance in the pump drive. Both contribute to improved satisfaction of various vibration demands for the electrohydrostatic drive 200.

[051] Figure 3 illustrates a fragmentary schematic view of an accordion assembly 351 arranged within a reservoir 360 of an illustrative electro-hydrostatic actuator, according to one or more examples of the present description. In some examples, the reservoir 360 may be the reservoir 36 previously described with reference to Figure 1. As illustrated herein, a reservoir 360 is formed between an inner surface 364A of a reservoir wall 364 (such as reservoir enclosure 204) and an outer surface 362A of an outer periphery 362A of a hydraulic piston assembly housing 362. In some examples, the inner surface 364A corresponds to the surface 332 described in Figure 1. In some examples, the outer surface 362A corresponds to the surface 334 described in figure 1.

[052] The reservoir 360 has its interior subdivided into two pressure compartments 350A and 350B by an accordion assembly 351 which is alternatively known as a separation element 351. In some examples, the separation element 351 is a metallic or non-metallic membrane , such as the membrane 330 depicted in Figure 1. In some other examples and as illustrated herein, the separating member 351 is a thin-walled metal concertina or non-metallic concertina, including an outer concertina 352 and an internal concertina 354. The concertina outer surface 352 is fitted to surround and support the inner surface 364A of the reservoir wall 364, while the inner accordion 354 is fitted to surround and support the outer surface 362A of the piston assembly housing 362. In some examples, as the accordion assembly 351 contracts and expands, it is adapted to slide along an outer periphery 362A of the piston assembly housing wall 362, and along an inner periphery 364A of the reservoir wall 364.

[053] Compartment 350A is located toward the piston rod end (not illustrated here) and compartment 350B is located toward the piston end (not illustrated here) and in fluid communication with a chamber region. hydraulic fluid and a flow control network. In some examples, compartment 350A is filled with a gas typically under high pressure to provide a pressure store.

[054] In some examples, the interior of the accordion assembly 351 is a pressure storage chamber 356 that can be filled with a gas under high pressure. Such gas may be nitrogen gas or any other inert gas. The concertina assembly 351 may take any suitable form such as a folded concertina, metal membrane, non-metallic membrane or the like.

[055] Figure 4 illustrates a fragmentary cross-sectional view of a pumping system disposed adjacent to a movable valve plate and in fluid communication with a flow control network of an illustrative electro-hydrostatic actuator according to one or more examples of this description. In various examples, the pumping system may be the pumping system 40 previously described with reference to Figure 1. As illustrated herein, the pumping system may be a variable displacement swash plate piston pump comprising a swash plate 408 and a plurality of pump pistons 406 housed within a pump cylinder block 402. In some examples, the swash plate 408, the pump pistons 406, and the pump cylinder block 402 comprise a rotating group and are contained within a pump housing 456. In various examples, the swash plate 408 may be a fixed or variable angle swash plate 408. The plurality of pump pistons 406 are mounted on the swash plate 408 in their respective piston shoe assemblies 407 to perform the axial slip in its respective pump cylinder.

[056] A valve plate 404 is disposed interfacing the pump cylinder block 402 and a flow control network 420 to provide fluid communication between the swash plate pump and an integrated hydraulic cylinder boss 421 (partially illustrated). . In various examples, the valve plate 404 defines a fluid inlet and a fluid outlet (further depicted in FIG. 5) that are connected through passages in a pump housing support plate 456 or pump cylinder block 402 to the pump inlet port 432 and pump outlet port 434, respectively. In some examples, the valve plate 404 may be anchored to the support plate or pump housing 456. In some examples, the support plate may be an integral part of the pump housing 456. However, in some examples, the valve 404 is anchored to or configured as an integral part of the integrated hydraulic cylinder boss 421. In some examples, the valve plate 404 is anchored in a fixed position and does not move. In some examples, the valve plate 404 may be a movable valve plate that can rotate to align one or more inlet and outlet ports with any combination of passages in a black plate and ports 432 and 434 of the pump cylinder block 402 .

[057] As partially illustrated here, a pump shaft 410, extending axially along the central axis its base (not illustrated) for rotation by an electric motor (not illustrated). The pump shaft 410 may be further mounted on suitable brackets 452-C in the pump housing 456. The pump cylinder block 402 is adapted to rotate with the pump shaft 410 and in sliding engagement against the valve plate 404. In For example, the hydraulic pump cylinder block 402 may be rotatably coupled to the valve plate 404 through shaft supports 452-B located within a support plate 454, which may facilitate sliding engagement against the valve plate. 404. In some examples, the support plate 454 may be an integral part of the pump cylinder block 402. In some examples, the support plate 454 may be an integral part of the valve plate 404. With the pump pistons 406 Arranged annularly around and parallel to the pump shaft 410, when the pump shaft 410 and the pump cylinder block 402 are rotated, the pump pistons 406 reciprocate axially through a pitch determined by the angular position of the swash plate. 408.

[058] The swash plate 408 is mounted for tilting movement between a zero displacement position in which the swash plate is normal with respect to the pump pistons 406, and a full forward or reverse displacement position in which the swash plate 408 is controlled to tilt in any direction of the central axis (e.g., the central axis can be tilted at different angles in various locations. In several examples, the swash plate 408 does not rotate together with the other components of the rotating group. However, the piston shoe assembly 407 can be rotated with the pump cylinder block 402 and the pump pistons 406 of the rotating group on a well-lubricated surface of the swash plate 408.

[059] The pump may include a bidirectional or unidirectional configuration. A bidirectional pump can be a bidirectional positive displacement pump, which can cause the rotating group to rotate in both a first direction and a second reverse direction to alternate the source of high-pressure and low-pressure hydraulic fluid. A fixed valve plate can be implemented in a bidirectional pump configuration. For example, in a bidirectional pump configuration, the valve plate 404 may be anchored in a fixed position to the hydraulic cylinder boss 421 and the direction of changing rotation of the rotating group causes varying hydraulic pressures at outlet/inlet ports. in valve 404. In a unidirectional pump configuration, the rotating group rotates in only one direction, which causes the high-pressure and low-pressure hydraulic fluid to be located in a relative part of the rotating group. A movable valve plate can be implemented with a unidirectional pump configuration. For example, a movable valve plate 404 may be rotatably situated within the hydraulic cylinder boss 421 and the movable valve 404 may be rotated to control the flow of hydraulic pressure.

[060] As previously described, in some examples, the swashplate 408 may be a fixed or variable angle swashplate. In a fixed displacement pump where the swash plate 408 is a fixed swash plate, the tilt angle and tilt direction do not vary and the hydraulic pressure in each pump chamber is equal at a particular position in the rotation of the rotating group. In a variable displacement pump, where the swash plate 408 is a variable angle swash plate, the tilt angle and tilt direction of the swash plate 408 can be controlled based on the flow demand of the hydraulic fluid. The implementation of a fixed swash plate and a variable angle swash plate is further discussed with reference to Figure 5. As part of the swash plate pump control, an integrated control module, such as control module 60, is located within of the hydraulic cylinder to receive an electrical control signal that controls the direction of movement of the swash plate and the tilt angle of the swash plate. In several examples, the direction of movement of the swash plate determines the direction of flow of the hydraulic fluid. Additionally, the magnitude of hydraulic fluid flow into the hydraulic fluid chamber region 458 is controlled by an angle by which the swash plate is tilted.

[061] The valve plate 404, disposed between the pump cylinder block 402 and the flow control network 420 of the hydraulic cylinder boss 421, can be anchored to the hydraulic cylinder boss 421 in a fixed position. In other examples, the valve plate 404 may be a bidirectional rotary valve plate. Valve plate 404 includes a first port 432 and a second port 434. In some examples, in association with rotation of the cylinder block 402 about the central axis pump 406 revolves around the central axis X and reciprocates in the direction along the central axis 434.

[062] In particular, when the swash plate 408 is tilted in a first direction, as shown in Figure 4, the first port 432 serves as a low pressure inlet, and the second port 434 as a high pressure outlet. In this operation, the low-pressure hydraulic fluid is sucked through a first fluid passage 438 through the first port 432 of the valve plate 404 to return to the pump cylinder block 402. The high-pressure fluid from the pump cylinder block 402 pump 402 is discharged through the second port 434 and into the second fluid passage 436 of the flow control network 420 to be supplied to the actuator hydraulic fluid chambers (not illustrated).

[063] Conversely, when the swash plate 408 is tilted in a second reverse direction, the second port 434 serves as a low pressure inlet, and the first port 432 as a high pressure outlet. In this operation, the low-pressure hydraulic fluid is sucked through a second fluid passage 436 through the second port 434 of the valve plate 404 to return to the pump cylinder block 402. The high-pressure fluid from the pump cylinder block 402 pump 402 is discharged through the first port 432 and through a first fluid passage 438 from the flow control network 420 to be supplied to the hydraulic fluid chambers of the driver (not illustrated).

[064] As illustrated here, a first check and anti-cavitation valve 426, a second check and anti-cavitation valve 422, and a switch valve 424 are disposed in the flow control network 420, details of which are described below with respect to the figure 5.

[065] Additionally, as illustrated here, a valve plate shaft 412 is configured to extend axially through a pump shaft hole 410 and mechanically coupled to the center of the valve plate 404. In association with rotation of the pump shaft valve plate 412, valve plate 404 is operated bidirectionally. In particular, when the valve plate shaft 412 rotates in a first direction, the valve plate 404 is rotated in the first direction to change the opening and closing of the first port 432 and second port 434. Conversely, when the valve plate shaft 412 valve plate 412 rotates in a second opposite direction, the valve plate 404 rotates in the second direction to change the opening and closing of the first port 432 and the second port 434.

[066] In some examples, the valve plate 404 is driven by a valve drive motor. In some other examples, the valve plate 404 is driven by a piezoelectric motor, which is disposed in the integrated hydraulic cylinder boss as a precision mechanism for driving the valve plate 404. In some examples, the valve plate 404 is machined as a separate piece and mechanically fixed to the hydraulic cylinder boss. In some other examples, the valve plate is machined as an integral part of the hydraulic cylinder boss.

[067] In further detail, the valve plate 404 is configured with multiple semicircular ports (kidneys) that control the inlet and outlet of fluid within the pump cylinder block 402. As the pump cylinder block 402 rotates in around the central axis the plurality of pistons 406 reciprocates axially about the central axis X.

[068] The axial movement of the pistons is sinusoidal, causing the pistons 406 to operate in an alternating manner. During the rising portion of the piston reciprocating cycle, the pistons 406 move toward the valve plate 404 and the fluid trapped between the closed surface of the valve plate 404 and the pistons 406 is vented to the pump discharge port through from one of the valve plate's semicircular ports - the fluid is then pushed or displaced through the valve plate's discharge port and pump housing.

[069] As the alternation cycle continues, the connection between the trapped fluid chamber and the pump discharge port is closed. Soon after, this same chamber becomes open to the pump's suction port. As the pistons 406 continue to precede around the axis of the cylinder block, they move away from the valve plate 404, thereby increasing the trapped volume of the chamber. As this occurs, fluid enters the chamber from the pump's suction port to fill the empty space. This process continues until piston 406 reaches the bottom of the toggle cylinder block. The connection between the pumping chamber and the suction port is closed. Shortly afterwards, the chamber opens to the discharge port again and the pumping cycle begins again.

[070] Figure 5 illustrates a schematic view of various operating fluid paths of an illustrative electro-hydrostatic actuator in accordance with one or more examples of the present description. As illustrated here, an external load (not illustrated) is operated to move in a direction along arrow line J away from the electrohydrostatic actuator 500, or in a direction along arrow line K toward the electrohydrostatic actuator 500. -hydrostatic 500. Piston assembly 502, having a piston head 502B and a piston rod end 502A, extends in a direction along arrow line I, and retracts in a direction along arrow line H In this way, hydraulic fluid movement passes through the fluid passages in response to four (4) modes of actuator operation: retracting against loads; retracting with loads, extending against loads and extending with loads.

[071] In particular, the valve plate 560 may be a fixed valve plate that is anchored in position. In order to retract the electro-hydrostatic actuator 500 causing the piston assembly 502 to move in the direction of arrow line H, the pump (not illustrated here) driven by a motor (not illustrated here) rotates a rotating group, as in pump system 40, in a direction along the curved arrow line A (clockwise in Figure 5) to cause high pressure hydraulic fluid to be discharged from the second (outlet) port 564 of the control plate. valve 560 through the first fluid passage 551 (along the direction of the arrow line C) and is supplied into a rod-side chamber 506. At the same time, with the second fluid passage 553 under lower pressure, the check and anti-cavitation valve 552 restricts uncontrolled fluid flow into the first fluid passage 551 by preventing it from leaking into the second fluid passage 553. Additionally, by use of the anti-cavitation valve 552, the risk of cavitation damage to the pump with respect to insufficient inlet pressure can be reduced. A check valve and anti-cavitation valve 552 between the first fluid passage 551 and the second fluid passage 553 causes hydraulic fluid to flow to the pump if the inlet pressure to the pump becomes too low during operation. .

[072] Conversely, in order to extend the hydraulic actuator 500 causing the piston assembly 502 to move in the direction of arrow line I, the pump (not illustrated here) driven by a motor (not illustrated here) rotates in a direction along the curved arrow line B (counterclockwise in figure 5) to cause high pressure hydraulic fluid to be discharged from the first port (inlet) 562 of the valve plate 560 through the second passage of fluid 553 (along the direction of arrow line E) and is supplied into a piston side chamber 504. At the same time, with the first passage of fluid 551 under lower pressure, the check valve and an - cavitation 554 restricts uncontrolled fluid flow into the second fluid passage 553 against leakage into the first fluid passage 551. Additionally, by use of the anti-cavitation valve 554, the risk of cavitation damage to the pump with respect to insufficient inlet pressure can be reduced. A check valve, from check and anti-cavitation valve 554, between the first fluid passage 551 and the second fluid passage 553 causes hydraulic fluid to flow to the pump if the inlet pressure to the pump becomes too low during the operation.

[073] Conversely, in order to extend the hydraulic actuator 500 causing the piston assembly 502 to move in the direction of arrow line I, the pump (not illustrated here) driven by a motor (not illustrated here) , rotates in a direction along the curved arrow line B (counterclockwise in Figure 5) to cause high-pressure hydraulic fluid to be discharged from the first (inlet) port 562 of the valve plate 560 through the second fluid passage 553 (along the direction of arrow line E) and is supplied into a piston side chamber 504. At the same time, with the first fluid passage 551 under lower pressure, the check valve and anti-cavitation valve 554 restricts uncontrolled fluid flow into the second fluid passage 553 by preventing it from leaking into the first fluid passage 551. Additionally, by use of the anti-cavitation valve 554, the risk of cavitation damage being caused to the pump with respect to to insufficient inlet pressure can be reduced. A check valve, from the check and anti-cavitation valve 554, between the first fluid passage 551 and the second fluid passage 553, causes hydraulic fluid to flow to the pump if the inlet pressure to the pump becomes too low. during operation.

[074] As illustrated, the piston partition 565 is aligned with the second port 564. The piston partitions 565 may correspond to a piston chamber of the pump cylinder block in which high pressure hydraulic fluid is being generated by a piston of bomb. The first port 562 and the second port 564 may be further aligned with additional piston partitions (not illustrated).

[075] In some examples, the pump system includes a third port (wrap drain) 568 through valve plate 560 to cause at least one of the bypass and control hydraulic fluid to flow through a third passage. of fluid 555 (along the direction of arrow line G) back to the fluid reservoir 508. Generally, the increased volume in fluid flow in the third port 568 may indicate at least one of a reduction in the efficiency of pump and parts worn out parts of the pump. Additionally, the fact that the degree of hydraulic fluid viscosity and the space between moving parts vary under different temperatures also contributes to the increased volume in fluid flow in the third port 568. In some examples, a pressure flow control valve and temperature compensated 558 is arranged on the third port 568 to provide a warning of when the third port 568 discharges a fluid stream of a volume that exceeds a specified limit.

[076] In some example, the fluid reservoir 508 includes an accordion 510 configured within it, between an inner periphery of the reservoir wall and an outer periphery of the piston assembly housing, to provide amplified pressure storage. As illustrated herein in Figure 5, a flow control network 550 includes the first fluid passage 551, the second fluid passage 553, the third fluid passage 555, the anti-cavitation valve check valve 552, the check valve 554, the switch valve 556, and the pressure and temperature compensated flow control valve 558. In some examples, the flow control network may be implemented as the flow control network 38 or Figure 1, or the flow control network 420 of Figure 4.

[077] In some examples, the electrohydrostatic actuator 500 additionally comprises a position sensor 520 that monitors a position of the piston assembly 502, according to which at least one of a speed and a direction of the electric motor of the actuator. electrohydrostatic actuator 500 is controlled according to the position of the piston assembly 502. In some examples, piston position signals generated by position sensor 520 are provided to the electrohydrostatic actuator control module 500 for control of at least one of the electric motor and the pumping system. In some examples, the position sensor is a linear variable differential transformer (LVDT).

[078] In some examples, a shuttle valve 556 is used to reduce the fluid flow required to extend an unequal area actuator so that reduced actuation force can be allowed in one direction. When the retract line is pressurized, the 556 shuttle valve switches to isolate the retract line from the extension line. When the extension line is pressurized, the 556 shuttle valve blocks the retraction line allowing flow from the retraction side of the piston to flow to the extension side.

[079] As previously described, the pump system can be a unidirectional system in which the rotating group can rotate in only one direction. A variable angle swash plate can be implemented in a unidirectional system and controlled to change hydraulic pressure at particular locations relative to the valve plate 560. A unidirectional pump system with a fixed or variable angle swash plate can also be implemented with a movable valve plate. In some examples, a movable valve plate may also be implemented in a bidirectional pump system.

[080] In some examples, the valve plate 560 may be a movable valve plate, and the movement of the valve plate 560 may be controlled by a valve shaft, such as a valve shaft 412. In such examples, the pump (not illustrated here) driven by a motor (not illustrated here) can rotate continuously in a single direction along arrow line A or B, curved. Since the pump rotates in a singular direction, high pressure fluid can be generated on one side of the pump and low pressure fluid can be generated on the other side of the pump based on the tilt of the swash plate (not pictured). In this way, the swash plate 560 can rotate on either curved arrow line A or B in order to align the first port 562 or the second outlet port 564 with the fluid passage 551 or 553 so that the high-flow fluid Pressure can pass from the piston chambers in a pump cylinder block through port 562 or 564 and into passage 551 or 553. Swashplate 560 can additionally or alternatively be aligned so that low-pressure fluid pressure can pass from fluid passage 551 or 553 through port 562 or 564 and into the piston chambers in the pump cylinder block.

[081] For example, based on the tilt angle of a swash plate, such as swash plate 408, high pressure fluid can be generated by the pump pistons of the pump cylinder block located at a point on the left side of the valve plate 560. The valve plate 560 can be rotated in the direction of arrow line A or arrow line B so that the first port 562 is aligned with the pump pistons generating the high pressure hydraulic fluid, allowing the high-pressure hydraulic fluid flows into the second passage 553 in the direction of arrow line E. This may cause the piston side chamber 504 to be filled with fluid and cause the driver to extend in the direction of the arrow line I. As another example, the valve plate 560 can be rotated so that a solid portion 563 can be aligned with the pump pistons generating high-pressure hydraulic fluid, thereby blocking the high-pressure fluid from entering the second passage. 553.

Examples of Aircraft and Methods of Aircraft Manufacturing and Operation

[082] To better understand the various aspects of implementing the described systems and techniques, a brief description of an aircraft and aircraft wing is now presented. Figure 6 is a schematic illustration of aircraft 600, according to some examples. As shown in Figure 6, the aircraft 600 is defined by a longitudinal axis (X axis), a lateral axis (Y axis), and a vertical axis (Z axis). In various examples, aircraft 600 comprises fuselage 650 with interior 670. Aircraft 600 includes wings 620 coupled to fuselage 650. Aircraft 600 may also include engines 630 supported by wings 620. In some examples, aircraft 600 additionally includes a number of high-level inspection systems such as the electrical inspection system 640 and the environmental inspection system 660. In other examples, any number of other inspection systems may be included.

[083] The aircraft 600 illustrated in figure 6 is an example of a vehicle whose components can be manufactured, modified or machined to include at least one of the actuators 100 and 200, according to the illustrative examples. Although an aerospace example is illustrated, the principles described here can be applied to other industries, such as the automotive industry. Accordingly, in addition to aircraft 600, the principles described herein may be applied to other vehicles, e.g., land vehicles, marine vehicles, space vehicles, etc.

[084] Examples of the present description may be described in the context of the method of manufacturing and servicing aircraft 700 as illustrated in Figure 7 and aircraft 600 as illustrated in Figure 6. During pre-production, the illustrative method 700 may include specification and design (block 704) of aircraft 600 and procurement of material (block 706). During production, manufacturing of components and subassemblies (block 708) and inspection system integration (block 710) of aircraft 600 may occur. The described devices and assemblies, and corresponding methods, may be used in any of specification and design (block 704) of at least one of aircraft 600, material procurement (block 706), component and subassembly manufacturing (block 708), and integration of inspection system (block 710) of aircraft 600.

[085] After that, aircraft 600 can undergo certification and distribution (block 712) to be placed into service (block 714). While in service, aircraft 600 may be scheduled for routine maintenance and service (block 716). Routine maintenance and service may include modification, reconfiguration, renovation, etc. of one or more aircraft inspection systems 600. The described devices and assemblies, and corresponding methods, may be used in any of certification and distribution (block 712), service (block 714), and routine maintenance and service (block 716 ).

[086] Each of the processes of illustrative method 700 can be performed by an inspection system integrator, a third party, or an operator (e.g., a customer). For purposes of this description, an inspection system integrator may include, without limitation, any number of aircraft manufacturers and primary inspection system subcontractors; a third party may include, without limitation, any number of vendors, subcontractors and suppliers; and an operator may be an airline, a leasing company, a military entity, service organization, and so on.

[087] Corresponding apparatus and methods illustrated or described here may be employed during any one or more of the stages of the manufacturing and service method (illustrative method 700). For example, components or subassemblies corresponding to component or subassembly manufacturing (block 708) may be manufactured or manufactured in a manner similar to components or subassemblies produced while aircraft 600 is in service (block 714). Furthermore, one or more exemplary apparatuses, methods or combinations thereof may be used during the production stages (block 708) and (block 710), for example, by substantially accelerating the assembly of or reducing the cost of aircraft 600. Similarly, one or more examples of the apparatus or method embodiments, or a combination thereof, may be used, for example, and without limitation, while the aircraft 600 is in at least one in-service situation (block 714) and in maintenance and service (block 716).

[088] Additionally, the description comprises examples in accordance with the following clauses:

[089] Clause 1. An electro-hydrostatic actuator, comprising: a piston assembly having a piston head and a piston rod extending from the piston head; a hydraulic cylinder, in which the piston assembly is located and is movable within the hydraulic cylinder, the hydraulic cylinder including a hydraulic fluid chamber region including a piston side chamber and a rod side chamber; a reservoir for storing hydraulic fluid located within the hydraulic cylinder that is in fluid communication with the hydraulic fluid chamber region; a hydraulic pump system for moving hydraulic fluid in the reservoir and the hydraulic fluid chamber region, the hydraulic pump system in fluid communication with a flow control network in a hydraulic cylinder boss for controlling a direction and magnitude of hydraulic fluid flow within the hydraulic fluid chamber region; and an electric motor located inside the hydraulic cylinder to drive the hydraulic pump system.

[090] Clause 2. Electro-hydrostatic actuator according to clause 1, further comprising an integrated control module located within the hydraulic cylinder for receiving a control signal and converting the control signal into a set point value in the which electric motor drives the hydraulic pump system.

[091] Clause 3. Electro-hydrostatic actuator, in accordance with clause 1, in which the electric motor rotates a fixed or variable angle swashplate to drive the hydraulic pump system.

[092] Clause 4. Electro-hydrostatic actuator according to clause 3, in which the direction of hydraulic fluid flow is determined by a fixed or variable angle swash plate movement direction and the magnitude of hydraulic fluid flow into the hydraulic fluid chamber region and controlled by an angle through which the swash plate is tilted;

[093] Clause 5. Electro-hydrostatic actuator in accordance with clause 4, further including an integrated control module located within the hydraulic cylinder for receiving an electrical control signal, which controls the direction of movement of the fixed-angle swash plate or variable and the tilt angle of the fixed or variable angle swash plate.

[094] Clause 6. Electro-hydrostatic driver according to claim 3, wherein the hydraulic pump system comprises a hydraulic pump cylinder block that is rotatable within the electro-hydrostatic driver, the hydraulic pump cylinder block comprising a plurality of pistons that are movable by rotation of the fixed or variable angle swashplate.

[095] Clause 7. Electro-hydrostatic driver according to clause 6, in which the plurality of pistons are coupled to the swash plate and slide within the hydraulic pump cylinder block along a direction of a central axis of the driver electro-hydrostatic.

[096] Clause 8. Electro-hydrostatic actuator, according to clause 1, further comprising a separation element located within the hydraulic cylinder that separates the reservoir into a compressed gas chamber area and a hydraulic fluid chamber area.

[097] Clause 9. Electro-hydrostatic actuator, according to clause 8, in which the separation element is a membrane.

[098] Clause 10. Electro-hydrostatic actuator, in accordance with clause 8, in which the separation element has an accordion shape.

[099] Clause 11. Electro-hydrostatic actuator, in accordance with clause 8, in which the separation element is movably arranged within the hydraulic cylinder.

[0100] Clause 12. Electro-hydrostatic actuator according to clause 1, in which the piston assembly is moved in a first direction from a retracted position to an extended position by pumping hydraulic fluid from at least one from the rod-side chamber and reservoir into the piston-side chamber and pushes fluid from the rod-side chamber into the reservoir, and where the piston assembly is moved in a second direction opposite to the first direction by pumping hydraulic fluid from at least one piston side chamber and the reservoir into the rod side chamber and pushing the hydraulic fluid from the piston side chamber into the reservoir.

[0101] Clause 13. Electro-hydrostatic actuator according to clause 1, in which the hydraulic pump system includes a valve plate.

[0102] Clause 14. Electro-hydrostatic actuator according to clause 13, in which a direction of flow of hydraulic fluid supplied by or returned to the hydraulic pump system is controlled by the valve plate.

[0103] Clause 15. Electro-hydrostatic actuator, according to clause 13, in which the valve plate is mechanically fixed to or integral to the hydraulic cylinder boss.

[0104] Clause 16. Electro-hydrostatic actuator, according to clause 13, in which the valve plate is rotatable within the hydraulic cylinder boss.

[0105] Clause 17. Electro-hydrostatic drive according to clause 1, in which the electric motor is a servomotor and the hydraulic pump system is a bidirectional positive displacement pump.

[0106] Clause 18. Electro-hydrostatic actuator, according to clause 17, in which a position of the piston assembly within the hydraulic cylinder and output force produced by the piston assembly are controlled by modulating one of: a speed of the electric servo motor, a speed positive displacement pump, or a combination thereof.

[0107] Clause 19. Electro-hydrostatic actuator according to clause 17, in which a position of the piston assembly and output force are controlled by changing a servomotor speed and direction.

[0108] Clause 20. Electro-hydrostatic actuator, according to clause 1, in which the flow control network is integrated into the hydraulic cylinder boss.

[0109] Clause 21. Electro-hydrostatic actuator, according to clause 1, further comprising a thermal management system, the thermal management system arranged to surround thermal hot spots on an external periphery of the actuator.

[0110] Clause 22. Electro-hydrostatic actuator according to clause 1, further comprising a position sensor that monitors a position of the actuator, wherein at least one of a speed and a direction of the electric motor is controlled in accordance with the trigger position.

[0111] Clause 23. An integrated accumulator and piping system of a hydrostatic actuator comprising: an inner surface surrounding an outer periphery of a housing of a hydraulic cylinder, the hydraulic cylinder including a piston assembly having a piston head and a rod piston rod extending from the piston head, the housing including a hydraulic fluid chamber region including a piston side chamber and a rod side chamber; an outer surface defining a reservoir between the inner surface and the outer surface, where the reservoir is in fluid communication with the hydraulic fluid chamber region; and a fluid flow control network in fluid communication with a hydraulic pump system of the driver to control a direction and magnitude of flow of the hydraulic fluid within the hydraulic fluid chamber region where the hydraulic pump system moves the fluid hydraulic fluid in the reservoir and the hydraulic fluid chamber region.

[0112] Clause 24. Integrated accumulator and piping system according to clause 23, in which the fluid flow control network comprises a valve plate disposed interfacing the hydraulic pump system, the hydraulic fluid chamber region and the reservoir.

[0113] Clause 25. Integrated accumulator and piping system in accordance with clause 24, in which the valve plate is operated to control a direction of a fluid flow from or to the hydraulic pump system without changing a direction of an engine that drives the hydraulic pump system.

[0114] Clause 26. Integrated accumulator and piping system in accordance with clause 23, further comprising a separation element located within the inner surface and outer surface, wherein the separation element separates the reservoir into a gas chamber area tablet and a hydraulic fluid chamber area.

[0115] Clause 27. Integrated accumulator and piping system in accordance with clause 23, in which the integrated accumulator and piping system is integrated within the hydrostatic drive.

[0116] Clause 28. An aircraft having an electrohydrostatic actuator comprising: a piston assembly having a piston head and a piston rod extending from the piston; a hydraulic cylinder, wherein the piston assembly is located and movable within the hydraulic cylinder, the hydraulic cylinder including a hydraulic fluid chamber region including a piston side chamber and a rod side chamber; a reservoir for storing hydraulic fluid located within the hydraulic cylinder that is in fluid communication with the hydraulic fluid chamber region; a hydraulic pump system for moving hydraulic fluid in the reservoir and hydraulic fluid chamber region, the hydraulic pump system in fluid communication with a flow control network in a hydraulic cylinder boss for controlling a direction and magnitude of flow of the hydraulic fluid within the hydraulic fluid chamber region; and an electric motor located inside the hydraulic cylinder to drive the hydraulic pump system.

[0117] Clause 29. The aircraft according to clause 28, in which the electro-hydrostatic actuator further comprises an integrated control module located within the hydraulic cylinder for receiving a control signal and converting the control signal into a value setting point at which the electric motor drives the hydraulic pump system.

[0118] Clause 30. The aircraft in accordance with clause 28 in which the electric motor rotates a fixed or variable angle swashplate to drive the hydraulic pump system.

[0119] Clause 31. The aircraft in accordance with clause 28, in which the direction of hydraulic fluid flow is determined by a fixed or variable angle swashplate movement direction and magnitude of hydraulic fluid flow into the Hydraulic fluid chamber region is controlled by an angle through which the swash plate is tilted.

[0120] Clause 32. The aircraft, in accordance with clause 28, in which the electro-hydrostatic actuator further comprises a separation element located within the hydraulic cylinder that separates the reservoir into a compressed gas chamber area and a hydraulic fluid chamber.

[0121] Clause 33. The aircraft in accordance with clause 28, in which the piston assembly is moved in a first direction from a retracted position to an extended position by pumping hydraulic fluid from at least one of the rod-side chamber and from the reservoir into the piston-side chamber and pushing fluid from the rod-side chamber into the reservoir, and where the piston assembly is moved in a second direction opposite to the first direction by pumping hydraulic fluid from at least one of a piston side chamber and the reservoir into the rod side chamber and pushing the fluid from the piston side chamber into the reservoir.

[0122] Clause 34. The aircraft in accordance with clause 28, in which the electric motor is a servo motor and the hydraulic pump system is a bidirectional positive displacement pump.

[0123] Clause 35. The aircraft according to clause 28, in which the electro-hydrostatic actuator further comprises a rotating valve plate within the hydraulic cylinder boss.

[0124] While the present description has been particularly illustrated and described with reference to specific examples thereof, it will be understood by those skilled in the art that changes in the form and details of the described examples can be made without departing from the spirit or scope of the present description. It is therefore intended that the present description be interpreted to include all variations and equivalences that are within the true spirit and scope of the present description. Although many of the components and processes are described above in the singular for reasons of convenience, it will be appreciated by those skilled in the art that multiple components and repeated processes may also be used to practice the techniques of the present disclosure.

Claims (15)

1. Electro-hydrostatic actuator (100), characterized by the fact that it comprises: a piston assembly (20) having a piston head (26) and a piston rod (22) extending from the piston head (26 ); a hydraulic cylinder (30, 210), in which the piston assembly (20) is located and is movable within the hydraulic cylinder (30, 210), the hydraulic cylinder (30, 210) including a hydraulic fluid chamber region ( 28) including a piston side chamber (32) and a rod side chamber (34); a reservoir (36, 360) for storing hydraulic fluid located within the electro-hydrostatic actuator (100) that is in fluid communication with the hydraulic fluid chamber region (28); wherein the reservoir (36, 360) is formed between an inner surface (364A) of a reservoir wall (364) and an outer surface (362A) of an outer periphery of the hydraulic cylinder housing (362), wherein the reservoir (36, 360) has its interior subdivided into a first (350A) and a second (350B) pressure compartments by an accordion assembly (351), the first pressure compartment (350A) includes a first gas pressure compartment located in toward the piston rod end (202), wherein the second pressure compartment (350B) is located toward the piston end and in fluid communication with the hydraulic fluid chamber region (28) and a control network flow system (38, 420), wherein the accordion assembly (351) is a thin-walled metallic or non-metallic concertina and includes an outer concertina (352) and an internal concertina (354), wherein the external concertina (352) is fitted to be surrounded by and abutted against the inner surface (364A) of the reservoir wall (36, 360), while the inner accordion (354) is fitted to surround and abutted against the outer surface (362A) of the hydraulic cylinder housing (362), the interior of the concertina assembly (351) being a pressure storage chamber (356) filled with a gas under high pressure; a hydraulic pump system (40) for moving hydraulic fluid in the reservoir (36, 360) and in the hydraulic fluid chamber region (28), the hydraulic pump system (40) in fluid communication with the hydraulic fluid control network flow (38, 420) in a hydraulic cylinder boss (211) to control a direction and magnitude of flow of hydraulic fluid within the hydraulic fluid chamber region (28); and an electric motor (50) located within the hydraulic cylinder (30, 210) to drive the hydraulic pump system (40). 2. Electro-hydrostatic actuator (100), according to claim 1, characterized by the fact that it further comprises an integrated control module (60) located within the electro-hydrostatic actuator (100) for receiving a control signal and converting the control signal into a set point value at which the electric motor (50) drives the hydraulic pump system (40). 3. Electro-hydrostatic actuator (100), according to claim 1, characterized by the fact that the electric motor (50) rotates a fixed or variable angle swashplate (42, 224, 408) to activate the system hydraulic pump (40), and wherein at least one of: the direction of hydraulic fluid flow is determined by a direction of movement of the fixed or variable angle swash plate (42, 224, 408) and the flow magnitude of the hydraulic fluid into the hydraulic fluid chamber region (28) and controlled by an angle through which the swash plate (42, 224, 408) is tilted, the electro-hydrostatic actuator (100) further including an integrated control module (60) located within the electro-hydrostatic actuator (100) to receive an electrical control signal that controls the direction of movement of the fixed or variable angle swashplate (42, 224, 408) and the tilt angle of the swashplate. fixed or variable angle (42, 224, 408); and wherein the hydraulic pump system (40) comprises a hydraulic pump cylinder block (214, 402) that is rotatable within the electro-hydrostatic actuator (100), the hydraulic pump cylinder block (214, 402) comprising a plurality of pistons (216, 406) which are movable by rotation of the fixed or variable angle swashplate (42, 224, 408), and wherein the plurality of pistons (216, 406) are coupled to the swashplate (42, 406) 224, 408) and slides within the hydraulic pump cylinder block (214, 402) along a direction of a central axis (X) of the electro-hydrostatic actuator (100). 4. Electro-hydrostatic actuator (100), according to claim 1, characterized by the fact that: the piston assembly (20) is moved in a first direction, from a retracted position to an extended position, by pumping hydraulic fluid from at least one of the rod-side chamber (34) and reservoir (36, 360) into the piston-side chamber (32) and pushing the fluid from the rod side chamber (34) into the reservoir (36, 360), and wherein the piston assembly (20) is moved in a second direction opposite to the first direction by pumping hydraulic fluid from at least one chamber side piston (32) and reservoir (36, 360) into the rod side chamber (34) and pushing hydraulic fluid from the piston side chamber (32) into the reservoir (36, 360 ). 5. Electro-hydrostatic actuator (100), according to claim 1, characterized by the fact that the hydraulic pump system includes a valve plate (44, 212, 404). 6. Electro-hydrostatic actuator (100), according to claim 5, characterized by the fact that a direction of flow of hydraulic fluid supplied by or returned to the hydraulic pump system (40) is controlled by the valve plate (44, 212, 404), and wherein at least one of: the valve plate (44, 212, 404) is mechanically attached to or integral with the hydraulic cylinder boss (211); and the valve plate (44, 212, 404) is rotatable within the hydraulic cylinder boss (211). 7. Electro-hydrostatic actuator (100), according to any one of claims 1 to 6, characterized by the fact that the electric motor (50) is a servomotor and the hydraulic pump system (40) is a positive displacement pump bidirectional, and wherein at least one of: a position of the piston assembly (20) within the hydraulic cylinder (30, 210) and an output force produced by the piston assembly (20) are controlled by modulation of one of: a an electric servomotor speed, a positive displacement pump speed, or a combination thereof, wherein a position of the piston assembly (20) and output force are controlled by changing a servomotor speed and direction; and the flow control network (38, 420) is integrated into the hydraulic cylinder boss (211). 8. Electro-hydrostatic actuator (100), according to any one of claims 1 to 7, characterized in that it further comprises a thermal management system (70), wherein the thermal management system (70) is arranged to surround the thermal hot spots on an outer periphery of the driver (100). 9. Electro-hydrostatic actuator (100), according to claim 1, characterized by the fact that it further comprises a position sensor (62) that monitors a position of the actuator (100), wherein at least one of a speed and direction of the electric motor (50) is controlled according to the position of the driver (100). 10. Aircraft (600) characterized by the fact that it comprises an electro-hydrostatic actuator (100) as defined in claim 1. 11. Aircraft according to claim 10, characterized by the fact that the electro-hydrostatic actuator (100) further comprises at least one of: an integrated control module (60) located within the electro-hydrostatic actuator (100) for receiving a control signal and converting the control signal into a set point value at which the electric motor (50) drives the hydraulic pump system (40); and a valve plate (44, 212, 404) rotatable within the hydraulic cylinder boss (211). 12. Aircraft according to claim 10 or 11, characterized by the fact that the electric motor performs at least one of: rotating a fixed or variable angle swashplate (42, 224, 408) to drive the hydraulic pump (40); and a servomotor and hydraulic pump system (40) is a bidirectional positive displacement pump. 13. Aircraft according to claim 12, characterized by the fact that the direction of hydraulic fluid flow is determined by a fixed or variable angle swash plate movement direction (42, 224, 408) and the flow magnitude of hydraulic fluid into the hydraulic fluid chamber region (28) is controlled by an angle through which the swash plate (42, 224, 408) is tilted. 14. Aircraft according to any one of claims 10 to 13, characterized by the fact that: the piston assembly (20) is moved in a first direction from a retracted position to an extended position by pumping fluid hydraulic from at least one of the rod-side chamber (34) and from the reservoir (36, 360) into the piston-side chamber (32) and pushing fluid from the rod-side chamber (34 ) into the reservoir (36, 360); and wherein the piston assembly (20) is moved in a second direction, opposite to the first direction, by pumping hydraulic fluid from at least one of a piston side chamber (32) and the reservoir (36, 360 ) into the rod-side chamber (34) and pushing fluid from the piston-side chamber (32) into the reservoir (36, 360). 15. Integrated accumulator and piping system (210, 206, 204) of a hydrostatic actuator (100) characterized by the fact that it comprises: an inner surface (334, 362A) surrounding an outer periphery (362) of a housing (30- A) of a hydraulic cylinder (30, 210), the hydraulic cylinder (30, 210) including a piston assembly (20, 208) having a piston head (26) and a piston rod (22) extending from of the piston head (26), the housing (30-A) including a hydraulic fluid chamber region (28) including a piston side chamber (32) and a rod side chamber (34); an outer surface (332, 364A) defining a reservoir (36, 360) between the inner surface (334, 362A) and the outer surface (332, 364A), wherein the reservoir (36, 360) is in fluid communication with the hydraulic fluid chamber region (28), wherein the reservoir (36, 360) is configured to surround an outer periphery (362) of the hydraulic fluid chamber region (28) and is subdivided into a first (350A) and a second pressure chamber (350B) by an accordion assembly (351), the first pressure chamber (350A) includes a first gas pressure chamber, the second pressure chamber (350B) includes a fluid pressure chamber, the concertina assembly (351) includes a third pressure chamber different from the first (350A) and second (350B) pressure chambers, the third pressure chamber includes a second gas pressure chamber separate from the first gas pressure chamber; and a fluid flow control network (38, 420) in fluid communication with a hydraulic pump system (40) of the driver (100) to control a direction and magnitude of flow of hydraulic fluid within the chamber region. of hydraulic fluid (28), wherein the hydraulic pump system moves hydraulic fluid in the reservoir (36, 360) and hydraulic fluid chamber region (28), the flow control network (38, 420) includes a first fluid passage (551) and a second fluid passage (553) separated by a check valve and an anti-cavitation valve (552), the check valve and the anti-cavitation valve (552) configured to restrict uncontrolled fluid flow between the first fluid passage (551) and the second fluid passage (553), the anti-cavitation valve (552) is further configured to reduce damage caused by cavitation to the hydraulic pump system (40).