Non-similar energy medium multi-stage electrotransmission machine electric actuator

Abstract

The non-similar energy medium multi-stage electric transmission machine electric actuator is safe and reliable, has large load stiffness and high transmission efficiency.The application is realized through the following technical scheme: the main lead screw nut driven by the main lead screw cylinder with an anti-jamming mechanism drives the first-stage piston cylinder to make extension and retraction movement in the outer cylinder movement cavity;the bearing sleeve assembled through the end wall cavity limits the secondary lead screw cylinder in the end ring groove of the secondary lead screw cylinder;the secondary lead screw cylinder is coupled through the end ring groove and the secondary lead screw nut constrained by the inner cavity of the second-stage piston cylinder piston head;the secondary lead screw cylinder is sleeved with the secondary lead screw nut, drives the second-stage piston cylinder to make extension and retraction movement in the first-stage piston cylinder movement cavity, and forms the main channel piston cylinder extension and retraction movement channel of the main and secondary double-thread lead screw nut combination;the spline sleeve transmission shaft drives the secondary lead screw cylinder to rotate, drives the secondary lead screw nut and the sleeved second-stage piston cylinder to make extension and retraction movement in the first-stage piston cylinder end movement cavity, and thus forms the multi-stage electric transmission machine electric actuator of the non-similar energy medium emergency extension piston cylinder action.

Description

Technical Field

[0001] This invention relates to an emergency actuation structure applied to multi-stage electromechanical actuators; more specifically, this invention relates to an innovative structure that can improve the safety and mission reliability of electromechanical actuators and realize the extension of multi-stage piston cylinders in multi-media emergency situations. Background Technology

[0002] Electromechanical actuation systems (EMAs) require multiple (usually three or more) EMAs to drive aircraft control surfaces, landing gear retraction and extension, and cabin door retraction and extension. An EMA, as a linear motion actuator, is an energy conversion device used to achieve linear reciprocating motion or oscillating motion less than 360° in a working mechanism. The basic components of a common EMA are as follows: motor, gearbox, transmission components, ball screw assembly, outer cylinder assembly, piston cylinder assembly, etc. The advantages of EMAs are high reliability, simple structure, and high transmission efficiency. However, because EMAs cannot perform fault follow-up after jamming, it is necessary to prevent damage to the actuator and structure caused by jamming. Currently, EMAs have slow dynamic response speed, low load stiffness, and persistent static error. Furthermore, high-power mechanical transmission mechanisms are bulky and heavy, resulting in excessive rotational inertia for the entire fly-by-wire system, making the implementation of EMAs in high-power airborne transmission systems difficult. Therefore, currently, EMAs are only implemented in fly-by-wire systems on aircraft with low power requirements. To address the aforementioned issues, electro-hydraulic actuators (SHAs) are often employed, characterized by high efficiency and low heat generation. These SHAs typically consist of an actuator controller, a DC brushless servo motor, a bidirectional hydraulic pump, a hydraulic actuator cylinder, an accumulator serving as a fuel tank, a power driver, and signal processing units. The servo controller receives command signals from the computer, drives the motor via the motor controller, and then drives the bidirectional hydraulic pump, causing the actuator cylinder to move according to the command. The main system comprises electro-hydraulic servo valves, hydraulic cylinders, and function valves, with the hydraulic oil sourced from a central hydraulic power source. A unidirectional fixed displacement pump is driven by a motor, and an overflow valve maintains a constant pressure in the system. When the actuator is not moving, excess flow is discharged through the overflow valve, converting entirely into heat. If heat dissipation is inadequate, the actuator temperature rises rapidly. Therefore, this type of electro-hydraulic actuator cannot operate for extended periods (typically a few minutes to tens of minutes), failing to meet the requirements for long-term aircraft operation. To address these problems, existing technologies have proposed dissimilar redundant power fly-by-wire actuation systems. A non-dissimilar redundant power-to-electric actuator system refers to a redundant actuator system composed of two actuators using different working principles and structural components to complete the same task. The advantage of this system is that the product can continue to operate even when a common-mode failure occurs in the actuator system. The non-dissimilar redundant power-to-electric actuator system uses a combined actuator as the main channel and an electro-hydraulic actuator as the backup channel. This scheme employs a main-backup redundancy monitoring system. When the main actuator is running, the backup actuator is in a hot reserve state; when the main actuator fails, through fault monitoring, detection, and fault switching, the backup actuator is immediately connected to the system to replace the main actuator. Although this scheme has a mature technical foundation and acceptable performance indicators, the coexistence of multiple energy sources leads to problems such as a bulky internal structure, complex accessories, limited installation space, inconvenient maintenance, and easy leakage of hydraulic and pneumatic energy, resulting in a high failure rate and poor reliability.To improve the reliability of servo actuator systems, existing technologies have proposed dissimilar redundancy design schemes. Dissimilar redundancy actuator systems have two or more channels that are not completely identical in hardware or software operating synchronously. For example, the processor, controller software, and electromechanical components of a servo controller can all adopt dissimilar redundancy design. Parallel redundancy actuators suffer from signal mismatch issues, thus requiring balancing methods. Common methods include mechanical force integration, hydraulic pressure integration, and flux integration. Mechanical force integration actuators suffer from force contention; electromechanical actuators using force integration can lead to asynchrony. Balancing techniques or decoupling control are needed to mitigate or eliminate force contention. Hydraulic pressure integration adds the output forces of the two actuator cylinders as the output, eliminating force contention issues, and is therefore frequently used in similar redundancy actuators. However, because the dynamic response of electro-hydraulic actuator systems is slower than that of electro-hydraulic servo actuators, if hydraulic pressure integration is used, the output force difference acting on the piston cylinder of the actuator cylinder can be significant in a short period of time. Furthermore, centralized energy hydraulic actuation systems suffer from disadvantages such as large weight, low efficiency, and high maintenance costs, as well as safety issues such as fluid leakage. If dissimilar hybrid actuators are used in multi-electric aircraft, the hybrid redundancy actuation system faces force conflict issues due to the dissimilar redundancy configuration.

[0003] While airborne fly-by-wire actuators are relatively easy to install and remove and maintain, they place high demands on their reliability. For fly-by-wire control system actuators, a failure rate of less than 10% is required. -4 The range. According to reliability analysis, the failure rate of a single-redundant power actuator is 10%. -8 ~10 -9 The scale is so large that a single system cannot meet the reliability requirements of airborne fly-by-wire actuation systems. In some applications with limited installation space or long working stroke requirements, such as aircraft landing gear retraction and extension, and door retraction and extension, single-stage electromechanical actuators are often used but cannot meet the limited installation space requirements due to their long overall dead structure length, thus resulting in poor practicality. Although multi-stage electromechanical actuators can be used to effectively shorten the dead structure length, conventional multi-stage electromechanical actuators still face the problem of single-point failures such as lead screw and cylinder pair jamming. If it cannot be guaranteed that multi-stage electromechanical actuators can still isolate faults and achieve emergency operation in emergency situations, the application range of multi-stage electromechanical actuators will be greatly limited. Summary of the Invention

[0004] This invention provides a solution for an emergency extension piston cylinder that is simple in structure, safe and reliable, has high load stiffness, high transmission efficiency, can achieve small installation space and large working stroke, can ensure aircraft flight safety, and does not rely on electricity. It can effectively solve the single-point failure problem of screw cylinder pair jamming in conventional multi-stage electromechanical actuators and realize the redundant emergency extension function for different working media.

[0005] The technical solution adopted by this invention to solve its technical problem is: a multi-stage electromechanical actuator for dissimilar energy media, comprising: a main motor 1 and an auxiliary motor 16, which are respectively shafted on both radial sides of an outer cylinder 3 via a gear transmission system and a nut-rotating lead screw and a splined sleeve transmission shaft 18; and a piston cylinder that performs linear telescopic motion in the moving cavity of the outer cylinder 3 via the lead screw nut. The main motor 1's output gear meshes with the main lead screw 4 via a main transmission gear 2, driving the main lead screw 4 to rotate, which in turn drives the main lead screw nut 5 with an anti-jamming mechanism, thereby driving the first-stage piston cylinder 9 to perform telescopic motion in the moving cavity of the outer cylinder 3 with a pressure medium emergency nozzle 13. Simultaneously, the main lead screw nut 5, through a bearing sleeve 10 assembled in the hollow stepped cavity of the end wall, axially limits the auxiliary lead screw 14 in the end ring groove of the auxiliary lead screw 14, bearing the load of the auxiliary lead screw 14. The load of 14, the auxiliary lead screw cylinder 14 is coupled to the auxiliary lead screw cylinder nut 11 constrained by the stepped hole in the inner cavity of the piston head of the secondary piston cylinder 12 through the right stop ring end face of the end ring groove. The auxiliary lead screw cylinder nut 11 fits the outer helical raceway of the auxiliary lead screw cylinder 14, driving the secondary piston cylinder 12 to perform telescopic movement in the motion cavity of the primary piston cylinder 9, forming the main channel piston cylinder telescopic movement channel of the main and auxiliary double lead screw nut pair combination; the auxiliary motor 16 drives the spline sleeve drive shaft 18 to rotate through the auxiliary transmission gear 17. The spline sleeve drive shaft 18 drives the auxiliary lead screw cylinder 14 to rotate through the key smooth groove in the inner core of the auxiliary lead screw cylinder 14, thereby driving the auxiliary lead screw cylinder nut 11 and the fitted secondary piston cylinder 12 to perform telescopic movement in the motion cavity at the end of the primary piston cylinder 9, thus forming a multi-stage electromechanical actuator for emergency extension of piston cylinder action of dissimilar energy medium.

[0006] Compared with the prior art, the present invention has the following advantages:

[0007] This invention employs a dual-channel transmission device with a nut-rotating lead screw and a splined sleeve transmission shaft 18, respectively, driven by gear transmission systems on both radial sides of the outer cylinder 3. The piston cylinder, moving linearly within the outer cylinder 3's moving cavity, is driven by the lead screw and nut. This device has fewer components, a simpler structure, and higher transmission efficiency. Compared to traditional hydraulic actuators, it offers stronger load-bearing capacity, better motion accuracy, and higher transmission efficiency. This device uses balancing technology or decoupling control to alleviate or eliminate force conflicts, thus eliminating such problems. The main lead screw nut 5, through a bearing sleeve 10 mounted in the hollow stepped cavity of the end wall, axially limits the auxiliary lead screw cylinder 14 within its end ring groove, bearing the load of the auxiliary lead screw cylinder 14 and transmitting power in the form of electrical energy. This effectively converts the motor's motion into the lead screw's motion, potentially replacing or reducing the application of centralized hydraulic systems. By using two independent motors, the probability of common-mode failure is greatly reduced, overcoming the disadvantages of traditional integrated actuators, such as large size and weight and difficult control. At the same time, it avoids the occurrence of common-mode failures to a certain extent and improves the reliability of the actuator.

[0008] This invention employs a main motor 1 whose output gear meshes with a main drive gear 2 to rotate a main lead screw cylinder 4, thereby driving a main lead screw nut 5 with an anti-jamming mechanism. This drives a first-stage piston cylinder 9 to extend and retract within the moving chamber of an outer cylinder 3 containing a pressure medium emergency nozzle 13. A secondary motor 16 drives a splined sleeve drive shaft 18 to rotate via a secondary drive gear 17. The splined sleeve drive shaft 18 engages with a secondary lead screw cylinder 14 and a secondary lead screw nut 11, driving a second-stage piston cylinder 12 to extend and retract within the moving chamber of the first-stage piston cylinder 9. This design features high load stiffness, high rotational efficiency, and avoids complex force conflicts and coupling / decoupling issues, making it relatively easy to implement in engineering.

[0009] This invention incorporates an anti-jamming mechanism that can be unlocked by a high-pressure medium between the main lead screw nut 5, the first-stage piston cylinder 9, and the bearing sleeve 10. In the event of jamming in the lead screw and cylinder assembly or other transmission mechanisms, the high-pressure medium unlocks the anti-jamming mechanism, driving the first-stage piston cylinder 9 and the second-stage piston cylinder 12 to extend under load. Even when a common-mode failure occurs in the actuator system, the product can continue to operate, improving system reliability. This solves the single-point problem of conventional multi-stage electromechanical actuators being unable to extend the piston cylinder due to lead screw and cylinder assembly jamming.

[0010] This invention employs a secondary lead screw cylinder 14 coupled to a secondary lead screw cylinder nut 11 constrained by a stepped hole in the piston head cavity of a secondary piston cylinder 12 via the right stop ring end face of the end ring groove. The secondary lead screw cylinder nut 11 engages with the outer helical raceway of the secondary lead screw cylinder 14, driving the secondary piston cylinder 12 to perform telescopic motion within the motion chamber of the primary piston cylinder 9. This forms the main channel piston cylinder telescopic motion channel of the main and secondary double lead screw nut assembly. The two channels can work in coordination, forming a reliable hot backup. In the event of a fault, the fault can be quickly isolated, ensuring the safe and reliable operation of the system. Synchronization between the two channels enables the redundant system to operate reliably, improving dynamic performance compared to single-channel operation. Even if one channel fails, it can still operate normally, further enhancing the safety and reliability of the aircraft. By applying power-driven fly-by-wire actuation technology, it not only improves actuation efficiency, reduces aircraft weight, and controls maintenance costs, but also enhances dynamic performance compared to single-channel operation. Attached Figure Description

[0011] Figure 1 This is a cross-sectional view of the piston cylinder retracted state of the multi-stage electromechanical actuator with dissimilar energy media according to the present invention.

[0012] Figure 2 yes Figure 1 Left view of a partial cross-section of the drive shaft in spline engagement with the auxiliary lead screw;

[0013] Figure 3 A cross-sectional view of the piston cylinder extension state of a multi-stage electromechanical actuator with dissimilar energy media;

[0014] In the diagram: 1. Main motor; 2. Main drive gear; 3. Outer cylinder; 4. Main lead screw cylinder; 5. Main lead screw nut; 6. Locking spring; 7. Upper locking bushing; 8. Bearing sleeve locking steel ball; 9. First-stage piston cylinder; 10. Bearing sleeve; 11. Secondary lead screw cylinder nut; 12. Secondary piston cylinder; 13. Pressure medium emergency nozzle; 14. Secondary lead screw cylinder; 15. Main nut locking steel ball; 16. Secondary motor; 17. Secondary drive gear; 18. Splined sleeve drive shaft.

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this does not limit the invention to the scope of the described embodiments. All these concepts should be considered as the content disclosed in this technology and the scope of protection of this invention. Detailed Implementation

[0016] See Figures 1-3In the preferred embodiment described below, a multi-stage electromechanical actuator for dissimilar energy media includes: a main motor 1 and an auxiliary motor 16, which are respectively shafted on both radial sides of an outer cylinder 3 via a gear transmission system to a nut-rotating lead screw and a splined sleeve transmission shaft 18; a piston cylinder that performs linear telescopic motion within the moving cavity of the outer cylinder 3 via the lead screw nut; wherein: the output gear of the main motor 1 meshes with the main lead screw 4 via a main transmission gear 2, causing the main lead screw 4 to rotate, driving the main lead screw nut 5 with an anti-jamming mechanism, and causing the first-stage piston cylinder 9 to perform telescopic motion within the moving cavity of the outer cylinder 3 with a pressure medium emergency nozzle 13; simultaneously, the main lead screw nut 5, through a bearing sleeve 10 assembled in the hollow stepped cavity of the end wall, axially limits the auxiliary lead screw 14 in the end ring groove of the auxiliary lead screw 14, bearing the load of the auxiliary lead screw 14. The auxiliary lead screw cylinder 14 is coupled to the auxiliary lead screw cylinder nut 11, which is constrained by the stepped hole in the inner cavity of the piston head of the secondary piston cylinder 12, through the right stop ring end face of the end ring groove. The auxiliary lead screw cylinder nut 11 fits into the outer helical raceway of the auxiliary lead screw cylinder 14, driving the secondary piston cylinder 12 to perform telescopic movement in the motion cavity of the primary piston cylinder 9, thus forming the main channel piston cylinder telescopic movement channel of the main and auxiliary double lead screw nut pair combination; the auxiliary motor 16 drives the spline sleeve drive shaft 18 to rotate through the auxiliary transmission gear 17, and the spline sleeve drive shaft 18 drives the auxiliary lead screw cylinder 14 to rotate through the key smooth groove in the inner cavity of the auxiliary lead screw cylinder 14, thereby driving the auxiliary lead screw cylinder nut 11 and the fitted secondary piston cylinder 12 to perform telescopic movement in the motion cavity at the end of the primary piston cylinder 9, thus forming a multi-stage electromechanical actuator for emergency extension of piston cylinder action of dissimilar energy medium.

[0017] The anti-jamming mechanism includes: a locking bushing 7 sealed in the inner annular hole of the small end of the main screw nut 5; a flanged sleeve end cap sealed through the center hole of the locking bushing 7; a locking spring 6 fitted on the outer annular surface of the flanged sleeve end cap; a bearing sleeve 10 constrained by the left stepped end face and tightly attached to the stepped end face of the inner annular hole of the piston head at the bottom of the first-stage piston cylinder 9, and constrained by the bidirectional thrust angular contact ball bearing in the end ring cylindrical bearing receiving cavity; a bearing sleeve locking steel ball 8 locked in the steel ball guide lock hole on the outer annular surface; and a main nut locking steel ball 15 locked in the steel ball guide lock hole on the outer annular surface of the main screw nut 5.

[0018] The piston head of the first-stage piston cylinder 9 engages with the outer ring surface of the small end step of the main screw nut 5. When the piston cylinder is retracted, the main nut locking steel ball 15 and the bearing sleeve locking steel ball 8, which are locked in the locking groove along the inner ring hole wall, are locked in the steel ball guide locking hole. The outer ring surface of the upper locking bushing 7 is close to the lower edge of the main nut locking steel ball 15 and the bearing sleeve locking ball 8, and the locking spring 6 is held in the step cavity inside the blind hole by its elasticity, limiting the movement of the main nut locking steel ball 15 and the bearing sleeve locking ball 8, thereby realizing the anti-jamming locking of the main screw nut 5, the first-stage piston cylinder 9, and the bearing sleeve 10.

[0019] The output tooth diameter of the main motor 1 extends radially into the transmission cavity of the outer cylinder 3 through the main transmission gear 2, and meshes with the end gear of the main screw cylinder 4. This drives the thrust angular contact ball bearing assembled through the stepped annular hole at the bottom of the outer cylinder 3 and the main screw nut 5, which is mounted on the outer helical raceway of the main screw cylinder 4, to perform telescopic movements. The main screw nut 5 pushes the main nut locking steel ball 15, which is locked in the steel ball guide lock hole 8 through the small end step, and drives the first-stage piston cylinder 9 to perform telescopic movements in the motion cavity of the outer cylinder 3.

[0020] The output gear of the secondary drive motor 16 extends radially into the transmission cavity of the outer cylinder 3 through the auxiliary transmission gear 17 and meshes with the end gear of the spline sleeve transmission shaft 18. The spline sleeve transmission shaft 18 engages with the auxiliary lead screw cylinder 14 through the external spline teeth, and moves linearly towards the motion cavity at the end of the auxiliary lead screw cylinder 14, thereby driving the auxiliary lead screw cylinder 14 to rotate.

[0021] The axial limiting auxiliary lead screw cylinder 14 of the bidirectional thrust angular contact ball bearing end face is assembled in the hollow stepped hole of the bearing sleeve 10, which restricts the axial displacement of the auxiliary lead screw cylinder 14 in both directions and bears the load of the auxiliary lead screw cylinder 14.

[0022] The main screw nut 5 is coaxially connected to the bearing sleeve 10, locking the anti-jamming mechanism together with the first-stage piston cylinder 9.

[0023] The main screw nut 5 is coupled to the secondary screw cylinder 14 through the bearing sleeve 10. The outer spiral race of the secondary screw cylinder nut 11 is fitted to the secondary screw cylinder 14, and the load is sequentially transmitted to the secondary screw cylinder 14. Driven by the secondary screw cylinder 14, the secondary piston cylinder 12 is driven to perform telescopic movement in the moving cavity of the primary piston cylinder 9.

[0024] When the piston cylinder is retracted, the auxiliary lead screw nut 11, which is constrained in the hollow stepped hole of the secondary piston cylinder 12, transmits the load sequentially to the auxiliary lead screw cylinder 14, the primary piston cylinder 9, the main lead screw nut 5, the main lead screw cylinder 4, and finally to the outer cylinder 3.

[0025] During normal operation, the main motor 1 drives the main lead screw cylinder 4 to rotate, which in turn drives the main lead screw nut 5 and the auxiliary lead screw cylinder 14 to extend. At the same time, it drives the first-stage piston cylinder 9 to extend out of the outer cylinder 3's moving cavity. Simultaneously, the second-stage drive motor 16 extends radially into the outer cylinder 3's transmission cavity through the auxiliary transmission gear 17, driving the gear at the end of the spline sleeve transmission shaft 18 to rotate. The spline sleeve transmission shaft 18 engages with the inner ring spline groove of the auxiliary lead screw cylinder 14 through the spline of the free end cylindrical platform, driving the auxiliary lead screw cylinder 14 to rotate synchronously. This drives the second-stage piston cylinder 12, which is fitted with the auxiliary lead screw cylinder nut 11, to extend out of the first-stage piston cylinder 9. The total working stroke of the actuator is the sum of the stroke from the piston head step end face of the second-stage piston cylinder 12 to the bottom end of the first-stage piston cylinder 9's moving cavity and the stroke from the piston head step end face of the first-stage piston cylinder 9 to the bottom end of the outer cylinder 3's moving cavity.

[0026] In an alternative embodiment, if the motor fails or any transmission mechanism jams, a high-pressure medium, which is a dissimilar energy source to electrical energy, enters the inner cavity of the actuator's outer cylinder 3 from the pressure medium emergency nozzle 13 of the outer cylinder 3. The high-pressure medium pushes the locking bushing 7 of the anti-jamming mechanism ring seal to move to the left against the elastic force of the locking spring 6. The main nut locking steel ball 15 and the bearing sleeve locking steel ball 8 disengage from the locking groove of the first-stage piston cylinder 9 and fall into the chamfered surface at the end of the locking bushing 7, thereby unlocking the anti-jamming mechanism. That is, the first-stage piston cylinder 9, the main screw nut 5, and the bearing sleeve 10 disengage from each other, and the second-stage piston cylinder 12 extends out of the first-stage piston cylinder 9 against the load, completing the emergency extension piston cylinder action.

[0027] Although the present invention has been described in conjunction with some preferred embodiments, the invention is not limited to these embodiments. Rather, the invention is intended to encompass all alternatives, modifications, and equivalents, provided that such alternatives are included within the core spirit and scope of the invention as defined by the appended claims.

Claims

1. A multi-stage electromechanical actuator using dissimilar energy media, comprising: The outer cylinder (3) has a main motor (1) and an auxiliary motor (16) arranged on its radial sides. The outer cylinder (3) has a piston cylinder capable of linear telescopic movement in its moving cavity. The main motor (1) output gear meshes with the main screw cylinder (4) through the main transmission gear (2) to drive the main screw cylinder (4) to rotate, thereby driving the main screw nut (5) with an anti-jamming mechanism to drive the first-stage piston cylinder (9) to telescopically move in the moving cavity of the outer cylinder (3) with a pressure medium emergency nozzle (13). At the same time, the main screw nut (5) passes through the end wall. The bearing sleeve (10) assembled in the hollow stepped cavity axially limits the auxiliary lead screw cylinder (14) in the end ring groove of the auxiliary lead screw cylinder (14) and bears the load of the auxiliary lead screw cylinder (14). The auxiliary lead screw cylinder (14) is coupled to the auxiliary lead screw cylinder nut (11) constrained by the stepped hole in the inner cavity of the piston head of the secondary piston cylinder (12) through the right stop ring end face of the end ring groove. The nut (11) fits the outer helical raceway of the auxiliary lead screw cylinder (14) and drives the secondary piston cylinder (12) to perform telescopic movement in the motion cavity of the primary piston cylinder (9). This constitutes the main channel piston cylinder telescopic movement channel of the main and auxiliary double lead screw nut assembly. The auxiliary motor (16) drives the spline sleeve drive shaft (18) to rotate through the auxiliary transmission gear (17). The spline sleeve drive shaft (18) drives the auxiliary lead screw cylinder (14) to rotate through the keyway groove inside the auxiliary lead screw cylinder (14), thereby driving the auxiliary lead screw cylinder nut (11) and the fitted secondary piston cylinder (12) to extend and retract into the motion chamber at the end of the primary piston cylinder (9), thus forming a multi-stage electromechanical actuator for emergency extension of the piston cylinder in dissimilar energy media. The anti-jamming mechanism includes: a locking bushing sealed in the inner annular hole of the small end of the main lead screw nut (5). (7) The flanged sleeve end cap sealed by the center hole ring of the upper locking bushing (7) is fitted with the locking spring (6) on the outer ring surface of the flanged sleeve end cap. The left step end face constrains the piston head inner ring hole step end face of the first-stage piston cylinder (9) and constrains the bidirectional thrust angular contact ball bearing in the bearing sleeve (10) in the end ring cylindrical bearing cavity. The outer ring circumference of the bearing sleeve locks the steel ball (8) in the steel ball guide lock hole. The main nut locks the steel ball (15) in the steel ball guide lock hole on the outer ring circumference of the main screw nut (5).

2. The multi-stage electromechanical actuator with dissimilar energy media as described in claim 1, characterized in that: The piston head of the first-stage piston cylinder (9) is fitted with the outer ring surface of the small end step of the main screw nut (5). When the piston cylinder is retracted, the main nut locking steel ball (15) and the bearing sleeve locking steel ball (8) locked in the locking groove along the inner ring hole wall are locked in the steel ball guide lock hole. The outer ring surface of the upper locking bushing (7) is close to the lower edge of the main nut locking steel ball (15) and the bearing sleeve locking steel ball (8). The spring force of the locking spring (6) is kept in the step cavity inside the blind hole, limiting the movement of the main nut locking steel ball (15) and the bearing sleeve locking steel ball (8), so as to realize the anti-jamming locking of the main screw nut (5), the first-stage piston cylinder (9), and the bearing sleeve (10).

3. The multi-stage electromechanical actuator with dissimilar energy media as described in claim 1, characterized in that: The output tooth diameter of the main motor (1) extends radially into the transmission cavity of the outer cylinder (3) through the main transmission gear (2), meshes with the end gear of the main screw cylinder (4), and drives the thrust angular contact ball bearing assembled through the step ring hole of the bottom cavity of the outer cylinder (3) and the main screw nut (5) mounted on the outer spiral raceway of the main screw cylinder (4) to perform telescopic movement. The main screw nut (5) pushes the main nut locking steel ball (15) locked in the steel ball guide lock hole through the small end step, and drives the first-stage piston cylinder (9) to perform telescopic movement in the motion cavity of the outer cylinder (3).

4. The multi-stage electromechanical actuator with dissimilar energy media as described in claim 1, characterized in that: The output gear of the auxiliary motor (16) extends radially into the transmission cavity of the outer cylinder (3) through the auxiliary transmission gear (17) and meshes with the end gear of the spline sleeve transmission shaft (18). The spline sleeve transmission shaft (18) engages with the auxiliary lead screw cylinder (14) through the external spline teeth, and moves linearly towards the motion cavity at the end of the auxiliary lead screw cylinder (14), thereby driving the auxiliary lead screw cylinder (14) to rotate.

5. The multi-stage electromechanical actuator with dissimilar energy media as described in claim 1, characterized in that: The axial limiting auxiliary screw cylinder (14) of the two-way thrust angular contact ball bearing end face is assembled in the hollow stepped hole of the bearing sleeve (10), which restricts the axial displacement of the auxiliary screw cylinder (14) in both directions and bears the load of the auxiliary screw cylinder (14).

6. The multi-stage electromechanical actuator with dissimilar energy media as described in claim 1, characterized in that: The main screw nut (5) is coaxially connected to the bearing sleeve (10), locking the anti-jamming mechanism together with the first-stage piston cylinder (9).

7. The multi-stage electromechanical actuator with dissimilar energy media as described in claim 1, characterized in that: The main screw nut (5) is coupled to the auxiliary screw cylinder (14) through the bearing sleeve (10). The auxiliary screw cylinder nut (11) is fitted with the auxiliary screw cylinder (14) by the outer helical raceway, and the load is sequentially transmitted to the auxiliary screw cylinder (14). Driven by the auxiliary screw cylinder (14), the secondary piston cylinder (12) moves in the moving cavity of the primary piston cylinder (9) in a telescopic motion.

8. The multi-stage electromechanical actuator with dissimilar energy media as described in claim 1, characterized in that: When the piston cylinder is retracted, the auxiliary lead screw nut (11) constrained in the hollow stepped hole of the secondary piston cylinder (12) transmits the load sequentially to the auxiliary lead screw cylinder (14), the primary piston cylinder (9), the main lead screw nut (5), the main lead screw cylinder (4), and finally to the outer cylinder (3).

9. The multi-stage electromechanical actuator with dissimilar energy media as described in claim 1, characterized in that: During normal operation, the main motor (1) drives the main lead screw cylinder (4) to rotate, which in turn drives the main lead screw nut (5) and the auxiliary lead screw cylinder (14) to extend. At the same time, the first-stage piston cylinder (9) extends out of the outer cylinder (3) motion chamber. Meanwhile, the auxiliary motor (16) extends radially into the outer cylinder (3) transmission chamber through the auxiliary transmission gear (17), driving the gear at the end of the spline sleeve transmission shaft (18) to rotate. The spline sleeve transmission shaft (18) meshes with the inner ring spline groove of the auxiliary lead screw cylinder (14) through the spline of the free end cylindrical platform, driving the auxiliary lead screw cylinder (14) to rotate synchronously, driving the second-stage piston cylinder (12) fitted by the auxiliary lead screw cylinder nut (11) to extend out of the first-stage piston cylinder (9). The total working stroke of the actuator is the sum of the working stroke from the piston head step end face of the second-stage piston cylinder (12) to the bottom end of the motion chamber of the first-stage piston cylinder (9) and the working stroke from the piston head step end face of the first-stage piston cylinder (9) to the bottom end of the motion chamber of the outer cylinder (3).

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