Double ended lock carrying extension and retraction electro-mechanical actuator

Abstract

The double-end lock bearing release and take-up electromechanical actuator is simple, reliable and high in transmission efficiency. The anti-jamming lock in the hollow cavity of the piston head is statically connected through the screw nut, the emergency extension is in the high-pressure medium gas into the outer cylinder high-pressure cavity, the anti-jamming lock bushing is driven to move right through the screw nut ring gap channel, the lock jaw ring buckle on the ring cylinder lock buckle is pushed out of the buckle lock groove, the upper lock block is slid out of the lock groove conical slope, the step follow-up sleeve is driven, the piston cylinder is pushed to overcome the load to extend, the piston cylinder extends to the limit position, the lower lock block is slid along the outer cylinder and clamped into the lower lock groove at the cavity end, and the piston cylinder cannot be moved and is locked. The anti-jamming lock together with the piston cylinder emergency release and locking and the outer cylinder cavity end ring seal hole constitute the double-end lock bearing anti-jamming lock mechanism. The electromechanical actuator release and locking capacity and task reliability are improved.

Description

Technical Field

[0001] This invention relates to a functional structure for integrating heavy-load retraction, heavy-load locking, and emergency dissimilar energy into an electromechanical actuator. More specifically, this invention relates to an innovative structure that can improve the retraction capability, locking capability, actuator safety, and task reliability of an electromechanical actuator. In the case of actuator screw assembly jamming, dissimilar energy can isolate the jammed screw assembly from the piston cylinder, unlock the actuator's upper lock, and push the piston cylinder to extend over the load. Background Technology

[0002] Electromechanical actuators, as linear motion execution elements, are energy conversion devices used to achieve linear reciprocating motion or oscillating motion less than 360° in working mechanisms. The basic components of a common electromechanical actuator are as follows: motor, gearbox, transmission components, ball screw pair, outer cylinder assembly, piston cylinder assembly, and self-locking assembly. Electromechanical actuators with self-locking devices prevent lateral movement caused by external forces when stopped at a defined position; this is usually achieved by a mechanical lock within the actuator cylinder. The most common type of mechanical lock is a ball lock, which consists of a steel ball, a locking groove, a conical piston, and a spring. In applications with high safety and reliability requirements, such as electromechanical actuators used in aircraft landing gear retraction and extension, a safety margin must be provided for lowering the landing gear. The aerodynamic loads experienced by the landing gear during retraction and extension are quite complex. Electro-backup mechanical actuators (EBMAs): Normally driven by the aircraft's hydraulic power source, the EBMA provides emergency power to the landing gear in case of hydraulic power failure or other malfunctions. This actuator integrates hydraulic and electro-backup mechanical actuation functions. An electric motor and reduction gear are added to the end cap of the hydraulic actuator cylinder, and a roller screw mechanism is integrated inside the hydraulic piston cylinder. During normal operation, it is hydraulically driven; in emergencies, the electric mechanism drives the roller screw to extend the piston cylinder, thus enabling the emergency deployment of the main landing gear door. This actuator has a relatively complex structure and is difficult to manufacture. Furthermore, the problem of jamming in the electric mechanism and roller screw needs to be solved; otherwise, jamming will directly prevent the landing gear or door from being deployed. Commonly used EBMAs have a redundancy design with a backup motor. When the main motor fails, the backup motor operates to deploy the piston cylinder in an emergency. However, this cannot solve the single-point failure of the screw pair jamming, resulting in low reliability and poor practicality. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a solution that is simple in structure, safe and reliable, with high transmission efficiency, capable of heavy-load retraction and locking, and emergency unlocking and piston cylinder extension under dissimilar energy supply conditions. This effectively solves the problem of single-point failure in conventional heavy-load retraction and locking electromechanical actuators, which cannot handle lead screw pair jamming, and enables emergency response with a backup of dissimilar energy.

[0004] The technical solution adopted by this invention to solve its technical problem is: a double-ended locking bearing retractable electromechanical actuator, comprising: a servo motor 20 whose output shaft end gear extends into the sealed cavity of one side of the electromechanical actuator outer cylinder 3 to mesh with a transmission gear 21 to drive the rotation of the lead screw 1 gear pair; a lead screw nut 5 fitted with the lead screw 1; and a piston cylinder 14 that performs telescopic movement in the outer cylinder 1. The outer cylinder 3 is characterized by having an emergency energy inlet 4 radially connected to a high-pressure chamber at its bottom and an upper locking groove 6 located on the inner wall of the high-pressure chamber. The lead screw nut 5 is statically locked by an anti-jamming lock located in the hollow cavity of the piston head through an integrally connected annular cylinder lock on the front end face. During the emergency extension of the selectable piston cylinder 14... High-pressure medium gas enters the high-pressure chamber of the outer cylinder from the emergency energy inlet 4. Through the annular gap channel of the screw nut 5, it drives the anti-jamming lock bushing 17 fitted on the screw 1 to move to the right. This pushes the locking claw ring 19 of the stepped follower sleeve 18, which is locked on the above-mentioned annular cylinder lock, out of the lock ring groove. This causes the upper locking block 7, which is embedded in the upper locking groove 6, to slide out from the conical inclined surface of the locking groove. At the same time, it overcomes the elastic force of the return spring 16 and drives the stepped follower sleeve 18, which is assembled in the front stepped hole of the piston head, to push the piston cylinder 14 to extend over the load. When the piston cylinder 14 extends to the limit position, the lower locking block 12 slides along the outer cylinder 3 and radially locks into the lower locking groove 15 at the end of the cavity. The piston cylinder 14 cannot move and is locked.

[0005] Compared with the prior art, the present invention has the following advantages:

[0006] This invention uses an upper locking bushing 9 to confine the upper locking block 7 installed in the piston cylinder 14 within the upper locking groove 6, thus locking the piston cylinder 14 and preventing it from moving. In the locked state, the upper locking block 7, the upper locking bushing 9, the piston cylinder 14, and the upper locking groove 6 all bear force through surface contact, allowing the actuator to withstand a large locking load in the upper locked state. Similarly, the lower locking bushing 11 confines the lower locking block 12 installed in the piston cylinder 14 within the lower locking groove 15, also locking the piston cylinder 14 and preventing it from moving. In the locked state, the upper locking block 12, the lower locking bushing 11, the piston cylinder 14, and the lower locking groove 15 all bear force through surface contact, allowing the actuator to withstand a large locking load. This improves the electromechanical actuator's retraction and extension capabilities, locking capability, actuator safety, and task reliability.

[0007] This invention incorporates an anti-jamming lock mechanism between the stepped follower sleeve 18 and the lead screw nut 5, which can be unlocked by an emergency medium. Under normal operating conditions, this mechanism is locked. During normal operation, the lead screw nut 5 drives the stepped follower sleeve 18, achieving locking / unlocking and driving the piston cylinder to overcome load movement, resulting in high transmission efficiency. In emergency situations, a dissimilar energy source, such as a high-pressure medium, enters the actuator, pushing the anti-jamming lock bushing 17 out of the inner ring of the stepped follower sleeve 18. This, in turn, causes the stepped follower sleeve 18 and its fitted upper lock bushing 9 to disengage from the inner ring of the upper lock block 7, thereby unlocking the anti-jamming lock and the upper lock. The piston cylinder 14 extends under the action of this dissimilar energy source. In the case of a stuck actuator screw pair, a non-similar energy source can isolate the stuck screw pair from the piston cylinder and unlock the actuator upper lock, pushing the piston cylinder to extend over the load. This solves the problem of single-point failure of the screw pair stuck screw pair that cannot be solved by conventional heavy-duty retraction and heavy-duty locking electromechanical actuators. Attached Figure Description

[0008] Figure 1 This is a cross-sectional view of the double-ended lock-bearing take-up and take-down electromechanical actuator.

[0009] In the diagram: 1. Lead screw, 2. Thrust angular contact ball bearing, 3. Outer cylinder, 4. Emergency power inlet, 5. Lead screw nut, 6. Upper lock groove, 7. Upper lock block, 8. Upper lock block slide groove, 9. Upper lock bushing, 10. Locking spring, 11. Lower lock bushing, 12. Lower lock block, 13. Lower lock groove, 14. Piston cylinder, 15. Lower lock groove, 16. Return spring, 17. Anti-jamming lock bushing, 18. Stepped follower sleeve, 19. Locking claw ring, 20. Servo motor, 21. Transmission gear.

[0010] 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

[0011] See Figure 1In the preferred embodiment described below, a double-ended lock-bearing retractable electromechanical actuator includes: a servo motor 20 whose output shaft end gear extends into the sealed cavity of one side of the electromechanical actuator outer cylinder 3 to mesh with a transmission gear 21, driving the rotation of the lead screw 1 gear pair; a lead screw nut 5 fitted with the lead screw 1; and a piston cylinder 14 that performs telescopic movement in the outer cylinder 1. The outer cylinder 3 is characterized by having an emergency energy inlet 4 radially connected to a high-pressure chamber at its bottom, and an upper locking groove 6 disposed on the inner wall of the high-pressure chamber. The lead screw nut 5 is statically locked by an anti-jamming lock disposed in the hollow cavity of the piston head via an integrally connected ring cylinder lock on the front end face. During the optional emergency extension of the piston cylinder 14, the high-pressure... The medium gas enters the high-pressure chamber of the outer cylinder through the emergency energy inlet 4. Through the annular gap channel of the screw nut 5, it drives the anti-jamming lock bushing 17 fitted on the screw 1 to move to the right. This pushes the locking claw ring 19 of the stepped follower sleeve 18, which is locked on the above-mentioned annular cylinder lock, out of the lock ring groove. This causes the upper locking block 7, which is embedded in the upper locking groove 6, to slide out from the conical inclined surface of the locking groove. At the same time, it overcomes the elastic force of the return spring 16 and drives the stepped follower sleeve 18, which is assembled in the front stepped hole of the piston head, to push the piston cylinder 14 to extend over the load. When the piston cylinder 14 extends to the limit position, the lower locking block 12 slides along the outer cylinder 3 and radially locks into the lower locking groove 15 at the end of the cavity. The piston cylinder 14 cannot move and is locked.

[0012] The anti-jamming lock includes: an upper locking block 7 embedded in the upper locking groove 6 of the high-pressure chamber of the outer cylinder 3, which locks the piston head displacement degree of freedom, and a lower locking block 12 embedded in the lower locking groove 13 of the plug head. The screw nut 5 is connected to the annular cylinder lock buckle on the front end face. The upper locking block 7 and the lower locking block 12 in the upper locking block slide groove 8 of the piston head are connected by the upper locking block 7 and the lower locking block 12 through the symmetrical downward chamfered surface of the upper locking bushing 9 and the cone angle of the end face of the lower locking bushing 11. The locking spring 10 is symmetrically constrained to the annular surface of the stepped step shaft of the stepped follower sleeve 18 and the locking claw ring buckle 19. The locking claw ring buckle 19 cooperates with the necked stepped cylinder of the anti-jamming lock bushing 17 to lock the locking claw ring buckle 19 on the inner annular surface locking groove of the annular cylinder locking claw buckle on the right side of the screw nut 5.

[0013] The locking claw ring 19 of the ring cylinder lock, the anti-jamming lock bushing 17 of the inner ring surface of the locking claw ring 19, the upper locking block 7 embedded in the upper locking groove 6 and the upper locking block slide groove 8 of the piston head ring body, and the lower locking block 12 embedded in the lower locking groove 16 of the adjacent front inner step hole end face of the plug head ring body are constrained by the opposing symmetrical upper locking bushing 9 and lower locking bushing 11 on the stepped step shaft of the stepped follower sleeve 18 and the locking spring 10 on the claw ring surface. The elastic force provided by the locking spring 10 is maintained between the stepped step surface of the stepped follower sleeve 18 and the annular hole formed by the opposing symmetrical upper locking bushing 9 and lower locking bushing 11.

[0014] The upper lock block 7, which is embedded in the upper lock block groove 8, has the same conical chamfer. The lower lock bushing 9 and the lower lock bushing 11 are symmetrical to each other, and the back end has a chamfered surface that matches the chamfer of the upper lock block 7 and the lower lock block 12.

[0015] The stepped follower sleeve 18 and the locking claw ring buckle 19 are fitted together with the anti-jamming locking bushing 17 and the bidirectional flanged ring sleeve, locking the locking claw ring buckle 19 on the ring sleeve in the ring sleeve locking arc ring lock groove of the screw nut 5, thus locking the screw nut 5 and the stepped follower sleeve 18 together.

[0016] The double-flanged sleeve sleeve is fitted with the lead screw 1 and is limited in the inner ring groove of the anti-jamming lock bushing 17. The front end ring sealing step protrusion of the anti-jamming lock bushing 17 extends into the moving cavity of the piston cylinder 14 through the piston head end wall hole, and constrains the return spring 16 in the small end spacer cavity of the piston cylinder 14. Together with the anti-jamming lock, it forms an anti-jamming lock mechanism with double-ended lock bearing the piston cylinder 14 emergency retraction and locking, unlocking and extension of the outer cylinder 3 cavity end ring sealing outlet hole.

[0017] The lead screw 1, through the thrust angular contact ball bearing 2 assembled in the bearing housing cavity of the outer cylinder 3, fits the tail stepped shaft ring groove and extends into the bottom hole of the piston cylinder 14 through the stepped follower sleeve 18 and the anti-jamming lock bushing 17.

[0018] When the actuator retracts the piston cylinder normally, the lead screw 1 rotates, and the lead screw nut 5 drives the anti-jamming lock of the double-ended load-bearing device. The lower step of the stepped follower sleeve 18 drives the piston cylinder 14 to retract over the load. When the piston cylinder is lowered normally, the lead screw nut 5 pushes the anti-jamming lock of the double-ended load-bearing device. The upper step of the stepped follower sleeve 18 drives the upper lock bushing 9 to disengage from the inner ring of the upper lock block 7. The lower step of the stepped follower sleeve 18 pushes the piston cylinder 14 to extend over the load. At the same time, the upper lock block 7 slides radially along the upper lock block slide groove 8 and slides out from the inclined surface of the upper lock groove 6. The piston cylinder 14 extends to the limit position. The lower lock block 12 is pushed by the lower lock bushing 11 under the elastic force of the locking spring 10. It slides radially along the lower lock groove 13 and is locked into the lower lock groove 15. The lower lock bushing 11 is then locked into the inner ring of the lower lock block 12. The piston cylinder 14 cannot move and is locked.

[0019] When the piston cylinder needs to be extended in an emergency, a non-electrical energy source, such as high-pressure medium gas, enters the outer cylinder cavity through the emergency energy inlet 4. Under the action of gas pressure, the anti-jamming lock bushing 17 overcomes the elastic force of the return spring 16. After the upper step disengages from the inner ring of the claw end of the stepped follower sleeve 18, the middle step of the anti-jamming lock bushing 17 drives the stepped follower sleeve 18, and the upper step drives the upper lock bushing 9 to disengage from the inner ring of the upper lock block 7. The high-pressure gas pushes the piston cylinder 14 to extend over the load. At the same time, the upper lock block 7 slides radially along the upper lock block slide groove 8 and slides out from the inclined surface of the upper lock groove 6. The piston cylinder 14 extends to the limit position. Under the action of the locking spring 10, the lower lock block 12 is pushed by the lower lock bushing 11, slides radially along the lower lock groove 13 and is locked into the lower lock groove 15. The lower lock bushing 11 is then locked into the inner ring of the lower lock block 12, and the piston cylinder 14 cannot move and is locked.

[0020] Although embodiments of the present invention have been shown and described above in detail, the description of the embodiments is only for the purpose of helping to understand the present invention; at the same time, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the content of this specification should not be construed as limiting the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A dual end-lock bearing electro-mechanical actuator, comprising: The output shaft end gear extends into the sealed cavity of the outer cylinder (3) of the electromechanical actuator on one side, meshing with the transmission gear (21) to drive the servo motor (20) to rotate the lead screw (1) gear pair, the lead screw nut (5) sleeved with the lead screw (1), and the piston cylinder (14) that performs telescopic movement in the outer cylinder (1). The outer cylinder (3) has an emergency energy inlet (4) that is radially connected to the high-pressure cavity at its bottom and an upper locking groove (6) set on the inner wall of the high-pressure cavity. The lead screw nut (5) is statically locked by the anti-jamming lock set in the hollow cavity of the piston head through the ring cylinder lock buckle integrally connected on the front end face. During the emergency extension of the piston cylinder (14), the high-pressure medium gas enters the high-pressure outer cylinder from the emergency energy inlet (4). The cavity, through the annular seam channel of the screw nut (5), drives the anti-jamming lock bushing (17) fitted on the screw (1) to move to the right, pushing the locking claw ring (19) of the stepped follower sleeve (18) locked on the above-mentioned annular cylinder lock out of the buckle lock groove, driving the upper locking block (7) embedded in the upper locking groove (6) to slide out from the conical inclined surface of the locking groove, and at the same time overcoming the elastic force of the return spring (16), driving the stepped follower sleeve (18) assembled in the front stepped hole of the piston head, pushing the piston cylinder (14) to overcome the load and extend. The piston cylinder (14) extends to the limit position, and the lower locking block (12) slides along the outer cylinder (3) and radially jams into the lower locking groove (15) at the end of the cavity, so that the piston cylinder (14) cannot move and is locked. The anti-jamming lock includes: an upper locking block (7) embedded in the upper locking groove (6) of the high-pressure chamber of the outer cylinder (3) to lock the displacement degree of the piston head, and a lower locking block (12) embedded in the lower locking groove (13) of the plug head. The screw nut 5 is connected to the ring cylinder lock on the front end face. The upper locking block (7) and the lower locking block (12) in the upper locking block slide groove (8) of the piston head are connected to the upper locking bushing (9) and the lower locking bushing (11) end face cone angle slope through the symmetrical downward cut angle slope. The locking spring (10) is symmetrically constrained to the stepped step shaft of the stepped follower sleeve (18) and the ring surface of the locking claw ring buckle (19). The locking claw ring buckle (19) is connected to the anti-jamming lock bushing (17) necked step cylinder to lock the locking claw ring buckle (19) on the inner ring surface locking groove of the ring cylinder claw buckle on the right side of the screw nut (5).

2. The double-ended lock-bearing retractable electromechanical actuator as described in claim 1, characterized in that: The locking claw ring (19) locked by the ring cylinder lock, the anti-jamming lock bushing (17) on the inner ring surface of the locking claw ring (19), the upper locking block (7) embedded in the upper locking groove (6) and the upper locking block slide groove (8) of the piston head ring body, and the lower locking block (12) embedded in the lower locking groove of the adjacent front inner step hole end face of the plug head ring body, are constrained by the opposing symmetrical upper locking bushing (9) and lower locking bushing (11) on the stepped step shaft of the stepped follower sleeve (18) and the locking spring (10) on the ring surface of the claw ring. The elastic force provided by the locking spring (10) is maintained between the stepped step surface of the stepped follower sleeve (18) and the annular hole formed by the opposing symmetrical upper locking bushing (9) and lower locking bushing (11).

3. The double-ended lock-bearing retractable electromechanical actuator as described in claim 2, characterized in that: The upper lock block (7) embedded in the upper lock block groove (8) has the same conical chamfer. The upper lock bushing (9) and the lower lock bushing (11) are symmetrical to each other, and the back end has a chamfered surface that matches the chamfer of the upper lock block (7) and the lower lock block (12).

4. The double-ended lock-bearing retractable motor actuator as described in claim 2, characterized in that: The stepped follower sleeve (18) and the locking claw ring (19) are fitted with the anti-jamming locking bushing (17) and the double-sided flanged ring sleeve, locking the locking claw ring (19) on the ring cylinder in the ring cylinder locking arc ring groove of the screw nut (5), thus locking the screw nut (5) and the stepped follower sleeve (18) together.

5. The double-ended lock-bearing retractable motor actuator as described in claim 4, characterized in that: The double-sided flanged sleeve sleeve screw (1) is limited in the inner ring groove of the anti-jamming lock bushing (17). The front end ring sealing step protrusion of the anti-jamming lock bushing (17) extends into the piston cylinder (14) motion cavity through the piston head end wall hole, constraining the return spring (16) in the small end spacer cavity of the piston cylinder (14). Together with the anti-jamming lock, it forms a double-ended lock bearing anti-jamming lock mechanism for emergency locking, unlocking and extension of the piston cylinder (14) to the outer cylinder (3) cavity end ring sealing outlet hole.

6. The double-ended lock-bearing retractable motor actuator as described in claim 1, characterized in that: The lead screw (1) passes through the thrust angular contact ball bearing (2) assembled in the bearing housing cavity of the outer cylinder (3) and inserts the tail stepped shaft ring groove into the bottom hole of the piston cylinder (14) through the stepped follower sleeve (18) and the anti-jamming lock bushing (17).

7. The double-ended lock-bearing retractable electromechanical actuator as described in claim 1, characterized in that: When the actuator retracts the piston cylinder normally, the lead screw (1) rotates, and the lead screw nut (5) drives the double-end lock anti-jamming lock. The lower step of the stepped follower sleeve (18) drives the piston cylinder (14) to retract over the load. When the piston cylinder is lowered normally, the lead screw nut (5) pushes the double-end lock anti-jamming lock. The upper step of the stepped follower sleeve (18) drives the upper lock bushing (9) to disengage from the inner ring of the upper lock block (7). The lower step of the stepped follower sleeve (18) pushes the piston cylinder (14). Overcoming the load extension, the upper locking block (7) slides radially along the upper locking block groove (8) and slides out from the chamfered surface of the upper locking groove (6). The piston cylinder (14) extends to the limit position. The lower locking block (12) is pushed by the lower locking bushing (11) under the elastic force of the locking spring (10), slides radially along the lower locking groove (13) and is locked into the lower locking groove (15). The lower locking bushing (11) then locks into the inner ring of the lower locking block (12). The piston cylinder (14) cannot move and is locked.

Images