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CN-224211270-U - Large-load bidirectional driver

CN224211270UCN 224211270 UCN224211270 UCN 224211270UCN-224211270-U

Abstract

The utility model provides a high-load two-way driver which comprises a shell, two sets of SMA wire-spring structures, taper pins, a retraction spring, a locking sliding block, a steel ball and a double-inclined-plane wedge block. The rectangular cavity of the shell is internally provided with a first set of SMA-spring structure for driving the locking slide block, the L-shaped cavity is internally provided with a taper pin and a second set of SMA-spring structure for driving the double-inclined-plane wedge block, when the taper pin is required to extend, the first set of SMA-spring structure is electrified to drive the locking slide block to move right, the limit on the steel ball is relieved, the compression spring of the second set of SMA-spring structure pushes the double-inclined-plane wedge block to move left so as to drive the taper pin to push out and maintain the extended state by means of inclined-plane friction self-locking, when the taper pin is required to retract, the second set of SMA-spring structure is electrified to drive the double-inclined-plane wedge block to move right, the retraction spring pulls the taper pin back, meanwhile, the steel ball limits the double-inclined-plane wedge block again, and the taper pin is stabilized in the retracted state. The utility model has the advantages of simple and compact structure, light weight, strong bearing capacity and high driving reliability.

Inventors

  • FU JIALI
  • SUN RUIJIE

Assignees

  • 航迹通(上海)信息技术有限公司

Dates

Publication Date
20260508
Application Date
20250605

Claims (6)

  1. 1. A large-load two-way driver is characterized by comprising an SMA-spring structure, a taper pin (1), a shell (2), a locking sliding block (3), a double-inclined-plane wedge block (6), a steel ball (7) and a retraction spring (10), The SMA-spring structure comprises two sets, wherein the first set of SMA-spring structure consists of an SMA wire A (5) and a locking spring (4) and is used for driving a locking sliding block (3), and the second set of SMA-spring structure consists of an SMA wire B (9) and a compression spring (8) and is used for driving a double-inclined-plane wedge block (6); The taper pin (1) is used for outputting locking force to the outside, the lower end of the taper pin is of a double-inclined-plane structure and is matched with the double inclined planes at the left upper part of the double-inclined-plane wedge block (6), and the bottom of the taper pin (1) is connected with the retraction spring (10); The shell (2) is of a double-cavity structure and comprises a rectangular cavity (201) and an L-shaped cavity (202), the right ends of the two cavities are insulated, a first set of SMA-spring structure is arranged in the rectangular cavity (201), a taper pin (1) is contained in the left vertical section of the L-shaped cavity (202), a second set of SMA-spring structure is arranged in the right horizontal section of the L-shaped cavity, the left end of an SMA wire A (5) is fixed on a locking slide block (3), the right end of the SMA wire A passes through a locking spring (4) to be fixed on the insulating end of the rectangular cavity (201), the left end of an SMA wire B (9) is fixed on a double-inclined-surface wedge block (6), the right end of the SMA wire B passes through a pressing spring (8) to be fixed on the insulating end of the L-shaped cavity (202), circular through holes (203) with diameters larger than those of steel balls (7) are formed in the boundary walls of the rectangular cavity (201) and the L-shaped cavity (202), and trapezoid grooves for containing the steel balls (7) are respectively formed in the locking slide block (3) and the double-inclined-surface wedge block (6); when the taper pin needs to be extended, the SMA wire A (5) is electrified and heated to shrink, the locking slide block (3) is pulled to move rightwards, the steel ball (7) is extruded into the groove of the locking slide block (3) by the double-inclined-plane wedge block (6) under the action of the restoring force of the compression spring (8), the double-inclined-plane wedge block (6) loses constraint and continues to move leftwards under the action of the compression spring (8), the taper pin (1) is quickly jacked up by the large inclined plane of the double-inclined-plane wedge block (6) in the first half, and friction self-locking is formed after the small inclined plane is jacked up, so that the taper pin (1) is stabilized in an extended state; When the taper pin needs to be retracted, the SMA wire B (9) is electrified and heated to shrink, the double-inclined-plane wedge block (6) is pulled to move rightwards, the steel ball (7) is extruded into the groove of the double-inclined-plane wedge block (6) by the left movement of the locking sliding block (3) under the action of the restoring force of the locking spring (4), meanwhile, the locking sliding block (3) is pressed leftwards by the locking spring (4), the limit of the steel ball (7) is completed, further, the double-inclined-plane wedge block (6) is locked, the taper pin (1) moves downwards under the action of the retraction spring, and retraction is completed and stabilized in a retraction state.
  2. 2. The high load bi-directional driver according to claim 1, characterized in that the large angle bevel of the double bevel wedge (6) is designed to be 50-60 ° and the small angle bevel is designed to be 8-15 °.
  3. 3. A high load bi-directional driver according to claim 1, characterized in that the spring force of the hold-down spring (8) is greater than the locking spring (4) in the two sets of SMA-spring structures.
  4. 4. A high load two-way drive according to claim 1, characterized in that the SMA wire a (5) has a smaller diameter than the SMA wire B (9) in the two sets of SMA-spring structures.
  5. 5. The high-load bidirectional driver according to any one of claims 1 to 4, wherein the right end of the housing chamber is insulated by fixing an insulating support plate (11), and the insulating support plate is made of a high-strength insulating material.
  6. 6. The high-load bidirectional driver according to claim 1, wherein the upper end of the taper pin (1) is tapered, so that the possibility of unexpected clamping stagnation caused by friction between the taper pin (1) and the inner wall of the shell (2) in the extending process is prevented, and smooth sliding is ensured.

Description

Large-load bidirectional driver Technical Field The utility model relates to the technical field of locking devices, in particular to a locking device capable of realizing bidirectional driving. Background The space unfolding mechanism of the spacecraft needs to be locked in an unfolding state after being unfolded in place in an orbit, when the spacecraft is in maneuvering orbit, the unfolding mechanism needs to be folded, at the moment, the locking device is firstly unlocked, the folding state of the unfolding mechanism needs to be locked and limited after the unfolding mechanism is folded in place, and after orbit transformation is completed, the unfolding mechanism needs to be unfolded again, and the locking device locks the unfolding state again. This requires the locking device to have bi-directional drive capability and provide both locked and unlocked positions. The utility model patent CN214729790U in the prior art provides a memory metal two-way driver (shown in figure 1), which adopts two opposite-pull shape memory alloy wires (SMA wires) to directly drive a sliding pin with two trapezoid grooves to move, realizes two-way driving, and completes the switching of the two states of extending and retracting the sliding pin, thereby outputting two working states of locking position and unlocking position. The driver can realize a bidirectional driving function, but has limited bearing capacity, and when the sliding pin is in an extended state, if the sliding pin is compressed by excessive external force, the inclined surface of the trapezoid groove can extrude the steel ball again, so that the sliding pin is out of constraint and is retracted into the retainer, and therefore, the sliding pin of the driver is difficult to maintain in a stable extended state when bearing a large load. In addition, the sliding pin is ejected out completely by virtue of driving force generated by electrifying and shrinking of the SMA wire in the process of stretching out the sliding pin, so that the ejection force is small, and the sliding pin cannot be used for a large-scale expandable structure with a large demand on the ejection force. Patent application CN101435452a provides a tightening device driven by a shape memory alloy (as shown in fig. 2), which uses two sets of SMA-spring drivers to perform a spaced action, wherein a second SMA-spring structure is used to lock a first SMA-spring structure, the first SMA-spring structure pushes an elastic claw to move upwards through a double-wedge structure to output a tightening force, and the two sets of SMA-spring structures are respectively electrified, so that the elastic claw can be controlled to complete tightening or retraction of a structural member to release the constraint. The jacking device is complex in structure and limited in driving reliability, and particularly, the first wedge block driven by the first SMA-spring structure limits the shrinkage position of the second wedge block in a mode of inserting the cylindrical boss into the sliding groove of the second wedge block, the contact surface between the cylindrical boss and the sliding groove is large, the friction resistance is large, the spring force of the first spring is overcome when the first SMA shrinks and pulls up the first wedge block, the friction resistance is overcome, and the conditions that driving fails easily and shrinkage state constraint cannot be released are easily caused. Disclosure of Invention In order to overcome the defects of low bearing capacity, limited reliability, complex structure and the like of the two-way driver, the utility model provides the large-load SMA two-way driver which has simple structure and high reliability and combines friction self-locking and spring propping. The technical scheme adopted by the utility model is that the high-load two-way driver comprises a shell, an SMA wire-spring structure, a taper pin, a retraction spring, a locking sliding block, a steel ball and a double-inclined-plane wedge block. The taper pin is a component for outputting locking force outwards, the upper end of the taper pin is conical, so that the possibility of unexpected clamping stagnation caused by friction between the taper pin and the inner wall of the shell is prevented, smooth sliding is ensured, the double-inclined-surface structure of the lower end of the taper pin is used for being matched with the double inclined surfaces of the wedge part of the double-inclined-surface wedge, and the bottom of the taper pin is connected with a retraction spring for providing pulling force for retracting the taper pin into the shell. The SMA-spring structure comprises two sets, wherein the first set of SMA-spring structure consists of an SMA wire A and a locking spring for driving the locking sliding block, and the second set of SMA-spring structure consists of an SMA wire B and a compression spring for driving the double-inclined-plane wedge block. The shell is of a double-cavity structu