阅读说明：本技术 一种由sma丝驱动的空间解锁装置 (Space unlocking device driven by SMA wire ) 是由 孙健 刘彦菊 周宝 冷劲松 于 2018-06-29 设计创作，主要内容包括：本发明提供了一种由SMA丝驱动的空间解锁装置,包括顶盖、外罩、底座、SMA合金丝、轴衬、滚珠套、驱动块、恢复弹簧、顶块、上压缩弹簧、下压缩弹簧、上限位滚珠、下限位滚珠和分成若干瓣的分瓣螺母,轴衬、滚珠套、驱动块、恢复弹簧、顶块、上压缩弹簧、下压缩弹簧、上限位滚珠、下限位滚珠和分瓣螺母均设置在由顶盖、外罩、底座组成的腔体结构内,SMA合金丝一端依次穿过底座和下压缩弹簧与驱动块底部固定连接后再依次穿过下压缩弹簧和底座而穿出腔体结构,SMA合金丝的两端与外部电源连接,轴衬设置在滚珠套和外罩之间。本发明采用SMA直线驱动方式,具有低冲击,解锁时间短,运动精度高,低摩擦,无污染可重复使用的优点。(The invention provides a space unlocking device driven by an SMA wire, which comprises a top cover, an outer cover, a base, the SMA wire, a shaft bushing, a ball sleeve, a driving block, a restoring spring, a top block, an upper compression spring, a lower compression spring, an upper limiting ball, a lower limiting ball and a split nut divided into a plurality of segments. The invention adopts the SMA linear driving mode and has the advantages of low impact, short unlocking time, high motion precision, low friction, no pollution and reusability.)

1. A spatial unlocking device driven by SMA wires is characterized in that: the device comprises a cavity structure consisting of a top cover (14), an outer cover (3) and a base (1) from top to bottom, SMA alloy wires (8), a bushing (4), a ball sleeve (10), a driving block (6), a recovery spring (2), a top block (12), an upper compression spring (11), a lower compression spring (9), an upper limiting ball (13), a lower limiting ball (5) and a split nut (7) divided into a plurality of lobes, wherein the bushing, the ball sleeve (10), the driving block (6), the recovery spring (2), the top block (12), the upper compression spring (11), the lower compression spring (9), the upper limiting ball (13), the lower limiting ball (5) and the split nut (7) divided into the plurality of lobes are all arranged in the cavity structure;

the bottom of the ball sleeve (10) is fixed on the base (1), the driving block (6) and the lower compression spring (9) are arranged inside the ball sleeve (10), the upper end of the lower compression spring (9) abuts against the driving block (6), the lower end of the lower compression spring (9) abuts against the base (1), the lower limiting ball (5) is arranged in a through hole in the side wall of the middle of the ball sleeve (10), a first groove (16) for accommodating the lower limiting ball (5) is formed in the side surface of the driving block (6), an upper compression spring accommodating groove is formed in the top of the ball sleeve (10), the upper end of the upper compression spring (11) abuts against the lower surface of the top block (12), and the lower end of the upper compression spring accommodating groove abuts against the bottom of the upper compression spring accommodating groove;

one end of the SMA alloy wire (8) sequentially penetrates through the base (1) and the lower compression spring (9) to be fixedly connected with the bottom of the driving block (6) and then sequentially penetrates through the lower compression spring (9) and the base (1) to penetrate out of the cavity structure, two ends of the SMA alloy wire (8) are connected with an external power supply, two ends of the SMA alloy wire (8) are fixed on the base (1), the bushing (4) is arranged in the gap between the ball sleeve (10) and the outer cover (3), the upper part of the inner side wall of the bushing (4) is provided with a second groove for accommodating an upper limiting ball (13), the middle part of the inner side wall of the bushing (4) is provided with a third groove (17) for accommodating a lower limiting ball (5), the restoring spring (2) is sleeved on the outer side wall of the shaft bushing (4), the upper end of the restoring spring (2) abuts against the shaft bushing (4), and the lower end of the restoring spring abuts against the base (1);

the inner side of the split nut (7) is provided with a thread connected with a bolt (15), the outer side surface of the split nut (7) is provided with a fourth groove (18) for accommodating an upper limiting ball (13), the upper end of the split nut (7) is matched with the top cover (14) through a conical surface, the lower end of the split nut (7) is matched with the upper part of the top block (12) through a conical surface, and the inclined directions of the conical surfaces between the top block (12) and the top cover (14) and the split nut (7) are suitable for promoting the split nut (7) to be separated;

the position of the through hole is matched with the positions of the first groove (16) and the third groove (17), the position of the second groove is matched with the position of the fourth groove (18), the lower end of the bolt (15) is abutted against the top block (12), and the upper end of the bolt penetrates out of the top cover (14);

in a locking state, namely an SMA alloy wire (8) is in a non-electrified state, the driving block (6) is positioned at the upper part inside the ball sleeve (10) under the support of the lower compression spring (9), the first groove (16) on the driving block (6) is higher than the through hole on the ball sleeve (10), the through hole of the ball sleeve (10) is communicated with the third groove (17) in the middle of the inner side wall of the bushing (4), the lower limiting ball (5) is arranged in the through hole and the third groove (17), as the bushing (4) is subjected to the restoring force of the restoring spring (2), a radial force is applied to the lower limiting ball (5) in the third groove (17), and as the lower limiting ball (5) is subjected to the radial constraint of the driving block (6), the radial movement of the lower limiting ball (5) is limited, so that the lower limiting ball (5) has an axial constraint force on the bushing (4) and the axial movement of the bushing (4) is limited, the upper limiting ball (13) is arranged in a second groove in the upper part of the inner side wall of the bushing (4), the bushing (4) applies radial force to the upper limiting ball (13) to radially restrict the split nut (7) to enable the split nut (7) to keep folding;

in an unlocking state, namely, the SMA alloy wire (8) is electrified to be subjected to phase change and contract, the driving block (6) moves downwards, the lower compression spring (9) is compressed, when the first groove (16) in the driving block (6) moves downwards and is communicated with the through hole in the ball sleeve (10), the lower limiting ball (5) enters the first groove (16), the axial constraint force on the bushing (4) is relieved, the bushing (4) moves upwards, the upper limiting ball (13) is driven to enter the fourth groove (18) in the split nut (7), the radial constraint on the split nut (7) is relieved, the split nut (7) is radially separated under the action of the ejector block (12), and the bolt (15) is ejected out by the ejector block (12) due to the axial pressure exerted on the ejector block (12) and the bolt (15) by the upper compression spring (11), and then unlocking is completed.

2. The SMA wire-driven space unlocking apparatus as defined in claim 1, wherein: the driving block (6) is composed of two identical semi-cylindrical blocks, an SMA alloy wire accommodating groove (19) is formed in the rectangular surface of each semi-cylindrical block, a semi-first groove (16) is formed in the cylindrical surface of each semi-cylindrical block, and the two semi-cylindrical blocks are attached together to form a complete first groove (16).

3. The SMA wire-driven space unlocking apparatus as defined in claim 2, wherein: the SMA alloy wires (8) are divided into arc shapes in the SMA alloy wire accommodating grooves (19), and the rest parts are in a linear state.

4. The SMA wire-driven space unlocking apparatus as defined in claim 3, wherein: the through holes in the ball sleeve (10) are uniformly provided with a plurality of lower limiting balls (5) in each through hole.

5. The SMA wire-driven space unlocking apparatus as defined in claim 4, wherein: the first groove (16), the second groove, the third groove (17) and the fourth groove (18) are all annular grooves, and the size of the notch of each annular groove is wider than that of the bottom of each annular groove.

6. The SMA wire-driven space unlocking apparatus as defined in claim 5, wherein: the bottom of the ejector block (12) is provided with a guide bulge matched with the upper compression spring accommodating groove, and the top of the ejector block (12) is provided with a plane which is abutted to the bolt (15).

7. A space unlocking device driven by SMA wire according to any one of claims 1-6, wherein: the method is characterized in that: the outer surface of the bushing (4) is provided with a return spring (2) for abutting against the table.

8. A SMA wire-driven space unlocking device according to claim 7, wherein the split nut (7) has 3 or 4 pieces.

9. The SMA wire-actuated spatial unlocking device of claim 8, wherein: the unlocking device is made of light alloy materials.

10. The SMA wire-actuated spatial unlocking device of claim 9, wherein: the base (1) is provided with a ceramic insulating layer.

Technical Field

The invention belongs to the field of space unlocking devices, and particularly relates to a space unlocking device driven by an SMA wire.

Background

After the satellite is launched, a plurality of auxiliary devices such as an antenna and a solar panel are required to be successfully separated from a parent body so as to successfully complete the on-orbit task, most of releasing devices are initiating devices, the action time is short, the size is small, the smaller energy input is the advantages, however, the releasing devices easily cause higher impact load and space pollution, the treatment cost is huge, and therefore, a separating device capable of replacing the traditional initiating device is required to be researched, and the separating device has the advantages of low impact load, no pollution and reusability compared with the initiating device. Due to the unique shape memory performance and large output strain of the shape memory alloy SMA, under the deformation condition, when the temperature exceeds the corresponding phase transition temperature, the shape memory alloy SMA can recover the original shape, the recovery deformation can be repeated under a certain condition, and the maximum recovery strain can reach 8 percent, so the SMA can be used as a driving source. The existing split nut locking mechanism has the advantages of large impact, nonlinear SMA drive, small driving force and difficulty in guaranteeing the motion precision of the ball, and the split nut locking mechanism has the advantages of low impact, short unlocking time, high motion precision, low friction, no pollution and reusability by adopting an SMA linear drive mode.

Disclosure of Invention

In view of the above, the invention aims to provide a space unlocking device driven by an SMA wire, which adopts an SMA linear driving mode and has the advantages of low impact, short unlocking time, high motion precision, low friction, no pollution and reusability.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a space unlocking device driven by an SMA wire comprises a cavity structure, the SMA alloy wire, a bushing, a ball sleeve, a driving block, a restoring spring, a top block, an upper compression spring, a lower compression spring, an upper limiting ball, a lower limiting ball and a split nut which is divided into a plurality of lobes, wherein the cavity structure consists of a top cover, an outer cover and a base from top to bottom;

the bottom of the ball sleeve is fixed on the base, the driving block and the lower compression spring are arranged in the ball sleeve, the upper end of the lower compression spring is abutted against the driving block, the lower end of the lower compression spring is abutted against the base, the lower limiting ball is arranged in a through hole in the side wall of the middle part of the ball sleeve, a first groove for containing the lower limiting ball is arranged on the side surface of the driving block, an upper compression spring containing groove is arranged at the top of the ball sleeve, the upper end of the upper compression spring is abutted against the lower surface of the top block, and the lower end of the upper compression spring is abutted against the bottom of the upper compression spring containing groove;

one end of the SMA alloy wire sequentially penetrates through the base and the lower compression spring to be fixedly connected with the bottom of the driving block and then sequentially penetrates through the lower compression spring and the base to penetrate out of the cavity structure, two ends of the SMA alloy wire are connected with an external power supply, two ends of the SMA alloy wire are fixed on the base, the shaft bushing is arranged in a gap between the ball sleeve and the outer cover, a second groove for accommodating an upper limiting ball is arranged at the upper part of the inner side wall of the shaft bushing, a third groove for accommodating a lower limiting ball is arranged in the middle of the inner side wall of the shaft bushing, the recovery spring is sleeved on the outer side wall of the shaft bushing, the upper end of the recovery spring abuts against the shaft bushing, and the lower end of the recovery spring abuts against the;

the inner side of the split nut is provided with a thread for connecting a bolt, the outer side surface of the discrimination nut is provided with a fourth groove for accommodating an upper limiting ball, the upper end of the split nut is matched with the top cover by a conical surface, the lower end of the split nut is matched with the upper part of the top block by a conical surface, and the inclined directions of the conical surfaces between the top block and the split nut and between the top cover and the split nut are suitable for promoting the split nut to be separated;

the position of the through hole is matched with the positions of the first groove and the third groove, the position of the second groove is matched with the position of the fourth groove, the lower end of the bolt abuts against the top block, and the upper end of the bolt penetrates out of the top cover;

in a locking state, namely an SMA alloy wire is in a non-energized state, a driving block is positioned at the upper part inside a ball sleeve under the support of a lower compression spring, a first groove on the driving block is higher than a through hole on the ball sleeve, the through hole of the ball sleeve is communicated with a third groove in the middle of the inner side wall of a bushing, a lower limiting ball is arranged in the through hole and the third groove, as the bushing is subjected to the restoring force of a restoring spring, a radial force is exerted on the lower limiting ball in the third groove, as the lower limiting ball is radially constrained by the driving block, the radial movement of the lower limiting ball is limited, the lower limiting ball is caused to have an axial constraining force on the bushing, the axial movement of the bushing is limited, the upper limiting ball is arranged in a second groove in the upper part of the inner side wall of the bushing, the bushing applies the radial force to the upper limiting ball, and the split nut is radially constrained;

in an unlocking state, namely, the SMA alloy wire is electrified to be subjected to phase change and contract, the driving block moves downwards, the lower compression spring is compressed, when the first groove in the driving block moves downwards and is communicated with the through hole in the ball sleeve, the lower limiting ball enters the first groove, the axial constraint force on the bushing is relieved, the bushing moves upwards, the upper limiting ball is driven to enter the fourth groove in the split nut, the radial constraint on the split nut is relieved, the split nut is radially separated under the action of the jacking block, the bolt is ejected out by the jacking block due to the axial pressure of the upper compression spring on the jacking block and the bolt, and the unlocking is completed at the moment.

Furthermore, the driving block is composed of two identical semi-cylindrical blocks, an SMA alloy wire accommodating groove is formed in the rectangular surface of each semi-cylindrical block, a semi-first groove is formed in the cylindrical surface of each semi-cylindrical block, and the two semi-cylindrical blocks are attached together to form a complete first groove.

Furthermore, the SMA alloy wires are divided into arc shapes in the SMA alloy wire accommodating grooves, and the rest parts of the SMA alloy wires are in a linear state.

Further, the through-hole on the ball cover evenly sets up a plurality ofly, and all has a lower spacing ball in each through-hole, also evenly sets up a plurality ofly.

Furthermore, the first groove, the second groove, the third groove and the fourth groove are all annular grooves, and the size of the notch of each annular groove is wider than that of the bottom of each annular groove.

Furthermore, the top block bottom is equipped with last compression spring holding tank complex direction arch, the top block top is equipped with the plane that offsets with the bolt.

Further, the outer surface of the bushing is provided with a return spring abutting table.

Further, the split nut is 3 or 4.

Further, the unlocking device is made of light alloy materials.

Furthermore, a ceramic insulating layer is arranged on the base.

Compared with the prior art, the space unlocking device driven by the SMA wire has the following advantages:

according to the space unlocking device driven by the SMA wire, the lower limiting balls are arranged in the ball sleeve, and the ball sleeve exerts axial constraint on the ball sleeve, so that the axial movement synchronism of the lower balls is ensured, and the structure can greatly improve the unlocking precision; in an unlocking state, the lower limiting ball enters the ball sleeve and the driving block, the axial constraint force on the bushing is relieved, the compression energy of the recovery spring is partially consumed by the kinetic energy of the ball, the impact force of the bushing on the upper limiting ball can be reduced, and the impact of the upper limiting ball on the split nut is further reduced, so that the structure has the advantage of low impact; the SMA alloy wire is used as a driving element, the SMA alloy wire is divided into an arc shape in the SMA alloy wire accommodating groove, the output displacement can be increased, the rest parts are in a linear state, a linear driving mode and the optimized depth of the ball sleeve are adopted, the driving displacement and the driving force of the SMA alloy wire can be ensured, and the unlocking time is greatly reduced; the upper end and the lower end of the split nut are respectively matched with the end cover and the top block through conical surfaces, so that the split nut is guaranteed to be smoothly separated and folded, and the separation reliability is improved; the ejector block and the upper compression spring act together to assist the split nut in separation, so that the success rate of separation is further improved, and the reliability is improved; the upper end and the lower extreme of split nut all cooperate with top cap and kicking block respectively with the conical surface, and the kicking block bottom is equipped with last compression spring holding tank complex direction arch, and this kind of setting has from the centering action for when mechanism bears the big vibration and the impact load of any direction, can not have the part to take place the motion and cause the connection failure, and anti-vibration and impact capacity are strong.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic structural diagram of a spatial unlocking device driven by an SMA wire according to an embodiment of the present invention;

FIG. 2 is a cross-sectional view of a locked state of a SMA wire-driven spatial unlocking device according to an embodiment of the invention;

FIG. 3 is a cross-sectional view of an unlocked state of a spatial unlocking device driven by an SMA wire according to an embodiment of the invention;

fig. 4 is a schematic structural diagram of a semi-cylindrical block in a spatial unlocking device driven by an SMA wire according to an embodiment of the present invention.

Description of reference numerals:

1-base, 2-restoring spring, 3-outer cover, 4-bushing, 5-lower limiting ball, 6-driving block, 7-split nut, 8-SMA alloy wire, 9-lower compression spring, 10-ball sleeve, 11-upper compression spring, 12-top block, 13-upper limiting ball, 14-top cover, 15-bolt, 16-first groove, 17-third groove, 18-fourth groove and 19-SMA alloy wire accommodating groove.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

As shown in fig. 1-4, a space unlocking device driven by SMA wire includes a cavity structure composed of a top cover 14, a housing 3 and a base 1 from top to bottom, an SMA alloy wire 8, a bushing 4, a ball sleeve 10, a driving block 6, a restoring spring 2, a top block 12, an upper compression spring 11, a lower compression spring 9, an upper limiting ball 13, a lower limiting ball 5 and a split nut 7 divided into a plurality of lobes, wherein the bushing, the ball sleeve 10, the driving block 6, the restoring spring 2, the top block 12, the upper compression spring 11, the lower compression spring 9, the upper limiting ball 13, the lower limiting ball 5 and the split nut 7 divided into a plurality of lobes are all arranged in the cavity structure;

the bottom of the ball sleeve 10 is fixed on the base 1, the driving block 6 and the lower compression spring 9 are arranged in the ball sleeve 10, the upper end of the lower compression spring 9 is abutted against the driving block 6, the lower end of the lower compression spring 9 is abutted against the base 1, the lower limiting ball 5 is arranged in a through hole in the side wall of the middle part of the ball sleeve 10, a first groove 16 for accommodating the lower limiting ball 5 is arranged on the side surface of the driving block 6, an upper compression spring accommodating groove is arranged at the top of the ball sleeve 10, the upper end of the upper compression spring 11 is abutted against the lower surface of the top block 12, and the lower end of the upper compression spring 11 is abutted against the groove bottom of the upper compression spring accommodating groove;

one end of the SMA alloy wire 8 sequentially penetrates through the base 1 and the lower compression spring 9 to be fixedly connected with the bottom of the driving block 6 and then sequentially penetrates through the lower compression spring 9 and the base 1 to penetrate out of the cavity structure, two ends of the SMA alloy wire 8 are respectively connected with the positive electrode and the negative electrode of an external power supply, two ends of the SMA alloy wire 8 are both fixed on the base 1, the shaft bushing 4 is arranged in a gap between the ball bushing 10 and the outer cover 3, a second groove for accommodating the upper limiting ball 13 is arranged at the upper part of the inner side wall of the shaft bushing 4, a third groove 17 for accommodating the lower limiting ball 5 is arranged in the middle of the inner side wall of the shaft bushing 4, the recovery spring 2 is sleeved on the outer side wall of the shaft bushing 4, the upper end of the recovery spring 2 abuts against the shaft bushing 4, and the lower end of;

the inner side of the split nut 7 is provided with a thread for connecting with a bolt 15, the outer side surface of the split nut 7 is provided with a fourth groove 18 for accommodating an upper limiting ball 13, the upper end of the split nut 7 is matched with a top cover 14 by a conical surface, the lower end of the split nut 7 is matched with the upper part of a top block 12 by a conical surface, and the inclined directions of the conical surfaces between the top block 12, the top cover 14 and the split nut 7 are suitable for promoting the split nut 7 to be separated;

the through hole is matched with the first groove 16 and the third groove 17, the second groove is matched with the fourth groove 18, the lower end of the bolt 15 is abutted against the ejector block 12, and the upper end of the bolt penetrates out of the top cover 14.

The driving block 6 is composed of two identical semi-cylindrical blocks, an SMA alloy wire accommodating groove 19 is formed in the rectangular surface of each semi-cylindrical block, a half first groove 16 is formed in the cylindrical surface of each semi-cylindrical block, and the two semi-cylindrical blocks are attached together to form a complete first groove 16. The SMA alloy wire 8 is firstly placed in the SMA alloy wire accommodating groove 19 in one of the semi-cylindrical blocks, then the two semi-cylindrical blocks are combined together and adhered together by using glue, so that the two semi-cylindrical blocks form a driving block 6, the SMA alloy wire 8 is stretched and lengthened under the action of the tension of the lower compression spring 9 at low temperature, the deformation is 5% -8%, the deformation length meets the driving displacement, and at the moment, two ends of the SMA alloy wire 8 are required to be fixed on the base 1. When the temperature of the material exceeds the austenite phase change temperature, the restoring force of the SMA alloy wire 8 is larger than the pulling force of the lower compression spring 9, the SMA alloy wire 8 can be completely contracted to the original length, and the contraction displacement is the driving displacement, so that the unlocking requirement is met.

The SMA alloy wire 8 is divided into an arc shape in the SMA alloy wire accommodating groove 19, so that the output displacement can be increased, the rest part is in a linear state, a linear driving mode and the optimized depth of the ball sleeve are adopted, the driving displacement and the driving force of the SMA alloy wire 8 can be ensured, and the unlocking time is greatly reduced.

Through-hole on the ball cover 10 evenly sets up a plurality ofly, and all has one down spacing ball 5 in each through-hole, because down spacing ball 5 installs in ball cover 10, and ball cover 10 exerts axial restraint to it, has guaranteed the synchronism of the 5 axial movements of a plurality of balls down, and this structure can improve the unblock precision greatly.

First recess 16, second recess, third recess 17 and fourth recess 18 are the ring channel, and the notch size of ring channel is wider than the tank bottom size setting, do benefit to the business turn over of spacing ball 5 and last spacing ball 13 in the ring channel down, and the unblock time that significantly reduces.

The top of the ejector block 12 is provided with a plane which is abutted against the bolt 15, and the outer surface of the shaft bushing 4 is provided with a restoring spring 2 for abutting against the platform.

The split nut 7 is 3 or 4, the split nut 7 consisting of three or four split parts is matched with the bolt 15, and the threads between the split nut 7 and the bolt can effectively disperse pretightening force, so that unlocking is facilitated.

The unlocking device is made of light alloy materials.

The base 1 is provided with a ceramic insulating layer.

The split nuts 7 are connected through springs, when the split nuts 7 are kept in a folded state, the springs between the adjacent lobes are in a compressed state, and the radial separation of the split nuts 7 is promoted through the restoring force of the springs.

The working process of the space unlocking device driven by the SMA wire comprises the following steps:

in a locking state, namely an SMA alloy wire 8 is in a non-energized state, the driving block 6 is positioned at the upper part inside the ball sleeve 10 under the support of the lower compression spring 9, the first groove 16 on the driving block 6 is higher than the through hole on the ball sleeve 10, the through hole of the ball sleeve 10 is communicated with the third groove 17 in the middle of the inner side wall of the bushing 4, the lower limiting ball 5 is arranged in the through hole and the third groove 17, the bushing 4 is acted by the restoring force of the restoring spring 2, radial force acts on the lower limiting ball 5 in the third groove 17, the lower limiting ball 5 is radially constrained by the driving block 6, the radial movement of the lower limiting ball 5 is limited, the lower limiting ball 5 has axial constraint force on the bushing 4, the axial movement of the bushing 4 is limited, the upper limiting ball 13 is arranged in the second groove at the upper part of the inner side wall of the bushing 4, and the bushing 4 applies radial force to the upper limiting ball 13, the split nuts 7 are radially constrained to keep the split nuts 7 closed;

in an unlocking state, namely, the SMA alloy wire 8 is electrified to be subjected to phase change and contract, the driving block 6 moves downwards, the lower compression spring 9 is compressed, when the first groove 16 on the driving block 6 moves downwards and is communicated with the through hole on the ball sleeve 10, the lower limiting ball 5 enters the first groove 16, the axial constraint force on the bushing 4 is relieved, the bushing 4 moves upwards to drive the upper limiting ball 13 to enter the fourth groove 18 on the split nut 7, the radial constraint on the split nut 7 is relieved, the split nut 7 is radially separated under the action of the top block 12, the upper compression spring 11 exerts axial pressure on the top block 12 and the bolt 15, the bolt 15 is ejected by the top block 12, and the unlocking is completed at the moment.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.