Keyway type limiting push pin device triggered by memory alloy wire

Abstract

The application provides a key groove type limiting push pin device triggered by a memory alloy wire and belongs to the technical field of key groove type limiting push pin devices. The device solves the problems of poor push pin structure stability, high operation risk and non-reusable property. The device comprises a cover, a push pin, a supporting barrel, a base, a rotating sleeve, a memory alloy wire, a tension spring, a driving compression spring and a stepped shaft. A first limiting groove matched with the push pin is arranged in the middle of the bottom of the base. A first shaft sleeve is arranged on the top of the base. The first shaft sleeve and the groove bottom of the first limiting groove are communicated. The lower end of the stepped shaft is arranged in the first shaft sleeve. The push pin is connected with the bottom end of the stepped shaft. The stepped shaft drives the push pin to move along the central axis direction of the stepped shaft. A rotating rod is rotatably arranged on the upper surface of the base. A limiting puller is arranged on one end of the rotating rod. The rotating sleeve is sleeved on the first shaft sleeve. The device is mainly used for aviation equipment.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of key groove type limiting push pin devices, and particularly relates to a key groove type limiting push pin device triggered by a memory alloy wire. BACKGROUND

[0002] Aviation equipment such as aircraft, rockets and satellites has a touch switch on the outer surface for convenient adjustment, but it is difficult for the driving operator to be outside the cabin for a long time, and there is great danger in the operation process, which threatens life and property safety. The push pin structure can be controlled to open the touch switch without human contact, but the operation process of the traditional push pin structure has a delay, especially in a low-oxygen high-pressure or oxygen-free environment, the push pin structure is prone to failure, which affects the operation of the operator. The delay time is too long or invalid, which may threaten the driving operator. In order to ensure the operation stability of the push pin structure, a high-strength and expensive metal material is often selected, but the push pin structure is mostly a disposable structure, which causes serious waste of resources. SUMMARY

[0003] Therefore, the application aims to provide a key groove type limiting push pin device triggered by a memory alloy wire to solve the problems of poor stability, high operation risk and non-reusable of the existing push pin structure.

[0004] In order to achieve the above object, the application adopts the following technical scheme: a key groove type limiting pushpin device triggered by a memory alloy wire, which comprises a top cover, a pushpin, a supporting cylinder, a base, a rotating sleeve, a memory alloy wire, a tension spring, a driving compression spring and a stepped shaft, a first limiting groove matched with the pushpin is formed in the middle of the bottom of the base, a first shaft sleeve is arranged on the top of the base, the first shaft sleeve and the groove bottom of the first limiting groove are communicated, the lower end of the stepped shaft is arranged in the first shaft sleeve, the pushpin is connected with the bottom end of the stepped shaft, the stepped shaft drives the pushpin to move along the central axis direction of the stepped shaft, a rotating rod is rotatably arranged on the upper surface of the base, a limiting tab is arranged on one end of the rotating rod, the rotating sleeve is sleeved on the first shaft sleeve, a second limiting groove matched with the limiting tab is formed in the bottom of one side of the rotating sleeve, an alloy wire fixing seat is arranged on the upper surface of the base, one end of the memory alloy wire is connected with the alloy wire fixing seat, the other end is connected with the rotating rod, the memory alloy wire drives the rotating rod to rotate, the lower end cover of the supporting cylinder is connected with the upper surface of the base, the upper end cover is arranged above the rotating sleeve, a through hole matched with the stepped shaft is arranged in the middle of the supporting cylinder, two grooves are symmetrically arranged on the top of the rotating sleeve, a sheet-shaped thrust needle bearing is arranged in each of the two grooves, fourth shaft portions are symmetrically arranged on both sides of the middle of the stepped shaft, the lower surface of the fourth shaft portion is in contact with the upper surface of the sheet-shaped thrust needle bearing, two first tension spring fixing columns are symmetrically arranged on the upper surface of the rotating sleeve, two second tension spring fixing columns are symmetrically arranged on the upper surface of the supporting cylinder, the first tension spring fixing columns and the second tension spring fixing columns are arranged one by one, the first tension spring fixing columns and the second tension spring fixing columns are connected through the tension spring, the tension spring drives the rotating sleeve to rotate, a third limiting groove matched with the fourth shaft portion is arranged on one side of each of the two grooves, a protrusion in contact with the fourth shaft portion is arranged on the other side of each of the two grooves, the lower end of the top cover is connected with the upper end cover of the supporting cylinder, a top plate is arranged on the top end of the top cover, a fourth limiting groove is arranged on the lower surface of the top plate, the driving compression spring is arranged in the fourth limiting groove, one end of the driving compression spring is connected with the lower surface of the top plate, the other end is connected with the top of the stepped shaft, the driving compression spring drives the stepped shaft to move along the central axis direction of the stepped shaft.

[0005] Furthermore, two arc-shaped holes are symmetrically arranged on the base, two adjusting end portions are symmetrically arranged on the outside of the bottom of the rotating sleeve, the two adjusting end portions correspond to the two arc-shaped holes one by one, and the bottom of the adjusting end portion is in sliding fit with the arc-shaped hole.

[0006] Furthermore, a rubber plug is arranged on the bottom of the arc-shaped hole.

[0007] Further, the stepped shaft comprises coaxially arranged first, second, third and fifth shaft parts, the first, second, third and fifth shaft parts are sequentially connected from top to bottom, the two fourth shaft parts are symmetrically arranged on the two sides of the third shaft part, the outer edge of the second shaft part is provided with a plurality of limiting flaps at equal intervals, the plurality of limiting flaps are all arranged on the lower end of the outer edge of the fourth limiting groove in the axial direction of the central axis of the stepped shaft, the driving compression spring is sleeved on the first shaft part, the bottom end of the driving compression spring sleeve abuts against the second shaft part, and the fifth shaft part is connected with the push pin.

[0008] Further, the deep groove ball bearing is arranged between the rotating sleeve and the first shaft sleeve, and the rotating sleeve is rotationally connected with the first shaft sleeve through the deep groove ball bearing.

[0009] Further, the push pin and the fifth shaft part are connected through the fastening nut.

[0010] Further, the upper surface of the base is provided with a plurality of guide wheels, the memory alloy wire is wound on the plurality of guide wheels, the upper surface of the base is provided with a wire slot for accessing the cable, the cable and the memory alloy wire are connected, the memory alloy wire is powered through the cable, and the memory alloy wire shrinks along the guide path of the plurality of guide wheels to drive the rotating rod to rotate around the center line.

[0011] Further, the upper cover and the supporting barrel are connected through a plurality of positioning screws, and the supporting barrel and the base are connected through a plurality of fastening screws.

[0012] Further, the upper surface of the base is provided with a rotating rod fixing shaft and a plurality of guide wheel fixing shafts, the rotating rod is rotationally connected to the upper surface of the base through the rotating rod fixing shaft, and the plurality of guide wheels are all rotationally connected to the upper surface of the base through the guide wheel fixing shafts.

[0013] Further, the alloy wire fixing seat and the rotating rod are connected through the limiting torsion spring, one end of the limiting torsion spring is connected with the alloy wire fixing seat, and the other end is connected with the limiting tab of the rotating rod.

[0014] Compared with the prior art, the beneficial effects of the present application are:

[0015] 1. The key groove type limiting push pin device can be used in the working area which cannot be manually touched or cannot be touched for a long time by the human body, such as an external button which needs to be actively pressed in space, or a button located on the outside of a spacecraft, and is also suitable for other positions which cannot be stayed for a long time by the human body, such as a narrow gap.

[0016] 2. The key groove type limiting push pin device can be reset and can be repeatedly used.

[0017] 3、The present application has simple structure, weakens external intervention factors, and reduces extra risks generated during use;

[0018] 4、The present application adopts a shape memory alloy wire acting structure primary drive source, improves product reusability, and greatly reduces use cost;

[0019] 5、The present application greatly reduces structure size use condition, and widens structure applicability field;

[0020] 6、The key groove type limiting push pin device in the present application is driven by electric current, and the shape memory alloy wire shrinks after being electrified, has high sensitivity, stable working state, and rapid response, and completes the push pin work at the same time of electrification. BRIEF DESCRIPTION OF DRAWINGS

[0021] The drawings constituting a part of the present application are used to provide further understanding of the present application, the illustrative embodiments of the present application and the description thereof are used to explain the present application, and do not constitute improper limitation on the present application. In the drawings:

[0022] Figure 1 It is a structure schematic view of the key groove type limiting push pin device triggered by the shape memory alloy wire according to the present application;

[0023] Figure 2 It is a front view sectional view of the key groove type limiting push pin device triggered by the shape memory alloy wire according to the present application;

[0024] Figure 3 It is a structure schematic view of the upper surface of the base of the key groove type limiting push pin device triggered by the shape memory alloy wire according to the present application;

[0025] Figure 4 It is a structure schematic view of the stepped shaft of the key groove type limiting push pin device triggered by the shape memory alloy wire according to the present application;

[0026] Figure 5 It is a structure schematic view of the upper cover of the key groove type limiting push pin device triggered by the shape memory alloy wire according to the present application;

[0027] Figure 6 It is a structure schematic view of the base of the key groove type limiting push pin device triggered by the shape memory alloy wire according to the present application;

[0028] Figure 7 It is a structure schematic view of the connection between the supporting cylinder and the upper cover of the key groove type limiting push pin device triggered by the shape memory alloy wire according to the present application;

[0029] Figure 8 It is a structure schematic view of the connection between the supporting cylinder and the base of the key groove type limiting push pin device triggered by the shape memory alloy wire according to the present application;

[0030] Figure 9 Structure diagram of the bottom surface of the base of the keyway type limiting push pin device triggered by a memory alloy wire.

[0031] 1-upper cover, 2-holding cylinder, 3-base, 4-step shaft, 5-driving compression spring, 6-tension spring, 7-first tension spring fixing column, 8-plate-shaped thrust needle bearing, 9-rotary sleeve, 10-deep groove ball bearing, 11-limiting torsion spring, 12-rotary rod, 13-rotary rod fixing shaft, 14-alloy wire fixing seat, 15-guide wheel, 16-guide wheel fixing shaft, 17-push pin, 18-fastening nut, 19-rubber plug, 20-memory alloy wire, 21-cable, 22-positioning screw, 23-fastening screw, 24-groove, 25-protrusion, 26-second tension spring fixing column, 301-first limiting groove, 302-first shaft sleeve, 401-first shaft part, 402-second shaft part, 403-third shaft part, 404-fourth shaft part, 405-fifth shaft part. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict, and the described embodiments are only a part of the embodiments of the present application, not all the embodiments.

[0033] Reference Figures 1-9The embodiment is illustrated as a key groove type limiting push pin device triggered by a memory alloy wire, which comprises an upper cover 1, a push pin 17, a supporting cylinder 2, a base 3, a rotating sleeve 9, a memory alloy wire 20, a tension spring 6, a driving compression spring 5 and a stepped shaft 4. A first limiting groove 301 is formed in the middle of the bottom of the base 3 and matched with the push pin 17. A first shaft sleeve 302 is arranged on the top of the base 3. The first shaft sleeve 302 is communicated with the groove bottom of the first limiting groove 301. The lower end of the stepped shaft 4 is arranged in the first shaft sleeve 302. The push pin 17 is connected with the bottom end of the stepped shaft 4. The stepped shaft 4 drives the push pin 17 to move along the central axis direction of the stepped shaft 4. A rotating rod 12 is arranged on the upper surface of the base 3 in a rotating mode. A limiting tab is arranged on one end of the rotating rod 12. The rotating sleeve 9 is sleeved on the first shaft sleeve 302. A second limiting groove is formed in the bottom of one side of the rotating sleeve 9 and matched with the limiting tab. An alloy wire fixing seat 14 is arranged on the upper surface of the base 3. One end of the memory alloy wire 20 is connected with the alloy wire fixing seat 14, and the other end is connected with the rotating rod 12. The memory alloy wire 20 drives the rotating rod 12 to rotate. The overall shape of the rotating rod 12 is “7”. The rotating rod 12 rotates when working. When the memory alloy wire 20 pulls the short end of the rotating rod 12, the long end of the rotating rod 12 will move away from the rotating sleeve 9 under the action of the lever, thereby releasing the limitation on the rotating sleeve 9. The limiting tab of the rotating rod 12 is used to limit the rotation of the rotating sleeve 9 around the central axis. The memory alloy wire 20 pulls the rotating rod 12 to rotate around the central axis and drives the limiting tab to move out of the second limiting groove.

[0034] The lower end cover of the supporting cylinder 2 is connected with the upper surface of the base 3, the upper end cover is arranged above the rotating sleeve 9, the middle part of the supporting cylinder 2 is provided with a through hole matched with the stepped shaft 4, the top of the rotating sleeve 9 is symmetrically provided with two grooves 24, the two grooves 24 are both provided with a sheet-shaped thrust needle bearing 8, the middle part of the stepped shaft 4 is symmetrically provided with a fourth shaft part 404 on both sides, the lower surface of the fourth shaft part 404 is in contact and cooperation with the upper surface of the sheet-shaped thrust needle bearing 8, the upper surface of the rotating sleeve 9 is symmetrically provided with two first tension spring fixing columns 7, the upper surface of the supporting cylinder 2 is symmetrically provided with two second tension spring fixing columns 26, the first tension spring fixing column 7 and the second tension spring fixing column 26 are arranged one by one, the first tension spring fixing column 7 and the second tension spring fixing column 26 are connected through a tension spring 6, the tension spring 6 drives the rotating sleeve 9 to rotate, one side of the two grooves 24 is provided with a third limiting groove matched with the fourth shaft part 404, and the other side is provided with a protrusion 25 in contact and cooperation with the fourth shaft part 404, when the two third limiting grooves of the rotating sleeve 9 are both rotated to be below the corresponding first limiting piece through the driving of the tension spring 6, the first limiting piece on the stepped shaft 4 is operable to slide in the corresponding third limiting groove along the central axis direction of the stepped shaft 4, the protrusion blocks the fourth shaft part 404 of the stepped shaft 4 to prevent the rotating sleeve 9 from rotating when sliding along the central axis direction of the stepped shaft 4, the lower end of the upper cover 1 is connected with the upper end cover of the supporting cylinder 2, the top end of the upper cover 1 is provided with a top plate, the lower surface of the top plate is provided with a fourth limiting groove, a driving compression spring 5 is arranged in the fourth limiting groove, one end of the driving compression spring 5 is connected with the lower surface of the top plate, and the other end is connected with the top of the stepped shaft 4, the driving compression spring 5 drives the stepped shaft 4 to move along the central axis direction of the stepped shaft 4, and the fourth shaft part 404 ensures that the driving compression spring 5 is in a compressed state and stores kinetic energy.

[0035] In the embodiment, two arc-shaped holes are symmetrically arranged on the base 3, two adjusting end parts are symmetrically arranged on the outer side of the bottom of the rotating sleeve 9, the two adjusting end parts correspond to the two arc-shaped holes one by one, the bottom of the adjusting end part is in sliding cooperation with the arc-shaped hole, and the position of the key groove type limiting push pin device is adjusted to reset through the rotating of the rotating sleeve 9 along the arc-shaped hole by pushing the push pin 17 along the central axis direction of the stepped shaft 4.

[0036] In the embodiment, the bottom of the arc-shaped hole is provided with a rubber plug 19, and the rubber plug 19 is detachably arranged in the arc-shaped hole.

[0037] The stepped shaft 4 in the embodiment comprises coaxially arranged first shaft part 401, second shaft part 402, third shaft part 403 and fifth shaft part 405, which are sequentially connected from top to bottom, the two fourth shaft parts 404 are symmetrically arranged on both sides of the third shaft part 403, the outer edge of the second shaft part 402 is provided with a plurality of limiting flaps at equal intervals, the plurality of limiting flaps are all slidingly arranged at the lower end of the outer edge of the fourth limiting groove along the central axis direction of the stepped shaft 4, the driving compression spring 5 is sleeved on the first shaft part 401, the bottom end of the driving compression spring 5 abuts against the second shaft part 402, the fifth shaft part 405 is connected with the push pin 17, wherein the first shaft part 401 plays a limiting role on the driving compression spring 5, the fifth shaft part 405 is a threaded structure and is cooperatively installed with a circular nut, and the character-shaped protrusion of the fifth shaft part 405 cooperates with the character-shaped groove of the push pin 17, the stepped shaft 4 is screwed into the circular nut in the push pin 17 so as to fix the push pin 17.

[0038] The deep groove ball bearing 10 is arranged between the rotating sleeve 9 and the first shaft sleeve 302 in the embodiment, the rotating sleeve 9 is rotatably connected with the first shaft sleeve 302 through the deep groove ball bearing 10, and the deep groove ball bearing 10 facilitates the rotation of the rotating sleeve 9.

[0039] The push pin 17 and the fifth shaft part 405 are connected through the fastening nut 18 in the embodiment.

[0040] The upper surface of the base 3 is provided with a plurality of guide wheels 15 in the embodiment, the memory alloy wire 20 is wound on the plurality of guide wheels 15, the upper surface of the base 3 is provided with a wire slot for accessing the cable 21, the cable 21 and the memory alloy wire 20 are connected, the memory alloy wire 20 is energized through the cable, and the memory alloy wire 20 shrinks along the guide path of the plurality of guide wheels 15 to drive the rotating rod 12 to rotate around the center line.

[0041] The upper cover 1 and the supporting barrel 2 are connected through a plurality of positioning screws 22 in the embodiment, the supporting barrel 2 and the base 3 are connected through a plurality of fastening screws 23, the upper cover 1 has an inner-outer layer structure, the inner layer has a fourth limiting groove, the fourth limiting groove of the upper cover 1 cooperates with the stepped shaft 4 through the driving compression spring 5, the outer layer has a plurality of notches and holes, which have the functions of positioning and fixing, and the positioning screws 22 pass through the holes and are fixed with the supporting barrel 2.

[0042] The alloy wire fixing seat 14 and the rotating rod 12 are connected through the limiting torsion spring 11 in the embodiment, one end of the limiting torsion spring 11 is connected with the alloy wire fixing seat 14, and the other end is connected with the limiting tab of the rotating rod 12, and the limiting torsion spring 11 is used for resetting the driving rotating rod 12 when the rotating sleeve 9 is reset.

[0043] In this embodiment, the memory alloy wire 20 is electrified, the memory alloy wire 20 is heated to start shrinking, under the guidance of the guide wheel 15, the one end of the rotating rod 12 is pulled, the rotating rod 12 rotates around the rotating point, the other end of the rotating rod 12 releases the constraint on the rotating sleeve 9, the inner wall of the rotating sleeve 9 contacts with the outer ring of the deep groove ball bearing 10, the rotating sleeve 9 can rotate in the supporting cylinder 2, the sheet-shaped thrust needle bearing 8 is placed in the rotating sleeve 9, when the rotating sleeve 9 rotates to a certain position, the stepped shaft 4 placed on the sheet-shaped thrust needle bearing 8 is released, under the thrust of the driving compression spring 5 inside the upper cover 1, the lock pin is ejected from the supporting cylinder 2, and the action is ended to realize the unlocking function.

[0044] In this embodiment, the first tension spring fixing column 7 is embedded on the upper end surface of the rotating sleeve 9, the second tension spring fixing column 26 is embedded in the supporting cylinder 2, the tension spring 6 is in an elongated state and connected between the first tension spring fixing column 7 on the rotating sleeve 9 and the second tension spring fixing column 26 on the supporting cylinder 2, wherein the supporting cylinder 2 and the second tension spring fixing column 26 on the supporting cylinder 2 are fixed in position, when the constraint of the rotating sleeve 9 is released, the tension spring 6 contracts, pulls the second tension spring fixing column 26 on the supporting cylinder 2 through the tension spring 6, and drives the first tension spring fixing column 7 to move, so as to make the rotating sleeve 9 rotate, the upper end of the rotating sleeve 9 is provided with a groove 24 and a protrusion 25, the groove 24 is used to place the sheet-shaped thrust needle bearing 8, and the protrusion 25 blocks the fourth shaft part 404 of the stepped shaft 4 to prevent it from rotating, the rotating sleeve 9 is internally fitted with the deep groove ball bearing 10, and the rotating action of the rotating sleeve 9 is realized.

[0045] In this embodiment, the upper end of the stepped shaft 4 is pressed by the driving compression spring 5, the driving compression spring 5 is embedded in the inside of the upper cover 1, the second shaft part 402 of the stepped shaft 4 slides on the outer edge lower end groove of the fourth limiting groove of the upper cover 1, the fourth shaft part 404 of the stepped shaft 4 is in initial contact with the sheet-shaped thrust needle bearing 8, the sheet-shaped thrust needle bearing 8 is placed in the groove 24 of the rotating sleeve 9, when the rotating sleeve 9 rotates, the sheet-shaped thrust needle bearing 8 in the groove 24 will rotate, after the rotating sleeve 9 rotates to a certain extent, the fourth shaft part 404 of the stepped shaft 4 will fall from the third limiting groove of the rotating sleeve 9 under the elastic force of the driving compression spring 5, the fifth shaft part 405 of the stepped shaft 4 is a threaded structure and is installed in cooperation with a circular nut, the push pin 17 is in the shape of a cuboid, and has a character-shaped groove and a circular groove inside, wherein the character-shaped groove cooperates with the character-shaped protrusion of the fifth shaft part 405 of the stepped shaft 4, and the circular groove is used to place the circular nut, the stepped shaft 4 is screwed into the circular nut in the push pin 17, so as to fix the push pin 17.

[0046] The working principle of this embodiment is as follows:

[0047] In the working process of the embodiment, the memory alloy wire 20 is electrified, the memory alloy wire 20 is contracted along the path arranged by the guide wheel 15, the rotating rod 12 is pulled, the limiting tab of the rotating rod 12 is moved out of the second limiting groove of the rotating sleeve 9, the rotating sleeve 9 is limited, the tension spring 6 is contracted and recovered, the rotating sleeve 9 is pulled to rotate around the central axis, when the rotating sleeve 9 rotates to a certain position, the fourth shaft part 404 of the stepped shaft 4 contacts the protrusion 25 on the rotating sleeve 9, the sheet-shaped thrust needle bearing 8 releases the limiting action on the fourth shaft part 404, the driving compression spring 5 releases the compressed state, the driving compression spring 5 is recovered, the fourth shaft part 404 of the stepped shaft 4 is moved out of the third limiting groove of the rotating sleeve 9, the driving compression spring 5 pushes the stepped shaft 4 to displace along the central axis, the fifth shaft part 405 is pushed out, the function of pushing the push pin 17 is realized, the device part which cannot be directly touched by the human body can be used, and the function of pressing the switch button is realized.

[0048] One end of the limiting torsion spring 11 is connected with the alloy wire fixing seat 14, and the other end of the limiting torsion spring 11 is connected with the limiting tab on the rotating rod 12, after the work of the key groove type limiting push pin device, the rotating rod 12 is in the state of being pulled out of the second limiting groove of the rotating sleeve 9 by the memory alloy wire 20, since the rotating sleeve 9 rotates under the pulling of the tension spring 6, the end of the rotating rod 12 abuts against the outer wall of the rotating sleeve 9, at this time, the limiting torsion spring 11 is in the compressed state, and the kinetic energy is stored.

[0049] The arc-shaped hole is arranged on the base 3, the fifth shaft part 405 of the stepped shaft 4 is pushed back into the base 3, the rotating sleeve 9 is pushed and rotated in the reverse direction by using a special reset tool or a strip-shaped tool which can pass through the arc-shaped hole, after the rotating sleeve 9 is reset, the kinetic energy of the limiting torsion spring 11 is released, the end of the rotating rod 12 is pushed into the second limiting groove of the rotating sleeve 9, the locking function is realized, and the reset of the key groove type limiting push pin device is realized.

[0050] The second shaft part 402 is used for abutting against the end of the driving compression spring 5, a plurality of limiting tabs are arranged on the outer periphery of the second shaft part 402 at equal intervals and are used for abutting against the fourth limiting groove of the upper cover 1, so that the first shaft part 401 is prevented from colliding with the top cover of the upper cover 1 during the reset process.

[0051] The sheet-shaped thrust needle bearing 8 is arranged in the groove 24 on the upper surface of the rotating sleeve 9, the diameter deviation of the needle of the sheet-shaped thrust needle bearing 8 is extremely small, the needle can bear the axial heavy load and the maximum load, the stress peak value is prevented, the needle is slightly contracted at both ends to change the linear contact between the raceway and the needle, the service life of the bearing is prolonged, the fourth shaft part 404 contacts the rotating sleeve 9 through the sheet-shaped thrust needle bearing 8, the abrasion between the fourth shaft part 404 and the rotating sleeve 9 is reduced, the frictional resistance is reduced, and the service life of the key groove type limiting push pin device is prolonged.

[0052] The key groove type limiting push pin device can be used in the working area which cannot be manually touched by human body or cannot be touched for a long time, such as the external button which needs to be actively pressed in space, or the button located on the outside of the space shuttle, and is also suitable for other positions which cannot be stayed for a long time, such as narrow gaps.

[0053] The key groove type limiting push pin device can be reset and can be repeatedly used.

[0054] The key groove type limiting push pin device has simple structure, weak external intervention factors and low additional risk in use.

[0055] The key groove type limiting push pin device adopts a shape memory alloy wire action structure primary drive source, improves the reusability of the product, and greatly reduces the use cost.

[0056] The key groove type limiting push pin device greatly reduces the use of structure size, and widens the application field of the structure.

[0057] The key groove type limiting push pin device is driven by electric current, and the shape memory alloy wire 20 is contracted after being electrified, has high sensitivity, stable working state and rapid response, and completes the push work at the same time of electrification.

[0058] The above disclosed embodiments of the application are only used to help explain the application. The embodiments do not describe all the details, and do not limit the application to the specific embodiments. According to the content of the specification, many modifications and changes can be made. The specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the application, so that the persons skilled in the art can well understand and utilize the application.

Claims

1. A keyway-type limiting and pushing device triggered by a shape memory alloy wire, characterized in that: It includes upper cover (1), push pin (17), support cylinder (2), base (3), rotating sleeve (9), memory alloy wire (20), tension spring (6), drive compression spring (5) and stepped shaft (4), the middle part of the bottom of the base (3) is provided with a first limiting groove (301) matched with the push pin (17), the top of the base (3) is provided with a first shaft sleeve (302), the first shaft sleeve (302) and the groove bottom of the first limiting groove (301) are communicated, the lower end of the stepped shaft (4) is arranged in the first shaft sleeve (302), the push pin (17) is connected with the bottom end of the stepped shaft (4), the stepped shaft (4) drives the push pin (17) to move along the central axis direction of the stepped shaft (4), the upper surface of the base (3) is rotatably provided with a rotating rod (12), one end of the rotating rod (12) is provided with a limiting tab, the rotating sleeve (9) is sleeved on the first shaft sleeve (302), the bottom of one side of the rotating sleeve (9) is provided with a second limiting groove matched with the limiting tab, the upper surface of the base (3) is provided with an alloy wire fixing seat (14), one end of the memory alloy wire (20) is connected with the alloy wire fixing seat (14), the other end is connected with the rotating rod (12), the memory alloy wire (20) drives the rotating rod (12) to rotate, the lower end cover of the support cylinder (2) is connected with the upper surface of the base (3), the upper end cover is arranged above the rotating sleeve (9), the middle part of the support cylinder (2) is provided with a through hole matched with the stepped shaft (4), the top of the rotating sleeve (9) is symmetrically provided with two grooves (24), the two grooves (24) are both provided with a sheet-shaped thrust needle bearing (8), the middle part of the both sides of the stepped shaft (4) is symmetrically provided with a fourth shaft part (404), the lower surface of the fourth shaft part (404) is in contact with the upper surface of the sheet-shaped thrust needle bearing (8), the upper surface of the rotating sleeve (9) is symmetrically provided with two first tension spring fixing columns (7), the upper surface of the support cylinder (2) is symmetrically provided with two second tension spring fixing columns (26), the first tension spring fixing column (7) and the second tension spring fixing column (26) are correspondingly arranged, the first tension spring fixing column (7) and the second tension spring fixing column (26) are connected through the tension spring (6), the tension spring (6) drives the rotating sleeve (9) to rotate, one side of the two grooves (24) is provided with a third limiting groove matched with the fourth shaft part (404), the other side is provided with a protrusion (25) in contact with the fourth shaft part (404), the lower end of the upper cover (1) is connected with the upper end cover of the support cylinder (2), the top end of the upper cover (1) is provided with a top plate, the lower surface of the top plate is provided with a fourth limiting groove, the drive compression spring (5) is arranged in the fourth limiting groove, one end of the drive compression spring (5) is connected with the lower surface of the top plate, the other end is connected with the top of the stepped shaft (4), the drive compression spring (5) drives the stepped shaft (4) to move along the central axis direction of the stepped shaft (4).

2. The keyway limit push pin device triggered by memory alloy wire according to claim 1, characterized in that: Two arc-shaped holes are symmetrically arranged on the base (3), two adjusting ends are symmetrically arranged on the outer side of the bottom of the rotating sleeve (9), the two adjusting ends correspond to the two arc-shaped holes one by one, and the bottom of the adjusting end is in sliding fit with the arc-shaped hole.

3. The keyway limit push pin device triggered by memory alloy wire according to claim 2, characterized in that: The bottom of the arc-shaped hole is provided with a rubber plug (19).

4. The keyway limit push pin device triggered by memory alloy wire according to claim 1, characterized in that: The stepped shaft (4) comprises coaxially arranged first, second, third and fifth shaft portions (401, 402, 403 and 405), the first, second, third and fifth shaft portions (401, 402, 403 and 405) are sequentially connected from top to bottom, the two fourth shaft portions (404) are symmetrically arranged on the two sides of the third shaft portion (403), a plurality of limiting flaps are equidistantly arranged on the outer edge of the second shaft portion (402), the plurality of limiting flaps are all arranged in sliding fit on the outer edge of the lower end of the fourth limiting groove in the direction of the central axis of the stepped shaft (4), the driving compression spring (5) is sleeved on the first shaft portion (401), the bottom end of the driving compression spring (5) abuts against the second shaft portion (402), and the fifth shaft portion (405) is connected with the push pin (17).

5. The keyway limit push pin device triggered by memory alloy wire according to claim 1, characterized in that: The rotating sleeve (9) and the first shaft sleeve (302) are connected through the deep groove ball bearing (10).

6. The keyway limit push pin device triggered by memory alloy wire according to claim 4, characterized in that: The push pin (17) and the fifth shaft portion (405) are connected through the fastening nut (18).

7. The keyway limit push pin device triggered by memory alloy wire according to claim 1, characterized in that: The upper surface of the base (3) is provided with a plurality of guide wheels (15), the memory alloy wire (20) is wound on the plurality of guide wheels (15), the upper surface of the base (3) is provided with a wire slot for accessing the cable (21), the cable (21) and the memory alloy wire (20) are connected, the memory alloy wire (20) is contracted along the guide path of the plurality of guide wheels (15) by being electrified through the cable, and the rotating rod (12) is driven to rotate around the center line.

8. The keyway limit push pin device triggered by memory alloy wire according to claim 1, characterized in that: The upper cover (1) and the supporting cylinder (2) are connected through a plurality of positioning screws (22), and the supporting cylinder (2) and the base (3) are connected through a plurality of fastening screws (23).

9. The keyway limit push pin device triggered by memory alloy wire according to claim 7, characterized in that: The upper surface of the base (3) is provided with a rotating rod fixing shaft (13) and a plurality of guide wheel fixing shafts (16), the rotating rod (12) is rotatably connected to the upper surface of the base (3) through the rotating rod fixing shaft (13), and the plurality of guide wheels (15) are all rotatably connected to the upper surface of the base (3) through the guide wheel fixing shafts (16).

10. The memory alloy wire triggered keyway limit pushpin device of claim 1, wherein: The alloy wire fixing seat (14) and the rotating rod (12) are connected through the limiting torsional spring (11), one end of the limiting torsional spring (11) is connected with the alloy wire fixing seat (14), and the other end is connected with the limiting pushing piece of the rotating rod (12).

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