Locking and releasing mechanism with pressing and releasing triggered by SMA and test platform

Abstract

The invention discloses a locking and releasing mechanism with compaction and releasing triggered by SMA and a test platform. The locking and releasing mechanism comprises an installation platform, a to-be-locked piece, a locking unit, a locking power unit and a releasing power unit. Two supporting seats which are oppositely arranged are arranged on the mounting platform so as to realize the mounting of each unit; the to-be-locked piece is arranged between the two supporting seats; the locking unit comprises a pressing block, a reset spring and a wedge block. The pressing block can move towards and away from the top of the to-be-locked piece, and the pressing block abuts against the inclined plane part of the wedge block in an attached mode; the reset spring is used for pushing the pressing block to move towards the wedge block. The wedge block is clamped between the supporting seat and the pressing block and can transversely move towards and away from the to-be-locked piece; the locking power unit is used for controlling the wedge block to push the pressing block to press the piece to be locked; the power releasing unit is used for releasing the pressing block from pressing the to-be-locked piece; according to the scheme, the problems that an existing pressing and releasing mechanism is complex, the space utilization rate is low, impact is large and uncontrollable, and a narrow space driving source is difficult to arrange can be solved.

Description

Technical Field

[0001] This invention relates to the technical field of locking structures, and in particular to a locking and releasing mechanism and testing platform in which both clamping and releasing are triggered by SMA. Background Technology

[0002] Due to the need for free levitation, a certain gap exists between the stator and rotor of a magnetic levitation flywheel. During the launch phase, a locking mechanism is required to eliminate this gap, and the gap is released during the on-orbit phase.

[0003] Currently, there are three main types of locking mechanism drives both domestically and internationally: pyrotechnic drive, motor drive, and electromagnetic drive. The traditional locking release mechanism is a pyrotechnic pin puller, which uses the explosion of a pyrotechnic device to shear the locking pin, thus unlocking the mechanism. However, the explosion of a pyrotechnic device generates significant impact, adversely affecting satellite attitude control and precision optoelectronic equipment; furthermore, the gunpowder from the explosion contaminates the fiber optic system; and additionally, the pyrotechnic pin puller is a disposable device and cannot be reused. Motor and electromagnetic actuator control mechanisms are also a common approach to solving locking and levitation issues; however, they suffer from large system size, complex mechanisms, low reliability, and high power consumption. Therefore, as magnetic levitation flywheels become further miniaturized, the large size of these three drive mechanisms will severely limit their application in smaller flywheels. Summary of the Invention

[0004] The purpose of this invention is to provide a locking and releasing mechanism and a testing platform in which both clamping and releasing are triggered by SMA, so as to solve the problems of complex clamping and releasing mechanisms, low space utilization, large and uncontrollable impact of clamping and releasing mechanisms, and difficulty in laying out the driving source in narrow spaces in the prior art.

[0005] To solve the above-mentioned technical problems, the present invention provides a locking and releasing mechanism triggered by SMA for both clamping and releasing, including an installation platform, a component to be locked, a locking unit, a locking power unit, and a releasing power unit; the installation platform is provided with two oppositely arranged support seats, each of which is provided with the locking unit, the locking power unit, and the releasing power unit; the component to be locked is disposed between the two support seats; the locking unit includes a pressure block, a return spring, and a wedge; the pressure block is a structure that can move towards and away from the top of the component to be locked, and the pressure block has a force-receiving inclined surface away from the top surface of the component to be locked, the force-receiving inclined surface abutting against the inclined surface of the wedge; the return spring is used to push the pressure block towards the wedge; the wedge is clamped in place. Between the support base and the pressure block, the wedge is movable toward and away from the member to be locked, and the moving direction of the wedge is perpendicular to the moving direction of the pressure block; there are multiple locking power units, each including a locking SMA wire connected to the wedge, the deformation of the locking SMA wire after being energized is used to pull the wedge toward the member to be locked, so as to control the wedge to push the pressure block to press the member to be locked; there are multiple releasing power units, each including a releasing SMA wire connected to the wedge, the deformation of the releasing SMA wire after being energized is used to pull the wedge away from the member to be locked, so as to release the pressure block from the member to be locked.

[0006] In one embodiment, a guide ramp is provided at the top of the locking member and adjacent to the two support seats; a force-applying ramp is provided at the part of the two pressure blocks opposite to the two guide ramps, and the two force-applying ramps respectively fit and abut against the two guide ramps.

[0007] In one embodiment, the support base has a cavity on the surface facing the locking member, and a guide pin is provided in the cavity. The guide pin passes through the part of the pressure block placed in the cavity. The return spring is sleeved on the outside of the guide pin, and the return spring elastically abuts against the part of the pressure block placed in the cavity.

[0008] In one embodiment, the pressure block is provided with a guide wheel on the surface opposite to the component to be locked; the support base is provided with a guide rail, and the guide wheel is slidably mounted on the guide rail.

[0009] In one embodiment, the top of the support base is provided with a top beam; the wedge is clamped between the top beam and the pressure block, and the two opposite sides of the top surface of the wedge are provided with limiting protrusions, which respectively abut against the opposite sides of the top beam.

[0010] In one embodiment, the locking power unit further includes a locking conductive clamp and a locking insulated reversing wheel; one locking conductive clamp is disposed on the side of the support base away from the part to be locked, and the other locking conductive clamp is disposed on the wedge block; the locking insulated reversing wheel is disposed on the top beam; the locking SMA wire passes around the locking insulated reversing wheel, and the two ends of the locking SMA wire are respectively clamped and fixed on the two locking conductive clamps, and the locking SMA wire has a working state of being energized and contracted.

[0011] In one embodiment, the locking conductive clamp includes a locking conductive clip, a locking insulating block, a locking pressure plate, and a locking adjusting bolt; the locking conductive clip is clamped within the locking insulating block, and the locking conductive clip also clamps the locking SMA wire; the locking adjusting bolt passes sequentially through the locking pressure plate and the locking insulating block, and tightening the locking adjusting bolt is used to press the locking pressure plate against the locking conductive clip.

[0012] In one embodiment, the release power unit further includes a release conductive clamp and a release insulating reversing wheel; one of the release conductive clamps is disposed on the top beam, and the other of the release conductive clamp is disposed on the wedge block; the release insulating reversing wheel is disposed on the side of the support base away from the locking member; the release SMA wire passes around the release insulating reversing wheel, and the two ends of the release SMA wire are respectively clamped and fixed on the two release conductive clamps, and the release SMA wire has an energized retractable working state.

[0013] In one embodiment, the release conductive clamp includes a release conductive clip, a release insulating block, a release pressure plate, and a release adjusting bolt; the release conductive clip is clamped within the release insulating block, and the release conductive clip holds the release SMA wire; the release adjusting bolt passes sequentially through the release pressure plate and the release insulating block, and tightening the release adjusting bolt is used to press the release pressure plate against the release conductive clip.

[0014] To address the aforementioned technical problems, the present invention also provides a testing platform, including the aforementioned locking and releasing mechanism. The mounting platform is equipped with an coded mounting base, on which a displacement encoder is mounted. A synchronously rotating pulley is connected to the signal acquisition point of the displacement encoder. A connecting rope is wound around the pulley, with one end of the connecting rope connected to the wedge block and the other end connected to a pre-tightening weight. Furthermore, a force sensor is located at the bottom of the component to be locked, mounted on the mounting platform, and is used to detect the pressure exerted on the component to be locked.

[0015] The beneficial effects of this invention are as follows: 1. Both clamping and releasing are driven by SMA, making it suitable for various complex and narrow drive source spaces. SMA is a filamentous structure, and both the drive and release are made of SMA wire. Compared with spring release, it can be used in narrower working environments. 2. Compact structure, suitable for small locking applications. Both the tightening and releasing of the SMA wires act on the self-locking wedge and the vertical mounting base, making full use of the space of the drive source; 3. The impact of locking and unlocking can be controlled. Both the drive and release are applied by SMA wires. By controlling the magnitude of the applied current, the impact during locking and unlocking can be reduced. 4. One pre-tightening installation allows for repeated testing; no pollution. The device has no disposable consumables and can be repeatedly compressed and released after the initial pre-tightening installation without the need for manual rearrangement. The device does not produce any excess material or pollution such as exhaust gas in either the compressed or released state. 5. Features a safety design with a high tolerance for compression and release errors. When multiple SMA filaments work together, if one set of SMA filaments malfunctions, the remaining SMA filaments can still achieve compression and release. Attached Figure Description

[0016] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the locking and releasing mechanism provided in an embodiment of the present invention; Figure 2 yes Figure 1 A schematic diagram of the cross-sectional structure; Figure 3 yes Figure 2 A schematic diagram of the structure of the component to be locked; Figure 4 yes Figure 2 A schematic diagram of the briquetting block structure; Figure 5 This is a schematic diagram of the guide wheel assembly method provided in an embodiment of the present invention; Figure 6 yes Figure 1 A partially enlarged structural diagram; Figure 7 yes Figure 1 A magnified diagram from a top-down perspective; Figure 8 yes Figure 7 A schematic diagram of the conductive clamp structure for locking; Figure 9 yes Figure 7 A schematic diagram of the conductive clip structure for release; Figure 10 This is a schematic diagram of the force analysis principle provided in an embodiment of the present invention; Figure 11 This is a schematic diagram of the test platform structure provided in an embodiment of the present invention.

[0018] The attached figures are labeled as follows: 100. Installation platform; 110. Support base; 111. Cavity; 112. Guide rail; 113. Top beam; 200. Component to be locked; 210. Guide ramp; 300 Locking unit; 310 Pressure block; 311 Force-receiving inclined surface; 312 Force-applying inclined surface; 320 Return spring; 330 Wedge block; 331 Limiting protrusion; 340 Guide pin; 350 Guide wheel; 400. Locking power unit; 410. Locking SMA wire; 420. Locking conductive clamp; 421. Locking conductive clamp plate; 422. Locking insulating clamp block; 423. Locking pressure plate; 424. Locking adjusting bolt; 430. Locking insulating reversing wheel; 500. Release power unit; 510. SMA wire for release; 520. Conductive clamp for release; 521. Conductive clamp plate for release; 522. Insulating clamp block for release; 523. Pressure plate for release; 524. Adjusting bolt for release; 530. Insulating reversing wheel for release; 610. Encoder mounting base; 620. Displacement encoder; 630. Pulley; 640. Connecting rope; 650. Preload weight; 660. Force sensor. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0020] This invention provides a locking and releasing mechanism in which both clamping and releasing are triggered by an SMA, such as... Figure 1 As shown, this embodiment sets the locking and releasing mechanism to include an installation platform 100, a locking component 200, a locking unit 300, a locking power unit 400, and a releasing power unit 500.

[0021] Regarding the installation platform 100, as Figure 1As shown, in this embodiment, the installation platform 100 is provided with two oppositely arranged support seats 110, and each support seat 110 is provided with a locking unit 300, a locking power unit 400, and a releasing power unit 500.

[0022] Obviously, the design rationality of the support base 110, as the load-bearing structure of each unit, will have a significant impact on the structural compactness of the locking and releasing mechanism. Therefore, in order to improve space utilization, such as Figure 1 As shown, in this embodiment, the support base 110 is arranged vertically on the mounting platform 100. At this time, the bottom of the support base 110 is connected and fixed to the mounting platform 100, the middle part of the support base 110 is used to install the locking unit 300, and the top of the support base 110 is used to install the locking power unit 400 and the releasing power unit 500. This makes full use of the longitudinal space of the support base 110, so that multiple units can be compactly installed on the support base 110.

[0023] Regarding the locking member 200, as... Figure 1 As shown, in this embodiment, the locking element 200 is positioned between the two support seats 110. At this time, the locking element 200 is the target of the locking and releasing mechanism, and its locking is achieved by the locking unit 300 applying pressure to it.

[0024] It should be noted that although the diagram shows the component to be locked 200 positioned on the mounting platform 100, this illustration is for illustrative purposes only and does not represent the actual installation method of the component to be locked 200. For example, after the locking and releasing mechanism is installed and applied, if the locking unit 300 has already locked and positioned the component to be locked 200, the component to be locked 200 will be fixed in a designated position. If the locking unit 300 releases the lock on the component to be locked 200, a corresponding magnetic levitation mechanism will control the component to be locked 200 to levitate. Figure 1 The content shown is for illustrative purposes only and is intended to simplify the structure.

[0025] Regarding the locking unit 300, as Figures 1 to 4 As shown, in this embodiment, the locking unit 300 includes a pressure block 310, a return spring 320, and a wedge 330. The pressure block 310 is movable toward and away from the top of the member to be locked 200. The pressure block 310 has a force-bearing inclined surface 311 on the side away from the top surface of the member to be locked 200. The force-bearing inclined surface 311 abuts against the inclined surface of the wedge 330. The return spring 320 is used to push the pressure block 310 toward the wedge 330. The wedge 330 is clamped between the support base 110 and the pressure block 310. The wedge 330 is movable toward and away from the member to be locked 200. The moving direction of the wedge 330 is perpendicular to the moving direction of the pressure block 310.

[0026] After adopting the above setting method, if the locking unit 300 is not subjected to any external driving force, the return spring 320 will apply an upward pushing force to the pressure block 310, releasing the pressure block 310 from pressing the locking member 200, thereby making the locking member 200 in an unlocked state.

[0027] If an external driving force controls the wedges 330 on both sides of the locking member 200 to move towards each other, the wedges 330 will apply a downward pushing force to the pressing block 310, and the pressing block 310 will press the locking member 200, thereby making the locking member 200 locked.

[0028] Similarly, if an external driving force controls the wedges 330 on both sides of the locking member 200 to move apart, the thrust exerted by the wedges 330 on the pressure block 310 will be weakened, and the pressure block 310 will release the pressure on the locking member 200, thereby making the locking member 200 become unlocked.

[0029] In order to ensure that the pressure block 310 can apply stable and precise pressure to the locking component 200, such as Figure 2 and Figure 3 As shown, in this embodiment, guide ramps 210 are provided at the top of the locking member 200 and adjacent to the two support seats 110. Figure 2 In the indicated directions, the left guide ramp 210 is positioned facing upwards to the left, and the right guide ramp 210 is positioned facing upwards to the right; both pressure blocks 310 and the parts opposite to the two guide ramps 210 are provided with force-applying inclined surfaces 312. Figure 2 In the direction shown, the left force-applying inclined surface 312 is set facing downward to the right, and the right force-applying inclined surface 312 is set facing downward to the left, so that the two force-applying inclined surfaces 312 can respectively fit and abut against the two guide slopes 210.

[0030] In addition, in order to achieve the purpose of moving the pressure block 310 toward and away from the top of the locking member 200, this embodiment is provided with the pressure block 310 being able to... Figure 2 The support 110 moves vertically in the direction shown. At this time, the surface of the support 110 facing the locking part 200 has a cavity 111. A guide pin 340 is provided in the cavity 111. The guide pin 340 is vertically arranged and passes through the part of the pressure block 310 placed in the cavity 111. The return spring 320 is sleeved on the outside of the guide pin 340. The top of the return spring 320 abuts against the bottom surface of the part of the pressure block 310 placed in the cavity 111, and the bottom surface of the return spring 320 abuts against the inner bottom surface of the cavity 111. This allows the return spring 320 to form an elastic abutment with the part of the pressure block 310 placed in the cavity 111, thereby ensuring that the pressure block 310 always maintains the tendency to move away from the locking part 200 when not driven by external force.

[0031] Furthermore, to ensure the smooth movement of the pressing block 310 and to restrict the movement path of the pressing block 310, such as Figure 5 As shown, in this embodiment, the pressure block 310 is provided with a guide wheel 350 on the surface opposite to the locking member 200. The guide wheel 350 is a concave wheel with a recessed surface forming an annular groove. The two guide wheels 350 are respectively arranged on opposite sides of the pressure block 310, and the rotation axis of the two guide wheels 350 is perpendicular to the surface of the pressure block 310. The support base 110 is provided with a guide rail 112. The two guide rails 112 are respectively located on the outside of the two guide wheels 350. The two guide rails 112 are both straight strip structures. The two guide rails 112 are respectively embedded in the annular groove of the two guide wheels 350, thereby achieving the purpose of slidingly mounting the guide wheel 350 on the guide rail 112.

[0032] After adopting the above configuration, the cooperation between the guide rail 112 and the guide wheel 350 will restrict the pressure block 310 to move back and forth in a straight line in a specific direction. The relative sliding installation of the guide rail 112 and the guide wheel 350 will also ensure that the pressure block 310 can move more smoothly.

[0033] It should also be noted that the wedge 330 is held between the support base 110 and the pressure block 310, and is also capable of lateral reciprocating movement. Therefore, to prevent the wedge 330 from shifting during movement, such as Figure 6 As shown, in this embodiment, the top of the support base 110 is provided with a top beam 113. The top beam 113, wedge 330 and pressure block 310 are arranged in sequence from top to bottom. The wedge 330 is clamped between the top beam 113 and the pressure block 310. The two opposite sides of the top surface of the wedge 330 are provided with limiting protrusions 331. The two limiting protrusions 331 abut against the opposite sides of the top beam 113, thereby restricting the movement direction of the wedge 330 and preventing the wedge 330 from deviating during movement.

[0034] Regarding the aforementioned locking power unit 400, such as Figure 1 and Figure 7 As shown, this embodiment sets multiple locking power units 400. Each locking power unit 400 includes a locking SMA wire 410, which is connected to a wedge block 330. The deformation of the locking SMA wire 410 after being energized is used to pull the wedge block 330 to move toward the member to be locked 200, so as to control the wedge block 330 to push the pressure block 310 to press the member to be locked 200.

[0035] At this time, the locking power unit 400 is mainly used to control the on and off of the locking SMA wire 410. Since the locking SMA wire 410 is a shape memory alloy, shape memory alloys will produce different deformations under different on and off states. Length deformation is a common change mode of shape memory alloys. Therefore, by using the locking power unit 400 to control the on and off state of the locking SMA wire 410, the length of the locking SMA wire 410 can be controlled, thereby achieving the purpose of pulling the wedge block 330 in a specific direction by the locking SMA wire 410.

[0036] Furthermore, in order to reduce the space occupied by the locking power unit 400, such as Figure 1 and Figure 7 As shown, this embodiment of the locking power unit 400 also includes a locking conductive clamp 420 and a locking insulated reversing wheel 430; one locking conductive clamp 420 is located on the side of the support base 110 away from the part to be locked 200, and another locking conductive clamp 420 is located on the wedge block 330; the locking insulated reversing wheel 430 is located on the top beam 113; the locking SMA wire 410 passes around the locking insulated reversing wheel 430, and the two ends of the locking SMA wire 410 are respectively clamped and fixed on the two locking conductive clamps 420, and the locking SMA wire 410 has a working state of being energized and retracted.

[0037] After adopting the above configuration, the two locking conductive clips 420 are staggered, which makes more reasonable use of the vertical installation space on the support base 110, enabling the locking power unit 400 to provide locking power in such a small space.

[0038] For example, in application, the locking insulating conductor realizes the change of direction of the locking SMA wire 410, and does not affect the formation of an electrical circuit between the locking SMA wire 410 and the two locking conductive clips 420. Therefore, once the locking SMA wire 410 is powered, the locking SMA wire 410 will shorten, thereby driving the wedges 330 on both sides of the object to be locked 200 to move towards each other, thereby achieving the locking of the object to be locked 200.

[0039] It should be noted that, in order to achieve the clamping and fixing of the locking conductive clip 420 on the locking SMA wire 410, such as Figure 7 and Figure 8As shown, this embodiment provides a locking conductive clamp 420 including a locking conductive clamping piece 421, a locking insulating clamping block 422, a locking pressure plate 423, and a locking adjusting bolt 424. The locking conductive clamping piece 421 is clamped within the locking insulating clamping block 422, and the locking conductive clamping piece 421 also holds a locking SMA wire 410. The locking adjusting bolt 424 passes sequentially through the locking pressure plate 423 and the locking insulating clamping block 422. Tightening the locking adjusting bolt 424 is used to press the locking pressure plate 423 against the locking conductive clamping piece 421.

[0040] After adopting the above configuration, the locking conductive clip 421 achieves electrical connection with the locking SMA wire 410, thereby facilitating the energization of the locking SMA wire 410; while the locking insulating clip 422 cuts off the electrical connection between the locking conductive clip 421 and other components, ensuring that the electrical circuit formed between the locking SMA wire 410 and the two locking conductive clips 420 is not affected; and the tightening of the locking adjusting bolt 424 can also adjust the locking force of the locking SMA wire 410, meeting the adjustment needs under different conditions.

[0041] Regarding the aforementioned release power unit 500, as Figure 1 and Figure 7 As shown, this embodiment sets multiple release power units 500. Each release power unit 500 includes a release SMA wire 510, which is connected to the wedge block 330. The deformation of the release SMA wire 510 after being energized is used to pull the wedge block 330 away from the locking member 200, so as to release the pressure block 310 from pressing the locking member 200.

[0042] At this time, the release power unit 500 is mainly used to control the on and off of the release SMA wire 510. Since the release SMA wire 510 is a shape memory alloy, shape memory alloys will produce different deformations under different on and off states. Length deformation is a common change mode of shape memory alloys. Therefore, by using the release power unit 500 to control the on and off state of the release SMA wire 510, the length of the release SMA wire 510 can be controlled, thereby achieving the purpose of pulling the wedge block 330 in a specific direction by the release SMA wire 510.

[0043] Furthermore, in order to reduce the space occupied by the power unit 500, such as Figure 1 and Figure 7As shown, this embodiment of the release power unit 500 also includes a release conductive clamp 520 and a release insulating reversing wheel 530; one release conductive clamp 520 is provided on the top beam 113, and another release conductive clamp 520 is provided on the wedge block 330; the release insulating reversing wheel 530 is provided on the side of the support base 110 away from the locking member 200; the release SMA wire 510 passes around the release insulating reversing wheel 530, and the two ends of the release SMA wire 510 are respectively clamped and fixed on the two release conductive clamps 520, and the release SMA wire 510 has a working state of being energized and retracted.

[0044] After adopting the above configuration, the two release conductive clips 520 are arranged in a staggered manner, which can make more reasonable use of the vertical installation space on the support base 110, so that the release power unit 500 can provide release power with such a small space occupation.

[0045] For example, in application, the release insulating conductor realizes the change of direction of the release SMA wire 510, and does not affect the formation of an electrical circuit between the release SMA wire 510 and the two release conductive clips 520. Therefore, once the release SMA wire 510 is powered, the release SMA wire 510 will shorten, thereby driving the wedges 330 on both sides of the locking member 200 to move away from each other, thereby realizing the unlocking of the locking member 200.

[0046] It should be noted that, in order to achieve the clamping and fixing of the release conductive clip 520 on the release SMA wire 510, such as Figure 7 and Figure 9 As shown, this embodiment provides a release conductive clamp 520 including a release conductive clamp 521, a release insulating clamp 522, a release pressure plate 523, and a release adjusting bolt 524; the release conductive clamp 521 is clamped in the release insulating clamp 522, and the release conductive clamp 521 clamps the release SMA wire 510; the release adjusting bolt 524 passes through the release pressure plate 523 and the release insulating clamp 522 in sequence, and tightening the release adjusting bolt 524 is used to press the release pressure plate 523 to press the release conductive clamp 521.

[0047] After adopting the above configuration, the release conductive clip 521 achieves electrical connection with the release SMA wire 510, thereby facilitating the energization of the release SMA wire 510; while the release insulating clip 522 cuts off the electrical connection between the release conductive clip 521 and other components, ensuring that it does not affect the formation of an electrical circuit between the release SMA wire 510 and the two release conductive clips 520; and the tightening of the release adjusting bolt 524 can also adjust the release force on the release SMA wire 510, meeting the adjustment requirements under different conditions.

[0048] It should also be noted that the present invention provides locking driving force through locking power unit 400 and releasing driving force through releasing power unit 500, thereby realizing repeated locking and releasing of the locking member 200, and also has a self-locking function. Its force analysis can be found by referring to... Figure 10 .

[0049] At this point, if a horizontal force F is applied to the wedge 330 to the left... SMA This generates a clamping force to press the locking component 200 into place. In the diagram, F represents the sum of the reaction force and the elastic force exerted by the locking component 200 on the slider. When force F... SMA After removal, the mechanism, under the action of force F, should self-lock during the reverse stroke, meaning that wedge 330 should not slide to the right. At this time, wedge 330 is subjected to friction from the two contact surfaces of the support base 110 and the pressure block 310. The combined frictional force and the normal force of the contact surfaces is R. AB R CB It indicates, along with the friction angle, when Φ is satisfied AB ≥a-Φ CB When the time is right, self-locking can be achieved.

[0050] In addition to the aforementioned locking and releasing mechanism, the present invention also provides a testing platform, such as... Figure 11 As shown, this embodiment includes a locking and releasing mechanism. The mounting platform 100 is equipped with an coded mounting base 610, and the coded mounting base 610 is equipped with a displacement encoder 620. The signal acquisition point of the displacement encoder 620 is connected to a synchronously rotating pulley 630. A connecting rope 640 is wound around the pulley 630. One end of the connecting rope 640 is connected to the wedge block 330, and the other end of the connecting rope 640 is connected to a pre-tightening weight 650. Furthermore, a force sensor 660 is provided at the bottom of the component to be locked 200. The force sensor 660 is located on the mounting platform 100 and is used to detect the pressure exerted on the component to be locked 200.

[0051] After adopting the above settings, displacement measurement and force response measurement can be achieved, as detailed below: During displacement measurement, once the wedge 330 is displaced by the driving force, it will move the connecting rope 640. Under the action of the pre-tightening weight 650, the connecting rope 640 drives the pulley 630 to rotate a certain angle through contact friction, thereby driving the shaft of the displacement encoder 620 to rotate. Depending on the type of displacement encoder 620, it will output a digital signal or an analog signal. The digital signal is read by a digital signal processor or the analog voltage signal is read by an oscilloscope to obtain the corresponding displacement response data. During digital signal processing, open-loop and closed-loop control of the SMA wire can also be studied based on the processor and Buck circuit.

[0052] When measuring the force response, once the pressure slider moves downward to press the locking part 200, the locking part 200 will transmit the force to the force sensor 660 at the bottom. The force sensor 660 will output an analog voltage signal, and the pressing force response data can be processed in MATLAB using an oscilloscope or similar instrument. Similarly, the corresponding release force response data can be obtained.

[0053] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A locking and releasing mechanism whose clamping and releasing are both triggered by an SMA, characterized in that, Includes an installation platform, a component to be locked, a locking unit, a locking power unit, and a releasing power unit; The installation platform is provided with two oppositely arranged support seats, and each of the two support seats is provided with the locking unit, the locking power unit, and the releasing power unit; The locking component is located between the two support seats; The locking unit includes a pressure block, a return spring, and a wedge block; The pressure block is a structure that can move toward and away from the top of the part to be locked. The pressure block has a force-bearing inclined surface away from the top surface of the part to be locked. The force-bearing inclined surface fits and abuts against the inclined surface of the wedge. The reset spring is used to push the pressure block toward the wedge block; The wedge is held between the support base and the pressure block. The wedge is movable toward and away from the locking member. The moving direction of the wedge is perpendicular to the moving direction of the pressure block. The locking power unit comprises multiple units, each including a locking SMA wire connected to the wedge. The deformation of the locking SMA wire after being energized is used to pull the wedge towards the part to be locked, thereby controlling the wedge to push the pressure block to press the part to be locked. The release power unit comprises multiple units, each including a release SMA wire connected to the wedge. The deformation of the release SMA wire after being energized is used to pull the wedge away from the object to be locked, thereby releasing the pressure of the pressure block on the object to be locked.

2. The locking and releasing mechanism according to claim 1, characterized in that, The top of the component to be locked and the adjacent positions of the two support seats are provided with guide ramps; Both pressure blocks and the two guide ramps are provided with force-applying inclined surfaces at their opposite positions, and the two force-applying inclined surfaces are respectively in contact with the two guide ramps.

3. The locking and releasing mechanism according to claim 1, characterized in that, The support base has a cavity on the surface facing the part to be locked, and a guide pin is provided in the cavity. The guide pin passes through the pressure block and is placed in the cavity. The return spring is sleeved outside the guide pin, and the return spring elastically abuts against the part of the pressure block placed in the cavity.

4. The locking and releasing mechanism according to claim 3, characterized in that, The pressure block is provided with a guide wheel on the surface of the part to be locked away from the surface of the pressure block; The support base is provided with a guide rail, and the guide wheel is slidably mounted on the guide rail.

5. The locking and releasing mechanism according to claim 1, characterized in that, The top of the support base is provided with a top beam; The wedge is held between the top beam and the pressure block. The top surface of the wedge has limiting protrusions on both sides opposite to each other, and the two limiting protrusions abut against the opposite sides of the top beam respectively.

6. The locking and releasing mechanism according to claim 5, characterized in that, The locking power unit also includes a locking conductive clamp and a locking insulated reversing wheel; One of the locking conductive clamps is disposed on the side of the support base away from the member to be locked, and the other of the locking conductive clamps is disposed on the wedge block; The locking insulated reversing wheel is mounted on the top beam; The locking SMA wire passes around the locking insulating reversing wheel, and the two ends of the locking SMA wire are respectively clamped and fixed on the two locking conductive clamps. The locking SMA wire has a working state of being energized and contracted.

7. The locking and releasing mechanism according to claim 6, characterized in that, The locking conductive clamp includes a locking conductive clamping plate, a locking insulating clamping block, a locking pressure plate, and a locking adjusting bolt; The locking conductive clip is held in the locking insulating clip block, and the locking conductive clip holds the locking SMA wire; The locking adjusting bolt passes sequentially through the locking pressure plate and the locking insulating clamp. Tightening the locking adjusting bolt is used to press the locking pressure plate against the locking conductive clamp.

8. The locking and releasing mechanism according to claim 5, characterized in that, The release power unit also includes a release conductive clamp and a release insulated reversing wheel; One of the release conductive clips is disposed on the top beam, and the other of the release conductive clips is disposed on the wedge block; The release insulated reversing wheel is located on the side of the support base away from the locking member; The release SMA wire passes around the release insulating reversing wheel, and the two ends of the release SMA wire are respectively clamped and fixed on the two release conductive clamps. The release SMA wire has a working state of being energized and contracted.

9. The locking and releasing mechanism according to claim 8, characterized in that, The release conductive clamp includes a release conductive clamping plate, a release insulating clamping block, a release pressure plate, and a release adjusting bolt; The release conductive clip is held within the release insulating clip, and the release conductive clip holds the release SMA wire; The release adjusting bolt passes sequentially through the release pressure plate and the release insulating clamp. Tightening the release adjusting bolt is used to press the release pressure plate against the release conductive clamp.

10. A testing platform comprising the locking and releasing mechanism according to any one of claims 1 to 9, characterized in that, The installation platform is equipped with an encoding mounting base, and the encoding mounting base is equipped with a displacement encoder. The signal acquisition point of the displacement encoder is connected to a synchronously rotating pulley. A connecting rope is wound around the pulley. One end of the connecting rope is connected to the wedge block, and the other end of the connecting rope is connected to a preload weight. Furthermore, a force sensor is provided at the bottom of the component to be locked, and the force sensor is located on the mounting platform. The force sensor is used to detect the pressure exerted on the component to be locked.

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