Driving device based on memory alloy wire

Abstract

The invention provides a driving device based on a memory alloy wire, which comprises a substrate, a positive terminal, a negative terminal, a load assembly capable of vertically moving and a pulley block containing a fixed pulley, and adopts a memory alloy wire multi-section winding structure, one end of the memory alloy wire is connected with the positive terminal, and the other end of the memory alloy wire is connected with the negative terminal. The other end of the alloy wire is sequentially connected with the upper end of the load assembly, passes through the pulley block to form a transmission path and then is connected with the negative terminal; the device is provided with a vertical guide window for guiding an alloy wire motion path, a supporting rod and a clamping groove interference fit structure achieve rolling friction contact, and motion resistance is reduced. And in cooperation with the design of the nickel-titanium alloy integrally-formed wire and the sealing shell, the advantages of being compact in structure, high in response speed and long in service life are achieved. The device solves the problems of large noise, high energy consumption, high cost and low reliability of a traditional driving motor, and is suitable for scenes needing linear displacement driving such as an intelligent controller.

Description

Technical Field

[0001] The present invention relates to the field of intelligent drive technology, and particularly to a drive device based on shape memory alloy wires. Background Art

[0002] Traditional linear drive devices mostly adopt electromagnetic motors, hydraulic or pneumatic drive methods, which have problems such as being bulky, noisy, high energy consumption, and complex structure. Although drives based on shape memory alloy (SMA) have gradually attracted attention due to advantages such as shape memory effect and silent drive, in the prior art, drive devices using shape memory alloy wires generally have defects of short contraction stroke and insufficient driving force. For example, when a single shape memory alloy wire directly drives a load, the contraction displacement is limited by the material deformation rate, making it difficult to meet the requirements of long stroke and precise control. At the same time, the alloy wire is prone to sliding friction with the guiding structure during reciprocating motion, resulting in large energy loss and reduced service life. In addition, most existing devices lack effective sealing protection for the working environment of the alloy wire, and are easily interfered by the outside under complex working conditions, affecting the driving stability. Therefore, how to achieve stroke amplification, reduce motion resistance, reduce the device volume, and improve the overall reliability through structural innovation has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0003] In view of the deficiencies in the prior art, the present invention proposes a drive device based on shape memory alloy wires.

[0004] The present invention proposes a drive device based on shape memory alloy wires, including a substrate;

[0005] A positive terminal and a negative terminal are fixedly arranged on the substrate at intervals;

[0006] A load assembly is movable in a direction perpendicular to the substrate;

[0007] A pulley group includes at least two fixed pulleys, and the fixed pulleys are fixedly installed on the substrate through brackets;

[0008] A shape memory alloy wire, its first end is connected to the positive terminal, and the second end is sequentially connected to the upper end of the load assembly, passes through the pulley group to form multiple transmission paths for doubling the contraction stroke, and finally is connected to the negative terminal;

[0009] Wherein, when power is applied to the positive terminal and the negative terminal, the shape memory alloy wire is heated and shrinks to generate a driving force, driving the load assembly to make a linear displacement in the vertical direction.

[0010] Preferably, a vertically extending guiding window is formed on the substrate. The guiding window is located in the area between the positive terminal and the load assembly, and its extending direction is parallel to the moving direction of the load assembly. The shape memory alloy wire passes through the guiding window and is fixedly connected to the upper end of the load assembly.

[0011] Preferably, a pair of supporting blocks symmetrically extend from both sides of the upper end of the guiding window. A clamping groove is formed at the top of each supporting block; both ends of the supporting rod are fixedly installed in the clamping groove by interference fit. The axis of the supporting rod is parallel to the substrate plane and perpendicular to the moving direction of the load assembly; the shape memory alloy wire winds around the supporting rod and forms a rolling friction contact with the surface of the supporting rod.

[0012] Preferably, the clamping groove includes a guiding section and a locking section. The guiding section is an inverted conical structure, and the locking section is a cylindrical blind hole. The end of the supporting rod is guided into the locking section along the guiding section and is fixed by interference fit.

[0013] Preferably, bearings are arranged between the two ends of the supporting rod and the inner wall of the locking section of the clamping groove. The inner ring of the bearing is fixedly installed at the end of the supporting rod by interference fit, and the outer ring is installed on the inner wall of the locking section by transitional fit.

[0014] Preferably, the shape memory alloy wire is integrally formed of nickel-titanium alloy material, and includes a horizontal moving section winding around a pulley group and a vertical driving section connecting the load assembly. The horizontal moving section and the vertical driving section are connected by an arc transition section.

[0015] Preferably, a housing is further included. The housing is hermetically connected to the substrate by screws to form a closed cavity. A wire through hole is formed on one side wall of the housing, and a gap is maintained between the inner wall of the housing and the shape memory alloy wire.

[0016] The technical effects of the driving device based on the shape memory alloy wire provided by the present invention are as follows:

[0017] 1. Stroke multiplication and high-efficiency driving: By using the multi-stage winding design of the pulley group, the deformation of the shape memory alloy wire is converted into the vertical displacement of the load assembly through path multiplication. Under the condition of a limited alloy wire length, several times of stroke amplification is achieved, significantly improving the driving efficiency, reducing the volume of the device, and realizing the miniaturization of the driving device.

[0018] 2. Low friction and long service life: By restricting the movement track of the alloy wire through the guiding window and cooperating with the interference fit structure of the supporting rod and the clamping groove, the alloy wire forms a rolling friction contact with the supporting rod, reducing friction loss and extending the service life.

[0019] 3. Compactness and environmental adaptability: The use of a shape memory alloy wire made of nickel-titanium alloy by one-piece forming and the design of a sealed housing not only ensure the compactness of the structure but also avoid the influence of external pollution or temperature and humidity changes on the performance of the alloy wire, thus enhancing the reliability of the device in complex environments.

[0020] 4. Energy-saving and noise-reduction advantages: Compared with traditional electromagnetic motors, this device does not require mechanical transmission components and directly controls the deformation of the alloy wire through current, featuring low energy consumption and no mechanical noise, and is suitable for precision drive scenarios such as intelligent controllers and micro-robots.

[0021] This device effectively solves the pain points of traditional drive motors, such as high noise, high energy consumption, high cost, low reliability, and insufficient stroke of existing shape memory alloy drivers, and provides a lightweight, miniaturized, and high-precision solution for linear displacement drive. Brief Description of the Drawings

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following-described drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0023] Figure 1 is a schematic structural diagram of the drive device based on a shape memory alloy wire according to an embodiment of the present invention;

[0024] Figure 2 is a schematic overall structural diagram of the drive device based on a shape memory alloy wire according to an embodiment of the present invention;

[0025] Figure 3 is one of the schematic partial structural diagrams of the drive device based on a shape memory alloy wire according to an embodiment of the present invention;

[0026] Figure 4 is another schematic partial structural diagram of the drive device based on a shape memory alloy wire according to an embodiment of the present invention;

[0027] Figure 5 is still another schematic partial structural diagram of the drive device based on a shape memory alloy wire according to an embodiment of the present invention;

[0028] Figure 6 is a schematic structural diagram of the substrate and support rod of the drive device based on a shape memory alloy wire according to an embodiment of the present invention.

[0029] Reference numerals: substrate 1; positive terminal 2; negative terminal 3; load assembly 4; pulley block 5; bracket 6; shape memory alloy wire 7; horizontal movement section 71; vertical drive section 72; guide window 9; support block 10; card slot 11; introduction section 11a; locking section 11b; support rod 12; housing 13; screw 14. Detailed implementation

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] Please refer to Figures 1 to 6 , the drive device based on the shape memory alloy wire in this embodiment includes: a substrate 1, a positive terminal 2, a negative terminal 3, a load assembly 4, a pulley block 5, a shape memory alloy wire 7, and a housing 13.

[0032] The positive terminal 2 and the negative terminal 3 are fixedly arranged at intervals on the edge of the substrate 1. The load assembly 4 is located below the substrate 1 and can move up and down perpendicular to the substrate direction. The load assembly 4 is a driven element, such as the reset button of a leakage protection socket. The pulley block 5 includes 4 fixed pulleys, and each fixed pulley is fixedly installed on the substrate 1 through a bracket 6. The first end of the shape memory alloy wire 7 is connected to the positive terminal 2, and the second end is sequentially connected to the upper end of the load assembly 4, passes around the 4 fixed pulleys of the pulley block 5 to form a multi-segment transmission path with a multiplied contraction stroke, and finally is connected to the negative terminal 3.

[0033] A vertically extending guide window 9 is opened on the substrate 1. The guide window 9 is located in the area between the positive terminal 2 and the load assembly 4, and its extending direction is parallel to the moving direction of the load assembly 4. The shape memory alloy wire 7 passes through the guide window 9 and is fixedly connected to the upper end of the load assembly 4.

[0034] When power is applied to the positive terminal 2 and the negative terminal 3, the shape memory alloy wire 7 contracts due to heat and generates a driving force, driving the load assembly 4 (reset button) to perform a linear displacement in the vertical direction, so as to realize the reset of the reset button of the leakage protection socket.

[0035] A pair of support blocks 10 symmetrically extend from both sides of the upper end of the guide window 9, and a card slot 11 is opened at the top of each support block 10. Both ends of the support rod 12 are fixed in the card slot 11 by interference fit. The axis of the support rod 12 is parallel to the substrate plane and perpendicular to the moving direction of the load assembly 4.

[0036] The card slot 11 includes an introduction section 11a and a locking section 11b. The introduction section 11a is of an inverted conical structure, and the locking section 11b is a cylindrical blind hole. The end of the support rod 12 is introduced into the locking section 11b along the introduction section 11a and fixed by interference fit. The shape memory alloy wire 7 is wound around the support rod 12 and forms a sliding friction contact with the surface of the support rod 12.

[0037] Bearings (not shown in the figure) can also be provided between the two ends of the support rod 12 and the inner wall of the locking section 14 of the card slot 11. The inner ring of the bearing is fixed to the end of the support rod 12 by interference fit, and the outer ring is installed on the inner wall of the locking section 11b by transitional fit. The shape memory alloy wire 7 is wound around the support rod 12 and forms a rolling friction contact with the surface of the support rod 12, reducing the frictional force between the shape memory alloy wire 7 and the surface of the support rod 12.

[0038] The shape memory alloy wire 7 is integrally formed of a nickel-titanium alloy material and includes a horizontal moving section 71 that winds around 4 fixed pulleys of the pulley group 5 and a vertical driving section 72 that connects the load assembly 4. The horizontal moving section 71 and the vertical driving section 72 are connected by an arc transition section.

[0039] A housing 13 is also provided on the substrate 1. The housing 13 is hermetically connected to the substrate 1 by screws 14 to form a closed cavity. A wire through hole is provided on one side wall of the housing 13. The positive terminal 2 and the negative terminal 3 are connected to an external control power supply through wires passing through the wire through hole. A radial gap of 3 - 5 cm is maintained between the inner wall of the housing 13 and the shape memory alloy wire 7 to prevent the housing 13 from interfering with the movement of the shape memory alloy wire 7.

[0040] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A driving device based on memory alloy wire, characterized in that: include: base(1); The positive electrode terminal (2) and the negative electrode terminal (3) are fixedly arranged on the substrate (1) at intervals from each other; A load assembly (4) movable perpendicular to the substrate; A pulley block (5) comprises at least two fixed pulleys, wherein the fixed pulleys are fixedly mounted on the base plate (1) via a bracket (6); A memory alloy wire (7), the first end of which is connected to the positive terminal (2), the second end of which is sequentially connected to the upper end of the load component (4), passes through the pulley block (5) to form a multi-stage transmission path with a multiplied contraction stroke, and finally is connected to the negative terminal (3); When electricity is supplied to the positive electrode terminal (2) and the negative electrode terminal (3), the memory alloy wire (7) contracts due to heat to generate a driving force, driving the load component (4) to perform linear displacement in a vertical direction.

2. The driving device according to claim 1, characterized in that: The base plate (1) is provided with a vertically extending guide window (9), the guide window (9) being located in a region between the positive electrode terminal (2) and the load component (4), and its extending direction being parallel to the moving direction of the load component (4), and the memory alloy wire (7) passing through the guide window (9) is fixedly connected to the upper end of the load component (4).

3. The driving device according to claim 2, characterized in that: The upper ends of the guide windows (9) are symmetrically extended on both sides to form a pair of support blocks (10), and a slot (11) is provided on the top of each support block (10); Both ends of the support rod (12) are fixed in the clamping groove (11) by interference fit, and the axis of the support rod (12) is parallel to the plane of the substrate and perpendicular to the moving direction of the load component (4); The memory alloy wire (7) is wound around the support rod (12) and forms rolling friction contact with the surface of the support rod (12).

4. The drive device gas valve according to claim 3, characterized in that: The slot (11) comprises an introduction section (11a) and a locking section (11b); the introduction section (11a) is an inverted cone structure; the locking section (11b) is a cylindrical blind hole; the end of the support rod (12) is introduced into the locking section (11b) along the introduction section (11a) and is fixed by interference fit.

5. The driving device according to claim 4, characterized in that: Bearings are provided between the two ends of the support rod (12) and the inner wall of the locking section (11b) of the slot (11); the inner ring of the bearing is fixed to the end of the support rod by interference fit, and the outer ring is installed on the inner wall of the locking section (11b) by transition fit.

6. The driving device according to claim 1, characterized in that: The memory alloy wire (7) is integrally formed of a nickel-titanium alloy material, and comprises a horizontal moving section (71) wound around a pulley block (5) and a vertical driving section (72) connected to a load component (4); the horizontal moving section (71) and the vertical driving section (72) are connected via a circular arc transition section.

7. The driving device according to claim 1, characterized in that: It also comprises a shell (13), the shell (13) being sealedly connected to the substrate (1) via screws (14) to form a closed cavity, a wire through-hole being provided on one side wall of the shell (13), and a gap being maintained between the inner wall of the shell (13) and the memory alloy wire (7).

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