SMA-driven multi-degree-of-freedom intelligent electric wrench

Abstract

The invention discloses an SMA-driven multi-degree-of-freedom intelligent electric wrench, which relates to the technical field of fastening and dismounting tools, and is provided with a variable caliber unit D comprising a folding and unfolding assembly, an SMA spring, a heat conducting strip, a mounting rod and a radiator; the mounting rod sleeves the transmission shaft, and the front end of the mounting rod is fixedly mounted with the handle; the radiator is fixedly installed on the installation rod in the circumferential direction of the installation rod, the folding and unfolding assembly is connected with the rear end of the transmission shaft through the center shaft, the motor drives the folding and unfolding assembly to rotate around the axis of the center shaft in a fixed-axis mode, and the SMA spring is electrically communicated with the power source and communicated with the radiator through the heat conduction strip for heat exchange. The folding and unfolding assembly can be folded or unfolded under the action of the SMA spring, at least three corners are always kept to be unfolded, inner hexagonal threaded parts with different calibers can be fastened and disassembled under the condition that the assembly is not replaced, the portability and the working efficiency of the inner hexagonal wrench are greatly improved, and the inner hexagonal wrench is simple in structure, light, efficient, environmentally friendly and suitable for popularization and application. And meanwhile, the manufacturing cost is favorably controlled.

Description

Technical Field

[0001] The invention relates to the technical field of fastening and disassembling tools, and in particular to a wrench used for fastening or disassembling threaded parts of different specifications. Background Art

[0002] An Allen wrench is a tool used to tighten and remove hexagonal threaded parts. In order to correspond to the various specifications of hexagonal threaded parts, Allen wrenches usually need to be set up in sets, which are inconvenient to store and carry. At the same time, when using a set of Allen wrenches to tighten or remove hexagonal threaded parts, you first need to confirm the specifications of the hexagonal threaded parts, and then use the Allen wrench corresponding to the model to tighten or remove them. The process is cumbersome and the work efficiency is not ideal. In addition, existing Allen wrenches are not well suited to working environments such as narrow spaces. There are problems with difficulty in applying force and inconvenient operation, which makes the disassembly work difficult or even impossible.

[0003] Prior art 1: a wrench Application number: 201510223782.X, application date: 2015.05.05, publication (announcement) date: 2016.12.07.

[0004] Prior art 1 discloses a wrench for turning a workpiece, which includes a one-way transmission mechanism. The one-way transmission mechanism includes a roller, a first component, and a second component at least partially sleeved in the first component; the first component is fixedly arranged on the turning part of the wrench, and the second component is used to cooperate with the workpiece. The direction of the torque from the turning part is the first direction and the second direction along the rotation axis of the first component; for one of the torque in the first direction and the torque in the second direction, the second component is stationary relative to the first component to output the torque to the workpiece; for the other one, the second component rotates relative to the first component without outputting the torque to the workpiece. The one-way transmission mechanism of the present invention does not have a high-speed rotation requirement, so its torque can meet the use requirements of the wrench, so the wrench of the present invention can be comparable to the wrench of the prior art. At the same time, the one-way transmission mechanism remains silent during use and has the characteristics of wear-resistant bearings.

[0005] However, the length of the prior art 1 itself is still fixed, which limits its use in narrower and more complex environments.

[0006] Prior art 2: a wrench Application number 202111522102.6, application date 2021.12.13, authorization announcement date 2024.01.26.

[0007] Prior art 2 discloses a wrench, including a torque output component for screwing a fastener and a retraction angle confirmation component rotatably arranged on the torque output component and used to determine the retraction angle of the fastener, a plurality of scale lines are arranged on the surface of the retraction angle confirmation component, and a marking arrow pointing to the scale line is arranged on the surface of the torque output component. The wrench of the present invention integrates two output modes, angle output and torque output, and can tighten the workpiece to a specified torque first and then retract the specified angle, saving the time of changing tools and improving efficiency.

[0008] However, the wrenches in the prior art still use fixed calibers. When installing screws of different sizes, wrenches of different calibers still need to be frequently replaced, causing inconvenience in use.

[0009] Through the above search, it is found that the above technical solutions do not affect the novelty of the present invention; and the mutual combination of the above prior arts does not destroy the creativity of the present invention. Summary of the invention

[0010] In order to avoid the above-mentioned deficiencies in the prior art, the present invention provides a SMA-driven multi-degree-of-freedom intelligent electric wrench.

[0011] The present invention adopts the following technical solution to solve the technical problem: an SMA-driven multi-degree-of-freedom intelligent electric wrench, a mounting cavity is provided in the handle, a motor and a power supply are fixedly installed in the mounting cavity, and the output end of the motor is axially connected to the front end of the transmission shaft; The above-mentioned intelligent electric wrench is provided with a variable-caliber unit D including a folding and unfolding assembly, an SMA spring, a heat-conducting strip, a mounting rod and a heat sink; The mounting rod is a hollow tubular structure, which is sleeved outside the transmission shaft and has a gap between the mounting rod and the transmission shaft, and the front end of the mounting rod is fixedly mounted on the handle; the radiator is arranged around the mounting rod and fixedly mounted on the mounting rod; The folding and unfolding assembly is connected to the rear end of the transmission shaft via a central shaft, and the motor drives the folding and unfolding assembly to rotate around the axis of the central shaft; The SMA spring is electrically connected to the power source and is connected to the heat sink for heat exchange through the heat conductive strip; when the SMA spring is powered on, it heats up and contracts, driving the folding assembly to fold and gather until the folding assembly can be inserted into the hexagonal hole of the threaded part; when the power is off, it cools down and expands, driving the folding assembly to expand and open until the folding assembly engages with the hexagonal hole.

[0012] Furthermore, the folding and unfolding assembly includes six folding and unfolding units of triangular frame structures; The six folding and unfolding units are arranged and assembled along the circumference of the central axis, and the vertices of the folding and unfolding units close to the central axis are connected to the connecting column for sliding installation, and are connected to the central axis for rotation installation through the connecting column; a rotating pair is formed between the folding and unfolding units and the central axis for supporting the folding and unfolding units to swing up or down, and a sliding pair is formed between the folding and unfolding units and the connecting column for supporting the folding and unfolding units to slide toward or away from the central axis along the connecting column; The spliced ​​edges of the adjacent folding and unfolding units are hinged with the boundary line as the rotation axis, so as to form the folding and unfolding component which has a hexagonal pyramid-like structure when fully extended and opened; The six folding units are divided into three adjacent pairs, and each pair of the folding units is correspondingly equipped with an SMA spring. The two ends of the SMA spring are respectively connected to the two vertices of the non-hinged edges of the corresponding pair of folding units. When the SMA spring is energized, it heats up and contracts, driving the corresponding pair of folding units to fold and close. When the power is off, it cools down and extends, driving the corresponding pair of folding units to extend and open.

[0013] Furthermore, a bending unit E is provided between the central shaft and the rear end of the transmission shaft; The bending unit E has bending adjustment and fixing functions, and transmits the rotation output by the motor to the folding and unfolding assembly via the transmission shaft and the central shaft, driving the folding and unfolding assembly to rotate around the axis of the central shaft.

[0014] Further, the bending unit E includes a first universal joint group, a second universal joint group, a positioning ring and a solid tube; The first universal joint assembly and the second universal joint assembly each include a pair of cross-type universal joints sharing a central universal joint fork; a first input universal joint fork at the input end of the first universal joint assembly is axially coupled to the rear end of the transmission shaft, a first output universal joint fork at the output end is axially coupled to a second input universal joint fork at the input end of the second universal joint assembly, and a second output universal joint fork at the output end of the second universal joint assembly is axially coupled to the central shaft; The first input universal yoke fork, the first output universal yoke fork, the second input universal yoke fork and the second output universal yoke fork are all rotatably sleeved with the positioning ring forming a rotation pair around their own axis; The positioning ring is fixed by a solid tube and can adjust its posture by following the bending of the solid tube.

[0015] Furthermore, the front end of the solid tube is fixedly installed, and the end is a forked structure, and the forked structure is respectively fixedly connected to each of the positioning rings.

[0016] Furthermore, the front end of the solid tube is fixedly connected to the radiator through the heat conducting strip.

[0017] Furthermore, the solid tube is a gooseneck tube.

[0018] Furthermore, the SMA spring is connected to the heat-conducting strip through the solid tube for heat exchange.

[0019] Furthermore, a motor switch for controlling the operation of the motor and a power switch for controlling the operation of the SMA spring are provided at the rear end of the handle.

[0020] Furthermore, the heat sink includes copper heat sinks that are evenly and densely distributed.

[0021] The present invention provides a multi-degree-of-freedom intelligent electric wrench driven by an SMA, which has the following beneficial effects: 1. The folding and unfolding assembly of the present invention can be folded or stretched under the action of the SMA spring, and always maintains at least three angles stretched, and can realize the fastening and disassembly of hexagonal screw parts of different calibers without replacing the assembly, which greatly improves the portability and work efficiency of the hexagonal wrench and is conducive to the control of its manufacturing cost.

[0022] 2. The folding and unfolding of the folding and unfolding assembly of the present invention is controlled by the SMA spring's power-on heating and power-off cooling, and has a simple structure, is lightweight, highly efficient and environmentally friendly.

[0023] 3. The bending unit of the present invention makes the position and posture of the folding and unfolding assembly adjustable, and can adapt to the working environment of narrow and complex space; at the same time, the operator can control the wrench in a position and posture that is easy to operate, which further improves the work efficiency and at the same time reduces the burden on the operator's wrist, reducing the difficulty and labor intensity of disassembling and assembling hexagonal threaded parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 It is a partial enlarged structural schematic diagram of the present invention; Figure 3 It is a schematic diagram of the axonometric structure of the folding and unfolding assembly of the present invention in an unfolded state; Figure 4 It is a bottom view structural schematic diagram of the folding and unfolding assembly of the present invention in the unfolded state; Figure 5 It is a schematic diagram of the axonometric structure of the folding assembly of the present invention in a folded state; Figure 6 It is a bottom view structural schematic diagram of the folding assembly of the present invention in a folded state.

[0025] In the figure: 1. Handle, 2. Motor switch, 3. Power switch, 6. Heat conductive strip, 7. Solid tube, 8. Transmission shaft, 9. Radiator, 10. First universal joint group, 11. Second universal joint group, 12. SMA spring, 13. Folding and unfolding assembly, 14. Center axis, 15. Mounting rod, 16. Positioning ring, 17. First input universal joint fork, 18. First output universal joint fork, 19. Second input universal joint fork, 20. Second output universal joint fork, D. Variable-caliber unit, E. Bending unit. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] A multi-degree-of-freedom intelligent electric wrench driven by SMA, such as Figure 1 to Figure 6 As shown, the structural relationship is as follows: a mounting cavity is provided in the handle 1, the motor and the power supply are fixedly installed in the mounting cavity, and the output end of the motor is axially connected to the front end of the transmission shaft 8; The handle 1 enables the operator to hold the electric wrench conveniently, while protecting the internal structure and improving the overall stability of the structure; The above-mentioned SMA-driven multi-degree-of-freedom intelligent electric wrench is provided with a variable-caliber unit D including a folding and unfolding assembly 13, an SMA spring 12, a heat-conducting strip 6, a mounting rod and a heat sink 9; The mounting rod is a hollow tubular structure, which is sleeved outside the transmission shaft 8, and a gap is left between the transmission shaft 8, and the front end of the mounting rod is fixedly mounted on the handle 1; the radiator 9 is arranged around the circumference of the mounting rod and fixedly mounted on the mounting rod; The folding and unfolding assembly 13 is connected to the rear end of the transmission shaft 8 through the central shaft 14, and the motor drives the folding and unfolding assembly 13 to rotate around the axis of the central shaft 14; The SMA spring 12 is electrically connected to the power supply and is connected to the heat sink 9 through the heat conductive strip 6 for heat exchange; when the SMA spring 12 is powered on, it heats up and contracts, driving the folding assembly 13 to fold and gather until the folding assembly 13 can be placed in the hexagonal hole of the threaded part; when the power is off, it cools down and expands, driving the folding assembly 13 to expand and open until the folding assembly 13 is engaged with the hexagonal hole.

[0028] Preferably, the folding and unfolding assembly 13 includes six folding and unfolding units of a triangular frame structure; The six folding and unfolding units are arranged and assembled along the circumference of the central axis 14. The vertices of the folding and unfolding units close to the central axis 14 are connected to the connecting column for sliding installation, and are connected to the central axis 14 for rotation installation through the connecting column. A rotating pair is formed between the folding and unfolding units and the central axis 14 to support the folding and unfolding units to swing up or down, and a sliding pair is formed between the folding and unfolding units and the connecting column to support the folding and unfolding units to slide toward or away from the central axis 14 along the connecting column. The spliced ​​edges of the adjacent folding and unfolding units are hinged with the intersection line as the rotation axis, forming a folding and unfolding component 13 with a hexagonal pyramid-like structure when fully extended and opened; When the folding and unfolding assembly 13 is in any posture, at least three corners are stretched to adapt to hexagon sockets of different sizes; The six folding units are divided into three adjacent pairs, and each pair of folding units is equipped with an SMA spring 12. The two ends of the SMA spring 12 are respectively connected to the two vertices of the non-hinged edges of the corresponding pair of folding units. When the SMA spring 12 is powered on, it heats up and contracts, driving the corresponding pair of folding units to fold and close. When the power is off, it cools down and extends, driving the corresponding pair of folding units to extend and open.

[0029] Preferably, a bending unit E is further provided between the central shaft 14 and the rear end of the transmission shaft 8; The bending unit E has the functions of bending adjustment and fixing, and transmits the rotation output by the motor to the folding assembly 13 via the transmission shaft 8 and the central shaft 14 , driving the folding assembly 13 to rotate around the axis of the central shaft 14 .

[0030] Preferably, the bending unit E includes a first universal joint assembly 10, a second universal joint assembly 11, a positioning ring 16 and a solid tube 7; The first universal joint assembly 10 and the second universal joint assembly 11 each include a pair of cross-type universal joints that share a central universal joint fork; a first input universal joint fork 17 at the input end of the first universal joint assembly 10 is axially coupled to the rear end of the transmission shaft 8, a first output universal joint fork 18 at the output end is axially coupled to a second input universal joint fork 19 at the input end of the second universal joint assembly 11, and a second output universal joint fork 20 at the output end of the second universal joint assembly 11 is axially coupled to the central shaft 14; The first input universal yoke 17, the first output universal yoke 18, the second input universal yoke 19 and the second output universal yoke 20 are all rotatably sleeved with a positioning ring 16 forming a rotation pair around their own axis; The positioning ring 16 is installed and fixed by the solid tube 7 and can adjust its posture following the bending of the solid tube 7 .

[0031] The first universal joint group 10 and the second universal joint group 11 provide the folding and unfolding component 13 with the freedom of position and posture adjustment to adapt to the working environment in a narrow or complex space. During the adjustment process, the solid tube 7 should be adaptively bent and adjusted; after the adjustment is completed, the solid tube 7 is solidified, and the first universal joint group 10 and the second universal joint group 11 are limited in position during the process of the motor driving the folding and unfolding component 13 to rotate, and only the first input universal joint fork 17, the first output universal joint fork 18, the second input universal joint fork 19 and the second output universal joint fork 20 are allowed to rotate around their own axes. The first universal joint group 10 and the second universal joint group 11 both have the function of offsetting the rotational differential, so that the motor can drive the folding and unfolding component 13 to rotate around the axis of the central axis 14; at the same time, the first universal joint group 10 and the second universal joint group 11 are arranged so that the bending unit E can provide more degrees of freedom of movement, thereby making the position and posture adjustment of the folding and unfolding component 13 more flexible.

[0032] Preferably, the front end of the solid tube 7 is fixedly installed, and the end is a forked structure, and the forked structure is respectively fixedly connected to each positioning ring 16.

[0033] Preferably, the front end of the solid tube 7 is fixedly connected to the radiator 9 via the heat conducting strip 6 .

[0034] Preferably, the solid tube 7 is a gooseneck tube.

[0035] Preferably, the SMA spring 12 is connected to the heat conducting strip 6 through the solid tube 7 for heat exchange.

[0036] Preferably, a motor switch 2 for controlling the operation of the motor and a power switch 3 for controlling the operation of the SMA spring 12 are provided at the rear end of the handle 1 .

[0037] Preferably, the heat sink 9 includes copper heat sinks that are evenly and densely distributed.

[0038] The use of the multi-degree-of-freedom intelligent electric wrench driven by the SMA to tighten or remove the hexagonal threaded parts includes the following processes: In the first step, the SMA spring 12 is energized by the power switch 3, so that the SMA spring 12 heats up and contracts, driving the folding assembly 13 to fold and close.

[0039] In the second step, according to the needs of the working environment, the fixing tube 7 is bent and adjusted so that the folding and unfolding assembly 13 is directly opposite to the hexagonal hole of the hexagonal threaded member.

[0040] In the third step, the folding assembly 13 is inserted into the hexagonal hole, and then the SMA spring 12 is powered off by the power switch 3; the heat of the SMA spring 12 is transferred to the radiator 9 through the fixing tube 7 and the heat conducting strip 6, and the heat is quickly dissipated under the action of the radiator 9, and the SMA spring 12 cools down and stretches, driving the folding assembly 13 to stretch and open, and firmly engage in the hexagonal hole.

[0041] The fourth step is to control the operation of the motor through the motor switch 2. The power of the motor is transmitted to the folding assembly 13 through the transmission shaft 8, the first universal joint group 10, the second universal joint group 11 and the center shaft 14 under the limiting action of each positioning ring 16, driving the folding assembly 13 to rotate around the axis of the center shaft 14 to achieve the tightening or disassembly of the hexagonal threaded parts.

[0042] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0043] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An SMA-driven multi-degree-of-freedom intelligent electric wrench, wherein a handle (1) is provided with an installation cavity, a motor and a power supply are fixedly installed in the installation cavity, an output end of the motor is axially coupled to a front end of a transmission shaft (8), and the characteristics are: A variable-caliber unit (D) is provided, which includes a folding and unfolding assembly (13), an SMA spring (12), a heat-conducting strip (6), a mounting rod and a heat sink (9); The mounting rod is a hollow tubular structure, which is sleeved outside the transmission shaft (8) and has a gap between the mounting rod and the transmission shaft (8), and the front end of the mounting rod is fixedly mounted on the handle (1); the radiator (9) is arranged around the circumference of the mounting rod and is fixedly mounted on the mounting rod; The folding and unfolding assembly (13) is connected to the rear end of the transmission shaft (8) via a central shaft (14), and the motor drives the folding and unfolding assembly (13) to rotate around the axis of the central shaft (14); The SMA spring (12) is electrically connected to the power source and is connected to the heat sink (9) via the heat conductive strip (6) for heat exchange; when the SMA spring (12) is powered on, it heats up and contracts, driving the folding assembly (13) to fold and gather until the folding assembly (13) can be inserted into the hexagonal hole of the threaded part; when the power is off, it cools down and expands, driving the folding assembly (13) to expand and open until the folding assembly (13) engages with the hexagonal hole.

2. The SMA-driven multi-degree-of-freedom intelligent electric wrench according to claim 1, characterized in that: The folding and unfolding assembly (13) comprises six folding and unfolding units of a triangular frame structure; The six folding and unfolding units are arranged around and assembled along the circumference of the central axis (14); the vertices of the folding and unfolding units close to the central axis (14) are slidably mounted and connected to the connecting column, and are rotationally mounted and connected to the central axis (14) through the connecting column; a rotation pair is formed between the folding and unfolding units and the central axis (14) to support the folding and unfolding units to swing up or down, and a sliding pair is formed between the folding and unfolding units and the connecting column to support the folding and unfolding units to slide toward or away from the central axis (14) along the connecting column; The spliced ​​edges of the adjacent folding and unfolding units are hinged with the boundary line as the rotation axis, so as to form the folding and unfolding component (13) which has a hexagonal pyramid-like structure when fully extended and opened; The six foldable units are divided into three adjacent pairs, each pair of the foldable units is provided with an SMA spring (12), the two ends of the SMA spring (12) are respectively connected to the two vertices of the non-hinged edges of the corresponding pair of foldable units, and the SMA spring (12) heats up and contracts when powered on, driving the corresponding pair of foldable units to fold and close, and cools down and extends when powered off, driving the corresponding pair of foldable units to extend and open.

3. The SMA-driven multi-degree-of-freedom intelligent electric wrench according to claim 1 or 2, characterized in that: A bending unit (E) is also provided between the central shaft (14) and the rear end of the transmission shaft (8); The bending unit (E) has bending adjustment and shaping functions, and transmits the rotation output by the motor to the folding and unfolding component (13) via the transmission shaft (8) and the central shaft (14), thereby driving the folding and unfolding component (13) to rotate around the axis of the central shaft (14).

4. The SMA-driven multi-degree-of-freedom intelligent electric wrench according to claim 1, characterized in that: The bending unit (E) comprises a first universal joint assembly (10), a second universal joint assembly (11), a positioning ring (16) and a solid tube (7); The first universal joint assembly (10) and the second universal joint assembly (11) each comprise a pair of cross-type universal joints that share a common central universal joint fork; a first input universal joint fork (17) at the input end of the first universal joint assembly (10) is axially coupled to the rear end of the transmission shaft (8), a first output universal joint fork (18) at the output end is axially coupled to a second input universal joint fork (19) at the input end of the second universal joint assembly (11), and a second output universal joint fork (20) at the output end of the second universal joint assembly (11) is axially coupled to the central shaft (14); The first input universal yoke (17), the first output universal yoke (18), the second input universal yoke (19) and the second output universal yoke (20) are all rotatably sleeved with the positioning ring (16) which forms a rotation pair around its own axis with the positioning ring; The positioning ring (16) is installed and fixed via the solid tube (7), and can adjust its posture by following the bending of the solid tube (7).

5. The SMA-driven multi-degree-of-freedom intelligent electric wrench according to claim 4, characterized in that: The front end of the solid tube (7) is fixedly installed, and the rear end is a forked structure, wherein the forked structures are respectively fixedly connected to each of the positioning rings (16).

6. The SMA-driven multi-degree-of-freedom intelligent electric wrench according to claim 5, characterized in that: The front end of the solid tube (7) is fixedly connected to the heat sink (9) via the heat conducting strip (6).

7. The SMA-driven multi-degree-of-freedom intelligent electric wrench according to claim 5 or 6, characterized in that: The solid tube (7) is a gooseneck tube.

8. The SMA-driven multi-degree-of-freedom intelligent electric wrench according to claim 5 or 6, characterized in that: The SMA spring (12) is connected to the heat conducting strip (6) via the solid tube (7) for heat exchange.

9. The SMA-driven multi-degree-of-freedom intelligent electric wrench according to claim 1, characterized in that: A motor switch (2) for controlling the operation of the motor, and a power switch (3) for controlling the operation of the SMA spring (12) are provided at the rear end of the handle (1).

10. The SMA-driven multi-degree-of-freedom intelligent electric wrench according to claim 1, characterized in that: The heat sink (9) comprises copper heat sinks that are evenly and densely distributed.

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