A temperature-controlled magnetorheological intelligent transmission device based on thermal energy recycling

Abstract

The present invention discloses a temperature-controlled magnetorheological intelligent transmission device based on heat energy recycling, comprising a driving shaft, a driven housing, and a driven shaft. The driven housing comprises a left end cap, a driven cylinder, and a right end cap. The right end of the driving shaft extends into the driven housing to form a transmission section, and the gap between the transmission section and the driven housing is filled with magnetorheological fluid. An excitation coil is wound around each end of the driven cylinder near the transmission section. Several shape memory alloy blades are arranged around the side wall of the transmission section. One side of each shape memory alloy blade is fixedly connected to the transmission section, and the other side is mounted with a friction-resistant metal sheet. A shape memory alloy switch is also provided on the outer side of the driven cylinder. The present invention can effectively reduce the volume of the transmission device while fully utilizing the heat energy generated by the transmission device, effectively controlling the temperature of the transmission device within a suitable range, and improving the stability of the transmission device's torque transmission at different operating temperatures, especially high temperatures.

Description

Technical Field

[0001] The present invention relates to the technical field of power transmission, and in particular to a temperature-controlled magnetorheological intelligent transmission device based on heat energy recycling. Background Art

[0002] Magnetorheological fluids (MRF) and shape memory alloys (SMA) hold great promise for transmission applications due to their unique mechanical properties. Magnetorheological transmission uses a magnetorheological fluid as a transmission medium to transmit torque and speed. Shape memory alloys, a class of alloys that can "remember" their initial shape, hold broad application prospects in transmission control and combined transmissions.

[0003] For example, CN206802225U discloses a shape memory alloy extruded magnetorheological fluid and friction combined transmission device. When the ambient temperature rises, the device can automatically connect to the power supply through the shape memory alloy switch. After the temperature of the device rises, the shape memory alloy spring generates an output force to push the driven pressure plate and the active right housing to generate pressure. The driven pressure plate can also squeeze the magnetorheological fluid, which can increase the performance of the magnetorheological fluid. For example, CN107763109A discloses a "temperature-controlled variable-surface magnetorheological transmission device". The shape memory alloy spring pushes the active plate to change the working surface of the magnetorheological fluid from one to two, which can transmit greater torque, and can automatically adjust the transmitted torque according to the real-time temperature, and ensure the stability of the transmission process. For example, CN212360555 U discloses a multi-disc magnetorheological clutch based on electromagnetic force extrusion. It adopts a multi-disc structure to increase the working area of ​​the magnetorheological fluid, and effectively combines shape memory alloy and magnetorheological fluid into the clutch, effectively solving the problem of magnetorheological fluid performance degradation with increasing ambient temperature. At the same time, it rationally utilizes the extrusion strengthening effect of the magnetorheological fluid to improve the clutch torque.

[0004] The aforementioned research has greatly advanced the field of intelligent MRF transmission. However, most of these studies focused on structural improvements and failed to consider that after a period of transmission, the MRF undergoes continuous shearing, resulting in a continuous increase in temperature due to slip heat generation and heating of the excitation coil. Temperature significantly affects MRF, and excessively high temperatures can significantly degrade the material properties of the MRF, or even render it ineffective. Adding external heat sinks or extrusion devices to the MRF not only complicates the structure but also makes the device bulky. The question is how to utilize the energy generated by slip heat generation and excitation coil heating to compensate for the torque lost during high-temperature rotation. Furthermore, intelligently regulating the amount of heat generated and the on / off switching of the heat source as the temperature rises, achieving intelligent control through temperature, and simplifying the size of the MRF transmission mechanism are crucial for reducing the impact of heat generation on the MRF and force transmission performance. Summary of the Invention

[0005] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to solve the problems of large volume of the existing magnetorheological transmission mechanism, great influence of temperature on performance, and poor torque transmission stability, and to provide a temperature-controlled magnetorheological intelligent transmission device based on heat energy recycling, which can effectively reduce the volume of the transmission device, while making full use of the heat energy generated by the transmission device, and improving the stability of the torque transmission of the transmission device at different operating temperatures, especially high temperatures.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: a temperature-controlled magnetorheological intelligent transmission device based on thermal energy recycling, comprising a driving shaft, a driven housing and a driven shaft, the driven housing comprising a left end cover, a driven cylinder and a right end cover connected in sequence, the right end of the driving shaft passes through the left end cover and extends into the driven housing, and is rotatably connected to the driven housing through a bearing, and the driven shaft is fixedly connected to the right end cover; the part of the driving shaft located in the driven housing is expanded to form a transmission section, and there is a gap between the transmission section and the inner wall of the driven cylinder, and the gap between the transmission section and the driven housing is filled with magnetorheological fluid; it is characterized in that: on the inner side of the driven cylinder, near the two ends of the transmission section, there is respectively provided a coil groove that wraps around the driven cylinder, an excitation coil is respectively wound in the two coil grooves, and the two excitation coils constitute out-of-phase windings; a magnetic isolation ring is provided at the notch of the coil groove, which seals the excitation coil in the coil groove;

[0007] Several shape memory alloy blades are provided on the sidewall of the transmission section and around the transmission section. The width of the shape memory alloy blades is greater than the gap between the transmission section and the driven cylinder. One side of the shape memory alloy blades is fixedly connected to the transmission section, and the other side forms a free side. A friction-resistant metal sheet is installed on the outer side of the free side of the shape memory alloy blades. The cross-section of the shape memory alloy blades is arc-shaped. In the initial state, the shape memory alloy blades are attached to the transmission section, and a gap is formed between the outer side of the shape memory alloy blades and the inner side of the driven cylinder.

[0008] A accommodating groove is also provided on the outside of the driven cylinder, which is located between the two coil grooves. A shape memory alloy switch is provided in the accommodating groove. Both excitation coils are connected to the shape memory alloy switch. The shape memory alloy switch can control the power on and off of the excitation coil and the current size.

[0009] Furthermore, there is an angle between the length direction of the shape memory alloy blade and the axial direction of the driving shaft.

[0010] Furthermore, the shape memory alloy blade is in a diamond shape as a whole, with a long side forming an angle with the axial direction of the driving shaft, and a short side being parallel to both ends of the transmission section.

[0011] Furthermore, a blade groove is provided on the side wall of the transmission section corresponding to each shape memory alloy blade. The shape memory alloy blade is located in the blade groove, and in the initial state, the outer side of the shape memory alloy blade and the side wall of the transmission section are located on the same circumference.

[0012] Furthermore, the shape memory alloy switch includes a shell, a guide rod is provided inside the shell along the length direction of the shell, an insulating rod is slidably connected to the guide rod, a shape memory alloy spring is provided between one side of the insulating rod and one end of the shell, the shape memory alloy spring is connected to the insulating rod and the end of the shell, and can drive the insulating rod to move along the guide rod; a resistance rod is provided on each of the opposite sides of the guide rod, the axis of the resistance rod is parallel to the axis of the guide rod, and one end of the resistance rod away from the shape memory alloy spring is connected to the wiring rod, one end of the wiring rod is connected to the resistance rod, and the other end passes through the shell and is fixedly connected to the shell; a resistance rod is provided at each end of the insulating rod. A variable resistance slider, one end of which is connected to the insulating rod, and the other end extends from the side wall of the shell, and the variable resistance slider is in close contact with the resistance rod; on the side wall of the shell, corresponding to the position of the variable resistance slider, a guide slot is provided along the axial direction of the guide rod, and the end of the variable resistance slider away from the insulating rod extends from the guide slot; in the initial state, the shape memory alloy spring is in an extended state. At this time, the variable resistance slider is in contact with the end of the resistance rod close to the wiring rod, and the effective resistance of the variable resistance rod is the smallest. When the shape memory alloy spring is heated, it gradually contracts and drives the variable resistance slider to move away from the wiring rod, so that the effective resistance of the variable resistance rod gradually increases until the variable resistance slider is separated from the resistance rod.

[0013] Furthermore, a push plate is sleeved on the guide rod and is connected to the guide rod in a sliding manner; the insulating rod is fixedly connected to the push plate, and the shape memory alloy spring is fixedly connected to the push plate.

[0014] Furthermore, a bearing sleeve is provided on the inner side of the driven cylinder, near both ends, and the outer side of the bearing sleeve is fixedly connected to the driven cylinder; the bearing is located on the inner side of the bearing sleeve, and its outer ring is tightly fitted with the inner side of the bearing sleeve; the driving shaft passes through the inner ring of the bearing, and a shaft sleeve is provided between the driving shaft and the inner ring of the bearing.

[0015] Furthermore, a sealing ring is provided between the two ends of the transmission section and the left end cover and the right end cover respectively, and the sealing ring is sleeved on the outside of the driving shaft; the magnetorheological fluid is located in the gap surrounded by the transmission section, the driven housing and the two sealing rings.

[0016] Furthermore, a liquid injection hole is provided on the driven cylinder, which is communicated with the transmission section, the driven housing and the gap formed by the two sealing rings, and a liquid injection screw plug is installed in the liquid injection hole.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. After setting up two excitation coils to form out-of-phase windings, the effective axial working length is effectively increased due to the mutual repulsion between the generated magnetic lines of force. The magnetic induction intensity and its axial distribution uniformity in the working chamber are also significantly enhanced. The magnetic lines of force generated pass vertically through the magnetorheological fluid between the transmission section and the driven cylinder. At the same time, the magnetic particles in the magnetorheological fluid are instantly chained, and their direction is parallel to the direction of the magnetic lines of force. The magnetorheological fluid changes from a Newtonian fluid state to a solid-like state. The whole process takes milliseconds. The active shaft will drive the driven cylinder to rotate. The torque transmitted by the magnetorheological fluid as a medium increases with the increase of the magnetic field intensity. At this time, it is a cylinder-type transmission.

[0019] 2. After the magnetorheological fluid has been working for a period of time, it will generate heat. At the same time, the excitation coil will also dissipate heat after being energized, causing the temperature of the magnetorheological fluid to rise. At this time, the shape memory alloy blade will gradually return to a blade shape after being heated (gradually unfolding from an arc), and its free side will move in the direction away from the transmission section, thereby squeezing the magnetorheological fluid and enhancing the transmitted torque; at the same time, the shape memory alloy spring will gradually shrink after being heated, causing the current of the excitation coil to continuously decrease; when the temperature continues to rise, the performance of the magnetorheological fluid continues to decline. At this time, the friction-resistant metal sheet on the shape memory alloy blade contacts the inner wall of the driven cylinder, and generates friction to provide friction torque, further increasing the torque transmission, thereby ensuring the stability of the torque transmission; at the same time, the shape memory alloy spring continues to shrink until the current is disconnected after the slider leaves the resistance wire, reducing the heat generated by the excitation coil, which helps to restore the performance of the magnetorheological fluid.

[0020] 3. After the current of the excitation coil is disconnected, the heat generated by the excitation coil decreases. At the same time, the magnetorheological fluid returns to liquid state, the heat generated further decreases, and the temperature begins to drop. When the temperature continues to drop, the shape memory alloy spring begins to extend, the slider re-contacts the resistance wire, the current is turned on, and the shape memory alloy sheet also begins to reversely recover. The friction-resistant metal sheet separates from the inner wall of the driven cylinder, but the magnetorheological fluid begins to transmit torque. This reciprocating process effectively controls the temperature of the transmission device within a certain range, keeps the transmitted torque constant and stable, and effectively improves the transmission performance and energy utilization rate of the magnetorheological transmission device. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the present invention.

[0022] Figure 2 for Figure 1 Cross-sectional view along AA direction.

[0023] Figure 3 for Figure 2 Enlarged view of part B in the middle.

[0024] Figure 4 It is a structural schematic diagram of the shape memory alloy switch in the present invention.

[0025] Figure 5 This is a diagram of the state of the shape memory alloy blade after being heated and expanded in the present invention.

[0026] In the figure: 1-driving shaft; 2-driven shaft; 3-left end cover; 4-driven cylinder; 5-right end cover; 6-transmission section; 7-magnetorheological fluid; 8-excitation coil; 9-magnetic isolation ring; 10-shape memory alloy blade; 11-friction-resistant metal sheet; 12-shape memory alloy switch; 121-housing; 122-guide rod; 123-insulating rod; 124-shape memory alloy spring; 125-resistance lever; 126-connecting rod; 127-resistance slider; 128-push plate; 13-bearing sleeve; 14-sealing ring; 15-liquid injection plug. DETAILED DESCRIPTION

[0027] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0028] Example: See Figure 1 — Figure 5A temperature-controlled magnetorheological intelligent transmission device based on thermal energy reuse comprises a driving shaft 1, a driven housing, and a driven shaft 2. The driven housing comprises a left end cap 3, a driven cylinder 4, and a right end cap 5, which are connected in sequence. The right end of the driving shaft 1 passes through the left end cap 3 and extends into the driven housing. It is rotatably connected to the driven housing via a bearing. A rubber ring is also provided between the driving shaft 1 and the left end cap 3. In actual processing, a bearing sleeve 13 is provided on the inner side of the driven cylinder 4, near both ends. The outer side of the bearing sleeve 13 is fixedly connected to the driven cylinder 4 (via bolts). The left end cap 3 and the right end cap 5 are respectively fixedly connected to the adjacent bearing sleeve 13 (via bolts). The bearing is located inside the bearing sleeve 13, and its outer ring is tightly fitted with the inner side of the bearing sleeve 13. The driving shaft 1 passes through the inner ring of the bearing, and a sleeve is provided between the driving shaft 1 and the inner ring of the bearing. The inner ring of the bearing is fastened to the driving shaft 1 via the sleeve. The driven shaft 2 is fixedly connected to the right end cap 5; during processing, the driven shaft 2 and the right end cap 5 are integrally formed. The portion of the driving shaft 1 located within the driven housing is expanded to form a transmission section 6, with a gap between the transmission section 6 and the inner wall of the driven cylinder 4. This gap is filled with magnetorheological fluid 7. A sealing ring 14 is provided between each end of the transmission section 6 and the left and right end caps 3 and 5, respectively. The sealing rings 14 are fitted around the outside of the driving shaft 1. The magnetorheological fluid is located within the gap formed by the transmission section 6, the driven housing, and the two sealing rings 14. The provision of the sealing ring 14 effectively confines the magnetorheological fluid 7 within an annular cylindrical space and prevents leakage. The driven cylinder 4 is also provided with an injection hole, which communicates with the transmission section 6, the driven housing, and the gap formed by the two sealing rings 14. An injection screw 15 is fitted within the injection hole.

[0029] Inside the driven cylinder 4, near each end of the transmission section 6, are two coil slots that wrap around the driven cylinder 4. An excitation coil 8 is wound in each of the two coil slots, and the two excitation coils 8 (wound in opposite directions) form an out-of-phase winding. A magnetic isolation ring 9 is provided at the notch of the coil slot, enclosing the excitation coil 8 within the coil slot. The excitation coils 8 form an out-of-phase winding, and the magnetic lines of force generated by them repel each other, effectively increasing the effective axial working length and significantly enhancing the magnetic induction intensity and its uniformity of distribution in the axial direction of the working chamber.

[0030] Several shape-memory alloy blades 10 are arranged around the sidewall of the transmission section 6. In practical implementation, twelve are preferably present, evenly distributed around the transmission section 6. The width of each shape-memory alloy blade 10 is greater than the gap between the transmission section 6 and the driven cylinder 4. One side of each blade is fixedly connected to the transmission section 6 via rivets, while the other side is free. As an optimization, the corresponding side of the shape-memory alloy blade 10 is fixedly connected to the transmission section 6. A friction-resistant metal sheet 11 is rivet-mounted on the outer side of the free side of the shape-memory alloy blade 10 (the side facing away from the transmission section 6). Among them, the cross-section of the shape memory alloy blade 10 is arc-shaped. In the initial state, the shape memory alloy blade 10 is attached to the transmission section 6, and there is a gap between the outer side of the shape memory alloy blade 10 and the inner side of the driven cylinder 4; when the shape memory alloy blade 10 is heated, it can gradually unfold (that is, the curvature of the cross-section of the shape memory alloy blade 10 gradually becomes smaller), and the free side of the shape memory alloy blade 10 moves away from the transmission section 6, and can make the friction-resistant metal sheet 11 fit the inner wall of the driven cylinder 4.

[0031] During specific implementation, the length direction of the shape memory alloy blade 10 forms an angle with the axial direction of the driving shaft 1. As an optimization, the shape memory alloy blade 10 is in the shape of a rhombus as a whole, with its long side forming an angle with the axial direction of the driving shaft 1, and its short side being parallel to both ends of the transmission section 6. In this way, when the shape memory alloy blade 10 returns to a planar shape after being heated, it can separate the gap between the transmission section 6 and the driven cylinder 4 into a number of wedge-shaped spaces, thereby forming a wedge-shaped extrusion on the magnetorheological fluid 7, which can effectively improve the performance and torque transmission effect of the magnetorheological fluid 7. During installation, a blade groove is provided on the side wall of the transmission section 6 corresponding to each shape memory alloy blade 10, and the shape memory alloy blade 10 is located in the blade groove, and in the initial state, the outer side of the shape memory alloy blade 10 is located on the same circumference as the side wall of the transmission section 6.

[0032] A receiving groove is also provided on the outside of the driven cylinder 4, which is located between the two coil grooves. A shape memory alloy switch 12 is provided in the receiving groove. Both excitation coils 8 are connected to the shape memory alloy switch 12. The shape memory alloy switch 12 can control the power on and off of the excitation coils 8 and the current size. The shape memory alloy switch 12 includes a cylindrical shell 121, and a guide rod 122 is provided inside the shell 121 along the length direction (axial direction) of the shell 121. The two ends of the guide rod 122 are fixedly connected to the two ends of the shell 121 respectively. An insulating rod 123 is slidably connected to the guide rod 122, and a shape memory alloy spring 124 is provided between one side of the insulating rod 123 and one end of the shell 121. The shape memory alloy spring 124 is sleeved on the guide rod 122 and connected to the ends of the insulating rod 123 and the shell 121, and can drive the insulating rod 123 to move along the guide rod 122. In a specific implementation, a push plate 128 is sleeved on the guide rod 122 and is slidably connected to the guide rod 122. The insulating rod 123 is fixedly connected to the push plate 128, and the shape memory alloy spring 124 is fixedly connected to the push plate 128. In this way, the stability of the movement of the insulating rod 123 driven by the shape memory alloy spring 124 can be ensured.

[0033] A resistor rod is provided on opposite sides of the guide rod 122. Its axis is parallel to that of the guide rod 122, and its end facing away from the shape-memory alloy spring 124 is connected to a (metal) connecting rod 126. One end of the connecting rod 126 is connected to the resistor rod, while the other end extends through and is fixedly connected to the end of the housing 121, forming a first terminal. The end of the resistor rod adjacent to the shape-memory alloy spring 124 is free, and a gap exists between the ends adjacent to the housing 121. A variable resistance slider 127 is provided at each end of the insulating rod 123. One end of the variable resistance slider 127 is connected to the insulating rod 123, while the other end extends from the sidewall of the housing 121, closely abutting the resistor rod. A guide slot is provided on the sidewall of the housing 121, corresponding to the position of the variable resistance slider 127, along the axial direction of the guide rod 122. The end of the variable resistance slider 127 facing away from the insulating rod 123 extends from this guide slot, forming a second terminal. In the initial state, shape memory alloy spring 124 is in an extended state. At this point, variable resistance slider 127 contacts the end of the resistor rod closest to connection rod 126, and the effective resistance of variable resistance rod 125 is minimal. When shape memory alloy spring 124 is heated, it gradually contracts, driving variable resistance slider 127 away from connection rod 126, gradually increasing the effective resistance of variable resistance rod 125 until variable resistance slider 127 separates from the resistor rod. In practice, the free end of the resistor rod is tapered. This tapered end provides better guidance for variable resistance slider 127 during re-engagement with the resistor rod, preventing interference with the resistor rod and ensuring stable contact between variable resistance slider 127 and the resistor rod.

[0034] During actual assembly, a brush slip ring is also installed on the driven cylinder 4. One end of the two excitation coils 8 is connected to the two variable resistance sliders 127, and the other end is directly connected to the brush slip ring. The two connecting rods 126 are also connected to the brush slip ring, thereby supplying power to the two excitation coils 8. To further improve heat utilization efficiency, the end of the housing 121 near the shape memory alloy spring 124 is fixedly connected to the bottom of the accommodating groove.

[0035] In this solution, the shape memory alloy blade 10 and the shape memory alloy spring 124 are both made of shape memory alloy with a two-way memory effect, thereby enabling intelligent control and ensuring stable torque transmission.

[0036] The torque transmitted when the shape memory alloy blade fits the transmission section is:

[0037]

[0038] Where, L is the actual axial length of the magnetorheological fluid; L eis the effective axial length of the magnetorheological fluid that can produce the magnetorheological fluid effect; R2 is the distance from the inner wall of the driven cylinder to the axis of the driving shaft; R3 is the distance from the outer surface of the shape memory alloy blade to the axis of the driving shaft when it is attached to the driving shaft; τ y (H) is the yield stress of the fluid; η is the fluid viscosity; a is the ratio of the surface area of ​​the shape memory alloy blade when it is attached to the driving shaft to the surface of the transmission shaft

[0039] The friction torque generated between the friction-resistant metal sheet and the driven cylinder after the shape memory alloy blade returns to normal is:

[0040] T2=s s 1.155(R2-R1)Smln d / R

[0041] Where s s is the yield limit of the shape memory alloy; R1 is the distance from the driving shaft transmission surface to the driving shaft axis; R2 is the distance from the inner wall of the driven cylinder to the driving shaft axis; S is the friction contact area; m is the friction coefficient; d is the thickness of the shape memory alloy sheet; R is the radius of the outer surface of the curved part of the shape memory alloy blade when it is attached to the driving shaft.

[0042] During operation: the driving shaft of the transmission device is connected to the power source (device) through a key or coupling. When the power source (device) drives the driving shaft to rotate, the power is transmitted to the magnetorheological fluid:

[0043] 1. When the excitation coil is not energized, no electromagnetic field is generated, and the magnetorheological fluid between the driving shaft and the driven cylinder exhibits the characteristics of a low-viscosity Newtonian fluid, and the transmitted torque is very small or almost no torque is transmitted.

[0044] 2. After the excitation coil is powered on, it starts to generate an electromagnetic field. The magnetic lines of force generated by it pass vertically through the magnetorheological fluid between the active shaft and the driven cylinder. At the same time, the magnetic particles in the magnetorheological fluid are instantly chained, and their direction is parallel to the direction of the magnetic lines of force. The magnetorheological fluid changes from a Newtonian fluid state to a solid-like state. The whole process takes milliseconds. The active shaft will drive the driven part to rotate. The torque transmitted by the magnetorheological fluid as a medium increases with the increase of the magnetic field strength (input current); when the temperature is low, the shape memory alloy blades on the transmission section fit the active shaft, and the torque is transmitted only by the chained magnetorheological fluid, forming a cylinder transmission.

[0045] 3. After a period of torque transmission, the magnetorheological fluid is constantly sheared, and the slip heat and the heating of the excitation coil will increase the temperature of the magnetorheological fluid. Excessive temperature will significantly reduce the material properties of the magnetorheological fluid. When the temperature rises (such as reaching 70°C), the shape memory alloy blades gradually return to the blade shape (unfold). During the recovery process, the magnetorheological fluid is wedge-extended and strengthened, and the working gap generates fluid dynamic pressure, which causes the magnetic particles to impact and shear the inner wall of the driven cylinder, thereby improving the transmission capacity and enhancing the transmitted torque. At the same time, the shape memory alloy spring of the shape memory alloy switch gradually recovers and contracts, and the effective resistance of the resistance rod (the resistance connected to the circuit) gradually increases, which continuously reduces the current of the excitation coil, thereby reducing the heating of the excitation coil and improving the performance of the magnetorheological fluid, thereby ensuring the overall stability of the transmission device.

[0046] 4. After the temperature continues to rise (such as reaching 100°C), the friction-resistant metal sheet on the shape memory alloy blade contacts the inner wall of the driven cylinder and generates friction, providing transmission torque; and the shape memory alloy spring continues to recover and shrink until the variable resistance slide is separated from the resistance rod, the current is disconnected, the magnetorheological fluid returns to liquid state, no longer transmits torque, the excitation coil and the magnetorheological fluid no longer generate heat, and the transmission device as a whole begins to cool down; but at this time, the torque is transmitted by relying on the hard friction between the friction-resistant metal sheet on the shape memory alloy sheet and the inner wall of the driven cylinder to ensure the overall stability of the transmission device.

[0047] 5. After the current is disconnected, the temperature begins to drop, the shape memory alloy blades begin to reverse recovery (move toward the transmission section), the friction-resistant metal sheet separates from the inner wall of the driven cylinder, and no longer transmits friction torque; but at this time, the shape memory alloy spring also begins to reverse recovery (elongation), the variable resistance slider re-contacts the resistance rod, the current is reconnected, and the magnetorheological fluid begins to transmit torque; this reciprocating process automatically controls the temperature of the transmission device during operation within a certain range, keeps the transmitted torque constant and stable, and at the same time effectively improves the transmission performance and energy utilization efficiency of the magnetorheological transmission device.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the technical solutions. Those skilled in the art should understand that modifications or equivalent replacements of the technical solutions of the present invention that do not depart from the purpose and scope of the technical solutions of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A temperature-controlled magnetorheological intelligent transmission device based on thermal energy recycling, comprising a driving shaft, a driven housing, and a driven shaft. The driven housing comprises a left end cap, a driven cylinder, and a right end cap connected in sequence. The right end of the driving shaft passes through the left end cap and extends into the driven housing, where it is rotationally connected to the driven housing via a bearing. The driven shaft is fixedly connected to the right end cap. The portion of the driving shaft located within the driven housing is expanded to form a transmission section, and a gap is defined between the transmission section and the inner wall of the driven cylinder. The gap between the transmission section and the driven housing is filled with magnetorheological fluid. The device is characterized by: On the inner side of the driven cylinder, near both ends of the transmission section, there are two coil slots that wrap around the driven cylinder. An excitation coil is wound in each of the two coil slots, and the two excitation coils form an out-of-phase winding. A magnetic isolation ring is provided at the notch of the coil slot to seal the excitation coil in the coil slot. Several shape memory alloy blades are provided on the sidewall of the transmission section and around the transmission section. The width of the shape memory alloy blades is greater than the gap between the transmission section and the driven cylinder. One side of the shape memory alloy blades is fixedly connected to the transmission section, and the other side forms a free side. A friction-resistant metal sheet is installed on the outer side of the free side of the shape memory alloy blades. The cross-section of the shape memory alloy blades is arc-shaped. In the initial state, the shape memory alloy blades are attached to the transmission section, and a gap is formed between the outer side of the shape memory alloy blades and the inner side of the driven cylinder. A receiving groove is also provided on the outside of the driven cylinder. The receiving groove is located between the two coil grooves. A shape memory alloy switch is provided in the receiving groove. Both excitation coils are connected to the shape memory alloy switch. The shape memory alloy switch can control the power on and off of the excitation coils and the current size. The shape memory alloy switch includes a shell, a guide rod is provided in the shell along the length direction of the shell, an insulating rod is slidably connected to the guide rod, a shape memory alloy spring is provided between one side of the insulating rod and one end of the shell, the shape memory alloy spring is connected to the insulating rod and the end of the shell, and can drive the insulating rod to move along the guide rod; a resistance rod is provided on each of the opposite sides of the guide rod, the axis of the resistance rod is parallel to the axis of the guide rod, and the end away from the shape memory alloy spring is connected to the wiring rod, one end of the wiring rod is connected to the resistance rod, and the other end passes through the shell and is fixedly connected to the shell; a variable resistance sliding rod is provided at each end of the insulating rod. The variable resistance slider has one end connected to the insulating rod and the other end extending from the side wall of the housing, and the variable resistance slider is in close contact with the resistance rod; on the side wall of the housing, corresponding to the position of the variable resistance slider, a guide slot is provided along the axial direction of the guide rod, and the end of the variable resistance slider away from the insulating rod extends from the guide slot; in the initial state, the shape memory alloy spring is in an extended state. At this time, the variable resistance slider is in contact with the end of the resistance rod close to the wiring rod, and the effective resistance of the variable resistance rod is the smallest. When the shape memory alloy spring is heated, it gradually contracts and drives the variable resistance slider to move away from the wiring rod, so that the effective resistance of the variable resistance rod gradually increases until the variable resistance slider is separated from the resistance rod.

2. The temperature-controlled magnetorheological intelligent transmission device based on heat energy recycling according to claim 1, characterized in that: An included angle is formed between the length direction of the shape memory alloy blade and the axial direction of the driving shaft.

3. The temperature-controlled magnetorheological intelligent transmission device based on heat energy recycling according to claim 2, characterized in that: The shape memory alloy blade is in a rhombus shape as a whole, with an angle between its long side and the axial direction of the driving shaft, and a short side parallel to the two ends of the transmission section.

4. The temperature-controlled magnetorheological intelligent transmission device based on heat energy recycling according to claim 1, characterized in that: A blade groove is provided on the side wall of the transmission section corresponding to each shape memory alloy blade. The shape memory alloy blade is located in the blade groove. In the initial state, the outer side of the shape memory alloy blade and the side wall of the transmission section are located on the same circumference.

5. The temperature-controlled magnetorheological intelligent transmission device based on heat energy recycling according to claim 1, characterized in that: A push plate is sleeved on the guide rod and is connected to the guide rod in a sliding manner. The insulating rod is fixedly connected to the push plate, and the shape memory alloy spring is fixedly connected to the push plate.

6. The temperature-controlled magnetorheological intelligent transmission device based on heat energy recycling according to claim 1, characterized in that: A bearing sleeve is provided on the inner side of the driven cylinder, near both ends. The outer side of the bearing sleeve is fixedly connected to the driven cylinder. The bearing is located on the inner side of the bearing sleeve, and its outer ring is tightly fitted with the inner side of the bearing sleeve. The driving shaft passes through the inner ring of the bearing, and a shaft sleeve is provided between the driving shaft and the inner ring of the bearing.

7. The temperature-controlled magnetorheological intelligent transmission device based on heat energy recycling according to claim 1, characterized in that: A sealing ring is provided between the two ends of the transmission section and the left end cover and the right end cover respectively. The sealing ring is sleeved on the outside of the driving shaft; the magnetorheological fluid is located in the gap surrounded by the transmission section, the driven housing and the two sealing rings.

8. The temperature-controlled magnetorheological intelligent transmission device based on heat energy recycling according to claim 7, characterized in that: A liquid injection hole is also provided on the driven cylinder, which is communicated with the transmission section, the driven housing and the gap surrounded by the two sealing rings. A liquid injection screw plug is installed in the liquid injection hole.

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