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CN-116428142-B - SMA wire driven rotary driver

CN116428142BCN 116428142 BCN116428142 BCN 116428142BCN-116428142-B

Abstract

The invention provides a rotary driver driven by an SMA wire, wherein square head sections at two ends of an output shaft are connected with fixed ends, a torsion disc and a driving disc are arranged on a round shaft section at the middle part, the driving disc is fixedly connected with the output shaft, and a torsion disc is supported on the output shaft through a bearing. The SMA wires pass through the axial round holes on the torque transmission disc and the driving disc to be arranged in a turn-back way or in parallel way, and the outer edge of the torque transmission disc is fixedly connected with the driving end through the torque transmission shell so as to output torque. When the external load acts, the torque transmission shell rotates relative to the output shaft, the torque transmission disc rotates relative to the driving disc, the driver keeps balance under the action of the external load and the tensile force of the SMA wire, when the driving is needed, the SMA wire is electrified and heated to enable the SMA wire to generate phase change deformation and shrink, the torque transmission disc is driven to rotate, and therefore relative rotation of the driving end and the fixed end is achieved. The invention has simple structure, small radial size, large output torque and high driving efficiency.

Inventors

  • Request for anonymity
  • FU JIALI

Assignees

  • 北京灵翼航宇科技有限公司

Dates

Publication Date
20260512
Application Date
20230309

Claims (10)

  1. 1. The SMA wire driven rotary driver comprises an output shaft (1), a torque transmission shell (2), an SMA wire (4), a left torsion disc (5), a driving disc (6), a right torsion disc (7) and a bearing (8), and is characterized in that, The output shaft (1) and the torque transmission discs (5, 7) are connecting pieces, two ends of the output shaft (1) are connected with fixed ends, the left torque transmission disc (5) and the right torque transmission disc (7) are supported by two ends of a middle circular shaft section through bearings (8) respectively, the middle of the circular shaft section of the output shaft (1) is fixedly connected with a driving disc (6), the outer edges of the torque transmission discs (5, 7) are fixedly connected with a torque transmission shell (2), and the driving ends are connected with the outside of the torque transmission shell (2), and axial round holes penetrating through SMA wires (4) are arranged on the circumferences of the torque transmission discs (5, 7) and the driving disc (6); The SMA wire (4) is a driving element and axially passes through axial round holes on the left torque transmission disc (5), the driving disc (6) and the right torque transmission disc (7); When the external load acts, the torque transmission shell (2) rotates relative to the output shaft (1), the left torque transmission disc (5) and the right torque transmission disc (7) correspondingly rotate relative to the driving disc (6), the whole driver is balanced under the action of the external load and the tension of the SMA wire (4), when the driving is needed, the SMA wire (4) is electrified and heated to be deformed in a phase change mode to shrink, the torque transmission discs (5, 7) are driven to rotate, so that the relative rotation of the driving end and the fixed end is realized, after the driving is finished, the power supply to the SMA wire (4) is stopped, the temperature of the SMA wire (4) is reduced, and the driver returns to a state before the driving under the action of the external load.
  2. 2. A SMA wire driven rotary actuator according to claim 1, characterized in that the part of the output shaft (1) where both ends are connected to the fixed end is a square head section.
  3. 3. The SMA wire driven rotary driver according to claim 1, characterized in that the output shaft (1) is provided with 6 annular grooves, the positions of the grooves respectively correspond to the front and rear edges of the left torque transmission disc (5), the right torque transmission disc (7) and the driving disc (6), and snap spring retainer rings (9) are fixed in the grooves and used for axially limiting the torque transmission discs (5, 7) and the driving disc (6).
  4. 4. A SMA wire driven rotary actuator according to claim 3, characterized in that the drive disc (6) is keyed to the output shaft (1), the drive disc (6) being locked to the output shaft (1) circumferentially.
  5. 5. A SMA wire driven rotary actuator according to claim 1, characterized in that the bearing (8) is a rolling bearing or a sliding bearing.
  6. 6. The SMA wire driven rotary driver according to any one of claims 1 to 5, further comprising an end cap (3), the end cap (3) being connected to two ends of the torque transmission housing (2), the end cap (3) being provided with an axial small hole, and a wire for supplying power to the SMA wire (4) being inserted into the hole.
  7. 7. The SMA wire driven rotary actuator of claim 1, characterized in that the torsion transmission discs (5, 7) and the drive disc (6) are each provided with an insulating tube (11) in an axial circular hole, the SMA wire (4) being arranged through the insulating tube (11).
  8. 8. A SMA wire driven rotary actuator according to claim 1 or 7, characterized in that the part of the SMA wire (4) between the torque transmission disc (5, 7) and the drive disc (6) is sheathed with a heat shrink tube to electrically insulate the whole length of SMA wire (4) from the metallic structural members in the actuator.
  9. 9. The SMA wire driven rotary driver according to claim 1, wherein the SMA wire (4) is arranged in a way of one wire turning back arrangement or a plurality of wires are arranged in parallel, when the turning back arrangement is adopted, the SMA wire (4) passes through the insulating elbow pipe (12) at the turning back position to be arranged, and when the parallel arrangement is adopted, the SMA wires (4) are arranged in parallel to be driven simultaneously.
  10. 10. A SMA wire driven rotary actuator according to claim 7 or 9, characterized in that the insulating tube (11) and insulating elbow tube (12) are both made of ceramic material.

Description

SMA wire driven rotary driver Technical Field The invention relates to the technical field of spacecraft driving devices, in particular to a rotary driving device. Background As a power source for realizing mechanical motion, rotary drives are widely used in a variety of fields such as machinery, electronics, chemical industry, and the like. The rotary driver applied to the fields of airplanes, automobiles, robots, spacecrafts and the like is different from the conventional driver, and the rotary driver is required to meet the following requirements that (1) the working stroke of the driver is limited, and the driver only needs to rotate by a limited angle during driving, (2) the driver is highly miniaturized and integrated, has small volume, light weight, high power density and controllable cost, and (3) the driver has large output torque, the output force arm of the miniaturized driver is short, and the driver is required to output larger torque during driving a load. At present, rotary drivers are widely used on spacecrafts, and the rotary drivers driven by SMA are the most typical types, wherein the SMA drivers with large torque mainly comprise two types, namely, an SMA tube is adopted as a driving element, the driving stroke of the type of drivers is smaller, the structure is complex, and the other type of drivers are driven by an SMA wire-spring, the output stroke of the type of drivers is larger, but the output torque is smaller, and the use is limited. Disclosure of Invention The invention provides a rotary driver driven by an SMA wire, which has the advantages of simple structure, small radial size and large output torque, and aims to solve the technical defects of the conventional rotary driver. The technical scheme adopted by the invention is that the SMA wire driven rotary driver mainly comprises an SMA wire, an output shaft, a left torque transmission disc, a right torque transmission disc, a driving disc, a torque transmission shell and a bearing. Wherein, the SMA wire is a driving element, and the output shaft and the two torque transmission discs are connecting pieces. The output shaft has two ends connected to the fixed end, the middle circular shaft section has two right and left torque transmitting discs supported via bearings and with the same structure, annular center matched with the bearings, and several axially circular holes with SMA wires distributed homogeneously around the torque transmitting discs, outer torque transmitting disc connected to the torque transmitting casing and driving end. The middle of the round shaft section of the output shaft is fixedly connected with a driving disc, and an axial round hole corresponding to the axial round hole of the torque transmission disc is arranged on the circumference of the driving disc. The SMA wire sequentially penetrates through axial round holes in the left torque transmission disc, the driving disc and the right torque transmission disc along the axial direction, and two ends of the wire are fixed on the outer sides of the left torque transmission disc or the right torque transmission disc. When the external load acts, the torque transmission shell rotates relative to the output shaft, the left torque transmission disc and the right torque transmission disc correspondingly rotate relative to the driving disc by a certain angle, and the whole driver is balanced under the action of the external load and the pulling force of the SMA wire. When the driving is needed, the SMA wire is electrified to enable the temperature of the SMA wire to rise, phase change deformation is carried out to enable the SMA wire to shrink, and the torque transmission disc is driven to rotate, so that the relative rotation of the driving end and the fixing end is realized. After the driving is finished, the power on to the SMA wire is stopped, the temperature of the SMA wire is reduced, and the driver returns to the state before the driving under the action of external load. Further, 6 annular grooves are formed in the output shaft, the positions of the grooves correspond to the front edge and the rear edge of the left torsion transmission disc, the right torsion transmission disc and the driving disc, and limiting structures are fixed in the grooves and used for axially limiting the torsion transmission disc and the driving disc. Further, the driving disc is matched with the output shaft through a key slot, and the driving disc is locked with the output shaft in the circumferential direction. Further, the bearing between the torque transmission disc and the output shaft is a rolling bearing or a sliding bearing, so that the torque transmission disc can rotate freely on the output shaft, and the torque transmission disc and the output shaft can rotate relatively under the action of external load or the pulling force of the SMA wire. Further, one or more radial threaded holes are distributed on the disc edges of the left torque transmission disc and the righ