Inertial rotary actuator with controllable life and adjustable step precision and actuating method

Abstract

The application discloses a controllable life step precision adjustable inertial type rotary actuator and an actuating method, and belongs to the field of mechanical engineering. The actuator comprises a device base, a rotary transmission turntable, a rotary load disc, a load disc mounting screw, a circular arc rhombic ring, a joint bearing, an actuating ring, a pre-tightening plate, a disc spring, a pre-tightening rotary top screw and a shell. The application further discloses an actuating method of the actuator. The actuator has the advantages of simple structure, high life, high precision, low power consumption, controllable life and adjustable step precision.

Description

Technical Field

[0001] This invention relates to an inertial piezoelectric actuator, specifically to an inertial rotary actuator with controllable lifespan and adjustable step accuracy, and an actuation method thereof. Background Technology

[0002] With the continuous development of science and technology, higher requirements have been placed on actuation platforms in important industrial fields such as national defense, aerospace, and machinery manufacturing. The continuous progress of science and technology has led researchers to focus on developing various high-precision actuation devices. Their applications have expanded to aerospace, microelectronics, biomedicine, optics, and other fields. Inertial piezoelectric actuators are a type of drive adjustment device that uses asymmetrical drive signals to form a drive adjustment mechanism through inertial impact motion. They are widely used in high-precision adjustment mechanisms due to their simple structure, low resolution, large stroke, and fast response. High-precision rotary adjustment mechanisms, in particular, have been widely used in astronomical telescope mirror adjustment, high-precision adjustment of space antennas, multi-degree-of-freedom actuators, micro-robot joints, and micro-manipulators, playing an increasingly important role.

[0003] However, inertial piezoelectric actuators achieve drive through the periodic frictional coupling of the transmission device and the friction pair of the actuator. During operation, unavoidable wear occurs on the contact surfaces of the friction pair, altering the actuator's output characteristics, affecting its normal frictional coupling motion, and impacting its service life. This severely affects the lifespan and repeatability of the inertial piezoelectric actuator. Summary of the Invention

[0004] In order to overcome the technical problems existing in the prior art, the present invention aims to provide an inertial rotary actuator and its actuation method based on a simple contact resistance structure, high lifespan, high precision, low power consumption, wear condition real-time evaluation, adjustable stepping accuracy, and controllable lifespan.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] An inertial rotary actuator with controllable lifespan and adjustable stepping accuracy includes a base 1, a rotary transmission turntable 2, a rotary load plate 3, a drive device 5, a spherical bearing 6, an actuator ring 7, a preload plate 8, a disc spring 9, a preload rotating set screw 10, and a housing 11. The rotary transmission turntable 2 is mounted inside the base 1 via a rotating shaft to achieve rotation. The rotary load plate 3, located outside the base 1, is fixedly mounted on the rotating shaft of the rotary transmission turntable 2 and can rotate around its rotating shaft together with the rotary transmission turntable 2. The drive device 5 includes a rhombus ring 5-1, a drive piezoelectric ceramic 5-2, and a spherical mounting shaft 5-3. The rhombus ring 5-1 is connected to the base 1, the drive piezoelectric ceramic 5-2 is embedded in the rhombus ring 5-1, and the spherical mounting shaft 5-3 is coaxially fixedly connected to the upper surface of the rhombus ring 5-1. The spherical bearing 6 is fixedly connected to the spherical mounting shaft 5-3, and the outer layer of the spherical bearing 6... An actuating ring 7 is fixedly connected, allowing the actuating ring 7 to rotate radially. The actuating ring 7 is in contact with the rotary transmission turntable 2 and is positioned eccentrically on the rotary transmission turntable 2. When the actuating ring 7 moves axially, the rotary transmission turntable 2 rotates through frictional coupling with it. A preload plate 8 and a disc spring 9 are mounted above the actuating ring 7. The preload plate 8 includes a preload rotating plate 8-1 and a preload mounting shaft 8-2. The preload rotating plate 8-1 is mounted on the preload mounting shaft 8-2 via a pin, enabling radial rotation. The centers of mass of the preload rotating plate 8-1 and the preload mounting shaft 8-2 are on the same axis as the center of mass of the rhomboid ring 5-1. The outer casing 11 is connected to the preload mounting shaft 8-2 via a mounting groove. One or more preload rotating set screws 10 abut against the disc spring 9 located above the preload rotating plate 8-1, thereby providing preload force.

[0007] This inertial rotary actuator drives the piezoelectric ceramic 5-2 to elongate and shorten, causing periodic frictional coupling motion between the actuator ring 7 and the rotary transmission disk 2, thereby driving the rotary load disk 3 to rotate. During this periodic frictional coupling motion, the contact surface of the friction pair formed between the actuator ring 7 and the rotary transmission disk 2 will wear, affecting the normal frictional coupling motion of the actuator. To address this, a detection circuit monitors the resistance value between the actuator ring 7 and the rotary transmission disk 2 in real time. By measuring the resistance value in real time, the wear condition between the contact surfaces of the friction pair can be monitored. The wear state between the actuator ring 7 and the rotary transmission disk 2 can be adjusted by rotating the preload screw 10. As the wear of the contact surface increases over time, tightening the preload screw 10 causes the preload plate 8-1 to rotate, driving the spherical bearing 6 and the actuator ring 7 to rotate. This changes the contact surface between the actuator ring 7 and the rotary transmission disk 2, and the wear state of the contact surface returns to its original level, thereby improving the repeatability and lifespan of the actuator. This makes the accuracy of the inertial rotary actuator adjustable and its lifespan controllable.

[0008] When the preload rotating set screw 10 drives the actuating ring 7 to deflect in the radial direction, the actuating ring 7 drives the rotary transmission turntable 2 to rotate each time through friction. Due to the existence of the reaction force, the tangential component of the reaction force along the actuating ring 7 will drive the actuating ring 7 to rotate along its axis. Each rotation will change the contact surface of the friction pair, further improving the wear state of the contact surface, improving the repeatability and service life of the actuator, and making the accuracy of the inertial rotary actuator adjustable and the service life controllable.

[0009] Preferably, the rhombic ring 5-1 is an arc-shaped rhombic ring, which has a simple structure and is easy to install and assemble. While having a displacement amplification effect, it also plays a role in protecting the driving piezoelectric ceramic.

[0010] The rotating load disk 3 is fixedly mounted on the rotating shaft of the rotating transmission turntable 2 by load disk mounting screws 4, which facilitates disassembly.

[0011] The method for operating an inertial rotary actuator with controllable lifespan and adjustable stepping accuracy involves the following steps to cause the rotary transmission disc 2 to drive the rotary load disc 3 to produce a clockwise displacement: First, the driving piezoelectric ceramic 5-2 is slowly energized from zero voltage to full-stroke voltage, causing it to slowly extend along its axial direction. This also drives the actuating ring 7 to slowly move along the axial direction. At this time, the rotary transmission disc 2 receives an upward static friction force from the actuating ring 7, which overcomes the downward inertial force. The rotary transmission disc 2 remains relatively stationary due to the actuating ring 7, resulting in an upward displacement. Because the actuating ring 7 is mounted on the rotary transmission disc... The eccentric position of the rotary transmission turntable 2 causes it to rotate clockwise. In the second step, the voltage of the driving piezoelectric ceramic 5-2 is rapidly reduced from its full stroke to zero, causing it to contract rapidly along its axis. This causes the rotary transmission turntable 2 to retract rapidly, resulting in a rapid counter-clockwise rotation. However, due to the large inertia of the rotary transmission turntable 2, the downward displacement is less than the downward displacement of the actuating ring 7, resulting in a counter-clockwise rotation less than the clockwise rotation in the first step. The difference between the rotations in the first and second steps is one clockwise rotation angle. Repeating the first and second steps... Disk 2 rotates continuously clockwise, thereby driving the rotating load disk 3 to rotate continuously clockwise. To make the rotating transmission disk 2 rotate counterclockwise, firstly, the driving piezoelectric ceramic 5-2 is rapidly energized from zero voltage to full-stroke voltage, causing the driving piezoelectric ceramic 5-2 to rapidly extend along its axial direction, driving the rotating transmission disk 2 to rotate rapidly clockwise. At this time, the rotating transmission disk 2 is subjected to upward sliding friction force from the actuating ring 7, but due to its large inertia, the upward displacement of the rotating transmission disk 2 is less than the upward displacement of the actuating ring 7, that is, a small clockwise rotation angle is produced; second ... rotate rapidly along its axial direction, driving the rotating load disk 3 to rotate counterclockwise. The driving voltage of ceramic 5-2 is slowly reduced to zero, causing the piezoelectric ceramic 5-2 to slowly contract axially, which in turn causes the actuating ring 7 to contract slowly. At this time, the downward static friction force of the actuating ring 7 on the rotary transmission turntable 2 can overcome the inertial force, and the rotary transmission turntable 2 and the actuating ring 7 remain relatively stationary, producing a downward displacement. That is, the amount of counterclockwise rotation produced is greater than the amount of clockwise rotation produced in the first step. The difference between the rotation in the first step and the second step is a counterclockwise rotation angle. Repeating the first and second steps, the rotary transmission turntable 2 produces a continuous counterclockwise rotation, thereby driving the rotary load disk 3 to produce a continuous counterclockwise rotation.

[0012] Compared with the prior art, the present invention has the following advantages:

[0013] 1. The inertial rotary actuator with controllable lifespan and adjustable stepping accuracy described in this invention uses piezoelectric ceramics for driving, resulting in high driving accuracy and fast response.

[0014] 2. The inertial rotary actuator with controllable lifespan and adjustable stepping accuracy described in this invention has a simple and compact structure, and is easy to process and install.

[0015] 3. The inertial rotary actuator with controllable lifespan and adjustable stepping accuracy described in this invention can monitor the wear condition between the contact surfaces of the friction pair in real time by monitoring the resistance value between the actuating ring 7 and the rotary transmission turntable 2.

[0016] 4. The inertial rotary actuator with controllable lifespan and adjustable stepping accuracy described in this invention can improve the repeatability and lifespan of the actuator by slowly tightening the preload rotating set screw 10, which changes the contact surface of the friction pair and restores the wear state of the contact surface to its original level. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the actuator of the present invention in an explosion.

[0018] Figure 2 This is a cross-sectional view of the actuator structure of the present invention.

[0019] Figure 3 This is a schematic diagram of the arc-shaped rhomboid ring of the present invention.

[0020] Figure 4 This is a schematic diagram of the pre-tightening rotating plate of the present invention.

[0021] Figure 5 This is a timing diagram of the clockwise motion driving voltage of the present invention.

[0022] Figure 6 This is a timing diagram of the counterclockwise motion driving voltage of the present invention. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0024] like Figure 1 , Figure 2 , Figure 3 and Figure 4As shown, the inertial rotary actuator of the present invention with controllable lifespan and adjustable stepping accuracy includes a device base 1, a rotary transmission turntable 2, a rotary load plate 3, a load plate mounting screw 4, a drive device 5, a spherical bearing 6, an actuator ring 7, a preload plate 8, a disc spring 9, a preload rotating set screw 10, and a housing 11. The rotary transmission turntable 2 is mounted inside the device base 1 via a rotating shaft and can rotate. The rotary load plate 3, located outside the device base 1, is fixedly mounted on the rotating shaft of the rotary transmission turntable 2 via the load plate mounting screw 4 and can rotate together with the rotary transmission turntable 2 around its rotating shaft. The drive device 5 includes a rhombus ring 5-1, a drive piezoelectric ceramic 5-2, and a spherical mounting shaft 5-3. The rhombus ring 5-1 is connected to the device base 1 by screws. The drive piezoelectric ceramic 5-2 is embedded inside the rhombus ring 5-1, and the spherical mounting shaft 5-3 is fixedly connected to the upper surface of the rhombus ring 5-1. The axes of the rhombus ring 5-1 and the spherical mounting shaft 5-3 are on the same straight line. A spherical bearing 6 is fixedly connected to a spherical mounting shaft 5-3, and an actuating ring 7 is fixedly connected to the outer layer of the spherical bearing 6, allowing the actuating ring 7 to rotate radially. The actuating ring 7 is in contact with the rotary transmission disk 2 and is positioned eccentrically on the rotary transmission disk 2. When the actuating ring 7 moves axially, the rotary transmission disk 2 rotates through frictional coupling with it. A preload plate 8 and a disc spring 9 are mounted above the actuating ring 7. The preload plate 8 includes a preload rotating plate 8-1 and a preload mounting shaft 8-2. The preload rotating plate 8-1 is mounted on the preload mounting shaft 8-2 via a pin, allowing radial rotation. The centers of mass of both plates and the center of mass of the arc-shaped rhomboid ring 5-1 are on the same axis. The outer casing 11 is connected to the preload mounting shaft 8-2 via a mounting groove. Two preload rotating set screws 10 abut against the disc spring 9 located above the preload rotating plate 8-1, providing preload force.

[0025] This inertial rotary actuator drives the piezoelectric ceramic 5-2 to elongate and shorten, causing periodic frictional coupling motion between the actuating ring 7 and the rotary transmission disk 2. This, in turn, drives the rotating load disk 3 to rotate. During this periodic frictional coupling motion, the contact surfaces of the friction pair formed by the actuating ring 7 and the rotary transmission disk 2 inevitably experience wear, affecting the normal frictional coupling motion of the actuator. To address this, the inertial rotary actuator uses a detection circuit to monitor the resistance value between the actuating ring 7 and the rotary transmission disk 2 in real time. By measuring the resistance value in real time, the wear condition between the contact surfaces of the friction pair can be monitored. The wear state between the actuator ring 7 and the rotary transmission turntable 2 can be adjusted by rotating the preload rotating set screw 10. As the wear of the contact surface increases over time, the preload rotating plate 8-1 is rotated by slowly tightening the preload rotating set screw 10, which drives the spherical bearing 6 and the actuator ring 7 to rotate. This causes a change in the contact surface between the actuator ring 7 and the rotary transmission turntable 2, and the wear state of the contact surface returns to the original level. This improves the repeatability and life of the actuator, making the accuracy of the inertial rotary actuator adjustable and its life controllable.

[0026] On the other hand, when the preload rotating set screw 10 drives the actuating ring 7 to deflect radially, each time the actuating ring 7 drives the rotary transmission disc 2 to rotate through friction, the tangential component of the reaction force along the actuating ring 7 will cause the actuating ring 7 to rotate along its axis due to the presence of the reaction force. Each rotation will change the contact surface of the friction pair, further improving the wear condition of the contact surface, greatly improving the repeatability and service life of the actuator, making the accuracy of this inertial rotary actuator adjustable and its lifespan controllable.

[0027] The specific method for achieving the actuation is as follows: To cause the rotating transmission turntable 2 to drive the rotating load disc 3 to produce a clockwise displacement, such as... Figure 5As shown, in the first step, the driving piezoelectric ceramic 5-2 is slowly energized from zero voltage to full stroke voltage, causing the driving piezoelectric ceramic 5-2 to slowly extend along its axial direction. Similarly, the actuating ring 7 is slowly moved along the axial direction. At this time, the rotating transmission disk 2 is provided with an upward static friction force by the actuating ring 7, which can overcome the downward inertial force. The rotating transmission disk 2 is kept relatively stationary by the actuating ring 7, and an upward displacement is generated. Since the actuating ring 7 is set at the eccentric position of the rotating transmission disk 2, the rotating transmission disk 2 will rotate clockwise at this time. The second step involves rapidly reducing the voltage of the driving piezoelectric ceramic 5-2 from its full stroke to zero. This causes the piezoelectric ceramic 5-2 to rapidly retract along its axial direction, driving the rotary transmission disk 2 to retract quickly, thus rapidly generating a counter-clockwise rotation. However, due to the large inertia of the rotary transmission disk 2, the downward displacement is less than the downward displacement of the actuating ring 7, resulting in a counter-clockwise rotation less than the clockwise rotation in the first step. The difference between the rotations in the first and second steps is one clockwise rotation angle. Repeating the first and second steps, the rotary transmission disk 2 generates a continuous clockwise rotation, thereby driving the rotary load disk 3 to generate a continuous clockwise rotation. Similarly, to generate a counter-clockwise displacement in the rotary transmission disk 2, as... Figure 6 As shown, in the first step, the driving piezoelectric ceramic 5-2 is rapidly energized from zero voltage to full stroke voltage, causing the driving piezoelectric ceramic 5-2 to rapidly extend along its axial direction, driving the rotary transmission disk 2 to rotate rapidly clockwise. At this time, the rotary transmission disk 2 is subjected to an upward sliding friction force from the actuating ring 7. However, due to its large inertia, the upward displacement of the rotary transmission disk 2 is less than the upward displacement of the actuating ring 7, that is, a small clockwise rotation angle is generated. In the second step, the driving voltage of the piezoelectric ceramic 5-2 is slowly reduced to zero. The piezoelectric ceramic 5-2 slowly contracts along the axial direction, causing the actuating ring 7 to contract slowly. At this time, the downward static friction force of the actuating ring 7 on the rotary transmission turntable 2 can overcome the inertial force. The rotary transmission turntable 2 and the actuating ring 7 remain relatively stationary, producing a downward displacement. That is, the amount of counterclockwise rotation produced is greater than the amount of clockwise rotation produced in the first step. The difference between the rotation in the first step and the second step is a counterclockwise rotation angle. By repeating the first and second steps, the rotary transmission turntable 2 produces a continuous counterclockwise rotation, thereby driving the rotary load disk 3 to produce a continuous counterclockwise rotation.

Claims

1. An inertial rotary actuator with controllable lifespan and adjustable stepping accuracy, characterized in that: The device includes a base (1), a rotary transmission turntable (2), a rotary load plate (3), a drive device (5), a spherical bearing (6), an actuating ring (7), a preload plate (8), a disc spring (9), a preload rotating set screw (10), and a housing (11). The rotary transmission turntable (2) is installed inside the device base (1) via a rotating shaft to achieve rotation. The rotary load plate (3) on the outside of the device base (1) is fixedly installed on the rotating shaft of the rotary transmission turntable (2) and can rotate together with the rotary transmission turntable (2) around its rotating shaft. The drive device (5) includes a rhombus ring (5-1), a drive piezoelectric ceramic (5-2), and a spherical mounting shaft (5-3). The rhombus ring (5-1) is connected to the device base (1). The drive piezoelectric ceramic (5-2) is embedded in the rhombus ring (5-1). The spherical mounting shaft (5-3) is coaxially fixedly connected to the upper surface of the rhombus ring (5-1). The spherical bearing (6) is fixedly connected to the spherical mounting shaft (5-3). The outer layer of the spherical bearing (6) is fixedly connected to the actuating ring (7), so that the actuating ring (7) can rotate around the radial direction. At the same time, the actuating ring (7) is in contact with the rotary transmission turntable (2) and is set at an eccentric position on the rotary transmission turntable (2). When the actuating ring (7) moves along the axial direction, it rotates with the rotary transmission turntable (2). The frictional coupling between the rotary transmission turntable (2) enables the rotary transmission turntable (2) to rotate; a preload plate (8) and a disc spring (9) are installed above the actuating ring (7). The preload plate (8) includes a preload rotating plate (8-1) and a preload mounting shaft (8-2). The preload rotating plate (8-1) is mounted on the preload mounting shaft (8-2) by a pin to achieve rotation in the radial direction. The center of mass of the preload rotating plate (8-1) and the preload mounting shaft (8-2) is on the same axis as the center of mass of the rhomboid ring (5-1). The outer shell (11) is connected to the preload mounting shaft (8-2) through the mounting groove. One or more preload rotating set screws (10) abut against the disc spring (9) located above the preload rotating plate (8-1) to provide preload force.

2. The inertial rotary actuator with controllable lifespan and adjustable stepping accuracy according to claim 1, characterized in that: This inertial rotary actuator drives the piezoelectric ceramic (5-2) to elongate and shorten, causing periodic frictional coupling motion between the actuator ring (7) and the rotary transmission disk (2), thereby driving the rotary load disk (3) to rotate. During this periodic frictional coupling motion, the contact surface of the friction pair formed between the actuator ring (7) and the rotary transmission disk (2) will wear, affecting the normal frictional coupling motion of the actuator. Therefore, the resistance value between the actuator ring (7) and the rotary transmission disk (2) is monitored in real time by a detection circuit. By measuring the resistance value in real time, the contact of the friction pair can be monitored in real time. The wear condition between surfaces; and by rotating the preload rotating set screw (10), the wear condition between the actuator ring (7) and the rotary transmission turntable (2) can be adjusted. As time goes by, the wear of the contact surface increases. By tightening the preload rotating set screw (10), the preload rotating plate (8-1) is rotated, which drives the joint bearing (6) and the actuator ring (7) to rotate, thereby changing the contact surface between the actuator ring (7) and the rotary transmission turntable (2). At this time, the wear condition of the contact surface returns to the original level, thereby improving the repeatability and life of the actuator, making the accuracy of the inertial rotary actuator adjustable and the life controllable.

3. The inertial rotary actuator with controllable lifespan and adjustable stepping accuracy according to claim 2, characterized in that: When the preload rotating set screw (10) drives the actuator ring (7) to deflect in the radial direction, the actuator ring (7) drives the rotary transmission turntable (2) to rotate through friction each time. Due to the existence of the reaction force, the reaction force component along the tangential direction of the actuator ring (7) will drive the actuator ring (7) to rotate along its axis. Each rotation will change the contact surface of the friction pair, further improving the wear state of the contact surface, improving the repeatability and service life of the actuator, and making the accuracy of the inertial rotary actuator adjustable and the service life controllable.

4. The inertial rotary actuator with controllable lifespan and adjustable stepping accuracy according to claim 1, characterized in that: The rhombus ring (5-1) is an arc-shaped rhombus ring.

5. The inertial rotary actuator with controllable lifespan and adjustable stepping accuracy according to claim 1, characterized in that: The rotating load disk (3) is fixedly mounted on the rotating shaft of the rotating transmission turntable (2) by load disk mounting screws (4).

6. The actuation method of an inertial rotary actuator with controllable lifespan and adjustable stepping accuracy as described in any one of claims 1 to 5, characterized in that: The specific method for implementing the inertial rotary actuator is as follows: In order to make the rotary transmission turntable (2) drive the rotary load disc (3) to produce a clockwise displacement, the first step is to slowly apply voltage to the driving piezoelectric ceramic (5-2) from zero voltage to full stroke voltage, so that the driving piezoelectric ceramic (5-2) slowly extends along its axial direction, and similarly drives the actuating ring (7) to move slowly along the axial direction. At this time, the rotary transmission turntable (2) is provided with an upward static friction force by the actuating ring (7), which can overcome the downward inertial force. The rotary transmission turntable (2) is kept relatively stationary by the actuating ring (7), and an upward displacement is generated. Since the actuating ring (7) is installed on the rotary transmission turntable... (2) The eccentric position of the rotary transmission turntable (2) will cause the rotary transmission turntable (2) to rotate clockwise at this time; in the second step, the voltage of the driving piezoelectric ceramic (5-2) is rapidly reduced from the full stroke voltage to zero voltage, the driving piezoelectric ceramic (5-2) rapidly contracts along its axis, and drives the rotary transmission turntable (2) to retract rapidly, that is, rapidly generate counterclockwise rotation. However, due to the large inertia of the rotary transmission turntable (2), the downward displacement is less than the downward displacement of the actuating ring (7), that is, only a counterclockwise rotation less than the clockwise rotation in the first step will be generated. The difference between the rotation in the first step and the second step is a clockwise rotation angle. Repeat the first and second steps, and the rotary transmission turntable (2) will generate a sustained The continuous clockwise rotation causes the rotating load disk (3) to rotate continuously clockwise. To make the rotating transmission disk (2) rotate counterclockwise, the first step is to rapidly apply voltage to the driving piezoelectric ceramic (5-2) from zero voltage to full stroke voltage. The driving piezoelectric ceramic (5-2) rapidly extends along its axial direction, causing the rotating transmission disk (2) to rotate rapidly clockwise. At this time, the rotating transmission disk (2) is subjected to upward sliding friction force from the actuating ring (7). However, due to its large inertia, the upward displacement of the rotating transmission disk (2) is less than the upward displacement of the actuating ring (7), that is, a small clockwise rotation angle is generated. The second step is to apply voltage to the driving piezoelectric ceramic (5-2) from zero voltage to full stroke voltage. The driving voltage of 5-2) is slowly reduced to zero voltage, driving the piezoelectric ceramic (5-2) to slowly contract along the axial direction, which in turn drives the actuating ring (7) to slowly contract. At this time, the static friction force of the actuating ring (7) on the rotating transmission turntable (2) can overcome the inertial force. The rotating transmission turntable (2) and the actuating ring (7) remain relatively stationary, producing a downward displacement. That is, the amount of counterclockwise rotation produced is greater than the amount of clockwise rotation produced in the first step. The difference between the rotation in the first step and the second step is a counterclockwise rotation angle. Repeating the first and second steps, the rotating transmission turntable (2) produces a continuous counterclockwise rotation, thereby driving the rotating load disk (3) to produce a continuous counterclockwise rotation.

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