KR20240096059A - A Smart Actuator Integrated with a Reducer and an Encoder - Google Patents

Abstract

The present invention relates to a smart actuator integrated with a reducer and encoder. The smart actuator with integrated reducer and encoder includes a controller (11); BLDC motor (12) operated by the controller (11); Encoder (13) that detects the number of rotations and speed of the BLDC motor (12); A reducer 14 having a planetary gear structure including a sun gear 143 rotated by the motor shaft 123 of the BLDC motor 12 and a satellite gear 146 rotated by the sun gear 143; and an output shaft (15) operated by a reducer (14).

Description

A Smart Actuator Integrated with a Reducer and an Encoder}

The present invention relates to a smart actuator integrated with a reducer and encoder, and more specifically, to a smart actuator integrated with a reducer and encoder in which a reducer and an encoder are integrated into a motor.

An actuator corresponds to a driving device that generates power for the operation of machines such as intelligent convergence processing machines, intelligent 3D rapid prototyping machines, or intelligent robots. These actuators can be divided into those that use electricity and those that use pressure such as hydraulic or pneumatic. The pressure-using method has the advantage of being able to generate a large force, but has the disadvantage of requiring an additional device, slow response during the control process, and showing non-linearity. For this reason, electric drive methods are applied to the operation of precision machines, and electric motors correspond to this. In order for a motor to be used as an actuator, a reducer, sensor, or control means must be combined with it. In relation to such actuators, Patent Publication No. 10-2018-0061460 discloses a robot joint actuator. Additionally, Patent Publication No. 10-2022-0052696 discloses a smart actuator for robots. In order to drive a robot or similar precision machine, the actuator needs to be structurally simple and have a means to appropriately detect the occurrence of a driving error. However, the prior art does not disclose an actuator with such a structure.

The present invention is intended to solve the problems of the prior art and has the following purposes.

Prior art 1: Patent publication number 10-2018-0061460 (Chung-Ang University Industry-Academic Cooperation Foundation, published on December 19, 2018) Robotic joint actuator Prior Art 2: Patent Publication No. 10-2022-0052696 (Neuromeka Co., Ltd., published on April 28, 2022) Smart actuator for robots modularized based on torque value

The purpose of the present invention is to provide a smart actuator integrated with a reducer and an encoder that can detect the gear position of the reducer while the reducer and encoder are integrated with the motor.

According to a preferred embodiment of the present invention, a smart actuator integrated with a reducer and an encoder includes a controller; BLDC motor operated by a controller; Encoder that detects the number of rotations and speed of the BLDC motor; A reducer with a planetary gear structure including a sun gear rotated by the motor shaft of the BLDC motor and a satellite gear rotated by the sun gear; and an output shaft operated by a reducer.

According to another suitable embodiment of the present invention, the BLDC motor includes a rotor formed in a ring shape and consisting of a plurality of unit magnetic poles formed along the circumference of the ring; and a pair of linear plate insulators disposed facing each other and a plurality of unit coils disposed between the pair of linear plate insulators.

According to another preferred embodiment of the present invention, the reducer includes three satellite gears consisting of a pair of circular substrates arranged to face each other and a plurality of meshing cylinders whose ends are fixed to the pair of circular substrates.

The smart actuator integrated with a reducer and encoder according to the present invention can be applied to the operation of an intelligent convergence processing machine, an intelligent 3D rapid prototyping machine, or an intelligent robot. The actuator according to the present invention is driven by a BLDC motor and simplifies the motor structure by using a rotor with a multipole magnetization structure and a stator with a modular structure. In addition, the actuator according to the present invention uses a reducer using planetary gears with small backlash, enabling precise control. The actuator according to the present invention can be applied to various industrial automation machines, and the present invention is not limited thereby.

Figure 1 shows an embodiment of a smart actuator integrated with a reducer and encoder according to the present invention.
Figure 2 shows an embodiment of a motor for an actuator according to the present invention.
Figure 3 shows an embodiment of a reducer for an actuator according to the present invention.
Figure 4 shows an embodiment of the gear rotation detection structure according to the present invention.
Figure 5 shows an embodiment of the operating structure of the actuator according to the present invention.

Below, the present invention will be described in detail with reference to the embodiments shown in the attached drawings, but the examples are for a clear understanding of the present invention and the present invention is not limited thereto. In the description below, components having the same reference numerals in different drawings have similar functions, so unless necessary for understanding the invention, the description will not be repeated, and well-known components will be briefly described or omitted, but the present invention It should not be understood as being excluded from the embodiments.

Figure 1 shows an embodiment of a smart actuator integrated with a reducer and encoder according to the present invention.

Referring to Figure 1, the smart actuator integrated with a reducer and encoder includes a controller (11); BLDC motor (12) operated by the controller (11); Encoder (13) that detects the number of rotations and speed of the BLDC motor (12); A reducer 14 having a planetary gear structure including a sun gear 145 rotated by the motor shaft 123 of the BLDC motor 12 and a satellite gear 146 rotated by the sun gear 143; and an output shaft (15) operated by a reducer (14).

The entire operation of the actuator can be controlled by the controller 11, which may include control means for controlling the operation and communication means such as EtherCAT, CAN, RS-485, Wi-Fi or LTE/3G. You can. The BLDC motor 12 can be driven by the controller 11, and the BLDC motor 12 includes a rotor 122 made of a permanent magnet and rotating; A stator 121 disposed on the circumferential surface of the rotor 122; A sensor shaft 124 extending in one direction from the rotor 122; and a motor shaft 123 connected to the rotor 122. The encoder 13 or resolver may be integrally combined with the BLDC motor 12, and includes a rotation unit 131 fixed to and rotating on the sensor shaft 124; A fixing unit 132 disposed on a fixing board coupled to the stator 121 of the BLDC motor 12 and detecting the position of the rotation unit 131; And it may include signal processing means for processing the position detection signals of the rotation unit 131 and the fixed unit 132. The signal processing means can communicate wirelessly with the controller 11, and the position of the detected BLDC motor 12 can be transmitted to the controller 12. A reducer 14 may be connected to the motor shaft 123, and the reducer 14 may have a planetary gear structure. Specifically, the input shaft 144 of the reducer 14 may be connected to the motor shaft 123, and the sun gear 143 may be rotated by the input shaft 144. A first satellite gear 146 is disposed on the circumferential surface of the sun gear 143 and can be rotated by engaging with the sun gear 143, and the connection gear 141 is engaged by the first satellite gear 146 and can be rotated. . Additionally, the first satellite gear 145 may be engaged and rotated inside the connecting gear 141, and the ring gear 142 may be engaged and rotated outside the connecting gear 141. And the output shaft 15 can be connected to the ring gear 142, and a machine such as an intelligent convergence processing machine, an intelligent 3D rapid prototyping machine, or an intelligent robot can be operated by the output shaft 15.

The rotation or rotational speed of at least one gear forming the reducer 14 may be detected, for example the rotation of the ring gear 142 may be detected by the gear detection module 16 . The rotation speed or rotation angle of the gear detected by the gear detection module 16 may be transmitted to the controller 11, and the controller 11 may determine the rotation speed or rotation angle of the motor 12 and the ring gear 142. The error can be calculated by comparing the rotation speed or rotation angle, and the operation of the motor 12 can be appropriately adjusted accordingly. The operation of the BLDC motor 12 by the controller 11 may be performed in various ways, and the present invention is not limited thereby.

Figure 2 shows an embodiment of a motor for an actuator according to the present invention.

Referring to FIG. 2, the BLDC motor 12 includes a rotor 21 that has a ring shape and consists of a plurality of unit magnetic poles 21_1 to 21_L formed along the circumference of the ring; and a pair of linear plate insulators 23 disposed facing each other and a plurality of unit coils 25_1 to 25_K disposed between the pair of linear plate insulators 23. The BLDC motor may be comprised of a rotor 21 and a stator disposed on a circumferential surface of the rotor 21, and the rotor 21 may have a ring shape. Specifically, unit magnetic poles 21_1 to 21_L of the S and N poles may be formed continuously on the rotor base extending in a linear strip shape. In this way, when the rotor base is magnetized with unit magnetic poles 21_1 to 21_L with the S and N poles alternating, both ends of the rotor base can be connected to create a ring-shaped rotor 21. Referring to (b) of FIG. 2, the stator may be made of a serial multi-core structure. To form a stator of a multi-core structure, an insulating fixing plate 22 in the shape of a circular band can be prepared, and a plurality of fixing holes 22_1 to 22_N are formed at regular intervals along the circumferential direction of the circular band with a certain width. It can be. Each fixing hole 21_1 to 22_N may extend along the radial direction. The series-shaped multi-core consists of a pair of linear plate insulators (23); a plurality of unit coils (25_1 to 25_K) disposed between a pair of linear plate insulators (23); and plate-shaped fixing pins (24_1 to 24_K) coupled to both ends of each unit coil (25_1 to 25_K). The linear plate insulator 23 may be made of a flexible synthetic resin material, and the ends of the fixing pins 24_1 to 24_K may be inserted into the fixing holes 22_1 to 22_N. The multi-core may be made into a circular ring shape, and in this state, the insulating fixing plate 22 may be coupled to the lower and upper sides of the ring-shaped multi-core. Specifically, the insulating fixing plate 22 may be fixed to the multi-core as the fixing pins 24_1 to 24_K are inserted into the fixing holes 22_1 to 22_N. The rotor 21 or stator can be made in various ways and the present invention is not limited thereby.

Figure 3 shows an embodiment of a reducer for an actuator according to the present invention.

Referring to FIG. 3, the reducer 14 includes a pair of circular substrates 341a and 341b arranged to face each other and a plurality of engaging cylinders 343_1 whose both ends are fixed to the pair of circular substrates 341a and 341b. to 343_K)) and includes three satellite gears 34a, 34b, and 34c. The reducer 14 includes a casing 31 that has an overall hollow cylindrical shape and a receiving space; A sun gear (32) located at the center of the casing (31); three satellite gears (34a, 34b, 34c) disposed on the circumferential surface of the sun gear (32); and a ring gear 33 engaged with three satellite gears 34a, 34b, and 34c. A sun gear 32 disposed on a separation plate 35 inside the casing 31 and having a connection shaft connected to the motor shaft may be disposed at the center of the casing 31 and around the circumference of the sun gear 32. Three satellite gears 34a, 34b, and 34c may be arranged on the surface. And the ring gear 33 is arranged to surround the three satellite gears 34a, 34b, and 34c, and the casing 31 is sealed by the cover 36 to form the reducer 14. Referring to the right side of FIG. 3, the satellite gear 34a is a pair of circular substrates 341a and 341b arranged to face each other and a plurality of engagements at both ends of which are fixed to the pair of circular substrates 341a and 341b. It may be composed of cylinders (343_1 to 343_K). Specifically, a plurality of engaging cylinders 343_1 to 343_K may be arranged in a circle, and fixing tabs 346 may be formed at both ends of each engaging cylinder 343_1 to 343_K. A pair of fixing plates 342a and 342b having fixing holes 344a and 344b in which fixing tabs 346 are inserted and fixed on both sides of the engaging cylinders 343_1 to 343_K are coupled, and a pair of fixing plates 342a , A pair of circular substrates 341a and 341b may be coupled to the outside of 342b). The satellite gears 34a, 34b, and 34c are made with this structure, so that the reducer 14 is made small overall and can transmit a large torque. Additionally, backlash is reduced to enable precise control.

Figure 4 shows an embodiment of the gear rotation detection structure according to the present invention.

Referring to FIG. 4, a detection area 41 is formed at one point on the circumference of the circular ring gear 33, and a detection sensor 42 may be placed outside the ring gear 33. The detection area 41 may be formed, for example, by inserting a permanent magnet, applying a magnetic coating, or partially magnetizing it. The detection sensor 42 may be a variety of sensors capable of detecting that the detection area 41 is approaching or moving away, and may be, for example, a Hall sensor. The detection area 41 moving away or getting closer can be detected by the detection sensor 42 and transmitted to the position calculation unit 43, and the position calculation unit 43 calculates the angular velocity and rotation speed of the ring gear 33. can be calculated and transmitted to the controller 11. Based on the transmitted information, the controller 11 can calculate the operating error by comparing the angular velocity of the motor and the angular velocity of the ring gear 33. The above detection area 41 may be formed on the ring gear 33 or the satellite gears 34a, 34b, and 34c. The positions of various gears 33, 34a, 34b, 34c can be detected and the present invention is not limited thereby.

Figure 5 shows an embodiment of the operating structure of the actuator according to the present invention.

Referring to FIG. 5, the motor may be operated by the motor operation unit 51, and the rotational speed or angular velocity of the motor may be detected by the motor angle detection unit 52, such as an encoder or resolver. The rotation angle or number of rotations of the gear forming the reducer can be detected by the gear rotation detection unit 53, and the operating state of the output shaft, such as the number of rotations or torque of the output shaft, can be detected by the output shaft detection unit 54. . Information detected by the motor angle detection unit 52, gear rotation detection unit 53, and output shaft detection unit 54 may be transmitted to the error calculation unit 55. The error calculation unit 54 can calculate the operating error that occurs during the operation of the motor, reducer, and output shaft, and the calculated error can be transmitted to the compensation data generation module 56 to generate compensation data. The compensation data may include data that compensates for errors in the operation of a predetermined motor in order to generate the output required from the output shaft, and such compensation data may be transmitted to the controller 11. The controller 11 may operate the motor operation unit 51 based on the compensation data. Operation control of the motor by the controller 11 may be accomplished in various ways, and the present invention is not limited thereby.

Although the present invention has been described in detail above with reference to the presented embodiments, those skilled in the art will be able to make various variations and modifications without departing from the technical spirit of the present invention by referring to the presented embodiments. . The present invention is not limited by such variations and modifications, but is limited by the claims appended below.

11: Controller 12: BLDC motor
13: encoder 14: reducer
15: output shaft 21: rotor
23: Insulator 25_1 to 25_K: Unit coil
34a, 34b, 34c: satellite gear 123: motor shaft
143: sun gear 146: satellite gear
341a, 341b: circular substrate 343_1 to 343_K: engaging cylinder

Claims (3)

Controller (11);
BLDC motor (12) operated by the controller (11);
Encoder (13) that detects the number of rotations and speed of the BLDC motor (12);
A reducer 14 having a planetary gear structure including a sun gear 143 rotated by the motor shaft 123 of the BLDC motor 12 and a satellite gear 146 rotated by the sun gear 143; and
A smart actuator integrated with a reducer and encoder including an output shaft (15) operated by a reducer (14). The method according to claim 1, wherein the BLDC motor (12) is a ring-shaped rotor (21) made of a plurality of unit magnetic poles (21_1 to 21_L) formed along the circumference of the ring; and a pair of linear plate insulators 23 disposed facing each other and a plurality of unit coils 25_1 to 25_K disposed between the pair of linear plate insulators 23. A smart integrated reducer and encoder. Actuator. The method of claim 1, wherein the reducer 14 includes a pair of circular substrates 341a and 341b arranged to face each other and a plurality of engaging cylinders 343_1 to 343_1, both ends of which are fixed to the pair of circular substrates 341a and 341b. 343_K)) Smart actuator integrated with a reducer and encoder including three satellite gears (34a, 34b, 34c).