KR100584117B1 - The smallest type actuator - Google Patents

Abstract

The present invention relates to a micro actuator, the micro actuator (1) is composed of a shaft (2) and a magnet (3) inserted into the shaft (2), which is provided on the outside of the magnet (3) Bearing 6 provided on the left and right sides of the coil body 4 and the magnet 3 via the washer 5, the middle cover 7 on the outside thereof, and the front cover fixed to the front and rear of the middle cover 7. A motor 8 composed of an 8a and a rear cover 8b, a first stage carrier 11 in which the sun gear 9 and the planetary gear 10 are assembled, and a sun gear 9 in the first stage carrier 11; A two-stage carrier 12 connected through the planetary gear 10 and an output shaft 13a formed in front of the two-stage carrier 12 by connecting the sun gear 9 and the planetary gear 10 through the medium. A ring gear 14 which is composed of a three-stage carrier 13 and meshes with the planetary gear 10, and a front cover 16a and a rear cover 16b fixed to the front and rear portions of the ring gear 14 are fixed. And said A structure including a reducer 16 composed of a stop ring 15 provided in front of the front cover 16a, wherein the micro actuator can achieve high output, miniaturization, and long life of the actuator, By simplifying the actuator size and improving processability, the use of oilless bearings can increase the speed of the device.

Miniature Actuator, Motor, Reducer

Description

Miniature Actuator {THE SMALLEST TYPE ACTUATOR}

1 is an exploded perspective view showing the external appearance of a micro actuator according to the present invention,

Figure 2 is an exploded perspective view showing the motor structure of the micro actuator according to the present invention,

Figure 3 is a side cross-sectional view showing an assembled state of the motor according to the present invention,

4 is a perspective view showing a coil body of a motor according to the present invention;

5 is an exploded perspective view showing the structure of the reducer of the micro actuator according to the present invention;

Figure 6 is a side cross-sectional view showing an assembled state of the reducer according to the present invention,

7 is a perspective view showing the assembled state of the carrier, the sun gear and the planetary gear of the reduction gear according to the present invention.

Explanation of symbols on the main parts of the drawings

1: ultra-small actuator 2: shaft

2a: single 3: magnet

4 coil 4a connection

5: washer 6: bearing

7: middle cover 8: motor

8a: front cover 8b: rear cover

8b ': Drawout groove 9: Sun gear

10: planetary gear 11: single stage carrier

11a: plate 11b: pin

12: two-stage carrier 12a: plate

12b: Pin 13: 3-stage carrier

13a: output shaft 13b: plate

14: ring gear 15: stop ring

16: reducer 16a: front cover

16b: rear cover

The present invention relates to an actuator for driving a device. In particular, according to the simplification of a motor structure, the present invention is manufactured in a very small diameter of Φ3 mm or less, and in various high-tech products such as a small precision power or a high speed drive device due to the improvement of precision and machinability. The present invention relates to a micro actuator that can be used in various ways.

Currently, it is difficult to miniaturize the actuator so that the technology related to the small actuator required for micro robots or precision medical devices that require high precision and high power ratio cannot be possessed in Korea yet.

Therefore, the direction of technology development of the small actuator is a direction that satisfies the miniaturization, light weight and high performance simultaneously to meet the miniaturization of the application parts, and the limit to miniaturize the manufacturing technology of the small actuator using the current technology is about 3mm in outer diameter. It is believed that this is the limit, and new technology is required to be further miniaturized.

Therefore, in the case of foreign countries, to mention the current technology of manufacturing small actuators, we succeeded in developing products with outer diameters of Φ2.4mm and Φ6.0mm with planetary gear type gearheads. Produced by

In addition, the introduction of MEMS technology has remained the academic research of the outer diameter of Φ 3-5 mm, and has not been reported for commercialized products.

In addition, it has been reported that a combination of a small motor manufacturing technology and a gearhead manufacturing technology using MEMS technology has developed a motor having an outer diameter of Φ 1.9 mm and a micro motor combined with a gear head.

Meanwhile, in Korea, coreless winding technology is required when manufacturing a motor having an outer diameter of Φ5 mm or less. However, in Korea, coreless structure winding technology to be applied to an outer diameter of Φ10 mm or less has not yet been developed. In terms of size, as a vibration motor for mobile phones, motors with an outer diameter of Φ4mm have been developed in Korea and produced for domestic and export use. However, only motors exist without gear heads, and only the purpose of rotation is thousands of rpm.

However, the reason why it is difficult to develop or manufacture a small actuator as described above is that there is a problem in the manufacture of a bearing that can be used in a portion where a high speed rotation of 100,000 rpm occurs as the size of the actuator decreases. All ball bearings and air bearings used were limited in manufacturing, and there was a difficulty in miniaturization due to brushes and other components of the existing DC motor.

In addition, with the development of the small actuator, the optimum controller is developed together, but in the case of a very small size, current technology is very difficult to control precisely, and sensors such as a hall sensor attached for precision control are attached according to size constraints. In particular, it is more difficult to control as an electrical output signal at high speed, there is a problem of cost increase for general machining and maintenance of processing precision, and assembly of product due to difficulty in miniaturization of parts There were problems such as difficulty in maintaining quality.

Accordingly, the present invention has been devised in view of the above-described circumstances, and according to the simplification of the motor structure, the present invention has been manufactured in a very small diameter having a diameter of Φ3 mm or less, and also improved in precision and workability. The goal is to provide a micro actuator that can be used in many advanced products.

The present invention for achieving the object of the above bar, a rotor having a predetermined length and a rotating rotor and a cylindrical magnet inserted into the shaft, and the coil body is assembled to surround the outside of the magnet and the Cylindrical bearings installed on the left and right sides of the magnet through washers inserted and fixed to the shaft, and the intermediate cover and the front and rear portions of the intermediate cover configured to form the outer shape of the device with the parts wrapped, respectively. A motor consisting of a stator composed of a front cover and a rear cover to surround the motor; and a first stage carrier connected to the motor through a shaft and assembled with a sun gear and a planetary gear for actual driving, and a sun gear and a planetary gear on the first stage carrier. Connected to the second stage carrier and the two-stage carrier through the sun gear and planetary gear A drive unit consisting of a three-stage carrier having an output shaft in front thereof, a cylindrical ring gear that is engaged with the planetary gear while surrounding the outside of the drive unit, and a front cover fixed to support the front and rear parts of the ring gear; And a reducer formed of a rear cover and a stopper provided in front of the front cover and configured of a stop ring configured to support the output shaft of the three-stage carrier.

In addition, a stage having a different diameter may be formed on an outer circumference of the shaft of the motor to distinguish the magnet insertion portion and the bearing insertion portion, and to draw the connection of the coil body outside the rear cover of the motor. The drawing grooves are formed at equal intervals, and the coil body of the motor is formed by a self-bonding method, and the connection to be drawn is made in a delta connection method.

In addition, the first and second stage carriers of the reducer are manufactured by pressing a plurality of pins into the plate, and the third stage carrier is also manufactured by pressing the output shaft into the plate, and the sun gear, the planetary gear, and the ring gear of the reducer are wire-processed and Produced by electric discharge machining, the sun gear is assembled in the center of the front surface of the plate of the first and second stage carriers of the reducer, and the planetary gear is assembled in detail at a 120-degree angle on the back of the plate to keep the sun gear fixed. The planetary gear is to be smoothly rotated.

That is, the micro actuator formed of the above structure is composed of a combination of a brushless DC (BLDC) motor and a planetary gear reducer, and the BLDC motor is small and has a high output and is generated in the case of a conventional DC motor. It is possible to solve the problem of life and difficult to rotate at high speed, the planetary gear reducer is the same input and output shaft, has a large reduction ratio compared to the volume, it is possible to create a wide variety of reduction ratio and operating conditions.

Therefore, the micro actuator can improve the output, miniaturization and long life of the actuator by improving the existing DC motor to the BLDC motor, and improve the miniaturization and processability of the actuator size by simplifying the motor structure. The use of oilless bearings makes it possible to increase the speed of the device, and by improving the assembly precision, simplifying the assembly and miniaturization of various components that make up the small actuator, the micro actuator can be used in many high-tech products such as small precision power or high speed drive. You can use a variety.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is an exploded perspective view showing the external appearance of the micro actuator according to the invention, Figure 2 is an exploded perspective view showing the motor structure of the micro actuator according to the invention, Figure 3 is an assembled state of the motor according to the invention 4 is a perspective view showing a coil body of a motor according to the present invention, FIG. 5 is an exploded perspective view showing a speed reducer structure of the micro actuator according to the present invention, and FIG. Fig. 7 is a side sectional view showing the assembled state of the reducer according to the present invention. Fig. 7 is a perspective view showing the assembled state of the carrier, the sun gear and the planetary gear of the reducer according to the present invention.

The structure of the micro actuator 1 according to the present invention is a rotor consisting of a shaft (2) rotated with a predetermined length and a cylindrical magnet (3) inserted and fixed to the shaft (2), the magnet (3) Cylindrical bearing (6) which is installed via the washer (5) on the left and right sides of the magnet (3) in the state fixed to the coil body (4) and the shaft (2) assembled to surround the outside of the) and Intermediate cover 7 and the front cover 8a and rear cover 8b which are inserted into and fixed to front and rear of the intermediate cover 7 to form the outer shape of the device with the parts wrapped, respectively, to surround the bearing 6. A motor (8) consisting of a stator composed of a stator, a first stage carrier (11) connected to the motor (8) via a shaft (2) and assembled with a sun gear (9) and a planetary gear (10) for actual driving; A two-stage carrier 12 connected to the first-stage carrier 11 via a sun gear 9 and a planetary gear 10. A drive unit composed of a three-stage carrier 13 having an output shaft 13a formed in front thereof connected to the second stage carrier 12 via a sun gear 9 and a planetary gear 10; Cylindrical ring gear 14 engaged with the planetary gear 10 and the front cover 16a and the rear cover 16b and the front cover which are fixed to support the front and rear portions of the ring gear 14 while being provided. It includes a reducer 16 provided in front of the (16a) consisting of a fixing portion consisting of a stop ring (15) adapted to support the output shaft (13a) of the three-stage carrier (13).

Here, the characteristic of the micro actuator 1 is composed of a combination of the BLDC motor 8 and the planetary gear reducer 16, the specification of the motor 8 is 3mm in diameter The coreless BLDC motor type has a length of 10 mm and a no-load rotational speed of 50,000 rpm. The speed reducer 16 has a diameter of 3 mm, a length of 10 mm, a three-stage stagedlrh, a reduction ratio of 45: 1, and a planetary gear type. to be. The BLDC motor 8 has a small size and high output, and solves a problem of short life and high speed rotation that occur in a conventional DC motor. The planetary gear reducer 16 has the same input / output shaft. In addition, it has a large reduction ratio compared to the volume, and can create a wide variety of reduction ratios and operating conditions.

That is, as shown in FIGS. 2 and 3, the structure of the motor 8 constituting the micro actuator 1 is largely divided into a rotor and a stator. The rotor is part of the shaft 2 and the magnet 3, and the stator of the motor 8 is the front cover 8a and the rear cover 8b and the middle cover 7, the coil body 4, the bearing 6 And as a washer 5 part, this motor 8 is a coreless BLDC motor 8 without a core.

The bearing 6 of the motor 8 is installed in the state of being inserted inside the front cover 8a and the rear cover 8b to smoothly rotate the rotor of the motor 8, and the magnet 3 and A washer 5 is installed in the space between the bearings 6 to reduce friction generated when the rotor magnet 3 and the bearing 6 interfere with each other, and are assembled in front and rear of the intermediate cover 7. In order to facilitate the assembly of the cover (8a) and the rear cover (8b) and at the same time to prepare a concentricity, the front cover (8a) and the rear cover (8b) are respectively provided with steps.

Therefore, in the assembling structure of the motor 8, the magnet 3 is inserted into the center of the shaft 2, and the bearings 6 are respectively installed through the washers 5 in the front and rear of the magnet 3. The coil body 4 is installed on the outside of the magnet 3, and the middle cover 7 is fixed to the outside of the coil body 4, and the front cover (front and rear of each of the middle cover 7 is fixed). 8a) and the rear cover 8b are inserted and installed.

On the other hand, if the various parts constituting the motor 8 will be described in more detail by item, first, in the case of the shaft 2, the installation portion of the magnet (3) and the installation portion of the bearing (6) can be distinguished A stage 2a is provided on the outer circumferential surface to facilitate the coupling of the magnets 3, and the wiring 4a of the coil body 4 is drawn out from the outside of the motor 8 to the rear cover 8b of the motor 8. In order to facilitate the shape of the mold, three lead-out grooves 8b 'are formed at equal intervals, and the middle cover 7 is made of a cylindrical shape, and the magnet 3 is machined using an Nd sintered magnet. It is manufactured by processing, and the bearing 6 is manufactured into a mold using a containing sintered bearing.

And, as shown in Figure 4, the detailed structure of the coil body 4, the wire diameter is 0.04mm, the inner diameter is 2.1mm, the outer diameter is 2.6mm, the length of the coil body 4 to form a level of 6.5mm and The method of connecting the coil body 4 uses a delta connection method, and the method of forming the coil body 4 uses a self bonding method.

In addition, as shown in FIGS. 5 and 6, the structure of the speed reducer 16 constituting the ultra-small actuator 1 is fixed to a drive unit that is actually driven largely, thereby reducing the speed reducer 16. The driving part is divided into a fixed part for holding, and the driving part includes a planetary gear part (carrier, ring gear, sun gear) having three stages, and the fixed part surrounds the outer side of the reducer 16 and the planetary body of the reducer 16 Ring gear 14 engaged with gear 10, front cover 16a and rear cover 16b supporting front and rear of reducer 16, and stops to prevent shaking of final output end of reducer 16. It consists of a ring (15).

That is, in the assembly structure of the reducer 16, three planetary gears 10 are installed at the rear side, and a first stage carrier 11 in which the planetary gears 10 are assembled around the sun gear 9 is installed at the front thereof. The two-stage carrier 12 is installed on the front surface of the first-stage carrier 11 through the sun gear 9 and the planetary gear 10, and the sun gear 9 and the planetary gear 10 are installed as a medium. The three-stage carrier 13 is installed on the front of the second stage carrier 12, the output shaft 13a is installed on the front of the three-stage carrier 13, and the 1,2,3 stage carriers 11, Ring gears 14 meshing with planetary gears 10 are installed on the outer sides of the 12 and 13, and front and rear covers 16a and 16b are inserted into left and right ends of the ring gears 14, respectively. The stop ring 15 is installed at the front of the front cover 16a while being inserted into the output shaft 13a of the three-stage carrier 13.

Here, the front cover (16a) and the rear cover (16b) of the various components constituting the reducer 16 is designed in a simple shape and manufactured by general machining in order to increase the processing precision, the reducer (16) First and second stage carriers 11 and 12 are manufactured by pressing a plurality of pins 11b and 12b into disc-shaped plates 11a and 12a, and the three-stage carrier 13 also has an output shaft on the plate 13b. It is produced by press-fitting (13a), the sun gear 9, the planetary gear 10 and the ring gear 14 of the reducer 16 is produced by wire processing and electrical discharge machining.

As shown in FIG. 7, the carrier, sun gear 9 and the planetary gear 10 constituting the speed reducer 16 are assembled in the first and second stage carriers 11 and 12 of the speed reducer 16. The sun gear 9 is assembled at the center of the front surface of the plates 11a and 12a, and the planetary gear 10 is assembled at a 120 degree angle to the rear of the plates 11a and 12a. Thus, the sun gear 9 is fixed. In addition to maintaining the planetary gear 10 is to be smoothly rotated.

Therefore, the use of the micro-actuator (1) is a small precision power and high-speed drive actuator, wearable computer / micro PDA / IMT-2000 terminal / micro system (human body insertion endoscope and The micro actuator 1 is required for portable equipment such as a driving unit such as a micropump) / miniature advanced system (a micro system for gas / fluid analysis, a micro robot, a micro airplane, a micro camera, etc.).

As described above, according to the micro-actuator according to the present invention, the existing DC motor can be improved to the BLDC motor to achieve high output, miniaturization, and long life of the actuator, and the pole of the actuator size through the simplification of the motor structure. In addition to miniaturization and processability, the device can be speeded up by the use of oilless bearings.In addition, the assembly precision of various components that make up the micro actuator can be improved, the assembly simplification, and the miniaturization make it possible to use small precision power or high speed drive. It is possible to use a variety of ultra small actuators in many advanced products.

Claims (8)

A rotor composed of a shaft 2 to be rotated and a magnet 3 inserted into and fixed to the shaft 2, and a coil body 4 and the shaft 2 assembled to surround the outside of the magnet 3; A motor (8) consisting of a cylindrical bearing (6) inserted and fixed to each of the left and right sides of the magnet (3) and a stator configured to form an outer shape of the device with the parts wrapped; A drive unit comprising a planetary gear unit having three stages for actual driving while being connected to the motor 8 through a shaft 2, and a cylindrical ring gear 14 engaged with the planetary gear unit while surrounding the outer side of the drive unit. Miniature actuator comprising a; reducer (16) consisting of a fixed portion consisting of. The front cover (8a) and the rear cover (8b) according to claim 1, wherein the case portion is inserted into and fixed to the cylindrical intermediate cover (7) and front and rear of the intermediate cover (7) to surround the bearing (6). And a planetary gear unit having a sun gear 9 and a planetary gear 10 assembled therein, and a sun gear 9 and a planetary gear 10 connected to the first gear carrier 11. It consists of a two-stage carrier (12) to be connected, and a three-stage carrier (13) having an output shaft (13a) formed in front of the two-stage carrier (12) via a sun gear (9) and a planetary gear (10). Miniature actuator, characterized in that. 3. A shaft (2a) having a different diameter is formed on an outer circumferential surface of the shaft (2) of the motor (8) to distinguish between the magnet (3) insertion portion and the bearing (6) insertion portion. Ultra-small actuator characterized in that it is possible to give. 3. The pull-out grooves 8b 'according to claim 1 or 2 are provided so that the wires 4a of the coil body 4 can be pulled out of the rear cover 8b of the motor 8. Miniature actuator, characterized in that formed at intervals. The micro actuator according to claim 1 or 2, characterized in that the coil body (4) of the motor (8) is formed in a self-bonding manner and the connection (4a) drawn out is made in a delta connection system. The front cover (16a) and the rear cover (16b) is provided in front and rear of the ring gear (14) so as to support the front and rear portions of the ring gear (14) of the reducer (16). Miniature actuator, characterized in that the stop ring (15) is provided in front of the cover (16a) to support the output shaft (13a) of the three-stage carrier (13). The first and second stage carriers 11 and 12 are assembled by pressing a plurality of pins 11b and 12b into the plates 11a and 12a, and the three-stage carrier 13 also includes a plate 13b. An ultra-small actuator, characterized in that it is assembled by press-fitting the output shaft (13a). 3. The sun gear 9 is assembled to the center of the front surface of the plates 11a and 12a of the first and second stage carriers 11 and 12 of the reducer 16, and 120 degrees to the rear of the plates 11a and 12a. Miniature actuator, characterized in that the planetary gear (10) is assembled in detail at an angle to keep the sun gear (9) is fixed and the planetary gear (10) is smoothly rotated.

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