Simple brushless linear actuator

Abstract

A simple brushless linear actuator comprises a tail cover assembly, a rotor assembly and a stator assembly, the tail cover assembly comprises a cover plate, a circuit board mounting frame, a circuit board and circuit board contact pins, the cover plate and the circuit board mounting frame are of an integrated structure, and the circuit board contact pins are fisheye type circuit board contact pins and are connected with the circuit board. The stator assembly comprises a coil and a stator shell, the coil is connected with the circuit board through a connecting piece, the rotor assembly comprises a rotor shaft, a magnetic ring and an output shaft, and a magnet is arranged at the top end of the output shaft. And a Hall sensor is arranged on the circuit board and is adjacent to the magnet for induction. Machining procedures are simplified, machining and mounting are convenient, the space utilization rate is high, and working stability is good. The position change and the rotation direction are sensed mutually by the magnet and the Hall sensor on the circuit board, the matching reversing of an original commutator and a carbon brush is omitted, the precision of the rotation speed is accurately controlled, the working efficiency is improved, and the quality of the linear actuator is ensured.

Description

Technical Field

[0001] This invention relates to a power drive device, specifically to a linear actuator. Background Technology

[0002] Power drive devices can be divided into linear actuators, rotary actuators, etc. A linear actuator is an actuator that outputs linear motion, while a rotary actuator outputs rotary motion. A linear actuator (motor) consists of a rotor and a stator. The rotor is a rotating component used to convert electrical energy into mechanical energy and vice versa. Currently, linear actuators generally include a brush holder assembly (including the brush holder body, inductor, carbon brush, carbon brush spring, etc.), a tail cover assembly (including the cover plate, circuit board mounting frame, circuit board, circuit board pins, etc.), a stator assembly (including coils, stator housing), and a rotor assembly (including rotor shaft, magnetic coil, output shaft, 24-polarity magnet, commutator, bearings, etc.). They are called brushed linear actuators because of the cooperation between the commutator and carbon brushes (current is conducted to the rotor windings through the carbon brushes and commutator, generating a rotating magnetic field). However, they suffer from energy loss due to friction between the carbon brushes and commutator, requiring maintenance and replacement of worn carbon brushes, and have limited speed control accuracy. The tail cover assembly's cover plate and circuit board mounting frame are separate structures. The cover plate, circuit board mounting frame, and stator assembly require two processes: hot wire welding. The circuit board and circuit board pins require soldering. The stator pins and circuit board require conductive connection through plastic-coated inserts on the cover plate. Their manufacturing process is cumbersome, their structure complex, their operation unstable, and their efficiency low. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a simple brushless linear actuator that is easy to process and install, and has stable operation.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a simplified brushless linear actuator, comprising a tail cover assembly, a rotor assembly, and a stator assembly. The tail cover assembly includes a cover plate, a circuit board mounting frame, a circuit board, and circuit board pins. The cover plate and the circuit board mounting frame are an integral structure. The circuit board pins are fisheye-shaped circuit board pins connected to the circuit board. The stator assembly includes a coil and a stator housing. The coil is connected to the circuit board via a connecting piece. The rotor assembly includes a rotor shaft, a magnetic coil, and an output shaft. A magnet is mounted on the top of the output shaft.

[0005] The circuit board has a Hall sensor that senses the magnet in conjunction with it. The Hall sensor is a 3D Hall sensor, capable of sensing the magnet's direction and 3D position. The magnet is a bipolar magnet, generating approximately 4096 pulses per revolution, resulting in very stable position control.

[0006] With this invention, the cover plate and circuit board mounting frame are integrated into a single structure, and the circuit board pins are fisheye-shaped, simplifying the processing steps, facilitating installation, increasing space utilization, and ensuring good operational stability. The position change and rotation direction are sensed by the interaction between the magnet and the Hall sensor on the circuit board, eliminating the need for the original commutator and carbon brushes for switching, thus accurately controlling the rotational speed, improving working efficiency, and ensuring the quality of the linear actuator. Attached Figure Description

[0007] Figure 1 This is a schematic diagram of the structure of the simplified brushless linear actuator of the present invention. Detailed Implementation

[0008] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0009] Reference Figure 1 The present invention relates to a simplified brushless linear actuator, comprising a tail cover assembly 1, a rotor assembly 4, and a stator assembly 2. The tail cover assembly 1 includes a cover plate 11, a circuit board mounting frame 14, a circuit board 12, and circuit board pins 13. The cover plate 11 and the circuit board mounting frame 14 are integrally formed. The circuit board pins 13 are fisheye-shaped and connected to the circuit board 12. The stator assembly 2 includes a coil 23 and a stator housing 22. The coil 23 is connected to the circuit board 12 via a connecting piece 21. The rotor assembly 4 includes a rotor shaft 42 (and a bearing 43), a magnetic coil 44, and an output shaft 45. A magnet 41 is mounted on the top of the output shaft 45. A guide sleeve assembly 3 is mounted on the output shaft 45 and below the rotor shaft 42. The circuit board 12 is installed into the circuit board mounting frame 14 from bottom to top. The magnet 41 is mounted on the top of the output shaft 45 by hot riveting, resulting in good assembly stability and eliminating the need for other mounting accessories. The lower end of the output shaft 45 is the power output end.

[0010] The circuit board 12 is equipped with a Hall sensor 15, which is adjacent to and senses the magnet 41. The Hall sensor 15 is a 3D Hall sensor, capable of sensing the direction and 3D position of the magnet. The magnet 41 is a bipolar magnet. In this invention, the magnetic coil 44 of the rotor assembly 4 and the coil 23 of the stator assembly mutually induce each other, driving the rotor shaft 42 and the output shaft 45 to rotate and mesh, causing the output shaft to perform linear extension and retraction. The magnet 41 also moves up and down with the linear extension and retraction of the output shaft 45. The 3D Hall sensor on the circuit board senses the 3D position and rotation direction of the bipolar magnet to precisely control the rotational speed and ensure smooth power output from the output shaft.

Claims

1. A simplified brushless linear actuator, comprising a tail cover assembly, a rotor assembly, and a stator assembly, wherein the tail cover assembly includes a cover plate, a circuit board mounting frame, a circuit board, and circuit board pins, characterized in that: The cover plate and the circuit board mounting frame are an integral structure. The circuit board pins are fisheye-shaped circuit board pins connected to the circuit board. The stator assembly includes a coil and a stator housing. The coil is connected to the circuit board through a connecting piece. The rotor assembly includes a rotor shaft, a magnetic coil, and an output shaft. A magnet is mounted on the top of the output shaft.

2. The simplified brushless linear actuator as described in claim 1, characterized in that: The circuit board has a Hall sensor that senses the magnet in its proximity.

3. The simplified brushless linear actuator as described in claim 2, characterized in that: The Hall sensor is a 3D Hall sensor.

4. The simplified brushless linear actuator as described in claim 2 or 3, characterized in that: The magnet is a bipolar magnet.

5. The simplified brushless linear actuator as described in claim 1, characterized in that: The magnet is mounted on the top of the output shaft by heat riveting.

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