A small integrated motor

Abstract

This invention relates to a small integrated motor, comprising a rear end cover, a PCB board, a rear cover, and a rotating shaft. The PCB board includes an upper plate for implementing drive functions, a lower plate for implementing encoder functions, and an inter-board connector for connecting the upper and lower plates. The rear end cover is provided with double-layer stepped fixing mechanisms for the upper and lower plates, respectively. Compared with the prior art, this invention has advantages such as minimizing motor size.

Description

Technical Field

[0001] This invention relates to an electric motor, and more particularly to a small integrated electric motor. Background Technology

[0002] With the rapid development of automation, computer, and electronic technologies, motor manufacturing technology has also advanced rapidly, which has placed higher demands on the invention, manufacturing, and control application technologies of small motors like the Nema8, and provided broader development space.

[0003] A servo control system is an operating system that automatically controls the mechanical motion of experimental equipment according to predetermined requirements. In many cases, a servo system specifically refers to a feedback system where the controlled variable (system output) is mechanical displacement or unit speed, and its main function is to ensure that the mechanical displacement distance (or mechanical rotation angle) accurately tracks the input displacement. To improve control accuracy and servo capability, position sensors, such as encoders, are usually added to the motor to provide the real-time position of the motor to the drive or control system. To achieve high integration, the motor and drive unit are often integrated together to meet the needs of many space-constrained applications, such as robot joints and medical devices. For small motors (such as Nema8 size and below), the limited space at the rear end cover makes the design and installation of the encoder and drive unit more difficult. The main technical drawbacks of small integrated motor products generally include:

[0004] 1) High integration requirements and large size are easy to achieve. It is difficult to design and arrange the components required for the drive unit and encoder without increasing the axial length and radial sluggishness of the motor.

[0005] 2) The product position feedback accuracy cannot be guaranteed. The position detection device on the PCB assembly cannot guarantee the concentricity requirement with the rotating shaft magnet, which can easily cause the magnet reading failure.

[0006] 3) Poorly designed connectors and other components can easily cause them to be under constant external tension, which poses a significant challenge to the lifespan of the connectors themselves.

[0007] A search of Chinese Patent Publication No. CN111313620A reveals a bus-type integrated motor based on fiber optic communication. This motor is an integrated unit comprising an interconnected motor body and a driver section. The driver section includes a separate driver board and a communication board. This integrated design of the motor and driver not only reduces the number of wires within the customer's overall system and lowers the risk of signal crosstalk, but also significantly saves structural space, facilitating miniaturization. However, this existing patent still has the following problems: the arrangement of the driver and encoder, as well as the connector installation method, cannot further enable motor miniaturization. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a small integrated motor.

[0009] The objective of this invention can be achieved through the following technical solutions:

[0010] According to one aspect of the present invention, a small integrated motor is provided, including a rear end cover, a PCB board, a rear cover and a rotating shaft. The PCB board includes an upper board for implementing a driving function, a lower board for implementing an encoder function and an inter-board connector for connecting the upper board and the lower board. The rear end cover is provided with a double-layer step fixing mechanism for the upper board and the lower board respectively.

[0011] As a preferred technical solution, the lower plate is closely attached to the rear end cover.

[0012] As a preferred technical solution, a magnetic induction chip is provided on the lower plate.

[0013] As a preferred technical solution, the double-layer step fixing mechanism includes an encoder fixing step, an encoder board mounting hole, a drive board fixing step, and a drive board mounting hole. The encoder fixing step and the encoder board mounting hole are respectively positioned and connected to the lower plate, and the drive board fixing step and the drive board mounting hole are respectively positioned and connected to the upper plate.

[0014] As a preferred technical solution, the encoder fixing step is provided with a step post for positioning, thereby ensuring the distance accuracy requirements between the magnetic induction chip and the magnet on the rotating shaft.

[0015] As a preferred technical solution, the inter-board connector is provided in three parts: a first inter-board connector, a second inter-board connector, and a third inter-board connector, which are used to achieve the minimum spacing between the two boards.

[0016] As a preferred technical solution, the first inter-board connector is a 3-pin inter-board connector, and the second and third inter-board connectors are 4-pin inter-board connectors.

[0017] As a preferred technical solution, baffles are provided on both sides of the slot position of the inter-board connector.

[0018] As a preferred technical solution, the lower plate adopts a segmented arc-shaped structure that cooperates with the rear end cover.

[0019] As a preferred technical solution, the upper board is equipped with an MCU chip, an RS485 transceiver, and an encoder signal connector.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] (1) The present invention implements the drive unit and encoder functions on two PCBs, an upper board and a lower board, which minimizes the radial dimension of the motor. The lower board is close to the rear end cover of the motor, so it has almost no effect on the axial length of the motor.

[0022] (2) The two PCB boards (upper board and lower board) of this invention are connected by an inter-board connector, which realizes the minimum spacing between the two boards and ensures that the axial length of the motor is minimized. At the same time, the double step of the rear end cover ensures the required distance accuracy and parallelism of the magnet and magnetic induction chip when the encoder (lower board) is installed, as well as the radial position of the upper board.

[0023] (3) The bottom PCB board (lower board) and the rear cover adopt an arc-shaped fit. Due to the processing reasons, it is difficult to make the PCB board into a precise circle, but it is necessary to use a circle to maintain concentricity with the magnet below. Therefore, a segmented arc is used to maintain the accuracy requirements. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the exploded structure of the present invention;

[0025] Figure 2 This is a schematic diagram of the structure of the lower plate of the present invention;

[0026] Figure 3 This is a schematic diagram of the structure of the upper plate of the present invention;

[0027] Figure 4 This is a schematic diagram of the structure of the rear end cover of the present invention;

[0028] Wherein, 1 is the rear end cover, 2 is the PCB board, 3 is the rear cover, 4 is the rotating shaft, 11 is the encoder mounting step, 12 is the encoder board mounting hole, 13 is the driver board mounting step, 14 is the driver board mounting hole, 21 is the upper board, 22 is the lower board, 23 is the inter-board connector, 211 is the MCU chip, 212 is the RS485 transceiver, 213 is the encoder signal connector, 221 is the magnetic induction chip, 231 is the first inter-board connector, 232 is the second inter-board connector, and 233 is the third inter-board connector. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0030] like Figure 1 As shown, a small integrated motor includes a rear end cover 1, a PCB board 2, a rear cover 3, and a rotating shaft 4. The PCB board 2 includes an upper plate 21 for implementing the driving function, a lower plate 22 for implementing the encoder function, and an inter-board connector 23 for connecting the upper plate 21 and the lower plate 22. The rear end cover 1 is provided with a double-layer step fixing mechanism for the upper plate 21 and the lower plate 22 respectively.

[0031] This invention addresses small-frame integrated motors (such as Nema8 and below) by dividing the PCB into an upper and lower board, which respectively implement the drive unit and encoder functions. The rear cover is redesigned with a double-step fixing method. The lower board's steps ensure the required distance accuracy between the magnetic induction chip and the magnet on the shaft, while the upper board's steps enable radial positioning of the upper board. Furthermore, the inter-board connector ensures precise distance between the two PCBs, minimizing the overall axial length of the motor. Screw holes and circular slots are added at the steps to ensure the concentricity and parallelism of the chip and magnet, and to prevent the PCB from detaching due to vibration during long-term use. Baffles are added on both sides of the connector slot to ensure even stress distribution on the PCB, increasing its lifespan.

[0032] like Figure 2 As shown, the lower plate 22 is closely attached to the rear end cover 1, and has almost no impact on the axial length of the motor. A magnetic induction chip 221 is provided on the lower plate 22. Three inter-board connectors 23 are provided: a first inter-board connector 231, a second inter-board connector 232, and a third inter-board connector 233, used to achieve the minimum spacing between the two boards. The first inter-board connector 231 is a 3-pin inter-board connector, and the second inter-board connector 232 and the third inter-board connector 233 are 4-pin inter-board connectors.

[0033] like Figure 4As shown, the double-layer step fixing mechanism includes an encoder fixing step 11, an encoder board mounting hole 12, a drive board fixing step 13, and a drive board mounting hole 14. The encoder fixing step 11 and the encoder board mounting hole 12 are respectively positioned and connected to the lower plate 22, and the drive board fixing step 13 and the drive board mounting hole 14 are respectively positioned and connected to the upper plate 21. The encoder fixing step 11 is provided with step posts for positioning, thereby ensuring the distance accuracy requirements between the magnetic induction chip 221 and the magnet on the rotating shaft 4.

[0034] The lower plate 22 adopts a segmented arc-shaped structure that cooperates with the rear cover 1. Due to the processing reasons, it is difficult to make the PCB board into a precise circle, but it is necessary to use a circle to maintain concentricity with the magnet below. Therefore, a segmented arc shape is used to maintain the accuracy requirements.

[0035] like Figure 3 As shown, the upper plate 21 is equipped with an MCU chip 211, an RS485 transceiver 212 and an encoder signal connector 213.

[0036] The specific installation process of this invention is as follows:

[0037] During installation, first align the lower PCB board (encoder function) with the rear cover slot, then tighten the outer screw holes. After tightening, solder the inter-board connector onto the lower PCB board, and then solder the upper board above the inter-board connector. This not only limits the isolation distance between the upper and lower PCB boards but also minimizes the distance between the two layers. Finally, use the double-stepped positioning posts to place the rear cover and secure it with screws.

[0038] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A small integrated motor, comprising a rear end cover (1), a PCB board (2), a rear cover (3), and a rotating shaft (4), characterized in that, The PCB board (2) includes an upper board (21) for implementing the driving function, a lower board (22) for implementing the encoder function, and an inter-board connector (23) for connecting the upper board (21) and the lower board (22). The rear end cover (1) is provided with a double-layer step fixing mechanism for the upper board (21) and the lower board (22) respectively. The double-layer step fixing mechanism includes an encoder fixing step (11), an encoder board mounting hole (12), a drive board fixing step (13) and a drive board mounting hole (14). The encoder fixing step (11) and the encoder board mounting hole (12) are respectively positioned and connected to the lower plate (22), and the drive board fixing step (13) and the drive board mounting hole (14) are respectively positioned and connected to the upper plate (21). The lower plate (22) adopts a segmented arc-shaped structure that cooperates with the rear cover (1), and a circular groove is added at the step.

2. The small integrated motor according to claim 1, characterized in that, The lower plate (22) is in close contact with the rear end cover (1).

3. A small integrated motor according to claim 1, characterized in that, The lower plate (22) is provided with a magnetic induction chip (221).

4. A small integrated motor according to claim 3, characterized in that, The encoder fixing step (11) is provided with a step post for positioning, thereby ensuring that the distance between the magnetic induction chip (221) and the magnet on the rotating shaft (4) meets the accuracy requirements.

5. A small integrated motor according to claim 1, characterized in that, The board connector (23) is provided in three parts, namely the first board connector (231), the second board connector (232) and the third board connector (233), which are used to achieve the minimum spacing between the two boards.

6. A small integrated motor according to claim 5, characterized in that, The first board connector (231) is a 3-pin board connector, and the second board connector (232) and the third board connector (233) are 4-pin board connectors.

7. A small integrated motor according to claim 1 or 5, characterized in that, The slot of the inter-board connector is provided with baffles on both sides.

8. A small integrated motor according to claim 1, characterized in that, The upper plate (21) is equipped with an MCU chip (211), an RS485 transceiver (212) and an encoder signal connector (213).

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