An anti-interference magnetic encoder

Abstract

The present invention provides an anti-interference magnetic encoder, which includes a magnetic sensor main body, a controller, and a data line for electrically connecting the two; the magnetic sensor main body includes a PCB board, a magnetic sensor chip, a first Type-C female socket, and a shielding shell covering the PCB board; the first Type-C female socket and the magnetic sensor chip follow the SPI communication protocol, and the data line includes a first Type-C male head unit connected to the first Type-C female socket, a second Type-C male head unit for connecting to a pre-configured second Type-C female socket of the controller and isolating and forwarding the transceiver data of the controller, and a data line main body connecting the two. The magnetic sensor main body also includes a filtering circuit. According to the present invention, it is possible to solve the problems of inconvenient replacement of the shielding wire and a large interface during the SPI high-speed data transmission of the existing magnetic encoder in order to shield electromagnetic interference as much as possible.

Description

Technical Field

[0001] The present invention belongs to the field of encoders, and more specifically, relates to an anti-interference magnetic encoder. Background Art

[0002] An encoder is a device that encodes signals (such as bitstreams) or data and converts them into signal forms that can be used for communication, transmission, and storage. In principle, encoders have the following categories: optical encoders, magnetic encoders, capacitive encoders, inductive encoders, etc. As an emerging technology, magnetic encoders are increasingly used in the market. The data interfaces for motor position sensing in the market are divided into: ABZ interface, PWM interface, I2C interface, SPI interface, etc. The position accuracy output by sensors under different interfaces is also different. Relatively speaking, the magnetic encoder with an SPI interface has the highest position output accuracy. For sensors of any interface, after the motor is powered on, they will be affected by electromagnetic interference, and among them, the sensors with SPI and I2C interfaces are the most sensitive to electromagnetic interference. In the prior art, a shielding system is basically adopted to solve the problem of electromagnetic interference suffered by magnetic encoders. One of the solutions is to use a customized shielded wire, but this method has the problem of inconvenient replacement of the shielded wire. Another solution is to use an M12 interface, but this solution has the problem of a large interface. Summary of the Invention

[0003] The object of the present invention is to solve the problems of inconvenient replacement of the shielded wire and a large interface in order to shield electromagnetic interference as much as possible during the SPI high-speed data transmission process of the existing magnetic encoder.

[0004] To achieve the above object, the present invention provides an anti-interference magnetic encoder.

[0005] According to the present invention, an anti-interference magnetic encoder is provided. The magnetic encoder includes a magnetic sensor main body and a data line for electrically connecting the magnetic sensor main body to a remote controller.

[0006] The magnetic sensor main body includes a PCB board, a magnetic sensor chip disposed on the PCB board, and a first Type-C female socket, and a shielding housing covering the PCB board.

[0007] The first Type-C female socket and the magnetic sensor chip follow the SPI communication protocol. The VBUS pin of the first Type-C female socket is connected to the VDD pin of the magnetic sensor chip, and the GND pin of the magnetic sensor chip and the GND pin of the Type-C female socket are connected to the same power ground.

[0008] The data cable includes a first Type-C male header unit, a second Type-C male header unit, and a data cable body connecting the two. The first Type-C male header unit is used to connect to the first Type-C female socket, and the second Type-C male header unit is used to connect to a pre-configured second Type-C female socket of the controller and isolate and forward the data transmitted and received by the controller.

[0009] The magnetic sensor body further includes an RC filter circuit, which is connected in series between the VBUS pin of the first Type-C female socket and the VDD pin of the magnetic sensor chip.

[0010] Optionally, the first Type-C male header unit includes a first PCB adapter board and a first Type-C male header provided on the first PCB adapter board. The first end of the data cable body is electrically connected to the first Type-C male header through the first PCB adapter board.

[0011] Optionally, the first Type-C male header is configured with a first shielding case.

[0012] Optionally, the second Type-C male header unit includes a second PCB adapter board and a second Type-C male header provided on the second PCB adapter board. The second end of the data cable body is electrically connected to the second Type-C male header through the second PCB adapter board;

[0013] The second Type-C male header unit further includes a digital isolation chip provided on the second PCB adapter board, and the digital isolation chip is used to isolate the SPI communication between the second Type-C male header and the data cable body.

[0014] Optionally, the second Type-C male header is configured with a second shielding case.

[0015] Optionally, the data cable body is a five-core shielded wire, namely a power line, a data transmission line, a data reception line, a chip select line, and a clock line.

[0016] The beneficial effects of the present invention are as follows:

[0017] An anti-interference magnetic encoder of the present invention, compared with the existing magnetic encoders, adopts a four-channel digital isolation chip and a shielding structure to improve the anti-interference ability. The magnetic sensor body is connected to the controller through the data cable of this solution to achieve high-speed SPI data transmission, greatly reducing the interference of the output signal of the magnetic encoder and solving the problems of inconvenient replacement of the shielded wire and the interface size in the current shielding solutions on the market.

[0018] As can be seen from the above content, the anti-interference magnetic encoder of the present invention can effectively solve the problems of inconvenient replacement of shielded wires and large interfaces in the existing magnetic encoder during SPI high-speed data transmission in order to shield electromagnetic interference as much as possible.

[0019] Other features and advantages of the present invention will be described in detail in the following specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention can be better understood by referring to the descriptions made in conjunction with the accompanying drawings in the following text, where the same or similar reference numerals are used in all the drawings to represent the same or similar components.

[0021] Figure 1 The principle block diagram of the anti-interference magnetic encoder according to an embodiment of the present invention is shown.

[0022] Figure 2 The electrical connection diagram between relevant power supply filter capacitors and resistors in the magnetic sensor chip according to an embodiment of the present invention is shown. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] In order to enable those skilled in the art to more fully understand the technical solution of the present invention, the exemplary embodiments of the present invention will be described more comprehensively and in detail below in conjunction with the accompanying drawings. Obviously, one or more of the embodiments of the present invention described below are only one or more of the specific ways to implement the technical solution of the present invention, and are not exhaustive. It should be understood that other ways belonging to a general inventive concept can be used to implement the technical solution of the present invention, and should not be limited by the exemplary embodiments described. Based on one or more embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0024] Embodiment: Figure 1 The principle block diagram of the anti-interference magnetic encoder according to an embodiment of the present invention is shown. Referring to Figure 1 , the anti-interference magnetic encoder according to an embodiment of the present invention, the magnetic encoder includes a magnetic sensor main body and a data line for electrically connecting the magnetic sensor main body to a remote controller;

[0025] The magnetic sensor main body includes a PCB board, a magnetic sensor chip and a first Type-C female socket provided on the PCB board, and a shielding housing covering the PCB board;

[0026] The communication protocol followed between the first Type-C female socket and the magnetic sensor chip is the SPI communication protocol. The VBUS pin of the first Type-C female socket is connected to the VDD pin of the magnetic sensor chip, and the GND pin of the magnetic sensor chip and the GND pin of the Type-C female socket are connected to the same power ground;

[0027] The data line includes a first Type-C male head unit, a second Type-C male head unit, and a data line body connecting the two. The first Type-C male head unit is used to connect to the first Type-C female socket, and the second Type-C male head unit is used to connect to a pre-configured second Type-C female socket of the controller and isolate and forward the data received and transmitted by the controller;

[0028] The magnetic sensor body further includes an RC filter circuit, and the RC filter circuit is connected in series between the VBUS pin of the first Type-C female socket and the VDD pin of the magnetic sensor chip.

[0029] Specifically, in the embodiments of the present invention, with reference to Figure 2 , the RC filter circuit includes a resistor and a capacitor; the first end of the resistor is connected to the VBUS pin of the first Type-C female socket, the common end of the second end of the resistor and the first end of the capacitor is connected to the VDD pin of the magnetic sensor chip, and the second end of the capacitor is connected to the power ground. The input ripple of the power supply is minimized as much as possible through the RC filter. Among them, the specific pin of the input end of the power supply connected to In can be changed, and the power input pin of the sensor chip connected to OUT. There are different numbers for the specific chip pins.

[0030] Further, in the embodiments of the present invention, the first Type-C male head unit includes a first PCB adapter board and a first Type-C male head provided on the first PCB adapter board. The first end of the data line body is electrically connected to the first Type-C male head through the first PCB adapter board. The first PCB adapter board is provided with six power data channels, namely a 5V power line, a 5V ground line, a data receiving line, a data sending line, a chip select line, and a clock line.

[0031] Still further, in the embodiments of the present invention, the first Type-C male head is configured with a first shielding case.

[0032] Still further, in the embodiments of the present invention, the second Type-C male head unit includes a second PCB adapter board and a second Type-C male head provided on the second PCB adapter board. The second end of the data line body is electrically connected to the second Type-C male head through the second PCB adapter board;

[0033] The second Type-C male unit further includes a digital isolation chip disposed on the second PCB adapter board. The digital isolation chip is used to isolate the SPI communication between the second Type-C male and the data line body. The second PCB adapter board is provided with eight power and data channels, namely, a 5V power line, a 3.3V power line, a 5V ground line, a 3.3V ground line, a data receiving line, a data sending line, a chip select line, and a clock line. The digital isolation chip includes four digital isolation channels, namely, the data receiving line, the data sending line, the chip select line, and the clock line.

[0034] Furthermore, in the embodiment of the present invention, the second Type-C male is configured with a second shielding case.

[0035] Furthermore, in the embodiment of the present invention, the data line body is a five-core shielded wire, namely, a power line, a data sending line, a data receiving line, a chip select line, and a clock line.

[0036] Specifically, in the embodiment of the present invention, a coaxial magnetic rotary position sensor chip AS5047P supporting the SPI interface is disposed on the PCB board of the magnetic sensor. A filter capacitor and a resistor are added to the power supply end. A first TYPE-C female socket serving as an external interface is also disposed on the PCB board and follows the SPI communication protocol with the sensor chip AS5047P. The coaxial magnetic rotary position sensor chip AS5047P cooperates with a radial magnet to implement motor position detection. The selection of the magnet is open, and it is ensured that it is a radial magnet. The fixed position of the magnet is on the rotor of the motor, and it is required that the magnetic field rotation center of the radial magnet is at the center of the surface-mounted end face of the sensor chip.

[0037] The data cable includes a first TYPE-C male head unit, a second TYPE-C male head unit, and a data cable body connecting the two. The data cable body is a 5-core shielded cable, which are the power supply line VCC, the data transmission line MOSI, the data reception line MISO, the chip select line CSN, and the clock line CLK respectively, to achieve SPI high-speed data communication. The shielding layer serves as the 6th line and is defined as the ground wire. The entire data cable includes a total external shielding structure. The first TYPE-C male head unit includes a first PCB adapter board and a first TYPE-C male head arranged on the first PCB adapter board. The first PCB adapter board is provided with 6 power and data channels, which are the 5V power supply line, the 5V ground wire, the data reception line, the data transmission line, the chip select line, and the clock line respectively. The first PCB adapter board is connected to the first TYPE-C female socket through the first TYPE-C male head to achieve SPI high-speed data communication. It is worth mentioning that the installation positions of the first TYPE-C male head and the first TYPE-C female socket can also be interchanged. The solution proposed in this embodiment is the optimal one. The purpose of setting the first TYPE-C male head on the first PCB adapter board is to reduce the volume of the first PCB adapter board. The second TYPE-C male head unit includes a second PCB adapter board and a second TYPE-C male head arranged on the second PCB adapter board. The second PCB adapter board is provided with 8 power and data channels, which are the 5V power supply line, the 3.3V power supply line, the 5V ground wire, the 3.3 ground wire, the data reception line, the data transmission line, the chip select line, and the clock line respectively. The second PCB adapter board is connected to the second TYPE-C female socket pre-set on the controller through the second TYPE-C male head to achieve SPI high-speed data communication. It is worth mentioning that the installation positions of the second TYPE-C male head and the second TYPE-C female socket can also be interchanged. The solution proposed in this embodiment is the optimal one. The purpose of setting the second TYPE-C male head on the second PCB adapter board is to reduce the volume of the second PCB adapter board.

[0038] A digital isolation chip ISO7241CDW is also provided on the second PCB adapter board. The digital isolation chip ISO7241CDW includes 4 digital isolation channels, which are the data transmission line MOSI, the data reception line MISO, the chip select line CSN, and the clock line CLK respectively. 5VDC and 5VGND are used for connecting the magnetic encoder end, and 3.3VDC and 3.3VGND are used for connecting the controller end. The digital isolation chip is used to isolate the SPI communication between the second Type-C male head and the data cable body. A four-channel digital isolation chip and a shielding structure are adopted to improve the anti-interference ability.

[0039] Although one or more embodiments of the present invention have been described above, those of ordinary skill in the art should understand that the present invention can be implemented in any other form without departing from its gist and scope. Therefore, the embodiments described above are illustrative rather than restrictive, and many modifications and substitutions will be obvious to those of ordinary skill in the art without departing from the spirit and scope of the present invention as defined by the appended claims.

Claims

1. An anti-interference magnetic encoder, characterized in that, The magnetic encoder includes a magnetic sensor body and a data line for electrically connecting the magnetic sensor body to a controller at a remote end; The magnetic sensor body includes a PCB board, a magnetic sensor chip disposed on the PCB board and a first Type-C female socket, and a shielding housing covering the PCB board; The first Type-C female socket and the magnetic sensor chip follow the SPI communication protocol. The VBUS pin of the first Type-C female socket is connected to the VDD pin of the magnetic sensor chip. The GND pin of the magnetic sensor chip and the GND pin of the Type-C female socket are connected to the same power ground; The data line includes a first Type-C male unit, a second Type-C male unit, and a data line body connecting the two. The first Type-C male unit is used to connect to the first Type-C female socket. The second Type-C male unit is used to connect to a pre-configured second Type-C female socket of the controller and isolate and forward the received and transmitted data of the controller; The magnetic sensor body further includes an RC filter circuit, and the RC filter circuit is connected in series between the VBUS pin of the first Type-C female socket and the VDD pin of the magnetic sensor chip; The first Type-C male unit includes a first PCB adapter board and a first Type-C male head disposed on the first PCB adapter board. The first end of the data line body is electrically connected to the first Type-C male head through the first PCB adapter board. The first PCB adapter board is provided with 6 power data channels, namely a 5V power line, a 5V ground line, a data receiving line, a data transmitting line, a chip select line, and a clock line; The second Type-C male unit includes a second PCB adapter board and a second Type-C male head disposed on the second PCB adapter board. The second end of the data line body is electrically connected to the second Type-C male head through the second PCB adapter board. The second PCB adapter board is provided with 8 power data channels, namely a 5V power line, a 3.3V power line, a 5V ground line, a 3.3V ground line, a data receiving line, a data transmitting line, a chip select line, and a clock line; The data line body is a five-core shielded wire, namely a power line, a data transmitting line, a data receiving line, a chip select line, and a clock line.

2. The anti-interference magnetic encoder according to claim 1, characterized in that, The first Type-C male head is configured with a first shielding case.

3. The anti-interference magnetic encoder according to claim 1, wherein The second Type-C male unit further includes a digital isolation chip disposed on the second PCB adapter board, and the digital isolation chip is used to isolate the SPI communication between the second Type-C male head and the data line body.

4. The anti-interference magnetic encoder according to claim 3, characterized in that The second Type-C male head is configured with a second shielding case.

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