A needle plate position detection circuit and device suitable for electric reset on a flat knitting machine
By installing a Hall sensor and a needle plate position detection circuit with a processing unit on the flat knitting machine, the problem of uncertain needle plate position after power failure is solved, achieving accurate position feedback and efficient operation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHEJIANG HENGQIANG TECH CO LTD
- Filing Date
- 2026-03-09
- Publication Date
- 2026-06-12
AI Technical Summary
When the flat knitting machine loses power, it cannot accurately determine the position of the needle plate, leading to knitting errors and affecting operating efficiency.
The needle plate position detection circuit consists of two Hall sensors, a Hall detection unit, and a processing unit. The Hall sensors detect the motor rotation, the processing unit calculates the number of motor rotations, and the power supply unit provides energy when power is lost, ensuring accurate feedback of the needle plate position when power is restored.
This avoids repeated zeroing and correction, improves the operating efficiency of the flat knitting machine, ensures counting accuracy and stability, and prevents damage to components.
Smart Images
Figure CN122192136A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of needle plate position detection technology for power-on reset of flat knitting machines, and in particular to a needle plate position detection circuit and device suitable for power-on reset of flat knitting machines. Background Technology
[0002] Currently, the raising and lowering mechanism of a flat knitting machine uses a motor and gears to drive a belt, which in turn moves the needle plate up and down. Regardless of the motor used, the real-time position of the motor needs to be known. The motor encoder detection circuit provides feedback on the current needle position, and then the motor drive circuit controls the motor to reach the desired position. The encoder circuit provides real-time, high-speed position feedback, forming a position closed loop. However, when the system is turned off, the motor encoder circuit cannot provide feedback on the motor position. If the needle plate moves during this period, and more than one revolution, the system will not be able to know the true position of the needle plate after power is restored. This will cause knitting errors, requiring a zeroing operation to correct them, thus affecting operating efficiency. Summary of the Invention
[0003] To address the problems existing in the prior art, this specification describes a needle plate position detection circuit and device suitable for power-on reset of a flat knitting machine through one or more embodiments.
[0004] According to a first aspect, a needle plate position detection circuit suitable for power-on reset of a flat knitting machine is provided. The circuit includes two Hall sensors disposed around the needle plate drive motor, two Hall detection units electrically connected to the two Hall sensors, a processing unit electrically connected to the Hall detection units, and a power supply unit electrically connected to the processing unit. The two Hall sensors generate rotation signals when the needle plate drive motor rotates. After receiving the rotation signals, the two Hall detection units send the rotation signals to the processing unit. The processing unit calculates the number of rotations of the needle plate drive motor when the flat knitting machine is powered off based on the rotation signals. The power supply unit is used to provide energy to the needle plate position detection circuit when the flat knitting machine is powered off.
[0005] Preferably, the angle formed by the connection of the two Hall sensors and the needle plate drive motor is a right angle.
[0006] Preferably, the Hall detection unit includes a first capacitor, a first end of which is electrically connected to a first interface of the Hall sensor, and a second end of which is electrically connected to a second interface of the Hall sensor and the power supply unit.
[0007] Preferably, the Hall detection unit further includes a second capacitor and a first resistor, the first end of the first resistor is electrically connected to the third interface of the Hall sensor, the second end of the first resistor is electrically connected to the first end of the second capacitor and the processing unit, and the second end of the second capacitor is grounded.
[0008] Preferably, the power supply unit includes a battery, with a first end of the battery electrically connected to the Hall detection unit and the processing unit, and a second end of the battery grounded.
[0009] Preferably, the power supply unit further includes a reverse protection diode, the first end of which is electrically connected to the Hall detection unit and the processing unit, and the second end of which is electrically connected to the battery.
[0010] Preferably, the processing unit includes an MCU, the first and second interfaces of the MCU are respectively connected to the two Hall effect detection units, the eighth interface of the MCU is electrically connected to the first terminal of the first diode, the ninth interface of the MCU is electrically connected to the first terminal of the sixth resistor, and the second terminal of the first diode and the second terminal of the sixth resistor are electrically connected to the motor encoder detection circuit.
[0011] Preferably, the operating current of the needle plate position detection circuit is less than or equal to 2uA.
[0012] According to a second aspect, a needle plate position detection device suitable for power-on reset of a flat knitting machine is provided, characterized in that the device encapsulates a needle plate position detection circuit as described in the first aspect.
[0013] According to a third aspect, a flat knitting machine is provided, characterized in that the flat knitting machine includes a needle plate position detection device as described in the second aspect.
[0014] The beneficial effects of this invention are as follows:
[0015] 1. The circuit and device provided in the embodiments of this specification enable the entire needle plate position detection circuit to operate when the flat knitting machine is powered off by setting a power supply unit, and set a Hall sensor to detect the rotation of the needle plate drive motor. After receiving the rotation signal, the Hall detection unit sends the rotation signal to the processing unit. The processing unit calculates the number of rotations of the needle plate drive motor when the flat knitting machine is powered off based on the rotation signal. When the flat knitting machine is powered on again, the number of rotations of the needle plate drive motor calculated by the processing unit is fed back to the motor coding detection circuit. The motor coding detection circuit controls the motor to reach the specified position as needed by the motor drive circuit, thereby avoiding repeated zeroing correction and improving the operating efficiency of the flat knitting machine.
[0016] 2. In the circuit and device provided in the embodiments of this specification, the angle formed by the two Hall sensors connected to the needle plate drive motor is a right angle. When the two Hall sensors are arranged with a 90° phase difference, the two output pulse signals have a phase difference: during forward rotation, phase A leads phase B by 90°; during reverse rotation, phase B leads phase A by 90°. If a single Hall sensor outputs N pulses per revolution, the two orthogonal Hall sensors can achieve a fourfold frequency multiplication (by detecting the combination of rising and falling edges). Each complete cycle detected (e.g., 4 edge changes) can be counted as 1 / N revolutions. Combined with direction information, the number of revolutions can be accumulated bidirectionally, avoiding counting errors caused by reverse rotation.
[0017] 3. The circuits and devices provided in the embodiments of this specification are susceptible to interference from switching noise, power supply ripple, and radio frequency interference in the strong electromagnetic environment of a motor. These interferences are usually manifested as glitches, spikes, or high-frequency oscillations, which may be misjudged as valid edges, leading to counting errors or misjudgments of direction. The second capacitor and the first resistor can attenuate high-frequency components and retain useful low-frequency signals (such as the square wave edge of the Hall switch), thereby improving the signal-to-noise ratio. The second capacitor and the first resistor smooth the rising / falling edges of the signal, avoiding multiple triggers in a short period of time, ensuring that each magnetic pole change produces only one clean transition, thereby eliminating signal jitter.
[0018] 4. The circuit and device provided in the embodiments of this specification have a reverse protection diode that only allows current to flow in the correct direction and cuts off when the current flows in the opposite direction. When the positive and negative terminals are reversed due to human error, wiring error or confusion of plug polarity, the reverse protection diode will cut off, thereby preventing the components of the pin plate position detection circuit from being damaged or burned out. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0020] Figure 1 This is a schematic diagram of the structure of a needle plate position detection circuit applicable to the power-on reset of a flat knitting machine in a specific implementation of this manual;
[0021] Figure 2 This is a schematic diagram of the Hall sensor arrangement in a needle plate position detection circuit applicable to the power-on reset of a flat knitting machine, as described in a specific implementation of this manual.
[0022] Figure 3 This is a schematic diagram of a processing unit for a needle plate position detection circuit applicable to power-on reset of a flat knitting machine, as described in a specific implementation of this manual.
[0023] Figure 4This is a schematic diagram of a Hall effect detection unit for a needle plate position detection circuit applicable to power-on reset of a flat knitting machine, as described in a specific implementation of this manual.
[0024] Figure 5 This is a schematic diagram of a power supply unit for a needle plate position detection circuit applicable to power-on reset of a flat knitting machine, as described in a specific implementation of this manual. Detailed Implementation
[0025] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.
[0026] In the following description, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The following description provides multiple embodiments of this application, which can be substituted or combined with each other. Therefore, this application can also be considered to include all possible combinations of the same and / or different embodiments described. Thus, if one embodiment includes features A, B, and C, and another embodiment includes features B and D, then this application should also be considered to include embodiments containing one or more other possible combinations of A, B, C, and D, even if such embodiments are not explicitly described in the following text.
[0027] The following description provides examples and does not limit the scope, applicability, or examples set forth in the claims. Changes may be made to the function and arrangement of the described elements without departing from the scope of this application. Various processes or components may be appropriately omitted, substituted, or added to the examples. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Furthermore, features described with respect to some examples may be combined into other examples.
[0028] Firstly, please refer to Figure 1 , Figure 1 This specification illustrates a schematic diagram of a needle plate position detection circuit suitable for power-on reset of a flat knitting machine, as provided in an embodiment of this specification.
[0029] like Figure 1As shown, the needle plate position detection circuit for power-on reset of a flat knitting machine includes two Hall sensors arranged around the needle plate drive motor. The two Hall sensors detect the rotation of the needle plate drive motor, thereby detecting the position of the needle plate. The needle plate position detection circuit also includes two Hall detection units, a processing unit, and a power supply unit. The Hall detection units are electrically connected to the Hall sensors, the processing unit is electrically connected to the Hall detection units, and the power supply unit is electrically connected to the processing unit. The Hall sensors convert the rotation information of the needle plate drive motor into a rotation signal and send it to the Hall detection units. After receiving the rotation signal, the Hall detection units send the rotation signal to the processing unit. The processing unit calculates the number of rotations of the needle plate drive motor when the flat knitting machine is powered off based on the rotation signal. The power supply unit provides energy to the needle plate position detection circuit when the flat knitting machine is powered off. In this application, a power supply unit is set up so that the entire needle plate position detection circuit can work when the knitting machine is powered off. A Hall sensor is set up to detect the rotation of the needle plate drive motor. After receiving the rotation signal, the Hall sensor sends the rotation signal to the processing unit. The processing unit calculates the number of rotations of the needle plate drive motor when the knitting machine is powered off based on the rotation signal. When the knitting machine is powered on again, the number of rotations of the needle plate drive motor calculated by the processing unit is fed back to the motor coding detection circuit. The motor coding detection circuit controls the motor to reach the specified position as needed by the motor drive circuit, thereby avoiding repeated zeroing correction and improving the operating efficiency of the knitting machine.
[0030] It should be noted that the "unit" in the motor coding detection circuit can be implemented by an analog circuit that performs the functions described in the embodiments of this application.
[0031] Furthermore, the angle formed by the two Hall sensors connected to the needle plate drive motor is a right angle. When the two Hall sensors are arranged with a 90° phase difference, the two output pulse signals have a phase difference: in forward rotation, phase A leads phase B by 90°; in reverse rotation, phase B leads phase A by 90°. If a single Hall sensor outputs N pulses per revolution, then two orthogonal Hall sensors can achieve a fourfold frequency multiplication (by detecting the combination of rising and falling edges). Each detected complete cycle (such as 4 edge changes) can be counted as 1 / N revolutions. Combined with direction information, the number of revolutions can be accumulated bidirectionally, avoiding counting errors caused by reverse rotation.
[0032] Specifically, the operating current of the needle plate position detection circuit is less than or equal to 2uA, thereby ensuring that the entire needle plate position detection circuit can be used for a long time.
[0033] In one possible implementation, the Hall detection unit includes a first capacitor C5, the first end of the first capacitor C5 being electrically connected to the first interface of the Hall sensor, and the second end of the first capacitor C5 being electrically connected to the second interface of the Hall sensor and the power supply unit.
[0034] Furthermore, the Hall detection unit also includes a second capacitor C6 and a first resistor R6. The first end of the first resistor R6 is electrically connected to the third interface of the Hall sensor, and the second end of the first resistor R6 is electrically connected to the first end of the second capacitor C6 and the processing unit. The second end of the second capacitor C6 is grounded. In the strong electromagnetic environment of a motor, the output signal of the Hall sensor is easily affected by switching noise, power supply ripple, and radio frequency interference. These interferences typically manifest as glitches, spikes, or high-frequency oscillations, which may be misinterpreted as valid edges, leading to counting errors or direction misjudgments. The second capacitor C6 and the first resistor R6 can attenuate high-frequency components while retaining useful low-frequency signals (such as the square wave edge of a Hall switch), improving the signal-to-noise ratio. The second capacitor C6 and the first resistor R6 smooth the rising / falling edges of the signal, avoiding multiple triggers in a short period, ensuring that each magnetic pole change produces only one clean transition, thereby eliminating signal jitter.
[0035] In one possible implementation, the power supply unit includes a battery, with the first end of the battery electrically connected to the Hall detection unit and the processing unit, and the second end of the battery grounded. Specifically, the battery is a 3V battery.
[0036] Furthermore, the power supply unit also includes a reverse protection diode D2. The first terminal of the reverse protection diode D2 is electrically connected to the Hall detection unit and the processing unit, and the second terminal of the reverse protection diode D2 is electrically connected to the battery. The reverse protection diode D2 only allows current to flow in the correct direction and is cut off in the reverse direction. If the positive and negative terminals are reversed due to human error, wiring error, or confusion of plug polarity, the reverse protection diode D2 will be cut off, thereby preventing the components of the pin plate position detection circuit from being damaged or burned out.
[0037] In one possible implementation, the processing unit includes an MCU. The first and second interfaces of the MCU are respectively connected to two Hall effect detection units. The third interface of the MCU is electrically connected to the first terminal of the second resistor R1. The fourth interface of the MCU is electrically connected to the first terminal of the third capacitor C1. The second terminal of the second resistor R1, the second terminal of the third capacitor C1, and the fifth interface of the MCU are grounded. The sixth interface of the MCU is electrically connected to the first terminal of the third resistor R2 and the first terminal of the fourth capacitor C2. The second terminal of the third resistor R2 is electrically connected to the power supply unit. The second terminal of the fourth capacitor C2 is grounded. The seventh interface of the MCU is electrically connected to the first terminal of the fourth resistor R3. The second terminal of the fourth resistor R3 is connected to a 3.3V voltage input. The eighth interface of the MCU is electrically connected to the first terminal of the first diode D1. The second terminal of the first diode D1 is electrically connected to the first terminal of the fifth resistor R4. The second terminal of the fifth resistor R4 is connected to a 3.3V voltage input. The ninth interface of the MCU is electrically connected to the first terminal of the sixth resistor R5. The second terminals of the first diode D1 and the second terminal of the sixth resistor R5 are electrically connected to the motor encoder detection circuit.
[0038] Those skilled in the art will clearly understand that the technical solutions of the embodiments of this application can be implemented by means of software and / or hardware. In this specification, "unit" and "module" refer to software and / or hardware that can independently complete or cooperate with other components to complete a specific function, wherein the hardware may be, for example, a field-programmable gate array (FPGA), an integrated circuit (IC), etc.
[0039] Each processing unit and / or module in the embodiments of this application can be implemented by an analog circuit that implements the functions described in the embodiments of this application, or by software that executes the functions described in the embodiments of this application.
[0040] Secondly, embodiments of this specification provide a needle plate position detection device suitable for power-on reset of a flat knitting machine, the needle plate position detection device being packaged with the needle plate position detection circuit as described in the first aspect.
[0041] Thirdly, embodiments of this specification provide a flat knitting machine, which includes the needle plate position detection device as described in the second aspect.
[0042] The foregoing description is merely an exemplary embodiment of this disclosure and should not be construed as limiting the scope of this disclosure. Any equivalent changes and modifications made in accordance with the teachings of this disclosure shall still fall within the scope of this disclosure. Those skilled in the art will readily conceive of embodiments of this disclosure upon considering the specification and practicing the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not described herein. The specification and embodiments are to be considered exemplary only, and the scope and spirit of this disclosure are defined by the claims.
Claims
1. A needle plate position detection circuit suitable for power-on reset of a flat knitting machine, characterized in that, The circuit includes two Hall sensors disposed around the needle plate drive motor, two Hall detection units electrically connected to the two Hall sensors, a processing unit electrically connected to the Hall detection units, and a power supply unit electrically connected to the processing unit. The two Hall sensors generate rotation signals when the needle plate drive motor rotates. After receiving the rotation signals, the two Hall detection units send the rotation signals to the processing unit. The processing unit calculates the number of rotations of the needle plate drive motor when the knitting machine loses power based on the rotation signals. The power supply unit is used to provide energy to the needle plate position detection circuit when the knitting machine loses power.
2. The needle plate position detection circuit for power-on reset of a flat knitting machine according to claim 1, characterized in that, The angle formed by the connection between the two Hall sensors and the needle plate drive motor is a right angle.
3. The needle plate position detection circuit for power-on reset of a flat knitting machine according to claim 1, characterized in that, The Hall detection unit includes a first capacitor, a first end of which is electrically connected to a first interface of the Hall sensor, and a second end of which is electrically connected to a second interface of the Hall sensor and the power supply unit.
4. A needle plate position detection circuit suitable for power-on reset of a flat knitting machine according to claim 3, characterized in that, The Hall detection unit further includes a second capacitor and a first resistor. The first end of the first resistor is electrically connected to the third interface of the Hall sensor, the second end of the first resistor is electrically connected to the first end of the second capacitor and the processing unit, and the second end of the second capacitor is grounded.
5. A needle plate position detection circuit suitable for power-on reset of a flat knitting machine according to claim 1, characterized in that, The power supply unit includes a battery, with the first end of the battery electrically connected to the Hall detection unit and the processing unit, and the second end of the battery grounded.
6. A needle plate position detection circuit suitable for power-on reset of a flat knitting machine according to claim 5, characterized in that, The power supply unit also includes an anti-reverse diode, the first end of which is electrically connected to the Hall detection unit and the processing unit, and the second end of which is electrically connected to the battery.
7. A needle plate position detection circuit suitable for power-on reset of a flat knitting machine according to claim 1, characterized in that, The processing unit includes an MCU. The first and second interfaces of the MCU are respectively connected to the two Hall effect detection units. The eighth interface of the MCU is electrically connected to the first terminal of the first diode. The ninth interface of the MCU is electrically connected to the first terminal of the sixth resistor. The second terminal of the first diode and the second terminal of the sixth resistor are electrically connected to the motor encoder detection circuit.
8. A needle plate position detection circuit suitable for power-on reset of a flat knitting machine according to claim 1, characterized in that, The operating current of the needle plate position detection circuit is less than or equal to 2uA.
9. A needle plate position detection device suitable for power-on reset of a flat knitting machine, characterized in that, The device is encapsulated with a needle plate position detection circuit as described in any one of claims 1-8.
10. A flat knitting machine, characterized in that, The flat knitting machine includes the needle plate position detection device as described in claim 9.