A control method for a magnetic proximity sensor

Abstract

The present application relates to the technical field of magnetic proximity sensor, and particularly relates to a control method for a magnetic proximity sensor. Before judging whether the dry reed detection circuit outputs a second valid signal, it is judged whether the signal output ends of the N-pole collection unit and the S-pole collection unit both collect a first valid signal, that is, only when the first valid signal is collected, a driving signal is sent to the dry reed detection circuit, and only when both detections meet the conditions, a control signal for controlling execution is sent. The two detections are combined to serve as the judgment basis of the system, which can effectively improve the recognition detection stability and avoid misjudgment and misdetection caused by environmental changes such as electromagnetic interference.

Description

Technical Field

[0001] This invention relates to the field of magnetic proximity sensor technology, and more particularly to a control method for magnetic proximity sensors. Background Technology

[0002] Magnetic proximity sensors are commonly used in industrial machinery and automated production lines for functions such as limit protection and positioning monitoring. Magnetic proximity sensors utilize the proximity of a magnetic object to drive a reed switch, outputting high or low level signals based on the reed switch's on / off state. However, these magnetic proximity sensors cannot detect external electromagnetic interference or environmental changes in the sensing element, leading to false alarms and potential safety hazards during use. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a control method for magnetic proximity sensors that can effectively avoid misjudgment and false detection caused by environmental changes such as electromagnetic interference.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0005] A control method for a magnetic proximity sensor includes the following steps:

[0006] S1. Collect the signal output terminals of the N-pole acquisition unit and the S-pole acquisition unit, and determine whether the first valid signal has been collected in both.

[0007] S2. If the first valid signal is collected, a drive signal is sent to the reed switch detection circuit, and then it is determined whether the reed switch detection circuit outputs the second valid signal.

[0008] S3. If the reed switch detection circuit outputs a second valid signal, then a control signal for controlling execution is issued.

[0009] The beneficial effects of this invention are as follows:

[0010] This invention provides a control method for a magnetic proximity sensor. Before determining whether the reed switch detection circuit outputs a second valid signal, it first determines whether the signal output terminals of both the N-pole and S-pole acquisition units have acquired a first valid signal. That is, a drive signal is sent to the reed switch detection circuit only when both first valid signals are acquired. Furthermore, a control signal for execution is issued only when both detection conditions are met. By using a combination of these two detection methods as the system's judgment criteria, the stability of the identification and detection can be effectively improved, avoiding misjudgments and false detections caused by environmental changes such as electromagnetic interference. Attached Figure Description

[0011] Figure 1This is a flowchart illustrating the steps of a control method for a magnetic proximity sensor according to the present invention.

[0012] Figure 2 This is a circuit diagram of a control method for a magnetic proximity sensor according to the present invention.

[0013] Figure 3 This is a circuit diagram of the N and S pole magnetic detection of a control method for a magnetic proximity sensor according to the present invention.

[0014] Figure 4 This is a circuit diagram of a DC-DC power supply for a circuit section corresponding to a control method for a magnetic proximity sensor according to the present invention. Detailed Implementation

[0015] To explain in detail the technical content, objectives, and effects of the present invention, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0016] Please refer to Figures 1 to 4 The present invention provides a control method for a magnetic proximity sensor, comprising the following steps:

[0017] S1. Collect the signal output terminals of the N-pole acquisition unit and the S-pole acquisition unit, and determine whether the first valid signal has been collected in both.

[0018] S2. If the first valid signal is collected, a drive signal is sent to the reed switch detection circuit, and then it is determined whether the reed switch detection circuit outputs the second valid signal.

[0019] S3. If the reed switch detection circuit outputs a second valid signal, then a control signal for controlling execution is issued.

[0020] As can be seen from the above description, the beneficial effects of the present invention are as follows:

[0021] This invention provides a control method for a magnetic proximity sensor. Before determining whether the reed switch detection circuit outputs a second valid signal, it first determines whether the signal output terminals of both the N-pole and S-pole acquisition units have acquired a first valid signal. That is, a drive signal is sent to the reed switch detection circuit only when both first valid signals are acquired. Furthermore, a control signal for execution is issued only when both detection conditions are met. By combining two detection methods as the system's judgment criteria, the stability of identification and detection can be effectively improved, avoiding misjudgments and false detections caused by environmental changes such as electromagnetic interference.

[0022] Furthermore, step S1 specifically includes:

[0023] Simultaneously, the signal output terminals of the N-pole acquisition unit and the S-pole acquisition unit are collected, and it is determined whether the signal output terminals of the N-pole acquisition unit and the S-pole acquisition unit have both collected the first valid signal within the same time period.

[0024] As can be seen from the above description, the above judgment can effectively improve the recognition accuracy.

[0025] Furthermore, step S2 also includes:

[0026] If the signal output terminals of the N-pole acquisition unit and the S-pole acquisition unit fail to acquire the first valid signal within the same time period, a first abnormal signal is sent to the status display unit.

[0027] Determine whether an abnormal reset signal has been received. If so, stop sending the first abnormal signal to the status display unit.

[0028] As described above, the signals displayed by the status display unit can indicate the current status of the device and enable timely manual reset operations to avoid affecting normal use.

[0029] Furthermore, step S2 also includes:

[0030] If no abnormal reset signal is received, the system will repeatedly check whether an abnormal reset signal has been received after a preset time interval.

[0031] Furthermore, step S3 also includes:

[0032] If the reed switch detection circuit does not output a second valid signal, a second abnormal signal is sent to the status display unit, and the system checks again whether the reed switch detection circuit outputs a second valid signal.

[0033] As described above, the status of the device can be determined by the signal displayed by the status display unit, and the display will stop only when the reed switch detection circuit outputs a second valid signal.

[0034] Please refer to Figures 1 to 4 Embodiment 1 of the present invention is as follows:

[0035] like Figure 1 As shown, the present invention provides a control method for a magnetic proximity sensor, comprising the following steps:

[0036] S1. Collect the signal output terminals of the N-pole acquisition unit and the S-pole acquisition unit, and determine whether the first valid signal is collected in both; the first valid signal is a high-level signal.

[0037] Step S1 is as follows:

[0038] Simultaneously, the signal outputs of the N-pole acquisition unit and the S-pole acquisition unit are collected, and it is determined whether the signal outputs of both units acquire the first valid signal within the same time period. In this implementation, the time period can be set according to actual needs.

[0039] S2. If the first valid signal is collected, a drive signal is sent to the reed switch detection circuit, and then it is determined whether the reed switch detection circuit outputs a second valid signal; wherein, the drive signal is a low-level signal.

[0040] Step S2 also includes:

[0041] If the signal output terminals of the N-pole acquisition unit and the S-pole acquisition unit fail to acquire the first valid signal within the same time period, a first abnormal signal is sent to the status display unit; wherein, the first abnormal signal is used to control the LED of the status display unit to remain constantly lit.

[0042] The system checks whether an abnormal reset signal has been received. If so, it stops sending the first abnormal signal to the status display unit. If no abnormal reset signal has been received, the system checks again after a preset time interval.

[0043] S3. If the reed switch detection circuit outputs a second valid signal, then a control signal for controlling execution is issued.

[0044] Step S3 also includes:

[0045] If the reed switch detection circuit does not output a second valid signal, a second abnormal signal is sent to the status display unit, and the system checks again whether the reed switch detection circuit outputs a second valid signal. The display stops only when the reed switch detection circuit outputs a second valid signal. The second abnormal signal is used to control the LED of the status display unit to flash.

[0046] It should be noted that all electronic components used in this embodiment are existing products.

[0047] The control circuit developed based on the control method for the magnetic proximity sensor described above is as follows:

[0048] The control circuit consists of a DC-DC power supply unit, a control chip, a reed switch circuit electrically connected to the control chip, a magnetic acquisition circuit electrically connected to the control chip, a status display unit electrically connected to the control chip, and a reset unit electrically connected to the control chip.

[0049] The control chip has at least six signal input / output pins; in this embodiment, only six pins are required.

[0050] like Figure 4 As shown, the DC-DC power supply unit consists of a step-down chip U2, a resistor R1, a diode D1, and capacitors C1 to C3. Figure 4 Connect the circuit to convert the 24V input into a stable VCC power output for use in subsequent units.

[0051] The magnetic acquisition circuit is electrically connected to the input terminal of the control chip. The magnetic acquisition circuit includes an N-pole acquisition unit and a S-pole acquisition unit, which are respectively electrically connected to the input terminal of the control chip.

[0052] Specifically, such as Figure 3 As shown, the N-pole acquisition unit includes an N-pole magnetic sensing device Q1 and a capacitor C5. The N-pole magnetic sensing device Q1 and the capacitor C5 are connected in parallel. One end of the parallel connection is electrically connected to the power supply VCC of the peripheral device, and the other end is grounded. The output terminal of the N-pole magnetic sensing device Q1 is electrically connected to the input terminal (IO1 pin) of the control chip.

[0053] The S-pole acquisition unit includes an S-pole magnetic sensing device Q2 and a capacitor C6. The S-pole magnetic sensing device Q2 and the capacitor C6 are connected in parallel. One end of the parallel connection is electrically connected to the power supply VCC of the peripheral device, and the other end is grounded. The output terminal of the S-pole magnetic sensing device Q2 is electrically connected to the input terminal (IO2 pin) of the control chip.

[0054] like Figure 2 As shown, the reed switch circuit includes an isolation chip U3, resistors R4 and R5, diode D4, fuse F1, resistor R2, and field-effect transistor Q3. The isolation chip U3 is an optocoupler chip. One end of the isolation chip U3 is electrically connected to the output terminal (IO3 pin) of the control chip, and the other end of the isolation chip U3 is electrically connected to one end of the reed switch. The other end of the reed switch is electrically connected to the input terminal (IO4 pin) of the control chip.

[0055] One end of the resistor R4 is electrically connected to the power supply VCC of the peripheral device, the other end of the resistor R4 is electrically connected to the first pin of one end of the optocoupler chip, and the second pin of one end of the optocoupler chip is electrically connected to the output terminal (IO3 pin) of the control chip.

[0056] The first pin of the other end of the optocoupler chip is electrically connected to one end of a reed switch S2. The other end of the reed switch S2 is electrically connected to the 24V power supply of the peripheral device through a resistor R5. The other end of the reed switch S2 is electrically connected to the negative terminal of a diode D4, and the positive terminal of the diode D4 is grounded. The second pin of the other end of the optocoupler chip is grounded through a fuse F1. The other end of the reed switch S2 is electrically connected to the drain of a field-effect transistor Q3. The gate of the field-effect transistor Q3 and one end of a resistor R2 are both electrically connected to the power supply VCC of the peripheral device. The source of the field-effect transistor Q3 and the other end of a resistor R2 are both electrically connected to the input terminal (IO4 pin) of the control chip.

[0057] When both the N and S poles detect a signal (i.e., both IO1 and IO2 pins are high), the output of the control chip (IO3 pin) provides a low level to the second pin of one end of the optocoupler chip. At this time, when the reed switch S2 detects a signal (i.e., S2 is high), it triggers the optocoupler chip to conduct, providing a high level to the input of the control chip (IO4 pin). The control chip then determines that the identification is complete; otherwise, it determines that there is an abnormality.

[0058] like Figure 2 As shown, the status display unit is electrically connected to the output terminal (IO5 pin) of the control chip. The status display unit includes a light-emitting diode (LED) D2 and a resistor R3; the cathode of LED D2 is electrically connected to the output terminal of the control chip, the anode of LED D2 is electrically connected to one end of resistor R3, and the other end of resistor R3 is electrically connected to the power supply VCC of the peripheral device. The state of LED D2 indicates whether an abnormal situation has occurred in the current circuit; for example, LED D2 displays red when there is an abnormality and green when it is normal.

[0059] like Figure 2 As shown, the reset unit includes a reset switch S1; one end of the reset switch S1 is electrically connected to the output terminal of the control chip, and the other end of the reset switch S1 is grounded. The system can be reset through the reset switch S1.

[0060] Working principle:

[0061] The power input is generated by the DC-DC power supply module, which produces the internal operating voltage. The magnetic pole acquisition circuit collects the received magnetic pole signal and inputs it to the MCU. The MCU logic determines that the magnetic pole signal is triggered and that the polarity matches the preset value, triggering the output circuit to output a signal, i.e., IO3 outputs a low level. The output signal drives and acquires the reed switch input. When the reed switch has input, it is at a high level, which in turn triggers the optocoupler chip to conduct, providing a high level to the input terminal (IO4 pin) of the control chip. When the magnetic pole detection signal or the reed switch signal is abnormal, an abnormal alarm is issued. The circuit returns to normal after a power-off restart or a reset signal is triggered.

[0062] The specific circuit diagram is as follows:

[0063] DC-DC power supply circuit: Features input power supply connection error prevention protection, power filtering, and internal U2 voltage regulation. Q1 / Q2 detect N / S polarity, U3 introduces signal detection and logic operations. When the polarity signal is incorrect, D2 remains constantly lit as an alarm indicator. When the judgment result is correct, U3 outputs the signal, acquiring the signal from reed switch S2 and outputting it. F1 provides output protection, and the output status is simultaneously fed back to the MCU via Q3. The MCU performs logic operations, and if the output result is incorrect, D2 sends a flashing indicator signal. When the constantly lit or flashing state of D2 is abnormal, S1 resets it, restoring it to the normal state. This product has self-diagnostic, reset, and signal output functions, detects matching targets, and has accurate polarity identification capabilities.

[0064] In summary, the control method for a magnetic proximity sensor provided by this invention determines whether both the N-pole and S-pole acquisition units have acquired a first valid signal before judging whether the reed switch detection circuit outputs a second valid signal. That is, a drive signal is sent to the reed switch detection circuit only when both first valid signals are acquired. Furthermore, a control signal for execution is issued only when both detection conditions are met. By using a combination of two detection methods as the system's judgment criteria, the stability of identification and detection can be effectively improved, avoiding misjudgments and false detections caused by environmental changes such as electromagnetic interference.

[0065] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A control method for a magnetic proximity sensor, characterized in that, Includes the following steps: S1. Collect the signal output terminals of the N-pole acquisition unit and the S-pole acquisition unit, and determine whether the first valid signal has been collected in both. S2. If the first valid signal is collected, a drive signal is sent to the reed switch detection circuit, and then it is determined whether the reed switch detection circuit outputs the second valid signal. S3. If the reed switch detection circuit outputs a second valid signal, then a control signal for controlling execution is issued.

2. The control method for a magnetic proximity sensor according to claim 1, characterized in that, Step S1 is as follows: Simultaneously, the signal output terminals of the N-pole acquisition unit and the S-pole acquisition unit are collected, and it is determined whether the signal output terminals of the N-pole acquisition unit and the S-pole acquisition unit have both collected the first valid signal within the same time period.

3. The control method for a magnetic proximity sensor according to claim 2, characterized in that, Step S2 also includes: If the signal output terminals of the N-pole acquisition unit and the S-pole acquisition unit fail to acquire the first valid signal within the same time period, a first abnormal signal is sent to the status display unit. Determine whether an abnormal reset signal has been received. If so, stop sending the first abnormal signal to the status display unit.

4. The control method for a magnetic proximity sensor according to claim 3, characterized in that, Step S2 also includes: If no abnormal reset signal is received, the system will repeatedly check whether an abnormal reset signal has been received after a preset time interval.

5. The control method for a magnetic proximity sensor according to claim 1, characterized in that, Step S3 also includes: If the reed switch detection circuit does not output a second valid signal, a second abnormal signal is sent to the status display unit, and the system checks again whether the reed switch detection circuit outputs a second valid signal.

Images