Electrostatic detection system

Abstract

The invention relates to the technical field related to electrostatic detection, in particular to an electrostatic detection system. The electrostatic detection system comprises an electrostatic detection probe, an oscillator, a phase-sensitive detector and a potential indicator, the electrostatic detection probe comprises a vibration arm, a vibration piece, an induction piece and an alternating current amplifier, and the alternating current amplifier is used for amplifying a voltage signal induced by the induction piece; the oscillator is used for generating an alternating-current signal with set frequency to drive the vibrating piece to vibrate; the frequency detection circuit is used for mixing and amplifying the voltage signal sensed by the sensing part, and the detection processing circuit is used for processing and outputting the mixed and amplified voltage signal. The electrostatic detection system can improve the resolution and sensitivity of electrostatic detection, is suitable for detecting tiny static electricity, can detect and display electrostatic voltage more accurately, and solves the problems that an electrostatic detection system in the prior art is low in detection resolution and poor in application scene.

Description

Technical Field

[0001] The present invention relates to the technical field related to electrostatic detection, and in particular to an electrostatic detection system. Background Art

[0002] Electrostatic sensors and / or electrostatic detection meters are special, precise instruments for monitoring static electricity on the surface of objects, and play a very important role in static electricity measurement and protection.

[0003] On electronics factory production lines, static electricity testing of products is crucial for protecting them from the hazards of electrostatic discharge and ensuring product quality. This is particularly true in the semiconductor industry, where miniaturization and sophistication are driving increasingly stringent requirements for static electricity detection, requiring extremely low levels of static electricity. This requires equipment capable of detecting even this low level of static electricity.

[0004] The static electricity detection system in the existing technology has low detection resolution and poor application scenarios, which makes it difficult to meet the needs of small static electricity detection. Summary of the Invention

[0005] An object of the present invention is to provide a static electricity detection system to improve the resolution of static electricity detection.

[0006] In order to solve the above technical problems, the present invention provides an electrostatic detection system.

[0007] The static electricity detection system of the present invention comprises a static electricity detection probe, an oscillator, a phase-sensitive detector and a potential indicator;

[0008] The electrostatic detection probe includes a vibrating arm, a vibrating member, a sensing member, and an AC amplifier. The vibrating member and the sensing member are arranged on the vibrating arm. The vibrating member is used to drive the vibrating arm to vibrate. The sensing member is used to sense static electricity. The AC amplifier is used to amplify the voltage signal sensed by the sensing member.

[0009] The oscillator is used to generate an AC signal of a set frequency to drive the vibrating element to vibrate;

[0010] The phase-sensitive detector is provided with a frequency detection circuit and a detection processing circuit, wherein the frequency detection circuit is used to mix and amplify the voltage signal sensed by the induction element, and the detection processing circuit is used to process and output the mixed and amplified voltage signal;

[0011] The potential indicator is used to receive the voltage signal output by the phase-sensitive detector and display the voltage.

[0012] Furthermore, a feedback coil is included, and the feedback coil is used to monitor the AC signal generated by the oscillator and feed back the AC signal to the oscillator.

[0013] Furthermore, the vibration arm comprises a first arm and a second arm which are arranged at intervals and have the same natural frequency. There are two vibration members, namely a first vibration member and a second vibration member. The first vibration member is arranged on the first arm, and the second vibration member is arranged on the second arm.

[0014] The induction component is arranged on the first arm and is used for inducing static electricity.

[0015] Furthermore, the oscillator is provided with a mechanical vibration circuit, which includes a self-excited oscillation circuit, a signal amplification and regulation part, and a signal processing and transportation part. The self-excited oscillation circuit is used to generate an oscillation signal, and the first vibrator is connected to the self-excited oscillation circuit as one of the input nodes of the self-excited oscillation circuit; the signal amplification and regulation part is used to amplify and process the oscillation signal, and output an AC signal after filtering out high-frequency noise; the signal output and transportation circuit is used to filter and perform secondary processing on the AC signal, and output the processed AC signal to the second vibrator.

[0016] Furthermore, the first vibrating member and the second vibrating member are piezoelectric ceramics.

[0017] Furthermore, the frequency detection circuit includes a signal amplification part, a transformer part, a signal processing part and a mixing output part. The signal amplification part is used to amplify the voltage signal, the transformer part is used to generate a local oscillator signal to mix with the voltage signal to generate a mixing signal, the signal processing part is used to filter the mixing signal and perform impedance matching, and the output part is used to output the processed mixing signal.

[0018] Furthermore, the frequency detection circuit further includes a voltage stabilization protection part, which is used to perform overvoltage protection on the circuit.

[0019] Furthermore, the detection processing circuit includes a signal coupling and adjustment part and a signal amplification and filtering part. The signal coupling and adjustment part is used to couple and amplify the voltage signal after mixing and amplification, and the signal amplification and filtering part is used to amplify and filter the voltage signal after coupling and amplification, and output the amplified and filtered voltage signal.

[0020] Furthermore, the detection processing circuit further includes a voltage zeroing part, and the voltage zeroing part is used to compensate for a DC error in the detection processing circuit.

[0021] Furthermore, the signal amplification and filtering part includes a first-stage operational amplifier circuit and a second-stage operational amplifier circuit, the first-stage operational amplifier circuit is used to perform first-stage amplification and first-stage filtering on the voltage signal, and the second-stage filtering part is used to perform second-stage amplification and second-stage filtering on the voltage signal.

[0022] Compared with the prior art, the present invention has at least the following beneficial effects:

[0023] The AC amplifier and phase-sensitive detector of the electrostatic detection system of the present application can improve the resolution and sensitivity of electrostatic detection, is suitable for the detection of tiny static electricity, and can more accurately detect and display electrostatic voltage, solving the problems of low detection resolution and poor applicability of electrostatic detection systems in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A system diagram of an embodiment of the static electricity detection system of the present invention;

[0025] Figure 2 for Figure 1 Circuit diagram of the AC amplifier circuit of the AC amplifier in the electrostatic detection system;

[0026] Figure 3 for Figure 1 A circuit diagram of a mechanical vibration circuit of an oscillator in an electrostatic detection system;

[0027] Figure 4 for Figure 1 Circuit diagram of the frequency detection circuit of the phase-sensitive detector in the electrostatic detection system;

[0028] Figure 5 for Figure 1 Circuit diagram of the detection processing circuit of the phase-sensitive detector in the electrostatic detection system. DETAILED DESCRIPTION

[0029] The following describes the electrostatic detection system of the present invention with reference to a schematic diagram, which illustrates a preferred embodiment of the present invention. It should be understood that those skilled in the art may modify the invention described herein while still achieving the beneficial effects of the invention. Therefore, the following description should be understood as a general guideline for those skilled in the art and is not intended to limit the present invention.

[0030] The serial numbers of the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings). In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0031] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0032] The present invention is described in more detail in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of the present invention will become more apparent from the following description and claims. It should be noted that the drawings are greatly simplified and not to exact scale, and are provided solely for the purpose of assisting in the description of the embodiments of the present invention.

[0033] The following is attached with the instruction manual Figure 1 To the attached Figure 5 , the electrostatic detection system of the present invention is introduced.

[0034] In some embodiments, such as Figure 1As shown, the electrostatic detection system of the present application includes an electrostatic detection probe, an oscillator, a phase-sensitive detector and a potential indicator. The electrostatic detection probe includes a vibrating arm, a vibrating member, an inductive member and an AC amplifier. The vibrating member and the inductive member are arranged on the vibrating arm. The vibrating member is used to drive the vibrating arm to vibrate, the inductive member is used to sense static electricity, and the AC amplifier is used to amplify the voltage signal sensed by the inductive member. The oscillator is used to generate an AC signal of a set frequency to drive the vibrating member to vibrate. A frequency detection circuit and a detection processing circuit are provided in the phase-sensitive detector. The frequency detection circuit is used to mix and amplify the voltage signal sensed by the inductive member, and the detection processing circuit is used to process and output the mixed and amplified voltage signal. The potential indicator is used to receive the voltage signal output by the phase-sensitive detector and display the voltage.

[0035] The AC amplifier of the electrostatic detection system of the present application can amplify the initially induced voltage signal, and the frequency detection circuit in the phase-sensitive detector can mix and amplify the amplified voltage signal, wherein, through the mixing process, the information related to the electrostatic characteristics of the charged body under test in the induced voltage signal (such as the signal frequency or amplitude change caused by the distance change, etc.) can be transferred to a new frequency component, generating a mixed signal containing multiple frequency components. This frequency transfer helps to transform the information in the original induced potential signal, which is weak and difficult to detect directly, into a frequency band that is easier to detect and process; since the initially induced voltage signal is usually very weak, it is not conducive to subsequent signal analysis and processing. The amplification process can enhance the amplitude of the voltage signal, making it easier for the subsequent circuit to accurately extract and analyze the information about the electrostatic condition of the charged body under test carried in the signal. The detection processing circuit in the phase-sensitive detector can process the mixed and amplified voltage signal to improve the signal output quality.

[0036] The AC amplifier and phase-sensitive detector of the electrostatic detection system of the present application can improve the resolution and sensitivity of electrostatic detection, is suitable for the detection of tiny static electricity, and can more accurately detect and display electrostatic voltage, solving the problems of low detection resolution and poor applicability of electrostatic detection systems in the prior art.

[0037] Furthermore, in some embodiments, Figure 2As shown, the AC amplifier includes an AC amplifier circuit, which includes a power supply, an operational amplifier U1, resistors R1 and R2, an input interface X3, and an output interface WP3. The power supply is a 9V power supply. The operational amplifier U1 is used to amplify the input signal and has characteristics such as high gain, high input impedance, and low output impedance. In this circuit, it is configured in an inverting amplification mode, amplifying the input signal and outputting it in an inverted state. Resistor R1 is an input resistor that connects the AC signal source input through input interface X3 to the inverting input of the operational amplifier U1. Resistor R2 is a feedback resistor connected between the output and inverting input of the operational amplifier to determine the gain and stabilize the output.

[0038] Specifically, during operation, the voltage signal sensed by the inductive element is input through the input interface X3, connected to the inverting input terminal of the operational amplifier U1 through the resistor R1, and the signal at the output terminal is fed back to the inverting input terminal through R2. The input voltage signal is amplified and inverted according to a predetermined amplification factor, and finally the amplified voltage signal is output from the WP3 output terminal of the operational amplifier U1 for use by subsequent circuits.

[0039] Furthermore, in some embodiments, the electrostatic detection system further includes a feedback coil, which is used to monitor the AC signal generated by the oscillator and feed back the AC signal to the oscillator.

[0040] The feedback coil enables the system to monitor the AC signal output by the oscillator in real time and adjust the oscillator's operating state through a feedback mechanism, thereby ensuring the stability and accuracy of the AC signal output by the oscillator. Specifically, the feedback coil can be placed at the output of the oscillator. It senses the AC signal output by the oscillator and feeds the sensed signal back to the oscillator's control circuit. The control circuit then adjusts the oscillator's output frequency and amplitude based on the feedback signal.

[0041] The setting of the feedback coil enables the oscillator to be dynamically adjusted according to the actual output signal, avoiding signal drift caused by changes in the external environment or device aging, thereby ensuring that the electrostatic detection system can operate stably under various working conditions and improving the detection accuracy and reliability of the system.

[0042] Furthermore, in some embodiments, the vibration arm has a first arm and a second arm that are arranged at intervals and have equal natural frequencies. There are two vibrating members, namely a first vibrating member and a second vibrating member. The first vibrating member is arranged on the first arm, and the second vibrating member is arranged on the second arm. The induction member is arranged on the first arm for inducing static electricity.

[0043] Specifically, the spacing of the first and second arms allows the vibrator to vibrate at different locations, thereby enhancing its ability to sense static electricity. The arrangement of the first and second vibrators further optimizes the vibration effect, allowing the sensor to more accurately capture static electricity signals.

[0044] Furthermore, in some embodiments, the first vibrating member and the second vibrating member are both piezoelectric ceramics. Piezoelectric ceramics are materials that exhibit a piezoelectric effect, generating mechanical vibrations when a voltage is applied, or generating a voltage signal when subjected to mechanical vibrations. This material selection enables the first vibrating member and the second vibrating member to efficiently convert electrical signals into mechanical vibrations, thereby driving the vibration of the vibrating arm.

[0045] Specifically, the piezoelectric effect of piezoelectric ceramics is achieved through the asymmetry of their internal crystal structure. When voltage is applied, the crystals within the piezoelectric ceramic deform, generating mechanical vibrations. This vibration is transmitted to the vibrating arm via the first and second vibrating members, which in turn drives the vibration of the vibrating arm. Due to the high sensitivity and fast response of piezoelectric ceramics, they can effectively improve the detection accuracy and response speed of electrostatic detection systems.

[0046] As a preferred embodiment, the piezoelectric ceramic can be made of lead zirconate titanate, a material with a high piezoelectric constant and mechanical quality factor, providing stronger vibration output and more stable performance. Furthermore, the shape and size of the piezoelectric ceramic can be designed based on actual needs, such as circular, square, or rectangular shapes, to meet the needs of different application scenarios.

[0047] Furthermore, in some embodiments, the oscillator is provided with a mechanical vibration circuit, which includes a self-excited oscillation circuit portion, a signal amplification and regulation portion, and a signal processing and transport circuit. The self-excited oscillation circuit is used to generate an oscillation signal, and the first vibrator is connected to the self-excited oscillation circuit as one of the input nodes of the self-excited oscillation circuit; the signal amplification and regulation portion is used to amplify and process the oscillation signal and output an AC signal after filtering out high-frequency noise; the signal output and transport circuit is used to filter and perform secondary processing on the AC signal and output the processed AC signal to the second vibrator. The oscillator can be powered by a 9V power supply.

[0048] The self-excited oscillation circuit uses the first vibrating element as one of its input nodes to effectively generate an oscillation signal. The signal amplification and conditioning section amplifies and processes the oscillation signal, ensuring that the output AC signal is free of high-frequency noise and improved signal purity. The signal processing and transmission circuit further filters and performs secondary processing on the AC signal, ensuring the final output AC signal is of higher quality and capable of more stably driving the second vibrating element.

[0049] Specifically, if Figure 3 As shown, the self-excited oscillation circuit includes an operational amplifier A3-C and its surrounding resistors R14, R18, C27, R19 and C29, wherein resistor R14 is a feedback resistor used to set the gain and feedback mechanism of the operational amplifier, and the non-inverting input terminal is connected to the interface WP6, which is used to connect the first vibrator, and the first vibrator works together with the circuit to generate an oscillation signal.

[0050] Resistor R18, capacitor C27, and resistor R19 form an RC filter circuit that adjusts the frequency and phase characteristics of the signal input to operational amplifier A3-C, ensuring that the circuit meets the phase conditions for self-oscillation. Capacitor C29 is used for AC coupling to further adjust the phase and prevent DC components from affecting the circuit's oscillation.

[0051] The signal amplification and conditioning section includes an operational amplifier A3-A, an adjustable resistor P2, resistors R15, R31, R28, and capacitor C34. Operational amplifier A3-A amplifies the signal from the self-oscillation circuit input via resistor R15. Resistor R31 is a feedback resistor that determines the amplification factor of operational amplifier A3-A. The output of operational amplifier A3-A is connected to adjustable resistor P2, which can be adjusted to adjust the amplitude of the output signal to obtain a suitable drive voltage. Resistor R28 and capacitor C34 form a low-pass filter to filter out high-frequency noise and smooth the output AC signal.

[0052] The signal processing and transmission circuit includes transistors Q1 and Q2, operational amplifiers A3-B and A3-D, and related components. Specifically, transistor Q1, along with resistors R29 and R30, forms a switching circuit. The processed signal drives the base of transistor Q1, controlling its on and off states and converting the amplified AC signal into a pulse signal suitable for subsequent processing. Transistor Q2 further amplifies or buffers the signal, improving its drive capability for output to the DATA interface.

[0053] Operational amplifier A3-B works in conjunction with resistor R22, Zener diodes ZD4 and D6, and capacitor C30. Operational amplifier A3-B is used to rectify the input AC signal and control charging. Zener diode ZD4 provides a stable reference voltage, capacitor C30 stores charge, and Zener diode D6 rectifies, allowing only unidirectional current.

[0054] Operational amplifier A3-D, resistor R12, resistor R13, capacitor C22, capacitor C23, etc. form a signal processing circuit, which further processes the rectified signal to stabilize the oscillation frequency. Zener diode D5 plays a rectifying role.

[0055] The signal processing and transmission circuit transmits the processed driving signal to the second vibrating element through the WP5 interface, so that the second vibrating element drives the second arm to vibrate.

[0056] The technical solution of this application achieves precise control and efficient processing of the oscillation signal through the design of a mechanical vibration circuit, solving the problems of unstable oscillation signals and large noise interference in the prior art, and can provide a more stable and purer AC signal, thereby improving the overall performance and reliability of the electrostatic detection system.

[0057] In some embodiments, the frequency detection circuit includes a signal amplification part, a transformer part, a signal processing part and a mixing output part. The signal amplification part is used to amplify the voltage signal, the transformer part is used to generate a local oscillator signal to mix with the voltage signal to generate a mixing signal, the signal processing part is used to filter the mixing signal and perform impedance matching, and the output part is used to output the processed mixing signal.

[0058] Specifically, if Figure 4 As shown, the frequency detection circuit also includes a low-pass filter circuit consisting of resistor R7, capacitors C12 and C13. Capacitors C12 and C13 can suppress stray signals of different frequencies, allowing the low-pass filter circuit to ensure that only sensor signals within a specific frequency band (mainly low-frequency useful signals) can pass smoothly, preparing for subsequent hybrid amplification.

[0059] The signal amplification section includes operational amplifier A1, resistor R4, capacitors C31, and capacitor C32. In addition to receiving the voltage signal, operational amplifier A1 also receives a local oscillator signal generated by transformer T1 and other related components. The frequency of the local oscillator signal is known and stable. These two signals are mixed within operational amplifier A1 and then amplified based on the parameters of external feedback components such as resistor R4. By mixing the local oscillator signal with the sensor signal, the sensor signal, which originally only carries the measured information, undergoes frequency or phase changes consistent with detection rules, facilitating the subsequent extraction and processing of specific frequency components.

[0060] Furthermore, the power supply of operational amplifier A1 is decoupled via capacitors C31 and C32. Power supply VCC-9V is a DC power source that provides energy for the normal operation of operational amplifier A1. Capacitors C31 and C32 filter out high-frequency noise on the power line, ensuring that operational amplifier A1 receives a stable and pure DC power supply. This stabilizes A1's performance and is unaffected by power supply fluctuations, thereby ensuring the accuracy and reliability of signal mixing and amplification.

[0061] The transformer section includes transformer T1, which generates and transmits the local oscillator signal. It produces a local oscillator signal with a stable frequency and appropriate amplitude, and couples this signal to operational amplifier A1 for mixing. The local oscillator signal mixes with the voltage signal to produce a mixed signal. This mixed signal contains multiple frequency components, including detection target signals such as difference and sum frequency signals related to the measured quantity. Subsequent circuits extract and process these signals.

[0062] The presence of transformer T1 also electrically isolates the front and rear circuits, reducing mutual interference during signal transmission and improving signal purity and circuit stability.

[0063] The signal processing section and mixing output section include capacitor C1, resistor R3, capacitor C16, and resistor R10. C1 and R3 form one RC network, while C16 and R10 form another RC network. These networks sequentially process the mixed signal after hybrid amplification and transformer transmission. First, there is the filtering function. The RC network determines the cutoff frequency based on its parameters (the values of resistor R and capacitor C), filtering out unwanted high-frequency or low-frequency spurious signals in the mixed signal, making the output signal purer. Second, there is the impedance matching function, which adjusts the impedance during signal transmission to ensure the highest power transmission efficiency when the signal is transmitted from the current circuit module to the subsequent circuit module, reducing signal reflections and losses.

[0064] The frequency detection circuit also includes a voltage stabilization protection section for overvoltage protection of the circuit. This section includes Zener diodes ZD1 and ZD3. When excessive forward or reverse voltages appear in the mixed signal during transmission, Zener diodes ZD1 and ZD3 quickly conduct, clamping the voltage to near their regulated values. This prevents excessive voltage from damaging subsequently connected circuit components or devices, thus providing circuit overvoltage protection.

[0065] The mixed signal after filtering, impedance matching and voltage regulation protection is finally output through the GND-S port.

[0066] In some embodiments, the detection processing circuit includes a signal coupling and adjustment part, a signal amplification and filtering part, and a signal output part. The signal coupling and adjustment part is used to couple and amplify the voltage signal after mixing and amplification, and the signal amplification and filtering part is used to amplify and filter the voltage signal after coupling and amplification, and output the amplified and filtered voltage signal.

[0067] Specifically, if Figure 5 As shown, the signal coupling and adjustment part includes capacitor C12, field effect transistor Q4, resistor R12, voltage regulator diode D2 and adjustable resistor P3. The capacitor C12 is a coupling capacitor used to isolate the DC component in the input DATA signal path and only allow AC signals to pass through, avoiding the influence of DC bias on subsequent circuits and allowing subsequent circuits to focus on processing the AC change part of the signal.

[0068] Field effect transistor Q4, resistor R12 and Zener diode D2 form an amplifier circuit. The circuit composed of resistor R12 and Zener diode D2 provides a suitable bias voltage for field effect transistor Q4, so that it operates in a specific linear region, thereby amplifying the signal and enhancing the signal driving capability.

[0069] The adjustable resistor P3 is used to adjust the upper threshold value or gain-related parameters of the circuit. Specifically, by changing the resistance value of the adjustable resistor P3, the output characteristics of the amplifier circuit where the field effect transistor Q4 is located can be adjusted, such as adjusting the upper limit of the amplitude of the output signal.

[0070] In one embodiment, the detection processing circuit further includes a voltage zeroing portion, which is used to compensate for DC errors in the detection processing circuit. The voltage zeroing portion includes a voltage zeroing potentiometer P9, resistors R2, and resistors R3, which can provide an adjustable DC bias voltage for the subsequent operational amplifier, used to perform voltage zeroing on the entire signal processing chain, eliminate DC errors in the system, and ensure output accuracy. Resistors R2 and R3 act as voltage dividers, and the voltage value after voltage division can be changed by adjusting the sliding end position of the voltage zeroing potentiometer P9.

[0071] In one embodiment, the signal amplification and filtering part includes a first-stage operational amplifier circuit and a second-stage operational amplifier circuit. The first-stage operational amplifier circuit is used to perform a first-stage amplification and a first-stage filtering on the voltage signal, and the second-stage filtering part is used to perform a second-stage amplification and a second-stage filtering on the voltage signal.

[0072] Specifically, the first-stage op amp circuit includes an operational amplifier A1-A, resistors R1, R7, R8, R9, capacitors C4, and C5, which together constitute an active filtering and amplification circuit. Resistors R7, R8, and R9 form a feedback network for setting the gain of the amplifier, and capacitors C4 and C5 participate in filtering, selecting signals of different frequencies to improve signal purity.

[0073] The second-stage op amp circuit includes operational amplifiers A1-B, resistors R4, R5, R10, capacitors C6, and C9, which together form an active filtering and amplification circuit to further amplify and filter the voltage signal, thereby improving the amplitude and quality of the signal.

[0074] The interface WP18 of the signal amplification and filtering part serves as the voltage display output terminal. The signal after two-stage amplification and filtering is output to the potential indicator through the connector J2 for voltage display.

[0075] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. An electrostatic detection system, characterized in that: It includes an electrostatic detection probe, an oscillator, a phase-sensitive detector and a potential indicator; The electrostatic detection probe includes a vibrating arm, a vibrating member, a sensing member, and an AC amplifier. The vibrating member and the sensing member are arranged on the vibrating arm. The vibrating member is used to drive the vibrating arm to vibrate. The sensing member is used to sense static electricity. The AC amplifier is used to amplify the voltage signal sensed by the sensing member. The oscillator is used to generate an AC signal of a set frequency to drive the vibrating element to vibrate; The phase-sensitive detector is provided with a frequency detection circuit and a detection processing circuit, wherein the frequency detection circuit is used to mix and amplify the voltage signal sensed by the induction element, and the detection processing circuit is used to process and output the mixed and amplified voltage signal; The potential indicator is used to receive the voltage signal output by the phase-sensitive detector and display the voltage.

2. The static electricity detection system according to claim 1, characterized in that: It also includes a feedback coil, which is used to monitor the AC signal generated by the oscillator and feed it back to the oscillator.

3. The static electricity detection system according to claim 1, wherein: The vibration arm comprises a first arm and a second arm which are spaced apart and have the same natural frequency. There are two vibration members, namely a first vibration member and a second vibration member. The first vibration member is arranged on the first arm, and the second vibration member is arranged on the second arm. The induction component is arranged on the first arm and is used for inducing static electricity.

4. The static electricity detection system according to claim 3, characterized in that: The oscillator is provided with a mechanical vibration circuit, which includes a self-excited oscillation circuit, a signal amplification and regulation part, and a signal processing and transportation part. The self-excited oscillation circuit is used to generate an oscillation signal. The first vibrator is connected to the self-excited oscillation circuit and serves as one of the input nodes of the self-excited oscillation circuit; the signal amplification and regulation part is used to amplify and process the oscillation signal and output an AC signal after filtering out high-frequency noise; the signal output and transportation circuit is used to filter and perform secondary processing on the AC signal, and output the processed AC signal to the second vibrator.

5. The static electricity detection system according to claim 3, characterized in that: The first vibrating element and the second vibrating element are piezoelectric ceramics.

6. The static electricity detection system according to claim 1, characterized in that: The frequency detection circuit includes a signal amplification part, a transformer part, a signal processing part and a mixing output part. The signal amplification part is used to amplify the voltage signal, the transformer part is used to generate a local oscillation signal to mix with the voltage signal to generate a mixing signal, the signal processing part is used to filter the mixing signal and perform impedance matching, and the output part is used to output the processed mixing signal.

7. The static electricity detection system according to claim 6, characterized in that: The frequency detection circuit further includes a voltage stabilization protection part, which is used to perform overvoltage protection on the circuit.

8. The static electricity detection system according to claim 1, characterized in that: The detection processing circuit includes a signal coupling and adjustment part and a signal amplification and filtering part. The signal coupling and adjustment part is used to couple and amplify the voltage signal after mixing and amplification. The signal amplification and filtering part is used to amplify and filter the voltage signal after coupling and amplification, and output the amplified and filtered voltage signal.

9. The static electricity detection system according to claim 8, characterized in that: The detection processing circuit further includes a voltage zeroing part, which is used to compensate for a DC error in the detection processing circuit.

10. The static electricity detection system according to claim 8, characterized in that: The signal amplification and filtering part includes a first-stage operational amplifier circuit and a second-stage operational amplifier circuit. The first-stage operational amplifier circuit is used to perform a first-stage amplification and a first-stage filtering on the voltage signal, and the second-stage filtering part is used to perform a second-stage amplification and a second-stage filtering on the voltage signal.

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