Ionization electrostatic detection apparatus standard decay time verification device and method

Abstract

The application discloses an ionized electrostatic detection equipment standard decay time verification device and method, which comprises an equipment host, a metal test plate, a hand-tightened metal self-checking screw, an RC discharge circuit, a standard resistor and a standard capacitor, the standard resistor and the standard capacitor are connected in series to form the RC discharge circuit, the metal test plate comprises an upper metal plate, an insulating plate and a glass fiber plate, a metal nut is embedded in the glass fiber plate, a second mounting hole is arranged on the rear shell of the equipment host, when the hand-tightened metal self-checking screw is screwed into the second mounting hole, the equipment host is normally detected, and the RC discharge circuit is in an open state; when the hand-tightened metal self-checking screw is screwed into the first mounting hole, the equipment host performs decay time verification, the standard resistor and the standard capacitor are conducted, and the RC discharge circuit is closed; and the equipment decay detection precision self-checking is realized.

Description

Technical Field

[0001] This invention relates to the field of decay time verification, and in particular to a standard decay time verification device and method for ionization electrostatic detection equipment. Background Technology

[0002] Under IEC and GB / T standards, electrostatic decay time is defined as the time required to decay 1000V voltage to 100V. However, there are currently no corresponding verification methods for how to verify the decay time or prove the standardization of the testing equipment. Therefore, it is necessary to invent an accurate decay time circuit and a structural device for easy verification on the equipment. Summary of the Invention

[0003] To overcome the above-mentioned shortcomings, the present invention aims to provide an ionization electrostatic detection device and method with a standard decay time, an RC discharge decay curve conforming to IEC and GB / T standards, and a built-in decay time verification structure.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a standard decay time verification device for ionization electrostatic detection equipment, comprising a main unit, a metal test plate, a hand-tightened metal self-test screw, and an RC discharge circuit. The metal test plate is disposed on the top of the main unit. The RC discharge circuit includes a standard resistor of 100GΩ±1% and a standard capacitor of 22pF±1%, which are connected in series to form the RC discharge circuit. The metal test plate includes an upper metal plate, an insulating plate, and a fiberglass plate arranged sequentially from top to bottom. A metal nut is embedded in the fiberglass plate. A plastic insulating pad is disposed below the metal test plate. The standard resistor is installed at the bottom of the plastic insulating pad. The lower end of the metal nut extends into the standard resistor at the bottom of the plastic insulating pad and is electrically connected to one end of the standard resistor. The upper metal plate and the insulating plate are each provided with through holes corresponding to the holes of the metal nut. The two through holes and the metal nut form a first mounting hole. A second mounting hole is provided on the rear shell of the main unit. One of the first mounting hole and the second mounting hole can be used to install the hand-tightened metal self-test screw.

[0005] When the hand-tightened metal self-test screw is screwed into the second mounting hole, the main unit of the equipment is tested normally, the RC discharge loop is in the open state, and the detection loop impedance of the main unit of the equipment is greater than 1000GΩ.

[0006] When the hand-tightened metal self-test screw is screwed into the first mounting hole, the hand-tightened metal self-test screw makes conductive contact with the metal nut, the main unit of the device performs attenuation time verification, the standard resistor and standard capacitor are connected, the RC discharge circuit is closed, the standard capacitor is initially charged with 1000V, and discharged to 100V to obtain the theoretical attenuation time t, realizing the self-verification of the device's attenuation detection accuracy.

[0007] Preferably, the theoretical decay time t is 5.06572s.

[0008] Preferably, a grounding metal plate is disposed below the plastic insulating pad, and one end of the standard resistor is connected to the grounding metal plate below.

[0009] Preferably, the end face of the fiberglass board facing the insulating board is plated with a metal layer.

[0010] Preferably, the length and width dimensions of the fiberglass board are the same as those of the insulating board, and the length and width dimensions of the upper metal plate are greater than those of the insulating board.

[0011] The thickness of the upper metal plate is less than the thickness of the fiberglass plate, and the thickness of the fiberglass plate is less than the thickness of the insulating plate.

[0012] Preferably, the connection between the first mounting hole, the second mounting hole and the hand-tightened metal self-test screw is a mating thread connection.

[0013] Preferably, it further includes a shielded signal line, the connection end of which is located between the insulating plate and the fiberglass plate, the connection end of which is connected to the upper metal plate, and the shielding layer of the shielded signal line is connected to the metal plating layer on the surface of the fiberglass plate.

[0014] A method for verifying the standard decay time of an ionization electrostatic detection device, using the aforementioned verification device for the standard decay time of an ionization electrostatic detection device, includes the following steps:

[0015] Step S1, routine testing steps: Install the hand-tightened metal self-test screw into the second mounting hole on the rear shell of the main unit of the device, disconnect the RC discharge loop, the detection loop impedance of the main unit of the device is greater than 1000GΩ, and the main unit of the device is used for electrostatic attenuation detection;

[0016] Step S2: Switch to self-verification step. Remove the hand-tightened metal self-test screw in the second mounting hole and screw it into the first mounting hole until the hand-tightened metal self-test screw and the metal nut make tight conductive contact, thus completing the standard RC discharge circuit and forming a complete closed discharge loop.

[0017] Step S3: Standard capacitor charging and energy storage step, charging the standard capacitor to 1000V;

[0018] Step S4, Measure the decay time: Cut off the high voltage charging output, and continuously discharge the electrostatic charge stored in the standard capacitor to the grounded metal plate through a standard resistor of 100GΩ±1%. Measure the decay time of the voltage from 1000V to 100V.

[0019] Step S5, the verification and comparison of measured and theoretical decay time: the theoretical reference decay time of the standard RC discharge circuit is calculated in advance based on the RC discharge theoretical formula, which is approximately 5.06572s. The measured decay time obtained in step S4 is compared with the theoretical reference decay time for self-verification.

[0020] Step S6: Restore to normal testing status. After completing the self-verification, remove the hand-tightened metal self-test screw from the first mounting hole and reassemble it into the second mounting hole. Disconnect the RC discharge circuit, and the main unit of the device returns to normal electrostatic testing conditions.

[0021] The beneficial effects of this invention are:

[0022] Firstly, the ionization electrostatic detection equipment has its own standard decay time verification. It has a built-in standard resistor of 100GΩ ±1% and a standard capacitor of 22pF±1% to form a standard RC discharge circuit. No external third-party standard instruments are required. The accuracy of the equipment decay time measurement can be verified on-site, which greatly reduces the cost of metrological verification and operation time.

[0023] Secondly, it features a built-in hand-tightened metal self-test screw for easy operation. The hand-tightened metal self-test screw is used to mechanically switch and verify the continuity of the circuit. Under normal testing conditions, it verifies that the RC discharge circuit is completely disconnected.

[0024] Third, the high-resistance flat panel assembly design has a total loop impedance greater than 1000GΩ, with no bypass leakage current, fully meeting the IEC and GB / T electrostatic detection impedance requirements and will not interfere with normal sample testing.

[0025] Fourth, the shielding layer and the grounding metal plate share the same ground, which effectively suppresses external electromagnetic interference, improves the stability of voltage acquisition signals, and ensures the reliability of standard verification data. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the RC discharge circuit in this embodiment;

[0027] Figure 2 This is an exploded view of the metal test plate, hand-tightened metal self-test screw, standard capacitor, standard resistor, plastic insulating pad, grounding metal plate, and shielded signal cable used in this embodiment.

[0028] Figure 3This is a perspective view of the metal test plate, hand-tightened metal self-test screw, standard capacitor, standard resistor, plastic insulating pad, grounded metal plate, and shielded signal cable used in this embodiment.

[0029] Figure 4 This is a perspective view of the ionization electrostatic detection device in this embodiment.

[0030] In the attached image:

[0031] 10. Main unit; 11. Second mounting hole; 20. Metal test plate; 21. Upper metal plate; 22. Insulating plate; 23. Fiberglass board; 24. Metal nut; 25. Through hole; 26. First mounting hole; 30. Hand-tightened metal self-test screw; 40. Standard capacitor; 50. Standard resistor; 60. Plastic insulating pad; 70. Grounding metal plate; 80. Shielded signal cable. Detailed Implementation

[0032] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0033] Example 1, see Figures 1-4 As shown, this embodiment discloses a standard decay time verification device for ionization electrostatic detection equipment. It can accurately verify the standard decay time of the detection equipment, featuring a built-in decay time verification structure for convenient, rapid, and accurate standard verification of the detection equipment. The device includes a main unit 10, a metal test plate 20, a hand-tightened metal self-test screw 30, and an RC discharge circuit. The metal test plate 20 is positioned on the top of the main unit 10. The RC discharge circuit includes a standard resistor 50 of 100 GΩ ± 1% and a standard capacitor 40 of 22 pF ± 1%, connected in series to form an RC... The discharge circuit, the metal test plate 20 includes an upper metal plate 21, an insulating plate 22, and a fiberglass plate 23 arranged from top to bottom. A metal nut 24 is embedded in the fiberglass plate 23. The end face of the fiberglass plate 23 facing the insulating plate 22 is plated with a metal layer. A plastic insulating pad 60 is provided below the metal test plate 20. A standard resistor 50 is installed at the bottom of the plastic insulating pad 60. The lower end of the metal nut 24 extends into the standard resistor 50 at the bottom of the plastic insulating pad 60 and is electrically connected to one end of the standard resistor 50. The upper metal plate 21 and the insulating plate 22 are provided with through holes 25 that correspond to the holes of the metal nut 24. The two through holes 25 and the metal nut 24 form a first mounting hole 26. A second mounting hole 11 is provided on the rear shell of the main unit 10. One of the first mounting hole 26 and the second mounting hole 11 can be installed by hand-tightening the metal self-test screw 30.

[0034] When the hand-tightened metal self-test screw 30 is screwed into the second mounting hole 11, the main unit 10 of the equipment is tested normally, the RC discharge loop is in the open state, and the detection loop impedance of the main unit 10 of the equipment is greater than 1000GΩ.

[0035] When the hand-tightened metal self-test screw 30 is screwed into the first mounting hole 26, the hand-tightened metal self-test screw 30 makes conductive contact with the metal nut 24. The main unit of the equipment 10 performs attenuation time verification. The standard resistor 50 and the standard capacitor 40 are connected, closing the RC discharge circuit. The standard capacitor 40 has an initial charging voltage of 1000V and discharges to 100V, obtaining the theoretical attenuation time t, thus realizing the self-verification of the equipment's attenuation detection accuracy.

[0036] The theoretical decay time t in this embodiment is 5.06572s.

[0037] The mathematical relationship between voltage, time, and RC can be derived from Kirchhoff's Current Law (KCL):

[0038] (1)

[0039] Based on the current-voltage characteristics of the component, we can obtain:

[0040] (2)

[0041] (3)

[0042] Substituting equations (2) and (3) into (1) and rearranging, we obtain the differential equation:

[0043] (4)

[0044] Solving this first-order linear differential equation in the time domain yields the general solution:

[0045] (5)

[0046] Wherein, time constant ;

[0047] U c =U0, is the capacitor voltage, U r It is the voltage across the resistor; R and C are the resistor and capacitor of a first-order parallel circuit.

[0048] R is the 100GΩ resistance to ground connected in parallel in the metal test plate 20, C refers to the equivalent capacitance of the metal parts, plastic parts, and connecting wires of the metal test plate 20 to ground, and U c (t) is a function of the capacitor voltage changing with time, i c (t), i R (t) is a function of the capacitor current and resistor current as a function of time. It is the derivative of the capacitor voltage function with respect to time, and e is the mathematical exponential constant. The purpose of solving the formula is to obtain formula (5), the relationship between voltage, RC and time t, and thus to find the time t.

[0049] Substituting the time constant into the device parameters for the standard decay time of the detection equipment, the standard decay process can be equivalent to a zero-input response. During electrostatic discharge (ESD) detection decay, the design voltage decays from 1000V to 100V, and the resistance... ±1%, Capacitor ±1%.

[0050] Substituting the above parameters into the formula yields:

[0051]

[0052] In summary, when the RC loop is closed at point S, the design attenuation standard time is approximately t ≈ 5.06572 s.

[0053] A grounding metal plate 70 is provided below the plastic insulating pad 60, and one end of the standard resistor 50 is connected to the grounding metal plate 70 below.

[0054] The length and width dimensions of the fiberglass board 23 are the same as those of the insulating board 22, while the length and width dimensions of the upper metal plate 21 are greater than those of the insulating board 22. The thickness of the upper metal plate 21 is less than the thickness of the fiberglass board 23, and the thickness of the fiberglass board 23 is less than the thickness of the insulating board 22. In this embodiment, the dimensions of the insulating board 22 are 140 mm * 140 mm * 7 mm, the dimensions of the upper metal plate 21 are 152.5 mm * 152.5 mm * 1.2 mm, and the dimensions of the fiberglass board 23 are 140 mm * 140 mm * 1.6 mm. The connections between the first mounting hole 26, the second mounting hole 11, and the hand-tightened metal self-test screw 30 are all made using mating threaded connections.

[0055] The standard decay time verification device for the ionization electrostatic detection equipment in this embodiment also includes a shielded signal line 80. The connection end of the shielded signal line 80 is located between the insulating plate 22 and the fiberglass plate 23. The connection end of the shielded signal line 80 is connected to the upper metal plate 21. The shielding layer of the shielded signal line 80 is connected to the metal plating layer on the surface of the fiberglass plate 23.

[0056] The working principle of this embodiment is as follows: when it is necessary to enter the standard decay time verification, such as Figure 4 As shown, unscrew the hand-tightened metal self-test screw 30 on the rear shell of the main unit 10, and then screw it into the first mounting hole 26 of the metal test plate 20 to achieve closed-loop connection between the internal resistance and the plate's capacitance, thereby reducing ±1000V to 100V. The time display is t≈5.06572s.

[0057] Example 2: A method for verifying the standard decay time of an ionization electrostatic detection device, using an ionization electrostatic detection device standard decay time verification apparatus, includes the following steps:

[0058] Step S1, routine testing steps: Install the hand-tightened metal self-test screw 30 into the second mounting hole 11 on the rear shell of the main unit 10 of the equipment, disconnect the RC discharge loop, and the detection loop impedance of the main unit 10 is greater than 1000GΩ (10 to the power of 12 ohms). The main unit 10 performs electrostatic attenuation testing.

[0059] Step S2: Switch to self-verification step. Remove the hand-tightened metal self-test screw 30 in the second mounting hole 11 and screw it into the first mounting hole 26 until the hand-tightened metal self-test screw 30 and the metal nut 24 make tight conductive contact, thus completing the standard RC discharge circuit and forming a complete closed discharge loop.

[0060] Step S3, standard capacitor 40 charging and energy storage step, charging the standard capacitor 40 to 1000V;

[0061] Step S4, measured decay time step: disconnect the high voltage charging output, and continuously discharge the electrostatic charge stored in the standard capacitor 40 to the grounded metal plate 70 through the standard resistor 50 of 100GΩ±1%. Measure the actual decay time of the voltage from 1000V to 100V.

[0062] Step S5, the verification and comparison of measured and theoretical decay time: the theoretical reference decay time of the standard RC discharge circuit is calculated in advance based on the RC discharge theoretical formula, which is approximately 5.06572s. The measured decay time obtained in step S4 is compared with the theoretical reference decay time for self-verification.

[0063] Step S6: Restore to normal testing status. After completing the self-verification, remove the hand-tightened metal self-test screw 30 from the first mounting hole 26 and reassemble it into the second mounting hole 11. Disconnect the RC discharge circuit and the main unit 10 of the equipment returns to normal electrostatic testing conditions.

[0064] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A standard decay time verification device for ionization electrostatic detection equipment, characterized in that: The device includes a main unit, a metal test plate (20), a hand-tightened metal self-test screw (30), and an RC discharge circuit. The metal test plate (20) is located on the top of the main unit. The RC discharge circuit includes a standard resistor (50) of 100 GΩ ± 1% and a standard capacitor (40) of 22 pF ± 1%, which are connected in series to form an RC circuit. The discharge circuit includes an upper metal plate (21), an insulating plate (22), and a fiberglass plate (23) arranged from top to bottom. A metal nut (24) is embedded in the fiberglass plate (23). A plastic insulating pad (60) is provided below the metal test plate (20). A standard resistor (50) is installed at the bottom of the plastic insulating pad (60). The lower end of the metal nut (24) extends into the standard resistor (50) at the bottom of the plastic insulating pad (60) and is electrically connected to one end of the standard resistor (50). The upper metal plate (21) and the insulating plate (22) are each provided with through holes (25) corresponding to the holes of the metal nut (24). The two through holes (25) and the metal nut (24) form a first mounting hole (26). A second mounting hole (11) is provided on the rear shell of the main unit of the equipment. One of the first mounting hole (26) and the second mounting hole (11) can be installed by hand-tightening the metal self-test screw (30). When the hand-tightened metal self-test screw (30) is screwed into the second mounting hole (11), the main unit of the equipment is tested normally, the RC discharge loop is in the open state, and the detection loop impedance of the main unit of the equipment is greater than 1000GΩ; When the hand-tightened metal self-test screw (30) is screwed into the first mounting hole (26), the hand-tightened metal self-test screw (30) and the metal nut (24) make conductive contact. The main unit of the device (10) performs attenuation time verification. The standard resistor (50) and the standard capacitor (40) are connected to close the RC discharge circuit. The standard capacitor (40) has an initial charging voltage of 1000V and discharges to 100V to obtain the theoretical attenuation time t, thereby realizing the self-verification of the device attenuation detection accuracy.

2. The standard decay time verification device for ionization electrostatic detection equipment according to claim 1, characterized in that: The theoretical decay time t is 5.06572s.

3. The standard decay time verification device for ionization electrostatic detection equipment according to claim 1, characterized in that: A grounding metal plate (70) is provided below the plastic insulating pad (60), and one end of the standard resistor (50) is connected to the grounding metal plate (70) below.

4. The standard decay time verification device for ionization electrostatic detection equipment according to claim 1, characterized in that: The end face of the fiberglass board (23) facing the insulating board (22) is plated with a metal layer.

5. The standard decay time verification device for ionization electrostatic detection equipment according to claim 1, characterized in that: The length and width of the fiberglass board (23) are the same as those of the insulating board (22), and the length and width of the upper metal plate (21) are greater than those of the insulating board (22). The thickness of the upper metal plate (21) is less than the thickness of the fiberglass plate (23), and the thickness of the fiberglass plate (23) is less than the thickness of the insulating plate (22).

6. The standard decay time verification device for ionization electrostatic detection equipment according to claim 1, characterized in that: The first mounting hole (26), the second mounting hole (11), and the hand-tightened metal self-test screw (30) are all connected by mating threads.

7. The standard decay time verification device for ionization electrostatic detection equipment according to claim 4, characterized in that: It also includes a shielded signal line (80), the connection end of which is located between the insulating plate (22) and the fiberglass plate (23), the connection end of which is connected to the upper metal plate (21), and the shielding layer of the shielded signal line (80) is connected to the metal plating layer on the surface of the fiberglass plate (23).

8. A method for verifying the standard decay time of an ionization electrostatic detection device, characterized in that: The standard decay time verification device for ionization electrostatic detection equipment according to any one of claims 1-7 includes the following steps: Step S1, routine testing steps: Install the hand-tightened metal self-test screw (30) in the second mounting hole (11) on the rear shell of the main unit of the device, disconnect the RC discharge loop, the detection loop impedance of the main unit of the device is greater than 1000GΩ, and the main unit of the device is used for electrostatic attenuation detection; Step S2: Switch to self-verification step, remove the hand-tightened metal self-test screw (30) in the second mounting hole (11), screw it into the first mounting hole (26) until the hand-tightened metal self-test screw (30) and the metal nut (24) make tight conductive contact, conduct the standard RC discharge circuit, and form a complete closed discharge loop. Step S3, standard capacitor (40) charging and energy storage step, charging the standard capacitor (40) to 1000V; Step S4, measured decay time step: cut off the high voltage charging output, and continuously discharge the electrostatic charge stored in the standard capacitor (40) to the grounded metal plate (70) through the standard resistor (50) of 100GΩ±1% and measure the actual decay time of the voltage from 1000V to 100V. Step S5, the verification and comparison of measured and theoretical decay time: the theoretical reference decay time of the standard RC discharge circuit is calculated in advance based on the RC discharge theoretical formula, which is approximately 5.06572s. The measured decay time obtained in step S4 is compared with the theoretical reference decay time for self-verification. Step S6: Restore to normal testing status. After completing the self-verification, remove the hand-tightened metal self-test screw (30) from the first mounting hole (26) and reassemble it into the second mounting hole (11). Disconnect the RC discharge circuit and the host device returns to normal electrostatic testing conditions.

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