阅读说明：本技术 一种安全释放静电的电路及方法及其应用 (Circuit and method for safely releasing static electricity and application thereof ) 是由 金宇轩 陆志仁 吴东辉 于 2020-04-24 设计创作，主要内容包括：本发明涉及静电释放消除的技术领域,特别是一种安全释放静电的电路及其应用。其特征是：包括电压检测单元、计算单元、压控变阻单元,压控变阻单元两端的电阻值由控制极G上的电压控制,压控变阻单元一端接地,另一端为静电释放端,当静电释放端触碰静电体,电压检测单元对静电体的电压进行检测,计算单元根据检测的电压按设定参数进行电阻值计算,所述电阻值由压控变阻单元实现,实现限定放电功率条件下快速安全释放静电体的静电,或实现限定放电电流条件下快速安全释放静电体的静电。有益效果是：在限定放电功率条件下快速安全释放静电体的静电实现本质安全型产品要求,或在限定放电电流条件下快速安全释放人体静电以避免静电对人体的电击。(The invention relates to the technical field of static electricity discharge elimination, in particular to a circuit for safely discharging static electricity and application thereof. The method is characterized in that: the voltage-controlled variable resistance unit is grounded at one end, the other end is an electrostatic discharge end, when the electrostatic discharge end touches the electrostatic body, the voltage detection unit detects the voltage of the electrostatic body, the calculation unit calculates the resistance value according to the detected voltage and set parameters, the resistance value is realized by the voltage-controlled variable resistance unit, and the static electricity of the electrostatic body is quickly and safely released under the condition of limiting discharge power or the static electricity of the electrostatic body is quickly and safely released under the condition of limiting discharge current. The beneficial effects are that: the static electricity of the static body is quickly and safely released under the condition of limited discharge power to meet the requirement of an intrinsically safe product, or the static electricity of the human body is quickly and safely released under the condition of limited discharge current to avoid the electric shock of the static electricity to the human body.)

1. A circuit for safely discharging static electricity is characterized in that: the voltage-controlled variable resistance unit is grounded at one end, the other end is an electrostatic discharge end, when the electrostatic discharge end touches the electrostatic body, the voltage detection unit detects the voltage of the electrostatic body, the calculation unit calculates the resistance value according to the detected voltage and set parameters, the resistance value is realized by the voltage-controlled variable resistance unit, and the static electricity of the electrostatic body is quickly and safely released under the condition of limiting discharge power or the static electricity of the electrostatic body is quickly and safely released under the condition of limiting discharge current.

2. A circuit for safely discharging static electricity is characterized in that: the static electricity discharge device is made of semiconductor materials and comprises a source electrode S, a grid electrode G, a drain electrode D, a source electrode S, a grid electrode G, a voltage detection unit and a calculation unit, when an electrostatic discharge end touches an electrostatic body, the voltage detection unit detects the voltage of the electrostatic body, the calculation unit calculates the resistance value according to the detected voltage and set parameters, the resistance value is realized by controlling the resistance between the drain electrode D and the source electrode S through the grid electrode G, and the static electricity of the electrostatic body is quickly and safely discharged under the condition of limited discharge power or the static electricity of the electrostatic body is quickly and safely discharged under the condition of limited discharge current.

3. A circuit for safely discharging static electricity is characterized in that: the static electricity discharge device comprises a field effect tube, a voltage detection unit and a calculation unit, wherein when an electrostatic discharge end touches an electrostatic body, the voltage detection unit detects the voltage of the electrostatic body, the calculation unit calculates a resistance value according to the detected voltage and set parameters, the resistance value is realized by controlling the resistance between a drain electrode D and a source electrode S through a grid electrode G of the field effect tube, and the static electricity of the electrostatic body is quickly and safely discharged under the condition of limited discharge power or the static electricity of the electrostatic body is quickly and safely discharged under the condition of limited discharge current.

4. A circuit for safely discharging static electricity according to claim 1, 2 or 3, wherein: the static body is a human body, the calculated resistance value is R = U/I, I < ═ 1mA, U is a real-time voltage of the human body, and I is a set current.

5. A circuit for safely discharging static electricity according to claim 1, 2 or 3, wherein: the electrostatic body is a production object, and the calculated resistance value is R = U²And P, P < 0.28mJ/s, U is the real-time voltage of the produced object, and P is the set discharge power.

6. A circuit for safely discharging static electricity according to claim 1, 2 or 3, wherein: and a resistor of 100 megohm to 1000 megohm is bridged between the D and the S.

7. Use of an electrostatic discharge circuit according to claim 1, 2 or 3, characterized in that: the static electricity releasing circuit is arranged on the oiling machine shell and used for releasing human static electricity; or the static electricity releasing circuit is arranged on the oil nozzle pipe of the oil gun and used for releasing the static electricity of the human body; or the static electricity releasing circuit is arranged on a handle of the oil gun and used for releasing the static electricity of the human body; or the static electricity releasing circuit is arranged on the door handle and used for releasing the static electricity of the human body; or the static electricity releasing circuit is arranged in the static electricity releasing ball circuit and used for releasing the static electricity of the human body; or an electrostatic discharge circuit is arranged in the electrostatic grounding clamp for discharging the static electricity of the production object.

8. A method for safely discharging a static electricity circuit, comprising the steps of:

setting the parameter I < ═ 1mA,

(1) detecting real-time human body voltage U;

(2) calculating resistance, wherein R = U/I, U is human body real-time voltage, and I is set current;

(3) the voltage-controlled variable resistance unit realizes a resistance value R;

(4) and (3) continuously executing the steps (1) to (3) in a period T.

9. A method for safely discharging a static electricity circuit, comprising the steps of:

setting the parameter P < 0.28mJ/s,

(1) detecting the real-time voltage U of the electrostatic body;

(2) calculating resistance value, R = U²P, U is the real-time voltage of the electrostatic body, and P is the set power;

(3) the voltage-controlled variable resistance unit realizes a resistance value R;

(4) and (3) continuously executing the steps (1) to (3) in a period T.

10. The method for safely discharging the circuit of static electricity according to claim 8 or 9, wherein: 0 seconds < T < ═ 5 seconds.

Technical Field

The invention relates to the technical field of static electricity discharge elimination, in particular to a circuit for safely discharging static electricity and application thereof.

Background

The static electricity comprises static electricity generated by human body movement and static electricity generated by moving materials and oil materials in the production process, for the human body static electricity, a human body static electricity releasing ball is used in inflammable, explosive and anti-static places to release the human body static electricity, the existing human body static electricity releasing ball is made of stainless steel, a ball body (a touch ball) is connected with the ground, the human body static electricity is rapidly introduced into the ground after a hand contacts the ball body, in the process, discharge sparks are possibly generated at the moment when the hand contacts the ball body, the sparks are unsafe for the inflammable and explosive places, and in addition, the human body can feel electric shock to generate discomfort. For static electricity generated in production, for example, when a fully loaded tank car unloads oil, the static electricity carried by the tank car (the tank car generally has a capacitance to ground of about 1500PF, and the static electricity generated by friction between wheels and the ground) is about 2-3KV, so that before oil unloading, an electrostatic grounding clamp must be used for connection to release the static electricity, and an electrostatic spark may be generated at the moment when the electrostatic grounding clamp engages with a conductor, and the electrostatic spark is enough to cause harm in an explosion area.

In order to avoid the sudden release of static electricity from an electrostatic body (a charged object or a human body), a resistor may be connected between the electrostatic body and a ground line, but the electrostatic voltage and capacitance of the electrostatic body are uncertain, so it is difficult to satisfy the requirement of safe discharge with a certain resistor.

Disclosure of Invention

The intrinsic safety is derived from the GB 3836.4-201 standard, explosion-proof electrical appliances are classified into explosion-proof type, safety-increasing type, intrinsic safety type and the like, and the intrinsic safety type electrical equipment is characterized in that all circuits are intrinsic safety circuits, namely, the circuits cannot ignite specified explosive mixtures due to electric sparks and thermal effects generated under normal work or specified fault states. That is, the electric appliance is not explosion-proof by the outer shell and the filler, but the energy of electric spark or heat effect generated by the circuit in normal use or failure is less than 0.28mJ, namely the gas concentration is 8.5% (the most explosive concentration) of the minimum ignition energy.

The invention aims to provide a circuit for safely releasing static electricity, which does not generate click feeling on human bodies according to the static electricity release requirement of the human bodies, meets the intrinsic safety requirement of GB 3836.4-201 standard on the static electricity release requirement of the static bodies in safety production, generates electric sparks or heat effect with energy less than 0.28mJ in normal use or fault, only gives an energy value but does not consider the energy release time, the actual process is that the energy released by the unit heat effect heats a substance Q = C M △ T of the unit mass, Q is the energy of the heat effect, M is the mass of the substance, C is the specific heat of the substance, △ T is the temperature change, and when the highest value of the temperature change reaches the ignition point of the substanceNamely explosion occurs, and heat dissipation is accompanied in the process (neglected here), so the index of the ignition substance is the energy released in unit time, and the invention introduces the concept of ignition power P, namely the instant energy release is not more than 0.28mJ, and the conversion is P =0.28 mJ/s. Through experimental tests, the current of the human body which does not generate electric shock feeling is not more than 1 mA. Two parameters are thus set: 1. the human body electrostatic discharge current I & lt-1 mA, and the over-current resistance R is R & lt U/I according to ohm's law; overcurrent resistance R = U in safety production²P, P < ═ 0.28mJ/s (derived from the GB 3836.4-201 standard, intrinsic safety requires a primary discharge energy of less than 0.28mJ, and the discharge time is less than 1 second, so P < ═ 0.28mJ/s is sufficient to cover the intrinsic requirement of a primary discharge energy of less than 0.28 mJ). Because the electrostatic voltage and the capacitance of the electrostatic body are uncertain, and the voltage of the electrostatic body is reduced along with the release of the electrostatic electricity (U = Q/C), the requirement of safe discharge is difficult to meet by using a certain resistor, so the safe discharge requirement at any moment is met by adopting the resistor which dynamically changes in real time, namely the real-time voltage of the electrostatic body is continuously tracked, the real-time resistance value meeting the safe discharge is calculated, and the requirement of quickly and safely releasing the static is realized.

The technical scheme of the invention is as follows:

a circuit for safely discharging static electricity is characterized in that: the voltage-controlled variable resistance unit is grounded at one end, the other end is an electrostatic discharge end, when the electrostatic discharge end touches the electrostatic body, the voltage detection unit detects the voltage of the electrostatic body, the calculation unit calculates the resistance value according to the detected voltage and set parameters, the resistance value is realized by the voltage-controlled variable resistance unit, and the static electricity of the electrostatic body is quickly and safely released under the condition of limiting discharge power or the static electricity of the electrostatic body is quickly and safely released under the condition of limiting discharge current.

A circuit for safely discharging static electricity is characterized in that: the static electricity discharge device is made of semiconductor materials and comprises a source electrode S, a grid electrode G, a drain electrode D, a source electrode S, a grid electrode G, a voltage detection unit and a calculation unit, when an electrostatic discharge end touches an electrostatic body, the voltage detection unit detects the voltage of the electrostatic body, the calculation unit calculates the resistance value according to the detected voltage and set parameters, the resistance value is realized by controlling the resistance between the drain electrode D and the source electrode S through the grid electrode G, and the static electricity of the electrostatic body is quickly and safely discharged under the condition of limited discharge power or the static electricity of the electrostatic body is quickly and safely discharged under the condition of limited discharge current.

A circuit for safely discharging static electricity is characterized in that: the static electricity discharge device comprises a field effect tube, a voltage detection unit and a calculation unit, wherein when an electrostatic discharge end touches an electrostatic body, the voltage detection unit detects the voltage of the electrostatic body, the calculation unit calculates a resistance value according to the detected voltage and set parameters, the resistance value is realized by controlling the resistance between a drain electrode D and a source electrode S through a grid electrode G of the field effect tube, and the static electricity of the electrostatic body is quickly and safely discharged under the condition of limited discharge power or the static electricity of the electrostatic body is quickly and safely discharged under the condition of limited discharge current.

The circuit for safely releasing static electricity is characterized in that: the static body is a human body, the calculated resistance value is R = U/I, I < ═ 1mA, U is a real-time voltage of the human body, and I is a set current.

The circuit for safely releasing static electricity is characterized in that: the electrostatic body is a production object, and the calculated resistance value is R = U²And P, P < 0.28mJ/s, U is the real-time voltage of the produced object, and P is the set discharge power.

The circuit for safely releasing static electricity is characterized in that: and a resistor of 100 megohm to 1000 megohm is bridged between the D and the S.

The application of the electrostatic discharge circuit is characterized in that: the static electricity releasing circuit is arranged on the housing of the oiling machine and used for releasing the static electricity of a human body.

The application of the electrostatic discharge circuit is characterized in that: the static electricity releasing circuit is arranged on a nozzle pipe of the oil gun and used for releasing human static electricity.

The application of the electrostatic discharge circuit is characterized in that: the static electricity releasing circuit is arranged on a handle of the oil gun and used for releasing static electricity of a human body.

The application of the electrostatic discharge circuit is characterized in that: the static electricity discharge circuit is arranged on the door handle and used for discharging the static electricity of the human body.

The application of the electrostatic discharge circuit is characterized in that: the static electricity discharge circuit is arranged in the static electricity discharge ball circuit and used for discharging the static electricity of the human body.

The application of the electrostatic discharge circuit is characterized in that: the electrostatic discharge circuit is arranged in the electrostatic grounding clamp and used for discharging static electricity of the production object.

A method for safely discharging a static electricity circuit, comprising the steps of:

the parameters I are set, and the parameters I,

(1) the voltage detection unit detects a real-time human body voltage U;

(2) the calculation unit calculates the resistance value, wherein R = U/I, U is the real-time voltage of the human body, and I is the set current;

(3) the voltage-controlled variable resistance unit realizes a resistance value R;

(4) and (3) continuously executing the steps (1) to (3) in a period T.

Further, the parameter I < ═ 1mA is set.

A method for safely discharging a static electricity circuit, comprising the steps of:

the parameter P is set, and the parameter P,

(1) the voltage detection unit detects the real-time voltage U of the electrostatic body;

(2) the calculating unit calculates the resistance value R = U²P, U is the real-time voltage of the electrostatic body, and P is the set power;

(3) the voltage-controlled variable resistance unit realizes a resistance value R;

(4) and (3) continuously executing the steps (1) to (3) in a period T.

Further, the parameter P < 0.28mJ/s is set.

The invention has the beneficial effects that: the static electricity of the static body is quickly and safely released under the condition of limited discharge power to meet the requirement of an intrinsically safe product, or the static electricity of the human body is quickly and safely released under the condition of limited discharge current to avoid the electric shock of the static electricity to the human body.

Drawings

Fig. 1 is a schematic diagram of the present invention.

Fig. 2 is a circuit diagram of the present invention using a field effect transistor.

FIG. 3 is a schematic diagram of the time variation of the ESD voltage according to the present invention.

FIG. 4 is a flow chart of the present invention.

Fig. 5 shows an embodiment of the present invention applied to an electrostatic grounding clamp.

Fig. 6 shows an embodiment of the invention applied to a gasoline station.

Fig. 7 is an embodiment of the present invention applied to a fuel nozzle.

Fig. 8 shows an embodiment of the present invention applied to a door handle.

Fig. 9 is an embodiment of the present invention applied to an electrostatic discharge ball.

Detailed Description

The invention is further illustrated with reference to the following figures and examples.

Fig. 1 is a schematic diagram of the present invention, a circuit 1000 includes a voltage-controlled varistor device 101, a voltage detection unit 103, and a calculation unit 104, wherein a resistance at two ends of the voltage-controlled varistor device 101 is controlled by a voltage on a control electrode G, one end of the voltage-controlled varistor device is grounded, the other end is an electrostatic discharge end 102, when an electrostatic body (an object or a person with static electricity) touches the electrostatic discharge end 102, the voltage detection unit continuously detects a charged voltage U of the electrostatic body with a period T, the calculation unit 104 calculates a resistance value R of the voltage-controlled varistor device 101 according to the real-time voltage U, the resistance value R is determined by a set parameter, when the electrostatic body is a human body, to avoid an electric shock of the electrostatic current to the human body, the resistance value is R = U/I, I < 1mA, U is a real-time voltage of the human body, I is a set current, when the electrostatic body is a production object, resistance value of R = U²And P, P & lt0.28 mJ/s, U is the real-time voltage of the produced object, P is the set power, and the electrostatic body voltage is discharged through the voltage-controlled variable resistance device 101, so that the electrostatic body static electricity is quickly and safely released under the condition of limited discharge current or the electrostatic body static electricity is quickly and safely released under the condition of limited discharge power. The implementation mode of the invention can be chip-level implementation or device implementation, and the chipThe stage implementation is to directly use the semiconductor technology to manufacture the voltage-controlled variable resistance module or the voltage-controlled variable resistance chip.

Fig. 2 is a circuit diagram of the field effect transistor according to the present invention, which includes a field effect transistor, a voltage detection unit 103, and a calculation unit 104, where the voltage detection unit 103 continuously detects a charged voltage U of an electrostatic body with a period T, the calculation unit 104 calculates a resistance value R of the field effect transistor according to the real-time voltage U, the resistance value R is determined by a set parameter, when the electrostatic body is a human body, to avoid an electric shock to the human body by an electrostatic current, the resistance value is R = U/I, I < ═ 1mA, U is a real-time voltage of the human body, I is a set current, when the electrostatic body is a production object, to avoid an explosion of a combustible gas caused by the electrostatic energy, and the resistance value is R = U²And P, P & ltequal to 0.28mJ/s, U is the real-time voltage of the produced object, P is the set power, and the static body electricity discharges through the field effect tube, so that the static body static electricity is quickly and safely released under the condition of limited discharge current or the static body static electricity is quickly and safely released under the condition of limited discharge power. The figure is an N-MOS tube, the same principle can be deduced to a P-MOS tube, when a source metal and a substrate of the field effect tube are connected together, a source electrode and a drain electrode can be used interchangeably, the characteristic change is small, the source electrode and the drain electrode of the field effect tube are symmetrical in structure and can be used interchangeably, and the grid-source voltage of a depletion type MOS tube can be positive or negative.

Fig. 3 is a schematic diagram of the time variation of the discharge voltage of the electrostatic body according to the present invention, wherein the discharge of the electrostatic body conforms to the RC discharge curve, and if the resistance is not changed, the curve conforms to a, i.e., the initial current is large, the voltage is rapidly decreased, and the later stage is stable discharge for a long time. If the variable resistor discharge of the invention is adopted, the curve conforms to b, and if the resistor in the first period is R1, the voltage in the second period detected by the voltage detection unit is smaller than the voltage in the first period, so the resistor R2 in the second period is smaller than R1, the electrostatic body voltage is rapidly reduced after a plurality of periods, and the electrostatic body voltage is ideally rapidly reduced to zero. For example, the capacitance of the human body is generally 200pF, and it is assumed that the static electricity of the human body is 10000V, in order to avoid the static electricity from shocking the human body, I is 1mA, R = U/I =10000V/1mA =10 mega ohm, according to the RC discharge curve, it takes more than 8 seconds (residual voltage) to completely discharge the voltage of the human body, and if the variable resistor of the present invention is used to discharge the static electricity of the human body for 2 seconds, the static electricity of the human body can be completely discharged.

Fig. 4 is a flow chart of the present invention, which includes the following steps for meeting the requirement of no-shock induction discharge of human body:

setting the parameter I < ═ 1mA,

(1) the voltage detection unit detects a real-time human body voltage U;

(2) the calculation unit calculates the resistance value, wherein R = U/I, U is the real-time voltage of the human body, and I is the set current;

(3) the voltage-controlled variable resistance unit realizes a resistance value R;

(4) and (3) continuously executing the steps (1) to (3) in a period T.

The discharge requirement of explosion-proof safety production comprises the following steps:

setting the parameter P < 0.28mJ/s,

(1) the voltage detection unit detects the real-time voltage U of the electrostatic body;

(2) the calculating unit calculates the resistance value R = U²P, U is the real-time voltage of the electrostatic body, and P is the set power;

(3) the voltage-controlled variable resistance unit realizes a resistance value R;

(4) and (3) continuously executing the steps (1) to (3) in a period T.

Selection of period T: the smaller the period T, the closer to the ideal value of electrostatic discharge, the smaller the period T, the more consumed the calculation resources of the calculation unit, and the higher the specification requirements on the circuit device. For an electrostatic body with a large capacitance, since the amount of static electricity carried is large, a long period T can be used, and 0 second < T < 5 seconds can be used. Of course, the period cannot limit the technical features of the present application.

Fig. 5 is an embodiment of the present invention applied to an electrostatic grounding clamp, and an application case for production safety is an electrostatic grounding clamp, in which both sides must be electrically connected to ground before loading and unloading oil from an oil truck and an oil depot, the conventional grounding clamp has a potential safety hazard, and since an electric spark may be generated when the grounding clamp engages a conductor, and the grounding clamp is unsafe in an explosion-proof area, an application of the present invention is to connect the circuit 1000 of the present invention in series between the oil truck and the oil depot through the electrostatic grounding clamp, when the electrostatic grounding clamp engages the oil truck, the circuit 1000 of the present invention detects an electrostatic voltage of the oil truck, calculates a safe overcurrent resistance of the electrostatic to perform electrostatic discharge after obtaining an electrostatic voltage value, and dynamically and continuously implement rapid and safe electrostatic discharge.

Fig. 6 shows an embodiment of the present invention applied to a gas station, 801 is a fuel dispenser, 803 is a fuel gun, and the device 802 of the present invention is disposed on a metal casing of the fuel dispenser for discharging static electricity from a human body. In addition, the existing self-service fuel dispenser is provided with a metal keyboard 804 and is grounded, electrostatic sparks can occur when fingers contact the keyboard, so that the keyboard can be provided with the device, and the product can be made into a chip or an embedded circuit.

Fig. 7 shows an embodiment of the present invention applied to a fuel nozzle, and the circuit or chip 1000 of the present invention is disposed on the fuel nozzle 803, and may be disposed on the nozzle 902 or the handle 901.

Fig. 8 shows an embodiment of the present invention applied to a door handle, and considering that a human hand touches the door handle in winter and is often electrostatically shocked, the door handle 1001 is provided with the circuit 1000 of the present invention to prevent a human body from being electrostatically shocked, and the door handle includes a door handle of an automobile.

Fig. 9 shows an embodiment of the present invention applied to an electrostatic discharge ball, 2000 is a touch ball of the electrostatic discharge ball, and an electrostatic discharge end 102 of the circuit 1000 of the present invention is connected to the touch ball, and human static electricity is discharged by touching with a human hand.

At present, the static electricity elimination of a human body adopts a static electricity releasing ball, and because the static electricity releasing ball is made of metal, when a finger touches the static electricity releasing ball, static electricity sparks can be generated, all potential safety hazards in an inflammable and explosive field can be caused, and meanwhile, the static electricity releasing ball can also generate electric shock feeling to the human body; at present, a sub-conductor touch ball body (the industry standard SY/T7354-2017, 10-1000 megohm resistance) is adopted, so that the instantaneous human body static electricity release energy is reduced, the electric shock feeling is reduced, but the human body static electricity release time needs to be prolonged, and the static electricity carried by the human body cannot be completely released due to the resistance, so that the circuit can completely release the human body static electricity without static spark and electric shock feeling.

The circuit can be arranged in all places needing to discharge static electricity, such as vehicle doors, explosion-proof equipment, instruments and the like.

In addition, a glow discharge tube can be arranged in the electrostatic discharge loop to display the discharge process of the static electricity (in the case of meeting the explosion-proof requirement, such as explosion-proof neon bubbles).

The above application modes and rules do not limit the basic features of the method and application of the present invention, and do not limit the scope of the present invention, and any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the scope of the present invention.