A variable resistance sponge and its application

Abstract

The present invention relates to the technical field of eliminating static electricity from the human body, and in particular, to a varistor sponge and its application. The sponge comprises conductive particles of at least two diameters, d1 and d2, dispersed within a sponge matrix, where d2 is greater than d1. The conductive particles of diameter d1 provide the varistor sponge with a normal base resistivity R1, while the conductive particles of diameter d2 provide the varistor sponge with a compressed resistivity R2, where R1 is greater than R2. The beneficial effect of the sponge is that it generates no static sparks when used, and does not produce a shock sensation during the static electricity discharge process.

Description

Technical Field

[0001] The invention relates to the technical field of human body static discharge elimination, in particular to a variable resistance sponge and application thereof. Background Art

[0002] At present, human static electricity release balls are used to release human static electricity in flammable, explosive and anti-static places. Human static electricity release balls are also called human static electricity elimination balls. Static electricity elimination balls are a kind of human static electricity release product suitable for flammable, explosive and anti-static places. The main purpose of research and development is to safely discharge the static electricity charge accumulated by the human body in flammable, explosive hazardous areas and anti-static places, so as to avoid fire and explosion accidents caused by human static electricity, human electric shock and reduce the occurrence of static electricity damage to electronic components.

[0003] However, existing human body static discharge balls are made of stainless steel. The ball (touch ball) is connected to the ground. When the hand touches the ball, the static electricity of the human body is quickly introduced into the ground. During this process, the moment the hand touches the ball, a discharge spark may be generated. This spark is unsafe for flammable and explosive places. In addition, the human body will also feel an electric shock and feel uncomfortable.

[0004] Existing technologies include conductive rubber and conductive sponge products and production methods for applications such as rubber switches, contact rubber, pressure sensors, combustion wire core materials, and electromagnetic wave shielding and sealing materials. These applications require uniform or linearly varying resistivity. These materials are typically manufactured by combining a base material with a conductive material using rubber synthesis or sponge production processes. Conductive materials include metals, carbons, and conjugated polymers. Metallic conductive fillers include metals, metal / metal composites, and metal / non-metal composites. Carbon conductive fillers include conductive carbon black, nanographite, carbon fibers, carbon nanotubes, nickel-coated graphite conductive powder, graphene, and carbon black (30-40nm). Conjugated polymer conductive fillers include polyaniline, polypyrrole, and polyacetylene. Conductive particles are uniformly distributed within the base material, and particles with a size between 1 and 100nm are considered nanoconductive materials.

[0005] The variable resistance sponge in this case is specifically used in the field of static electricity elimination. It is required to maintain a certain high resistance (50 megohms to 1000 megohms) in its normal shape, and the resistance is required to decrease rapidly (0 megohms to 50 megohms) after compression. Summary of the Invention

[0006] Intrinsically safe electrical equipment is classified according to the GB3836.4-201 standard, which categorizes explosion-proof electrical appliances into flameproof, increased safety, and intrinsically safe types. Intrinsically safe electrical equipment is characterized by its entire circuit being intrinsically safe. This means that neither the sparks nor the thermal effects generated during normal operation or under specified fault conditions can ignite a specified explosive mixture. This means that these appliances rely not on explosion-proofing through their casing or fillings, but rather on ensuring that the energy of the sparks or thermal effects generated during normal operation or under specified fault conditions is less than 0.28mJ, equivalent to the minimum ignition energy at a gas concentration of 8.5% (the most explosive concentration).

[0007] The present invention aims to provide a variable resistance sponge material that can be attached to a grounded metal object and touched by hand to release static electricity from the human body without generating contact static sparks or an electric shock. The discharge of static electricity from the human body requires no sparks or electric shocks, and the discharge time must not be too long. Based on the equations Q (charge) = U (voltage) * C (capacitance) and I (current) = U (voltage) / R (resistance), the human body capacitance is usually constant. To avoid instantaneous discharge, a discharge resistor must be set, i.e., the discharge power must be limited to P = U. 2 / R (discharge power drops rapidly with the square of voltage), but when the resistance is constant, as the amount of electricity decreases, the voltage also decreases, the discharge current will decrease, and the discharge time will be extended. Since the discharge power P=U 2 / R (discharge power decreases rapidly with the square of voltage). If a discharge power is limited, the resistance must decrease rapidly for rapid discharge. Therefore, this solution maintains a certain high resistance (50 megohms to 1000 megohms) in the normal shape, and requires the resistance to decrease rapidly (0 megohms to 50 megohms) after compression, meeting the requirements of fast and safe static discharge.

[0008] According to the discharge time constant T=RC, under the condition of a certain C, the larger the resistance, the longer the discharge time required. If the resistance is too small, the discharge power will be large and sparks will be easily generated. Therefore, the problem to be solved in this case is variable resistance discharge.

[0009] Considering the concept of electrostatic grounding, materials with leakage resistance between 1 megohm and 1000 megohm are all considered anti-static materials. In fact, a resistance of several megohms is equivalent to direct grounding (zero resistance grounding is prone to generate electrostatic sparks).

[0010] The technical solution of the present invention is:

[0011] A varistor sponge is characterized in that at least two conductive particles of diameters d1 and d2 are dispersed in a sponge matrix, d2>d1, the conductive particles of diameter d1 provide the normal basic resistivity R1 of the varistor sponge, and the conductive particles of diameter d2 provide the compressed state resistivity R2 of the varistor sponge, R1>R2.

[0012] The variable resistance sponge is characterized in that the conductive particles with a diameter of d1 are continuously and evenly distributed in the sponge, and the conductive particles with a diameter of d2 are discretely and evenly distributed in the sponge.

[0013] The variable resistance sponge is characterized by: 1 nm≤d1≤1000nm, d2>100d1.

[0014] The variable resistance sponge is characterized by: 50×10 6 Ω.cm≤R1≤1000×10 6 Ω.cm, 1×10 6 Ω.cm≤R2≤200×10 6 Ω.cm.

[0015] The variable resistance sponge is characterized in that conductive particles with a diameter of d3 are dispersed in the sponge base material, and d1 < d3 < d2.

[0016] The variable resistance sponge is characterized in that the conductive particles are one of the following or a combination of the following: metal, metal / metal composite, metal / non-metal composite, carbon black, nanographite, carbon fiber, carbon nanotube, nickel-coated graphite conductive powder, graphene, carbon black, acetylene black, polyaniline, polypyrrole, and polyacetylene.

[0017] The variable resistance sponge is characterized in that the variable resistance sponge is arranged on the adhesive to form an instant sticker.

[0018] The application of the variable resistance sponge is characterized in that the variable resistance sponge is arranged on the fuel dispenser shell to release static electricity from the human body.

[0019] The application of the variable resistance sponge is characterized in that the variable resistance sponge is arranged on the nozzle tube of the fuel gun to release static electricity from the human body.

[0020] The application of the variable resistance sponge is characterized in that the variable resistance sponge is arranged on the handle of the fuel gun to release static electricity from the human body.

[0021] The application of the variable resistance sponge is characterized in that the variable resistance sponge is arranged on the door handle to release static electricity from the human body.

[0022] The application of the variable resistance sponge is characterized in that the variable resistance sponge is covered on gloves to release static electricity from the human body.

[0023] The production process of the variable resistance sponge for gloves is characterized by comprising the steps of:

[0024] ① Break the variable resistance sponge into pieces for later use;

[0025] ② Soak or coat the surface of the gloves made of conductive rubber with conductive glue;

[0026] ③ Evenly cover the surface of the gloves soaked or coated with conductive glue with the varistor sponge debris from step ①;

[0027] ④ After the conductive glue is solidified, the anti-static gloves are made.

[0028] The beneficial effects of the present invention are: no static electric spark is generated when the product is used, and no electric shock is generated to people during the process of static electricity release from the human body. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a normal structure diagram of the product of the present invention.

[0030] Figure 2 This is a structural diagram of the product of the present invention in a compressed state.

[0031] Figure 3 Schematic diagram of the resistance change over time of the present invention.

[0032] Figure 4 Schematic diagram of the discharge current changing with time according to the present invention.

[0033] Figure 5 It is the equivalent circuit diagram of the present invention.

[0034] Figure 6 The present invention is an embodiment of making an instant note from a self-adhesive sticker.

[0035] Figure 7 The present invention further provides an embodiment in which conductive particles of a third particle size are added.

[0036] Figure 8 This is an implementation scheme of the present invention applied to a gas station.

[0037] Figure 9 This is an embodiment of the present invention applied to a fuel gun.

[0038] Figure 10 The present invention is applied to a door handle.

[0039] Figure 11 This is an embodiment of the present invention applied to antistatic gloves. DETAILED DESCRIPTION

[0040] The present invention will be further described below with reference to the accompanying drawings and examples.

[0041] Figure 1The normal structure diagram of the product of the present invention is shown in FIG1000. 1000 is the product of the present invention. At least two conductive particles of different diameters are dispersed in the sponge matrix. 101 is a conductive particle of diameter d1, and 102 is a conductive particle of diameter d2. d2>d1. The conductive particle 101 of diameter d1 provides the normal basic resistivity R1 of the varistor sponge. The conductive particle 102 of diameter d2 provides the compressed state resistivity R2 of the varistor sponge. R1>R2, 1 nm≤d1≤1000nm, d2>100d1, 50×10 6 Ω.cm≤R1≤1000×10 6 Ω.cm, 1×10 6 Ω.cm≤R2≤200×10 6 Ω.cm.

[0042] As an implementation option: R1 is 200×10 6 Ω.cm, R2 is 100×10 6 Ω.cm, this solution can meet the optimal requirements for static electricity discharge in the human body, that is, the static electricity is released quickly without causing an electric shock to the human body.

[0043] The present invention is applied to eliminate static electricity from the human body. Currently, static discharge balls are used for this purpose. However, since these balls are made of metal, touching them with a finger can generate static sparks, posing a safety hazard in flammable and explosive environments and causing an electric shock. Currently, alternatives use touch balls made of sub-conductive materials (industry standard SY / T7354-2017, with a resistance of 10 megohms to 1000 megohms) to reduce the instantaneous static energy released from the human body and alleviate the electric shock. However, this requires a longer static discharge time, and due to the presence of resistance, it cannot completely discharge static electricity from the human body. The present invention's product can be attached to a grounded metal object, such as the metal casing of a gas station dispenser, and pressed by hand to completely discharge static electricity from the human body without sparks or electric shock.

[0044] Figure 2 This is a structural diagram of the product of the present invention in a compressed state. The conductive particles 102 with a diameter of d2 provide the compressed state resistivity R2 of the varistor sponge.

[0045] Figure 3 This is a schematic diagram of the resistance change over time of the present invention. The conductive particles with a diameter of d1 provide the normal basic resistance Rmax of the variable resistance sponge. By pressing the sponge product, the resistance will change with the compression amount, which can be converted into time T. Assuming that the ideal final compression resistance value is 0, a decreases linearly with time, b decreases slowly with time, and c decreases sharply with time. Since the discharge power P=U 2 / R (discharge power decreases rapidly with the square of voltage). If a discharge power is selected, the resistance must decrease rapidly for rapid discharge, so the b discharge curve is the best. The b discharge curve can be achieved by selecting the particle size of conductive particles with a diameter of d2. Through a large number of experiments, at least d2>100d1 is satisfied.

[0046] Figure 4 This is a schematic diagram of the discharge current changing with time in the present invention. In the ideal state, the original resistance is infinite, that is, the current is 0 at the beginning, and then reaches a safe maximum value Imax (the safe maximum value is the maximum current that does not generate sparks or electric shock). After a time T, the current is 0. In actual conditions, the current at the beginning is determined by the normal base resistivity R1 provided by the conductive particles with a diameter of d1 for Imin, and then reaches the maximum value Imax. After a time T, the current is 0.

[0047] Figure 5 This is the equivalent circuit diagram of the present invention. The conductive particles with a diameter of d1 provide the normal basic resistivity R1 of the varistor sponge, and the conductive particles with a diameter of d2 provide the compressed state resistivity R2 of the varistor sponge. Under normal conditions, the conductive particles with a diameter of d2 are in a discrete state, which is equivalent to R2 being opened by the switch K. When the sponge is squeezed, it is equivalent to the switch K being closed to connect R2 to the circuit, and the resistivity decreases rapidly.

[0048] Figure 6 This is an implementation scheme of the present invention in which a sticky note is made of self-adhesive adhesive. A sponge product is arranged on a self-adhesive conductive substrate 601. The conductive substrate can be made of conductive rubber. 603 is a substrate protrusion. The protrusion 603 exposes the conductive part of the conductive substrate 601 so that it can contact a grounded metal object. A pressure-sensitive self-adhesive adhesive 602 is coated on the substrate 601. Furthermore, conductive particles can be added to the components of the pressure-sensitive self-adhesive of the sticky note to produce a conductive pressure-sensitive self-adhesive adhesive. The pressure-sensitive self-adhesive adhesive is covered with protective paper 604. The protective paper is also called release paper, isolation paper, anti-sticking paper, and silicone oil paper. It is a kind of anti-sticking paper that prevents the prepreg from sticking and protects the prepreg from contamination.

[0049] Figure 7 In the embodiment of the present invention, conductive particles with a third particle size are added. Conductive particles with a diameter of d3 are also dispersed in the sponge matrix, where d1 < d3 < d2. This serves to adjust the discharge curve.

[0050] Figure 8 This is an embodiment of the present invention applied to a gas station. 801 is a gas pump, 803 is a fuel gun, and a sticky note 802 of the present invention is affixed to the metal casing of the gas pump to dissipate static electricity from the human body. Additionally, existing self-service gas pumps have a grounded metal keyboard 804. Static sparks can occur when a finger touches the keyboard. To address this, the keyboard can be covered with the present invention, which can also be made transparent.

[0051] Figure 9 In the embodiment of the present invention applied to a refueling gun, the product of the present invention is provided on the refueling gun 803 , and can be provided on the gun nozzle 902 or on the handle 901 .

[0052] Figure 10 This is an implementation scheme of the present invention applied to a door handle. Considering that people often get electrostatic shock when touching door handles in winter, the product 1002 of the present invention is provided on the door handle 1001 to prevent the human body from getting electrostatic shock. Door handles of course include car door handles.

[0053] Figure 11 In the embodiment of the present invention applied to antistatic gloves, the product of the present invention is set on the gloves. Of course, the product of the present invention can also be set on clothing.

[0054] The production process of the variable resistance sponge for gloves is characterized by comprising the steps of:

[0055] ① Break the variable resistance sponge into pieces for later use;

[0056] ② Soak or coat the surface of the gloves made of conductive rubber with conductive glue;

[0057] ③ Evenly cover the surface of the gloves soaked or coated with conductive glue with the varistor sponge debris from step ①;

[0058] ④ After the conductive glue is solidified, the anti-static gloves are made.

[0059] The product of the present invention can be pasted on all places where static electricity needs to be released, such as car doors, explosion-proof equipment, instruments, etc.

[0060] In addition, a glow discharge tube can be set in the electrostatic discharge circuit to display the static discharge process (if the explosion-proof requirements are met, such as using explosion-proof neon bubbles).

[0061] The above application modes and rules do not limit the basic characteristics of the methods and applications of the present invention, nor do they limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A variable resistance sponge, characterized in that: Conductive particles with a diameter of d1 and conductive particles with a diameter of d2 are dispersed in the sponge substrate, d2>d1, the conductive particles with a diameter of d1 provide the normal basic resistivity R1 of the varistor sponge, and the conductive particles with a diameter of d2 provide the compressed state resistivity R2 of the varistor sponge, R1>R2; Conductive particles with a diameter of d1 are continuously and evenly distributed in the sponge, while conductive particles with a diameter of d2 are discretely and evenly distributed in the sponge; 1 nm≤d1≤1000nm, d2>100d1, achieving a rapid decrease in resistance with compression; 50×10 6 Ω.cm≤R1≤200×10 6 Ohm.cm, 1×10 6 Ω.cm≤R2≤10×10 6 Ohm.cm; Conductive particles with a diameter of d3 are also dispersed in the sponge matrix, d1 < d3 < d2, to adjust the discharge curve.

2. The variable resistance sponge according to claim 1, characterized in that: The conductive particles are one of the following or a combination thereof: metal, metal / metal composite, metal / non-metal composite, carbon black, nanographite, carbon fiber, carbon nanotube, nickel-coated graphite conductive powder, graphene, carbon black, acetylene black, polyaniline, polypyrrole, and polyacetylene.

3. The variable resistance sponge according to claim 1, characterized in that: The variable resistance sponge is set on the adhesive to form a sticky note.

4. The application of the variable resistance sponge according to claim 1, characterized in that: The variable resistance sponge is set on the fuel dispenser shell to release static electricity from the human body.

5. The application of the variable resistance sponge according to claim 1, characterized in that: The variable resistance sponge is set on the nozzle tube of the fuel gun to release static electricity from the human body.

6. The application of the variable resistance sponge according to claim 1, characterized in that: The variable resistance sponge is set on the handle of the fuel gun to release static electricity from the human body.

7. The application of the variable resistance sponge according to claim 1, characterized in that: The variable resistance sponge is set on the door handle to release static electricity from the human body.

8. The application of the variable resistance sponge according to claim 1, characterized in that: The variable resistance sponge is covered on the gloves to release static electricity from the human body.

9. The production process of gloves using a variable resistance sponge according to claim 8, characterized in that it comprises the steps of: ① Break the variable resistance sponge into pieces for later use; ② Soak or coat the surface of the gloves made of conductive rubber with conductive glue; ③ Evenly cover the surface of the gloves soaked or coated with conductive glue with the varistor sponge debris from step ①; ④ After the conductive glue is solidified, the anti-static gloves are made.

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