Resistance sheet for preventing silver layer from short circuit

Abstract

The utility model provides a kind of resistance disc for preventing silver layer free short circuit, including substrate, the substrate is sequentially printed and is provided with first silver layer, second silver layer, third silver layer, the end of the free end of the one side of first silver layer and the end of the free end of the one side of third silver layer are printed and are provided with carbon film layer around the periphery of second silver layer, gap is formed between the second silver layer and the first silver layer and the third silver layer respectively, insulating paint coating corresponding with the second silver layer is coated in the gap;The one side edge of the insulating paint coating is covered on the outside edge of the second silver layer, and the other side edge of the insulating paint coating is covered on the inside edge of the first silver layer, third silver layer, carbon film layer respectively.Effectively prevent silver layer free, avoid short circuit, improve reliability under high temperature and high humidity load conditions.

Description

Technical Field

[0001] This utility model relates to the field of resistor sheet technology, specifically to a resistor sheet that prevents silver layer ionization and short circuit. Background Technology

[0002] Chinese Patent Publication No. CN209103884U, published on July 12, 2019, discloses a positioning resistor for a rocker potentiometer. The resistor includes a resistor with a circular through-hole in its center. The bottom of the resistor has a first mounting hole, a second mounting hole, and a third mounting hole sequentially arranged therefrom. A positioning hole is also provided above the first mounting hole. A first silver layer, a second silver layer, and a third silver layer are respectively provided on the outer sides of the first, second, and third mounting holes, all covering the surface of the resistor. A first sulfide layer is connected to the upper end of the first silver layer, a second sulfide layer is connected to the upper end of the second silver layer, and a third sulfide layer is connected to the upper end of the third silver layer. Both the first and third sulfide layers have an arc-shaped structure, and a carbon film layer is connected to their top ends. The second sulfide layer is circular and surrounds the outside of the circular through-hole, with gaps between the second sulfide layer and the first, carbon film, and third sulfide layers. The resistor element also has clearance grooves at both ends on its lower side. The technical problem with this prior art is: Figure 1 As shown, in a high-temperature and high-humidity environment under load, such as the temperature regulating valve of a water heater in a shower room, silver ions may ionize on the substrate 10, which may cause a short circuit hazard. Given this situation, it is urgent to improve the situation. Utility Model Content

[0003] To address the above problems, this utility model provides a resistor that effectively prevents silver layer ionization, avoids short circuits, and improves reliability under high temperature and high humidity load conditions.

[0004] To achieve the above objective, a resistor sheet for preventing silver layer ionization and short circuits is provided, comprising a substrate on which a first silver layer, a second silver layer, and a third silver layer are sequentially printed. A carbon film layer surrounding the second silver layer is printed between the free end of one side of the first silver layer and the free end of one side of the third silver layer. Gaps are formed between the second silver layer and the first and third silver layers, respectively. An insulating varnish coating with a shape corresponding to the second silver layer is coated at the gaps. One edge of the insulating varnish coating covers the outer edge of the second silver layer, and the other edge of the insulating varnish coating covers the inner edges of the first silver layer, the third silver layer, and the carbon film layer, respectively.

[0005] Preferably, the thickness of the insulating varnish coating is set to 10–30 μm.

[0006] The beneficial effects of this utility model are: by coating the gap with an insulating varnish coating whose shape corresponds to the second silver layer, one side edge of the insulating varnish coating covers the outer edge of the second silver layer, and the other side edge of the insulating varnish coating covers the inner edges of the first silver layer, the third silver layer, and the carbon film layer respectively, the silver layer is effectively prevented from detaching, short circuits are avoided, and the reliability under high temperature and high humidity load conditions is improved. Attached Figure Description

[0007] Figure 1 This is a schematic diagram of the silver ion ionization phenomenon in existing technologies.

[0008] Figure 2 This is a schematic diagram of the structure of this utility model.

[0009] Figure 3 This is a schematic diagram of the process steps of this utility model.

[0010] The reference numerals in the attached figures are: substrate 10, first silver layer 11, second silver layer 12, third silver layer 13, insulating varnish coating 14, and carbon film layer 15. Detailed Implementation

[0011] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the implementation of the present invention is not limited thereto.

[0012] Reference Figure 2-3 As shown: A resistor sheet for preventing silver layer ionization and short circuits includes a substrate 10. A first silver layer 11, a second silver layer 12, and a third silver layer 13 are sequentially printed on the substrate 10. A carbon film layer 15 surrounding the second silver layer 12 is printed between the free ends of the first silver layer 11 and the third silver layer 13. Gaps are formed between the second silver layer 12 and the first and third silver layers 11, respectively. An insulating varnish coating 14 with a shape corresponding to the second silver layer 12 is coated at the gaps. One edge of the insulating varnish coating 14 covers the outer edge of the second silver layer 12, and the other edge of the insulating varnish coating 14 covers the inner edges of the first silver layer 11, the third silver layer 13, and the carbon film layer 15, respectively. The thickness of the insulating varnish coating 14 is set to 10-30 μm. In this embodiment, the insulating varnish coating 14 fills the gaps and isolates air and moisture, effectively preventing silver layer ionization (such as silver ion migration or peeling) and avoiding short circuits. At the same time, its high insulation performance and uniform electric field distribution reduce the potential gradient, reduce the risk of partial discharge, and improve mechanical strength and heat dissipation capacity, thereby significantly enhancing reliability and chemical stability under high temperature and high humidity load conditions.

[0013] The above embodiments illustrate only one implementation of this utility model, and while the description is relatively specific and detailed, it should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A resistive sheet for preventing silver layer ionization and short circuit, comprising a substrate (10), wherein a first silver layer (11), a second silver layer (12), and a third silver layer (13) are sequentially printed on the substrate (10), wherein a carbon film layer (15) surrounding the second silver layer (12) is printed between the free end of the first silver layer (11) and the free end of the third silver layer (13), and gaps are formed between the second silver layer (12) and the first silver layer (11) and the third silver layer (13), characterized in that: An insulating varnish coating (14) with a shape corresponding to the second silver layer (12) is applied to the gap; one side edge of the insulating varnish coating (14) covers the outer edge of the second silver layer (12), and the other side edge of the insulating varnish coating (14) covers the inner edges of the first silver layer (11), the third silver layer (13), and the carbon film layer (15), respectively.

2. The resistive element for preventing silver layer ionization and short circuits according to claim 1, characterized in that, The thickness of the insulating varnish coating (14) is set to 10-30 μm.

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