Resistor track for speed regulating switch of electric tool

Abstract

The utility model provides a resistance track for a speed control switch of an electric tool, which comprises an insulating substrate, the insulating substrate is divided into a conductive area A, a conductive area B, a signal on-off output area and a carbon film area, and the carbon film area is printed with a carbon film layer; the conductive area A and the conductive area B are respectively connected with the carbon film area, copper foil layers are respectively printed on the conductive area A, the conductive area B and the signal on-off output area, an electrogilding layer is formed on the upper surface of each copper foil layer, a sand blasting layer is arranged on the upper surface of each electrogilding layer, and the particle size of each sand blasting layer is set to be 500 meshes. And current noise in a high-frequency circuit can be effectively suppressed.

Description

TECHNICAL FIELD

[0001] The utility model relates to resistance track technical field, concretely relates to a resistance track for electric tool speed regulating switch. BACKGROUND

[0002] The resistance sheet is a kind of electronic component, usually be used in circuit adjustment current, reduce noise, divide voltage etc. Function. In industry, automobile, communication, electronic product etc. Field is widely applied. General electric tool, brush slides on copper foil and carbon film track, carries out the variation output of current voltage, copper foil surface treatment is generally electroplated gold or gold deposition process, in signal output process, often with " sizzle sizzle sizzle " current noise, this noise can not be obvious for the influence of high-power equipment, but, in high-end high-frequency electric tool is difficult to accept, for example in medical field. In view of this situation, it is urgent to improve. SUMMARY

[0003] To the above problems, the utility model provides a resistance track for electric tool speed regulating switch, can effectively inhibit the current noise in high-frequency circuit.

[0004] To achieve the above object, provide a kind of resistance track for electric tool speed regulating switch, including insulating substrate, the insulating substrate is divided and is formed with conductive area A, conductive area B, signal on-off output area and carbon film area, the carbon film area is printed with carbon film layer;The conductive area A and the conductive area B are connected with the carbon film area respectively, the conductive area A, conductive area B, signal on-off output area are all printed with copper foil layer, the upper surface of the copper foil layer is formed with electroplated gold layer, the upper surface of each electroplated gold layer is provided with sandblasting layer, the particle size of sandblasting layer is set as 500 mesh.

[0005] Preferably, the thickness of the electroplated gold layer is set to 1-5u.

[0006] Preferably, the sandblasting layer is set as quartz stone sandblasting layer.

[0007] Preferably, the upper surface of the carbon film area is covered with a protective layer.

[0008] Preferably, the copper foil layer thickness of the conductive area A, conductive area B, signal on-off output area is set to 35±15um, surface roughness Ra≤3.5um, RZ≤3.5um.

[0009] Preferably, the resistance of the carbon film layer is set to 1KΩ-3000 KΩ, the surface roughness of the carbon film layer is Ra≤1.5um.

[0010] The beneficial effects of this utility model are as follows: an electroplated gold layer is formed on the upper surface of the copper foil layer, and a sandblasting layer is provided on the upper surface of each electroplated gold layer. Fine sandblasting can adjust the microstructure of the surface of the electroplated gold layer, making the impedance of conductive area A, conductive area B, and signal switching output area more uniform, reducing signal reflection and electromagnetic interference. This has a good effect on suppressing current noise in high-frequency circuits. In addition, the sandblasting layer refines the surface microstructure, making the electroplated gold layer more uniform and flat, reducing unevenness between contact surfaces. The physical treatment reduces contact resistance, thereby reducing the arc and thermal noise caused by resistance fluctuations when current passes through. Attached Figure Description

[0011] Fig. 1 This is a front view of the present invention.

[0012] Fig. 2 This is a rear view of the present invention.

[0013] The attached figures are labeled as follows: insulating substrate 10, conductive area A11, conductive area B13, signal on / off output area 12, carbon film area 14, electroplated gold layer 15, sandblasted layer 16, and copper foil layer 17. Detailed Implementation

[0014] 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.

[0015] Reference Figs. 1-2 The diagram shows a resistor track for a speed control switch of a power tool, comprising an insulating substrate 10. The insulating substrate 10 is divided into a conductive region A11, a conductive region B13, a signal on / off output region 12, and a carbon film region 14. A carbon film layer is printed on the carbon film region 14. Conductive regions A11 and B13 are respectively connected to the carbon film region 14. Copper foil layers 17 are printed on each of the conductive regions A11, B13, and the signal on / off output region 12. An electroplated gold layer 15 is formed on the upper surface of the copper foil layer 17, and a sandblasting layer 16 is formed on the upper surface of each electroplated gold layer 15. In actual production, the copper foil layer 17 is immersed in a solution containing gold salts and electrified, allowing gold ions in the solution to be adsorbed onto the copper surface to form the electroplated gold layer 15. A sandblasting process is then used to spray quartz onto the surface of the electroplated gold layer 15 to form the sandblasting layer 16.

[0016] Preferably, the thickness of the electroplated gold layer 15 is set to 1–5 μm. The sandblasting layer 16 is a quartz sandblasting layer. The particle size of the sandblasting layer 16 is set to 500 mesh. The upper surface of the carbon film region 14 is covered with a protective layer. The copper foil layer thickness of the conductive region A11, conductive region B13, and signal on / off output region 12 is set to 35 ± 15 μm, with a surface roughness Ra ≤ 3.5 μm and Rz ≤ 3.5 μm. The resistance of the carbon film layer is set to 1 KΩ–3000 KΩ, with a surface roughness Ra ≤ 1.5 μm.

[0017] In this embodiment, fine sandblasting can adjust the microstructure of the electroplated gold layer surface, making the impedance of conductive area A, conductive area B, and signal switching output area more uniform, reducing signal reflection and electromagnetic interference. This has a good effect on suppressing current noise in high-frequency circuits. In addition, by setting a sandblasting layer, the sandblasting treatment refines the surface microstructure, making the electroplated gold layer more uniform and flat, reducing unevenness between contact surfaces, and the physical treatment reduces contact resistance, thereby reducing the arc and thermal noise caused by resistance fluctuations when current passes through.

[0018] 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 resistance rail for a speed control switch of a power tool, characterized in that: The system includes an insulating substrate (10), on which conductive regions A (11), conductive regions B (13), signal on / off output regions (12), and carbon film regions (14) are formed. Carbon film layers are printed on the carbon film regions (14). Conductive regions A (11) and B (13) are respectively connected to the carbon film regions (14). Copper foil layers (17) are printed on conductive regions A (11), B (13), and signal on / off output regions (12). Electroplated gold layers (15) are formed on the upper surface of the copper foil layers (17). Sandblasting layers (16) are provided on the upper surface of each electroplated gold layer (15). The particle size of the sandblasting layers (16) is set to 500 mesh.

2. The resistance rail for a speed control switch of a power tool according to claim 1, characterized in that, The thickness of the electroplated gold layer (15) is set to 1 to 5 μm.

3. The resistance rail for a speed control switch of a power tool according to claim 1, characterized in that, The sandblasting layer (16) is set as a quartz sandblasting layer.

4. A resistance rail for a speed control switch of a power tool according to claim 1, characterized in that, The upper surface of the carbon film region (14) is covered with a protective layer.

5. A resistance rail for a speed control switch of a power tool according to claim 1, characterized in that, The copper foil layer thickness of the conductive area A (11), conductive area B (13), and signal on / off output area (12) is set to 35±15um, and the surface roughness Ra≤3.5um, RZ≤3.5um.

6. A resistance rail for a speed control switch of a power tool according to claim 1, characterized in that, The resistance of the carbon film is set to 1KΩ~3000 KΩ, and the surface roughness Ra of the carbon film is ≤1.5um.

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