CN103648261A

CN103648261A - Computer case shielding method

Info

Publication number: CN103648261A
Application number: CN201310699681.0A
Authority: CN
Inventors: 史亚婷
Original assignee: CETC 41 Institute
Current assignee: CETC 41 Institute
Priority date: 2013-12-18
Filing date: 2013-12-18
Publication date: 2014-03-19

Abstract

The invention provides a computer case shielding method. The method comprises the steps of step1, arranging salient points at equal intervals on the matching surfaces of shields respectively; step2, performing interference squeezing contact on the salient points and the shield matching surfaces to achieve low impedance connection of the two shields. According to the method, accessories are not needed to be added alone, assembly is facilitated, the cost is reduced, the structural design is flexible, the accessories are saved, and material costs are saved.

Description

A kind of shielding case method

Technical field

The invention belongs to shielding case technical field, in particular a kind of shielding case method.

Background technology

On the shielding case of any practicality, have gap, these gaps are because interim overlap joint between barricade causes.Due to the conduction discontinuity in gap, at place, gap, can produce electromagnetic leakage.For impermanency overlap joint, adopting the shielding materials such as electromagnetic shielding liner is the comparatively general effective method adopting at present.

Electromagnetic shielding liner is the material of a kind of good springiness, good conductivity.This material being filled in to place, gap, can keeping conduction continuity, is the good method that solves electromagnetic slot-leakage.

The hardness of liner needs suitably, and hardness is too low, easily causes loose contact, and screening effectiveness is low; Hardness is too high, needs larger pressure, to structural design, increases difficulty.Liner only has while there is under external force certain deformation, just has shielding action.After external force is removed, liner can not return to original shape completely, and permanent change has occurred.

Wire mesh pad can present larger induction reactance when high frequency, and screening effectiveness is reduced.

Conductive rubber is easily received moisture, mushroom, and the impact of weathering or heat, should be arranged on the inner side of environmental sealing

Beryllium copper reed D.C. resistance is low, and induction reactance is little, when low frequency and high frequency, all has compared with high shielding effect.But because complex-shaped, high to the installation requirement of structure, cause processing difficulties.

All electromagnetic shielding liners all exist cost high, the defect of being inconvenient to process.

Therefore, there is defect in prior art, needs to improve.

Summary of the invention

Technical problem to be solved by this invention is for the deficiencies in the prior art, and a kind of shielding case method is provided.

Technical scheme of the present invention is as follows:

A shielding case method, wherein, comprises the following steps:

Step 1: the uniformly-spaced salient point of spacing is set respectively on shield mating surface;

Step 2: salient point and shield mating surface are carried out to interference extrusion and contact, connect to realize the Low ESR of two shields.

Described screen method, wherein, in described step 1, described equally spaced being spaced apart is less than λ/20, the wavelength that wherein λ is required shielded signal.

Described screen method, wherein, in described step 1, the material of described salient point is shield itself, by special process, is processed to form.

Described screen method, wherein, in described step 1, described salient point is nonmetal, by conductive coating spray or take plating means to make it form conducting surface together with shield mating surface.

Described screen method, wherein, in described step 1, described salient point and described shield mating surface are wholely set.

Described screen method, wherein, realizes the method for interference extrusion contact for to fill by spiral shell, makes two salient points between shield adjacent screw realize extruding and coordinates; Or utilize the elasticity of material itself, by the fit system of T-shaped groove, realize the salient point extruding contact of T-shaped groove sidewall.

Adopt such scheme, not needing increases separately auxiliary, is easy to assembling, reduces costs, and structural design is flexible, and saves auxiliary, saves material cost.

Accompanying drawing explanation

Fig. 1 is the process schematic representation of the inventive method step 1.

Fig. 2 is the process schematic representation of the inventive method step 2.

Fig. 3 is the inventive method one embodiment schematic diagram.

Fig. 4 is another embodiment schematic diagram of the inventive method.

Embodiment

Below in conjunction with the drawings and specific embodiments, the present invention is described in detail.

Embodiment 1

As shown in Figure 3, at sheet metal component shielding case, surrounding overlap joint also fills in conjunction with spiral shell, forms closed cavity.

Step 1: at part 1(upper cover) on sidewall, stamp out the uniform projection in interval

While step 2: part 1(upper cover) with part 2(lower house) fastening, on part 1, inwall projection can closely cooperate with the outer wall of part 2.

In the present embodiment, when without projection, 12 of part is only that Low ESR connects in the place of screw link, because screw fastening can cause thin-wall shell distortion, and the gap that formation length is L.After part 1 upper punch projection, the place of projection also connects for Low ESR, and gap length shortens to L/3.Thereby improved the screening effectiveness of cabinet.

Embodiment 2

On the basis of above-described embodiment, as shown in Figure 4, be the injection moulding cabinet that part 1 and part 2 are assembled, inner-wall spraying electrically-conducting paint forms shielding case.

On part 1 end face, there is the continuous U-shaped groove of a circle; Part 2 end faces are the continuous T-shaped projection of a circle.After fastening, by the screw of four jiaos on large face, exert pressure, in the situation that not adding compliant conductive liner, between screw, forming spacing is the elongated bar gap of L.

Step 1: inject the half-cylindrical projection with matrix one in the U-lag both sides of upper cover piece 1.

Step 2: when upper and lower covers fastens, by the pressure 10 of surrounding screw, make upper cover form extruding at cylindrical projections place with lower cover and contact.

In the present embodiment, increase after projection, 12 projection cooperation place of part also connect for Low ESR, and gap length is reduced into L/6.Thereby improved the screening effectiveness of cabinet.

Embodiment 3

On the basis of above-described embodiment, further, as Figure 1-Figure 2, the invention provides a kind of shielding case method and comprise the following steps:

Step 1: as shown in Figure 1, the uniformly-spaced salient point 20 of spacing is set respectively on shield mating surface;

Step 2: as shown in Figure 2, salient point 20 is carried out to interference extrusion with shield mating surface 30 and contact, connect to realize the Low ESR of two shields.

In described step 1, described equally spaced being spaced apart is less than λ/20, the wavelength that wherein λ is required shielded signal.

In described step 1, the material of described salient point 20 is shield itself, by special process, is processed to form, and described special process is the existing attainable processing technology in this area.

In described step 1, described salient point 20 is nonmetal, by conductive coating spray or take plating means to make it form conducting surface together with shield mating surface.

Described screen method, wherein, in described step 1, as shown in Figure 1, described salient point 20 is wholely set with described shield mating surface.

In actual shielding, electromagnetic-field-shielded usefulness depends on the mechanism of cabinet to a great extent, i.e. the continuity of conduction.Seam on cabinet is the key reason that causes screen effect to decline.After fixing by screw between metal chassis upper and lower covers, because screw fastening can cause thin-wall shell distortion, form gap, electromagnetic wave can destroy through gap the screening effectiveness of cabinet.

If place adds all kinds of conductive gaskets in gap, liner can fill up gap, thereby effectively prevents the electromagnetic leakage in this type of gap.Yet in some specific occasion, the use of liner can make cost increase, assembling difficulty.

The simplest method is to increase a screw number, reduces the spacing of screw, can effectively reduce gap length, stops the leakage of high-frequency signal.Yet the increase of screw number, has increased assembly crewman's workload greatly.

For impermanency, connect, can in the situation that not increasing trip bolt, not use flexible conducting material, directly rely on shield itself, process the suitable projection in interval.By the mode of interference extrusion, thereby guarantee that seam crossing has abundant Low ESR tie point, realizes shielding action.

Should be understood that, for those of ordinary skills, can be improved according to the above description or convert, and all these improvement and conversion all should belong to the protection range of claims of the present invention.

Claims

1. a shielding case method, is characterized in that, comprises the following steps:

2. screen method as claimed in claim 1, is characterized in that, in described step 1, described equally spaced being spaced apart is less than λ/20, the wavelength that wherein λ is required shielded signal.

3. screen method as claimed in claim 1, is characterized in that, in described step 1, the material of described salient point is shield itself.

4. screen method as claimed in claim 1, is characterized in that, in described step 1, described salient point is nonmetal, by conductive coating spray or take plating means to make it form conducting surface together with shield mating surface.

5. screen method as claimed in claim 1, is characterized in that, in described step 1, described salient point and described shield mating surface are wholely set.

6. screen method as claimed in claim 1, is characterized in that, realizes the method for interference extrusion contact for to fill by spiral shell, makes two salient points between shield adjacent screw realize extruding and coordinates; Or utilize the elasticity of material itself, by the fit system of T-shaped groove, realize the salient point extruding contact of T-shaped groove sidewall.