CN201134589Y - Connecting structure of RF coaxial connector with low intermodulation - Google Patents

Abstract

The utility model discloses a connecting structure of a low inter-modulation radio frequency coaxial connector which has smart design, and can effectively reduce the three-order inter-modulation, which comprises a joint casing, an inner conductor and an insulator, wherein one end of the joint casing is a joint with external threads, and the other end of the joint casing is a flange. And the different point from an original product lies in that a plane design is a buckled face after the flange. The utility model has the advantages that the back plane of the flange is improved into the buckled face, and the structural design gap of the buckled face is controlled within 0.05mm+-0.02mm, thereby improving the contact nonlinear greatly. A spline groove is arranged on the inner diameter bottom of the joint casing to increase the firmness of the inner conductor. The flange width of the joint casing flange end is designed in 3-10mm to prevent the possibility that screws can be symmetrically and evenly screwed up when laypeople install the screws. The connecting structure can be extensively applied in the radio frequency coaxial connectors of communication equipment and the mobile communication equipment, radio frequency coaxial cables and cable assembly.

Description

A kind of syndeton of low-intermodulation rf coaxial connector

Technical field

The utility model relates to the parts of mobile communication product, and the syndeton that relates in particular to a kind of low-intermodulation rf coaxial connector is improved.

Background technology

Along with the telecommunications especially fast development of mobile communication cause, radio frequency (RF) coaxial connector, radio frequency coaxial-cable and cable assembly thereof have obtained extensive use, network of widening in the world in recent years scope and Digital Cellular System and PCS Personal Communications System are in order to improve transmitted power level, reduce the noise critical value of receiver, promptly for the sensitivity that improves receiver or compression frequency bandwidth to realize the maximum communication ability of existed system, repartitioning of simultaneously intensive passage and frequency band proposed new requirement to passive device.One of them: reducing passive intermodulation distortion (PIM) then is more and more important problem of the communications industry.Passive intermodulation distortion (PIM) to the passive device generation, communication enterprise has generally proposed the requirement of third order intermodulation index clearly to radio frequency (RF) coaxial connector, radio frequency coaxial-cable and the assembly of using thereof both at home and abroad, thereby third order intermodulation index problem has just become radio frequency (RF) coaxial connector, radio frequency coaxial-cable and assembly manufacturer thereof and the common major issue of paying close attention to of communication enterprise.

Three PIM3 are that level is the strongest in the odd intermodulation product, inferiorly weaken successively for 5 times 7 times and 9, and in most of the cases, three intermodulation products are to form the most abominable factor of disturbing.Therefore the situation of third order intermodulation index must be improved and improve.

The utility model content

The present invention is directed to the technical problem of above-mentioned existence, proposed a kind of design ingenious, effectively reduce the syndeton of the low-intermodulation rf coaxial connector of third order intermodulation.

After deliberation, analyze and to draw: passive device non-linear (main pattern is: contact nonlinear and ferromagnetic non-linear) and skin effect and skin depth all are the primary conditions that produce PIM, therefore we again to connector construction, connector material, part processing precision and assembling, electroplating surface, test that each link may produce nonlinear factor and condition has been carried out investigation and drawn PRELIMINARY RESULTS: outer conductor is still selected basis brass HPb59-1 for use, electrodeposited coating is Cu bottoming 〉=0.5 μ m, CuSnZn alloy 〉=2 μ m; Inner wire is still selected common tin bronze QSn6.5-0.1 for use, and electrodeposited coating is; Cu 〉=0.5 μ m that feels secure, Ag 〉=2 μ m; Part processing and assembling, processes such as test are constant.Emphasis respectively contacts link to connector and redesigns.

The technical solution of the utility model is achieved in that a kind of syndeton of low-intermodulation rf coaxial connector, comprises joint shell, inner wire, insulator, and wherein an end of joint shell is for being with externally threaded interface, and the other end of joint shell is a flange.Its special feature is to be designed to male and fomale(M﹠F) at the flange back plane, to weaken the contact nonlinear of rear end face and equipment interface face.

Also the joint shell bottom is provided with spline simultaneously; To strengthen the stationarity of inner wire.

Above architecture advances design focal point is for flange end mounting interface structure, and the foundation of its basic technical theory is:

1. former design no concave-convex face, contact nonlinear degenerates.The contact force feature of no concave-convex face as shown in Figure 1, connector flanged plate 4 and wireless device mounting panel 5 be for large tracts of land contacts, aperture pretightning force deficiency; Nonlinear contact face and equivalent electric circuit are as shown in Figure 2.

(1) when two conductor contacts,,, always irregular and rough on microcosmic owing to surface roughness differs at the conductor contact surface.In general, following several contact condition is arranged: a) Metal Contact; B) accompany metal oxide film between the contact-making surface; C) accompany dielectric between the contact-making surface; D) small air gap; E) big air gap.

(2) the Metal Contact position a) and metal oxide film contact site b) form the main thoroughfare of electric current, contraction resistance that causes and rete resistance constitute the contact resistance of conductor.

(3) metal oxide (metal junction) b) oxide may be the unimolecule structure, and these rely on tunnel effect and the metal bridge that penetrates oxide-film to conduct electricity, thereby belongs to semimetal or semiconductor contact conduction;

(4) between contact-making surface, accompany the c of megohmite insulant place) then non-conductive, electric current is then around passing through to the Metal Contact place;

(5) at the big air gap e of place) electric current conducts electricity around the gap equally.

(6) at this c), e) under these two kinds of situations, electric current meets with impedance Z, itself is to produce a gap voltage V, gap voltage V is potential, may activate any one semiconductor and causes the arcing of tunnel effect and microcosmic.Compositions such as the capacitor C of faying face, inductance L and resistance R constitute electronic circuit, and its circuit model such as grade as shown in Figure 2.Wherein the V-I characteristic is non-linear.At the d of minim gap place) because the fluctuation of electric current or when strong signal is arranged is easy to form the arcing of microcosmic, the form that these unsettled arcings cause PIM to produce has had certainty, and the amplitude time to time change.To occurring in uncertain contact nonlinear, can represent with Fig. 3 near these voltage regime.

2. improve and be designed to male and fomale(M﹠F), contact nonlinear is greatly improved.The contact mechanics feature that male and fomale(M﹠F) arranged as shown in Figure 4, connector flanged plate 4 and wireless device mounting panel 5 are for small size contacts, the aperture pretightning force strengthens.

(1) leaves the gap around the screw, to guarantee outer conductor hole contact pressure on every side, because electric current is to flow with skin effect and certain skin depth;

(2) contact area reduces, and has also reduced the probability that occurs nonlinear every factor in the contact-making surface simultaneously, so that contact approaches to the linearity contact; But can guarantee that device inner wire and joint shell have enough water conservancy diversion areas.

3. the quality of contact surface state has determined the quality of contact nonlinear.Be mainly reflected in:

(1) contact pressure is big more, and Metal Contact is many more, and promptly small air gap or big air gap are few more; Because the contact of bigger front is arranged, dielectric that accompanies between the contact-making surface and metal oxide film trend towards the situation that might quilt be stabbed out, and make the many more of non-linear reduction, otherwise, non-linear serious more; Because bigger positive surface contact pressure is arranged, when signal strengthens, accompany metal oxide film between the contact-making surface, breakdown trend is also arranged, cause intermetallic welding, this itself also makes non-linear decline.

(2) not enough or because vibration when causing contact surface to form the separation of microcosmic, will produce severe nonlinear, the professional person is called this contact nonlinear " bolt effect (rasty bolt effect) " usually when contact pressure.

(3) through checking repeatedly, the structural design gap of male and fomale(M﹠F) should be controlled at 0.05 ± 0.02, and joint shell flange end flange width generally should be 3～10mm.This is the possibility that prevents that the layman from can not tighten symmetrically equably simultaneously when screw is tightened in installation.Compaction forces contacts to make around device panel and the connector flange aperture equably as far as possible.

The utility model has the advantages that:

1. the flange back plane improves and to be designed to male and fomale(M﹠F), and contact nonlinear is greatly improved, design ingenious, effectively reduce third order intermodulation;

2. joint shell internal diameter bottom is provided with spline; To strengthen the stationarity of inner wire;

The utility model product and original product compare, through the authoritative department testing authentication: original product PIM3 value generally only between 110dBm～115dBm, the whole test results of product of the present invention all 〉=120dBm.(1dBm approximates 43dBc)

Description of drawings

Below in conjunction with accompanying drawing the utility model product is further described.

Fig. 1 is the contact force characteristic pattern of the no concave-convex face of original product;

Fig. 1 is original product mounting structure figure a);

Fig. 1 b) is Fig. 1 stress figure a);

Fig. 2 is contact nonlinear surface and electronic circuit illustraton of model thereof;

Fig. 2 is the state diagram of Metal Contact face water conservancy diversion a);

Fig. 2 b) is Fig. 2 equivalent circuit diagram a);

Fig. 3 is the schematic diagram of contact nonlinear;

Fig. 4 is the contact force characteristic pattern that male and fomale(M﹠F) is arranged;

Fig. 4 is mounting structure figure of the present utility model a);

Fig. 4 b) is Fig. 4 stress figure a);

Fig. 5 is a main pseudosection of the present utility model;

Fig. 6 is the left view of Fig. 5;

Fig. 7 is the A-A cutaway view of Fig. 5;

Fig. 8 is the B place partial enlarged drawing of Fig. 5.

Among the figure: 1, joint shell; 11, be with externally threaded interface; 111, circular groove; 12, flange; 121, male and fomale(M﹠F); 122, flange; 13, spline; 2, inner wire; 3, insulator; 4, connector flanged plate; 5, mounting panel.

Embodiment

Embodiment one:

From Fig. 5 to Fig. 8 as can be seen, a kind of syndeton of low-intermodulation rf coaxial connector, comprise joint shell 1, inner wire 2, insulator 3, an end of joint shell 1 is being with externally threaded interface 11 inboards that three circular grooves 111 are arranged for being with externally threaded interface 11; The other end of joint shell 1 is a flange 12, and flange 12 back planes are designed to male and fomale(M﹠F) 121, and the structural design gap of male and fomale(M﹠F) 121 should be controlled at 0.03mm; Joint shell 1 bottom is provided with a spline 13; The partial design of inner wire 2 outside flange 12 ends are extended out insulator 3 becomes external screw thread, and joint shell flange end flange 122 width are designed to 3mm.

Embodiment two:

From Fig. 5 to Fig. 8 as can be seen, a kind of syndeton of low-intermodulation rf coaxial connector, comprise joint shell 1, inner wire 2, insulator 3, an end of joint shell 1 is being with externally threaded interface 11 inboards that three circular grooves 111 are arranged for being with externally threaded interface 11; The other end of joint shell 1 is a flange 12, and flange 12 back planes are designed to male and fomale(M﹠F) 121, and the structural design gap of male and fomale(M﹠F) 121 should be controlled at 0.05mm; Joint shell 1 bottom is provided with six splines 13; The partial design of inner wire 2 outside flange 12 ends are extended out insulator 3 becomes external screw thread, and joint shell flange end flange 122 width are designed to 7mm.

Embodiment three:

From Fig. 5 to Fig. 8 as can be seen, a kind of syndeton of low-intermodulation rf coaxial connector, comprise joint shell 1, inner wire 2, insulator 3, an end of joint shell 1 is being with externally threaded interface 11 inboards that three circular grooves 111 are arranged for being with externally threaded interface 11; The other end of joint shell 1 is a flange 12, and flange 12 back planes are designed to male and fomale(M﹠F) 121, and the structural design gap of male and fomale(M﹠F) 121 should be controlled at 0.07mm; Joint shell 1 bottom is provided with ten splines 13; The partial design of inner wire 2 outside flange 12 ends are extended out insulator 3 becomes external screw thread, and joint shell flange end flange 122 width are designed to 10mm.

The utility model product joint shell 1, inner wire 2 material therefors are metal materials; Insulator 3 material therefors are plastics; Joint shell flange end flange 122 width generally are designed to 3～10mm, and this is the possibility that prevents that the layman from can not tighten symmetrically equably simultaneously when screw is tightened in installation.

Claims (5)

1. the syndeton of a low-intermodulation rf coaxial connector, comprise joint shell [1], inner wire [2], insulator [3], wherein an end of joint shell [1] is for being with externally threaded interface [11], the other end of joint shell [1] is flange [12], it is characterized in that: be designed to male and fomale(M﹠F) [121] at flange [12] back plane.

2. the syndeton of low-intermodulation rf coaxial connector according to claim 1, it is characterized in that: the structural design gap of described flange male and fomale(M﹠F) [121] should be controlled at 0.05mm ± 0.02mm.

3. the syndeton of low-intermodulation rf coaxial connector according to claim 1, it is characterized in that: described joint shell flange end flange [122] width is designed to 3～10mm.

4. the syndeton of low-intermodulation rf coaxial connector according to claim 1 is characterized in that: spline [13] is set bottom the described joint shell [1].

5. the syndeton of low-intermodulation rf coaxial connector according to claim 1 is characterized in that: one to ten of spline is set bottom the described joint shell [1].

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