CN204373819U - Based on hyperacoustic electric connector contact pressure tester - Google Patents

Abstract

Based on hyperacoustic electric connector contact pressure tester, described tester comprises installation frame body and test circuit, installation frame body comprises test product fixture, riser and base platform for clamping electric connector to be measured, riser is arranged on base platform, riser has installation through hole, test product fixture is arranged in the installation through hole of riser, and test product fixture is tubular; Test circuit comprises single-chip microcomputer, spike pulse driving circuit, ultrasonic generator, ultrasonic receiver, oscillograph, and single-chip microcomputer, spike pulse driving circuit, ultrasonic generator are connected successively, and ultrasonic receiver is connected with oscillograph.

Description

Based on hyperacoustic electric connector contact pressure tester

Technical field:

The utility model belongs to a kind of contact method of testing of electromechanical compo product (electric connector) and performs the electric connector contact contact tester of the method.

Background technology:

Electric connector is used to termination conductor and carries out plugging together and being separated with corresponding complementary elements, and wherein contact element comprises contact pin and jack, is the key element of electric connector.Whether contact element possesses the contact reliability whether whether reliable and stable and electric conductivity of good structure, contact well directly has influence on electric connector.Contact resistance is the leading indicator that reflection contact reliability and contact performance are degenerated.And the factor affecting contact resistance value is a lot, comprise contact value, contact area, contact material performance etc., therefore carry out needing to detect accurately these indexs when electric contactor contact reliability detects, wherein contact is one of important performance index of electric connector, contact reduction can cause contact resistance to increase, and reduces the contact reliability of electric connector.Zhou Qixiang refer to three kinds of traditional methods and comprises in " contact of connector and detection thereof ": 1) to annular contact part, normally adds gauge pin with a survey gram weights, detects contact.The withdrawal force of what this method was in fact detected is jack, also the stiction (relative friction coefficient of jack and gauge pin and the stowed value of normal pressure) of jack, the so-called contact that this detection method measurement depending on the character of surface of jack and gauge pin obtains, its result is not bery accurate.2), when measuring the contact of blade contact, some employing little springs claim; Some employing gram measurers is surveyed, by simple test instrument measurement form with a set of relay, signal lamp and reed etc., the shortcomings such as though said method is easy and simple to handle, measurement result also exists inaccurate, and limitation is large, practical value is little.3) a kind of test macro of the test printed board connector be made up of spring, hinge and lever.This system is primarily of spring.This system sensitivity is high, can expand by multistation, can not realize the measurement of minimum range; For the connector contact of difformity feature, need to change fixture, operate relatively loaded down with trivial details; And having certain " destruction " effect to detection piece, after test, test specimen should not use.

Su Jun, Wang Qiping propose a kind of test macro based on Laser speckle interferometry for measurement amount electric connector " sickle " contact spring contact in " measurement of electric connector contact pressure and wearing and tearing transformation model ".This system is primarily of compositions such as scanning electron microscope, contact spring and light path systems.In order to when ensureing to plug together, laser can be irradiated to the side of reed, need the encapsulating material heart of its side to peel off, expose contact spring, and stick enough brightness and flexible reflecting piece in its side.Although the accuracy of systematic survey can ensure, but, test operating procedure more complicated: first, use Laser speckle interferometry for measurement amount, the screen placed by double exposure and ad-hoc location obtaining poplar formula width of fringe, secondly, calculating the microdeformation of electric connector contact reed when plugging, finally, contact is released based on when 3 hypothesis.

Find under study for action, for adopting the electric connector splitting slot type jack, the complex situations because of electric connector contact surface are difficult to adopt said method to carry out the measurement of contact, cause the detection be difficult to the stress relaxation phenomenon under jack long-term work.Therefore explore the method that the new contact better can splitting the electric connector of slot type jack to employing detects, become in prior art the problem needing to solve.

Find in early-stage Study, contact is detected, in conjunction with the existing detection to other parameters, better can reflect that contact reliability and contact performance are degenerated, but existing detection method, is all difficult to realize effectively detecting this index on the electric connector splitting slot type jack.

Ultrasound wave stress mornitoring system based on Sound elasticity principle has been widely used in as the detection of workpiece unrelieved stress, bolt stress monitoring, the detection of pressure vessel internal pressure, but split for adopting the equipment that this contact pin of electric contactor of slot type jack and jack are point cantact, its contact directly cannot obtain simply by contact stress.

Therefore, there is provided one can carry out test product installation, disassembling section fast, steadily, easily, method of testing and the instrument that accurately, nondestructively can measure again electric connector contact pressure while of improving test efficiency, minimizing labour intensity have become problem demanding prompt solution in prior art.

Utility model content

The utility model object is large for electric connector contact contact test job amount in current techniques, and the defect that measuring accuracy is lower, the utility model provides a kind of electric connector contact contact tester.Solve the Dynamic Non-Destruction Measurement problem of closed close-fitting electric connector contact contact, solve electric connector contact normally plug together contact under state accurately and easy detection.

The utility model discloses a kind of based on hyperacoustic electric connector contact method for testing pressure, the jack of described electric connector is for splitting slot type jack, described slot type jack of splitting is and on the hole wall of cylindric jack, has at least two vertically split groove, the opening of the opening and jack of splitting groove is offered in the same way, and the hole wall of jack front end is divided into several reeds, it is characterized in that described method needs carry out at electric connector jack lateral surface mounting ultrasonic generator and ultrasonic receiver, the ultrasonic signal that described ultrasonic generator is launched is compressional wave signal, the compressional wave Signal reception direction of compressional wave signal transmit direction and ultrasonic receiver is positioned in the same plane perpendicular to jack perforate direction, described plane and jack inside surface intersection are between the receptacle pins touching position when jack openings and contact pin are inserted completely, described ultrasound wave compressional wave signal waveform is spike pulse signal, and described ultrasonic frequency is 1.2-5MHz, preferred 2.5MHz, and described method comprises the following steps:

1, detect the travel-time t of compressional wave in ultrasonic signal when contact pin does not insert respectively ₀it is obtained not by longitudinal wave velocity V under stress condition according to electric connector jack and contact pin material _t0, transverse wave velocity V _t0and density p ₀;

2, according to following formulae discovery contact pressure F

$F=\frac{{\mathrm{WH}}^2}{0.013L}\mathrm{\σ}---\left(1\right)$

$\mathrm{\σ}=\frac{2}{{\mathrm{kt}}_0}\mathrm{\Δt}---\left(2\right)$

T ₀for ultrasonic compressional wave propagation time when contact pin does not insert, Δ t detects the ultrasonic compressional wave propagation time difference obtained before and after contact pin insertion jack,

Wherein k is electric connector elastic constant, $k=\frac{\frac{4\mathrm{\λ}+10\mathrm{\μ}+4m}{\mathrm{\μ}}+\frac{2l-3\mathrm{\λ}-10\mathrm{\μ}-4m}{\mathrm{\λ}+2\mathrm{\μ}}}{3\mathrm{\λ}+2\mathrm{\μ}}---\left(3\right),$ In formula, L is length of spring leaf, and H is jack wall thickness, the reed width of W jack, and σ is contact stress.

λ, μ are the second order elasticity coefficient of electric connector jack material, and n, m, l are three rank elasticity coefficient of electric connector jack material.

Described method of testing, is characterized in that, adopts ultrasonic coupling agent to fill the gap at ultrasonic generator and ultrasonic receiver and jack exterior surface place.

Described method of testing, is characterized in that the second order elasticity coefficient lambda of electric connector jack material, μ calculates with following formula

$\mathrm{\μ}={\mathrm{\ρ}}_0{V}_{t0}^2---\left(4\right)$

$\mathrm{\λ}={\mathrm{\ρ}}_0(V_{l0}^2-2V_{t0}^2)---\left(5\right).$

Described method of testing, is characterized in that three rank elasticity coefficient l of described electric connector jack material, m, n, tests by the following method:

Four-prism shape sample is made with the material forming electric connector jack, x is respectively with sample length direction, y, z-axis, ultrasonic signal emitters and receiver are fixed bottom surface on sample, ultrasonic signal transmit direction is parallel to sample x-axis, records the ultrasonic compressional velocity of wave propagation V of sample under axial stress respectively _xx, vertical polarization shear wave velocity of propagation V _xy, horizontally polarized shear velocity of propagation V _xz, the axial stress σ of sample _zz, and in conjunction with above-mentioned physical quantity and following formulae discovery l, m, n:

$\frac{V_{\mathrm{xz}}-V_{\mathrm{xy}}}{V_{t0}{\mathrm{\σ}}_{\mathrm{zz}}}=\frac{4\mathrm{\μ}+n}{8{\mathrm{\μ}}^2}---\left(6\right)$

$\frac{V_{\mathrm{xz}}-V_{t0}}{V_{t0}{\mathrm{\σ}}_{\mathrm{zz}}}=\frac{\mathrm{\λ}+3\mathrm{\μ}+m+\frac{\mathrm{\λu}}{4\mathrm{\μ}}}{2\mathrm{\μ}(3\mathrm{\λ}+2\mathrm{\μ})}---\left(7\right)$

$\frac{V_{\mathrm{xx}}-V_{l0}}{V_{l0}{\mathrm{\σ}}_{\mathrm{zz}}}=\frac{\mathrm{\μl}-\mathrm{\λ}(m+\mathrm{\λ}+2\mathrm{\μ})}{\mathrm{\μ}(3\mathrm{\λ}+2\mathrm{\μ})(\mathrm{\λ}+2\mathrm{\μ})}---\left(8\right).$

The utility model additionally provides a kind of based on hyperacoustic electric connector contact pressure tester, described tester is used for the described arbitrary method of testing of a kind of execution, it is characterized in that described tester comprises installation frame body and test circuit, described installation frame body comprises test product fixture, riser and base platform for clamping electric connector to be measured, riser is arranged on base platform, riser has installation through hole, described test product fixture is arranged in the installation through hole of riser, and test product fixture is tubular;

Described test circuit comprises single-chip microcomputer, spike pulse driving circuit, ultrasonic generator, ultrasonic receiver, oscillograph, and single-chip microcomputer, spike pulse driving circuit, ultrasonic generator are connected successively, and ultrasonic receiver is connected with oscillograph.

Described tester, it is characterized in that described single-chip microcomputer is for generation of square-wave signal, square-wave signal is converted to spike pulse signal by described spike pulse driving circuit.

Described tester, it is characterized in that described test circuit also comprises load circuit, described load circuit comprises power supply and load, for providing for electric connector to be measured the electric current being equivalent to normal operating conditions.

The utility model compared with prior art has following main beneficial effect:

1, go for multiple type spectrum, detection that the electric connector of slot type jack is split in the employing of different model, and ultrasound wave can be propagated in any solid, therefore the kind restriction of not power connector contact element metal material, highly versatile;

2, under high in reliability, workable, detection speed is fast, detection resolution is high prerequisite, the Non-Destructive Testing of electric connector contact contact can be realized, can not damage the actual working state of detected object (contact element) close contact, and the stress distribution of any degree of depth can be surveyed, thus extrapolate contact pressure F; And by contact pressure F, means when detecting electric connector reliability and contact performance degeneration can be enriched, in conjunction with other existing Testing index, better can realize the prediction that electric connector reliability and contact performance are degenerated.

Accompanying drawing explanation

Fig. 1 is the test circuit syndeton schematic diagram of tester in embodiment 1;

Fig. 2 is the schematic front view of tester installation frame body in embodiment 1;

Fig. 3 is the schematic top plan view of tester installation frame body in embodiment 1;

Fig. 4 is that schematic diagram is looked on the right side of tester installation frame body in embodiment 1;

Fig. 5 is the fixed connection structure schematic front view of electric connector to be measured and ultrasonic generator and ultrasonic receiver in tester in embodiment 1;

Fig. 6 is that schematic diagram is looked on a fixed connection structure left side for electric connector to be measured and ultrasonic generator and ultrasonic receiver in tester in embodiment 1;

Fig. 7 is the fixed connection structure schematic top plan view of electric connector to be measured and ultrasonic generator and ultrasonic receiver in tester in embodiment 1;

In figure, 1-single-chip microcomputer, 2-spike pulse driving circuit, 3-ultrasonic generator, 4-electric connector to be measured, 5-ultrasonic receiver, 6-oscillograph, 7-load circuit, 8-test product fixture, 9-riser, 10-base platform, 41-jack, 42-contact pin, 43-insulating material.

Embodiment:

Embodiment 1:

(1) measurement of second order, three rank elastic constants:

For the tin bronze as plug jack material, it is not by the longitudinal wave velocity V under stress state _l0=3970m/s, transverse wave velocity V _t0=2122m/s, density p ₀=8.8*10 ³kg/m ³.

Second order elasticity coefficient adopts formula (4), (5) calculate

$\mathrm{\μ}={\mathrm{\ρ}}_0{V}_{t0}^2---\left(4\right)$

$\mathrm{\λ}={\mathrm{\ρ}}_0(V_{l0}^2-2V_{t0}^2)---\left(5\right).$

Plug jack material is adopted to make four-prism test block, x is respectively with sample length direction, y, z-axis, ultrasonic signal emitters and receiver are fixed bottom surface on sample, ultrasonic signal transmit direction is parallel to sample x-axis, records the ultrasonic compressional velocity of wave propagation V of sample under axial (i.e. z-axis direction) stress respectively _xx, vertical polarization shear wave velocity of propagation V _xy, horizontally polarized shear velocity of propagation V _xz, the axial stress σ of sample _zz, wherein longitudinal wave propagation direction is parallel to x-axis, and the vertical polarization shear wave direction of propagation is parallel to y-axis, and the horizontally polarized shear direction of propagation is parallel to z-axis, and in conjunction with above-mentioned physical quantity and following formulae discovery l, m, n:

$\frac{V_{\mathrm{xz}}-V_{\mathrm{xy}}}{V_{t0}{\mathrm{\σ}}_{\mathrm{zz}}}=\frac{4\mathrm{\μ}+n}{8{\mathrm{\μ}}^2}---\left(6\right)$

$\frac{V_{\mathrm{xz}}-V_{t0}}{V_{t0}{\mathrm{\σ}}_{\mathrm{zz}}}=\frac{\mathrm{\λ}+3\mathrm{\μ}+m+\frac{\mathrm{\λu}}{4\mathrm{\μ}}}{2\mathrm{\μ}(3\mathrm{\λ}+2\mathrm{\μ})}---\left(7\right)$

$\frac{V_{\mathrm{xx}}-V_{l0}}{V_{l0}{\mathrm{\σ}}_{\mathrm{zz}}}=\frac{\mathrm{\μl}-\mathrm{\λ}(m+\mathrm{\λ}+2\mathrm{\μ})}{\mathrm{\μ}(3\mathrm{\λ}+2\mathrm{\μ})(\mathrm{\λ}+2\mathrm{\μ})}---\left(8\right)$

Bring the second order calculated, three rank elastic constants into following formula

$k=\frac{\frac{4\mathrm{\λ}+10\mathrm{\μ}+4m}{\mathrm{\μ}}+\frac{2l-3\mathrm{\λ}-10\mathrm{\μ}-4m}{\mathrm{\λ}+2\mathrm{\μ}}}{3\mathrm{\λ}+2\mathrm{\μ}}---\left(3\right),$ The elastic constant of connector pin part can be obtained

k＝-0.92×10 ^-7Pa ^-1。

(2) tester structure be connected

Electric connector to be measured is the M25 type aviation plug (i.e. electric connector to be measured) that certain company produces, and its plug jack material is tin bronze, and by 4 roads, longitudinally splitting groove is divided into 4 reeds in jack hole wall front end, and anchor portion is processed to reducing.The electric connector specifications parameter to be measured adopted sees the following form

In table, weldering rim of a cup aperture is jack openings place internal diameter, and contact aperture is jack internal diameter.

In the utility model, ultrasonic generator and ultrasonic receiver all adopt 2.5P10 type normal probe, oscillograph is DS1042C type.

Tester comprises installation frame body and test circuit, described installation frame body comprises test product fixture 8, riser 9 and base platform 10 for clamping electric connector to be measured, its main depending on, overlook, the right side looks schematic diagram respectively as shown in figs. 2 to 4, described riser is L-type plate, be fixedly mounted on base platform by the base plate of L-type plate, described riser has installation through hole perpendicular to the part of base platform, and described installation through-bore axis is parallel with base platform.Test product fixture is cylindric, and be fixedly mounted on and install in through hole, holder axis direction is also parallel with base platform, and described test product holder wall has threaded securing bores, adopts set bolt to be fixed in test product fixture by threaded securing bores by electric connector to be measured,

Described test circuit comprises single-chip microcomputer 1, spike pulse driving circuit 2, ultrasonic generator 3, ultrasonic receiver 5, oscillograph 6; Single-chip microcomputer, spike pulse driving circuit, ultrasonic generator are connected successively, and ultrasonic receiver is connected with oscillograph.The P wave emission direction of ultrasonic generator and the compressional wave receive direction of ultrasonic receiver are positioned in the same plane perpendicular to jack perforate direction, and ultrasonic frequency is 2.5MHz

Test circuit also comprises load circuit 7, and described load circuit comprises power supply and load, for providing for electric connector to be measured the electric current being equivalent to normal operating conditions.

Described test circuit syndeton schematic diagram as shown in Figure 1,

When testing, divest electric connector 4 receptacle portion insulating material 43 part to be measured to expose jack 41 and be used for the fixing normal probe as ultrasonic generator and ultrasonic receiver, the fixed position of normal probe is near jack oral area and is positioned in the same plane perpendicular to jack perforate direction, and in order to measure the contact under normal operating condition, need contact pin 42 to insert in jack, and connect load circuit.In the present embodiment, hyperacoustic compressional wave signal transmit direction and ultrasound wave compressional wave receiving side signal to the angle fixed connection structure master that is 180 ° of electric connectors to be measured (three cores) and ultrasonic generator and ultrasonic receiver looks depending on a, left side, schematic top plan view is respectively as shown in Fig. 5 ~ 7.

(3) calculating of contact pressure F

In test process, after test circuit is connected:

First, when contact pin does not plug together with jack, the travel-time t of ultrasound wave compressional wave in jack is measured ₀;

Secondly, contact pin and jack are plugged together by normal operating condition, now load circuit is connected, the change in test ultrasound wave compressional wave travel-time in connector contact.Adjust oscillographic display mode, knots modification Δ t during electric connector propagation sound can be obtained.

K is brought into (2) obtain stress σ, and σ is brought into (1) contact pressure F is obtained

In formula, F is contact (unit N), σ is contact stress (unit Gpa), and L, W, H are the length of each reed of electric connector jack, width and thickness.L=10mm, W=2.7mm, H=0.6mm, t in the present embodiment ₀=2.07 μ s.

σ is in units of MPa, and F is in units of N, then the transformational relation that can obtain contact stress and contact is:

F＝7.47σ(1.1)

From the above, as long as knots modification Δ t when the change in travel-time of measuring ultrasound wave in object and sound, just can in the hope of the stress in propagation medium or contact.

The knots modification of the ultrasonic propagation velocity caused due to the stress of actual testee is all very little, general prospecting tools is difficult to detect accurate especially numerical value, thus introduce larger measuring error, so, stress in propagation medium can be tried to achieve by formula (2) with knots modification during sound and and then calculate contact, the minor alteration amount solving its ultrasonic propagation velocity gathers the key issue of difficulty.Table 1 is depicted as and utilizes the utility model to carry out electric connector contact pressure test to test the partial data obtained.

Table 1 connector contact pressure testing results

Can find out in table 1 data, for the electric connector to be measured adopting same structure receptacle pins, the contact value consistance that the method for testing adopting the utility model embodiment to provide and testing tool carry out testing the different jacks obtained is better, relative deviation≤5%, illustrates that the method and instrument can effectively for the tests of electric connector contact pressure.

Claims (3)

1. one kind based on hyperacoustic electric connector contact pressure tester, it is characterized in that, described tester comprises installation frame body and test circuit, described installation frame body comprises test product fixture, riser and base platform for clamping electric connector to be measured, riser is arranged on base platform, riser has installation through hole, described test product fixture is arranged in the installation through hole of riser, and test product fixture is tubular;

Described test circuit comprises single-chip microcomputer, spike pulse driving circuit, ultrasonic generator, ultrasonic receiver, oscillograph, and single-chip microcomputer, spike pulse driving circuit, ultrasonic generator are connected successively, and ultrasonic receiver is connected with oscillograph.

2. tester as claimed in claim 1, it is characterized in that described single-chip microcomputer is for generation of square-wave signal, square-wave signal is converted to spike pulse signal by described spike pulse driving circuit.

3. tester as claimed in claim 1 or 2, it is characterized in that described test circuit also comprises load circuit, described load circuit comprises power supply and load, for providing for electric connector to be measured the electric current being equivalent to normal operating conditions.