CN207882345U - PCB automatic impedance-testing machines - Google Patents

Abstract

The utility model provides a kind of PCB automatic impedance-testings machine, and PCB automatic impedance-testing machines include：Test platform；Substrate absorption device is arranged on test platform, and substrate absorption device includes the bottom plate and panel of stacked setting from bottom to up, air inlet is provided on bottom plate, side on air inlet is connected with negative pressure source, and several through-holes are provided on panel, circuit board to be detected is placed on panel；Measuring head, is movably disposed on test platform and treats detection circuit board and be detected；Substrate absorption device further includes the flow distribution plate being arranged between bottom plate and panel, and the air-flow on flow distribution plate on the region of air inlet passes through area by the air-flow that area is less than on flow distribution plate on the region far from air inlet.The technical solution of the utility model effective solution prior art pcb board suction base negative pressure loses serious problem.

Description

PCB automatic impedance-testing machines

Technical field

The utility model is related to PCB technical field of measurement and test, and in particular to a kind of PCB automatic impedance-testings machine.

Background technology

With bringing for 5G communication eras, the working frequency of signal reaches 30GHz, individual channel data communication rates reach The requirement of the magnitude of 10Gbps, the signal integrity of pcb board will be higher and higher.Single-ended to PCB or differential signal characteristic resistance Anti- measurement method is represented practical single-ended in plate by the characteristic impedance value of manual measurement pcb board side coupon (sample) lines Or the impedance value of difference lines, specifically, trained technical staff holds differential probe or single-ended probe, is found by human eye Single-ended or difference measuring point, a small amount of representative measuring point of selection carry out impedance measurement or only measure the impedance lines of pcb board edges of boards. Above-mentioned artificial impedance measurement mode has the following disadvantages：The resultant error of measurement is big；It can not accomplish that measuring point measures entirely in pcb board； The artificial pressure for acting on measuring point is uneven, causes to have measuring point pad and pricks trace damage；Working efficiency is low, and the labour of worker is strong Degree is big.Therefore, it can be eliminated by the way of manual measurement impedance, and then it is single-ended or poor to be directly measured in pcb board each The full-automatic impedance measurement mode of line-dividing replaces.

In the prior art, the full-automatic testing impedance machine of PCB impedances includes pcb board suction base, and pcb board is inhaled by pcb board The mode that attached pedestal air-breathing generates negative pressure is fixed, and specifically, pcb board suction base generally includes negative-pressure adsorption platform and sets The negative pressure source below negative-pressure adsorption platform is set, negative pressure source applies pcb board by negative-pressure adsorption platform the uniformity of adsorption capacity As one of the most critical factor of influence testing result.For this purpose, pcb board adsorbs negative pressure platform usually in flat surface in the prior art Equally distributed multiple stomatas are opened up on plate, to obtain the uniform adsorption capacity to pcb board.However it finds in actual use It is really not so, it still remains to the non-uniform defect of pcb board adsorption capacity, this also becomes those skilled in the art to the difficulty of solution One of topic.Those skilled in the art also have to the problem of solution：Absorption negative pressure tabletop of platform generally use face in the prior art Plate and bottom plate stack again by the fixed structure of outline border, but due in production installation process outline border and panel, outline border and bottom plate it Between easily exist installation gap, therefore gas easily from built-in edge reveal, to cause absorption cavity poor sealing, cause negative pressure to damage It loses serious；Footprint is larger, therefore when being actually used in absorption compared with small area substrate, and negative pressure loss is serious, both wastes resource Make pcb board that can not be sucked by table top again.

Utility model content

The main purpose of the utility model is to provide a kind of PCB automatic impedance-testings machines, to solve PCB in the prior art Plate suction base negative pressure loses serious problem.

To achieve the above object, the utility model provides a kind of PCB automatic impedance-testings machine, including：Test platform；Base Plate adsorbent equipment is arranged on test platform, and substrate absorption device includes the bottom plate and panel of stacked setting from bottom to up, bottom plate On be provided with air inlet, the side on air inlet is connected with negative pressure source, and several through-holes are provided on panel, places and needs on panel Detection circuit board；Measuring head, is movably disposed on test platform and treats detection circuit board and be detected；Substrate adsorption fills It further includes the flow distribution plate being arranged between bottom plate and panel to set, and the air-flow on flow distribution plate on the region of air inlet passes through area Pass through area less than the air-flow on the region far from air inlet on flow distribution plate.

Further, be provided with the not equal stomata in aperture on flow distribution plate, the air vent aperture far from air inlet be more than close into The air vent aperture of gas port.

Further, stomata is rectangular to external diffusion centered on air inlet, the stomata on the same rectangle Aperture is equal, equidistantly distributed between each rectangle.

Further, the stomata on flow distribution plate is distributed centered on air inlet in spoke shape.

Further, the stomata spacing on each spoke straight line is distributed using air inlet as starting point in arithmetic progression, each Air vent aperture on spoke straight line is that starting point is distributed in Geometric Sequence using air inlet.

Further, the stomata gap on flow distribution plate on the region far from air inlet is less than on the region of air inlet Stomata gap.

Further, it is provided with the equal stomata in aperture on flow distribution plate, the gas on flow distribution plate on the region far from air inlet Interporal lacuna is less than the stomata gap on the region of air inlet.

Further, PCB automatic impedance-testings machine further includes：The linear module of X-axis, including be oppositely arranged on test platform Two X-axis slide rails, can reciprocating linear moves in two X-axis slide rails installation pedestal and the X-axis that is arranged on test platform Driving structure, X-axis driving structure drive installation pedestal reciprocating linear in X-axis slide rail to move；Installation pedestal includes substrate and edge The side plate of two edges setting in substrate length direction；The linear module of Y-axis, including be arranged on each side plate Y-axis sliding rail, can The sliding part and the Y-axis driving structure in installation pedestal that reciprocating linear moves on two Y-axis sliding rails, Y-axis driving knot Structure drives sliding part reciprocating linear on Y-axis sliding rail to move；Z axis module, including two Z being oppositely arranged on sliding part Axis sliding rail the bearing of reciprocating linear movement and the Z axis driving structure being arranged on sliding part, Z axis can drive in two Z axis slide rails Dynamic structure drives bearing reciprocating linear in Z axis slide rail to drive, and measuring head is mounted on bearing.

Further, the top surface of side plate and the bottom surface of Y-axis sliding rail are the polished surface that a pair of matched is closed.

Further, Y-axis driving structure includes：Y-axis motor is arranged in installation pedestal one end；Y-axis lead screw, is set to two Extend between a side plate and along installation pedestal length direction, Y-axis lead screw is driven by y-axis motor and rotated, the both ends point of Y-axis lead screw One connecting seat that Y-axis lead screw and substrate are fixed is not installed；Y-axis drive block is arranged on Y-axis lead screw and in Y-axis silk It is moved along Y-axis lead screw reciprocating linear under bar rotation driving, Y-axis drive block is fixedly installed with sliding part.

Further, measuring head includes rotating disk and installation probe switching device on the rotating pan, bearing be equipped with The rotational structure that rotating disk is drivingly connected, probe switching device include：Supporter；First probe portion, opposite supporter are removable Setting, the first probe portion have at least two first test positions, the first probe portion can at least two first test positions it Between mobile handoff；At least two second probe portions, opposite supporter are movably arranged, and each second probe portion has to be visited with first Second test position of needle portion cooperation and the evacuation position in the first probe portion of evacuation and the cooperation of remaining second probe portion, second visits Needle portion can the second test position and evacuation position between mobile handoff.

Further, probe switching device further includes the first driving for being set on the support and being connect with the first probe portion Mechanism, the first driving mechanism drive the first probe portion to be switched between at least two first test positions.

Further, probe switching device further includes the connection being connected between the first driving mechanism and the first probe portion Portion, the first driving mechanism drive the first probe portion to move by the way that drive connection portion is mobile in the horizontal direction.

Further, probe switching device further includes the second driving mechanism being connect with each second probe portion, and second drives Motivation structure drives each second probe portion to be switched between the second test position and evacuation position.

Further, the second driving mechanism drives the second probe portion vertically to move, and evacuation position is higher than the second inspection Location is set and the first test position.

Further, the second driving mechanism is the switching part being fixed on interconnecting piece, and switching part has climbing structure, cutting It changes in the moving process in portion, climbing structure jacks up the second probe portion so that the second probe portion switches to evacuation from the second test position Position.

Further, switching part tool there are two be obliquely installed relative to vertical direction and inclined-plane that its inclined direction is opposite and The plane being connected between two inclined-planes, two inclined-planes formed climbing structures and respectively on the voussoir in two the second probe portions Coordinate inclined-plane cooperation.

Further, test platform is equipped with the positioning calibration assemblies positioned at circuit board side to be detected, positions calibration group Part includes：Mounting plate has the first avoid holes；Glass calibration plate, be mounted on mounting plate top and with the position of the first avoid holes Correspondence is set, glass calibration plate is equipped with the groove face for calibrating probe location；Camera is arranged in the lower section of mounting plate and the The position of one avoid holes corresponds to.

Further, test platform is equipped with the impedance correction plate positioned at circuit board side to be detected, on impedance correction plate Equipped with multipair test point, for measuring real impedance values.

Further, PCB automatic impedance-testings machine further includes support base, and test platform is arranged in support base.

Technical solutions of the utility model have the following advantages that：By being provided with flow distribution plate between panel and bottom plate, shunt Air-flow on plate at air inlet is less than far from the air-flow at air inlet by area through area, can be uniform by flow distribution plate The adsorptive pressure in each region avoids the occurrence of and is more than the feelings far from the adsorptive pressure at air inlet close to adsorptive pressure at air inlet Condition.

Description of the drawings

It, below will be right in order to illustrate more clearly of specific embodiment of the present invention or technical solution in the prior art Specific implementation mode or attached drawing needed to be used in the description of the prior art are briefly described, it should be apparent that, it is described below In attached drawing be that some embodiments of the utility model are not paying creativeness for those of ordinary skill in the art Under the premise of labour, other drawings may also be obtained based on these drawings.In the accompanying drawings：

Fig. 1 shows the stereoscopic schematic diagram of the embodiment of PCB automatic impedance-testings machine according to the present utility model；

Fig. 2 shows the partial schematic diagrams of the PCB automatic impedance-testing machines of Fig. 1；

Fig. 3 shows the stereoscopic schematic diagram for removing oscillograph and supporting rack of the PCB automatic impedance-testing machines of Fig. 2；

Fig. 4 shows the schematic front view of the substrate absorption device of the PCB automatic impedance-testing machines of Fig. 3；

Fig. 5 shows the decomposition diagram of the substrate absorption device of Fig. 4；

Fig. 6 shows the bottom plate stereogram of the substrate absorption device of Fig. 4；

Fig. 7 shows the stereogram of the flow distribution plate of the substrate absorption device of Fig. 4；

Fig. 8 shows the stereogram of the panel of the substrate absorption device of Fig. 4；

Fig. 9 shows the linear module of installation pedestal, Y-axis, z axis module and the survey of the PCB automatic impedance-testing machines of Fig. 3 Try the stereogram of head；

Figure 10 shows the stereogram of the installation pedestal of Fig. 9 and the linear module of Y-axis；

Figure 11 shows the partial perspective view of the installation pedestal of Figure 10 and the linear module of Y-axis；

Figure 12 shows the stereogram of the bearing of Fig. 9, rotational structure and measuring head；

Figure 13 shows the stereogram of the measuring head of Figure 12；

Figure 14 shows the schematic front view of the measuring head of Figure 13.

Figure 15 shows the stereogram of the probe switching device of Figure 13；

Figure 16 shows the schematic diagram of another angle of the probe switching device of Figure 15；

Figure 17 shows the dimensional structure diagrams of the switching part of the probe switching device of Figure 16；

Figure 18 shows the dimensional structure diagram of the interconnecting piece of the probe switching device of Figure 16；

Figure 19 shows the stereoscopic schematic diagram of the calibration module of Fig. 3；

Figure 20 shows the vertical view of the glass calibration plate of Figure 19.

Wherein, the reference numeral in above-mentioned attached drawing is：

10, support base；20, test platform；

30, substrate absorption device；31, bottom plate；311, bottom plate fixed frame；312, air inlet；313, mounting hole；314, first Positioning protrusion；32, flow distribution plate；321, stomata；33, panel；331, panel fixed frame；332, through-hole；333, the second positioning protrusion； 34, non-woven fabrics；35, flange；36, fixing piece；37, pipeline；38, control valve；39, negative pressure source；

40, measuring head；41, rotating disk；42, supporter；43, the first driving mechanism；441, the first probe base；442, first Probe；451, the second probe base；452, the second probe；453, guide rod；454, voussoir；455, return unit；46, switching part； 461, inclined-plane；462, plane；463, slot hole；47, interconnecting piece；48, mounting bracket；49, displacement sensor；51, rotational structure；

60, the linear module of X-axis；61, X-axis slide rail；62, installation pedestal；621, substrate；6211, boss；6212, hole；622、 Side plate；63, X-axis driving structure；631, X-axis motor；632, X-axis lead screw；

70, the linear module of Y-axis；71, Y-axis sliding rail；72, sliding part；722, support arm；73, Y-axis driving structure；731, Y-axis electricity Machine；732, Y-axis lead screw；733, Y-axis drive block；734, connecting seat；

80, z axis module；81, Z axis slide rail；82, bearing；83, Z axis driving structure；84, square block；

91, mounting plate；92, glass calibration plate；93, camera；94, impedance correction plate；95, locating module is detected；

100, circuit board to be detected；110, oscillograph；120, outer casing framework；130, supporting rack.

Specific implementation mode

The technical solution of the utility model is clearly and completely described below in conjunction with attached drawing, it is clear that described Embodiment is the utility model a part of the embodiment, instead of all the embodiments.Based on the embodiments of the present invention, originally The every other embodiment that field those of ordinary skill is obtained without making creative work, belongs to this practicality Novel protected range.

As shown in Fig. 1, Fig. 4, Fig. 6 and Fig. 8, the PCB automatic impedance-testing machines of the present embodiment include：Test platform 20, base Plate adsorbent equipment 30 and measuring head 40, substrate absorption device 30 are arranged on test platform 20, and measuring head 40 is movably disposed On test platform 20 and treats detection circuit board 100 and be detected；Substrate absorption device 30 includes being stacked setting from bottom to up Bottom plate 31 and panel 33, be provided with air inlet 312 on bottom plate 31, the side on air inlet 312 is connected with negative pressure source, panel 33 On be provided with several through-holes 332, circuit board 100 to be detected is placed on panel 33；Substrate absorption device 30 further includes that setting exists Flow distribution plate 32 between bottom plate 31 and panel 33, the air-flow on flow distribution plate 32 on the region of air inlet 312 are small by area Pass through area in the air-flow on the region far from air inlet 312 on flow distribution plate 32.Wherein, Fig. 8 merely illustrates one of panel 33 Through-hole 332 on angle.

Substrate absorption device 30 generates negative pressure to fix circuit board to be detected by air-breathing, prevents pcb board to be detected from existing The mobile position inaccuracy for causing probe when measuring occurs during test and is unable to measure.By panel and bottom plate it Between be provided with flow distribution plate, the air-flow on flow distribution plate at air inlet is less than by area passes through face far from the air-flow at air inlet Product, by flow distribution plate can uniform each region adsorptive pressure, avoid the occurrence of the adsorptive pressure at the air inlet and be more than far from air inlet Mouthful at adsorptive pressure the case where.

As shown in Figure 4 and Figure 5, the air inlet 312 being connect with negative pressure source 39 is provided on bottom plate 31, the setting of negative pressure source 39 exists The side of air inlet 312, panel 33, which is arranged on the other side of air inlet 312, panel 33, is provided with several through-holes 332.Wherein Flow distribution plate 32 is set between bottom plate 31 and panel 33.33 another side surface of panel is provided with non-woven fabrics 34, on non-woven fabrics 34 Several ventholes are provided with, wherein non-woven fabrics 34, which tiles, is fixed on the surface of panel 33, to prevent gas from the side of non-woven fabrics 34 Edge is revealed to influence adsorption capacity, is fixed using sealing material and the sealing of panel 33 at the edge of non-woven fabrics 34, wherein sealing material The glue such as glass cement or other binders can be used in material, avoid the leakage of gas, improve adsorption efficiency.Since substrate has There is certain electric conductivity, and the conductive materials such as panel generally use aluminium alloy are made, therefore one layer of nonwoven is laid on panel 33 Cloth 34, both can uniformly device for thinning surface adsorptive pressure, substrate and panel can be also dielectrically separated from by non-woven fabrics.By dividing Fluid sealant is arranged with the edge of bottom plate and plate contact in flowing plate, avoids the leakage of gas, improves adsorption efficiency.

In the present embodiment, as shown in Figure 6 and Figure 8, it is right with flow distribution plate 32 to be respectively arranged on bottom plate 31 and panel 33 The bottom plate fixed frame 311 and panel fixed frame 331 that should be arranged, are enclosed between bottom plate fixed frame 311 and panel fixed frame 331 It is useful for the chamber of installation flow distribution plate 32.Be located in its bottom plate 31 in chamber be provided in one side corresponding with flow distribution plate 32 it is more A first positioning protrusion 314, the first positioning protrusion 314 are used to support flow distribution plate 32.Be located on same panel 33 in chamber with Multiple second positioning protrusion 333, the second positioning protrusion 333 and the first positioning protrusion are also equipped in 32 corresponding one side of flow distribution plate 314 common fixed flow distribution plates 32.

The both ends of the surface of flow distribution plate 32 are respectively embedded into the bottom plate fixed frame 311 and panel fixed frame 331 of bottom plate 31 and panel 33 In, while gas influences the adsorption effect of adsorbent equipment from the edge leakage of fixed frame in order to prevent, is sealed using sealing material The glue such as glass cement or other binders can be used in flow distribution plate 32 and each fixed frame, wherein sealing material.

As shown in fig. 7, aperture not equal stomata 321 is provided on flow distribution plate 32 in the present embodiment, wherein far from air inlet The air vent aperture of mouth is more than the air vent aperture close to air inlet 312.Stomata 321 on flow distribution plate 32 is centered on air inlet 312 Radially it is distributed.The negative pressure flow that wherein size of centre porosity 321 is generated according to negative pressure source determines that every radiates with flow velocity Stomata spacing on straight line is distributed using centre porosity as starting point in arithmetic progression, such as is determined with 1.0~1.5 times of arithmetic progression Determine the pitch-row between stomata.Air vent aperture on every radiation straight line is distributed using centre porosity as starting point in Geometric Sequence.Example The size of the stomata on a radiation straight line is such as determined with 1.2~1.5 Geometric Sequence.

Certainly, the stomata on flow distribution plate can be also uniformly distributed, such as centered on air inlet 312, and each stomata 321 is with rectangle Shape is to external diffusion, and the aperture of the stomata on the same rectangle is equal, equidistantly distributed between each rectangle.Close to air inlet Air vent aperture on 312 rectangle is less than the air vent aperture on the rectangle far from air inlet 312.

In the present embodiment, the air inlet 312 on bottom plate 31 is connect by pipeline 37 with negative pressure source 39, is arranged on pipeline 37 There is control valve 38.The side of wherein air inlet 312 is provided with connecting flange 35 and fixing piece 36, and one end of connecting flange 35 passes through Mounting hole 313 is fixedly attached on bottom plate 31, and the other end of connecting flange 35 is fixedly attached to by fixing piece 36 on pipeline 37. There are two the settings of air inlet 312 in the present embodiment, and two air inlets 312 are distributed in two different binding domains of bottom plate 31, Two binding domains in the present embodiment are equally distributed two rectangle binding domains, two of which air inlet on bottom plate 31 312 are connect by two pipelines 37 with two negative pressure sources 39 respectively, and control valve 38 is both provided on each pipeline 37.Certainly, bottom Two binding domains on plate 31 can be smaller with uneven distribution, such as another larger area of an area.In the present embodiment Negative pressure source 39 be negative pressure occur motor, control valve 38 be normally opened big flow solenoid valve.It is of course also possible to which multiple adsorption zones are arranged Domain, each binding domain are both provided with air inlet and connect the pipeline of air inlet and negative pressure source, the pipeline of each binding domain On be both provided with independent control valve, the break-make for controlling air-flow, can by open in one or partial adsorbates region with Control valve on the pipeline of negative pressure source connection, other are not selected to close by the control valve on the pipeline of the binding domain of substrate covering It closes, it is possible thereby to economize on resources, avoids unnecessary waste.

In the present embodiment, the gap between the stomata on flow distribution plate on the region far from air inlet is less than close to air inlet Region on stomata between gap, i.e., on flow distribution plate close to air inlet stomatal frequency be less than far from air inlet stomata it is close Degree, the stomata control by the way that different densities are arranged passes through the flow area of different zones on flow distribution plate, with uniform different zones The case where adsorbing air pressure, avoiding the occurrence of the adsorptive pressure that the adsorptive pressure at air inlet is more than at separate air inlet.

In the present embodiment, it is respectively provided at the adjacent two edges of panel and treats what detection circuit board was positioned Positioning strip, the adjacent both sides that two positioning strips treat detection circuit board respectively are limited, and positioning is more acurrate.

As the embodiment of replacement, more than two multiple rectangle binding domains are also provided on bottom plate 31, In the area of each binding domain can be equal or different, air inlet is both provided in each binding domain, each air inlet is logical Piping 37 is connect with negative pressure source 39, and independent control valve 38 is both provided on each pipeline 37.When substrate area to be operated When smaller, the control valve on the pipeline being connected to negative pressure source in one or partial adsorbates region can be opened, other are not by substrate Control valve selection on the pipeline of the binding domain of covering is closed, it is possible thereby to economize on resources, avoids unnecessary waste.

As the embodiment of replacement, the equal stomata in aperture is may also set up on flow distribution plate, it is wherein separate on flow distribution plate The gap between stomata on the region of air inlet is less than the gap between the stomata on the region of air inlet, i.e. flow distribution plate The upper stomatal frequency close to air inlet is less than the stomatal frequency far from air inlet, and the stomata control by the way that different densities are arranged passes through The flow area of different zones on flow distribution plate avoids the occurrence of the suction at air inlet with the absorption air pressure of uniform different zones Enclosure pressure is more than the case where adsorptive pressure at separate air inlet.

Substrate absorption device provided by the utility model, by being provided with flow distribution plate between panel and bottom plate, by dividing The density of distributed pores in flowing plate is arranged or the setting of the aperture of stomata so that the air-flow on flow distribution plate at air inlet is logical Area is crossed to be less than far from the air-flow at air inlet through area, by flow distribution plate can uniform each region adsorptive pressure, avoid out The case where being now more than the adsorptive pressure at separate air inlet close to adsorptive pressure at air inlet.

In the present embodiment, as shown in Fig. 2, Fig. 3 and Fig. 9, PCB automatic impedance-testing machines further include：The linear module of X-axis 60, the linear module 70 of Y-axis and z axis module 80, the linear module 60 of X-axis include two be oppositely arranged on test platform 20 X-axis slide rail 61, can reciprocating linear moves in two X-axis slide rails 61 installation pedestal 62 and the X that is arranged on test platform 20 Axis driving structure 63, X-axis driving structure drive the reciprocating linear in X-axis slide rail 61 of installation pedestal 62 to move；Installation pedestal 62 is wrapped The side plate 622 for including substrate 621 and being arranged along two edges of 621 length direction of substrate；The linear module 70 of Y-axis includes being arranged every Y-axis sliding rail 71 on a side plate 622, can reciprocating linear moves on two Y-axis sliding rails 71 sliding part 72 and mounted on installation Y-axis driving structure 73 on pedestal 62, Y-axis driving structure 73 drive the reciprocating linear on Y-axis sliding rail 71 of sliding part 72 to move；Z Axis module 80 include be oppositely arranged on two Z axis slide rails 81 on sliding part 72, can be reciprocal straight in two Z axis slide rails 81 The bearing 82 of line movement and the Z axis driving structure 83 being arranged on sliding part 72, Z axis driving structure 83 drive bearing 82 in Z axis Reciprocating linear drives on sliding rail 81, and measuring head 40 is mounted on bearing 82.Measuring head 40 can be linear in the linear module 60 of X-axis, Y-axis X is carried out under the action of module 70 and z axis module 80 respectively to, Y-direction and Z-direction movement, and then is treated in detection circuit board Measuring point is measured entirely.Installation pedestal and the linear module 70 of Y-axis are simple in structure, easy to process, at low cost；And two side plates are to base Plate plays booster action, increases the anti-bending strength of installation pedestal, improves load capacity, can effectively prevent in process Only installation pedestal is improved machining accuracy by pyrogenetic stress deformation.

In the present embodiment, as shown in figure 3, X-axis driving structure 63 includes X-axis motor 631, X-axis lead screw 632 and X-axis spiral shell Mother, X-axis motor 631 are arranged in one end of test platform 20；X-axis lead screw 632 extends along 20 length direction of test platform, X-axis silk One end of bar 632 and the output axis connection of X-axis motor 631, X-axis lead screw 632 are driven by X-axis motor 631 and are rotated, X-axis lead screw 632 both ends are separately installed with a connecting seat that X-axis lead screw 632 and test platform 20 are fixed；X-axis nut is arranged in X It is fixedly connected on axial filament bar 632 and with installation pedestal 62, X-axis nut is past along X-axis lead screw 632 under the rotation driving of X-axis lead screw 632 Complex line moves.

In the present embodiment, X-axis slide rail includes guide rail and the sliding block that is slidably disposed on guide rail, an installation pedestal 62 are fixedly connected with the sliding block on two guide rails, and under the driving of X-axis motor 631, the rotation of X-axis lead screw 632 drives X-axis nut to move It is dynamic, and then drive installation pedestal to move back and forth under the guiding role of guide rail and sliding block.

As Figure 9-Figure 11, side plate 622 is arranged perpendicular to substrate 621, and substrate 621 and two side plates 622 can be integrated Machine-shaping is the installation space of other assemblies between two side plates 622.Two Y-axis sliding rails 71 are arranged in two side plates 622 Top surface, the top surface of side plate 622 and the polished surface that the bottom surface of Y-axis sliding rail 71 is that a pair of matched is closed, the contact surface of strip are opposite It is all finished in the top surface of substrate 621, hence it is evident that the area for reducing finishing reduces because cutting fever causes Stress deformation.Y-axis sliding rail 71 can be fixed by the fasteners such as screw and side plate 622, the side that can also be coordinated by card slot Formula, which is realized, fixes.

In the present embodiment, Y-axis driving structure 73 includes：Y-axis motor 731, Y-axis lead screw 732 and Y-axis drive block 733, Y In 62 one end of installation pedestal, y-axis motor 731 is located in the installation space between two side plates 622 setting of spindle motor 731；Y-axis silk Bar 732 is set between both side plate 622 and extends along 62 length direction of installation pedestal, one end of Y-axis lead screw 732 and y-axis motor 731 output axis connection, Y-axis lead screw 732 are driven by y-axis motor 731 and are rotated, and the both ends of Y-axis lead screw 732 are separately installed with one The connecting seat 734 that Y-axis lead screw 732 and substrate 621 are fixed, connecting seat 734 are the fixed block of convex；Y-axis drive block 733 are arranged on Y-axis lead screw 732 and are moved along 732 reciprocating linear of Y-axis lead screw under the rotation driving of Y-axis lead screw 732.In this reality It applies in example, Y-axis drive block 733 is the feed screw nut being set on Y-axis lead screw 732, and Y-axis drive block 733 is fixed with sliding part 72 Setting.Specifically, the lower end of sliding part 72 forms a groove to match with 733 size of Y-axis drive block, Y-axis drive block 733 is solid Determine in a groove.

In the present embodiment, substrate 621 is being provided with boss 6211 with 734 corresponding position of connecting seat, and connecting seat 734 passes through Fixing piece or adhesive are fixedly mounted on boss 6211.Boss 6211 is that the corresponding portion of substrate 621 raises up to be formed, i.e., The height that the part is cut in machining is higher than other parts.The top surface of boss 6211 is polished surface.Lead screw is only in this way It is achieved that the fixation with substrate by two connecting seats and two boss, effectively reduces the area of installation pedestal finishing, Difficulty of processing is reduced, while reducing the stress deformation caused by cutting fever.

In the present embodiment, the both sides of sliding part 72 are equipped with the support arm 722 extended towards corresponding Y-axis sliding rail 71, that is, slide The longitudinal section of part 72 is downward opening concave character type.

In the present embodiment, Y-axis sliding rail 71 includes guide rail and the sliding block that is slidably disposed on guide rail, support arm 722 with Sliding block is fixedly connected, and under the driving of y-axis motor 731, the rotation of Y-axis lead screw 732 drives Y-axis drive block 733 to move, and then is leading Sliding part 72 is driven to move back and forth under the guiding role of rail and sliding block.

In the present embodiment, several holes 6212 are also formed on substrate 621, length of several holes 6212 along substrate 621 Spend directional spreding.The quality of installation pedestal can be mitigated and installation pedestal is made to be produced during process and later stage use Raw internal stress through hole release.In the present embodiment, several holes 6212 are located between two boss 6211, equidistantly set It sets.

Y-axis sliding rail, Y-axis lead screw, y-axis motor, Y-axis drive block and sliding part are detachably connected with installation pedestal, can be with It is assembled in test site, effectively prevents the damage caused by its precision in transportational process, improve the precision of complete machine. And y-axis motor is located between a pair of of Y-axis sliding rail, not will produce torque, load capacity is improved.

A mounting hole for installing Y-axis lead screw 732 is formed on connecting seat 734 in the present embodiment, mounting hole is along Y-axis The axial direction of lead screw 732 opens up, and is arranged in the center of connecting seat 734；The both ends of Y-axis lead screw 732 are respectively placed in two mounting holes, And it can be rotated in mounting hole under the driving of y-axis motor 731.The size of mounting hole is slightly larger than the diameter of Y-axis lead screw 732, protects Card Y-axis lead screw 732 can not only rotate inside it, but also will not fall off.

Above-mentioned sliding rail, motor, lead screw and nut constitutes Precision Lead-Screw guide track transmission mechanism, and Precision Lead-Screw guide rail passes Motivation structure reaches probe and carries out X, Y-direction movement in specified regional extent.

In the present embodiment, as shown in figure 9, being provided with square block 84 on sliding part 72, Z axis driving structure and Z axis slide rail are equal It is arranged in square block 84, Z axis driving structure includes Z axis motor, Z axis lead screw and Z axis nut, and Z axis motor is arranged in square block 84 Top；Z axis lead screw extends along Z-direction, and one end of Z axis lead screw and the output axis connection of Z axis motor, Z axis lead screw are driven by Z axis motor And rotate, the both ends of Z axis lead screw are separately installed with a connecting seat that Z axis lead screw and square block are fixed；The setting of Z axis nut exists It is fixedly connected on Z axis lead screw and with bearing 82, Z axis nut is moved along Z axis lead screw reciprocating linear under the rotation driving of Z axis lead screw.

In the present embodiment, Z axis slide rail includes guide rail and the sliding block that is slidably disposed on guide rail, and bearing is solid with sliding block Fixed connection, under the driving of Z axis motor, the rotation of Z axis lead screw drives the movement of Z axis nut, and then makees in the guiding of guide rail and sliding block It is moved back and forth with lower drive bearing.

In the present embodiment, square block is equipped with detection locating module 95, and detection locating module 95 is for detecting positioning circuit The position of plate and position for detection test points.Specifically, detection locating module is CCD industrial cameras.

In the present embodiment, including installation pedestal 62 and all components thereon form left mould block, are additionally provided in X-axis slide rail Right mould block identical with left mould block structure, left mould block and right mould block are oppositely arranged, and at this moment installation pedestal is two, X-axis driving knot Structure is also two, and an X-axis driving structure drives an installation pedestal, and two X-axis driving structures are close to the edge of test platform Setting is convenient for reserving larger test zone in this way.Left mould block and right mould block can treat the measuring point in detection circuit board simultaneously It measures, effectively improves testing efficiency.

In the present embodiment, as shown in Figure 12-Figure 15, measuring head 40 is including rotating disk 41 and in rotating disk 41 Probe switching device, bearing 82 are equipped with the rotational structure 51 being drivingly connected with rotating disk 41, and probe switching device includes：Support Body 42, the first probe portion and at least two second probe portions, the first probe portion are movably arranged with respect to supporter 42, the first probe Portion have at least two first test positions, the first probe portion can between at least two first test positions mobile handoff；Often A second probe portion is movably arranged with respect to supporter 42, and each second probe portion has the second inspection coordinated with the first probe portion The evacuation position in the first probe portion and the cooperation of remaining second probe portion is set and avoided to location, and the second probe portion can be in the second detection Mobile handoff between position and evacuation position.

Using the probe switching device of the present embodiment, the first probe locations at least two first test positions first When a first test position, the first probe portion is examined with first the second probe portion cooperation at least two second probe portions It surveys, remaining second probe portion is in evacuation position；After having detected, the first probe portion is moved to second the first check bit It sets, the second probe portion is detected with second the second probe portion cooperation, remaining second probe portion is in evacuation position；First The detection process of probe portion other positions is same as described above, is no longer described in detail herein.Above structure need not dismantle probe portion, It only needs to move back and forth the first probe portion and the second probe portion, so that it may it is effective to improve test effect to realize switching, into And it avoids due to frequently replacing probe there is a situation where wearing to cause measuring accuracy low, to improve measuring accuracy.Also, it is above-mentioned Structure the case where avoiding using multipair probe in the prior art, and then can reduce probe using a corresponding multiple form Number so that visit testing cost substantially reduce.

In the present embodiment, rotational structure 51 is motor, and the output shaft of motor is connect with rotating disk 41.

In the present embodiment, probe switching device further includes for being arranged on supporter 42 and being connect with the first probe portion One driving mechanism 43, the first driving mechanism 43 drive the first probe portion to be switched between at least two first test positions. The movement of the first probe portion, realization is driven to automatically control and switch by the first driving mechanism 43 so that testing efficiency and precision are big It is big to improve.First driving mechanism 43 drives the first probe portion to move linearly in the horizontal direction, multiple check bits in the first probe portion It is simple in structure setting on straight line, it is easy to remove.

In the present embodiment, probe switching device further includes being connected between the first driving mechanism 43 and the first probe portion Interconnecting piece 47, the first driving mechanism 43 drive the first probe portion to move by the way that drive connection portion 47 is mobile in the horizontal direction.Connection Portion 47 plays the role of connecting the first driving mechanism 43 and the first probe portion, and connection is easy.Certainly, the first driving mechanism 43 also may be used Directly to be connect with the first probe portion.

In the present embodiment, the first driving mechanism 43 is linear motor, and interconnecting piece 47 is fixed on the output end of linear motor On.Probe can carry out stepless switching by motor, greatly improve measuring accuracy.Certainly, the first driving mechanism 43 also may be used With using structures such as cylinder, hydraulic cylinder, rack-and-pinion, worm and gears, when the first driving mechanism 43 is cylinder, interconnecting piece is fixed on On the piston rod of cylinder.It is appreciated that in other embodiments, the first driving mechanism 43 can also include motor and ball wire Thick stick, the output shaft of motor and the screw rod of ball-screw connect, and interconnecting piece is fixed on the nut of ball-screw.

In the present embodiment, as shown in Figure 15 and Figure 18, the first driving mechanism 43 is fixed on the upper surface of supporter 42, even One end of socket part 47 is connect with the first driving mechanism 43, and the other end of interconnecting piece 47 passes through supporter 42 and is located at supporter 42 First probe portion of lower section connects.Structure, characteristics of compact layout can be simplified in this way.Specifically, interconnecting piece is link block.

In the present embodiment, the first probe portion includes the first probe base 441 and the first probe 442, and the first probe base 441 is solid It is scheduled on interconnecting piece 47, the first probe 442 is mounted on the first probe base 441.

In the present embodiment, probe switching device further includes the second driving mechanism being connect with each second probe portion, the Two driving mechanisms drive each second probe portion to be switched between the second test position and evacuation position.Pass through the second driving Mechanism drives the movement of the second probe portion, realization to automatically control and switch, effective to improve testing efficiency and precision.

In the present embodiment, the second driving mechanism drives the second probe portion vertically to move, and evacuation position is higher than the Two test positions and the first test position.It is simple in structure, it is easy to remove.Specifically, the second driving mechanism is to be fixed on interconnecting piece Switching part 46 on 47, switching part 46 has climbing structure, and in the moving process of switching part 46, climbing structure jacks up second and visits Needle portion is so that the second probe portion switches to evacuation position from the second test position.Linear motor can both drive the first probe portion to cut Change place can also drive the second probe portion switching position, the movement in the first probe portion and the movement in the second probe portion total simultaneously With a motor, simplifies the overall structure of probe switching device, substantially reduce cost.

In the present embodiment, the number in the second probe portion is two, and two the second probe portions are not matched with the first probe portion It closes to test two kinds of different data.Since error of measurement timesharing needs two probes all connecting cables, when surveying single-ended in two probes only High frequency cable therefore is connected in a second probe portion and the first probe portion there are one probe connecting cable, another second spy It is not connected to cable in needle portion, oneself between two the second probe portions is then realized by motor driving the first probe portion movement Dynamic switching, and then realize the switching for surveying single-ended and difference.

As shown in Figure 16 and Figure 17, there are two be obliquely installed and its inclined direction phase the tool of switching part 46 relative to vertical direction Anti- inclined-plane 461 and the plane 462 being connected between two inclined-planes 461, two inclined-planes 461 form climbing structures and respectively with two Cooperation inclined-plane cooperation on the voussoir 454 in a second probe portion.When on the voussoir 454 and switching part 46 in a second probe portion When one inclined-plane cooperation, voussoir 454 and the plane on switching part 46 in another the second probe portion coordinate, and are moved in switching part 46 During, the voussoir 454 in a second probe portion is slided to from an inclined-plane from plane, the voussoir in another the second probe portion 454 from another inclined-plane that plane slides to switching part 46.The automatic of probe can be realized by switching part 46 and voussoir cooperation Switching, it is simple in structure, it is easy to operate.Certainly, switching part may be set to be such as lower structure：Switching part has spaced two Two inclined-planes of a plane and connection between two planes, two inclined-planes are obliquely installed relative to vertical direction and its inclination side To on the contrary, the structure of switching part is also not limited to this.

Specifically, switching part 46 is switch boards, and switch boards include two inclined plates being oppositely arranged and are connected to two inclined plates Between tablet, two inclined plates are upwardly and outwardly obliquely installed relative to the center line of tablet.Certainly, the cooperation of switch boards and voussoir Mode can also be substituted by other mechanisms such as cam, connecting rod.

In the present embodiment, as shown in figure 15, probe switching device further includes a pair of at least two second probe portion one At least two mounting brackets 48 answered, mounting bracket 48 are relatively fixed setting with supporter 42, and the second probe portion can be relative to peace Dress holder 48 is movably disposed.The setting of mounting bracket 48 can be in order to simplify the structure of supporter, while also allow for installing Second probe portion.Specifically, mounting bracket 48 is L-shaped.

In the present embodiment, as shown in Figure 15 to Figure 17, the second probe portion includes the second probe base 451, the second probe 452, guide rod 453 and voussoir 454, the second probe 452 and guide rod 453 are each attached on the second probe base 451, mounting bracket 48 there is the pilot hole coordinated with guide rod 453, switching part 46 to have the slot hole 463 worn for guide rod 453, slot hole 463 Moving direction along switching part 46 extends, and guide rod 453 sequentially passes through pilot hole and slot hole far from 451 one end of the second probe base Voussoir 454 is equipped with after 463, voussoir 454 is supported on the outside of slot hole 463.Guide rod is vertically arranged, and guide rod coordinates with pilot hole Play the role of guiding.During switching part moves horizontally, guide rod changes in the position of slot hole.

In the present embodiment, the second probe portion further includes applying pressure so that the second probe base 451 to the second probe base 451 The return unit 455 of reset.Return unit 455 can ensure that the second probe portion is in the stability of test position, ensure measuring accuracy. Specifically, return unit 455 is to be sleeved on guide rod 453 and the spring between the second probe base 451 and mounting bracket 48. Spring is easy to use, of low cost.During measurement, system can automatic monitoring probe move distance, probe is downward Move distance it is bigger, probe is bigger to the pressure of measuring point, reasonably selects the parameter of spring, and the stringent probe that controls is to measuring point Pressure reduces the speed of probe downlink, can be to avoid damage measuring point.It is of course also possible to use other elastic devices replace spring.

In the present embodiment, supporter 42 is support disk, and disc structure is simple, also allows for other portions such as installation motor Part.Specifically, mounting bracket 48 is mounted on the lower surface of supporter 42.

In the present embodiment, the second probe is equipped with short-contact metal piece, when test the second probe by short-contact metal piece with First probe short circuit.Short-contact metal piece is preferably short circuit copper sheet.

In the present embodiment, probe switching device further includes the displacement sensing of the moving displacement for detecting the first probe portion Device 49, between the first driving mechanism 43 is adjusted between one in the first probe portion and at least two second probe portions when detecting Away to detect the data of different spacing.It is drivingly connected block movement by motor, and then drives the movement of the first probe 442, first When probe 442 and first the second probe cooperation are detected, motor adjusts the spacing between the first probe and first probe, Displacement sensor can detect the moving displacement of the first probe 442, and then test the data of different spacing, and difference is surveyed to realize Without needing to change probe when the data of spacing.Specifically, displacement sensor 49 is laser sensor.It is of course also possible to use other Displacement sensor replaces laser sensor.

As shown in Figure 13 and Figure 14, rotating disk 41 is supported on by multiple pillars on support disk, and displacement sensor 49 is solid It is scheduled on the lower surface of rotating disk 41, motor and part link block are located between support disk and rotating disk.

The CCD industrial camera modules positioned at the side of measuring head are additionally provided on bearing, CCD industrial cameras module can obtain Take the point position on pcb board.

Probe unit is substantially using manual or fixed probe spacing test mode, manual test in the prior art When, pressure difference of the probe every time on pcb board so that test result is unstable, measuring accuracy is low, poor repeatability, testing efficiency Lowly；When using fixed probe spacing test, since probe spacing is fixed, when pcb board impedance for surveying different spacing, needs replacing Probe so that testing efficiency can not improve, and the probe due to needing to make largely different spacing, greatly improve impedance survey The cost of examination.Therefore, compared with prior art in manual test or the test of fixed probe spacing, the probe switching of the utility model Device can test the PCB impedances (containing difference and single-ended) of arbitrary spacing, realize stepless speed changing adjustment, obviously has the following advantages： 1, high degree of automation, without carrying out probe replacement according to different probe spacing, directly by devices such as motors when extremely short The interior adjustment for completing the spacing between two probes；2, the stepless changing of the spacing between two probes, can no longer make The probe groups of different spacing can save a large amount of side view cost due to the higher price of probe groups；3, pass through PLC or software The fine adjustment of spacing between control probe can greatly improve the accuracy and measuring accuracy of test；4, due to automation Degree is high, can greatly promote the reliability, repeatability and testing efficiency of test result.

The course of work of the probe switching device in the present embodiment is illustrated below in conjunction with Figure 15 to Figure 17, for just In description, replaces the first probe and probe A with probe B and probe C replaces two the second probes and is described, motor is drivingly connected Block moves, and switch boards and link block move together so that probe B is close to probe A or probe C.When probe B is close to probe A, by It is contacted in the lower plane of the effect voussoir of spring and with the upper horizontal plane of switch boards, makes the needle point of probe A and probe B in same water In plane, simultaneously because the effect on the inclined-plane of switch boards moves up probe C by voussoir so that the needle point of probe C is higher than The horizontal plane of probe A and probe B can carry out pcb board testing impedance with probe A and probe B at this time, adjust probe A and probe B Between spacing, test the data of different spacing.Conversely, when probe B is close to probe C, can be carried out with probe B and probe C Pcb board testing impedance adjusts the spacing between probe B and probe C, tests the data of different spacing.In this way, being achieved that probe The automatic stepless of testing impedance switches so that testing efficiency greatly improves, and without preparing multigroup probe groups so that probe is surveyed Examination cost substantially reduces.

In the present embodiment, as shown in Fig. 3 and Figure 19, test platform 20, which is equipped with, is located at 100 side of circuit board to be detected Calibration module, test platform 20 is equipped with the avoid holes of evacuation calibration module, and calibration module includes positioning calibration assemblies and resistance Anti- calibration assemblies, positioning calibration assemblies include：Mounting plate 91, glass calibration plate 92 and camera 93, mounting plate 91 have first Avoid holes；Glass calibration plate 92 is mounted on the top of mounting plate 91 and, glass calibration plate 92 corresponding with the position of the first avoid holes It is equipped with the groove face for calibrating probe location；The position in the lower section of mounting plate 91 and the first avoid holes is arranged in camera 93 It is corresponding.Camera 93 is CCD industrial cameras.When calibration, three probes are moved to the top of glass calibration plate 92, pass through CCD Industrial camera can see the position of three probes clearly, then adjust the position of one of probe, can be to the position between two probes It sets and is calibrated.

In the present embodiment, as shown in figure 20, glass calibration plate 92 is glass linear scale, the graduation mark on glass linear scale It is vertically arranged including a plurality of horizontal groove disposed in parallel and with every horizontal groove and a plurality of perpendicular groove disposed in parallel.

In the present embodiment, also there are mounting plate 91 second avoid holes, impedance correction plate 94 to be mounted on the top of mounting plate And it is corresponding with the position of the second avoid holes, mounting plate 91 and impedance correction plate 94 form impedance calibration component, that is, position calibration group Part and impedance calibration component share a mounting plate, and impedance correction plate 94 is equipped with multipair test point, for measuring practical impedance Value, according to real impedance values compensatory theory impedance value, can eliminate the systematic error of measurement so that impedance measurement has good survey Accuracy of measurement.

In the present embodiment, PCB automatic impedance-testings machine further includes support base 10, and the setting of test platform 20 is at support bottom On seat 10.Support base 10 be applied not only to support test platform and all components on test platform or electric controling element, The mounting table of motor driver, cable wire casing.Electric controling element can be used for controlling opening for PCB automatic impedance-testing machines Dynamic, stopping resets, the display of three color status lamps.Test platform 20 is marble.Certainly, the material of test platform is also and unlimited In this.Display frame holder is additionally provided in support base 10, display bracket is equipped with display and keyboard, and display and keyboard are The operation interface of equipment normal work.

In the present embodiment, supporting rack 130 is additionally provided on test platform 20, supporting rack 130 is equipped with oscillograph 110, shows The wavy curve that unlike signal changes over time can be shown on wave device.Oscillograph 110 is located at the top of left mould block and right mould block. Outer casing framework 120 is additionally provided on test platform 20, outer casing framework 120 is used to support the shell being located at outside outer casing framework.

In the present embodiment, PCB automatic impedance-testings machine further includes test instrumentation, and TDR measurements may be used in test instrumentation Instrument or VNA vector network analyzers.Certainly, test instrumentation, which may be other, can measure the instrument of impedance.

The course of work of PCB automatic impedance-testing machines is briefly described below, and the single-ended or difference measuring point in pcb board is in PCB There are fixed relative position and a relative angle in inside, CCD industrial cameras obtain measuring point position and angle information after by measuring point Information is sent to motion-control module, by the small X of moving control module for controlling probe, the movement of Y-axis, angle adjustment amount and Away from adjustment etc..After the completion of adjustment, then probe downlink controlled by PLC, probe stops after touching the measuring point of pcb board.Then it is System issues commands to test instrumentation, and control test instrumentation measures impedance, obtains the impedance curve of measurement and corresponding impedance measurement Data.Operation is finished up to all measuring points in pcb board all measure repeatedly, and the full-automatic of PCB impedances has been achieved It measures, measurement efficiency greatly improves.PCB automatic impedance-testings machine can also be precisely controlled pressure, to point position into Row is accurately positioned so that the consistency of impedance measurement is fine.

It can be seen from the above, PCB automatic impedance-testing equipments have the advantage that：1, accurately pressure controls, and protects measuring point Pad；2, very high positioning accuracy is suitable for the impedance measurement of various pcb boards；3, fixed form is adsorbed, soft board, hardboard all may be used With fixation；4, impedance measurement precision is high, and the consistency of measurement is fine；5, system automatic adjusting position and angle, testing efficiency are high.

Obviously, the above embodiments are merely examples for clarifying the description, and does not limit the embodiments.It is right For those of ordinary skill in the art, can also make on the basis of the above description it is other it is various forms of variation or It changes.There is no necessity and possibility to exhaust all the enbodiments.And it is extended from this it is obvious variation or Among the protection domain that variation is created still in the utility model.

Claims (20)

1. a kind of PCB automatic impedance-testings machine, including：

Test platform (20)；

Substrate absorption device (30), be arranged on the test platform (20), the substrate absorption device (30) include from down toward It is upper to be stacked the bottom plate (31) being arranged and panel (33), it is provided with air inlet (312), the air inlet on the bottom plate (31) (312) side on is connected with negative pressure source, and several through-holes (332) are provided on the panel (33), are put on the panel (33) It is equipped with circuit board to be detected (100)；

Measuring head (40) is movably disposed on the test platform (20) and is carried out to the circuit board (100) to be detected Detection；

It is characterized in that, the substrate absorption device (30) further includes being arranged between the bottom plate (31) and the panel (33) Flow distribution plate (32), the air-flow on the flow distribution plate (32) on the region of the air inlet (312) is less than institute by area It states the air-flow on flow distribution plate (32) on the region far from the air inlet (312) and passes through area.

2. PCB automatic impedance-testings machine according to claim 1, which is characterized in that be provided on the flow distribution plate (32) Equal stomata (321), stomata (321) aperture far from the air inlet (312) are not more than close to the air inlet (312) in aperture Stomata (321) aperture.

3. PCB automatic impedance-testings machine according to claim 2, which is characterized in that the stomata (321) is with the air inlet It is rectangular centered on mouthful (312) that external diffusion, the aperture of the stomata (321) on the same rectangle is equal, each rectangle it Between equidistantly distributed.

4. PCB automatic impedance-testings machine according to claim 2, which is characterized in that described on the flow distribution plate (32) Stomata (321) is centered on the air inlet (312) in a spoke shape distribution.

5. PCB automatic impedance-testings machine according to claim 4, which is characterized in that the stomata on each spoke straight line (321) spacing is that starting point is distributed in arithmetic progression with air inlet (312), and stomata (321) aperture on each spoke straight line is equal It is that starting point is distributed in Geometric Sequence with air inlet (312).

6. PCB automatic impedance-testings machine according to claim 2, which is characterized in that far from institute on the flow distribution plate (32) It states stomata (321) gap on the region of air inlet (312) and is less than the stomata on the region of the air inlet (312) (321) gap.

7. PCB automatic impedance-testings machine according to claim 1, which is characterized in that be provided on the flow distribution plate (32) The equal stomata in aperture (321), between the stomata (321) on the flow distribution plate (32) on the region far from the air inlet (312) Gap is less than stomata (321) gap on the region of the air inlet (312).

8. PCB automatic impedance-testings machine according to claim 1, which is characterized in that the PCB automatic impedance-testings machine is also Including：

The linear module of X-axis (60), including be oppositely arranged on the test platform (20) two X-axis slide rails (61), can be two The installation pedestal (62) that reciprocating linear moves on a X-axis slide rail (61) and the X-axis being arranged on the test platform (20) Driving structure (63), the X-axis driving structure (63) drive the installation pedestal (62) reciprocal straight in the X-axis slide rail (61) Line moves；The installation pedestal (62) includes substrate (621) and is arranged along two edges of the substrate (621) length direction Side plate (622)；

The linear module of Y-axis (70), including Y-axis sliding rail (71) on each side plate (622) is set, can be in two Y The sliding part (72) and the Y-axis driving structure in the installation pedestal (62) that reciprocating linear moves on axis sliding rail (71) (73), the Y-axis driving structure (73) drives the sliding part (72) reciprocating linear on the Y-axis sliding rail (71) to move；

Z axis module (80), including be oppositely arranged on the sliding part (72) two Z axis slide rails (81), can be at two The bearing (82) and the Z axis driving structure being arranged on the sliding part (72) that reciprocating linear moves on the Z axis slide rail (81) (83), the Z axis driving structure (83) drives the bearing (82) reciprocating linear in the Z axis slide rail (81) to drive, described Measuring head (40) is mounted on the bearing (82).

9. PCB automatic impedance-testings machine according to claim 8, which is characterized in that the top surface of the side plate (622) and institute The bottom surface for stating Y-axis sliding rail (71) is the polished surface that a pair of matched is closed.

10. PCB automatic impedance-testing machines according to claim 8 or claim 9, which is characterized in that the Y-axis driving structure (73) Including：

Y-axis motor (731) is arranged in the installation pedestal (62) one end；

Y-axis lead screw (732) is set between two side plates (622) and extends along the installation pedestal (62) length direction, The Y-axis lead screw (732) is driven by the y-axis motor (731) and is rotated, and the both ends of the Y-axis lead screw (732) are separately installed with One connecting seat that the Y-axis lead screw (732) and the substrate (621) are fixed；

Y-axis drive block (733) is arranged on the Y-axis lead screw (732) and rotates driving lower edge institute in the Y-axis lead screw (732) The movement of Y-axis lead screw (732) reciprocating linear is stated, the Y-axis drive block (733) is fixedly installed with the sliding part (72).

11. PCB automatic impedance-testings machine according to claim 8, which is characterized in that the measuring head (40) includes rotation Disk (41) and the probe switching device in the rotating disk (41), the bearing (82) are equipped with and the rotating disk (41) rotational structure (51) being drivingly connected, the probe switching device include：

Supporter (42)；

First probe portion, the relatively described supporter (42) are movably arranged, and first probe portion has at least two first inspections Location is set, first probe portion can between described at least two first test positions mobile handoff；

At least two second probe portions, the relatively described supporter (42) are movably arranged, each second probe portion have with it is described Second test position of the first probe portion cooperation and evacuation first probe portion and the cooperation of remaining second probe portion Avoid position, second probe portion can between second test position and the evacuation position mobile handoff.

12. PCB automatic impedance-testings machine according to claim 11, which is characterized in that the probe switching device is also wrapped Include the first driving mechanism (43) for being arranged on the supporter (42) and being connect with first probe portion, first driving Driving first probe portion of mechanism (43) switches between at least two first test positions.

13. PCB automatic impedance-testings machine according to claim 12, which is characterized in that the probe switching device is also wrapped Include the interconnecting piece being connected between first driving mechanism (43) and first probe portion, first driving mechanism (43) By driving the interconnecting piece is mobile in the horizontal direction to drive the movement of first probe portion.

14. PCB automatic impedance-testings machine according to claim 13, which is characterized in that the probe switching device is also wrapped Include the second driving mechanism being connect with each second probe portion, each second probe of the second driving mechanism driving Portion switches between second test position and the evacuation position.

15. PCB automatic impedance-testings machine according to claim 14, which is characterized in that the second driving mechanism driving Second probe portion vertically moves, and the evacuation position is higher than second test position and first check bit It sets.

16. PCB automatic impedance-testings machine according to claim 15, which is characterized in that second driving mechanism is solid The switching part (46) being scheduled on the interconnecting piece, the switching part (46) have climbing structure, the shifting in the switching part (46) During dynamic, the climbing structure jacks up second probe portion so that second probe portion is cut from second test position Shift to the evacuation position.

17. PCB automatic impedance-testings machine according to claim 16, which is characterized in that the switching part (46) has two It is a to be obliquely installed relative to vertical direction and inclined-plane (461) that its inclined direction is opposite and be connected to two inclined-planes (461) Between plane (462), two inclined-planes (461) formed the climbing structure and respectively with two second probe portions Cooperation inclined-plane cooperation on voussoir.

18. PCB automatic impedance-testings machine according to claim 1, which is characterized in that the test platform (20) is equipped with Positioning calibration assemblies positioned at circuit board (100) side to be detected, the positioning calibration assemblies include：

Mounting plate (91) has the first avoid holes；

Glass calibration plate (92) is mounted on the top of the mounting plate (91) and, institute corresponding with the position of the first avoid holes Glass calibration plate (92) is stated equipped with the groove face for calibrating probe location；

Camera (93), setting is in the lower section of the mounting plate (91) and the position of first avoid holes correspondence.

19. PCB automatic impedance-testings machine according to claim 1, which is characterized in that the test platform (20) is equipped with Impedance correction plate (94) positioned at circuit board (100) side to be detected, the impedance correction plate (94) are equipped with multipair survey Pilot, for measuring real impedance values.

20. PCB automatic impedance-testings machine according to claim 1, which is characterized in that the PCB automatic impedance-testings machine Further include support base (10), the test platform (20) is arranged in the support base (10).