A self-adjusting flying probe module for four-terminal testing

Abstract

The present invention relates to the technical field of flying probe modules, and specifically to a self-adjusting flying probe module for four-terminal testing. The self-adjusting flying probe module is arranged on a flying probe machine, and the self-adjusting flying probe module includes: two elastic tool holders, which are installed and connected to the flying probe machine through needle seats; detection blades, which are arranged at one end of the tool holder and are used for four-terminal testing of a PCB board; a self-adjusting component, which is connected to the tool holder and is arranged on the detection blade and is used for adjusting the tip position of the detection blade. The flying probe module of the present invention adopts an independent double-blade design for four-wire method testing of the PCB board. The self-balancing component designed based on the principle of the balance lever automatically adjusts the tips of the double blades, reducing the error of the tips. The double blades are insulated from each other, and no short-circuit phenomenon will occur. The detection process is stable and reliable, the circuit board will not be damaged, and the detection accuracy is high.

Description

Technical Field

[0001] The present invention relates to the technical field of flying probe modules, and specifically to a self-adjusting flying probe module for four-terminal testing. Background Art

[0002] A flying probe tester tests a PCB board with high density, many layers, large wiring density, and small measuring point distance through a flying probe module, mainly testing the insulation and conduction values of the circuit board.

[0003] In the prior art, the invention creation with the application number: CN201420106716.5, named flying probe tester and its flying probe test shaft, is disclosed. It tests by contacting a single test probe with the PCB board, with poor test accuracy and is not suitable for testing high-precision and high-density PCB boards produced currently.

[0004] In the prior art, the four-wire method is used to test the circuit board to improve the test accuracy. However, in the prior art, a single detection probe such as that in the application number: CN201420106716.5 is not suitable for high-precision detection, has large errors, and is easy to scratch the circuit board, resulting in poor conditions such as copper adhesion shedding, needle marks, and scratches after detection. Summary of the Invention

[0005] The purpose of the present invention is to provide a self-adjusting flying probe module for four-terminal testing to solve the problems in the prior art.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A self-adjusting flying probe module for four-terminal testing, the self-adjusting flying probe module is arranged on a flying probe machine, and the self-adjusting flying probe module includes:

[0008] Two elastic tool holders, and the tool holders are installed and connected to the flying probe machine through needle seats.

[0009] Detection blades, which are arranged at one end of the tool holder and are used for four-terminal testing of the PCB board.

[0010] A self-adjusting component, which is connected to the tool holder and is arranged on the detection blade for adjusting the tip position of the detection blade.

[0011] Further, an installation groove is provided on the needle seat, a first threaded hole is arranged in the installation groove, a pre-pressure tension pin is installed in the installation groove for providing pre-pressure to the tool holder, a connecting plate is installed on the needle seat, and an adjustable reflective photoelectric switch is installed on the needle seat for monitoring the change of the pressure value of the flying probe module during the test process.

[0012] Further, the tool rest includes a connecting column, a first elastic frame and a second elastic frame. The first elastic frame is a rectangular structure composed of a fixed rod, a first connecting rod and two first rocker arms. The two first rocker arms are connected and arranged between the fixed rod and the first connecting rod.

[0013] One end of the first elastic frame is provided with a mounting hole. One end of the second elastic frame is fixedly provided with a second connecting rod, and a jack is opened on the second connecting rod.

[0014] Further, the second elastic frame is a rectangular structure composed of a first connecting rod, a second connecting rod and two second rocker arms. The tool rest is made of PBT material. The thicknesses at both ends of the second connecting rod are thinner than the remaining positions, forming elastic pieces. A tool groove is arranged on one side of the second connecting rod for installing a detection blade.

[0015] Further, the first elastic frame is provided with connection holes distributed in an array. A connection block is arranged inside the first elastic frame. A bolt passes through a through hole on the connection block and is connected to a first threaded hole. One side of the tool rest is provided with a grinding surface, and the grinding surfaces of two tool rests are attached and connected.

[0016] The two tool rests are connected and fixed through the cooperation of the connecting column and the connection hole.

[0017] Further, the detection blade includes a first blade and a second blade. An insulating sheet is arranged between the first blade and the second blade. The insulating sheet is connected and fixed to the jack through an insulating column, so that the insulating sheet is installed between the first blade and the second blade.

[0018] Further, the self-adjusting component is arranged on the second elastic frame. The self-adjusting component includes a triangular frame, a rotating blade and a rotating rod. One end of the triangular frame is connected to the mounting holes on two tool rests through two connecting columns, and a fixing groove is opened at the other end. The rotating blade is rotatably connected to the rotating rod through a rotating hole arranged in the middle thereof. The rotating rod passes through the rotating hole and is tightly connected to the fixing groove.

[0019] Further, the second elastic frame is provided with a fixing hole, and an adjusting rod is installed on the fixing hole. The upper end of the adjusting rod is attached to both ends of the rotating blade, and the first blade and the second blade are adjusted through the principle of the balance lever.

[0020] The beneficial effects of the present invention:

[0021] 1. The flying needle module of the present invention adopts an independent double-blade design for four-wire method testing of the PCB board. The self-balancing component designed based on the principle of the balance lever automatically adjusts the tips of the double blades, reducing the error of the tips. The insulation treatment between the double blades prevents short-circuit phenomena. The detection process is stable and reliable, does not damage the circuit board, and has high detection accuracy;

[0022] 2. The flying probe module of the present invention can move in the X, Y, and Z axes for PCB board detection. The tool holder is made of PBT material, with excellent performance and elasticity, providing support for the high-precision detection of the flying probe module. The deformation of the tool holder is reliable, the detection result is accurate, and the blade is installed and fixed stably. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below with reference to the accompanying drawings.

[0024] Figure 1 is an exploded structural schematic diagram of the flying probe module of the present invention

[0025] Figure 2 Partial structural schematic diagram of the flying probe machine of the present invention;

[0026] Figure 3 is the present invention Figure 2 Enlarged structural schematic diagram at A in;

[0027] Figure 4 is the structural schematic diagram of the needle seat of the present invention;

[0028] Figure 5 is the structural schematic diagram of the needle seat and the flying probe module of the present invention;

[0029] Figure 6 is an exploded structural schematic diagram of the flying probe module of the present invention;

[0030] Figure 7 is the structural schematic diagram of the tool holder of the present invention;

[0031] Figure 8 is the adjustment schematic diagram of the flying probe module of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0032] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0033] A self-adjusting flying probe module for four-terminal testing, such as Figure 2 , Figure 3As shown in the figure, the self-adjusting flying probe module is arranged on the needle base 2. A connecting plate 20 is installed on the needle base 2. The connecting plate 20 is connected and installed on the moving plate 5. There are 8 moving modules 6 on the flying probe machine. The moving module 6 is installed on the electric slide table on the flying probe machine and is used to drive the moving module 6 to move on the X-axis and Y-axis. There is also an electric slide table on the moving module 6, which is used to drive the moving plate 5 to move along the X-axis direction on the moving module 6. A Z-axis belt is also arranged on the moving plate 5, which is used to drive the connecting plate 20 to reciprocate along the Z-axis direction, so as to realize the four-wire method test on the PCB board.

[0034] As Figure 4 shown in the figure, an installation groove 24 is opened on the needle base 2. A cushion block 21 is fixedly arranged in the installation groove 24. A first threaded hole 22 is arranged on the cushion block 21. A pre-tightening tension pin 23 is installed in the installation groove 24. A groove 25 is arranged on one side of the installation groove 24. A second threaded hole 26 is arranged on the needle base 2.

[0035] As Figure 5 shown in the figure, the connecting plate 20 is installed on the needle base 2 through bolts. The bolts pass through the connecting plate 20 and are tightly connected with the second threaded hole 26. An adjustable reflective photoelectric switch ITR8307 is installed in the groove 25. When a detected object passes by, the object reflects the signal emitted by the photoelectric switch transmitting end to the receiving end, so the photoelectric switch generates a switching action, and the change of the pressure value during the test of the flying probe module is grasped in real time, so as to realize the high-speed and precision test of the flying probe tester.

[0036] As Figure 1 、 Figure 6 、 Figure 7 shown in the figure, the self-adjusting flying probe module includes two tool holders. One end of the tool holder is provided with a first blade 3 and a second blade 4. The first blade 3 and the second blade 4 are symmetrically arranged at one end of the tool holder. A self-adjusting component is arranged on the tool holder, and the self-adjusting component is used to adjust the tip positions of the first blade 3 and the second blade 4. An insulating sheet 19 is arranged between the first blade 3 and the second blade 4 to block the first blade 3 and the second blade 4.

[0037] The tool holder includes a first elastic frame 12 and a second elastic frame 18. Both the first elastic frame 12 and the second elastic frame 18 are rectangular structures. One end of the first elastic frame 12 is connected to the second elastic frame 18. The first elastic frame 12 is provided with connection holes 11 distributed in an array. A connection block 10 is arranged in the first elastic frame 12. The connection block 10 is provided with a through hole 101 and a connection hole 11. The bolt passes through the through hole 101 and cooperates with the first threaded hole 22.

[0038] The tool rest is made of PBT material, which has high strength, fatigue resistance, dimensional stability, and low creep; good heat aging resistance; solvent resistance; water stability; excellent insulation performance; dielectric constant: 3.0 - 3.2; arc resistance; can be injection-molded or extruded by ordinary equipment, with fast processing and molding; the tool rest with a two-stage square elastic frame structure enables the flying probe module to have a more sensitive test effect.

[0039] One side of the tool rest is provided with a grinding surface 121. After being ground by a grindstone, the burrs and flash formed during the molding process of the injection-molded part support are eliminated. The grinding surfaces 121 of the two tool rests are fitted together and connected and fixed through the connecting column 14 and the connecting hole 11 to stably connect the two tool rests.

[0040] One end of the first elastic frame 12 is provided with a mounting hole 122. The second elastic frame 18 is provided with a fixing hole 17. An adjusting rod 15 is installed on the fixing hole 17. One end of the second elastic frame 18 is fixedly provided with a second connecting rod 184. A jack 181 is opened on the second connecting rod 184. An insulating column 191 is fixedly provided in the jack 181. The insulating sheet 19 is installed between the two tool rests through two insulating columns 119.

[0041] The first elastic frame 12 includes a fixed rod 126, a first connecting rod 125, and two first rocker arms 124. The two first rocker arms 124 are arranged between the fixed rod 126 and the first connecting rod 125 to form the first elastic frame 12 similar to a double rocker mechanism. The first rocker arm 124 can swing on the fixed rod 126. The second connecting rod 184 is arranged at one end of the second elastic frame 18 away from the first elastic frame 12. A tool slot 16 is arranged on one side of the second connecting rod 184 for fixedly installing the first blade 3 or the second blade 4.

[0042] The second elastic frame 18 includes a first connecting rod 125, a second connecting rod 184, and two second rocker arms 182. The two ends of the second connecting rod 184 are thinned, and elastic pieces are formed by using the high toughness of the PBT material, so that the second rocker arm 182 can swing around the connection between the first connecting rod 125 and the second rocker arm 182. The first rocker arm 124 and the second rocker arm 182 have the same structure.

[0043] During the actual test process, the second elastic frame 18 first undergoes primary deformation, then the first elastic frame 12 starts secondary elastic deformation, and finally the secondary deformation amount is captured by the photoelectric sensor and used as the feed amount of the flying probe tester in the Z-axis direction when hitting the PCB board.

[0044] The installation position of the insulating column 191 not only realizes the positioning and installation of the insulating sheet 19, but also limits the movement range of the second elastic frame 18, so that the mutual adjustment of the needle tip positions can be realized by using the balance lever mechanism.

[0045] The preloading tension pin 23 is set to obtain a preloading force once the flying probe module is assembled, so that the first rocker 124 in the tool holder closely adheres to the cylindrical surface of the preloading tension pin 23, which is sufficient to ensure that the flying probe module has sufficient rigidity and stability during the high-speed operation of the flying probe tester.

[0046] The self-adjusting component is arranged on the second elastic frame 18 to adjust the tip position of the first blade 3 or the second blade 4 by using the principle of the balance lever.

[0047] The self-adjusting component includes a tripod 7, a rotating blade 72 and a rotating rod 74. One end of the tripod 7 is connected with a connecting column 14, and the other end is provided with a fixing groove 71. The tripod 7 is connected with the mounting hole 122 through the connecting column 14. The middle part of the rotating blade 72 is provided with a rotating hole 73. The rotating blade 72 is rotatably connected with the rotating rod 74 through the rotating hole 73. The rotating rod 74 passes through the rotating hole 73 and is tightly connected with the fixing groove 71. The two ends of the rotating blade 72 are attached to the upper ends of the adjusting rods 15.

[0048] As Figure 8 shown, the tip height of the second blade 4 is higher than that of the first blade 3. The self-adjusting component uses the principle of the balance lever. The flying probe module advances under the drive of the Z-axis motor. The tip of the first blade 3 hits the PCB board. As the feed amount increases, the adjusting rod 15 on the tool holder mounting the first blade 3 is jacked up under the reaction force of the PCB board, causing the tool holder to swing around the left position of the first connecting rod 125, thereby pushing one end of the rotating blade 72 on the first blade 3 to swing upward around the rotating rod 74. Furthermore, the rotating blade 72 rotates counterclockwise, pressing down the other adjusting rod 15 on the other side of the rotating blade 72, so that the second blade 4 obtains a new power source in addition to the driving force of the Z-axis motor. Finally, the tips of the first blade 3 and the second blade 4 converge and hit the surface of the PCB board in a very short time.

[0049] This balance lever mechanism not only compensates for the injection molding errors generated during the injection molding process of the tool holder, but also reduces the technical requirements during the assembly process and improves the manufacturing efficiency of the flying probe module.

[0050] In this embodiment, the working principle of a self-adjusting flying probe module for four-terminal testing is as follows:

[0051] First, install the tool holder, including the following steps:

[0052] 1. Use a grinding stone to polish the mating surfaces of the two tool holders to eliminate the burrs and flash formed during the injection molding process of the injection molded parts;

[0053] 2. Use glue to bond the insulating column 191 to the tool holder on the left side and attach the insulating sheet 19;

[0054] III. Combine two tool holders into a whole using five connecting posts 14, and assemble the adjusting rod 15 at the same time, so that the distance between the upper end surface of the adjusting rod 15 and the bottom surface of the tool holder is 7.2 - 7.3 mm;

[0055] IV. Assemble the tripod 7, the rotating blade 72, the rotating rod 74, and the two connecting posts 14 for installing the tripod 7, so that the rotating blade 72 can rotate flexibly and freely around the center line of the rotating rod 74, thereby forming a balance lever mechanism. At the same time, the distance between the rotating blade 72 and the bottom surface of the tool holder is 8 - 8.15 mm;

[0056] V. Assemble the blade and conduct the four-wire method test on the PCB board.

[0057] Due to the manufacturing errors of the die-forming parts, the dimensional errors of plastic parts caused by the fluctuation of plastic shrinkage rate, the errors caused by inaccurate selection of shrinkage rate when designing the die, the surface wear of the die-forming parts, and the dimensional change values caused by the clearance or installation errors of the movable or fixed die-forming parts, all of which will affect the dimensional accuracy of plastic parts, resulting in situations such as the slots at the blade installation positions being one in front and one behind, with different heights after the two tool holders are assembled, which will affect the assembly and use of the flying probe module. Thanks to the high toughness of PBT, using the tripod, the rotating rod, and the rotating blade, a balance lever mechanism is formed by relying on the combination of two small columns, which ingeniously solves the problem of inconsistent slots caused by dimensional deviations of plastic parts.

[0058] In the description of this specification, the descriptions referring to terms such as "one embodiment", "example", "specific example", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0059] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed.

Claims

1. A self - adjusting flying needle module for four - terminal testing, the self - adjusting flying needle module is arranged on a flying needle machine, Characterized in that, The self - adjusting flying needle module includes: Two elastic tool holders, the tool holders are installed and connected to the flying needle machine through needle seats (2). The tool holders include connecting columns (14), a first elastic frame (12) and a second elastic frame (18). The first elastic frame (12) is provided with connection holes (11) distributed in an array. The two tool holders are connected and fixed through the cooperation of the connecting columns (14) and the connection holes (11); Detection blades, the detection blades are arranged at one end of the tool holder and are used for four - terminal testing of the PCB board. The detection blades include a first blade (3) and a second blade (4). An insulating sheet (19) is arranged between the first blade (3) and the second blade (4), and the tip height of the second blade (4) is higher than that of the first blade (3); A self - adjusting component, the self - adjusting component is connected to the tool holder, the self - adjusting component is arranged on the detection blade and is used for adjusting the tip position of the detection blade. The self - adjusting component is arranged on the second elastic frame (18). The self - adjusting component includes a tripod (7), a rotating blade (72) and a rotating rod (74). One end of the tripod (7) is connected to the mounting holes (122) on the two tool holders through two connecting columns (14), and the other end is provided with a fixing groove (71). The rotating blade (72) is rotationally connected to the rotating rod (74) through a rotating hole (73) arranged in the middle thereof, and the rotating rod (74) passes through the rotating hole (73) and is tightly connected to the fixing groove (71); The second elastic frame (18) is provided with a fixing hole (17), and an adjusting rod (15) is installed on the fixing hole (17). The upper end of the adjusting rod (15) is in contact with both ends of the rotating blade (72), and the first blade (3) and the second blade (4) are adjusted through the principle of the balance lever.

2. A self - adjusting flying needle module for four - terminal testing according to claim 1, Characterized in that, The needle seat (2) is provided with a mounting groove (24), a first threaded hole (22) is arranged in the mounting groove (24), and a pre - pressing and tensioning pin (23) is installed in the mounting groove (24) for providing a pre - pressure to the tool holder. A connecting plate (20) is installed on the needle seat (2), and an adjustable reflective photoelectric switch is installed on the needle seat (2) for monitoring the change of the pressure value of the flying needle module during the testing process.

3. A self - adjusting flying needle module for four - terminal testing according to claim 2, Characterized in that, The first elastic frame (12) is a rectangular structure composed of a fixing rod (126), a first connecting rod (125) and two first rocker arms (124). The two first rocker arms (124) are connected and arranged between the fixing rod (126) and the first connecting rod (125); One end of the first elastic frame (12) is provided with a mounting hole (122), and one end of the second elastic frame (18) is fixedly provided with a second connecting rod (184), and a jack (181) is arranged on the second connecting rod (184).

4. A self - adjusting flying needle module for four - terminal testing according to claim 3, Characterized in that, The second elastic frame (18) is a rectangular structure composed of a first connecting rod (125), a second connecting rod (184) and two second rocker arms (182). The tool holder is made of PBT material. The thicknesses at both ends of the second connecting rod (184) are thinner than the remaining positions to form elastic pieces. A tool groove (16) is provided on one side of the second connecting rod (184) for installing a detection blade.

5. A self-adjusting flying probe module for four-terminal testing according to claim 3, characterized in that, a connecting block (10) is provided in the first elastic frame (12). A bolt passes through a through hole (101) in the connecting block (10) and is connected to a first threaded hole (22). A grinding surface (121) is provided on one side of the tool holder, and the grinding surfaces (121) of the two tool holders are attached and connected.

6. A self-adjusting flying probe module for four-terminal testing according to claim 3, characterized in that, the insulating sheet (19) is fixedly connected to the jack (181) through an insulating column (191), so that the insulating sheet (19) is installed between the first blade (3) and the second blade (4).

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