Test probe for circuit board test fixture

Abstract

The utility model relates to a test probe for a circuit board test fixture, which comprises a probe body, the surface of the probe body is sequentially coated with a nickel plating layer and a gold plating layer from inside to outside, and the surface of the gold plating layer between the probe head and the probe tail of the probe body is also coated with a first insulating layer; the needle head is provided with a blunt end, and the surface of the gold-plated layer, located between the blunt end and the first insulating layer, of the needle head is further covered with a second insulating layer. Therefore, the contact area with the circuit board test contact is increased, the service life is prolonged, the to-be-tested circuit board is prevented from being punctured, the risks of micro short circuit and short circuit are avoided, and the overall performance of the test fixture is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of circuit board testing equipment, and particularly relates to a test probe for a circuit board testing fixture. Background Art

[0002] At present, circuit board manufacturers at home and abroad all detect the finished circuit boards produced and processed through (probe type) testing fixtures. These circuit board testing fixtures are all composed of a needle disk, a wire disk, and test probes installed on the needle disk. Among them, the tips of the test probes are very sharp (as Figure 1 shown), and the contact area with the circuit board test contacts during the test is extremely small. It is not only easy to have poor contact, but also easy to scratch the circuit board. At the same time, the gold plating layer on the surface of the tip of the needle is easy to fall off, and the service life is short; and because the needle holes provided on the needle disk for the needles to pass through are set very densely, the distance between adjacent two needle holes is about 5μm, so the tips of adjacent test probes often have micro-short circuits or short circuits. Therefore, the overall performance stability of the existing circuit board testing fixtures is relatively low. Summary of the Utility Model

[0003] In order to solve the above problems existing in the prior art, the utility model provides a test probe for a circuit board testing fixture.

[0004] In order to solve the above technical problems, the utility model adopts the following technical scheme:

[0005] The test probe for a circuit board testing fixture described in the utility model includes a probe body. The surface of the probe body is successively coated with a nickel plating layer and a gold plating layer from the inside to the outside. Moreover, a first insulating layer is also coated on the surface of the gold plating layer between the tip and the tail of the probe body;

[0006] The tip has a blunt tip, and a second insulating layer is also coated on the surface of the gold plating layer between the blunt tip and the first insulating layer of the tip.

[0007] Further, the thickness of the second insulating layer is less than the thickness of the first insulating layer.

[0008] Further, the thickness of the first insulating layer is 0.005mm, and the thickness of the second insulating layer is 0.002mm.

[0009] Further, the total length of the tip is 3mm, and the length of the blunt tip is 0.03mm.

[0010] Advantages of the Utility Model

[0011] Through the above solution, the test probe for the circuit board test fixture of the present utility model not only increases the contact area with the circuit board test contacts, but also extends the service life, and further avoids scratching the circuit board to be tested, as well as the risks of micro short circuit and short circuit, improving the overall performance of the test fixture. Description of the Drawings

[0012] Figure 1 is a schematic structural diagram of the needle tip of the existing test probe;

[0013] Figure 2 is a schematic structural diagram of the test probe for the circuit board test fixture of the present utility model;

[0014] Figure 3 is Figure 2 a schematic cross-sectional view of the test probe for the circuit board test fixture of the present utility model along A-A;

[0015] Figure 4 is a schematic structural diagram of the test probe with a size of 70 μm in the embodiment of the present utility model;

[0016] Figure 5 is a partial physical diagram after nickel plating and gold plating during the preparation process of the test probe with a size of 70 μm in the embodiment of the present utility model.

[0017] Description of the reference numerals: 1. Probe body, 2. Needle tip, 21. Blunt tip, 3. Needle tail, 4. Nickel plating layer, 5. Gold plating layer, 6. First insulating layer, 7. Second insulating layer. Detailed Embodiments

[0018] In order to make the objectives, technical solutions and advantages of the present utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0019] As Figures 2 to 4 shown, in the embodiment of the present utility model, a test probe for a circuit board test fixture includes a probe body 1, and the two ends of the probe body 1 are respectively a needle tip 2 and a needle tail 3. The surface of the probe body 1 (including the needle tip 2 and the needle tail 3) is sequentially coated with a nickel plating layer 4 and a gold plating layer 5 from the inside to the outside, and a first insulating layer 6 is further coated on the surface of the gold plating layer 5 between the needle tip 2 and the needle tail 3, and the thickness of the first insulating layer 6 is 0.005 mm.

[0020] Again, as Figure 2 , Figure 4 and Figure 5As shown, the needle 2 has a blunt tip 21. The total length of the needle 2 is 3 mm, and the length of the blunt tip 21 is 0.03 mm. The surface of the gold plating layer 5 between the blunt tip 21 and the first insulating layer 6 of the needle 2 (i.e., the part of the needle 2 passing through the pinhole on the circuit board test fixture) is also covered with a second insulating layer 7. The thickness of the second insulating layer 7 is less than that of the first insulating layer 6, and the specific thickness is 0.002 mm. Both the first insulating layer 6 and the second insulating layer 7 are polymer coatings, such as polyimide coatings.

[0021] In the test probe of the present utility model, by using the blunt tip 21 for the needle 2, on the one hand, the adhesion of the plating layer is enhanced, and on the other hand, the contact area with the circuit board test contact during the test is increased (the contact area of the needle tip of the existing test probe during the test is 1 μm, and the contact area of the needle tip of the test probe of this application during the test is 5 μm). Thereby, the service life of the gold plating layer 5 of the needle 2 of the test probe is improved (the service life is increased by about 30% - 50%), the performance of the test fixture is enhanced, and the risk of scratching the circuit board to be tested is avoided. At the same time, the second insulating layer 7 avoids the risk of micro-short circuit and short circuit caused by the needle 2, enabling the test probe to pass a 1000M insulation test.

[0022] The test probe with a diameter of 70 μm in the embodiment of the present utility model was tested. The test results were as follows: After 500,000 times, the gold plating layer 5 on the surface of the blunt tip 21 began to fall off. After 1.5 million times, the gold plating layer 5 on the surface of the blunt tip 21 in contact with the circuit board test contact during the test completely fell off, and the test probe was scrapped. When an existing test probe with the same diameter of 70 μm was tested, after 300,000 times of testing, the gold plating layer at the tip of the needle began to fall off, and after 1 million times, the test probe was scrapped. It can be seen that through the above technical solution, the present utility model greatly improves the service life of the test probe, and further improves the service life and test performance of the test fixture.

[0023] The above is the preferred embodiment of the present utility model. It should be noted that for those of ordinary skill in the art of this technology, without departing from the principle of the present utility model, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present utility model.

Claims

1. A test probe for a circuit board test fixture, characterized in that, It includes a probe body (1), on the surface of which there are successively provided with a nickel plating layer (4) and a gold plating layer (5) from the inside to the outside, and a first insulating layer (6) is further provided on the surface of the gold plating layer (5) located between the needle tip (2) and the needle tail (3) of the probe body (1); The needle tip (2) has a blunt tip (21), and a second insulating layer (7) is further provided on the surface of the gold plating layer (5) of the needle tip (2) located between the blunt tip (21) and the first insulating layer (6).

2. The test probe for a circuit board test fixture according to claim 1, characterized in that, The thickness of the second insulating layer (7) is less than the thickness of the first insulating layer (6).

3. The test probe for a circuit board test fixture according to claim 2, wherein, The thickness of the first insulating layer (6) is 0.005 mm, and the thickness of the second insulating layer (7) is 0.002 mm.

4. The test probe for a circuit board test fixture according to claim 1, wherein, The total length of the needle tip (2) is 3 mm, and the length of the blunt tip (21) is 0.03 mm.

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