A dual lenticular contact based pogo pin connector

Abstract

This invention discloses a spring-loaded connector based on a double-convex button contact, belonging to the field of electrical connector technology. It aims to solve the problems of high contact resistance, easy wear, and transient signal interruption caused by the point contact of traditional spring-loaded connectors. The connector includes a unidirectional open sleeve, inside which, from bottom to opening, are sequentially assembled an elastic element, a button contact, and a needle, with the needle tip extending out of the sleeve. Two symmetrical annular protrusions are provided on the periphery, each composed of multiple strands of metal wire with a spacing greater than half the axial length. During testing, the needle contacts the chip under test and is subjected to axial pressure, compressing the button contact and elastic element. The annular protrusions contact the inner wall of the sleeve, forming an electrical signal conduction path of "contact point - needle - button contact - sleeve". After testing, the elastic element and button contact spring back, and the protrusions detach from the inner wall of the sleeve and reset. This connector improves contact stability and lifespan, making it suitable for high-reliability chip testing scenarios.

Description

Technical Field

[0001] This invention belongs to the field of electrical connector technology, and particularly relates to a spring-loaded connector based on a double-convex-patterned button contact. Background Technology

[0002] With the rapid development of electronic technology, chips are widely used in many fields due to their superior performance. Testing is an essential step in ensuring the reliability and performance of chips. Among various testing methods, Pogo-Pin testing plays a crucial role.

[0003] Traditional spring-loaded connectors typically use a metal ball as its contact element. Under spring pressure, the ball forms an approximate point contact with the pin tip to conduct current. However, this structure has inherent drawbacks: First, the small point contact area results in high and unstable contact resistance; second, the ball experiences sliding friction with the pin and spring, leading to wear and tear over time, generating metal debris and causing failure; third, the ball surface is easily oxidized or contaminated, and the oxide film is difficult to remove through contact pressure, causing poor contact; finally, under high-speed vibration, the point contact is prone to momentary disconnection, resulting in transient signal interruption.

[0004] To address the aforementioned issues, various design improvements have been implemented, such as changes to the ball material, coating, or spring pressure. However, none of these improvements have fundamentally altered the physical characteristics of point contact, resulting in limited effectiveness. Summary of the Invention

[0005] To address the problems in the prior art, the present invention proposes the following technical solution: A spring-loaded connector based on a double-convex button contact includes a unidirectional open sleeve, which is a current-carrying conductor and is connected to the electrical signal at the other end of the test. The bottom of the sleeve is sequentially fitted with an elastic element, a button contact element, and a needle, with the tip of the needle extending out of the opening of the sleeve. The outer periphery is provided with two symmetrically arranged annular protrusions, which are made of multiple strands of metal wires. The distance between the two annular protrusions is greater than half of the axial length, which can ensure that only the annular protrusions contact the inner wall of the sleeve when under pressure. The double-ring convex hull structure design in this invention, when compressed, contacts the inner wall of the sleeve, providing two main multi-faceted contact areas, which greatly increases the effective contact area, significantly reduces contact resistance and improves stability. Compared with the point contact of metal balls, the surface contact mode of this invention is less likely to break when subjected to vibration, ensuring the continuity of signal transmission. Moreover, the redundant design of the two contact surfaces forms a dual-path contact conduction, effectively reducing the failure rate. Furthermore, the overall cylindrical shape and the double-ring convex structure with a certain spacing allow the two ring convex bulges to contact the inner wall of the casing first when subjected to axial compression, preventing other parts from contacting the inner wall of the casing and thus avoiding wear on other parts.

[0006] In this invention, the structure of the button contact not only meets the requirements of low-profile testing, but also, due to its certain flexibility and elasticity, the annular convex bulge will produce slight sliding and deformation when under pressure. The sliding friction with the sleeve can effectively scratch the oxide layer and contaminants on its contact surface, ensuring direct contact between metals and further guaranteeing the stability of electrical signal transmission.

[0007] During testing, the tip of the needle contacts the contact point of the chip or circuit board under test and applies axial pressure. The button contact and elastic element are compressed, and the elastic pressure ensures good contact between the needle and the contact point. At the same time, the annular convex bulge contacts the inner wall of the sleeve under compression deformation, thus forming an electrical signal conduction path of: contact point-needle-button contact-sleeve. After the test, the elastic element and button contact rebound, causing the annular convex bulge to return to its initial non-conductive state of not contacting the inner wall of the sleeve.

[0008] As a preferred embodiment of the above technical solution, the elastic element includes an axially arranged connecting pin and a spring, with the top of the connecting pin abutting against the bottom, and the bottom of the connecting pin and the top of the spring abutting against each other.

[0009] As a preferred embodiment of the above technical solution, the bottom of the connecting pin is machined with a sharp corner, and the sharp corner extends into the top of the spring; ensuring reliable contact between the connecting pin and the spring.

[0010] As a preferred embodiment of the above technical solution, the needle includes guide portions at both ends and an elongated portion in the middle. The top end of the guide portion at the head end is machined into a serrated shape. The connection between the guide portion at the tail end and the elongated portion forms a limiting step. The serrated design ensures good contact with the contact point and avoids misalignment and slippage.

[0011] As a preferred embodiment of the above technical solution, the inner wall of the sleeve is provided with a riveting protrusion. After the test, the elastic element and the button contact element rebound, and the riveting protrusion abuts against the limiting step to limit the needle tip.

[0012] As a preferred embodiment of the above technical solution, when the riveting protrusion forms a limiting state for the needle, the elastic element is in a lightly compressed state, and the annular protrusion does not contact the inner wall of the sleeve.

[0013] The beneficial effects of this invention are as follows: The spring-load connector based on a double-convex button contact element provided by this invention fundamentally solves a series of problems caused by the point contact structure of traditional spring-load connectors. Its core innovation lies in the symmetrically arranged double-ring protrusions on the periphery. This structure forms two multi-faceted contact areas with the inner wall of the sleeve under pressure during testing. Compared to the point contact of traditional metal ball bearings, this significantly increases the effective contact area, significantly reduces contact resistance, and improves signal transmission stability. Even under high-speed vibration environments, the redundant design of the double contact surfaces can prevent signal interruption, effectively reducing the failure rate. Simultaneously, the design of the double-ring protrusions being spaced more than half the axial length ensures that only the protrusion portion contacts the inner wall of the sleeve under pressure, avoiding wear on other parts and extending the component's service life. Furthermore, its inherent flexibility and elasticity allow the ring protrusions to slightly slide and deform under pressure, scraping away the oxide layer and contaminants on the contact surface through friction with the sleeve, further ensuring direct metal-to-metal contact and ensuring stable electrical signal transmission. In addition, the fit between the connecting pin and the spring in the elastic component, the serrated tip of the pin, and the matching of the limiting step with the rivet protrusion of the sleeve not only achieve reliable contact and electrical signal conduction during testing, but also ensure accurate reset after testing, ensuring that the initial state is consistent for each test, meeting the requirements of chip testing for stability, reliability and miniaturization, and improving testing efficiency and result accuracy. Attached Figure Description

[0014] Figure 1 The image shown is a front view of a spring-loaded connector based on a double-convex button contact element in an embodiment. Figure 2 The diagram shown is a schematic diagram of the internal structure of a spring-loaded connector based on a double-convex button contact in the embodiment under its natural state. Figure 3 The diagram shown is a schematic representation of the internal structure of a spring-loaded connector based on a double-convex button contact element under test compression conditions.

[0015] Explanation of reference numerals in the attached figures: 10. Sleeve; 20. Elastic element; 21. Connecting pin; 22. Spring; 30. Button contact element; 31. Annular protrusion; 40. Needle; 41. Guide part; 42. Slender part; 400. Limiting step; 50. Rivet protrusion. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments.

[0017] Test preparation phase: Install the spring connector at the designated station of the chip test fixture, so that the end of the sleeve 10 away from the opening is stably connected to the electrical signal terminal of the test equipment, ensuring that there is no contact gap between the sleeve 10 and the test equipment; at the same time, fix the chip or circuit board to be tested in the corresponding test position, and adjust the position so that the chip contact point is precisely aligned with the serrated tip of the needle 40 to avoid misalignment during testing.

[0018] During the test conduction phase, the test fixture in Figure 3 is activated, driving the spring connector to move towards the chip under test. After the serrated structure at the tip of the needle 40 contacts the chip contact point, the fixture continues to apply axial pressure. As the pressure increases, the needle 40 moves into the sleeve 10, thereby pushing the button contact 30 and the elastic element 20 to compress synchronously. When the button contact 30 is compressed and deformed, its two annular protrusions 31 expand outward and make close contact with the inner wall of the sleeve 10, forming a complete electrical signal conduction path of "chip under test contact point - needle 40 - button contact 30 - sleeve 10 - test equipment". During this process, the sliding friction between the annular protrusions 31 and the inner wall of the sleeve 10 will scratch the oxide layer and contaminants on the contact surface, ensuring direct contact between metals and avoiding abnormal signal transmission caused by poor contact.

[0019] The reset phase after testing corresponds to Figure 2. After the chip test is completed, the test fixture drives the spring connector away from the chip under test, and the axial pressure on the needle 40 disappears. Under the rebound force of the elastic element 20, the connecting needle 21, the button contact 30, and the needle 40 move upward along the axial direction of the sleeve 10 until the limiting step 400 of the needle 40 abuts against the riveting protrusion 50 of the sleeve 10, and the device returns to the initial state. At this time, the button contact 30 rebounds and resets, the annular protrusion 31 disengages from the inner wall of the sleeve 10, the electrical signal conduction path is broken, and the next test operation or the chip under test can be replaced.

[0020] Key structural function: During the testing of the function of the double annular convex 31, the multi-faceted contact area formed by the two annular convex 31 significantly increases the effective contact area compared to the point contact of traditional ball bearings. This not only reduces contact resistance but also improves the stability of signal transmission. Even under high-speed vibration environments, the redundant design of the double contact surface can prevent signal interruption. At the same time, because other parts of the button contact 30 do not contact the inner wall of the sleeve 10, overall wear is reduced, extending the service life of the device.

[0021] The serrated tip of the needle 40 increases the contact friction between the needle 40 and the chip, preventing contact misalignment caused by slight displacement during testing and ensuring continuous conduction of electrical signals during testing. The cooperation between the limiting step 400 and the riveting protrusion 50 not only prevents the needle 40 from coming out, but also provides a clear positioning reference for device reset, ensuring the consistency of the initial state for each test.

[0022] In summary, the spring-loaded connector in this embodiment, through its reasonable structural design, solves the inherent defects of traditional spring-loaded connectors. It is suitable for scenarios with high requirements for signal transmission stability and device reliability, such as chip electrical performance testing, and can effectively improve testing efficiency and the accuracy of test results.

[0023] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it.

Claims

1. A spring-loaded connector based on a double-convex button contact, characterized in that, The sleeve (10) includes a one-way opening. From the bottom to the opening of the sleeve (10), an elastic element (20), a button contact element (30) and a needle (40) are sequentially assembled, and the tip of the needle (40) extends out of the opening of the sleeve (10). The outer periphery of the button contact (30) is provided with two symmetrically arranged annular protrusions (31). The annular protrusions (31) are made of multiple strands of metal wire, and the distance between the two annular protrusions (31) is greater than half the axial length of the button contact (30), which can ensure that only the annular protrusion part contacts the inner wall of the sleeve when pressure is applied. During testing, the tip of the needle (40) contacts the contact point of the chip or circuit board under test and applies axial pressure. The button contact (30) and the elastic element (20) are compressed. Under elastic pressure, the needle (40) and the contact point make good contact. At the same time, the annular convex bulge (31) contacts the inner wall of the sleeve (10) under the compression deformation of the button contact (30), thereby forming an electrical signal conduction path of: contact point-needle (40)-button contact (30)-sleeve (10). After the test, the elastic element (20) and the button contact (30) rebound, so that the annular convex bulge (31) returns to the initial non-conductive state of not contacting the inner wall of the sleeve (10). The elastic element (20) includes an axially arranged connecting pin (21) and a spring (22). The top of the connecting pin (21) abuts against the bottom of the button contact (30), and the bottom of the connecting pin (21) and the top of the spring (22) abut against each other. The needle (40) includes guide portions (41) at both ends and an elongated portion (42) in the middle. The top end of the head guide portion (41) is serrated. The connection between the tail guide portion (41) and the elongated portion (42) forms a limiting step (400). The inner wall of the sleeve (10) is provided with a riveting protrusion (50). After the test, the elastic element (20) and the button contact element (30) rebound, and the riveting protrusion (50) abuts against the limiting step (400) to limit the needle (40).

2. A spring-loaded connector based on a double-convex button contact element according to claim 1, characterized in that, The bottom of the connecting pin (21) is machined with a sharp corner, and the sharp corner extends into the top of the spring (22).

3. A spring-loaded connector based on a double-convex button contact element according to claim 1, characterized in that, When the rivet protrusion (50) forms a limiting state on the needle (40), the elastic element (20) and the button contact element (30) are in a lightly compressed state, and the annular protrusion (31) does not contact the inner wall of the sleeve (10).

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