Low-resistance spring probe structure

Abstract

The utility model discloses a spring probe structure with low resistance, which comprises a bottom plunger, a spring, a top plunger and a sleeve, the bottom plunger, the spring and the top plunger are sequentially arranged in the sleeve, the top of the bottom plunger and the bottom of the top plunger penetrate through the sleeve, and the top of the top plunger penetrates through the sleeve. The bottom end of the bottom plunger makes contact with one end of the spring, the top end of the top plunger makes contact with the other end of the spring, and the top end of the top plunger is of an eccentric inner conical structure. Friction force between the top plunger and the sleeve is increased, fluctuation of resistance is further reduced, and resistance almost has no fluctuation.

Description

Technical Field

[0001] This utility model relates to the technical field of spring probes, specifically to a low-resistance spring probe structure. Background Technology

[0002] Spring probes are precision connectors used in electronic products such as mobile phones, communications, automobiles, medical devices, and aerospace. A spring probe typically consists of a needle, a tube, and a spring. The spring is located inside the tube, and the needle is inserted inside the tube. When the needle is squeezed by a component, it compresses the spring. Under the action of the spring's thrust, the needle can move axially along the tube. The outer surface of the needle contacts the inner surface of the tube, and an electrical signal is transmitted from the needle to the tube. This allows for the rapid detection of faulty components or assemblies and the accurate location and classification of defects. Therefore, the stability and magnitude of the resistance value of the spring probe itself are subject to high requirements.

[0003] The existing double-acting spring probe has a large contact friction between the outer surface of the plunger (equivalent to the needle) and the inner surface of the sleeve (equivalent to the needle tube), which has a certain effect on resistance fluctuation. However, due to the large contact friction, both surfaces wear out severely, and the processing requirements are high and the processing is difficult, resulting in a relatively short service life, generally 10,000 to 100,000 times. Utility Model Content

[0004] To overcome the aforementioned problems, the purpose of this invention is to provide a low-resistance spring probe structure that increases the friction between the plunger and the sleeve, further reducing resistance fluctuations, with virtually no resistance fluctuations.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is: a low-resistance spring probe structure, including a bottom plunger, a spring, a top plunger, and a sleeve. The bottom plunger, spring, and top plunger are sequentially installed into the sleeve. The top of the bottom plunger and the bottom of the top plunger pass through the sleeve. The bottom end of the bottom plunger contacts one end of the spring, and the top end of the top plunger contacts the other end of the spring. The top end of the top plunger is configured as an eccentric inner conical structure. The purpose of the eccentric inner conical structure is to increase the contact force between the outer surface of the top plunger and the inner surface of the sleeve, so that the two are reliably connected. The outer diameter of the top plunger is made into a complete cylinder to reduce sliding friction.

[0006] Preferably, the center of the eccentric inner conical structure is not on the same horizontal line as the center of the top plunger and the center of the spring compression. When the spring is compressed, it will also compress the eccentric inner conical structure, causing the top plunger to apply pressure towards the inner wall of the sleeve, further increasing the friction between the outer surface of the top plunger and the inner surface of the sleeve.

[0007] Preferably, the bottom plunger includes an integrally formed first plunger head and a first plunger tail, with a first boss structure provided between the first plunger head and the first plunger tail. The first plunger head passes through the sleeve, and the first plunger tail is located inside the sleeve. The sleeve is secured at the first boss structure by a rolled edge.

[0008] Preferably, the top plunger includes an integrally formed second plunger head and a second plunger tail, a second boss structure is provided between the second plunger head and the second plunger tail, the second plunger tail passes through the sleeve, the second plunger head is located inside the sleeve, and the sleeve is secured at the second boss structure by a rolled edge.

[0009] Preferably, the interior of the first plunger tail at the end in contact with the spring is provided with a groove for placing the spring. The spring is placed in the groove, making it more stable and less prone to displacement during compression.

[0010] Preferably, the eccentric inner conical structure is located at the top of the second plunger head.

[0011] The beneficial effects of this utility model are: the outer surface of the top plunger and the inner surface of the sleeve have stable contact structure, which further increases the friction between the two. Therefore, the resistance value can be controlled very stably and low (within 15 milliohms), and even the resistance is almost without fluctuation. It is suitable for occasions with high requirements for resistance value and stability. It can carry a rated current of more than 15A, and the processing difficulty is low. It has a long service life and the service life of testing can reach 300,000 times. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of this embodiment;

[0013] Figure 2 This is a schematic diagram of the working state of this embodiment;

[0014] Figure 3 This is a schematic diagram of the top plunger in this embodiment;

[0015] Figure 4 This is a schematic diagram of the horizontal line of the top plunger in this embodiment;

[0016] Figure 5 This is a graph showing the resistance and stability when applied in this embodiment.

[0017] In the diagram: 1. Bottom plunger; 2. Spring; 3. Top plunger; 4. Sleeve; 5. First plunger head; 6. First plunger tail; 7. First boss structure; 8. Second plunger head; 9. Second plunger tail; 10. Second boss structure; 11. Eccentric inner conical structure; 12. Groove. Detailed Implementation

[0018] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the scope of protection of the present invention.

[0019] See Figures 1-4 This embodiment discloses a low-resistance spring probe structure, belonging to a double-acting spring probe, including a bottom plunger 1, a spring 2, a top plunger 3, and a sleeve 4. The bottom plunger 1, spring 2, and top plunger 3 are sequentially installed into the sleeve 4. The bottom plunger 1 includes an integrally formed first plunger head 5 and a first plunger tail 6, with a first boss structure 7 provided between the first plunger head 5 and the first plunger tail 6. The first plunger head 5 passes through the sleeve 4, and the first plunger tail 6 is located inside the sleeve 4. The sleeve 4 is secured to the first boss structure 7 by the edge-rolling and finishing of an edge-rolling machine, thereby fixing the bottom plunger 1. The top plunger 3 includes an integrally formed second plunger head 8 and a second plunger tail 9, with a second boss provided between the second plunger head 8 and the second plunger tail 9. Structure 10, the second plunger tail 9 passes through the sleeve 4, the second plunger head 8 is located inside the sleeve 4, the sleeve 4 is secured at the second boss structure 10 by a rolled edge, the bottom end of the first plunger tail 6 contacts one end of the spring 2, the top end of the second plunger head 8 contacts the other end of the spring 2, the top end of the top plunger 3 is set as an eccentric inner conical structure 11, the eccentric inner conical structure 11 is located at the top end of the second plunger head 8, the center of the eccentric inner conical structure 11 is not on the same horizontal line as the center of the top plunger and the center of the spring compression, the first plunger tail 6 at the contact end with the spring 2 is provided with a groove 12 for placing the spring 2, the spring 2 is placed in the groove 12 to make it more stable and less prone to displacement during compression.

[0020] When pressure is applied to the plungers at both ends, the two plungers move along the axial direction, causing the spring 2 inside the sleeve 4 to compress and deform. Because the end face of the spring 2 contacts the eccentric inner conical structure 11 of the top plunger 3 in an eccentric contact, the spring 2 will generate a lateral thrust on the top plunger 3, causing the outer surface of the second plunger head 8 to make tight contact with the inner wall of the sleeve 4, forming sliding friction. The electrical signal is transmitted from the top plunger 3 to the sleeve 3, and then from the bottom plunger 1. After the transmission is completed, the top plunger 3 will spring back to its initial position under the action of elasticity. The above process is repeated for each signal transmission, and this structure can ensure the consistency of each signal transmission.

[0021] See Figure 5 As shown in the figure, the graph of the present invention applied to test the resistance and stability of the connector (the horizontal axis is the service life and the vertical axis is the resistance) shows that the resistance performance is stable.

[0022] The above embodiments are only for illustrating the technical concept and features of this utility model. Their purpose is to enable those skilled in the art to understand the content of this utility model and implement it. They cannot be used to limit the protection scope of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be covered within the protection scope of this utility model.

Claims

1. A low-resistance spring probe structure, comprising a bottom plunger, a spring, a top plunger, and a sleeve, wherein the bottom plunger, spring, and top plunger are sequentially inserted into the sleeve, characterized in that, The top of the bottom plunger and the bottom of the top plunger pass through the sleeve. The bottom end of the bottom plunger contacts one end of the spring, and the top end of the top plunger contacts the other end of the spring. The top end of the top plunger is configured as an eccentric inner conical structure.

2. The low-resistance spring probe structure according to claim 1, characterized in that, The center of the eccentric inner conical structure is not on the same horizontal line as the center of the top plunger and the center of the spring compression.

3. The low-resistance spring probe structure according to claim 1, characterized in that, The bottom plunger includes an integrally formed first plunger head and a first plunger tail. A first boss structure is provided between the first plunger head and the first plunger tail. The first plunger head passes through the sleeve, and the first plunger tail is located inside the sleeve. The sleeve is secured at the first boss structure by a rolled edge.

4. The low-resistance spring probe structure according to claim 1, characterized in that, The top plunger includes an integrally formed second plunger head and a second plunger tail. A second boss structure is provided between the second plunger head and the second plunger tail. The second plunger tail passes through the sleeve, and the second plunger head is located inside the sleeve. The sleeve is secured at the second boss structure by a rolled edge.

5. The low-resistance spring probe structure according to claim 3, characterized in that, The first plunger tail, which contacts the spring, has a groove inside for placing the spring.

6. The low-resistance spring probe structure according to claim 4, characterized in that, The eccentric inner conical structure is located at the top of the second plunger head.

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