Traceless spring test pin and gold surface traceless test method

Abstract

The invention belongs to the technical field of circuit board detection, and discloses a traceless spring test needle and a gold surface traceless test method. Comprising a needle tube, a needle head and a first spring, a first sliding groove is formed in the inner wall of the needle tube, a sliding assembly is arranged in the first sliding groove, and the sliding assembly is located between the needle head and the first spring; the spiral first sliding groove is formed in the inner wall of the needle tube, and the sliding assembly is embedded into the spiral first sliding groove, so that the sliding assembly obtains circumferential rotating force while axially moving, and the needle head is driven to synchronously rotate. The needle head is in erasing type rotary contact when being in contact with a gold surface, so that a surface oxide layer or insulating stains are effectively removed; compared with a traditional vertical press-in mode, the rotating mechanism can greatly reduce the contact pressure in unit area; damage to micro welding spots and routing structures is reduced, and structural damage caused by local stress concentration is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of circuit board detection, and particularly relates to a non-marking spring test needle and a gold surface non-marking test method. Background Art

[0002] Spring-loaded test probes are an essential tool in the Chip-On-Board testing process. Their core role is to ensure stable current transmission and reliable contact, thereby effectively improving product yield. However, in applications involving high-end bonding electronic boards, while traditional test probes meet basic electrical performance requirements to a certain extent, they expose a series of significant issues that urgently require further optimization and improvement.

[0003] First, traditional test probes are typically designed with a high spring force and a small contact angle to achieve good current conduction performance. However, during the actual test pressure application process, this design is very likely to leave noticeable indentations or dents on the gold contact surface of the device under test. In high-end COB packaging structures, the chip is usually connected to the substrate via extremely fine gold or copper wires. These wire bonding points are not only tiny in size and precision in craftsmanship, but also relatively fragile in structure. If the pressure applied by the test probe is too great or the contact is too concentrated, it may cause wire deviation, breakage, or even solder joint peeling, seriously affecting the product yield and long-term reliability.

[0004] Secondly, to alleviate these issues, some manufacturers have experimented with test probes with wide-angle contact designs. These probes exert less pressure on the metal surface during contact, which can, to a certain extent, avoid surface indentations and thus protect the solder joint structure from damage. However, due to their large contact area and widespread pressure distribution, they often struggle to effectively penetrate oxide layers or other insulating layers that may exist on the metal surface. Failure to completely destroy these insulating layers can lead to increased contact resistance, momentary disconnection, signal misinterpretation, and other issues, compromising the accuracy and consistency of test results. Summary of the Invention

[0005] In view of this, the object of the present invention is to provide a non-marking spring test needle and a gold surface non-marking test method to solve the problems existing in the above-mentioned background technology.

[0006] In order to solve the above technical problems, the first technical solution of the present invention is a non-marking spring test needle, comprising a needle tube, a needle and a first spring, a first slide groove is provided on the inner wall of the needle tube, a sliding component is provided in the first slide groove, and the sliding component is located between the needle and the first spring; the direction of the first slide groove extends spirally along the axis of the needle tube, and when the needle contacts the test surface, the needle tube is pressed downward, and the sliding component slides relatively along the spiral first slide groove, and drives the needle to generate a needle under the guidance of the first slide groove. Rotational motion; the needle obtains circumferential rotational force while obtaining axial pressure, thereby effectively destroying the surface layer of the test surface, ensuring that the needle can accurately contact the substrate of the test surface, and achieving accuracy and consistency of the test results; the needle tube is divided into a rotating part and a pressure-applying part by the top of the first slide groove; when the sliding component is located in the rotating part, the needle obtains circumferential rotational force while obtaining axial pressure, ensuring effective destruction of the surface layer of the test surface; when the sliding component is located in the pressure-applying part, the needle obtains axial pressure to ensure stable contact with the test surface.

[0007] Preferably, the sliding assembly includes a limit member, a rotating member and a second spring, the limit member is located at the intersection of the rotating part and the pressure-applying part, the rotating member is slidably arranged in the first sliding groove, the second spring is arranged between the limit member and the rotating member, and the connecting end of the second spring and the rotating member is rotatably connected; when the sliding assembly is located at the rotating part, the second spring provides axial pressure to the rotating member.

[0008] Furthermore, guide slopes are provided on both the limit member and the rotating member; the guide slopes cooperate with each other in structural design so that the needle head obtains a more stable circumferential rotational force when it is in the rotating part; the second spring adopts a conical spring design; the conical spring can provide good axial pressure and radial support for the needle head when the rotating part moves; at the same time, with the help of the nonlinear change of elastic force of the conical spring, excessive damage to the surface of the test surface is avoided.

[0009] Furthermore, a second slide groove and a third slide groove are provided on the inner wall of the needle tube, and the bottom ends of the second slide groove and the third slide groove are both located at the intersection of the rotating part and the pressure-applying part, and the directions of the second slide groove and the third slide groove are arranged parallel to the axis direction of the needle tube; the second slide groove is connected to the first slide groove, and the second slide groove is used for the movable limit of the rotating part on the pressure-applying part; the third slide groove is used for the movable limit of the limit part on the pressure-applying part; before the rotating part and the limit part contact, the limit part is limited and fixed at the bottom end of the third slide groove; when the rotating part and the limit part contact, the rotating part pushes the limit part to move on the third slide groove.

[0010] Furthermore, the limiting member and the rotating member are provided with mutually matching slots and buckles; before the rotating member and the limiting member come into contact, only the elastic force of the second spring is transmitted to the needle head through the rotating member; after the rotating member and the limiting member come into contact, the slot and the buckle are engaged, and only the elastic force of the first spring is transmitted to the needle head through the sliding assembly.

[0011] Furthermore, a pushing member is provided on the side wall of the needle tube, and the pushing member passes through the inner and outer sides of the needle tube. The pushing member can move in the radial direction of the needle tube. A third spring is provided between the pushing member and the needle tube, and the third spring makes the pushing member protrude outside the needle tube. The pushing member acts on the slot and the buckle; when the slot and the buckle are engaged, the pushing member is pushed inward so that the pushing member acts on the slot and the buckle, so that the slot and the buckle are released from the engaged state, thereby realizing the separation of the rotating member and the limiting member.

[0012] Furthermore, a fixing part for constraining the movement of the limiting part is provided in the third slide groove, and a control part connected to the fixing part is provided in the first slide groove, and both the fixing part and the control part can slide in the radial direction of the needle tube; the fixing part only limits the upward movement of the limiting part; when the rotating part slides in the first slide groove, it pushes the control part to move radially of the needle tube and drives the fixing part to move; after the rotating part and the limiting part come into contact, the control part and the fixing part move into place, and the upward movement restriction of the limiting part by the fixing part is released.

[0013] Furthermore, the markless spring test needle can switch between a rotating operating state and a regular operating state; before the rotating part and the limiting part contact, only the elastic force of the second spring is transmitted to the needle head through the rotating part, and the markless spring test needle is in a regular operating state; after the rotating part and the limiting part contact, the slot and the buckle are engaged, and only the elastic force of the first spring is transmitted to the needle head through the sliding assembly, and the markless spring test needle is in a rotating operating state; before operation, the markless spring test needle is in a rotating operating state, and during operation, the needle head destroys the surface layer of the test surface through the circumferential rotation force, and then the markless spring test needle switches from the rotating operating state to the regular operating state, and after operation, the markless spring test needle is still in the regular operating state, so as to prevent the needle head from damaging the surface layer of the test surface again through the circumferential rotation force.

[0014] In order to solve the above technical problems, the second technical solution of the present invention is a gold surface non-marking testing method using the non-marking spring test needle described in the first technical solution.

[0015] The technical effects of the present invention are mainly reflected in the following aspects:

[0016] By providing a spiral first groove on the inner wall of the needle tube and embedding the sliding assembly within it, the sliding assembly generates circumferential rotational force while moving axially, driving the needle to rotate synchronously. This allows the needle to perform a "wiping" rotational contact when contacting the gold surface, effectively removing surface oxide layers or insulating stains. Compared to traditional vertical pressure-in methods, this rotational mechanism significantly reduces contact pressure per unit area, minimizing damage to tiny solder joints and wire bonding structures, and avoiding structural damage caused by localized stress concentration.

[0017] A conical spring serves as the primary source of force during the sliding assembly's rotational phase, leveraging its nonlinear stiffness to provide progressive force output during compression. Light pressure is applied during the initial stages of rotational cleaning to prevent excessive friction or scratches on the metal surface. As pressure deepens, the spring stiffness gradually increases, providing sufficient cleaning force. The conical structure also provides excellent radial support, enhancing the stability of the rotating component during rotation. This reduces abnormalities such as sliding assembly deflection and jamming, improving overall structural reliability. Furthermore, a matching guide ramp is provided between the stopper and the rotating component, optimizing force direction and rotational path through structural coordination.

[0018] A matching slot and snap-fit ​​structure are provided between the stopper and the rotating member. When the two come into contact, they automatically lock, changing the path of the spring force transmission. Initially, the second spring provides the required spring force for cleaning. After entering the stable contact phase, the first spring becomes the primary source of spring force, enabling automatic switching from low-pressure cleaning to high-pressure conduction. This prevents poor contact caused by external vibration or pressure fluctuations, improving test stability and electrical connection reliability. Furthermore, after resetting, the rotating member is locked by the snap-fit ​​structure, preventing it from being forced to rotate in the opposite direction. This unintended rotation could cause the needle to rub against the gold surface again as it leaves the test surface, causing unnecessary damage or residual marks. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural diagram of the present invention;

[0020] Figure 2 It is a cross-sectional view of the structure of the present invention;

[0021] Figure 3 for Figure 2 Cross-sectional view of the needle tube structure;

[0022] Figure 4 for Figure 2 Structural diagram of the sliding component;

[0023] Figure 5 for Figure 2 Structural cross-sectional view of the middle sliding assembly;

[0024] Figure 6 for Figure 2 Schematic diagram of the cooperation between the sliding component and the pushing member;

[0025] Figure 7 for Figure 2 Schematic diagram of the cooperation between the middle needle tube and the sliding assembly;

[0026] In the figure: 1. needle tube, 13. first slide groove, 14. second slide groove, 15. third slide groove, 16. fixing member, 17. control member; 2. needle; 3. first spring; 4. sliding assembly, 41. limiting member, 42. rotating member, 43. second spring, 44. guide slope, 45. slot, 46. buckle, 47. pushing member. DETAILED DESCRIPTION

[0027] The following is a further detailed description of the specific implementation methods of the present invention in conjunction with the accompanying drawings, so that the technical solutions of the present invention are easier to understand and grasp. In the embodiments, it should be understood that the orientation or positional relationship indicated by the terms "middle", "upper", "lower", "top", "right", "left end", "above", "back", "middle", etc. is based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, in this specific embodiment, if the connection or fixing method between the components is not particularly specified, the connection or fixing method can be fixed by bolts or pins commonly used in the prior art, or by pin connections, etc. Therefore, it will not be described in detail in this embodiment.

[0028] Example 1

[0029] This embodiment provides a non-marking spring test probe, which aims to solve the problems of traditional test probes in high-end COB (Chip On Board) packaging structures, such as solder joint damage, wire offset and breakage, and difficulty in penetrating the surface oxide layer caused by excessive contact pressure or improper contact method.

[0030] join Figure 1 ,、 Figure 2 The non-marking spring test needle includes a needle tube 1, a needle 2 and a first spring 3, wherein:

[0031] A first slide groove 13 is provided on the inner wall of the needle tube 1, and a sliding component 4 is provided in the first slide groove 13, and the sliding component 4 is located between the needle 2 and the first spring 3; the front end of the needle 2 is designed to have an arc-shaped end face with a certain taper to avoid local stress concentration caused by sharp contact; the direction of the first slide groove 13 extends spirally along the axial direction of the needle tube 1, and when the needle 2 contacts the test surface, the needle tube 1 is pressed downward, and the sliding component 4 slides relatively along the spiral first slide groove 13, and drives the needle 2 to rotate under the guidance of the first slide groove 13; the needle 2 obtains circumferential rotational force while obtaining axial pressure, thereby effectively destroying the surface layer of the test surface, ensuring that the needle 2 can accurately contact the matrix of the test surface, and achieving accuracy and consistency of the test results. The needle tube 1 is divided into a rotating part and a pressure-applying part by the top end of the first slide groove 13; when the sliding component 4 is located in the rotating part, the needle head 2 obtains axial pressure and circumferential rotational force at the same time, ensuring effective destruction of the surface layer of the test surface; when the sliding component 4 is located in the pressure-applying part, the needle head 2 obtains axial pressure to ensure stable contact with the test surface.

[0032] Specifically, during the test:

[0033] The test needle gradually approaches the gold surface to be tested, and the needle 2 first makes slight contact with the test surface; at this time, the sliding component 4 is located in the rotating part area of ​​the needle tube 1; as the downward pressing action proceeds, the sliding component 4 slides relatively along the spiral first slide groove 13; the spiral direction of the slide groove drives the sliding component 4 to produce rotational motion, and transmits it to the needle 2 through the connecting structure; the needle 2 obtains a certain circumferential rotational force while obtaining axial pressure. Under the action of rotation, the needle 2 makes "wiping" contact with the metal surface of the test surface; this rotational friction method can effectively destroy the oxide layer, stains or other insulating layers that may exist on the gold surface; at the same time, since the contact area is evenly distributed and the pressure is dispersed, no obvious indentation or dent will be left on the gold surface; compared with the traditional vertical pressing method, this rotation mechanism greatly reduces the contact pressure per unit area, thereby protecting tiny solder joints and wire bonding structures from damage. As the pressure continues to deepen, the sliding component 4 enters the pressure area of ​​the needle tube 1; at this time, the sliding component 4 no longer rotates and only performs linear displacement; the needle 2 is mainly subjected to the stable axial pressure provided by the first spring 3 to ensure a stable electrical connection with the test surface; at this stage, reliable substrate contact has been achieved between the needle 2 and the test surface, ensuring the stability of current transmission and the accuracy of signal acquisition.

[0034] See also Figure 4 、 Figure 5 , further, the specific composition of the sliding component 4 is as follows:

[0035] The sliding assembly 4 includes a stopper 41, a rotating member 42, and a second spring 43. The stopper 41 is located at the intersection of the rotating portion and the pressure-applying portion. The rotating member 42 slides within the first slot 13. The second spring 43 is disposed between the stopper 41 and the rotating member 42. The second spring 43 and the rotating member 42 are connected by a rotational connection to ensure that the spring does not affect the rotational freedom of the rotating member 42 during compression. When the sliding assembly 4 is in the rotating portion, the second spring 43 provides axial pressure to the rotating member 42. Guide slopes 44 are provided on both the limiting member 41 and the rotating member 42; the guide slopes 44 cooperate with each other in structural design, so that the needle 2 obtains a more stable circumferential rotational force when in the rotating part; the guide slopes 44 are used to guide the rotating member 42 to maintain a good force direction and rotational stability during the sliding process; the second spring 43 adopts a conical spring design; the conical spring can provide good axial pressure and radial support for the needle 2 when the rotating part moves; at the same time, with the help of the nonlinear change of elastic force of the conical spring, excessive damage to the surface of the test surface is avoided.

[0036] The conical spring has the following significant advantages: nonlinear elastic force change characteristics: as the compression amount increases, the spring stiffness gradually increases, thereby avoiding excessive pressure in the initial stage; good radial support capacity: the conical structure helps to improve the stability of the rotating part 42 during the rotation process, preventing deflection or jamming; strong adaptability: in the process of the needle 2 switching from rotational contact to stable pressing, it can smoothly transition the elastic force output and reduce impact and vibration.

[0037] See also Figure 3 , further, regarding the extended design of the inner wall groove structure of the needle tube 1:

[0038] A second slide groove 14 and a third slide groove 15 are provided on the inner wall of the needle tube 1, and the bottom ends of the second slide groove 14 and the third slide groove 15 are both located at the intersection of the rotating part and the pressure-applying part, and the directions of the second slide groove 14 and the third slide groove 15 are parallel to the axial direction of the needle tube 1; the second slide groove 14 is connected to the first slide groove 13, and the second slide groove 14 is used for the movable limit of the rotating part 42 on the pressure-applying part; when the sliding assembly 4 transitions from the rotating part to the pressure-applying part, the rotating part 42 can slide linearly along the second slide groove 14 without rotating; ensuring that the sliding assembly 4 only moves axially after entering the pressure-applying stage, avoiding unstable contact or signal fluctuations due to residual rotation. The third slide groove 15 is used to limit the movable position of the limiting member 41 on the pressure-applying portion; before the rotating member 42 contacts the limiting member 41, the limiting member 41 is fixed at the bottom end of the third slide groove 15; after the rotating member 42 contacts the limiting member 41, the rotating member 42 pushes the limiting member 41 to move on the third slide groove 15.

[0039] See also Figure 6 , further, regarding the connection and locking mechanism between the limiting member 41 and the rotating member 42:

[0040] The limiting member 41 and the rotating member 42 are provided with mutually compatible card slots 45 and buckles 46; before the rotating member 42 and the limiting member 41 come into contact, only the elastic force of the second spring 43 is transmitted to the needle 2 through the rotating member 42; after the rotating member 42 and the limiting member 41 come into contact, the card slot 45 and the buckle 46 are engaged to form a stable connection structure, and only the elastic force of the first spring 3 is transmitted to the needle 2 through the sliding assembly 4. A pushing member 47 is provided on the side wall of the needle tube 1. The pushing member 47 passes through the inner and outer sides of the needle tube 1. The pushing member 47 can move in the radial direction of the needle tube 1. A third spring is provided between the pushing member 47 and the needle tube 1. The third spring makes the pushing member 47 protrude outside the needle tube 1. The pushing member 47 acts on the card slot 45 and the buckle 46; when the card slot 45 and the buckle 46 are engaged, the pushing member 47 is pushed inward so that the pushing member 47 acts on the card slot 45 and the buckle 46, so that the card slot 45 and the buckle 46 are released from the buckled state, thereby realizing the separation of the rotating member 42 and the limiting member 41.

[0041] Rotating member 42 has not yet contacted stopper 41; sliding assembly 4 is only supported by second spring 43. The force of second spring 43 is transmitted to needle 2 via rotating member 42, enabling the rotary cleaning function. The pressure at this stage is low, preventing damage to the metal surface. Rotating member 42 contacts stopper 41, and slot 45 and latch 46 automatically engage. At this point, first spring 3 becomes the primary source of the force, with the force path passing through first spring 3, rotating member 42, stopper 41, and needle 2. This provides stronger axial pressure, ensuring a stable electrical connection between needle 2 and the test surface, while also preventing poor contact due to external vibration or pressure fluctuations.

[0042] After the test is completed, the sliding assembly 4 is still in the "slot 45-catch 46" locked state; if it needs to be reset at this time, the pushing member 47 can be pressed to push the inner end of the slot 45 and the catch 46 structure; thereby generating a relative displacement, so that the slot 45 and the catch 46 are disengaged; the rotating member 42 is separated from the limit member 41, and the sliding assembly 4 returns to the free state; under the joint action of the first spring 3 and the second spring 43, the needle 2 rebounds to the upper limit position; after completing a complete test cycle, the device is ready for the next round of testing.

[0043] However, after a complete test cycle, in order to restore the sliding assembly 4 to its initial state, the locking groove 45 and the buckle 46 structure between the rotating member 42 and the limit member 41 must be unlocked, otherwise the rotating member 42 will still be restricted by the limit member 41; the sliding assembly 4 cannot freely retreat to the upper limit position; during the resetting process, due to the spiral guiding characteristics of the first slide groove 13, the rotating member 42 may be forced to rotate in the opposite direction; this unexpected rotation action may cause the needle 2 to rub against the gold surface again during the process of leaving the test surface, causing unnecessary damage or residual marks.

[0044] See also Figure 7 To this end, this embodiment further introduces a fixing member 16-control member 17 linkage structure, and combines the slot 45-clip 46 locking mechanism and the push member 47 unlocking function to achieve active control of the movement path and state switching of the sliding component 4.

[0045] A fixing member 16 is provided in the third chute 15 to constrain the movement of the limiting member 41. A control member 17 connected to the fixing member 16 is provided in the first chute 13. Both the fixing member 16 and the control member 17 can slide in the radial direction of the needle tube 1. The fixing member 16 only restricts the upward movement of the limiting member 41 and does not restrict its downward movement or axial sliding. When the rotating member 42 slides in the first chute 13, it pushes the control member 17 to move radially of the needle tube 1 and drives the fixing member 16 to move. After the rotating member 42 contacts the limiting member 41, the control member 17 and the fixing member 16 move into place, and the upward movement restriction of the limiting member 41 by the fixing member 16 is released. A fourth spring is provided between the fixing member 16, the control member 17 and the needle tube 1 to push out the inner wall of the needle tube 1 between the fixing member 16, the control member 17 and the needle tube 1.

[0046] The non-marking spring test needle can be switched between a rotating operating state and a normal operating state:

[0047] Before the rotating member 42 contacts the limiting member 41, only the elastic force of the second spring 43 is transmitted to the needle 2 through the rotating member 42, and the elastic force of the first spring 3 acts on the third sliding groove 15 through the limiting member 41, but is not transmitted to the needle 2. The markless spring test needle is in a normal operating state.

[0048] After the rotating member 42 and the limiting member 41 come into contact, the locking groove 45 and the buckle 46 are engaged, and only the elastic force of the first spring 3 is transmitted to the needle 2 through the sliding assembly 4. After the locking groove 45 and the buckle 46 are engaged, the elastic force of the second spring 43 becomes the internal force of the sliding assembly 4 and does not act on the needle 2; the non-marking spring test needle is in a rotating operating state;

[0049] Before operation, the markless spring test needle is in a rotating operating state. During operation, the needle 2 destroys the surface of the test surface through circumferential rotation force. Then the markless spring test needle switches from the rotating operating state to the conventional operating state. After operation, the markless spring test needle is still in the conventional operating state to prevent the needle 2 from damaging the surface of the test surface again through circumferential rotation force.

[0050] Example 2

[0051] This embodiment discloses a method for seamless testing of a gold surface. The method is based on the seamless spring test needle structure described in the first embodiment and specifically includes the following steps:

[0052] S1. Initial preparation stage:

[0053] Place the electronic device to be tested on the test platform and ensure that its test surface is in a horizontal state; check whether the non-marking spring test needle is in a rotating operating state, that is, the slot 45 and the buckle 46 are engaged, and the sliding assembly 4 is locked; at this time, the first spring 3 provides the main elastic force for the needle 2 to ensure that the test needle has a stable initial contact ability; the front end of the needle 2 is designed to be arc-shaped to avoid local stress concentration on the gold surface.

[0054] S2, needle 2 contact and surface destruction stage:

[0055] Control the test equipment to slowly bring the test needle closer to the gold surface to be tested until the needle 2 lightly touches the test surface; continue to press the needle tube 1 downward, and the sliding component 4 begins to slide downward along the first slide groove 13 on the inner wall of the needle tube 1; since the first slide groove 13 is spirally distributed, it drives the rotating part 42 to produce circumferential rotational motion; the rotating part 42 transmits the rotational force to the needle 2, causing it to rotate slightly while obtaining axial pressure; the needle 2 contacts the gold surface in a "wiping" manner, effectively removing any oxide layer, stains or other insulating substances that may exist on the surface; the conical second spring 43 provides auxiliary elastic force at this stage to ensure that the pressure is moderate during the rotational cleaning process and does not damage the gold surface and the solder joint structure below.

[0056] S3, sliding component 4 switching and stable contact stage:

[0057] When the rotating member 42 continues to press down and enters the pressure-applying area, it disengages from the spiral guide path of the first slide groove 13; the rotating member 42 slides into the second slide groove 14, stops rotating, and only performs linear displacement; at this time, the rotating member 42 contacts the limit member 41, and the slot 45 and the buckle 46 automatically engage to form a mechanical connection; the first spring 3 becomes the main source of elastic force, and the elastic force path is: first spring 3 → rotating member 42 → limit member 41 → needle 2; the needle 2 establishes a reliable electrical connection with the test surface with stable axial pressure; this stage ensures the stability of current transmission, accurate signal acquisition, and improved test consistency and repeatability.

[0058] S4, test completion and reset stage

[0059] After the test is completed, the test system releases the pressing force, but the sliding assembly 4 is still in a locked state; if reset is required, the operator or automated equipment can push the pushing member 47 arranged on the side wall of the needle tube 1 inward; the pushing member 47 can move radially along the needle tube 1 under the action of the third spring, and its inner end acts on the slot 45 and the buckle 46 structure; the slot 45 and the buckle 46 are released, the rotating member 42 is separated from the limit member 41, and the sliding assembly 4 returns to a free state; under the joint action of the first spring 3 and the second spring 43, the sliding assembly 4 rebounds to the upper limit position, and the needle 2 is separated from the test surface; during the reset process, the sliding assembly 4 is no longer constrained by the limit member 41, avoiding unexpected rotation caused by the spiral slide guide; ensuring that the needle 2 does not cause secondary friction or damage to the gold surface during the separation process, truly realizing "traceless testing".

[0060] S5. State switching and retest preparation

[0061] After the reset is completed, the sliding assembly 4 enters the "normal operating state", that is, only the second spring 43 provides elastic force; the fixing member 16 re-locks the upward movement of the limit member 41 under the linkage of the control member 17; and prepares for the next test; ensuring that each test starts from the same initial state, improving the consistency and reliability of the test results.

[0062] Of course, the above are only typical examples of the present invention. In addition, the present invention may also have many other specific implementation methods. Any technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the present invention.

Claims

1. A non-marking spring test needle, comprising a needle tube, a needle head and a first spring, characterized in that: A first sliding groove is provided on the inner wall of the needle tube, a sliding assembly is provided in the first sliding groove, and the sliding assembly is located between the needle head and the first spring; The first slide groove extends in a spiral shape along the axis of the needle tube. When the needle contacts the test surface, the needle tube is pressed downward, and the sliding assembly slides relatively along the spiral first slide groove, and drives the needle to generate a rotational motion under the guidance of the first slide groove. The needle obtains axial pressure and circumferential rotational force at the same time, thereby effectively destroying the surface layer of the test surface, ensuring that the needle can accurately contact the substrate of the test surface, and achieving accuracy and consistency of the test results. The needle tube is divided into a rotating part and a pressure-applying part by the top end of the first chute; When the sliding assembly is located in the rotating part, the needle obtains axial pressure and circumferential rotational force at the same time, ensuring effective destruction of the surface layer of the test surface; when the sliding assembly is located in the pressure-applying part, the needle obtains axial pressure and ensures stable contact with the test surface.

2. The non-marking spring test needle according to claim 1, characterized in that: The sliding assembly includes a limiter, a rotating member, and a second spring. The limiter is located at the intersection of the rotating portion and the pressure-applying portion. The rotating member is slidably disposed in the first sliding groove. The second spring is disposed between the limiter and the rotating member. The connecting end of the second spring and the rotating member is rotatably connected. When the sliding assembly is located at the rotating part, the second spring provides axial pressure to the rotating member.

3. The non-marking spring test needle according to claim 2, characterized in that: The limiting member and the rotating member are both provided with guide slopes; the guide slopes cooperate with each other in structural design, so that the needle head obtains a more stable circumferential rotation force when it is in the rotating part; The second spring adopts a conical spring design; the conical spring can provide good axial pressure and radial support for the needle when the rotating part moves; at the same time, the conical spring has the characteristic of nonlinear elastic force change, thereby avoiding excessive damage to the surface of the test surface.

4. The non-marking spring test needle according to claim 2, characterized in that: A second chute and a third chute are provided on the inner wall of the needle tube, the bottom ends of the second chute and the third chute are both located at the intersection of the rotating part and the pressure-applying part, and the directions of the second chute and the third chute are parallel to the axis of the needle tube; The second sliding groove is connected to the first sliding groove, and the second sliding groove is used for limiting the movable position of the rotating member on the pressure portion; The third slide groove is used for limiting the activity of the limiting member on the pressure portion; before the rotating member contacts the limiting member, the limiting member is fixed at the bottom end of the third slide groove; after the rotating member contacts the limiting member, the rotating member pushes the limiting member to move on the third slide groove.

5. The non-marking spring test needle according to claim 4, characterized in that: The limiting member and the rotating member are provided with mutually adapted slots and buckles; Before the rotating member contacts the limiting member, only the elastic force of the second spring is transmitted to the needle through the rotating member; After the rotating member contacts the limiting member, the locking groove and the buckle are engaged with each other, and only the elastic force of the first spring is transmitted to the needle head through the sliding assembly.

6. The non-marking spring test needle according to claim 5, characterized in that: A pusher is provided on the side wall of the needle tube, and the pusher passes through the inner and outer sides of the needle tube. The pusher can move in the radial direction of the needle tube. A third spring is provided between the pusher and the needle tube, and the third spring makes the pusher protrude outside the needle tube. The pusher acts on the clamping slot and the buckle. When the slot and the buckle are engaged, the pushing member is pushed inward so that the pushing member acts on the slot and the buckle, so that the slot and the buckle are released from the engaged state, thereby realizing the separation of the rotating member and the limiting member.

7. The non-marking spring test needle according to claim 5 or 6, characterized in that: A fixing member is provided in the third chute to constrain the movement of the limiting member. A control member connected to the fixing member is provided in the first chute. Both the fixing member and the control member are capable of sliding in the radial direction of the needle tube. The fixing member only restricts the upward movement of the limiting member. When the rotating member slides in the first sliding groove, it pushes the control member to move in the radial direction of the needle tube and drives the fixed member to move; after the rotating member and the limiting member come into contact, the control member and the fixed member move into place, and the upward movement restriction of the limiting member by the fixed member is released.

8. The non-marking spring test needle according to claim 7, characterized in that: The non-marking spring test needle can be switched between a rotating operating state and a normal operating state; Before the rotating member contacts the limiting member, only the elastic force of the second spring is transmitted to the needle through the rotating member, and the non-marking spring test needle is in a normal operating state; After the rotating member and the limiting member come into contact, the locking groove and the buckle are engaged, and only the elastic force of the first spring is transmitted to the needle through the sliding assembly, and the markless spring test needle is in a rotating operation state; Before operation, the markless spring test needle is in a rotating operating state. During operation, the needle head destroys the surface of the test surface through circumferential rotational force. Then the markless spring test needle switches from the rotating operating state to the conventional operating state. After operation, the markless spring test needle is still in the conventional operating state to prevent the needle head from damaging the surface of the test surface again through circumferential rotational force.

9. A method for seamless testing of gold surfaces using the seamless spring test needle according to any one of claims 1 to 8.

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