Rolled U-shaped crimping terminal and preparation process thereof

Abstract

The invention discloses a rolled U-shaped crimping terminal and a preparation process thereof, and the preparation process comprises the following steps: selecting a continuous metal sheet of copper or copper alloy for cutting, carrying out fine rolling processing on a strip-shaped blank at a contact section position of the terminal, and forming two side cambered surfaces K at the contact section of the terminal by controlling process parameters in the fine rolling process, the foremost end of the contact section is subjected to cut-off face chamfering machining, a U-shaped cut-off face is formed, and the angle of the cut-off face is controlled to be smaller than 90 degrees so that inward inclination can be achieved; a leading-in area and a thinning transition area are formed between a contact section and a connection section of a terminal through processing, surface treatment and surface quality detection are performed on the terminal, a low-roughness contact surface is realized through a fine rolling technology, and the thickness of a crimping area 110, the diameter of a needle tip and angle parameters of each key area are accurately controlled, so that damage to a PCB coating is effectively reduced, and the service life of the PCB is prolonged. And the stability and the reliability of the connection between the terminal and the PCB are obviously improved.

Description

Technical Field

[0001] The invention relates to the technical field of terminals, and in particular to a rolled U-shaped crimping terminal and a preparation process thereof. Background Art

[0002] With the rapid development of electronic information technology and the trend of electronic products towards miniaturization, lightweight and high integration, crimp terminals, as key contact elements between electronic components and printed circuit boards (PCBs), are widely used in automotive electronics, consumer electronics, communication equipment and industrial automation. Terminals are not only required to have good conductivity, but also need to maintain reliable mechanical and electrical connection performance in high-density and miniaturized application environments. Therefore, how to balance production efficiency and cost control while ensuring low contact resistance and stable connection has become an important technical problem that needs to be solved in the current industry.

[0003] In the prior art, the preparation process of crimping terminals mostly adopts traditional stamping, forming and crimping methods. These processes often make it difficult to accurately control the surface roughness of the contact area between the terminal contact surface and the PCB coating during the processing, resulting in a relatively rough contact surface, which can easily cause scratches or wear on the PCB coating during the crimping process, thereby reducing the reliability and durability of the connection. In addition, traditional processes have limitations in the control of the geometry and angles of key areas such as the terminal arc surface and cut surface. For example, the chamfering and filleting are not sufficiently processed, and the ideal inclination and edge smoothing effects cannot be achieved. These defects not only reduce the elasticity and contact force of the crimping terminal, but also may cause problems such as poor contact and increased contact resistance during long-term use.

[0004] In view of this, it is necessary to improve the crimping terminals in the prior art to solve the technical problem of wear caused by insufficient precision. Summary of the invention

[0005] The object of the present invention is to provide a rolled U-shaped crimping terminal and a preparation process thereof, so as to solve the above technical problems.

[0006] To achieve this object, the present invention adopts the following technical solutions: A preparation process of a rolled U-shaped crimping terminal, comprising: Step S1, selecting a continuous metal sheet of copper or copper alloy and cutting it into strip blanks that meet the terminal size requirements; Step S2, performing finish rolling on the strip blank at the contact section of the terminal, and forming arc surfaces K on both sides of the terminal contact section by controlling process parameters during the finish rolling process, so that the surface roughness of the rolled surface is ≤0.8 μm, and a terminal with a U-shaped cross-section is formed, the thickness of the crimping area is controlled within 0.10 to 0.50 mm, and the terminal needle tip diameter is ≤0.30 mm; Step S3, performing chamfering processing on the front end of the contact segment to form a U-shaped cut surface, wherein the angle of the cut surface is controlled to be less than 90° to achieve inward inclination; at the same time, performing chamfering processing on the edge of the cut surface to make the minimum chamfer radius reach R0.05mm; Step S4, forming a lead-in area and a thinning transition area between the contact section and the connecting section of the terminal, wherein the lead-in area is formed with a guide angle of ≤30°, the transition angle of the thinning transition area is ≤30°, and the length of the crimping area is controlled within 0.5-1.5 mm; Step S5, cleaning and deburring the terminals, performing surface treatment, and then inspecting the surface quality of the terminals, and sorting the terminals according to the quality inspection results.

[0007] Optionally, the step S1 specifically includes: S11, selecting a continuous metal sheet with good plasticity and electrical conductivity as a raw material, which may be copper or a copper alloy; S12, after the continuous metal sheet is selected, its surface needs to be inspected, and if there is surface contamination or an oxide layer on its surface, the surface is cleaned; S13, cutting the cleaned metal sheet into strip blanks that meet the terminal size requirements, and controlling the width and length errors of the metal sheet within ±0.1mm during cutting.

[0008] Optionally, after step S13, the following steps are further included: S14, after the cutting is completed, the blank size is checked to ensure that the length, width and thickness of each strip blank meet the design requirements; S15, lubricating the cut strip blank, wherein the lubricant for the lubricating treatment includes an oil-based lubricant or a water-based lubricant.

[0009] Optionally, the step S2 specifically includes: S21, clamping the obtained strip blank on a rolling machine, and using a positioning fixture to accurately align the predetermined contact section area of ​​the terminal with the rolling area; at the same time, presetting the spacing between the stations of the rolling machine and the center distance of the rollers; S22, select a finely polished rolling die, whose surface is specially hardened and polished to ensure that the surface roughness of the die is less than 0.5μm. According to the terminal design requirements, preset the arc curvature parameters of the rolling die so that the arc surface K formed on both sides has a consistent and uniform curvature; at the same time, set the roller gap so that the thickness of the terminal crimping area after rolling is controlled within the range of 0.10-0.50mm, and the needle tip forming diameter is ≤0.30mm; S23, before the finish rolling process, the strip billet is pre-treated, the pre-treatment includes temperature balancing and fine-tuning the centering, and an automatic centering device is used to detect the billet thickness and edge straightness; S24, starting the rolling machine to perform finish rolling processing on the pre-treated blank, and in the terminal contact section area, the arc surface K on both sides is formed by continuous multi-pass micro-thinning processing, and the U-shaped cross-section is formed by the rolling die design; Optionally, after step S24, the following steps may be further performed: S25, during the finishing rolling process, an online measurement system is configured to monitor key process parameters in real time, wherein the key process parameters include rolling pressure, rolling speed, material temperature and surface roughness after forming, and a feedback control system is used to automatically adjust the roller gap and feed speed; S26, after the rolling is completed, the terminal is subjected to directional cooling treatment, using air cooling or water mist cooling to quickly bring the terminal to room temperature; S27, after the rolling process is completed, the contact section arc surface, U-shaped section and needle tip size of the terminal are tested using a surface roughness measuring instrument and a thickness measuring instrument to ensure that all indicators meet the requirements of surface roughness ≤ 0.8μm, crimping area thickness 0.10~0.50mm, and needle tip diameter ≤ 0.30mm.

[0010] Optionally, the step S3 specifically includes: S31, before cutting off the front end of the contact section of the terminal, fix and position the terminal, and then use a laser measuring device to calibrate the position of the front end of the terminal to ensure that the chamfer processing position is accurate and the error does not exceed ±0.01mm; S32, use a CNC cutting machine to chamfer the front end of the terminal contact section. The chamfer angle is usually set between 85° and 89°, and the feed speed of the cutting process should be set at 0.05-0.1 mm / s; S33, after the chamfering process is completed, the surface quality of the chamfered area is tested using a surface roughness tester to ensure that the surface roughness does not exceed Ra0.8μm.

[0011] Optionally, after step S33, the following steps are further included: S34, after the chamfering process is completed, the cutting edge of the chamfer is rounded using a CNC milling machine or a rounding tool. The rounding radius should be controlled within R0.05mm. During the processing, the tool feed speed is usually set to 0.05-0.1mm / s; S35, after the chamfering and rounding are completed, the terminal is cooled, specifically, the temperature is rapidly reduced by air cooling or liquid cooling, and after cooling, an ultrasonic cleaning device is used to perform a deburring process; Optionally, the step S4 specifically includes: S41, firstly accurately positioning the terminal in the transition area between the contact section and the connecting section so that the transition area between the contact section and the connecting section is aligned with the forming mold; S42, use CNC punching machine or stamping equipment to process the lead-in area of ​​the terminal to ensure that the guide angle of the lead-in area is controlled within ≤30°; S43, after the lead-in area is formed, the thinning transition area between the terminal contact section and the connection section is continuously processed, the angle of the transition area is controlled to be ≤30°, and the processing of the thinning transition area adopts a multi-pass stepwise thinning technology, and the processing depth of each pass is controlled within 0.05 mm; S44, after the processing of the lead-in area and the thinning transition area is completed, the length of the crimping area is controlled. According to the design requirements, the length of the crimping area should be maintained between 0.5 and 1.5 mm; specifically, a laser measuring device is used to perform real-time detection of the crimping area, and the feed amount and processing speed of the forming mold are adjusted.

[0012] Optionally, after step S44, the following steps may be further performed: S45, after processing, use a digital microscope to inspect the quality of the lead-in area, transition area and crimping area to ensure that the angle and size of each area meet the design requirements; S46, after the processing of the lead-in area, transition area and crimping area is completed, a directional cooling treatment is performed, specifically, liquid cooling or air cooling is used to quickly cool the processed terminals, and after cooling, ultrasonic cleaning equipment is used to remove impurities.

[0013] Compared with the prior art, the present invention has the following beneficial effects: firstly, a continuous metal sheet of copper or copper alloy is selected and cut into a strip blank that meets the terminal size requirements; through fine rolling, two side arc surfaces K are formed at the terminal contact section position; the surface roughness of the rolled surface is ≤0.8 μm; and the terminal cross section is ensured to be U-shaped, the thickness of the crimping area is 0.10-0.50 mm, and the terminal needle tip diameter is ≤0.30 mm; then, the front end of the contact section is chamfered and rounded to form an inward-inclined U-shaped cut surface, further reducing sharp edges and avoiding damage to the PCB plating layer; the contact section and the connecting section of the terminal are processed to form an introduction area and The transition zone is thinned to ensure that the guide angle of the introduction zone is ≤30°, the angle of the transition zone is ≤30°, and the length of the crimping zone is between 0.5 and 1.5 mm, ensuring that the terminal structure has good elasticity and contact force. The terminals are cleaned and deburred, and surface quality inspection is performed. Sorting is performed according to the inspection results to ensure that the products meet quality standards. The preparation process of the roll-formed U-shaped crimping terminal proposed in the present invention realizes a low-roughness contact surface through fine rolling technology, accurately controls the thickness of the crimping zone, the needle tip diameter and the angle parameters of each key area, thereby effectively reducing the damage to the PCB coating and significantly improving the stability and reliability of the connection between the terminal and the PCB. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0015] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with this technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantive technical significance. Any structural modification, change in proportion or adjustment of size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical contents disclosed by the present invention.

[0016] Figure 1 This is one of the schematic flow diagrams of the preparation process of the roll-formed U-shaped crimping terminal of this embodiment; Figure 2 The second schematic diagram is a process flow diagram of a preparation process of a roll-formed U-shaped crimping terminal of the present embodiment; Figure 3 This is a schematic diagram of the overall structure of the rolled U-shaped crimping terminal of this embodiment; Figure 4It is a schematic diagram of a half-section structure of the rolled U-shaped crimping terminal of this embodiment; Figure 5 Schematic diagram of a cut surface 120 of a roll-formed U-shaped crimping terminal of this embodiment; Figure 6 It is a schematic diagram of the plug-in structure of the rolled U-shaped crimping terminal and the PCB of this embodiment. DETAILED DESCRIPTION

[0017] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] In the description of the present invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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. It should be noted that when a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a centrally arranged component at the same time.

[0019] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0020] Combination Figures 1 to 6 As shown, an embodiment of the present invention provides a preparation process of a rolled U-shaped crimping terminal, comprising: Step S1, selecting a continuous metal sheet of copper or copper alloy, and cutting it into strip blanks that meet the terminal size requirements, cutting a continuous metal sheet (such as copper or copper alloy) with good plasticity and conductivity into strip blanks that meet the terminal size requirements, to provide raw materials for subsequent forming processing.

[0021] Step S2, performing finish rolling on the strip blank at the contact section 100 of the terminal. During the finish rolling process, by controlling the process parameters, arc surfaces K on both sides are formed on the contact section 100 of the terminal, so that the surface roughness of the rolled surface is ≤0.8μm, and at the same time, a terminal with a U-shaped cross-section is formed, and the thickness of the crimping area 110 is controlled within 0.10-0.50mm, and the terminal needle tip diameter is ≤0.30mm.

[0022] Step S3, the cutting surface 120 of the front end 101 of the contact section 100 is chamfered to form a U-shaped cutting surface 120, and the angle of the cutting surface 120 is controlled to be less than 90° (negative angle) to achieve inward inclination; at the same time, the edge of the cutting surface 120 is rounded to make the minimum chamfer radius reach R0.05mm; thereby eliminating sharp edges and reducing damage to the PCB coating.

[0023] Step S4, forming a lead-in area 300 and a thinned transition area 400 between the contact section 100 and the connecting section 200 of the terminal, wherein the guide angle formed by the lead-in area 300 is ≤30°, the transition angle of the thinned transition area 400 is ≤30°, and the length of the crimping area 110 is controlled within 0.5 to 1.5 mm; ensuring that the terminal thickness transitions smoothly and has good elasticity to provide reliable contact force.

[0024] Step S5, cleaning and deburring the terminals, and then inspecting the surface quality of the terminals, and sorting the terminals according to the quality inspection results.

[0025] Ensure that the terminal surface is clean; during the processing, strictly control and ensure that the remaining thickness of the PCB plating is ≥20μm to maintain sufficient conductivity and wear resistance; inspect the key dimensions, surface roughness and forming quality of each area of ​​the terminal to ensure that the product meets the design requirements.

[0026] The working principle of the present invention is as follows: first, a continuous metal sheet of copper or copper alloy is selected and cut into a strip blank that meets the terminal size requirements. Through fine rolling, two side arc surfaces K are formed at the terminal contact section 100, and the surface roughness of the rolled surface is ≤0.8μm. It is ensured that the terminal cross section is U-shaped, the thickness of the crimping area 110 is 0.10-0.50mm, and the terminal needle tip diameter is ≤0.30mm; then, the front end 101 of the contact section 100 is chamfered and rounded to form an inward U-shaped cut surface 120, further reducing sharp edges and avoiding damage to the PCB plating. The lead-in area 3 is formed between the contact section 100 and the connecting section 200 of the terminal. 00 and thinning transition zone 400, ensuring that the guide angle of the introduction zone 300 is ≤30°, the angle of the transition zone is ≤30°, and the length of the crimping zone 110 is between 0.5 and 1.5 mm, ensuring that the terminal structure has good elasticity and contact force, the terminals are cleaned and deburred, and surface quality inspection is performed, and sorting is performed according to the inspection results to ensure that the products meet quality standards. The preparation process of the roll-formed U-shaped crimping terminal proposed in the present invention realizes a low-roughness contact surface through fine rolling technology, accurately controls the thickness of the crimping zone 110, the needle tip diameter and the angle parameters of each key area, thereby effectively reducing the damage to the PCB coating, and significantly improving the stability and reliability of the connection between the terminal and the PCB.

[0027] In this embodiment, it is specifically explained that step S1 specifically includes: S11, selecting a continuous metal sheet with good plasticity and electrical conductivity as a raw material, which may be copper or a copper alloy; The selected material should have properties suitable for subsequent plastic processing, and should have high conductivity, good corrosion resistance and weldability. Copper alloy materials (such as C1100 or C1020) are widely used in the manufacture of such terminals because of their excellent conductivity and strong plasticity, which can adapt to the requirements of precision molding process.

[0028] S12, after the continuous metal sheet is selected, its surface needs to be inspected, and if there is surface contamination or an oxide layer on its surface, the surface is cleaned; Ensure that there is no obvious oxidation, stains, scratches or other defects that affect the quality of subsequent processing. If surface contamination or oxide layer is found, it should be removed by chemical cleaning or mechanical cleaning to ensure that the material surface is clean and has good lubricity. Common cleaning methods include pickling or mechanical polishing to ensure that no undesirable surface defects are produced during subsequent processing.

[0029] S13, cutting the cleaned metal sheet into strip blanks that meet the terminal size requirements, and controlling the width and length errors of the metal sheet within ±0.1mm during cutting.

[0030] The cutting process should use precision cutting equipment to ensure cutting accuracy and surface flatness. When cutting, the width and length error of the metal sheet should be controlled within ±0.1mm to meet the dimensional requirements of the subsequent forming process. It is recommended to use laser cutting or precision stamping equipment for cutting to ensure smooth edges and no excessive heat-affected zone.

[0031] The thickness of the cut metal blank should be precisely controlled according to the terminal size requirements. Generally, the thickness of the metal sheet used should be between 0.1mm and 0.5mm, and the specific value is determined according to the thickness of the crimping area 110 of the terminal design. To ensure the smooth progress of the subsequent rolling process, the error of the metal sheet thickness should be controlled within ±0.02mm to avoid affecting the crimping effect. If the thickness of the selected material is not suitable, preliminary thickness adjustment should be carried out by rolling or calendering.

[0032] S14, after the cutting is completed, the blank size is checked to ensure that the length, width and thickness of each strip blank meet the design requirements; The key to this step is to strictly control the dimensional accuracy to prevent process defects caused by dimensional errors in subsequent processing. At this time, high-precision measuring equipment (such as laser rangefinders or digital calipers) can be used for detection to ensure that the error is within the specified tolerance range.

[0033] S15, it is recommended to lubricate the cut strip blank, and the lubricant for the lubrication treatment includes an oil-based lubricant or a water-based lubricant.

[0034] In order to reduce the friction between the metal and the equipment during the subsequent processing and prevent the metal surface from being damaged due to excessive friction, it is recommended to lubricate the cut metal blank. Common lubricants include oil-based lubricants or water-based lubricants. The choice of lubricants should be reasonably matched according to the type of metal material and the processing requirements. The lubricating layer should be evenly distributed to avoid poor processing due to too much or too little lubricant.

[0035] In this embodiment, it is specifically described that step S2 specifically includes: S21, clamping the obtained strip blank on a rolling machine, and using a positioning fixture to accurately align the predetermined contact section 100 area of ​​the terminal with the rolling area; at the same time, presetting the station spacing of the rolling machine and the center distance of the rollers; Ensure that the thickness reduction and curved surface forming can be accurately achieved in the subsequent processing. In this preset step, a laser positioning device can be used to assist, and the positioning accuracy is controlled within ±0.01mm.

[0036] S22, select a finely polished rolling die, whose surface is specially hardened and polished to ensure that the surface roughness of the die is less than 0.5μm. According to the terminal design requirements, preset the arc curvature parameters of the rolling die so that the arc surface K formed on both sides has a consistent and uniform curvature; at the same time, set the roller gap so that the thickness of the terminal crimping area 110 after rolling is controlled within the range of 0.10 to 0.50mm, and the needle tip forming diameter is ≤0.30mm; This helps control the roughness transferred to the rolled surface of the terminal within 0.8 μm or less.

[0037] S23, before the finish rolling process, the strip billet is pre-treated, the pre-treatment includes temperature balancing and fine-tuning the centering, and an automatic centering device is used to detect the billet thickness and edge straightness; The automatic centering device is used to detect the thickness and edge straightness of the billet, so that the billet is evenly stressed during the rolling process to prevent local thinness or local residual stress. This correction step helps to ensure that the U-shaped section and arc surface K formed in the subsequent forming process meet the design requirements.

[0038] S24, starting the rolling machine to perform finish rolling processing on the pre-treated blank, in the terminal contact section 100 area, through continuous multi-pass micro-thinning processing, the arc surface K on both sides is formed, and the U-shaped cross-section is formed by the rolling die design; The roller pressure, rolling speed and feed rate are strictly controlled in each rolling process to ensure that the terminal surface gradually reaches the low roughness requirement (≤0.8μm) during multiple rolling processes; at the same time, the U-shaped cross-section is formed through the rolling die design to ensure that the thickness of the crimping area 110 is maintained within 0.10~0.50mm, and the terminal needle tip diameter is accurately controlled within the range of ≤0.30mm.

[0039] S25, during the finishing rolling process, an online measurement system is configured to monitor key process parameters in real time, including rolling pressure, rolling speed, material temperature and surface roughness after forming, and a feedback control system is used to automatically adjust the roller gap and feed speed; In order to correct the deviation in real time during the rolling process, it is ensured that each batch of products meets the predetermined technical parameters. This innovative measure can effectively improve the forming accuracy and stabilize the U-shaped cross-section and needle tip size.

[0040] S26, after the rolling is completed, the terminal is subjected to directional cooling treatment, using air cooling or water mist cooling to quickly bring the terminal to room temperature; This prevents internal stress concentration or dimensional deformation caused by uneven temperature. During the cooling process, the ambient temperature and humidity are kept stable to ensure the long-term stability of the shape and size of the finished product after rolling.

[0041] S27, after the rolling process is completed, the arc surface, U-shaped section and needle tip size of the contact section 100 of the terminal are tested using a surface roughness measuring instrument and a thickness measuring instrument to ensure that all indicators meet the requirements of surface roughness ≤ 0.8μm, crimping area 110 thickness between 0.10 and 0.50mm, and needle tip diameter ≤ 0.30mm.

[0042] The test data is uploaded to the industrial control system in real time to form a complete process data file, providing a basis for subsequent quality traceability and process optimization.

[0043] In this embodiment, it is specifically described that step S3 specifically includes: S31, before cutting off the front end 101 of the contact section 100 of the terminal, the terminal is fixed and positioned, and then the position of the front end 101 of the terminal is calibrated using a laser measuring device to ensure that the chamfer processing position is accurate and the error does not exceed ±0.01 mm; A high-precision fixture is used to firmly fix the terminal to ensure its stability during the chamfering process. At this time, a laser measuring device is used to accurately calibrate the position of the front end 101 of the terminal to ensure that the chamfering position is accurate and the error does not exceed ±0.01mm. After positioning, the feed speed and tool angle of the cutting machine are set to ensure the subsequent processing accuracy.

[0044] S32, using a CNC cutting machine to perform chamfering on the front end 101 of the terminal contact section 100, wherein the chamfering angle is usually set between 85° and 89°, and the feed speed of the cutting process should be set at 0.05-0.1 mm / s; The key to this process is to control the feed speed and cutting angle of the tool. The chamfer angle should be precisely controlled to less than 90°, and the tool should have high hardness and wear resistance to ensure stability during processing. The chamfer angle is usually set between 85° and 89°, depending on the structure and application requirements of the terminal. The feed speed of the cutting process should be set at 0.05-0.1mm / s to ensure a smooth cutting surface and not cause overheating of the material.

[0045] S33, after the chamfering process is completed, the surface quality of the chamfered area is tested using a surface roughness tester to ensure that the surface roughness does not exceed Ra0.8μm.

[0046] The roughness of the cut surface is strictly controlled to avoid burrs or rough cutting marks on the surface. In addition, the chamfered surface is lightly polished using special tools to ensure that the chamfered surface is smooth and burr-free, thereby further reducing the risk of damage to the PCB coating.

[0047] S34, after the chamfering process is completed, the cutting edge of the chamfer is rounded using a CNC milling machine or a rounding tool. The rounding radius should be controlled within R0.05mm. During the processing, the tool feed speed is usually set to 0.05-0.1mm / s; Avoid sharp edges from scratching the PCB coating. The fillet tool should be kept sharp to ensure stable cutting quality during processing. During processing, the tool feed speed is usually set to 0.05-0.1mm / s to ensure uniform fillet radius.

[0048] S35, after the chamfering and rounding are completed, the terminal is cooled, specifically, the temperature is rapidly reduced by air cooling or liquid cooling, and after cooling, an ultrasonic cleaning device is used to perform a deburring process; Cooling treatment is used to avoid dimensional deviation caused by heat accumulation. Air cooling or liquid cooling is used to quickly cool down to ensure the stability of the terminal shape. After cooling, ultrasonic cleaning equipment is used to deburr and remove the tiny burrs that may be generated during cutting and rounding to ensure the cleanliness of the terminal surface and avoid affecting the subsequent crimping effect.

[0049] Each terminal shall be strictly inspected for size and quality after chamfering and filleting. A high-precision digital microscope shall be used to inspect the angle of the chamfer to ensure that it is less than 90° and the error does not exceed ±1°. In addition, a surface roughness tester shall be used to inspect the chamfer surface and fillet edge to ensure that the roughness meets the requirement of Ra0.8μm and that the fillet radius reaches R0.05mm. All inspection data shall be recorded and archived in real time for easy traceability and quality control.

[0050] In this embodiment, it is specifically described that step S4 specifically includes: S41, firstly accurately positioning the terminal in the transition area between the contact section 100 and the connecting section 200, so that the transition area between the contact section 100 and the connecting section 200 is aligned with the molding die; During the forming process, laser is used to position the terminal as a whole and ensure that the processing position and accuracy of the lead-in area 300 and the thinned transition area 400 meet the design requirements. The goal of this step is to ensure that the lead-in area 300 and the thinned transition area 400 can transition smoothly without material defects.

[0051] S42, using a CNC punching machine or a stamping device to process the lead-in area 300 of the terminal to ensure that the guide angle of the lead-in area 300 is controlled within ≤30°; The processing of the lead-in area 300 should ensure that the metal material does not produce cracks or other defects during the deformation process. The stamping speed and pressure should be strictly controlled during operation to avoid excessive compression or stretching of the material due to excessive pressure. Usually, the stamping pressure is 10-20 tons, and the feed speed is controlled within the range of 0.05-0.1mm / s.

[0052] S43, after the lead-in area 300 is formed, the thinning transition area 400 between the terminal contact section 100 and the connecting section 200 is processed, the angle of the transition area is controlled to be ≤30°, and the processing of the thinning transition area 400 adopts a multi-pass stepwise thinning technology, and the processing depth of each pass is controlled within 0.05 mm; To ensure that the contact force between the terminal and the PCB plated hole is evenly distributed, and to avoid poor contact caused by excessive contact force. The processing of the thinning transition zone 400 adopts multi-pass gradual thinning technology to gradually reduce the thickness of the transition zone to ensure a smooth transition of the overall thickness. The processing depth of each pass should be controlled within 0.05mm to avoid excessive deformation of the material.

[0053] S44, after the processing of the introduction area 300 and the thinning transition area 400 is completed, the length of the crimping area 110 is controlled. According to the design requirements, the length of the crimping area 110 should be maintained between 0.5 and 1.5 mm; specifically, a laser measuring device is used to perform real-time detection of the crimping area 110, and the feed amount and processing speed of the forming mold are adjusted.

[0054] This step uses laser measurement equipment to perform real-time detection of the crimping area 110, and adjusts the feed rate and processing speed of the forming die to ensure that the length of the crimping area 110 of each terminal is accurate. During the processing, the equipment should maintain a constant speed and pressure to avoid the length error of the crimping area 110 caused by speed changes.

[0055] S45, after the processing is completed, a digital microscope is used to perform quality inspection on the lead-in area 300, the transition area and the crimping area 110 to ensure that the angle and size of each area meet the design requirements; In particular, digital measuring instruments are used to detect the guide angle of the lead-in area 300, the angle of the transition area, and the length of the crimping area 110 to ensure that their errors are controlled within ±0.01 mm. The dimensional data of each batch of products should be recorded and archived in real time to provide guarantee for quality traceability.

[0056] To ensure high precision during the processing, a real-time feedback system and intelligent detection platform are used to dynamically monitor the forming conditions of the lead-in area 300 and the transition area. Through sensors, photoelectric measuring devices and data analysis systems, small errors that occur during the forming process are automatically compensated. The innovative feedback system can adjust the stamping pressure, feed speed and processing die gap in real time to maintain the stability of various process parameters and ensure the consistency of product quality.

[0057] S46, after the processing of the introduction area 300, the transition area and the crimping area 110 is completed, a directional cooling treatment is performed, specifically using liquid cooling or air cooling to quickly cool the processed terminals. After cooling, ultrasonic cleaning equipment is used to remove impurities.

[0058] To reduce the internal stress generated during the processing. Liquid cooling or air cooling is used to quickly cool the processed terminals to avoid deformation of the terminal shape or inaccurate size due to excessive temperature difference. After cooling, ultrasonic cleaning equipment is used to remove the residues and impurities generated during the processing to ensure the cleanliness and high quality of the terminals.

[0059] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A process for preparing a rolled U-shaped crimping terminal, characterized in that: include: Step S1, selecting a continuous metal sheet of copper or copper alloy and cutting it into strip blanks that meet the terminal size requirements; Step S2, performing finish rolling on the strip blank at the contact section of the terminal, and forming arc surfaces K on both sides of the terminal contact section by controlling process parameters during the finish rolling process, so that the surface roughness of the rolled surface is ≤0.8 μm, and a terminal with a U-shaped cross-section is formed, the thickness of the crimping area is controlled within 0.10 to 0.50 mm, and the terminal needle tip diameter is ≤0.30 mm; Step S3, performing chamfering processing on the front end of the contact segment to form a U-shaped cut surface, wherein the angle of the cut surface is controlled to be less than 90° to achieve inward inclination; at the same time, performing chamfering processing on the edge of the cut surface to make the minimum chamfer radius reach R0.05mm; Step S4, forming a lead-in area and a thinning transition area between the contact section and the connecting section of the terminal, wherein the lead-in area is formed with a guide angle of ≤30°, the transition angle of the thinning transition area is ≤30°, and the length of the crimping area is controlled within 0.5-1.5 mm; Step S5, cleaning and deburring the terminals, performing surface treatment, and then inspecting the surface quality of the terminals, and sorting the terminals according to the quality inspection results.

2. The process for preparing the roll-formed U-shaped crimping terminal according to claim 1, characterized in that: The step S1 specifically includes: S11, selecting a continuous metal sheet with good plasticity and electrical conductivity as a raw material, which may be copper or a copper alloy; S12, after the continuous metal sheet is selected, its surface needs to be inspected, and if there is surface contamination or an oxide layer on its surface, the surface is cleaned; S13, cutting the cleaned metal sheet into strip blanks that meet the terminal size requirements, and controlling the width and length errors of the metal sheet within ±0.1mm during cutting.

3. The process for preparing the roll-formed U-shaped crimping terminal according to claim 2, characterized in that: After step S13, the following steps are also included: S14, after the cutting is completed, the blank size is checked to ensure that the length, width and thickness of each strip blank meet the design requirements; S15, lubricating the cut strip blank, wherein the lubricant for the lubricating treatment includes an oil-based lubricant or a water-based lubricant.

4. The process for preparing the roll-formed U-shaped crimping terminal according to claim 1, characterized in that: The step S2 specifically includes: S21, clamping the obtained strip blank on a rolling machine, and using a positioning fixture to accurately align the predetermined contact section area of ​​the terminal with the rolling area; at the same time, presetting the spacing between the stations of the rolling machine and the center distance of the rollers; S22, select a finely polished rolling die, whose surface is specially hardened and polished to ensure that the surface roughness of the die is less than 0.5μm. According to the terminal design requirements, preset the arc curvature parameters of the rolling die so that the arc surface K formed on both sides has a consistent and uniform curvature; at the same time, set the roller gap so that the thickness of the terminal crimping area after rolling is controlled within the range of 0.10-0.50mm, and the needle tip forming diameter is ≤0.30mm; S23, before the finish rolling process, the strip billet is pre-treated, the pre-treatment includes temperature balancing and fine-tuning the centering, and an automatic centering device is used to detect the billet thickness and edge straightness; S24, start the rolling machine to perform finish rolling on the pre-treated blank. In the terminal contact section area, the arc surface K on both sides is formed by continuous multi-pass micro-thinning processing, and the U-shaped cross-section is formed by the rolling die design.

5. The process for preparing the roll-formed U-shaped crimping terminal according to claim 4, characterized in that: After step S24, the following steps are also included: S25, during the finishing rolling process, an online measurement system is configured to monitor key process parameters in real time, wherein the key process parameters include rolling pressure, rolling speed, material temperature and surface roughness after forming, and a feedback control system is used to automatically adjust the roller gap and feed speed; S26, after the rolling is completed, the terminal is subjected to directional cooling treatment, using air cooling or water mist cooling to quickly bring the terminal to room temperature; S27, after the rolling process is completed, the contact section arc surface, U-shaped section and needle tip size of the terminal are tested using a surface roughness measuring instrument and a thickness measuring instrument to ensure that all indicators meet the requirements of surface roughness ≤ 0.8μm, crimping area thickness 0.10~0.50mm, and needle tip diameter ≤ 0.30mm.

6. The process for preparing the roll-formed U-shaped crimping terminal according to claim 1, characterized in that: The step S3 specifically includes: S31, before cutting off the front end of the contact section of the terminal, fix and position the terminal, and then use a laser measuring device to calibrate the position of the front end of the terminal to ensure that the chamfer processing position is accurate and the error does not exceed ±0.01mm; S32, use a CNC cutting machine to chamfer the front end of the terminal contact section. The chamfer angle is usually set between 85° and 89°, and the feed speed of the cutting process should be set at 0.05-0.1 mm / s; S33, after the chamfering process is completed, the surface quality of the chamfered area is tested using a surface roughness tester to ensure that the surface roughness does not exceed Ra0.8μm.

7. The process for preparing the roll-formed U-shaped crimping terminal according to claim 6, characterized in that: After step S33, the following steps are also included: S34, after the chamfering process is completed, the cutting edge of the chamfer is rounded using a CNC milling machine or a rounding tool. The rounding radius should be controlled within R0.05mm. During the processing, the tool feed speed is usually set to 0.05-0.1mm / s; S35, after the chamfering and rounding are completed, the terminal is cooled, specifically, the temperature is rapidly reduced by air cooling or liquid cooling, and after cooling, the terminal is deburred by using ultrasonic cleaning equipment.

8. The process for preparing the roll-formed U-shaped crimping terminal according to claim 1, characterized in that: The step S4 specifically includes: S41, firstly accurately positioning the terminal in the transition area between the contact section and the connecting section so that the transition area between the contact section and the connecting section is aligned with the forming mold; S42, use CNC punching machine or stamping equipment to process the lead-in area of ​​the terminal to ensure that the guide angle of the lead-in area is controlled within ≤30°; S43, after the lead-in area is formed, the thinning transition area between the terminal contact section and the connection section is continuously processed, the angle of the transition area is controlled to be ≤30°, and the processing of the thinning transition area adopts a multi-pass stepwise thinning technology, and the processing depth of each pass is controlled within 0.05 mm; S44, after the processing of the lead-in area and the thinning transition area is completed, the length of the crimping area is controlled. According to the design requirements, the length of the crimping area should be maintained between 0.5 and 1.5 mm; specifically, a laser measuring device is used to perform real-time detection of the crimping area, and the feed amount and processing speed of the forming mold are adjusted.

9. The process for preparing the roll-formed U-shaped crimping terminal according to claim 8, characterized in that: After step S44, the following steps are also included: S45, after processing, use a digital microscope to inspect the quality of the lead-in area, transition area and crimping area to ensure that the angle and size of each area meet the design requirements; S46, after the processing of the lead-in area, transition area and crimping area is completed, a directional cooling treatment is performed, specifically, liquid cooling or air cooling is used to quickly cool the processed terminals, and after cooling, ultrasonic cleaning equipment is used to remove impurities.

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