Preparation method of high and low frequency composite micro rectangular connector

Abstract

The invention discloses a preparation method of a high and low frequency composite micro rectangular connector, the micro rectangular connector mainly comprises a porous metal shell, a plurality of metal inner conductors, a low frequency glass insulator and a high frequency glass insulator, the glass insulator is arranged in a sealing hole of the metal shell, and the metal inner conductors are arranged in the glass insulator in a penetrating manner; the upper end face and the lower end face of each metal inner conductor are flush. The preparation method mainly comprises the steps of mold design, pretreatment, assembly, primary sintering, primary cleaning, secondary sintering, secondary cleaning, tertiary sintering and tertiary cleaning. The product obtained by the preparation method provided by the invention has the advantages of flat high and low frequency end surfaces, uniform glass surface, consistent inner conductor height and no eccentric problem, the problem of high sintering difficulty of the product is solved, and meanwhile, the yield of the high and low frequency composite product is increased from 20% to 85%.

Description

Technical Field

[0001] The invention relates to the technical field of glass sealing, and in particular to a method for preparing a high-low frequency composite micro rectangular connector. Background Art

[0002] According to the frequency of signal transmission, it is divided into high-frequency connector and low-frequency connector. High-frequency connector is a single-core glass insulator, and low-frequency connector is a multi-core glass insulator, which is commonly 25-core, 37-core, etc.; according to the spacing of the inner conductor, it is divided into J63 series, J30 series, etc. Usually, high-frequency and low-frequency connectors are two independent parts. In some special applications, they need to be used in combination, that is, one connector contains both high-frequency and low-frequency parts, forming a new type of micro-rectangular connector. Due to the different materials of glass insulators used for high and low frequencies, in order to ensure the consistency of glass height and inner conductor height of the high and low frequency parts of the connector, and reduce defects such as glass bubbles, glass cracks, and impurities, a specific sintering process is required to ensure the consistency and quality of the product. At the same time, the sealing depth of the high-frequency part of this type of composite micro-rectangular connector is usually greater than 2.5mm. Limited by the current technical limitations of domestic glass insulators, two sections of glass need to be sintered. Cavities and pores are prone to exist inside the product, which greatly increases the possibility of bubble defects, resulting in product performance failure, and further increases the difficulty of sintering such products. Therefore, a specific sintering process to solve the problem of low first-time yield of such products has become the focus of most attention at present. Summary of the invention

[0003] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method for preparing a high- and low-frequency composite micro-rectangular connector. By improving the sintering mold structure, the problems of product eccentricity and core column bending can be basically avoided, and the problem of graphite sticking due to the good fluidity of the glass surface can be avoided; by controlling the sintering temperature, the uniformity of the high- and low-frequency glass surfaces can be ensured, and the problems of high-frequency glass surface inclination and internal cavity can be avoided, thereby improving the yield of such products; the high- and low-frequency composite micro-rectangular connector products finally prepared have high dimensional accuracy, good yield, and low cost, and meet the requirements of mass production of enterprises.

[0004] The technical solution adopted by the present invention to solve the technical problem is: a preparation method of a high-low frequency composite micro rectangular connector, characterized in that: the micro rectangular connector mainly includes a metal shell, a plurality of metal inner conductors and a glass insulator, the metal shell includes a high-frequency connector part and a low-frequency connector part; in the high-frequency connector part, the high-frequency glass insulator is arranged in the circular hole of the metal shell, and the high-frequency metal inner conductor is passed through a single circular hole of the high-frequency glass insulator; in the low-frequency connector part, the low-frequency glass insulator is arranged in the low-frequency hole, and the low-frequency metal inner conductor is passed through multiple circular holes of the low-frequency glass insulator; the upper end faces and lower end faces of the high-frequency and low-frequency metal inner conductors are both flush, and the glass surfaces are both flush after sintering;

[0005] The method for preparing the micro rectangular connector comprises the following steps:

[0006] 1) Mold design: the high-frequency connector part and the low-frequency connector part are designed as a split assembly mode. The graphite mold includes a graphite lower mold, a graphite upper mold 1 and a graphite upper mold 2. The graphite lower mold and the graphite upper mold 1 are respectively provided with an upper multi-porous position and a lower multi-porous position, and the graphite upper mold 2 is provided with an upper single-hole position;

[0007] 2) Degreasing and cleaning the metal shell, each metal inner conductor, and the graphite mold, and after sintering in a furnace, pre-oxidizing the metal shell and each metal inner conductor;

[0008] 3) Assemble the pre-oxidized metal shell, high-frequency and low-frequency metal inner conductors, and high-frequency and low-frequency glass insulators in a graphite mold; the graphite mold includes a graphite lower mold and a graphite upper mold, and the metal shell is arranged between the graphite upper mold and the graphite lower mold; the low-frequency glass insulator is arranged in the low-frequency hole of the metal shell, and each low-frequency metal inner conductor passes through the lower porous position of the graphite lower mold, the porous position of the low-frequency glass insulator, and the upper porous position of the graphite upper mold, and then a certain weight of stainless steel sheet is covered on the graphite upper mold;

[0009] 4) placing the assembled sintered parts into a chain atmosphere furnace at a certain temperature for a sintering process. After the sintering process is completed, taking out and disassembling the mold to obtain the low-frequency micro rectangular connector to be processed;

[0010] 5) Soak the low-frequency micro-rectangular connector to be processed in a concentrated hydrofluoric acid solution for pickling for a certain period of time until the glass surface of the product shows obvious fish scale corrosion marks when observed under a microscope at 25 times, and the height of the glass surface is slightly higher than the metal shell, and then dry it;

[0011] 6) The pickled low-frequency micro-rectangular connector is subjected to secondary pre-oxidation treatment at a certain temperature and secondary assembly with a graphite mold; the graphite mold comprises a graphite lower mold, a graphite upper mold 1 and a graphite upper mold 2, and the pickled low-frequency micro-rectangular connector is arranged between the graphite upper mold and the graphite lower mold; the high-frequency glass insulator is arranged in a single circular hole of the metal shell, and the high-frequency metal inner conductor passes through the single hole position of the graphite lower mold, the single hole position of the high-frequency glass insulator and the single hole position of the graphite upper mold 2, and the graphite upper mold 1 is placed at the same time, and finally a certain weight of stainless steel sheet is covered on the graphite upper mold 1 and the graphite upper mold 2; it is placed in a chain atmosphere furnace at a certain temperature for secondary sintering, and after the sintering is completed, the mold is taken out and disassembled to obtain a micro-rectangular connector to be processed;

[0012] 7) Mechanically grind the side end face and the upper end face of the metal shell of the composite micro rectangular connector to be processed, and put it into a deburring machine for deburring treatment until the bonding end face of each metal inner conductor is smooth and flat without burrs, iron filings, and scratches;

[0013] 8) The deburred composite micro rectangular connector is immersed in a concentrated hydrofluoric acid solution for secondary pickling for a certain period of time until the height of the glass surface of the product does not exceed the surface of the metal shell when observed from the side, and then dried;

[0014] 9) Assemble the pickled composite micro rectangular connector again with the re-sintered graphite lower mold, the graphite upper mold 1 and the graphite upper mold 2, put it into a chain atmosphere furnace at a certain temperature for three sinterings, and after the sintering is completed, take out and disassemble the mold to obtain a semi-finished composite micro rectangular connector;

[0015] 10) The semi-finished micro-rectangular connector is immersed in a mixed acid solution for three acid washing treatments to remove graphite and impurities remaining in the sintering process, and finally the product is dried to obtain a finished composite micro-rectangular connector.

[0016] Furthermore, in step 2), the furnace sintering process is sintering in a chain sintering furnace at 920°C to 940°C; the degreasing process is ultrasonication in a saturated detergent solution for 10 to 20 minutes; and the pre-oxidation treatment process is at 650 to 680°C, 2L / min high-temperature humidified nitrogen atmosphere, and a belt speed of 50mm / min.

[0017] Furthermore, in step 3), the assembly order is graphite lower mold, metal shell, low-frequency glass insulator, low-frequency metal inner conductor, and graphite upper mold one; the overall glass hole gap is 0.635±0.05; the average weight of the stainless steel sheet covering each connector is 0.5~1g.

[0018] Further, in step 3), a first lower groove is provided on the graphite lower mold, a second lower groove is provided in the first lower groove, and a certain step surface is formed between the first lower groove and the second lower groove; a plurality of the lower porous positions are provided in the second lower groove; during assembly, the first lower groove is embedded with the outer edge of the metal shell; and the second lower groove is embedded with the outer edge of the low-frequency glass insulator.

[0019] Further, in step 3), the graphite lower mold matches the graphite upper mold 1 and the graphite upper mold 2; the graphite upper mold 1 and the graphite upper mold 2 are respectively provided with a graphite upper mold 1 boss and a graphite upper mold 2 boss, and the graphite upper mold 1 boss is provided with a plurality of the upper porous positions; during assembly, the boss is embedded in the inner cavity of the metal shell, and the upper porous position is inserted in cooperation with the low-frequency metal inner conductor.

[0020] Furthermore, the upper porous position of the graphite upper die 1 is a blind hole, the upper single hole position of the graphite upper die 2 is a blind hole, and the lower porous position of the graphite lower die is a blind hole.

[0021] Furthermore, in the composite micro-rectangular connector, the material of the metal shell and each metal inner conductor is Kovar alloy; the diameter of the high-frequency sealing hole of the metal shell is 1-1.2 mm, and the height is 3.0-4.5 mm; the diameter of the high-frequency metal inner conductor is 0.3-0.45 mm, and the length is 5.5-6.0 mm; the high-frequency glass insulator is BH-24G / K, with an outer diameter of 1.05-1.15 mm, an inner diameter of 0.45-0.55 mm, and a height of 1.7-2.0 mm; the low-frequency of the metal shell is a 25-37-core J63 or J30 micro-rectangular connector, and the low-frequency glass insulator is BH-G / K, with a height of 3.5-5.0 mm.

[0022] Furthermore, in step 4), the sintering process is 1000° C. to 1030° C., a belt speed of 35 to 45 mm / min, and a nitrogen atmosphere.

[0023] Further, in step 5), a pickling process is performed by placing the connector in a pickling tool and immersing it in a concentrated hydrofluoric acid solution until obvious fish scale corrosion marks appear on the glass surface of the product when observed under a microscope at 25 times. After the height of the glass surface is slightly higher than that of the shell, it is placed in a saturated NaCO3 solution for neutralization and ultrasonic treatment for 10 to 15 minutes, then replaced with 45°C hot water for ultrasonic treatment for 10 to 15 minutes, and finally immersed in a 60°C hot alcohol solution for 20 to 40 seconds and then dried.

[0024] Furthermore, in step 7), the secondary pickling process is to place the connector in a pickling tool, immerse it in a concentrated hydrofluoric acid solution for a certain period of time until the glass surface of the product is lower than the surface of the metal shell, put it into a saturated NaCO3 solution for neutralization and ultrasonic treatment for 10 to 15 minutes, then change to 45°C hot water ultrasonic treatment for 10 to 15 minutes, and finally immerse it in a 60°C hot alcohol solution for 20 to 40 seconds and then dry it.

[0025] Furthermore, in step 10), the three pickling processes are to place the connector in a pickling tool, immerse it in a mixed acid solution, wherein the volume ratio of water, hydrofluoric acid and hydrochloric acid is H2O:HF:HCl=17-19:1:1, and then put it into a saturated NaCO3 solution for neutralization and ultrasonication for 10-15 minutes, then replace it with 45°C hot water and ultrasonicate for 10-15 minutes, and finally immerse it in a 60°C hot alcohol solution for 20-40 seconds and then dry it.

[0026] The beneficial effects of the present invention are as follows: compared with the prior art, in the preparation method of the high- and low-frequency composite micro-rectangular connector provided by the present invention, the sealing hole depth of the high-frequency connector is ≥2.5mm, the glass surface of the product is uniform and flush after sintering, and there is no cavity or pore inside the product. The low-frequency connector is a J63 series, and the overall glass is sintered. The glass surface is uniform after sintering, and there is no cavity in the product. The high and low frequency glass heights of the overall product are uniform and consistent, and the inner conductor height consistency is <±0.03, and the one-time yield rate can reach 85%; the graphite molds used are divided into low The upper mold 1 is a graphite upper mold for high frequency, the upper mold 2 is a graphite upper mold for high frequency and the overall lower mold. The upper mold 1 and the lower mold are respectively provided with upper multi-hole positions and lower multi-hole positions, and the upper mold 2 is provided with an upper single hole position to ensure that the exposed dimensions of the upper and lower end surfaces of the high- and low-frequency inner conductors of the glass insulator are consistent after sintering. Since this type of product involves high-frequency and low-frequency products, the glass materials used are different and the expansion coefficients are different; and the sealing depth of the high-frequency part is deeper, two sections of the same glass blank need to be placed during the assembly process, but due to burrs and unevenness on the surface of the glass blank, there is a certain gap between the two sections of glass. The mold designed by this invention separates the upper mold and calculates the expansion coefficients of different components respectively, which can effectively avoid product eccentricity and core column bending caused by expansion; and the lower mold does not distinguish between new firing and re-firing. The lower mold is designed with the first lower groove and the second lower groove. When newly fired, the glass is guaranteed to increase by 0.3mm in height downward, which is conducive to ensuring the consistency of high-frequency glass flatness and reducing the risk of glass holes and glass subsidence; when re-firing, the gap between the small step and the glass is 0.3mm, ensuring that the exposed metal inner conductor meets the required size, avoiding the problem of poor insulation on the surface of the product glass due to graphite adhesion, and reducing costs. At the same time, it is necessary to select a suitable sintering temperature for both glass materials, and slightly increase the temperature to reduce the viscosity of the glass and enhance the fluidity of the glass. At high temperatures, the movement of gas molecules intensifies, which is conducive to the bubbles in the two sections of glass to gather from small bubbles to large bubbles and float up and discharge. By improving the sintering mold structure, the problems of product eccentricity and core column bending can be basically avoided, and the problem of graphite sticking due to the good fluidity of the glass surface can be avoided; by controlling the sintering temperature, the uniformity of the high and low frequency glass surfaces can be guaranteed, and the problems of high frequency glass surface inclination and internal cavity can be avoided, which solves the problem of the difficulty of sintering such products, and at the same time increases the yield of such high and low frequency composite products from 20% to 85%; the prepared high and low frequency micro-rectangular connector products have high dimensional accuracy, good yield and low cost, which meet the requirements of mass production of enterprises. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic structural diagram of a graphite lower mold in the preparation method provided by the present invention.

[0028] Figure 2 A schematic diagram of the partial cross-sectional structure of the graphite lower mold provided by the present invention.

[0029] Figure 3The present invention provides a schematic diagram of the cross-sectional structure of a graphite upper mold 1 in the preparation method provided by the present invention.

[0030] Figure 4 This is a schematic diagram of the cross-sectional structure of the second graphite upper mold in the preparation method provided by the present invention.

[0031] Figure 5 This is a schematic diagram of the partial assembly structure of the high-low frequency composite micro rectangular connector provided by the present invention.

[0032] Among them, 1-graphite lower mold; 2-first lower groove; 3-second lower groove; 4-lower porous position; 5-graphite upper mold one boss; 6-upper porous position; 7-graphite upper mold two bosses; 8-upper single hole position; 9-metal shell; 10-low-frequency metal inner conductor; 11-low-frequency glass insulator; 12-high-frequency metal inner conductor; 13-high-frequency glass insulator. DETAILED DESCRIPTION

[0033] The present invention is further described below by specific examples, but these examples are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0034] Example

[0035] like Figures 1 to 5 As shown, a preparation method of a high-low frequency composite micro rectangular connector is characterized in that: the micro rectangular connector mainly includes a metal shell, a plurality of metal inner conductors and a glass insulator, the metal shell includes a high-frequency connector part and a low-frequency connector part; in the high-frequency connector part, the high-frequency glass insulator is arranged in the circular hole of the metal shell, and the high-frequency metal inner conductor is passed through a single circular hole of the high-frequency glass insulator; in the low-frequency connector part, the low-frequency glass insulator is arranged in the square low-frequency hole, and the low-frequency metal inner conductor is passed through multiple circular holes of the low-frequency glass insulator; the upper end face and the lower end face of the high-frequency and low-frequency metal inner conductors are flush, and the glass surface is flush; according to the requirements of the drawing, the graphite The lower mold 1 matches the graphite upper mold 1 and the graphite upper mold 2; the graphite upper mold 1 and the graphite upper mold 2 are respectively provided with a graphite upper mold 1 boss 5 and a graphite upper mold 2 boss 7, the graphite upper mold 1 boss 5 is provided with a plurality of upper multi-hole positions 6, and the graphite upper mold 2 boss 7 is provided with an upper single hole position 8; the graphite lower mold 1 is provided with a first lower groove 2, the first lower groove 2 is provided with a second lower groove 3, and a certain step surface is formed between the first lower groove 2 and the second lower groove 3; the second lower groove 3 is provided with a plurality of the lower multi-hole positions 4; during assembly, the first lower groove 2 is embedded with the outer edge of the metal shell 9; the second lower groove 3 is embedded with the outer edge of the low-frequency glass insulator 11.

[0036] The method for preparing the high-low frequency composite micro rectangular connector comprises the following steps:

[0037] 1) Degreasing and cleaning the metal shell 9, each metal inner conductor, and the graphite mold, and after furnace sintering, pre-oxidation treatment is performed on the metal shell 9 and each metal inner conductor; the furnace sintering process is sintering in a chain sintering furnace at 920°C to 940°C; the degreasing process is ultrasonic cleaning in a saturated NaCO3 solution for 15 minutes, and then ultrasonic cleaning in anhydrous ethanol for 15 minutes; the pre-oxidation treatment process is at 650 to 680°C, 2L / min high temperature humidified nitrogen atmosphere, and a belt speed of 50mm / min. The oxidation time is 1.5 hours;

[0038] 2) The pre-oxidized metal shell 9, each metal inner conductor and each glass insulator are assembled in a graphite mold; the assembly sequence is graphite lower mold 1, metal shell 9, low-frequency glass insulator 11, low-frequency metal inner conductor 10, and graphite upper mold 1; the outer edge of the metal shell 9 is matched with the first lower groove 2 of the graphite lower mold 1; the low-frequency glass insulator 11 is arranged in the square low-frequency hole of the metal shell 9, and the upper surface is matched with the second lower groove 3 of the graphite lower mold 1, and each low-frequency metal inner conductor 10 passes through the lower porous position 4 of the graphite lower mold and the porous position of the low-frequency glass insulator, and finally the upper porous position 6 of the graphite upper mold 1 passes through the low-frequency metal inner conductor 10, and after the graphite upper mold 1 boss 5 is matched with the edge of the square inner cavity of the metal shell 9, a whole piece of stainless steel sheet weighing about 20g is covered on the top of the graphite upper mold 1;

[0039] 3) The assembled sintered parts are placed in a chain atmosphere furnace at a certain temperature for primary sintering. After the sintering is completed, the mold is taken out and disassembled to obtain the low-frequency micro rectangular connector to be processed; the primary sintering process is 1000° C. to 1030° C., the belt speed is 35 to 45 mm / min, the nitrogen atmosphere, and the sintering time is 4.5 h.

[0040] 4) The low-frequency micro-rectangular connector to be processed is immersed in a concentrated hydrofluoric acid solution for pickling, and then dried after a certain period of time; the pickling process is to put the connector into the pickling tooling, soak it in a concentrated HF solution for 15 minutes, until the glass surface height is slightly higher than the shell, that is, 0.2-0.5mm, observed under a 25x microscope, and then put it into a 50℃ saturated NaCO3 solution for neutralization and ultrasonic treatment for 10 minutes, and then change to 45℃ hot water ultrasonic treatment for 10 minutes, and finally soak it in a 60℃ hot alcohol solution for 30 seconds, and put it in a 200℃ oven for drying for 30 minutes. The purpose of the first pickling is to remove impurities such as graphite and iron filings in step 2); remove the part where the whole glass overflows the shell, splashes, and the glass climbs along the metal inner conductor in step 3); controlling the height of the glass higher than the metal shell is to prepare for the uniformity of the glass height of the high-frequency part in step 7), so as to prevent the problem of low product yield caused by too little glass.

[0041] 6) The pickled low-frequency micro rectangular connector is subjected to secondary pre-oxidation treatment at a certain temperature; the pre-oxidation process is at 650-680°C, 2L / min high-temperature humidified nitrogen atmosphere, and a belt speed of 50mm / min. The oxidation time is 1.5 hours.

[0042] 7) The pre-oxidized connector is reassembled with the graphite mold; the assembly sequence is graphite lower mold 1, pickled connector, high-frequency glass insulator 13, high-frequency metal inner conductor 12, graphite upper mold 1, and graphite upper mold 2; the outer edge of the metal shell 9 is matched with the first lower groove 2 of the graphite lower mold 1; the high-frequency glass insulator 13 is arranged in the circular single hole of the metal shell 9, and the upper surface is matched with the second lower groove 3 of the graphite lower mold 1; the high-frequency metal inner conductor 13 passes through the single hole position of the graphite lower mold and the single hole position of the high-frequency glass insulator, and finally the upper single hole position 8 of the graphite upper mold 2 passes through the high-frequency metal inner conductor 13, and after the graphite upper mold 2 boss 7 is matched with the circular inner cavity edge of the metal shell 9, the graphite upper mold 1 is placed, and finally a whole piece of stainless steel sheet of about 15g is covered on the graphite upper mold;

[0043] 8) The assembled connector is placed in a chain atmosphere furnace at a certain temperature for secondary sintering. After the sintering is completed, the mold is taken out and disassembled to obtain the composite micro-rectangular connector to be processed; the secondary sintering process is 1000°C to 1030°C, the belt speed is 35 to 45 mm / min, the nitrogen atmosphere, and the sintering time is 4.5h.

[0044] 9) Mechanically grind the side end face and the upper end face of the metal shell of the composite micro rectangular connector to be processed, and put it into a deburring machine for deburring treatment until the bonding end face of each metal inner conductor is smooth and flat without burrs, iron filings, and scratches;

[0045] 10) The deburred composite micro-rectangular connector is immersed in a concentrated hydrofluoric acid solution for secondary pickling, and the treatment is carried out for a certain period of time until the height of the glass surface of the product does not exceed the surface of the metal shell when observed from the side, and then dried; the secondary pickling process is to place the connector in the pickling tooling, soak it in a concentrated hydrofluoric acid solution for 7 minutes until the glass surface of the product is lower than the surface of the metal shell, and then put it into a 50℃ saturated NaCO3 solution for neutralization and ultrasonic treatment for 10 minutes, and then change to 45℃ hot water ultrasonic treatment for 10 minutes, and finally soak it in a 60℃ hot alcohol solution for 30 seconds, and put it in a 200℃ oven for drying for 30 minutes. The purpose of secondary pickling is to remove impurities such as iron filings caused by wire grinding in step 9); at the same time, remove glass splashing, glass graphite adhesion, impurities on the glass surface, etc. caused by the glass being higher than the metal shell in step 8), and ensure that the height of each glass insulator is lower than the metal shell interface and meets the requirement that the difference between the lowest surface of the glass surface after the arc is reversed and the surface of the shell is less than 0 to 0.15.

[0046] 11) The pickled composite micro rectangular connector is assembled again with the graphite lower mold, graphite upper mold one and graphite mold two, and placed in a chain atmosphere furnace at a certain temperature for three sinterings. After the sintering is completed, the mold is taken out and disassembled to obtain a semi-finished composite micro rectangular connector; the three sintering processes are 1000°C to 1030°C, the belt speed is 35 to 45 mm / min, the nitrogen atmosphere, and the sintering time is 4.5h.

[0047] 12) The semi-finished micro-rectangular connector is immersed in a mixed acid solution for three pickling treatments to remove the graphite and impurities remaining in the sintering process, and finally the product is dried to obtain a finished composite micro-rectangular connector. The three-pickling process is to place the connector in a pickling tool, immerse it in a mixed acid solution, wherein the volume ratio of water, hydrofluoric acid and hydrochloric acid is H2O:HF:HCl=17-19:1:1, and then put it into a 50°C saturated NaCO3 solution for neutralization and ultrasonic treatment for 10 minutes, then replace it with 45°C hot water ultrasonic treatment for 10 minutes, and finally soak it in a 60°C hot alcohol solution for 30 seconds, and put it in a 200°C oven for drying for 30 minutes.

[0048] In this embodiment, the upper mold is a split mold, and the expansion coefficients of different components are calculated separately, which can effectively avoid product eccentricity and core column bending caused by expansion; the lower mold does not distinguish between new firing and re-firing, and the lower mold is designed with a first groove and a second groove. When newly fired, the glass is guaranteed to increase by 0.3mm in height downward, which is conducive to ensuring the consistency of flatness with high-frequency glass and reducing the risk of glass holes and glass subsidence; when re-firing, the gap between the small step and the glass is 0.3mm, ensuring that the exposed metal inner conductor meets the required size, avoiding the problem of poor insulation on the surface of the product glass due to graphite adhesion, and reducing costs at the same time.

[0049] In this embodiment, the high-frequency sealing hole of the metal shell has a diameter of 1 to 1.2 mm and a height of 3.0 to 4.5 mm; the diameter of the high-frequency metal inner conductor is 0.3 to 0.45 mm and the length is 5.5 to 6.0 mm; the high-frequency glass insulator is BH-24G / K, with an outer diameter of 1.05 to 1.15 mm, an inner diameter of 0.45 to 0.55 mm and a height of 1.7 to 2.0 mm; the low-frequency of the metal shell is a 25 to 37-core J63 or J30 micro rectangular connector, and the low-frequency glass insulator is BH-G / K with a height of 3.5 to 5.0 mm.

[0050] The connector obtained in this embodiment was subjected to performance testing, and the results are as follows:

[0051]

[0052] The above implementation modes are only used to illustrate the present invention, but not to limit the present invention. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also belong to the scope of the present invention. The patent protection scope of the present invention should be defined by the claims.

Claims

1. A method for preparing a high-low frequency composite micro rectangular connector, characterized in that: The micro rectangular connector mainly includes a metal shell, a plurality of metal inner conductors and a glass insulator. The metal shell includes a high-frequency connector part and a low-frequency connector part. In the high-frequency connector part, the high-frequency glass insulator is arranged in the circular hole of the metal shell, and the high-frequency metal inner conductor is inserted into a single circular hole of the high-frequency glass insulator. In the low-frequency connector part, the low-frequency glass insulator is arranged in the low-frequency hole, and the low-frequency metal inner conductor is inserted into multiple circular holes of the low-frequency glass insulator. The upper end faces and lower end faces of the high-frequency and low-frequency metal inner conductors are both flush, and the glass surfaces are both flush after sintering. The method for preparing the micro rectangular connector comprises the following steps: 1) Mold design: the high-frequency connector part and the low-frequency connector part are designed as a split assembly mode. The graphite mold includes a graphite lower mold, a graphite upper mold 1 and a graphite upper mold 2. The graphite lower mold and the graphite upper mold 1 are respectively provided with an upper multi-porous position and a lower multi-porous position, and the graphite upper mold 2 is provided with an upper single-hole position; 2) Degreasing and cleaning the metal shell, each metal inner conductor, and the graphite mold, and after sintering in a furnace, pre-oxidizing the metal shell and each metal inner conductor; 3) Assemble the pre-oxidized metal shell, high-frequency and low-frequency metal inner conductors, and high-frequency and low-frequency glass insulators in a graphite mold; the graphite mold includes a graphite lower mold and a graphite upper mold, and the metal shell is arranged between the graphite upper mold and the graphite lower mold; the low-frequency glass insulator is arranged in the low-frequency hole of the metal shell, and each low-frequency metal inner conductor passes through the lower porous position of the graphite lower mold, the porous position of the low-frequency glass insulator, and the upper porous position of the graphite upper mold, and then covers the upper graphite upper mold with a certain weight of stainless steel sheet; 4) placing the assembled sintered parts into a chain atmosphere furnace at a certain temperature for a sintering process. After the sintering process is completed, taking out and disassembling the mold to obtain the low-frequency micro rectangular connector to be processed; 5) Soak the low-frequency micro-rectangular connector to be processed in a concentrated hydrofluoric acid solution for pickling for a certain period of time until the glass surface of the product shows obvious fish scale corrosion marks when observed under a microscope at 25 times, and the height of the glass surface is slightly higher than the metal shell, and then dry it; 6) The pickled low-frequency micro-rectangular connector is subjected to secondary pre-oxidation treatment at a certain temperature and secondary assembly with a graphite mold; the graphite mold comprises a graphite lower mold, a graphite upper mold 1 and a graphite upper mold 2, and the pickled low-frequency micro-rectangular connector is arranged between the graphite upper mold and the graphite lower mold; the high-frequency glass insulator is arranged in a single circular hole of the metal shell, and the high-frequency metal inner conductor passes through the single hole position of the graphite lower mold, the single hole position of the high-frequency glass insulator and the single hole position of the graphite upper mold 2, and the graphite upper mold 1 is placed at the same time, and finally a certain weight of stainless steel sheet is covered on the graphite upper mold 1 and the graphite upper mold 2; it is placed in a chain atmosphere furnace at a certain temperature for secondary sintering, and after the sintering is completed, the mold is taken out and disassembled to obtain a micro-rectangular connector to be processed; 7) Mechanically grind the side end face and the upper end face of the metal shell of the composite micro rectangular connector to be processed, and put it into a deburring machine for deburring treatment until the bonding end face of each metal inner conductor is smooth and flat without burrs, iron filings, and scratches; 8) The deburred composite micro rectangular connector is immersed in a concentrated hydrofluoric acid solution for secondary pickling for a certain period of time until the height of the glass surface of the product does not exceed the surface of the metal shell when observed from the side, and then dried; 9) Assemble the pickled composite micro rectangular connector again with the re-sintered graphite lower mold, the graphite upper mold 1 and the graphite upper mold 2, put it into a chain atmosphere furnace at a certain temperature for three sinterings, and after the sintering is completed, take out and disassemble the mold to obtain a semi-finished composite micro rectangular connector; 10) The semi-finished micro-rectangular connector is immersed in a mixed acid solution for three acid washing treatments to remove graphite and impurities remaining in the sintering process, and finally the product is dried to obtain a finished composite micro-rectangular connector.

2. The method for preparing a high-low frequency composite micro rectangular connector according to claim 1, characterized in that: In step 2), the furnace sintering process is sintering in a chain sintering furnace at 920°C to 940°C; the degreasing process is ultrasonic treatment in a saturated detergent solution for 10 to 20 minutes; the pre-oxidation treatment process is at 650 to 680°C, 2L / min high-temperature humidified nitrogen atmosphere, and a belt speed of 50mm / min.

3. The method for preparing a high-low frequency composite micro rectangular connector according to claim 1, characterized in that: In step 3), the assembly order is graphite lower mold, metal shell, low-frequency glass insulator, low-frequency metal inner conductor, and graphite upper mold one; the low-frequency glass insulator is integrally sintered glass, and the overall glass hole gap is 0.635±0.05; the average weight of the stainless steel sheet covering each connector is 0.5~1g.

4. The method for preparing a high-low frequency composite micro rectangular connector according to claim 1, characterized in that: In step 3), a first lower groove is provided on the graphite lower mold, a second lower groove is provided in the first lower groove, and a certain step surface is formed between the first lower groove and the second lower groove; a plurality of the lower porous positions are provided in the second lower groove; during assembly, the first lower groove is embedded with the outer edge of the metal shell; the second lower groove is embedded with the outer edge of the low-frequency glass insulator.

5. The method for preparing a high-low frequency composite micro rectangular connector according to claim 1, characterized in that: In step 3), the graphite lower mold matches the graphite upper mold 1 and the graphite upper mold 2; the graphite upper mold 1 and the graphite upper mold 2 are respectively provided with a graphite upper mold 1 boss and a graphite upper mold 2 boss, and the graphite upper mold 1 boss is provided with a plurality of upper porous positions; during assembly, the boss is embedded in the inner cavity of the metal shell, and the upper porous position is inserted in cooperation with the low-frequency metal inner conductor.

6. The method for preparing a high-low frequency composite micro rectangular connector according to claim 1, characterized in that: The upper multi-hole position of the graphite upper die 1 is a blind hole, the upper single hole position of the graphite upper die 2 is a blind hole, and the lower multi-hole position of the graphite lower die is a blind hole.

7. The method for preparing a high-low frequency composite micro rectangular connector according to claim 1, characterized in that: In the composite micro-rectangular connector, the metal shell and each metal inner conductor are made of Kovar alloy; the high-frequency sealing hole of the metal shell has a diameter of 1 to 1.2 mm and a height of 3.0 to 4.5 mm; the diameter of the high-frequency metal inner conductor is 0.3 to 0.45 mm and a length of 5.5 to 6.0 mm; the high-frequency glass insulator is BH-24G / K, with an outer diameter of 1.05 to 1.15 mm, an inner diameter of 0.45 to 0.55 mm and a height of 1.7 to 2.0 mm; the low-frequency of the metal shell is a 25-37-core J63 or J30 micro-rectangular connector, and the low-frequency glass insulator is BH-G / K with a height of 3.5 to 5.0 mm.

8. The method for preparing a high-low frequency composite micro rectangular connector according to claim 1, characterized in that: In step 4), the sintering process is 1000° C. to 1030° C., a belt speed of 35 to 45 mm / min, and a nitrogen atmosphere.

9. The method for preparing a high-low frequency composite micro rectangular connector according to claim 1, characterized in that: In step 5), a pickling process is performed by placing the connector in a pickling tool and immersing it in a concentrated hydrofluoric acid solution until obvious fish scale corrosion marks appear on the glass surface of the product when observed under a microscope at 25 times. After the height of the glass surface is slightly higher than the shell, it is placed in a saturated NaCO3 solution for neutralization and ultrasonic treatment for 10 to 15 minutes, then replaced with 45°C hot water for ultrasonic treatment for 10 to 15 minutes, and finally immersed in a 60°C hot alcohol solution for 20 to 40 seconds and dried.

10. The method for preparing a high-low frequency composite micro rectangular connector according to claim 1, characterized in that: In step 7), the secondary pickling process is to place the connector in a pickling tool, immerse it in a concentrated hydrofluoric acid solution for a certain period of time until the glass surface of the product is lower than the surface of the metal shell, put it into a saturated NaCO3 solution for neutralization and ultrasonic treatment for 10 to 15 minutes, then change to 45°C hot water ultrasonic treatment for 10 to 15 minutes, and finally immerse it in a 60°C hot alcohol solution for 20 to 40 seconds and then dry it.

11. The method for preparing a high-low frequency composite micro rectangular connector according to claim 1, characterized in that: In step 10), the three pickling processes are to place the connector in a pickling tool, immerse it in a mixed acid solution, wherein the volume ratio of water, hydrofluoric acid and hydrochloric acid is H2O:HF:HCl=17-19:1:1, and then put it into a saturated NaCO3 solution for neutralization and ultrasonication for 10-15 minutes, then replace it with 45°C hot water and ultrasonicate for 10-15 minutes, and finally immerse it in a 60°C hot alcohol solution for 20-40 seconds and then dry it.

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