Manufacturing Method of Encapsulated Metal Shell Relay

Abstract

The present invention relates to a manufacturing method of an encapsulated metal shell relay, which includes manufacturing a metal oxide layer of a ceramic insulator; then, welding the ceramic insulator to the shell through the metal oxide layer. In the step of manufacturing the metal oxide layer of the ceramic insulator, the following steps are performed; Step I, select a graphite plate; Step II, machine a groove in the center of the graphite plate; Step III, select a ceramic insulator and place it in the groove, with the holes of the ceramic insulator placed parallel to the groove of the graphite plate; Step IV, place a solder with a diameter of Ag72Cu28 above the ceramic insulator; Step V, use a 4J42 nickel-plated cover plate and place it above the Ag72Cu28 solder; Step VI, first, bend and shape a molybdenum sheet; then, fix the 4J42 nickel-plated cover plate to the graphite plate with the bent molybdenum sheet; The design of the present invention is reasonable, the structure is compact, and it is convenient to use.

Description

Technical Field

[0001] The present invention relates to a manufacturing method of an encapsulated metal shell relay. Background Art

[0002] At present, the ceramic insulator for relay encapsulation is the most important component in the ceramic-metal encapsulation shell and is widely used in the optoelectronic communication field. The side of the ceramic insulator for relay encapsulation needs to have a metallization layer, that is, a metal film that is firmly bonded to the ceramic and not easily melted is added to its side, so that the ceramic insulator and the metal part can be welded together with a high-temperature solder here. The quality of the ceramic insulator metallization depends on the quality of the ceramic itself and the metallization process. The main factors affecting the metallization quality in the metallization process are the thickness and uniformity of the metallization layer, the sintering method, etc. If the ceramic metallization layer is not firm, it will cause poor airtightness of the shell during the sintering of the metal-ceramic shell, and the insulation and withstand voltage cannot meet the use conditions. In the prior art, there is no specific method for testing the firmness of the metallization layer of the ceramic insulator. The firmness of the metallization layer of the ceramic insulator cannot be batch-tested before use, and the produced products have a risk of failure.

[0003] Ag72Cu28 solder is the most widely used solder on the relay encapsulation shell at present. It has a low melting point, good fluidity, and the formed weld has good thermal and electrical conductivity properties. In the brazing process of the relay encapsulation shell, the fluidity of the silver-copper solder has an important impact on the appearance, airtightness, reliability, etc. of the device.

[0004] Under the same brazing system, if the fluidity of the silver-copper solder is properly controlled and the solder spreads evenly, a flat and tight bonding interface can be achieved, ensuring the airtightness during the period and achieving high reliability. If the silver-copper solder flows excessively and the spreading area of the solder is too large, it will cause virtual soldering at the bonding interface, affecting the airtightness and reliability, and also affecting the bonding force and appearance of the coating after the shell is plated. If the solder flows to the end of the leg, it will affect the bonding performance of the leg, etc. The present invention can solve the problem that the excessive fluidity of the silver-copper solder during brazing affects the performance, quality, reliability and appearance of the relay encapsulation shell.

[0005] Most of the high-power three-phase solid-state relays produced by domestic and foreign manufacturers are plastic encapsulated at present. Since the plastic is formed by vulcanization, a draft angle will be generated. Moreover, in order to improve the strength, its wall thickness is large, so the volume is large, with dimensions of about 105mm×75mm×35mm, and the use environment is limited. If the wall thickness is reduced, the housing of the electrical device will be greatly reduced, and its heat dissipation performance is poor, static electricity is easily accumulated, and the shell is easily oxidized, thus seriously damaging the electrical components.

[0006] At present, metal enclosures for electronic packaging are widely used in various military and civilian fields such as aviation, aerospace, ships, radar, missiles, weapons, instrumentation, and communications. Limited by surface treatment materials and process technologies, after the surface treatment process of most metal enclosures is completed, the pin length of the enclosures needs to meet the technical requirements and the surface should be free of damage. Coupled with the diverse shapes and structures of the enclosures, in the mass production of some models of metal enclosures for electronic packaging, the previous cutting devices could not meet the production progress and process requirements, resulting in low production efficiency.

[0007] Existing ordinary cutting knives are slow in cutting, have poor safety, low efficiency, and are prone to producing unqualified products, unable to ensure the stable reliability of product quality. Previous cutting devices were all manual cutting with ordinary cutting knives. Manual operation is slow and prone to fatigue, and the safety of the cutting knives is also poor. Once there is jitter during the product cutting process, it may cause damage to the product surface and is prone to unqualified products, resulting in low efficiency of the production process and being unable to meet the production progress and process requirements of metal enclosures. Summary of the Invention

[0008] Generally speaking, the technical problem to be solved by the present invention is to provide a manufacturing method for a relay with a packaged metal enclosure. The present invention gives a specific and operable inspection method for the firmness inspection of the metalized layer of ceramic insulators used in current metal-ceramic enclosures.

[0009] To solve the above problems, the technical solutions adopted by the present invention are as follows:

[0010] A manufacturing method for a relay with a packaged metal enclosure. First, manufacture the metal oxide layer of the ceramic insulator; then, weld the ceramic insulator to the enclosure through the metal oxide layer.

[0011] As a further improvement of the above technical solution:

[0012] In the step of manufacturing the metal oxide layer of the ceramic insulator, the following steps are carried out;

[0013] Step I: Select a graphite plate;

[0014] Step II: Machine a groove in the center of the graphite plate;

[0015] Step III: Select a ceramic insulator and place it in the groove. The holes of the ceramic insulator are placed parallel to the groove of the graphite plate;

[0016] Step IV: Place a solder with a diameter of Ag72Cu28 above the ceramic insulator;

[0017] Step V: Place a 4J42 nickel-plated cover plate above the Ag72Cu28 solder;

[0018] Step VI. First, bend and shape the molybdenum sheet; then, fix the 4J42 nickel-plated cover plate with the bent molybdenum sheet on the graphite plate.

[0019] Step VII. Place the workpiece from Step VI into a sintering furnace under gas protection for sintering.

[0020] Step VIII. Take out the sintered ceramic insulator and pull the ceramic insulator with a preset force. If the ceramic insulator is separated from the 4J42 nickel-plated cover plate, the firmness is poor; otherwise, the firmness is good.

[0021] During the process of welding the ceramic insulator to the housing through the metal oxide layer, the specific steps are as follows:

[0022] Step A. Clean the surfaces of the ceramic insulator and the housing to remove impurities.

[0023] Step B. Electroplate nickel on the housing.

[0024] Step C. Place the housing in a furnace under nitrogen protection and perform pretreatment in groups.

[0025] Component Status Front Scattering Area (cm2) Lead Scattering Length (mm) Original Treatment Plan 1.9-2.1 5-6 Curve 1 0.3-0.6 2mm Curve 2 0.2-0.4 1-2 Curve 3 0.1-0.2 <1mm Curve 4 0.4-0.6 1-2.5 Curve 5 0.2-0.5 1.2 Curve 6 0.1-0.3 1-1.5 Curve 7 0.5-0.8 2-3 Curve 8 0.3-0.5 1-3 Curve 9 0.2-0.3 1-2

[0026] Step D. After assembling the housing, perform brazing.

[0027] Step E. Visually inspect and measure under a microscope to count the solder spreadability.

[0028] Step F. According to the standard, perform a sealing test, and the test results of each group are less than 1×10-9 Pa·m3 / s.

[0029] Step G. According to the test sealing results that are all less than 1×10-9 Pa·m3 / s, it is proved that the brazing effect of each group of experiments is good.

[0030] After Step G, perform Step H. Statistically conclude, and according to the experimental results statistics, perform parts pretreatment according to Curve 3.

[0031] Before or after welding the ceramic insulator to the housing through the metal oxide layer, encapsulate the metal housing relay assembly in the installed housing; including the following steps,

[0032] Step 1. First, install the printed circuit board with installed electronic components on the housing; then, install injection pads at the U-shaped inlets at the four corners of the housing.

[0033] Step 2: First, install the bottom welding bracket on the process through hole of the cover plate; then, place the upper gap-adjusting diaphragm on the bottom welding bracket; secondly, place the water-isolating membrane on the upper gap-adjusting diaphragm; thirdly, install the gap-adjusting diaphragm on the water-isolating membrane so that the upper surface of the gap-adjusting diaphragm is higher than the upper port of the process through hole; then, install the upper pressure grid on the gap-adjusting diaphragm.

[0034] The present invention has a reasonable design, low cost, durability, safety, reliability, simple operation, time and labor saving, cost saving, compact structure and convenient use. While ensuring the brazing effect, the present invention effectively controls the diffusivity of the silver-copper solder, thereby improving the brazing performance and product reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is an assembly diagram of the method for testing the firmness of the metallized layer of ceramic insulators.

[0036] Figure 2 is the sintering curve in this method.

[0037] Figure 3 This is a reference diagram for comparing the actual welding effects of the present invention.

[0038] Figure 4 It is a schematic diagram of curve 1-3 of the present invention.

[0039] Figure 5 It is a schematic diagram of curves 4-6 of the present invention.

[0040] Figure 6 It is a schematic diagram of curves 7-9 of the present invention.

[0041] Figure 7 It is a structural schematic diagram of the present invention from a first viewing angle.

[0042] Figure 8 It is a structural schematic diagram of the second viewing angle of the present invention.

[0043] Figure 9 It is a schematic diagram of the improved structure of the present invention.

[0044] Figure 10 Schematic diagram of the circuit of the present invention.

[0045] Among them: 31. Printed circuit board; 32. Power components; 33. Cover; 34. Housing; 35. Process through-hole; 36. Bottom solder bracket; 37. Upper gap adjustment diaphragm; 38. Water-proof membrane; 39. Upper pressure grid; 40. U-shaped inlet; 41. Process side flaring; 42. Injection molded gasket; 61. Graphite plate; 62. Groove; 63. Ceramic insulator; 64. Ag78Cu22 solder; 65. 4J42 nickel-plated cover; 66. Molybdenum sheet. DETAILED DESCRIPTION

[0046] As Figures 1 - 10 shown, the manufacturing system of the encapsulated metal shell relay in this embodiment includes a metal shell relay with an electrical module installed in its inner cavity in the shell 34. A graphite plate 61 is provided on the shell 34, grooves 62 are machined on the graphite plate 61, ceramic insulators 63 are placed in parallel in the grooves 62, a 4J42 nickel-plated cover plate 65 is provided on the graphite plate 61 above the ceramic insulators 63, Ag72Cu28 solder 64 with a diameter of 2.7 mm is placed above the ceramic insulators 63, a 4J42 nickel-plated cover plate 65 is placed above the Ag72Cu28 solder 64 above the graphite plate 61, and a bent molybdenum sheet 66 is provided between the 4J42 nickel-plated cover plate 65 and the graphite plate 61.

[0047] The molybdenum sheet 66 has a trapezoidal structure with an open upper end. The lower bottom plate of the molybdenum sheet 66 contacts the lower surface of the graphite plate 61. On both slant sides of the molybdenum sheet 66, lower elbows are provided at the corners of the two slant sides for pressure contact with the two sides of the upper surface of the 4J42 nickel-plated cover plate 65.

[0048] An oxide film is provided on the shell 34, the cover plate 33 or the pins.

[0049] The metal shell relay includes a cover plate 33 sealed and fastened on the shell 34, a process through hole 35 is provided on the cover plate 33, a bottom welding bracket 36 with a mesh hole is hermetically welded to the inner side wall of the cover plate 33 around and is located directly below the process through hole 35, an upper gap-adjusting diaphragm 37 is provided on the bottom welding bracket 36 and is located below the process through hole 35, a water-proof diaphragm 38 is located in the process through hole 35 and above the upper gap-adjusting diaphragm 37, an upper pressure grid 39 is installed on the cover plate 33 through bolts, and a gap-adjusting diaphragm with the same structure as the upper gap-adjusting diaphragm 37 is provided between the upper pressure grid 39 and the upper gap-adjusting diaphragm 37; the sum of the thicknesses of the upper gap-adjusting diaphragm 37, the water-proof diaphragm 38 and the gap-adjusting diaphragm is greater than the depth of the process through hole 35; the pore diameter of the water-proof diaphragm 38 is smaller than the diameter of water molecules;

[0050] The thicknesses of the upper gap-adjusting diaphragm 37, the water-proof diaphragm 38 and the gap-adjusting diaphragm are selected according to the depth of the process through hole 35; a filter is externally connected to the upper pressure grid 39, and a filter is externally connected to the filter.

[0051] The shell 34 and the cover plate 33 are electroplated or sprayed with corresponding anti-corrosion layers according to the working conditions;

[0052] U-shaped inlets 40 are provided at the four corners of the bottom plate of the shell 34, and process two-side flared openings 41 wider than the U-shaped inlets 40 are provided in the U-shaped inlets 40; the U-shaped inlets 40 and the process two-side flared openings 41 form a mushroom-shaped space, and injection molding gaskets 42 for connecting bolts are thermoplastically formed on the inner side wall and the upper and lower surfaces of the process two-side flared openings 41;

[0053] The electrical appliance module includes a printed circuit board 31 which is disposed on the bottom plate of the inner cavity of the housing 34 and is electrically connected to each other; a power component 32 is soldered or inserted on one side of the printed circuit board 31, and the other side of the printed circuit board 31 is a copper-clad area;

[0054] The power component 32 includes an isolation input module, a zero-crossing detection module and an output circuit module which are electrically connected in sequence;

[0055] The input circuit of the isolation input module uses a constant current source control method, and the input voltage range is 6VDC - 32VDC;

[0056] The zero-crossing detection module uses an optocoupler;

[0057] The output circuit module as the power output includes multiple reverse-parallel unilateral thyristors, and an RC absorption circuit is electrically connected to both ends of the unilateral thyristor.

[0058] For the manufacturing method of the encapsulated metal shell relay in this embodiment, first, the metal oxide layer of the ceramic insulator 63 is manufactured; then, the ceramic insulator 63 is welded to the housing 34 through the metal oxide layer.

[0059] In the step of manufacturing the metal oxide layer of the ceramic insulator 63, the following steps are executed;

[0060] Step I: Select a graphite plate 61;

[0061] Step II: Process a groove 62 in the center of the graphite plate 61;

[0062] Step III: Select a ceramic insulator 63 and place it in the groove 62, and the holes of the ceramic insulator are placed parallel to the groove of the graphite plate 61;

[0063] Step IV: Place a solder 64 with a diameter of Ag72Cu28 above the ceramic insulator 63;

[0064] Step V: Place a 4J42 nickel-plated cover plate 65 above the Ag72Cu28 solder 64;

[0065] Step VI: First, bend and shape the molybdenum sheet 66; then, the bent molybdenum sheet 66 fixes the 4J42 nickel-plated cover plate 65 on the graphite plate 61;

[0066] Step VII: Place the workpiece in step VI in a gas-protected sintering furnace for sintering;

[0067] Step VIII: Take out the sintered ceramic insulator 63, pull the ceramic insulator 63 with a preset force. If the ceramic insulator 63 is separated from the 4J42 nickel-plated cover plate 65, the firmness is poor, otherwise, the firmness is good.

[0068] During the process of welding the ceramic insulator 63 to the housing 34 through a metal oxide layer, the specific steps are as follows:

[0069] Step A: Clean the surfaces of the ceramic insulator 63 and the housing 34 to remove impurities;

[0070] Step B: Electroplate the housing 34 with nickel;

[0071] Step C: Place the housing 34 in a furnace protected by nitrogen and perform pre-treatment in groups;

[0072] Step D: After assembling the housing 34, perform brazing;

[0073] Step E: Visually inspect and measure under a microscope to count the solder spreadability;

[0074] Step F: According to the standard, perform a seal test, and the test results of each group are all less than 1×10-9 Pa·m3 / s;

[0075] Step G: According to the seal test results being all less than 1×10-9 Pa·m3 / s, it is proved that the brazing effect of each group of experiments is good.

[0076] In Step VII, place the workpiece of Step VI in a sintering furnace protected by gas and sinter according to the sintering curve in the curve table; Figure 2 The sintering curve of the curve table is carried out for sintering;

[0077] In Step C, place the housing (34) in a furnace protected by nitrogen and perform pre-treatment in groups as follows in the table;

[0078] Component Status Front Scattering Area (cm2) Lead Scattering Length (mm) Original Treatment Plan 1.9-2.1 5-6 Curve 1 0.3-0.6 2mm Curve 2 0.2-0.4 1-2 Curve 3 0.1-0.2 <1mm Curve 4 0.4-0.6 1-2.5 Curve 5 0.2-0.5 1.2 Curve 6 0.1-0.3 1-1.5 Curve 7 0.5-0.8 2-3 Curve 8 0.3-0.5 1-3 Curve 9 0.2-0.3 1-2

[0079] Among them, in Step C, set the following curves on each table of the furnace for pre-treatment;

[0080] Curves 1-3, such as Figure 4 The curve is pre-treated; in Curves 4-6, such as Figure 5 The curve is pre-treated; in Curves 7-9, such as Figure 6 The curve is pre-treated; in Step F, according to Method 1014 of GJB 548B-2005, test condition A4 is used for the seal test, and the test results are all less than 1×10-9 Pa·m3 / s; T

[0081] In Step G, according to Method 1010 condition F of GJB 548B-2005, perform a temperature cycle of -65°C - 175°C, 100 times. After the temperature cycle, measure the seal result, which is all less than 1×10-9 Pa·m3 / s. This test proves that the brazing effect of these 9 groups of experiments is good;

[0082] After step G, perform step H, statistical conclusion. According to the experimental results statistics, preprocess the components according to curve 3.

[0083] Before or after the ceramic insulator (63) is welded to the housing (34) through a metal oxide layer, encapsulate the metal housing relay assembly in the mounting housing (34); including the following steps,

[0084] Step 1, first, install the printed circuit board with installed electronic components (31) on the housing (34); then, install the injection molding gasket (42) at the U-shaped inlet (40) at the four corners of the housing (34);

[0085] Step 2, first, install the bottom welding bracket (36) at the process through hole (35) of the cover plate (33); then, place the upper gap adjusting diaphragm (37) on the bottom welding bracket (36); secondly, place the water isolation film (38) on the upper gap adjusting diaphragm (37); thirdly, fit the gap adjusting diaphragm on the water isolation film (38) so that the upper surface of the gap adjusting diaphragm is higher than the upper port of the process through hole (35); immediately afterwards, install the upper pressure grid frame (39) on the gap adjusting diaphragm.

[0086] As a preference, as Figures 1 - 2 , for the manufacturing system of the encapsulated metal housing relay, the inspection principle: Sinter the Ag78Cu22 solder (64) and the 4J42 nickel-plated cover plate (65) together according to a certain sintering curve. After sintering, apply a certain force to the insulator. If the ceramic insulator (63) and the 4J42 nickel-plated cover plate (65) fall off, it indicates that the firmness of the metallized layer of the ceramic insulator (63) is poor, otherwise it indicates that the firmness of the metallized layer of the insulator is good.

[0087] A graphite plate (61) is provided on the housing (34), a groove (62) is machined on the graphite plate (61), a ceramic insulator (63) is placed in parallel in the groove (62), a 4J42 nickel-plated cover plate (65) is provided above the ceramic insulator (63) on the graphite plate (61), an Ag72Cu28 solder (64) with a diameter of 2.7 mm is placed above the ceramic insulator (63), a 4J42 nickel-plated cover plate (65) is placed above the Ag72Cu28 solder (64) above the graphite plate (61), a bent molybdenum sheet (66) is provided between the 4J42 nickel-plated cover plate (65) and the graphite plate (61), the molybdenum sheet (66) has a trapezoidal structure with an open upper end, the lower bottom plate of the molybdenum sheet (66) is in contact with the lower surface of the graphite plate (61), and the two slant sides of the molybdenum sheet (66) are provided with lower elbows at the upper corners of the two slant sides for pressure contact with the two sides of the upper surface of the 4J42 nickel-plated cover plate (65);

[0088] As a specific case, Example 1, Step 1: Select a graphite plate (61) with a length, width and height of 60 mm × 22 mm × 6 mm respectively, as shown in the appendixFigure 1 as shown in Fig. 1;

[0089] Step 2: Use sandpaper to grind a groove (62) with a diameter of 1.5 mm in the center of the graphite plate (61), as shown in Fig. 2; Figure 1 as shown in Fig. 2;

[0090] Step 3: Select a ceramic insulator (63) with a diameter of 2.7 mm and place it in the groove (62). The hole of the ceramic insulator is placed parallel to the groove of the graphite plate (61), as shown in Fig. 3; Figure 1 as shown in Fig. 3;

[0091] Step 4: Place a Ag72Cu28 solder (64) with a diameter of 2.7 mm above the ceramic insulator (63), as shown in Fig. 4; Figure 1 as shown in Fig. 4;

[0092] Step 5: Place a 4J42 nickel-plated cover plate (65) with a length of 60 mm, a width of 2 mm, and a thickness of 0.4 mm above the Ag72Cu28 solder (64), as shown in Fig. 5; Figure 1 as shown in Fig. 5;

[0093] Step 6: Use a bent molybdenum sheet (66) to fix the 4J42 nickel-plated cover plate (65) on the graphite plate (61), as shown in Fig. 6; Figure 1 as shown in Fig. 6;

[0094] Step 7: Place the assembled workpiece in a sintering furnace protected by a nitrogen atmosphere for sintering according to the sintering curve in Fig.; Figure 2 of Fig.;

[0095] Step 8: Take out the sintered ceramic insulator (63) and pull the insulator with a force of 10 N. If the insulator is separated from the 4J42 nickel-plated cover plate (65), the firmness is poor; otherwise, the firmness is good.

[0096] The present invention solves the problem of testing the firmness of the metallized layer of the ceramic insulator (63), and avoids the problems of poor airtightness of the metal-ceramic shell and inability to meet the use requirements of insulation withstand voltage caused by the unfirm metallized layer of the ceramic insulators (63) produced in the same batch.

[0097] Welding principle for the manufacturing method of the encapsulated metal shell relay: After pretreatment, a dense iron-based oxide film is formed on the surface of the lead wire and the shell (34). The oxide film, as a binder, dissolves in the glass and the metal or alloy. During the sealing, a gradual structural transformation occurs between the oxide tightly attached to the surface of the metal or alloy and the glass, forming a transition layer structure, which reduces the flowability range of the solder during encapsulation and results in a better encapsulation effect.

[0098] Example 2, Step 1: Clean the surface of the welded parts to remove impurities such as oil stains and oxides.

[0099] Step 2: Coat the shell of the relay encapsulation with a layer of electroplated nickel, with the thickness controlled within 0.5 - 1.5 microns.

[0100] Step 3: Place components such as the shell and leads in a furnace protected by a nitrogen atmosphere, and set the furnace with the following curve for pre - treatment in 9 groups.

[0101] Step 4: Assemble the pre - treated components for soldering.

[0102] Step 5: Visually inspect and measure under a microscope, and count the solder spreadability. The statistical results are as follows.

[0103] Component Status Front Scattering Area (cm2) Lead Scattering Length (mm) Original Treatment Plan 1.9-2.1 5-6 Curve 1 0.3-0.6 2mm Curve 2 0.2-0.4 1-2 Curve 3 0.1-0.2 <1mm Curve 4 0.4-0.6 1-2.5 Curve 5 0.2-0.5 1.2 Curve 6 0.1-0.3 1-1.5 Curve 7 0.5-0.8 2-3 Curve 8 0.3-0.5 1-3 Curve 9 0.2-0.3 1-2

[0104] Step 6: Conduct a hermeticity test according to Method 1014 of GJB 548B - 2005 under Test Condition A4. The test results are all less than 1×10 - 9 Pa·m3 / s.

[0105] Step 7: Conduct 100 temperature cycles from - 65°C to 175°C according to Condition F of Method 1010 of GJB 548B - 2005. After the temperature cycle, measure the hermeticity results, which are all less than 1×10 - 9 Pa·m3 / s. This test proves that the soldering effect of these 9 groups of experiments is good.

[0106] Step 8: Statistical conclusion: According to the experimental results, after pre - treating the components according to Curve 3, the soldering effect of the relay encapsulation shell is good, and the solder spreadability is effectively controlled. Under the condition of ensuring the soldering effect, the present invention effectively controls the spreadability of silver - copper solder during soldering, improves the soldering performance and the reliability of the product.

[0107] Such as Figure 8 、 9As shown in the figure, the metal shell relay of Embodiment 3 includes a shell 34 with an electrical module installed in its inner cavity and a printed circuit board for installation, which can provide support. Small-sized shells can be fabricated by methods such as cold pressing, blanking, and splicing welding. The metal has good thermal conductivity for timely heat exchange to prevent components from overheating. At the same time, the accumulated static electricity inside is output to avoid component breakdown or short circuit. It has good rigidity and elastic memory. The cover plate 33 is hermetically fastened to the shell 34 and adopts a split structure with reasonable design. A process through-hole 35 is provided on the cover plate 33 for convenient installation. The bottom welding bracket 36 with mesh holes is hermetically welded to the inner side wall of the cover plate 33 and is located directly below the process through-hole 35, and its pre-installation realizes the support of the water-repellent and breathable membrane. The upper gap diaphragm 37 is arranged on the bottom welding bracket 36 and is located below the process through-hole 35. The water-repellent membrane 38 is located in the process through-hole 35 and above the upper gap diaphragm 37. The upper pressure grid 39 is installed on the cover plate 33 by bolts. The gap diaphragm with the same structure as the upper gap diaphragm 37 is arranged between the upper pressure grid 39 and the upper gap diaphragm 37. The gap is adjusted through the diaphragm to ensure flexible contact on both sides of the water-repellent membrane, thus preventing it from being suspended. The water-repellent membrane will not deform due to pressure changes, and the force is transmitted through the diaphragm, so the water-repellent membrane is stressed, with reasonable design.

[0108] The sum of the thicknesses of the upper gap diaphragm 37, the water-repellent membrane 38, and the gap diaphragm is greater than the depth of the process through-hole 35, thus realizing pressure contact on the upper and lower surfaces. The pore diameter of the water-repellent membrane 38 is smaller than the diameter of water molecules, allowing gas molecules with a diameter smaller than water molecules to enter, thereby ensuring the dryness inside the shell and preventing components from getting damp. The present invention solves the long-term technical problems that have plagued metal packaging, solves the problem of unbalanced internal and external pressures, and avoids the deformation of thin shells due to pressure changes, resulting in leakage of the sealing performance under pressure differences.

[0109] The thicknesses of the upper gap diaphragm 37, the water-repellent membrane 38, and the gap diaphragm are selected according to the depth of the process through-hole 35 to ensure pressure contact on the upper and lower surfaces of the water-repellent membrane.

[0110] A filter is externally connected to the upper pressure grid 39, and a filter is externally connected to the filter, thereby realizing pre-filtration and preventing the water-repellent membrane from adhering to debris in an unclean environment.

[0111] The shell 34 and the cover plate 33 are electroplated or sprayed with corresponding anti-corrosion layers according to the working conditions, with good versatility and expandability.

[0112] At the four corners of the bottom plate of the outer shell 34, there are U-shaped inlets 40, which facilitate the rapid entry and exit of bolts. Inside the U-shaped inlets 40, there are process side flanges 41 with a width greater than that of the U-shaped inlets 40; the U-shaped inlets 40 and the process side flanges 41 form a mushroom-shaped gap. On the inner side walls and the upper and lower surfaces of the process side flanges 41, there are injection-molded linings 42 for connecting bolts, so as to use the small-width inlets to prevent the plastic linings from detaching from the openings and also prevent detachment from the upper and lower surfaces. At the same time, the plastic linings are used to cut off the transmission of static electricity or leakage.

[0113] As an introduction to the circuit, the electrical module includes a printed circuit board 31 that is electrically connected to each other and is arranged on the bottom plate of the inner cavity of the outer shell 34; on one side of the printed circuit board 31, there are welded or inserted power components 32, and the other side of the printed circuit board 31 is a copper-clad area.

[0114] Preferably, the power component 32 includes an isolation input module, a zero-crossing detection module (which can be a general circuit), and an output circuit module that are electrically connected in sequence; the input circuit of the isolation input module uses a constant current source control method, and the input voltage range is 6VDC - 32VDC; the zero-crossing detection module uses an optocoupler; the output circuit module as the power output includes multiple reverse-parallel unidirectional thyristors, and an RC absorption circuit is electrically connected across the unidirectional thyristors.

[0115] For example, a relay designed for a certain deep-sea submersible, a high-power metal hermetic three-phase solid-state relay with a designed current of 10A, wide voltage input, isolation detection, zero-voltage conduction, zero-crossing region of ±15V, built-in RC absorption circuit, more reliable operation, and the maximum size is only 66mm × 33mm × 17mm. The volume of the present invention is much smaller than the design of the metal hermetic structure of high-power three-phase solid-state relays of the same type in the market.

[0116] Preferably, in principle, this module is a DC input - AC output type module, and the circuit mainly consists of three parts: an isolation input module, a zero-crossing detection module, and an output circuit module. The input circuit uses a constant current source control method, and this input circuit can be applicable to a relatively wide input voltage range; the zero-crossing detection module circuit uses an "opto-coupler", which is sensitive in operation, high in response speed, and high in the isolation withstand voltage level between the input / output terminals; the output circuit module uses six reverse-parallel unidirectional thyristors as the power output, and an RC absorption circuit is designed across the thyristors to suppress surge voltage and improve the static dv / dt index.

[0117] The present invention designs a high-power metal hermetic three-phase solid-state relay with a designed current of 10A, wide voltage input, isolation detection, zero-voltage conduction, zero-crossing region of ±15V, built-in RC absorption circuit, and more reliable operation.

[0118] The volume of the present invention is much smaller than that of similar products (about one-seventh of the volume of the same type), saving a large amount of installation space for users; the all-metal hermetic package can adapt to harsher application environments.

[0119] Structurally, a new all-metal hermetic structure is designed, with legs on the side, the power components are sintered on the metal shell, and the control part is fixed on the power part using a PCB, greatly reducing the volume.

Claims

1. A manufacturing method of an encapsulated metal shell relay, characterized in that : First, fabricate the metal oxide layer of the ceramic insulator (63); then, weld the ceramic insulator (63) to the housing (34) through the metal oxide layer. In the step of fabricating the metal oxide layer of the ceramic insulator (63), the following steps are carried out; Step I: Select a graphite plate (61); Step II: Machine a groove (62) at the center of the graphite plate (61); Step III: Select a ceramic insulator (63) and place it in the groove (62), with the ceramic insulator hole placed parallel to the groove of the graphite plate (61); Step IV: Place a solder (64) with a diameter of Ag72Cu28 above the ceramic insulator (63); Step VI: Place a 4J42 nickel-plated cover plate (65) above the Ag72Cu28 solder (64); Step VII: First, bend and shape the molybdenum sheet (66); then, fix the bent molybdenum sheet (66) to the graphite plate (61); Step VIII: Place the workpiece of Step VII in a gas-protected sintering furnace for sintering; Step IX: Take out the sintered ceramic insulator (63), pull the ceramic insulator (63) with a preset force. If the ceramic insulator (63) separates from the 4J42 nickel-plated cover plate (65), the firmness is poor; otherwise, the firmness is good.

2. The manufacturing method of the encapsulated metal shell relay according to claim 1, characterized in that : In the process of welding the ceramic insulator (63) to the housing (34) through the metal oxide layer, the specific steps are as follows: Step A: Clean the surfaces of the ceramic insulator (63) and the housing (34) to remove impurities; Step B: Electroplate the housing (34) with nickel; Step C: Place the housing (34) in a nitrogen-protected furnace and perform pretreatment in groups; Step D: After assembling the housing (34), perform brazing; Step E: Visually inspect and measure under a microscope to count the solder fluidity.

3. The manufacturing method of the encapsulated metal shell relay according to claim 2, characterized in that : Before or after welding the ceramic insulator (63) to the housing (34) through the metal oxide layer, encapsulate the metal housing relay assembly in the installed housing (34); including the following steps, Step One: First, install the printed circuit board with installed electronic components (31) on the housing (34); then, install injection-molded gaskets (42) at the U-shaped inlets (40) at the four corners of the housing (34); Step Two: First, install the bottom welding bracket (36) in the process through-hole (35) of the cover plate (33); then, place an upper clearance diaphragm (37) on the bottom welding bracket (36); secondly, place a water-repellent membrane (38) on the upper clearance diaphragm (37); thirdly, fit a clearance diaphragm on the water-repellent membrane (38) so that the upper surface of the clearance diaphragm is higher than the upper port of the process through-hole (35); immediately afterwards, install an upper pressure grid (39) on the clearance diaphragm.

4. The manufacturing method of the encapsulated metal shell relay according to claim 1, characterized in that : By means of a manufacturing system for encapsulating a metal shell relay, which includes a metal shell relay with a shell (34) having an electrical module installed in its inner cavity, a graphite plate (61) is provided on the shell (34), grooves (62) are machined on the graphite plate (61), ceramic insulators (63) are placed in parallel in the grooves (62), a 4J42 nickel-plated cover plate (65) is provided on the graphite plate (61) above the ceramic insulators (63), Ag72Cu28 solder (64) with a diameter of 2.7 mm is placed above the ceramic insulators (63), a 4J42 nickel-plated cover plate (65) is placed above the Ag72Cu28 solder (64) above the graphite plate (61), and a bent molybdenum sheet (66) is provided between the 4J42 nickel-plated cover plate (65) and the graphite plate (61).

Images