57results about How to "Avoid poor soldering" patented technology

The invention discloses a low-temperature lead-free solder alloy, containing larger than or equal to 30% of and smaller than or equal to 60% of Bi, larger than 0.001% of Si and smaller than or equal to 0.02% of Si, as well as microalloy elements (alterant), rare earth elements, antioxidant elements and the balance of Sn and inevitable impurities. The large crystal grains of a Bi phase in a traditional Sn-Bi alloy system and the problem of reliability of brittle rupture of a welding joint is caused by that Bi is segregated at a Cu/Cu3Sn interface to form a brittle Bi layer in a long-term service process of the traditional Sn-Bi alloy system are effectively improved, and the mechanical impact and falling resistance of the traditional Sn-Bi system alloy can be greatly improved.

The invention provides an element mounting device and an element mounting method. The element mounting device comprises a head assembly and a control part. Elements are installed on a substrate by the head assembly. The motion of the head assembly is controlled by the control part. Meanwhile, the mounting position of elements is adjusted according to the printing offset of the solder with respect to the electrode. When the printing offset is within a correction permissible range, the elements are installed on the substrate with the offset position of the solder on the substrate as a reference. The correction permissible range is set according to the self-correction effect exhibited by the fused solder, so that the mounting position of the elements is corrected to be at the electrode side. When the printing offset exceeds the correction permissible range, the elements are installed with the specified position close to the electrode as a reference within the offset range of the solder on the substrate. Therefore, the mounting position of the elements is adjusted according to the offset, so that the bad welding is prevented and the elements are satisfactorily installed on the substrate.

The present invention relates to a thermal expansion valve. It includes the following several main portions: valve core, diaphragm, air tight chamber and seal head. Said invention also provides the concrete structure of the above-mentioned every portion and the connection mode of all the above-mentioned portions. Besides, said also provides the concrete working principle of said thermal expansion valve and its concrete application method.

The invention belongs to the technical field of printed circuit board manufacture, and relates to a PCB character process. The PCB character process comprises the steps of soldering resisting developing, A-surface printing, A-surface baking, B-surface printing, soldering resisting baking and cutting molding. Compared with prior art, the PCB character process has advantages of reducing a technological flow, reducing production time, realizing remarkable delivery time advantage, reducing heating time, reducing energy consumption, reducing exhaust processing cost, satisfying a low-carbon development requirement, preventing defective welding caused by pollution in multiple time of board baking, and improving product reliability.

The invention discloses a stainless steel welding rod and a manufacturing method thereof. The stainless steel welding rod comprises a metal welding core and a covering, wherein the metal welding core comprises a working part and a clamping part which are fixedly connected; the working part and the clamping parts have same diameter; the working part is an iron alloy wire; the clamping part is an aluminum-magnesium alloy wire; the working part comprises the following components in percentage by weight: smaller than or equal to 0.03 percent of C, 0.4-1.2 percent of Mn, 0.5-1.0 percent of Si, 13-15 percent of Cr, 5-6 percent of Ni and the balance of iron and inevitable impurities. According to the method, the working part and the clamping part are in friction welding to form the welding core, and the outer surface is coated with the covering. The stainless steel welding rod can realize automatic separation of the clamping part and a weld joint. The material of the covering of the working part is improved to be more suitable for welding of stainless steel to adapt to welding of various containers and pipelines in the fields such as chemical industry, energy sources and foods.

The invention discloses a power battery precise welding device. The device comprises a rack, and further comprises two shifting mechanisms, two welding fixtures, two distance measuring modules and twowelding modules, wherein the two shifting mechanisms are movably mounted on the rack, and can be alternately positioned at a welding station and a discharging station; the two welding fixtures are installed on the two shifting mechanisms correspondingly and used for power battery clamping and positioning; the two distance measuring modules are installed on the two welding fixtures correspondinglyand used for measuring the distances between the distance measuring modules and the end faces of a power battery clamped in the welding fixtures; and the two welding modules are installed on the twosides of the shifting mechanisms correspondingly and carry out welding on the power battery in the welding fixtures simultaneously according to the measurement values of the distance measuring modules. A power battery precise welding method is also disclosed. According to the welding device and the welding method, a shell with low manufacturing precision and large self-deformation can be accurately positioned, and effective inspection and elimination of defective products after welding can be realized.

The invention provides a surface mount structure used for fixedly mounting an electronic element with a pin and a welding chassis onto a circuit board. The surface mount structure comprises a pad formed on the circuit board, wherein the pad comprises a first pad welded with the bottom surface of the pin, a second pad welded with the bottom surface of the welding chassis and a connecting wire for connecting the first pad and the second pad. The structure is characterized in that the area of the surface of the second pad, which is opposite to the bottom surface of the welding chassis, is larger than the area of the surface of the first pad, which is opposite to the bottom surface of the pin; the space between the first pad and the second pad is smaller than 0.3mm; the connecting wire comprises a current-limiting part and a non-current-limiting part; the current-limiting part is connected with the first pad, and the non-current-limiting part is connected with the second pad; and the partial or overall wire width of the current-limiting part is smaller than the wire width of the non-current-limiting part.

The invention discloses an integrated water path member and a water purifier. The integrated water path member comprises a member body, wherein a plurality of filtration core straight flow channels capable of extending forward and a plurality of control valve straight flow channels capable of extending downward are formed in the member body, the filtration core straight flow channels are used forconnecting the filtration core of a water purifier, and the control valve straight flow channels are used for connecting the control valve of the water purifier. With the technical scheme of the present invention, the assembly efficiency of the water purifier can be improved.

The invention discloses a duplex metal welding rod and a manufacturing method thereof. The duplex metal welding rod comprises a metal core wire and a coating, the metal core wire comprises an operating part and a clamping part which are fixedly connected, the diameter of the operating part is the same as that of the clamping part, the operating part is made from iron alloy wires, the clamping part is made from aluminum magnesium alloy wires, and the atomic ratio of aluminum and magnesium in the aluminum magnesium alloy wires is 3:2. The method comprises the steps of welding the operating part and the clamping part to form the core wire in a friction way, and coating the coating on the outer surface of the core wire. According to the duplex metal welding rod provided by the invention, the clamping part and a welded joint can be automatically separated; furthermore, the aluminum magnesium alloy is served as the clamping part, on one aspect, the clamping end planes of soldering pliers have good conductivities; meanwhile, spinel phase welding slag of MgO (Magnesium Oxide) and Al2O3 (Aluminum Oxide) is formed on a bonding interface of the clamping part when the total operating part is molten in the welding process, and the duplex metal welding rod has a stronger separating capacity from the welded joint of a molten state.

The invention relates to the technical field of a DC plug, and particularly relates to a DC plug metal contact and a metal contact flat cable capable of automatically crimping. According to the DC plug metal contact, a half-ring-shaped contact plate and an inner elastic contact plate are connected with transverse connect plates through two connect plates, the connect plates are provided with wire riveting positions near the position of the transverseconnect plates, when the DC plug is produced, an interpolation core formed by the metal contact is arranged inside an insulation coat shell in an inserting mode, and the half-ring-shaped contact plate is in contact with a bare contact part of the coat shell. Two wires which are required to be connected are crimped on the riveting positions of the connect plates of the half-ring-shaped contact plate and the inner elastic contact respectively through an automatic crimping machine, and the two wires are cut on the transverseconnect plates, so that the tight connection is assured, quality problem caused by traditionally welding is avoided, and production efficiency is improved. When a DC plug flat cable is formed by a whole chain of transverse connect plates, the transverse connect plates can be formed into a tray and can be arranged on the crimping machine to automatically crimp the wires, and work efficiency is improved.

The invention discloses a copper clad welding rod and a manufacturing method thereof, wherein the copper clad welding rod comprises a metal core and a welding flux covering; the metal core comprises a working part and a holding part that are fixedly connected with each other; the welding flux covering is covered outside the working part; the working part is an iron alloy wire; and the holding part is a copper-plated aluminum wire; the length ratio between the holding part and the working part is 1:7-8; and the welding flux covering comprises the following components: 20-25 parts by weight of albite, 10-12 parts by weight of potassium carbonate, 6-10 parts by weight of calcium carbonate, 20-25 parts by weight of sodium silicate, 1-3 parts by weight of nanometer titanium dioxide, 2-3 parts by weight of nanometer ferric oxide, 1-1.5 parts by weight of manganese dioxide, 0.5-1 part by weight of rare earth lanthanum, 8-12 parts by weight of kaolin, and 6-10 parts by weight of Zuoyuntu (a raw material for electroceramics originating in Zuoyun County, Shanxi Province, China). The method comprises the steps of frictionally welding the working part with the holding part, and then coating the welding flux covering. By employing the contact interface design of the working part and the holding part of the welding rod, and utilizing the different characteristics of the metal and the welding flux covering, automatically releasing the welding rod head is achieved when the welding rod is about to run out, thereby thoroughly avoiding the residual of the welding rod head.

The invention relates to the design field of a circuit, and particularly relates to an automatic mounting and tin block addition-based through hole reflow soldering. By applying automatic mounting andtin block addition-based through hole reflow soldering, a tin block material is loaded by a braided band, so that automatic material taking and tin block mounting and adding are realized; and the problems of less tin and poor soldering caused by the generated tin balls in the through hole reflow soldering are solved, reliability of through hole reflow soldering is improved, the processing qualityof a PCBA board is improved, the repair cost in manpower tin-supplementing soldering is lowered, and the hidden risk of short circuit caused by tin ball residue is eliminated.

The invention discloses a mobile phone camera module welding and fixing device and a welding and fixing method thereof. The mobile phone camera module welding and fixing device comprises a base and atray mechanism connected with the base and used for fixing the camera module before welding, the tray mechanism comprises a tray support and multiple fixing strips capable of synchronously rotating, two ends of the fixing strips are rotatably connected with the tray support, a transmission part enabling the fixing strips to synchronously rotate is arranged at the same ends and is provided with anopening, and the opening is matched with an eccentric wheel or swing arm connected with a driving motor. During use, through the transmission part, all modules fixed to the fixing strips synchronouslyrotate by the specific angle for welding, after welding, the modules are taken out. Due to the fact that the fixing device enables the modules to synchronously rotate by the same angle, as long as during setting, the module fixing angles are adjusted, it must be ensured that the deviation angles of modules at the welding station are same, poor welding caused by different angles can be avoided, and the welding efficiency is improved.

The invention belongs to the technical field of laser welding, and relates to a pressing cylinder structure and laser welding equipment. The laser welding device is applied to laser welding of a power battery module and comprises a first pressing cylinder, a cover plate and a second pressing cylinder. The second pressing cylinder is arranged at the bottom of the first pressing cylinder, an air inlet is formed in one side of the first pressing cylinder, the cover plate is arranged on the side, located on the air inlet, of the first pressing cylinder, and an air channel is formed among the first pressing cylinder, the cover plate and the second pressing cylinder. The air channel is communicated with the air inlet, air outlets are formed in the lower end of the first pressing cylinder and the lower end of the second pressing cylinder, the air inlet is used for blowing in protective gas, and the protective gas passes through the air channel and is blown out of the air outlets. The shielding gas can cover each welding area more uniformly, so that each welding area is protected more comprehensively, the situations that a welding object splashes and the surplus height of a welding seam is too high during welding are well reduced, the welding effect is improved to a great extent, and the welding object is more attractive after being welded.