Electromagnetic pump single/double wave crest generator

Abstract

Said invention belongs to welding equipment, especially automatization welding equipment suitable for PWB printed wiring board in surface mounting technology (SMT). It contains an electromagnetic pump type single / double wave crest generator consisting of single side type linear motor primary stator core and winding, magnetism shielding plate, liquid metal container, pump mouth etc, wherein said liquid metal container is T-type structure, longitudinal part of T-type structure having plurality of symmetric longitudinal channel whose one end communicated with pump mouth, another end communicated with container, both sides of liquid metal longitudinal part having two linear motor stator core with winding, electromagnetic pump having two pump mouth, respectively connected with two symmetric pump channels, channel mouth size is less than size of channel body and adopting magnetic wedge fixing winding. Said technology forms electromagnetic pump type single / double wave crest generator with smoothness reliable wave crest.

Description

【Technical field】 [0001] The invention belongs to the field of welding equipment, and is especially suitable for automatic welding equipment of printed circuit boards in surface mount technology (SMT). 【Background technique】 [0002] With the popularity of electronic equipment, the production of circuit boards as the main components continues to increase. In the production and processing of circuit boards, in addition to the quality of electronic components, the most important problem is the quality of welding during processing. Nowadays, liquid metal soldering electromagnetic pumps are usually used to solder circuit boards, but in the above-mentioned large equipment, the wave peaks generated by the equipment are not stable and reliable during the working process, which affects the quality of welding. The current patent US-3797724 and the liquid metal soldering electromagnetic pump of CN8620924U all belong to the conductive electromagnetic pump. The disadvantage is that the ...

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Problems solved by technology

Nowadays, liquid metal soldering electromagnetic pumps are usually used to weld circuit boards, but in the above-mentioned large equipment, the wave peaks generated by the equipment are not stable and reliable during the working process, which affects the quality of welding.

The current patent US-3797724 and the liquid metal soldering electromagnetic pump of CN8620924U all belong to the conductive electromagnetic pump. The disadvantage is that the circuit resistance is changed by the influence of the liquid high-temperature metal oxide slag, and the circuit resistance directly affects the size of the circuit current, thereby The electric power (F=BIL) is directly affected, resulting in unstable wave peaks, and even large fluctuations in wave peaks. The current solution to this problem is to use a high-temperature anti-oxidation oil protection system, which requires high-temperature oil at a temperature of 250-300 degrees. No carbonization, no volatilization, and no decomposition under long-term work. The high-temperature oxidized oil is not only expensive, but also in short supply; patents CN932468993 and CN910581262A are both single-phase electromagnetic induction single / double peak liquid metal electromagnetic pumps. The principle is to use the inner and outer rings of electromagnets The difference in the magnetic circuit produces a phase difference, and then forms a moving magnetic field from the leading phase to the lagging phase, and generates a corresponding induced electromagnetic thrust to form a wave peak

The disadvantage is that although the wave peak instability problem caused by the influence of liquid high-temperature oxidized slag has been solved in the conduction electromagnetic pump, most of it is a useless pulse vibration magnetic field with serious harmonic components, low electromagnetic conversion efficiency, and poor uniformity of electromagnetic force. Small, unable to obtain stable high peak and large peak width; patent CN962366223.9 electromagnetic pump double peak generator, the electromagnetic pump must be installed on both sides of the solder bath to reduce the interference of electromagnetic coupling, but this will cause the volume of the wave generator Large, it is difficult to interchange with the mechanical pump wave generator; although the patents CN962366223.9 and CN2429290Y reduce the interference of electromagnetic coupling, the solder in the pump cavity is not easy to heat, which increases the heating power or tin melting time; the grooves of the two The mouths are large, which affects the continuity and uniformity of the magnetic field

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