The continuing trend towards miniaturisation has revolutionised the assembly of electronic components. For the past 15 years, most components have been secured directly to the pcb surface by means of Surface Mount Technology (SMT). By dispensing with drilled holes on the pcb, a space saving of up to 70 percent is achieved.
Today, typical components such as resistors, ICs, capacitors, and connectors with straight terminal pins are almost exclusively fitted using SMD (Surface Mount Device) technology in mass production. In contrast, angled SMD connectors at the edge of the board have not been successful because of tolerance problems (co-planarity) and stresses during mating. Modified solder connectors for assembly with “Pin in Hole Intrusive Reflow” process offer a better solution. These can be mounted at low cost, utilising existing SMD production lines.
SMT board with connector for "Pin in Hole Intrusive Reflow" assembly
"Pin in Hole Intrusive Reftow"
In this process, the connector is inserted into plated through holes in a comparable way to conventional component mounting. All other components can be assembled on the pcb surface.
The components are positioned using pick-and-place machines. These automatic assembly machines differ according to whether the components are small, lightweight or bulky. Connectors are considered bulky (odd form) because of their comparatively heavy weight and large volume which makes them more difficult to grip. Furthermore, machines for odd form components must have higher insertion power to fit the components into pcb holes, which are filled with solder paste. As a rule, modern SMC production lines are equipped with both types of machine, therefore the “Pin in Hole Intrusive Reflow” process generally entails no extra investment costs for the user.
Conventional assembly process:
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1. Application of solder paste |
"Pin in Hole Intrusive Reflow
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1. Application of solder paste | |
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6. Quality inspection |
see also:
New cost saving assembling techniques
SDSRS advantages