SMT & Inspection |
Speedline “Streams" Ahead with New SmartStream™ Dispense Technology
Needle-based dispensing is a widely-used method that is well-suited for many applications. For certain requirements, however, Speedline Technologies is introducing a unique new non-contact technique, known as “streaming," that will be available on select Camalot dispense systems.
This innovative method offers distinct advantages through its use of positive displacement technology to optimize volume repeatability and maximize material flow rates, resulting in an extremely fast and accurate alternative to jetting. Operation of the patent-pending SmartStream pump totally eliminates striking of a piston to a seat or nozzle, significantly reducing the replacement interval of these parts and providing very quiet operation.
Each cycle of the pump displaces a column of material, rather than a single sphere. In operation, the unit cycles at frequencies that create a “stream" of material that can deliver increased flow rates (greater than 70 µl/sec). The displacement piston, driven by a linear motor/encoder assembly, is carbide, so it is extremely wear resistant. The design of the pump unit allows for easy removal and cleaning of the fluidic module that contains all wetted parts. Only three o-rings need to be replaced, so downtime and cost of ownership are minimal, with consumable costs less than $1 per day. This technology, to be released by Speedline in July, will enable increased dispense rates especially, with underfill applications.
For processes currently using non-contact dispensing, the primary throughput benefits come from two areas. First, Z travel of the dispense head is virtually eliminated as material is released from a nozzle 2-3 mm above the PCB surface. Needles, on the other hand, are typically 0.25 mm above the surface and require Z motion to snap off the material from the tip and to clear any obstructions in moving to the next location. The second area where productivity gains are made is in reducing the number of height senses needed to perform the dispense operation. Needle height above the substrate is critical in order to maintain a reliable process. For underfill, height sensing might be performed once for each component, be it a Flip Chip, CSP or BGA. Dispense height is less critical for streaming, since the technology is much more forgiving and only needs a single reference height measurement, further reducing cycle time.
SmartStream technology was well-received during its recent preview at the IPC's APEX® trade show in Los Angeles. The SmartStream pump will be available beginning July 9, 2007 on new Camalot XyflexPro+, XyflexPro DLM and FX-D dispensing platforms, and will be field retro-fittable to existing systems.
