SMT Pick-n-Place System
Revision as of 07:55, 27 March 2011 by ErikDeBruijn (talk | contribs)
A fully fledged SMT Pick-and-place system requires:
- Grippers or a picking toolhead (see below or see Gene Hacker's toolhead)
- PCB holder(s) (see below this page)
- Component feeders
Optional subsystems include:
- Vision systems for compensating for variations in the pick-up of a component, and for detecting correct placement, calibrating against the circuit board dimensions, etc.
Contents
Grabbing parts
Options are:
- Most gripper types rely on suction
- Mechanical grippers
- Ferromagentic parts (e.g. most resistors) can be grabbed with an electro-magnet.
Grippers
Vacuum grippers
Possible vacuum sources:
- A printed pump (such as this one by Madox, or this one)
- Peristaltic pump (such as Zach's)
- A positive pressure based on the Venturi-effect (can be printed)
- Simple off the shelf USB-vacuum
- A piston that is actuated with a motor (lego, fishertechnik, etc.).
Rubber vacuum tips:
Mechanical grippers
Magnetic grippers
Video (note: downloads a 6mb file)
Holding the PCB
- These kinds of studs with magnets are useful for holding PCBs.
Other operations
Circuit making
If a circuit could be printed or milled in the same machine, this would save you setup time. This is discussed at: Pick-n-Place Feeders. See also: Printing electronics.
Reflow soldering
Usually reflow is done in a controlled oven and the temperature should follow a specific curve. This is to prevent sensitive devices such as LEDs from overheating and to still properly reflow the paste at every solder joint. However, I (Erik) have good experiences with a hot air stream that can be fed from the toolhead, meaning that you can also reflow the boards in the same machine.
