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The electro-mechanical industry is an environment where electronic and mechanical technologies integrate with the manufacturing
and assembly processes of the particular components. There are different ways to describe this separation of the industry into
various disciplines. Enimco has defined eight basic disciplines to make this subdivision. Each discipline has again a finer
subdivision on it's own. Basically any product produced by the electro-mechanical industry is built up by one ore more of
these eight components and processes:
Plastic Parts
Metal Parts
Standard Mechanical Parts
Standard Electronic Parts
Printed Circuit Boards
Cable Assemblies
Electronics Assembly
Mechanical Assembly
A large part of the components used to assemble an electro-mechanical product is made of plastic. Especially consumer products
use a lot a plastic parts because of the advantages plastic brings along. It's light weighted, rather cheap, easy to finish
with printing, it comes in many colours, it can be shaped into nearly any form , it isolates electricity etc. Housings, covers,
buttons, etc. are mainly made of plastic. But also components like connectors are mainly made out of plastic.
When a certain strength is required parts are made of metal. Housings, clips, etc can be made of metal. Industrial products,
which are subject to rough conditions, need to be more robust than consumer products and are typical applications for metal parts.
Metal is heavier than plastic and always need a coating to prevent oxidation, but is has, next to the material strength, other
advantages. When an electronic assembly is covered by a metal housing it's shielded for RF influences for instance.
It's obvious that because of it's conductive characteristics metal parts are widely used in several applications, e.g. connectors.
Besides the custom made plastic and metal parts a lot of standard mechanical parts, both plastic and metal, are used in assemblies,
like bolts, nuts, screws, spacers, pins, rivets, clips, rings, etc. These are available from different sources depending on the
required volume.
Most electronic components mounted on printed circuit boards are standard components and available from a catalogue. These are
components like resistors, capacitors, diodes, LED's, sensors, RAM chips, connectors, chargers, displays, etc. Next to these
standard components a board is populated by customised electronic components. Customised means in this case mainly a modified
standard component like an ASIC.
The printed circuit board (PCB) or printed wiring board (PWB) is the base for nearly any electro-mechanical product.
It's mounted with electronic components by various soldering processes. The PCB contains the circuitry of the product.
To connect various parts of an electro-mechanical product to each other or to external devices cable assemblies and wire
harnesses are used. Examples are standard and custom made power cords, patch cords, etc. but also very complex wire harnesses
which are custom made for the application where they are used in.
To mount the electronic components on the board various soldering processes are available. The most common and widely used
process today is the SMD (Surface Mount Device) soldering process. This is an automated process and is executed by a component
mounting machine. Devices are placed on the board by a pick-and-place unit and subsequently soldered to the board when the mounted
board is being lead through a reflow oven. The board can be mounted with components on both sides. Another process is through hole
or wave soldering. Components with pre-tinned legs are placed on the boards with the legs through the holes on the pcb. This can
be done by a pick-and-place but most of the time it's manual operation. Subsequently the board is lead through a so called wave
solder unit where the board touches a wave of solder with the bottom side of the board to make the components soldered to the board. Only one side of the board can be mounted with components. The third option is manual soldering. There are various reasons to choose for manual soldering, e.g. when relatively large components like cooling devices need to be mounted or when the second side of the board needs to be mounted with through hole components as well.
The last step in electronic assembly is the testing operation. Any board needs to be checked on manufacturing fault before it's
shipped or assembled in the final end-product.
The typical final process step when manufacturing an electro-mechanical product is the mechanical assembly. The printed circuit
board is placed into a housing, cable assemblies are connected, a final test can be executed, it need to be packed for shipping,
etc. This is a in most cases a manual operation and therefore labour intensive. Sometimes this process is semi-automated by the
use of conveyor systems to improve efficiency, but labour rates are always a critical item for this part of the process.
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