Technology
The Linear-motor-driven Free Piston System (Pat.) has an internal piston
inside the cylinder which is driven by an electro-magnet and spring system
controlled by the alternating input current cycle. The piston thus forms
a single combined structure of two usually different devices; motor and
pump. The system is quiet and vibration free, and offers the advantages
of easy maintenance and a long operating life.
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Linear
Pump Operating Principle
 The
activated electro-magnet attracts the piston against the return spring,
while air is taken into the cylinder through the opened inlet valve.
When the electro-magnet is deactivated, the return spring pushes the piston
back, and the compressed air is brought out of the cylinder through the
now open outlet valve.
The system
can function as either an air compressor or as a vacuum pump.
Fewer
Components
 The
pump's unique and simple structure has no complicated transmission mechanism
such as a crankshaft, connecting rods, ball bearings, etc., which are
widely used in between the motor and compressor in conventional pumps.
Easy
Maintenance
Replacement
of the piston is easily achieved by simply removing the end cap connected
to the pump housing by unscrewing the four screws which hold the cap in
place. Completely oil free construction is achieved by the combination
of smooth Teflon® seals with superior resistance against abrasion
on sliding piston surfaces and the "air bearing effect" created
by the unique air path design.
Features of the Linear-motor-driven Free Piston System:
- Self-cooling
design.
Cool intake air is blown onto the electro-magnetic coils through an
orifice, making sealed construction possible and preventing the escape
of operating noise.
- Low
noise level.
The machine has no complex transmission system. This results in the
lowest noise level possible due to the absence of rotating parts or
ball bearings. Operating noise is also quelled due to the pump's sealed
configuration.
- Small
output air pulsation.
Piston reciprocation is synchronised with input power frequency regardless
of load (i.e.; 3000 rpm for 50Hz and 3600 rpm for 60Hz). Such high RPM
adversely reduces each discharge volume and eliminates any problems
caused by pulsation.
- Low
Power Consumption.
The piston is the only component in the system which moves. The absence
of transmission usage to pass the power to the piston means that there
is a large reduction in energy loss, and an improvement in efficiency
over other pumps.
- Compact
composite structure.
This unique system enables direct reciprocation of a single part which
consists of composite piston and armature. The incredibly compact and
lightweight design was achieved by combining what are two different
functions in other pumps - motor and piston - into a single structure.
- Anti-overpressure
mechanism.
When the output pressure exceeds the rated value the piston stroke will
automatically diminish and prevent over-pressurising. At the same time,
the current and power consumption will also be automatically reduced,
thus eliminating possible failure caused by tentative overload.
- Low
vibration.
The aluminium die-cast piston produces very little vibration or kick-backs.
Little or no damage from vibration stress is therefore sustained during
operation. Even secondary vibrations are absorbed by special soft rubber
feet.
- Quick
Response.
Due to the lower starting current, the unit can immediately respond
to frequent on-off input signals, even under back pressure
conditions.
- Longer
Durability.
Oil free construction requires no periodical oil-up. This simple mechanism
has the fewest number of moving parts possibe; one. Long and stable
performance is assured if usage complies with its specification.
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