Both liquid and gas linear pumps utilize electromagnetism to apply force to a diaphragm or piston to positively displace air or pump liquid. Alternating current in electrical coils reverses the magnetic field induced around a magnetized rod at a rate determined by the supplied frequency. Movement of the diaphragm or piston attached to the end of the rod forces air through one-way valves. Linear diaphragm pumps are equipped with linear magnetic and vibrating armature motor types
Linear pumps also called vibrating armature pumps are quiet and efficient. They have fewer wearing parts than equivalent reciprocating pumps. Thus linear compressors are regarded as long-life and low-maintenance devices. However, their pneumatic performance is limited to the strength of the induced magnetic field, making them suitable for low differential pressure applications.
These positive displacement pumps are used in sewage aeration, greywater treatment, aquaculture, and pond aeration, just to name a few environmental applications. Equally often they are the right choice for various OEM medical devices such as for inflating air mattresses or for compression therapy devices.