What is the swing motor?
Usually, the dynamic power source for compressor is an electric motor of which main axis rotates. The swing motor is a vibration type in which the coil directly connected to the compressor (piston) moves reciprocally.
When an AC current is applied to a coil placed at right angle to the magnetic field, a thrust occurs according to Fleming's left hand rule. This thrust is directly applied to the piston, which then performs the compression and intake cycles.
・Resonance of the piston
To compress the gas only with the piston connected directly to the thrust generated from the coil, the amplitude is not sufficient. For this reason, to compress the refrigerant effectively, the swing motor synchronizes the frequency of input current with the specific frequency of oscillating system consisting of the piston, coil and spring so that the resonance occurs. Using this resonance phenomenon, the amplitude is increased for the compression of refrigerant.
・Low starting power structure
The swing motor has a structure of directly transmitting the thrust of the coil to the piston. Therefore, it can start even if the piston does not complete the full stroke. That is, no large starting force is required.
Moreover, unlike a rotary type, there is no inrush current at the time of start, the consumption of battery power is low and it is not necessary to use wiring with thick cables.
In order to obtain the maximum efficiency using the resonance phenomenon of a spring, it is necessary to carry out the precise frequency control.