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Refrigeration Compressors (RC) using

Dynamically Variable Stroke Technology” (DVST)  

When applied to refrigeration compressors The Dynamically Variable Stroke Technology allows the compressed volume to be varied while the pump is running.

Examples of typical designs for this application are :

  1. The ball bearing DVST—applied to small cylinder compressors.

  2. Replacing swash plate multi cylinder (usually 5 cylinders or more) compressors used in motor vehicle airconditioning with single cylinder variable stroke type – 1/5 the cost to produce and maintenance (approx)

  3. The journal or roller bearing DVST- applied to large multi-cylinder compressors


  1. Varying the volume of the compressors allows sizing the compressor and it running power to a minimum saving energy.

  2.  Dynamically Variable Stroke Technology saves energy in refrigeration.

  3.  Refrigeration technology has become more efficient since the introduction of electronic speed control of motors (inverters) allowing the units to run at speeds, hence capacity, that conditions demand.

  4. The marketing of this improved approach can demonstrate a vast improvement in efficiency over on—off technology previously used.

  5. The additional electronics however has approximately a 10% loss of efficiency and it has another expensive component requiring maintenance.

  6.  The Dynamically Variable Stroke Technology achieves variable delivery with a greater range ( zero to Maximum) than  the inverter technology without the 10% energy losses in electronics.

  7. Manufacturing costs are similar less.

 Introducing Dynamically Variable Stroke Technology to all refrigeration  applications, sealed and open units, can introduce approximately another 10% reduction in energy usage over the latest technology, the “Inverter”.

Resulting in less electrical power being used – less global warming, pollution, running costs and less fossil fuel used.