05342176 is referenced by 100 patents and cites 2 patents.

A method of measuring the distance at closest approach between the piston of a free piston compressor and the cylinder head. The method derives measurements of both the alternating and average components of piston position from direct measurements of the voltage and current applied to the linear permanent magnet motor that drives the piston, and thus eliminates any requirement for an additional position sensor located within the compressor.

Title
Method and apparatus for measuring piston position in a free piston compressor
Application Number
8/42662
Publication Number
5342176
Application Date
April 5, 1993
Publication Date
August 30, 1994
Inventor
Robert W Redlich
Athens
OH, US
Agent
Frank H Foster
Assignee
Sunpower
OH, US
IPC
F04B 49/00
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