US Patent 7263838 - MEMS flow control for refrigerator

http://www.freepatentsonline.com/7263838.html

This patent from Raytheon teaches using microelectromechanical actuators for more dynamic flow control in refrigerator operation. Claim 1 reads:

1. A regenerative refrigerator comprising: a compressor; a regenerator coupled to a downstream end of the compressor; a pulse tube coupled to a downstream end of the regenerator; and a MEMS flow controller for controlling flow within the refrigerator.