High pressure fuel supply system for natural gas vehicles

Abstract

This invention relates to a medium and high pressure liquid natural gas fuel system for internal combustion engines and for other cryogenic systems. A cryogenic pump comprising: (a) a vessel for containing compressed gas and liquid; (b) a first chamber in said vessel with an inlet therein for receiving gas and liquid; (c) a second chamber communicating with said first chamber for receiving and dispelling gas and liquid; (d) a third chamber communicating with said second chamber for receiving and dispelling gas and liquid; (e) a reciprocating means separating said first, second and third chambers from one another and for drawing and compressing gas and liquid in any one of the first, second and third chambers; (f) one-way inlet means for enabling gas and liquid to pass into the first chamber; (g) one-way means between said first and second chambers for enabling gas and liquid to pass from said first chamber to said second chamber; (h) one-way means for enabling gas and liquid to return from the second chamber to the first chamber; (i) one-way means between said second and third chambers for enabling gas and liquid to be passed from said second chamber to said third chamber; and (j) one-way means for enabling gas and liquid to be expelled from said third chamber to the exterior of the vessel. The invention also relates to a single action suction and double action discharge pump which can be readily removed from a confined space.