04829957 is referenced by 20 patents and cites 8 patents.

A gaseous fuel injection system for internal combustion engines features a "variable-pressure-controller" which translates a varying negative pressure, sensed in the engine's air intake system by means responsive to the rate of flow of the intake air, into a proportionately varying amount of gaseous fuel at a positive pressure. That fuel is then injected into the engine's air intake system upstream or downstream of the throttle valve through flow restrictor means which cooperate with the variable-pressure-controller to provide an amount of fuel proportionate to the rate of air flow through the engine's air intake system. The invention is entirely mechanical-pneumatic in operation and readily adapted to a wide variety of liquid fueled engines, carbureted as well as fuel injected, or to one for gaseous fuel only.

Title
Gaseous fuel injection system for internal combustion engines
Application Number
7/217470
Publication Number
4829957
Application Date
July 11, 1988
Publication Date
May 16, 1989
Inventor
Keith H Garretson
Mt. Pleasant
IA, US
Owen L Garretson
Farmington
NM, US
Agent
Simmons Perrine Albright & Ellwood
Assignee
Garretson Equipment Co
IA, US
IPC
F02B
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