Remote metering for gaseous fuels and oxidizers

#This invention relates to a remote metering unit for an engine that is powered by liquid gasoline, liquid diesel, compressed propane, natural or other gas. This invention also relates to an engine allowing for the use of two or more fuels and/or fuels and oxidizers at the same time. Correct calibration of the remote metering unit will also allow the operation of a catalytic converter, an inexpensive hydrocarbon type, on a diesel engine.

#Compressed propane, natural and other gases are efficient fuels for providing for higher efficiency in powering engines. Such compressed gaseous fuels typically provide higher power at relatively low cost in a more reasonably environmentally friendly manner than liquid fuels alone. Advantages include lower wear on the cylinders and rings, cleaner burning and extended oil changes due to less oil consumption together with the dryness of the gas (and due to the fact that there is no oil wash off or dilution in the engine).

#Engine components for gas distribution, such as vaporizers/converters, fuel filters, fuel lock off are typically mounted adjacent to each other for use on existing engines. However, such components do not provide a total overall solution for the control of the combustion engines powered by such gaseous fuels; additional components are still required for these units. In addition, conventional supply of gaseous fuels to engines can result in higher emissions when the engine is warm as well as additional pressurized gas and hot water hose connections that can leak. In some instances a dual fuel operation is provided (propane for inside operation; liquid gasoline for outside operation). This necessitates two separate paths within/without a single unit. Emission control problems also remain substantially unsolved without the use of downstream treatment by multiple element catalytic converters and filters. A need still exists for a universal external, unitary fuel and/or oxidizer metering pod for internal combustion engines which can reduce the complexity of gas vaporization, and which can be retrofitted to existing liquid fueled engines. It would be desirable to provide for a precisely controlled metering pod for a compressed gaseous fuel and/or oxidizer utilized with an internal combustion engine to provide for the precise, consistent and repeatable controlled metering of the compressed gaseous fuel and/or oxidizer. The present invention meets these and other needs.

#FIG. 1 is a top plan of the system employing the invention of the application.

#FIG. 2 is a perspective view of the metering pod of FIG. 1.

#FIG. 3 is a lateral cross-sectional view of the body of the metering pod, taken along line 3-3 of FIG. 2.

#As is illustrated in the drawings, the invention is embodied in a metering unit 10, shown in FIG. 1, for a compressed liquid combustible gas and/or fuel oxidizer from a source 12 of compressed liquid combustible gas and/or fuel oxidizer, such as a gas cylinder or tank, carried via a pipe 14, having one or more flexible connections 16, to a gas powered unit 20. Referring to the FIGS. 2-6, the metering unit includes a main body or metering pod 22, with an inlet passage 24 in the end cover 124 of the pod, an outlet passage 26, and as is shown in FIG. 3, a sealed passage 28 in the pod connecting the inlet passage to the outlet passage. Referring again to FIG. 1, the pod may be disposed in a location remote from the gas powered unit, and may have a pipe 30 connecting the outlet passage of the pod to the powered unit. A connector means 32 connects the inlet passage to the source of compressed liquid combustible gas, and a connector means 34 connects the outlet passage to the gas powered unit for providing gas thereto. A shutoff valve 36 can also be included on the hose or pipe, or on the pod in order to allow for the shutoff of the gas.

#Referring to FIGS. 2-6, the metering unit includes an injector metering device 40 disposed in the sealed passage, a pressure sensor 42 for sensing the pressure of the compressed gas in the inlet passage, and as is shown in FIG. 1, means 44 to control the metering of the injector in response to the pressure sensor, such as an electronic processing unit or ECU, to be described below.

#Referring to FIG. 3, the outlet passage has an outlet passage axis 50, and the injector metering device has a jet axis 52, and the jet axis is preferably aligned with the outlet passage axis. The inlet passage also has an inlet passage axis 54, which is preferably substantially perpendicular to the jet axis.