Compressed gas fueling system

A fueling system for a vehicle equipped with an engine fueled by compressed gas and gas storage means for providing the compressed gas to the engine and for storing the gas under pressure, comprising:

• a two-to-four stage compressor on board the vehicle for receiving gas at a first pressure through an inlet and outputting the gas through an outlet at a second pressure higher than the first pressure;
• an electric motor for providing power to the compressor, including electric connector means for connecting the motor to ac line voltage located outside the vehicle;
• an inlet line for removably connecting the inlet to a source of low-pressure gas outside the vehicle for providing gas at the first pressure, wherein the inlet line includes a quick-disconnect fitting for connecting to a mating quick-disconnect fitting at an outlet of the source of low-pressure gas, a shut-off valve, an accumulator and first pressure switch means for permitting operation of the compressor when the pressure in the accumulator is at least about a minimum pressure and for prohibiting operation of the compressor when the pressure in the accumulator is less than about the minimum pressure;
• and
• an outlet line for providing a high-pressure connection between the outlet and the gas storage means, including a check valve restricting a flow of gas from the gas storage means to the outlet, and second pressure switch means responsive to the second pressure in the outlet line for turning the compressor off when the second pressure reaches a predetermined maximum pressure.

A method of fueling a vehicle equipped with an engine fueled by compressed gas and fuel storage means for storing the gas under pressure and for providing the gas to the engine, comprising the steps of:

• providing, on board the vehicle, a fueling system that includes a gas compressor, an electric motor for powering the compressor, electric connector means for removably connecting the motor to a source of electric power off the vehicle, low-pressure connector means for removably connecting an inlet of the compressor to a source of low-pressure gas outside the vehicle and a high-pressure gas line between an outlet of the compressor and the fuel storage means;
• connecting the inlet of the compressor to the source of low-pressure gas with the low-pressure connector means;
• providing gas at a first pressure to the inlet of the compressor;
• connecting the motor to the source of electric power with the electric connector means;
• providing electric power to the motor;
• powering the compressor with the motor;
• compressing the gas entering the inlet with the compressor;
• and
• outputting the gas through the high-pressure gas line at a second pressure greater than the first pressure, whereby the fuel storage means is filled with gas at the second pressure;
• wherein the step of providing gas at the first pressure to the inlet includes the step of accumulating gas in an accumulator upstream from the inlet.