摘要 |
A fuel supply system for a vehicle uses a multi-piston LPG injunction pump which pumps fluid from a storage tank to an engine. The multi-piston pump uses the vehicle's pneumatic air system, wherein the pressurized air of this system alternatingly drives at least two pistons of the piston pump. Each piston moves through a pumping stroke and a return stroke wherein one piston moves through a pumping stroke, while the opposite piston moves through a return stroke. The pump includes barrier fluid chambers surrounding each of the pistons wherein during a pumping stroke of one piston, a first barrier fluid chamber associated with the one piston decreases in volume as the piston displaces through its pumping stroke. This reduction in volume of the barrier chamber drives the barrier fluid out of the first barrier fluid chamber into a second barrier fluid chamber associated with the second piston. By driving the barrier fluid into this second chamber, this pressurizes the second chamber and effects the displacing movement of the second piston through its return stroke as the barrier fluid chamber increases in volume through the movement of the second piston. |