| 摘要 |
A manually operated refrigerant recovery pump includes a piston/cylinder (34) wherein the piston defines opposing fluid chambers (30, 32) in the cylinder. A handle (28) is attached via a connecting rod to the piston. First (17) and second (19) one-way check valves are provided at the pump inlet (20) and outlet (22) to ensure that fluid flows in only one direction through the pump. A pressure relief valve (36) is in fluid communication with the fluid chamber (30) opposite the pump chamber (32) and is continuously manually adjustable between an open and closed position. The pressure relief valve is closed upon initial pressurization of the pump to dampen sudden upward movement of the pump and open during pumping to facilitate manual pumping. |
