| 摘要 |
The dosimeter measures quantities of water, air and foam-causing agent, by means of a single piston assembly driven by a cam. The piston assembly, which is inside a closed cylinder, (1) consists of an upper piston (2), a lower piston (3) and two rods (10,11). The upper rod is driven by the cam, and the lower rod (11) acts as another piston in an extension (12) of the cylinder. The volume (7) swept by the lower piston (3) is connected to the air supply (22) and the air outlet (24), via non-return valves (21,23). The upper cylinder bore is connected to the water supply (17) and outlet (19), via non-return valves (16, 18). The rod chamber (13) which measures the foaming agent has a similar supply (27), outlet (29) and valves (26,28). The volume (30) in the cylinder above the lower pisto (3) is connected to the atmosphere by a narrow vent (31). |
