Liquid flow meter calibration device

摘要

PROBLEM TO BE SOLVED: To provide a liquid flowmeter calibration apparatus which enables high precision calibration in a range of an infinitesimal flow rate.SOLUTION: A liquid flowmeter calibration apparatus comprises: a weighing vessel for capturing a test liquid; a weighing scale for measuring the weight of the weighing vessel; a capturing flow channel for routing the test liquid to the weighing vessel; an injection nozzle for injecting the test liquid into the weighing vessel; a bypass flow channel for routing the test liquid to a draining tank when the test liquid is not captured into the weighing vessel; a flow channel switching mechanism for switching the routing destination of the test liquid between the capturing flow channel and the bypass flow channel; a weighing vessel chamber box surrounding the weighing vessel; a suction nozzle for draining the test liquid from the weighing vessel; and means for moving the injection nozzle and the suction nozzle between the weighing vessel and the draining tank. The flow channel switching mechanism is constituted of two on-off valves or one three-way valve and further the test liquid is routed to the weighing vessel through the capturing flow channel and the injection nozzle, such that the flow of the test liquid is switched in closed flow channels to allow the test liquid to reach the weighing vessel without being exposed to the air.SELECTED DRAWING: Figure 8