FLOW RATIO CONTROL DEVICE, PROGRAM FOR FLOW RATIO CONTROL DEVICE, AND FLOW RATIO CONTROL METHOD

To provide a flow ratio control device with which it is possible, not only to achieve a target flow ratio, but also to control the time required to achieve the target flow ratio, provided is a flow ratio control device, comprising: a main flow path; a plurality of branch flow paths which branch from a terminal end of the main flow path; a plurality of fluid control devices which are disposed uponeach of the branch flow paths, and each of which comprises a valve and a pressure-type flow sensor which is positioned to the downstream side of the valve; and an operation setting unit which, on thebasis of a target flow ratio, sets one of the fluid control devices from among the plurality of fluid control devices to operate in a flow speed control mode for controlling a flow speed of a fluid tothe upstream side of each of the valves, and sets the other fluid control devices to operate in a flow rate control mode for controlling the flow rate on the basis of a target flow rate. 为了提供一种不仅能达成目标流量比率而且能对到达成该目标流量比率为止所耗费的时间