Abstract: A flow restrictor is provided, comprising a first sheet including a flow passage, and a second sheet stacked on the first sheet. A hole is provided in a center of the second sheet. The flow passage includes a groove cut into a surface of the first sheet that communicates with an expansion zone at a peripheral area of the first sheet. A peripheral edge of the second sheet contacts the first sheet in the expansion zone between an inner diameter and an outer diameter of the expansion zone.

Abstract: A flow rate ratio control device is provided with a main flow path, a plurality of branch flow paths that branch off from a terminus of the main flow path, a plurality of fluid control devices that are provided respectively on each branch flow path, and that are each equipped with a valve and a pressure-based flow rate sensor that is disposed downstream of the valve, and an operation setting unit that establishes settings such that, based on the target flow rate ratio, any one fluid control device from among the plurality of fluid control devices is made to operate in a flow velocity control mode in which the flow velocity of a fluid is controlled upstream of each valve, and the remaining fluid control devices are made to operate in a flow rate control mode in which the flow rate is controlled based on the target flow rates.

Abstract: To provide a flow rate characteristic function identification method, flow rate sensor, and flow rate characteristic function identification program that can set a flow rate characteristic function reflecting not only the type or shape of a fluid resistance but also the effects of states such as an attachment state of the fluid resistance, and calculate a flow rate with higher accuracy. An actual flow rate characteristic function, which is a flow rate characteristic function when an actual fluid resistance is provided in a flow path, is identified on the basis of multiple flow rate characteristic functions including a first reference flow rate characteristic function and a second reference flow rate characteristic function, and predetermined weighting.

Abstract: A flow rate ratio control device is provided with a main flow path, a plurality of branch flow paths that branch off from a terminus of the main flow path, a plurality of fluid control devices that are provided respectively on each branch flow path, and that are each equipped with a valve and a pressure-based flow rate sensor that is disposed downstream of the valve, and an operation setting unit that establishes settings such that, based on the target flow rate ratio, any one fluid control device from among the plurality of fluid control devices is made to operate in a flow velocity control mode in which the flow velocity of a fluid is controlled upstream of each valve, and the remaining fluid control devices are made to operate in a flow rate control mode in which the flow rate is controlled based on the target flow rates.

Abstract: To accurately calibrate fluid control equipment. A flow rate calculation system includes: a container in which gas is enclosed; a weight measurement part on which the container is disposed; a gas line which connects the container and fluid control equipment and in which the gas flows; and an enclosing line for enclosing the gas in the container disposed on the weight measurement part, thereby allowing the gas to flow from the container to the fluid control equipment or from the fluid control equipment to the container in a state that the container is disposed on the weighing measurement part, and calculating a flow rate of the gas flowing to the fluid control equipment based on an output value outputted from the weight measurement part, and the container and the weight measurement part are adapted to be placed in a decompressed decompression chamber.

Abstract: To accurately calibrate fluid control equipment. A flow rate calculation system includes: a container in which gas is enclosed; a weight measurement part on which the container is disposed; a gas line which connects the container and fluid control equipment and in which the gas flows; and an enclosing line for enclosing the gas in the container disposed on the weight measurement part, thereby allowing the gas to flow from the container to the fluid control equipment or from the fluid control equipment to the container in a state that the container is disposed on the weighing measurement part, and calculating a flow rate of the gas flowing to the fluid control equipment based on an output value outputted from the weight measurement part, and the container and the weight measurement part are adapted to be placed in a decompressed decompression chamber.

Abstract: To provide a flow rate characteristic function identification method, flow rate sensor, and flow rate characteristic function identification program that can set a flow rate characteristic function reflecting not only the type or shape of a fluid resistance but also the effects of states such as an attachment state of the fluid resistance, and calculate a flow rate with higher accuracy. An actual flow rate characteristic function, which is a flow rate characteristic function when an actual fluid resistance is provided in a flow path, is identified on the basis of multiple flow rate characteristic functions including a first reference flow rate characteristic function and a second reference flow rate characteristic function, and predetermined weighting.