Horiba Stec, Co., Ltd.

Yasuhiro Isobe

Yutaka Yoneda

Osamu Horinouchi

Hiroyuki Takeuchi

Yuki Tanaka

Masao Yamaguchi

Masanori Terasaka

Yukimasa Furukawa

Toshihiro Kashima

Koji Imamura

In order to accurately calculate an estimated flow rate by a dynamic constant volume method, a flow rate calculation system including a tank into which fluid flows, an inflow line through which the fluid flows into the tank, and a pressure sensor that detects the pressure inside the tank is adapted to include: a pressure change data storage part that stores pressure change data indicating a temporal change in the pressure detected by the pressure sensor during an inflow period; a flow rate calculation part that calculates the estimated flow rate during the inflow period based on a pressure change rate; and a flow rate correction part that, on the basis of first pressure detected by the pressure sensor after a predetermined time has elapsed after the inflow period and second pressure included in the pressure change data and higher than the first pressure, corrects the estimated flow rate.

Flow rate calculation system, flow rate calculation system program, flow rate calculation method, and flow rate calculation device

The present invention makes it possible to easily obtain a compressibility factor that is a characteristic of a fluid, and thereby dramatically improves the accuracy of flow rate measurement by an ROR system or the like. The invention is adapted to include: a chamber having a constant volume; a flow rate controller connected to the chamber so as to make it possible to introduce or lead a fluid into or out of the chamber at a constant flow rate; and an information processor adapted to calculate a compressibility factor depending on the pressure of the fluid on the basis of time changes in pressure inside the chamber when the fluid is introduced into the chamber at the same flow rate as each other through the flow rate controller under two different pressure conditions inside the chamber.

Fluid characteristics measurement system, program storage medium storing program for fluid characteristics measurement system, and fluid characteristics measurement method

A mass flow controller with high accuracy flow rate output control is disclosed. In the mass flow controller, relation data that indicates a corresponding relation between a flow rate of a reference gas and a CF value of a sample gas is stored, a target flow rate is converted into a reference gas flow rate by the use of a predetermined CF value, a sample gas flow rate is calculated from the converted reference gas flow rate and a CF value corresponding to the reference gas flow rate, the sample gas flow rate is compared with the target flow rate, and the CF value that is used for conversion of the reference gas flow rate or calculation of the sample gas flow rate is updated by the use of the corresponding relation based on the error between the sample gas flow rate and the target flow rate.

Mass flow controller system

An object of this invention is to provide a superior mass flow meter or the like that can flexibly cope with a change of a sample fluid such as a gas kind without requiring a special troublesome labor and that can measure a flow rate with high accuracy. The mass flow meter comprises a sensor section that detects a flow rate of a sample fluid flowing in a flow channel, a setting section that sets a flow rate characteristic function that is intrinsic to each fluid to determine a flow rate based on a flow rate detected value output by the sensor section and an instrumental error correction parameter that is independent from the flow rate characteristic function and common to multiple sample fluids to correct an instrumental error of each mass flow meter, and a flow rate calculating section that calculates a flow rate measurement value of the sample fluid by applying the flow rate characteristic function and the instrumental error correction parameter to the flow rate detected value.

Mass flow meter, mass flow controller, mass flow meter system and mass flow control system containing the mass flow meter and the mass flow controller

In order to improve a measurement accuracy of a mass flow meter, the mass flow meter comprises a flow rate calculating section that obtains an output signal from a sensor section having a thermosensitive resistive element arranged in a flow channel where a sample gas flows and that calculates a flow rate of the sample gas, a pressure measuring section that measures a primary side pressure in the flow channel, and a flow rate correcting section that corrects the measured flow rate obtained by the flow rate calculating section by the use of the primary side pressure obtained by the pressure measuring section and a gas coefficient determined by an isobaric specific heat of the sample gas.

Growing community of inventors

Kyoto, Japan

Yasuhiro Isobe