Title:
THERMAL FLOWMETER
Document Type and Number:
Japanese Patent JPH04339218
Kind Code:
A
Abstract:
PURPOSE:To measure a flow rate without generating a disturbance in a fluid even when the flow rate of the fluid is small. CONSTITUTION:A heater 21 is provided on a pipeline through which a fluid flows, an upstream temperature detection element 22a and a downstream temperature detection means 22b are on the upstream and downstream sides of the heater 21 and an arithmetic circuit part 3 is provided to compute a flow rate of the fluid based on outputs of these temperature detection elements 22a and 22b. With the arithmetic circuit section 3, a heating value of the heater 21 is controlled based on the flow rate of the fluid. The heating value of the heater 21 is controlled with the arithmetic circuit section 3 based on the flow rate of the fluid to check overheating of the fluid thereby allowing the prevention of possible bubbles in the fluid. Thus, a drop in flow rate measuring accuracy can be prevented as caused by the generation of the bubbles thereby enabling the obtaining of very good measurement results. This also can prevent thermal reaction or denaturization of the fluid as caused by the overheating.
Inventors:
KAWASAKI KAZUMASA
NAKAMURA AKIRA
KUROMARU TATSURO
NAKAMURA AKIRA
KUROMARU TATSURO
Application Number:
JP465791A
Publication Date:
November 26, 1992
Filing Date:
January 18, 1991
Export Citation:
Assignee:
TOKICO LTD
International Classes:
G01F1/68; G01F1/698; (IPC1-7): G01F1/68
Attorney, Agent or Firm:
Masatake Shiga (2 outside)