Abstract: A mass flowmeter has a U-shaped sensor tube provided on a support base which is supported on a vibration absorbing member, and both ends of the sensor tube are respectively connected to an inlet and an outlet of a manifold. Vibrators are provided at an intermediate part of each straight tube part provided between the inlet and outlet sides of the sensor tube. Pickups are provided on the upstream and downstream sides of each vibrator so as to detect the displacement of the sensor tube. An external vibration is in an opposite direction between the inlet and outlet sides relative to the vibrating direction. Hence, outputs of the pickups located on the upstream sides of the vibrators are added, and outputs of the pickups located on the downstream sides of the vibrators are added. The external vibration is cancelled by obtaining a phase difference of the two added values.

Abstract: A mass flowmeter for measuring a mass flow rate of a fluid passing through a pair of straight tubes in mutually opposing directions by measuring the Coriolis force working on the fluid when the straight tubes are swung to and from each other. The tubes are swung by a vibrator at one end of the tubes and the other end of the tubes is fixed so that the ends of the tubes alternately approach and depart to and from each other. The both ends of the tubes subjected to vibration are connected by a flexible tube.

Abstract: An air fuel ratio control system comprises a first valve provided in a fuel pipe through which a fuel is supplied to a burner, a second valve provided in an air pipe through which air is supplied to the burner, a varying circuit for varying responsive to a preset flow rate of fuel a valve opening degree of each of the first and second valves while maintaining a constant ratio between the valve opening degrees of the first and second valves, so that an air fuel ratio of a flow rate of fuel flowing through the first valve and a flow rate of air flowing through the second valve assumes a value greater than a theoretical air fuel ratio, a first sensor for detecting a flow rate of fuel flowing through the fuel pipe, a second sensor for detecting a flow rate of air flowing through the air pipe, a fuel bypass pipe provided in the fuel pipe for bypassing the first valve, a third valve provided in the fuel bypass pipe, and a control circuit supplied with output signals of the first and second sensors for controlling a

Abstract: This invention relates to a turbine flowmeter comprising an impeller with blades rotatably mounted in a casing and a detection means provided to detect the revolutions of said impeller as a change of electrostatic capacity.