Abstract: A flowmeter capable of measuring an accurate quantity of flow over a wide range of the quantity of flow. A measurement zone (15) for smaller quantity of flow and a measurement zone (16) for larger quantity of flow are determined inside a flow path (13) of a pipe (10). Regulating strainers (14) for regulating the flow of a gas (20) are disposed inside the measurement zone (15) for smaller quantity of flow by dividing the flow path (13) into a plurality of narrower flow paths (14A). A mean flow velocity of the gas (20) flowing through each of a plurality of narrower flow paths (14A) becomes substantially equal. A part of the gas (20) reaches nozzles (22a, 22b) erected across flow velocity sensors (15a, 15b) for smaller quantity of flow and is accelerated by the operation of these nozzles.

Abstract: A miniaturized, inexpensive flowmeter capable of accurately measuring a flow rate comprises a flow rate detector including a plurality of thermal type flow rate detector elements mounted on a support plate, a power source for applying power to the flow rate detector, and a signal processor for calculating the flow rate from supplied power.

Abstract: A single vibration sensor producing multistage outputs corresponding to various vibrational acceleration values is disclosed. This vibration sensor is the type in which vibrational acceleration causes a movable gravitation element to move, and the movement of the element exerts pressure on a plunger which actuates a switch mechanism and outputs a signal. A feature of this vibration sensor is the switch mechanism includes a number of discrete switch units each having a different operating sensitivity. The switch units have a number of movable members which are displaced by the plunger when the vibrational acceleration causes the movable gravitation element to move, and a number of fixed contacts corresponding to these movable members with which the movable contacts come in contact. The spatial relationship of the fixed contacts with respect to the movable members is a feature which determines the operational sensitivity.

Abstract: A plurality of flow velocity sensors are vertically installed in line at different positions in the same cross section in a gas flow passage in a pipe. Detection signals from the flow velocity sensors are inputted to a mean flow velocity computing unit which calculates a mean value of flow velocity measurements. The mean flow rate calculated at the mean flow velocity computing unit is converted into a flow rate by a flow rate computing unit to be displayed by a display. Regardless of flow velocity distribution in the pipe, which may change due to differences in the pipe shape, flow rates are accurately measured. As a result, flow rates are accurately measured over a wide range.