Abstract: An air intake measuring apparatus for an internal combustion engine comprises a bypass passageway formed in a throttle body by bypassing a venturi section in a suction passage, and a thermal probe arranged in the bypass passageway for determining the air intake by measuring the flow velocity of an air current flowing through the bypass passageway. A venturi member for forming in the throttle body the venturi section and the bypass passageway is force fitted in the throttle body to provide a unitary structure. The bypass passageway has an inlet port of a static pressure introducing type formed on the side of the suction passage and outlet ports formed in the venturi section close to the inlet port, while the thermal probe is located in the bypass passageway in a segment thereof of a minimum cross-sectional area.

Abstract: A low pressure drop hot film/swirl air flowmeter (10) for an automotive engine is disclosed. The flowmeter includes a main air flow passage (18), a relatively small secondary passage such as a venturi (20) disposed within the passage for receiving a portion of the air flow, a tertiary passage (50) which draws an air sample from the main air flow passage and discharges it into the venturi throat (44), a constant temperature thermal anemometer (48) positioned to sense the sample air flowing in the tertiary passage, and a set of swirl vanes (22) operative to impart a swirl to the remainder of the air in the main passage, thereby creating a reduced pressure at the venturi outlet for forced aspiration therethrough without appreciably increasing the pressure drop across the flowmeter. The anemometer includes a bridge circuit (114), one leg of which comprises a resistive sensor (82) within the tertiary passage.

Abstract: An air flow rate measuring device has a by-pass passage branched from a main air passage leading to an engine, and heat wires provided in the by-pass passage. The inlet of the by-pass passage is positioned at the upper end of a venturi tube disposed in the main air passage, shaped annularly, and opened to the main air passage so that the air at the inlet can be subjected to the dynamic pressure of the main air stream. The outlet of the by-pass passage also is annularly formed and opened normally to the main air stream in the main air passage. The flow rate of air sucked into the engine is measured by the heat wires subjected to air flow taken in the by-pass passage.

Abstract: A fluid conduit with a rectangular cross-section is divided into two parallel conduits. A vortex generating rod is disposed perpendicularly to the flow direction in one of the conduits. An ultrasonic wave is directed perpendicularly across the conduit to detect the Karman vortex streets. A sound absorbing material is located along the portion of the conduit wall where the ultrasonic waves exist for preventing the formation of standing waves.

Abstract: An apparatus for measuring and/or sampling the milk-yield of a cow during milking is described. The apparatus comprises a housing with a milk inlet and a milk outlet and a rotation-symmetric distributing means mounted in a drain chamber. A buffer chamber is formed in the housing above the drain chamber, in which buffer chamber the incoming milk stream is received. The buffer chamber is connected to the drain chamber by a cylindrical bore formed in its bottom wall, said bore being coaxial with the distributing means. Means are provided adapted to permit a milk flow to the distributing means through the cylindrical bore only when a predetermined milk quantity is received in the buffer chamber, said means interrupting said milk flow at a second smaller milk quantity in the buffer chamber. The distributing means provides a radial flowing milk film a portion of which is conducted to a measuring means through a receiving chamber.

Abstract: An intake barrel connected to an intake pipe of an internal combustion engine is provided therein with a venturi member. Openings are formed in the wall of the intake barrel at the upstream and downstream sides of the venturi member. A bypass passage forming member provided with a groove of a length greater than the distance between said openings is fixed to the outside of the intake barrel. A bypass passage is formed by these openings and the groove. A spacer is interposed between the intake barrel and the bypass passage forming member. The cross-sectional area of the bypass passage can be varied by varying the thickness of the spacer.

Abstract: A low pressure drop air flowmeter (10) for an automobile engine is disclosed. The meter contains a main air flow passage (24), a relatively small venturi (20) to receive a portion of the air flow, pressure ports (98a and 120) for sensing stagnation and static pressure and a set of swirl vanes (22) disposed adjacent the outlet of the venturi and operative to impart a swirl to the remainder of the air in the main passage, thereby creating a reduced pressure at the venturi outlet for amplifying the pressure difference between the stagnation and static pressure without appreciably increasing the pressure drop across the flowmeter. A tertiary passage (28) provides a path of fluid communication between points upstream and downstream of the swirl vanes. This passage includes a flow restricting throat (29) which is manually calibrated during or after assembly. Air exiting the tertiary passage impinges upon the swirl to modulate the vortex velocities.

Abstract: A low pressure drop air flowmeter for an automobile engine is disclosed. The meter contains a main air flow passage, a relatively small venturi to receive a portion of the air flow, pressure ports for sensing stagnation and static pressure and a set of swirl vanes disposed adjacent the outlet of the venturi and operative to impart a swirl to the remainder of the air in the main passage, thereby creating a reduced pressure at the venturi outlet for amplifying the pressure difference between the stagnation and static pressure without appreciably increasing the pressure drop across the flowmeter. A tertiary passage provides a path of fluid communication between points upstream and downstream of the swirl vanes. This passage can be selectively opened or restricted by a valve which, in the preferred embodiment of the invention, opens the tertiary passage with increasing overall flow rate.

Abstract: A method of testing a fluid is disclosed which comprises passing a main flow of a fluid through a conduit; inserting into said conduit a probe having an inlet opening which faces downstream of the conduit, or is disposed in a chamber communicating with the conduit, the inlet opening communicating with an outlet opening which is disposed in an end surface of the probe; the said main flow, in passing through the conduit, causing a sampling flow of the fluid to be drawn from the conduit, and to be passed through the probe from the inlet opening to the outlet opening, and so back to the conduit; and testing said sampling flow.

Abstract: A by-pass flowmeter of coaxial design comprises a transparent outer tube and a rotameter coaxially disposed within the outer tube and laterally spaced therefrom to define an annular by-pass chamber. An inlet is at least partially disposed within one end of the outer tube in fluid communication with both the rotameter inlet and an adjacent portion of the by-pass chamber while an outlet is at least partially disposed within the other end of the outer tube in fluid communication with both the rotameter outlet and an adjacent end portion of the by-pass chamber. As the by-pass flowmeter is of coaxial design, greater accuracy is obtainable than with by-pass flowmeters of non-coaxial design.

Abstract: A mass flow sensor system for measuring the flow rate of a fluid in a sensing tube at diverse angular attitudes. Output signal distortion is minimized by neutralizing the effects of convection forces. The sensing tube is formed as a by-pass coupled to a fluid conduit and includes a loop in the shape of a single-turn helix. Circulation of the fluid through the loop cancels gravity-induced convection forces caused by temperature gradients and significantly reduces sensitivity to attitude change. Heating and temperature-sensing resistor coils are wound around the outer surface of the looped portion of the tube. The heater increases the tube temperature above that of the entering fluid, and the temperature difference between the temperature sensors, corresponding to rate of mass flow, is detected as a voltage output signal generated in an associated bridge circuit.

Abstract: A mass flow sensor system for measuring the flow rate of a fluid in a sensing tube at diverse angular attitudes. Output signal distortion is minimized by neutralizing the effects of convection forces. The sensing tube is formed as a by-pass coupled to a fluid conduit and includes a loop in the shape of a single-turn helix. Circulation of the fluid through the loop cancels gravity-induced convection forces caused by temperature gradients and significantly reduces sensitivity to attitude change. A center-tapped temperature-sensitive resistor coil is wound around the outer surface of the loop. The coil is heated, and the temperature differential between the ends of the coil, corresponding to rate of mass flow, is detected as a voltage output signal generated in an associated bridge circuit.

Abstract: Apparatus for measuring the flow of fluid through a main supply line having a restrictive element therein to develop a pressure drop. A shunt fluid flow path bypasses this element. The shunt path includes a conduit having a first electrically heated portion and an unheated portion, each portion respectively having a temperature sensing device associated therewith. Means are provided for varying the voltage supplied to an electrical heater for the first conduit portion to maintain a constant temperature difference between the temperature sensing devices, the amount of voltage supplied being a function of the characteristics of fluid flow through the main supply line.

Abstract: A rotary fluid flowmeter device comprising a casing enclosing a chamber bounded partly by a fluid-tight but magnetically permeable partition, said chamber having an inlet and an outlet for the fluid of which the flow is to be metered, and a rotor having radially-directed, axially-extending blades being borne for rotation within the chamber, wherein in operation fluid entering the chamber through the inlet is directed towards and impinges upon the rotor blades to cause rotation of the rotor, and wherein the casing houses an electronic sensing circuit on the far side of the partition from said chamber, the circuit being adapted to produce an electronic pulse train the rate of which represents the rate of rotation of the rotor.