405 results about "Mass flow sensor" patented technology

The flow sensor comprises a semiconductor device (1) on which a heat source and, symmetrically thereto, two temperature sensors are arranged. The semiconductor device (1) is arranged on an exterior side of a tube section (2), and a liquid, the flow velocity of which has to be measured, is led through the tube section (2). The temperature sensors and the heat source are in thermal contact with the exterior side of the tube section (2). It has been found that such an assembly allows to carry out flow measurements with high accuracy and sensitivity.

A device for measuring fluid flow rates over a wide range of flow rates (<1 nL / min to >10 μL / min) and at pressures at least as great as 2,000 psi. The invention is particularly adapted for use in microfluidic systems. The device operates by producing compositional variations in the fluid, or pulses, that are subsequently detected downstream from the point of creation to derive a flow rate. Each pulse, comprising a small fluid volume, whose composition is different from the mean composition of the fluid, can be created by electrochemical means, such as by electrolysis of a solvent, electrolysis of a dissolved species, or electrodialysis of a dissolved ionic species. Measurements of the conductivity of the fluid can be used to detect the arrival time of the pulses, from which the fluid flow rate can be determined. A pair of spaced apart electrodes can be used to produce the electrochemical pulse. In those instances where it is desired to measure a wide range of fluid flow rates a three electrode configuration in which the electrodes are spaced at unequal distances has been found to be desirable.

An instrument for detecting leaks in a hermetically sealed package. The instrument includes (i) a hollow needle, (ii) a mass flow rate sensor in sealed fluid communication with the lumen defined by the hollow needle, and (iii) a vacuum pump. The vacuum pump is in fluid communication with the lumen defined by the needle for evacuating gas from the hermetically sealed package, and in fluid communication with the mass flow rate sensor for directing mass flow from the evacuated package into operable contact with the mass flow rate sensor so as to permit sensing of any continuing mass flow from the evacuated package. The instrument may further include an oxygen sensor, also in sealed fluid communication with the lumen defined by the hollow needle for analyzing the oxygen concentration of the gas within the hermetically sealed package.

A sensing apparatus for use in a mass flow rate sensor for measuring a fluid flow rate includes a main conduit for containing a fluid flow, and a sensor passageway for tapping a portion of the fluid flow from the main conduit at a first location, and returning the portion of the fluid flow to the conduit at a second location. At least one bypass passageway, which may be provided in the form of a tube, is positioned in the main conduit between the first and second locations, and the bypass passageway is provided with non-negligible entrance effects that are substantially equal to entrance effects of the sensor passageway, so that a bypass ratio of the apparatus remains constant. A mass flow rate sensor of the present disclosure accurately measures any type of gas but only requires calibration in only one reference gas.

The detector for monitoring decrease in air flow rate due to air filter clogging. It is based on combination of three essential components: the air flow sensor, a threshold detector and an indicator. The air flow sensor is built in form of a novel thermo-anemometer which contains a thermistor, a heating element, and a thermal insulator. Temperature of the sensor is maintained above the air temperature by a constant value by means of an electronic servo circuit. The threshold detector is implemented either in a hardware or software. A novel design of a thermo-anemometer (closely related to a hot wire anemometer) automatically compensates for variations in the air temperatures. The thermo-anemometer triggers the threshold circuit when air flow rate drops below a preset level. For reduction of power consumption, the detector may employ two additional sensors: one is for detection of the blower operation and the other is a presence detector to enable the alarm in presence of people to perceive the alarm. The device automatically calibrates itself upon installation of a new or cleaned air filter. The applications include residential and commercial air conditioners, air heaters, internal combustion engines, vacuum cleaners and other systems where air filters are employed.

Provided is a control device for an internal combustion engine, which is provided to allow a throttle opening degree to be controlled in accordance with a target engine intake air flow quantity even during transitional operation. The actual cylinder intake air flow quantity calculating unit (21) calculates a response delay model for an intake system from a volumetric efficiency equivalent value (Kv) calculated from a rotational speed (Ne) of an engine (1) and an intake manifold pressure (Pim), an intake pipe volume (Vs), and a displacement (Vc) of each of cylinders (2), and calculates an actual cylinder intake air amount (Qcr) from an actual engine intake air amount (Qar) obtained from an air flow sensor (4) and the response delay model. The intake air flow quantity controlling unit (24) controls the throttle opening degree (TP) in accordance with the target engine intake air amount (Qat).

A laminated filter is fit in a passage space formed in a body. The laminated filter is made of a mesh plate including a mesh part, a first blocking plate including a blocking part, a second blocking plate including a blocking part, and a third blocking plate including a blocking part which are arbitrarily combined and layered. Accordingly, a three-layered mesh part is placed between a main passage and a sensor passage and a blocking wall is constructed of the three blocking parts.

A system and method is provided for remotely and automatically calibrating a mass-flow sensor in a yield monitor of a combine. The invention uses a wireless communication device installed on a combine and a remote wireless communication device installed on a grain carrier or truck carrier. Once an actual weight is obtained, calibration information is sent to the combine to calibrate the mass-flow sensor.

A blower for combustion air in a wall / floor furnace is provided that includes a blower housing (26), and blower wheel (27), with an air inlet (28) and an air outlet (29), and with a fuel feeder line (1) for fuel, wherein a mass current sensor (13) for determining the air mass current is located on the air inlet (28), which is functionally connected with a data processing device (4) and sends signals to the data processing device for calculation of a ratio of combustion medium to combustion air in dependence on a desired heating capacity.

A flow regulating system for maintaining a stable air flow comprising at least one pump, a mass flow sensor, an ambient temperature sensor, an ambient pressure sensor, a temperature compensation sensor measuring the temperature of said mass flow sensor, and a control system is disclosed, as well as a method for measuring a flow using said flow regulating system, a device for the monitoring of air-borne compounds present in air in both a gas phase and a particle phase, wherein it comprises a sampling device, an enrichment trap 1, a calibration and tuning module, a blank module, said flow regulating system, a chromatography unit, and a detection unit, and a method for the detection of air-born compounds in an air flow by using said monitoring device.