Abstract: The physical quantity measurement device includes a passage flow channel, a branch flow channel, and a physical quantity detection unit. A direction along which a pair of opposing surfaces facing each other are arranged is defined as a width direction, and a direction orthogonal both to the width direction and an inflow direction of fluid through an inflow port is defined as a height direction. An inner peripheral surface of the passage flow channel includes a height narrowing surface that narrows the passage flow channel so that a height dimension of the passage flow channel along the height direction is gradually reduced toward the outflow port while reserving a parallel region extending linearly between the inflow port and the outflow port parallel to the inflow direction. The height narrowing surface is not exposed through the inflow port in the inflow direction.

Abstract: A physical quantity measurement device that measures a physical quantity of a fluid has an inflow port and an outflow port, and includes a passage flow channel, a branch flow channel, and a physical quantity detector. An inner peripheral surface of the passage flow channel extends over a pair of facing surfaces, which face each other across the flow passage boundary portion and the inflow port on an upstream side of the flow channel boundary portion. The inner peripheral surface further includes an inflow step surface which forms a step facing the inflow port side.

Abstract: A measurement control device measures an air flow rate using an output value of a sensing portion that outputs a signal according to the air flow rate, and outputs the measurement result of the air flow rate to a predetermined external device. The measurement control device includes: a pulsation state calculator that calculates a pulsation state, which is a state of pulsation generated in the air flow rate, by using the output value of the sensing portion instead of acquiring an output value from an external device; and a flow rate correcting unit that corrects the air flow rate using the pulsation state calculated by the pulsation state calculator.

Abstract: A physical quantity sensing device is installed to a circuit board and is configured to output a signal, which corresponds to a physical quantity of air flowing through a physical quantity measurement passage. A physical quantity measurement passage inlet, which is communicated with the physical quantity measurement passage, includes a first inner surface and a second inner surface. A second distance, which is measured from the physical quantity sensing device to the second inner surface in a plate thickness direction of the circuit board, is larger than a first distance, which is measured from the circuit board to the first inner surface in the plate thickness direction of the circuit board.

Abstract: A gas flow rate measurement device includes a flow rate sensor that outputs a voltage that includes variations due to differences in an external environment and variations due to individual differences, a correction coefficient storage unit that stores a correction coefficient for correcting the output voltage of the flow rate sensor based on a corresponding relationship between the output voltage of the flow rate sensor and the flow rate of the gas, and a correction calculation unit that corrects the output voltage of the flow rate sensor by using the correction coefficient. The correction coefficient is a coefficient for directly converting the output voltage of the flow rate sensor into an ideal voltage value that does not include the variations due to the differences in the external environment and does not include the variations due to the individual differences in the flow rate sensor.

Abstract: In a measurement control device that measures an airflow, an amplitude calculator calculates, by use of an output value of a sensor, a pulsation amplitude that is a difference between a pulsation maximum and an average airflow or a difference between the pulsation maximum and a pulsation minimum. The pulsation maximum is a maximum value of pulsation generated in the airflow, the average airflow is an average value of the pulsation, and the pulsation minimum is a minimum value of the pulsation. A correction parameter acquirer acquires a correction parameter corresponding to the calculated pulsation amplitude by use of a correction characteristic. An airflow corrector corrects the airflow by use of the acquired correction parameter.

Abstract: A physical quantity measurement device includes a passage flow channel, a branch flow channel, and a physical quantity detection unit. An inflow region extending from the inflow port and a lateral region laterally arranged to the inflow region are included in at least one of the passage flow channel and the branch flow channel. The physical quantity detection unit is disposed in the lateral region. A guiding surface that guides away from the lateral region in the lateral direction foreign matter is included in at least one of an inner peripheral surface of the passage flow channel and an inner peripheral surface of the branch flow channel at a position upstream of the lateral region.

Abstract: A physical quantity measurement device includes a housing forming a measurement flow path, a physical quantity sensor that detects a physical quantity of fluid in the measurement flow path, and a sensor support that supports the physical quantity sensor. The sensor support includes a support front surface on which the physical quantity sensor is disposed, and a support back surface behind the support front surface. The housing includes a floor surface facing a support end of the sensor support, a front wall surface facing the support front surface, and a back wall surface opposite to the front wall surface across the floor surface and facing the support back surface. A front distance between the physical quantity sensor and the front wall surface in a front-back direction is larger than a floor distance between the floor surface and the support end in a height direction orthogonal to the front-back direction.

Abstract: A physical quantity measurement device includes a housing forming a measurement flow path through which the fluid flows and a container space that houses a part of a detection unit. An inner surface of the housing includes a housing intersecting surface that intersects an arrangement direction in which the measurement flow path and the container space are arranged, a housing flow path surface extending from the housing intersecting surface toward the measurement flow path, and a housing container surface extending from the housing intersecting surface toward the container space. The housing includes a housing partition that protrudes from the inner surface toward the detection unit and contacts the detection unit between the housing and the detection unit such that the housing partition separates the measurement flow path and the container space from each other.

Abstract: A physical quantity measurement device includes a housing forming a measurement flow path in which a sensor support supports a physical quantity sensor. The measurement flow path includes a sensor path in which the physical quantity sensor is disposed, an upstream curved path between the sensor path and an inlet, and a downstream curved path between the sensor path and an outlet. The housing includes a measurement narrowed portion that gradually narrows the measurement flow path in a direction from the inlet toward the physical quantity sensor. An upstream end of the sensor support is provided upstream of the measurement narrowed portion in an arrangement cross section along an imaginary straight line passing through the physical quantity sensor and extending in an arrangement direction in which the upstream curved path and the downstream curved path are arranged.

Abstract: A physical quantity measurement device includes a housing forming a through flow path, and a measurement flow path branching from the through flow path. A physical quantity sensor is provided in the measurement flow path. An inner surface of the housing includes an inlet ceiling surface and an inlet floor surface which face each other and define an inlet through path that is between and connects an inlet of the through flow path and an inlet of the measurement flow path, The inlet ceiling surface includes a ceiling inclined surface that extends from the inlet of the through flow path and is inclined with respect to the inlet floor surface. A distance between the ceiling inclined surface and the inlet floor surface gradually decreases in a direction from the inlet of the through flow path toward an outlet of the through flow path.

Abstract: A physical quantity measurement device includes a housing forming a measurement flow path including a measurement inlet and a measurement outlet. The measurement flow path includes a sensor path in which a physical quantity sensor is disposed, an upstream curved path curved to extend from the sensor path toward the measurement inlet, and a downstream curved path curved to extend from the sensor path toward the measurement outlet. An inner surface of the housing includes an upstream outer curved surface that defines an outer outline of a curved part of the upstream curved path, and a downstream outer curved surface that defines an outer outline of a curve part of the downstream curved path. A degree of recess of the downstream outer curved surface is larger than a degree of recess of the upstream outer curved surface.

Abstract: An intake air amount measuring device includes a by-pass-type air flowmeter and a processor that calculates an intake air amount of an engine based on the measurement result of the air flowmeter. When calculating the intake air amount, the processor performs lag or lead compensation for a response delay of a change in an intake flow rate in the bypass passage in relation to a change in an intake flow rate in the main passage based on loss coefficients of the main passage and the bypass passage. The processor causes values of the loss coefficients of the main passage and the bypass passage, which are used in the compensation, to be different between a forward flow state, in which the intake air flows through the main passage in a forward direction, and a back-flow state, in which the intake air flows through the main passage in a reverse direction.

Abstract: An air flow rate measurement device includes a flow rate detection unit, a detected flow rate response compensation unit, a pulsation amplitude calculation unit, a correction value calculation unit, and an error correction unit. The flow rate detection unit detects a detected flow rate. The detected flow rate response compensation unit advances a response time of the detected flow rate and calculating a compensation flow rate which is an output obtained by compensating for a response delay of the detected flow rate. The pulsation amplitude calculation unit calculates a pulsation amplitude correlated with a pulsation amplitude in the detected flow rate. The correction value calculation unit calculates a pulsation correction value which is a value for correcting the compensation flow rate based on the pulsation amplitude. The error correction unit corrects the compensation flow rate based on the pulsation correction value.

Abstract: A physical quantity measurement device includes a measurement channel through which the fluid flows to be measured, a physical quantity detector that detects a physical quantity of a fluid in the measurement channel, a housing forming the measurement channel, and a measurement outlet provided in the housing as a downstream end of the measurement channel. An outer peripheral surface of the housing includes an outer peripheral flat surface that extends in an arrangement direction along which an upstream end and a downstream end of the housing are arranged, and an outer peripheral inclined surface inclined with respect to the outer peripheral flat surface and provided between the upstream end and the outer peripheral flat surface in the arrangement direction. The measurement outlet is positioned upstream of the downstream end of the housing.

Abstract: An air flow meter includes a processing unit measuring an air flow rate based on an output signal of a sensing unit placed in environment where air flows and outputting the air flow rate to an ECU. The processing unit includes an intake air flow rate computation unit acquiring an air flow rate based on the output signal, and an argument acquisition unit and a pulsation correction value computation unit acquiring pulsation correction information for correcting a pulsation error based on the acquired air flow rate. The processing unit also includes an air flow meter output unit outputting pulsation correction information in addition to the air flow rate to the ECU.

Abstract: A physical quantity measurement device measures a physical quantity of a fluid. A detection unit has a physical quantity detector that detects a physical quantity of the fluid in a measurement flow channel. A housing accommodates at least a part of the detection unit and forms the measurement flow channel. The housing includes a housing attachment that is attached to a predetermined attaching target, and a position holder holding a position of the detection unit by contacting the detection unit. The housing includes an inward part positioned inward of the attaching target and an outward part positioned outward of the attaching target. The position holder is provided inward of the housing attachment in an alignment direction along which the inward part and the outward part are aligned.

Abstract: An air flow meter includes an inward part that is positioned inward of an intake pipe and an outward part that is positioned not inward but outward of the intake pipe. The air flow meter further includes a first detector provided in the inward part, and a second detector provided at a position closer to the outward part than the first detector.

Abstract: The physical quantity measurement device includes a passage flow channel, a branch flow channel, and a physical quantity detection unit. A direction along which a pair of opposing surfaces facing each other are arranged is defined as a width direction, and a direction orthogonal both to the width direction and an inflow direction of fluid through an inflow port is defined as a height direction. An inner peripheral surface of the passage flow channel includes a height narrowing surface that narrows the passage flow channel so that a height dimension of the passage flow channel along the height direction is gradually reduced toward the outflow port while reserving a parallel region extending linearly between the inflow port and the outflow port parallel to the inflow direction. The height narrowing surface is not exposed through the inflow port in the inflow direction.

Abstract: A physical quantity measurement device includes a passage flow channel, a branch flow channel, and a physical quantity detection unit. An inflow region extending from the inflow port and a lateral region laterally arranged to the inflow region are included in at least one of the passage flow channel and the branch flow channel. The physical quantity detection unit is disposed in the lateral region. A guiding surface that guides away from the lateral region in the lateral direction foreign matter is included in at least one of an inner peripheral surface of the passage flow channel and an inner peripheral surface of the branch flow channel at a position upstream of the lateral region.