Abstract: A method is for adjusting a flow measuring device that includes a housing and a flow sensor. The housing includes a bypass flow passage which is formed to take in a part of a mainstream of air. The sensor is disposed in the bypass flow passage and outputs an electrical signal in accordance with a flow rate of air. The bypass flow passage is formed in an asymmetrical shape with respect to the sensor in upstream and downstream directions of the mainstream. A flow from an upstream side toward a downstream side of the mainstream is a forward flow. A flow from the downstream side toward the upstream side of the mainstream is a backward flow. According to the method, an output from the sensor in a backward-flow region is obtained. Furthermore, the output of the sensor in the backward-flow region is adjusted to have a desired output characteristic.

Abstract: A converting map for an area of a backward air-flow is set based on a relationship between an output and a flow-rate, which are obtained in an air flow in which pulsation including the backward air-flow is generated. The backward air-flow has a dynamic property. The converting map of the present disclosure has a conversion characteristic, which is close to a characteristic in the backward air-flow. Accordingly, it is not necessary to correct the converting map by complicated processes and thereby accuracy of measurement for the area of the backward air-flow is increased.

Abstract: A flow measuring device includes a housing, a support, and a flow measurement element. The housing defines a passage therein and includes a passage narrowing part, which reduces a cross-sectional area of the passage, in a predetermined part of the passage. The support has a platy shape and is disposed along a flow direction of fluid flowing in the passage. The flow measurement element is located inside the passage narrowing part and is disposed on a surface of the support. The flow measurement element detects a flow rate of fluid flowing in the passage. The passage narrowing part has an inner wall surface that gradually reduces a width of the passage from a center side to both end sides of the passage in a height direction of the passage, which is perpendicular to a direction of the width of the passage.

Abstract: An air flow measuring device has a throttle portion provided in a first sub-passage, a second sub-passage branched from the first sub-passage at an upstream side of the throttle portion, and a flow amount sensor located in the second sub-passage. The second sub-passage is configured to introduce therein a part of air flowing in the first sub-passage, and an inlet of the second sub-passage is open into the first sub-passage at one side in a first radial direction perpendicular to a flow direction of air flowing in the first sub-passage. Furthermore, the throttle portion is provided to gradually reduce a passage dimension of the first sub-passage in a second radial direction, as toward an outlet of the first sub-passage. Here, the second radial direction is perpendicular to a surface defined by the first radial direction and the flow direction of air in the first sub-passage.

Abstract: An air flow measuring device has a throttle portion provided in a first sub-passage, a second sub-passage branched from the first sub-passage at an upstream side of the throttle portion, and a flow amount sensor located in the second sub-passage. The second sub-passage is configured to introduce therein a part of air flowing in the first sub-passage, and an inlet of the second sub-passage is open into the first sub-passage at one side in a first radial direction perpendicular to a flow direction of air flowing in the first sub-passage. Furthermore, the throttle portion is provided to gradually reduce a passage dimension of the first sub-passage in a second radial direction, as toward an outlet of the first sub-passage. Here, the second radial direction is perpendicular to a surface defined by the first radial direction and the flow direction of air in the first sub-passage.

Abstract: A thermal flow detecting apparatus detects fluid flow in a main flow passage. A bypass passage portion is provided through which some fluid bypasses the main flow passage. A detecting element is provided in the bypass passage portion and arranged at a location eccentrically displaced from the center of a cross section of the bypass passage portion. A throttle portion is provided upstream of the eccentric detecting element in the bypass passage portion for throttling the cross section partially on a side of the detecting element.

Abstract: An air flow measuring device has a throttle portion provided in a first sub-passage, a second sub-passage branched from the first sub-passage at an upstream side of the throttle portion, and a flow amount sensor located in the second sub-passage. The second sub-passage is configured to introduce therein a part of air flowing in the first sub-passage, and an inlet of the second sub-passage is open into the first sub-passage at one side in a first radial direction perpendicular to a flow direction of air flowing in the first sub-passage. Furthermore, the throttle portion is provided to gradually reduce a passage dimension of the first sub-passage in a second radial direction, as toward an outlet of the first sub-passage. Here, the second radial direction is perpendicular to a surface defined by the first radial direction and the flow direction of air in the first sub-passage.

Abstract: An air flow measuring device has a throttle portion provided in a first sub-passage, a second sub-passage branched from the first sub-passage at an upstream side of the throttle portion, and a flow amount sensor located in the second sub-passage. The second sub-passage is configured to introduce therein a part of air flowing in the first sub-passage, and an inlet of the second sub-passage is open into the first sub-passage at one side in a first radial direction perpendicular to a flow direction of air flowing in the first sub-passage. Furthermore, the throttle portion is provided to gradually reduce a passage dimension of the first sub-passage in a second radial direction, as toward an outlet of the first sub-passage. Here, the second radial direction is perpendicular to a surface defined by the first radial direction and the flow direction of air in the first sub-passage.

Abstract: An air flow measuring device includes a first sub-passage portion configured to introduce therein a part of air flowing in an interior of a duct, a passage-area reducing portion provided in the first sub-passage portion to gradually reduce a passage sectional area of the first sub-passage portion as toward an outlet of the first sub-passage portion, and a second sub-passage portion branched from the first sub-passage portion at an upstream side of the passage-area reducing portion in a flow direction of air flowing in the first sub-passage portion. The second sub-passage portion is configured to introduce therein a part of air flowing in the first sub-passage portion. Furthermore, a flow amount sensor is located at an inlet of the second sub-passage portion, at which the second sub-passage portion is branched from the first sub-passage portion, to measure a flow amount of air flowing in the second sub-passage portion.

Abstract: A flow detecting device is provided to a fluid passage through which a main flow of fluid passes. A sensor body has a bypass passage through which a bypass flow passes from the main flow. The bypass passage has a bent portion, which is located midway through the bypass passage, and an outflow passage, which is located downstream of the bent portion. The flow direction of the bypass flow changes at the bent portion toward the outflow passage through the bypass passage. A heating element is arranged in the bypass passage. The heating element generates heat by being supplied with electricity for detecting a flow amount of fluid. The sensor body has a side surface defining an opening through which dynamic pressure caused by counterflow is released to an outside of the outflow passage when fluid causes counterflow in the fluid passage in a direction opposite to a flow direction of the main flow.

Abstract: A substrate includes a first surface portion, which covers a heat receiving portion of a radiation member together with a resinous member. The substrate further includes a second surface portion, which is on the outer periphery of the first surface portion. The substrate makes contact with the resinous member via the second surface portion. The first surface portion and the heat receiving portion have a first contact boundary therebetween. The second surface portion and the resinous member have a second contact boundary that surrounds the first contact boundary. The second contact boundary is sealed using a sealing member. The sealing member is restricted from flowing into a boundary between the first contact boundary and the second contact boundary.

Abstract: A substrate includes a first surface portion, which covers a heat receiving portion of a radiation member together with a resinous member. The substrate further includes a second surface portion, which is on the outer periphery of the first surface portion. The substrate makes contact with the resinous member via the second surface portion. The first surface portion and the heat receiving portion have a first contact boundary therebetween. The second surface portion and the resinous member have a second contact boundary that surrounds the first contact boundary. The second contact boundary is sealed using a sealing member. The sealing member is restricted from flowing into a boundary between the first contact boundary and the second contact boundary.

Abstract: A thermal flow detecting apparatus is provided for detecting fluid flow in a flow passage. The thermal flow detecting apparatus includes a bypass passage portion defining therein a bypass passage through which fluid bypasses the flow passage. The thermal flow detecting apparatus further includes a detecting element that is provided in the bypass passage portion. The detecting element is arranged at a location eccentrically displaced from a center of a cross section of the bypass passage portion. The thermal flow detecting apparatus further includes a throttle portion provided upstream of the detecting element in the bypass passage portion for throttling the cross section partially on a side of the detecting element.

Abstract: A fluid flow detecting apparatus is disclosed for detecting a characteristic of fluid flowing in a fluid passage. The fluid flow detecting apparatus includes a sensor body that defines a bypass passage for flow of a portion the fluid flowing in the fluid passage. The apparatus also includes a sensor provided in the bypass passage for detecting the characteristic of the fluid flowing in the bypass passage and a plurality of plates. The sensor body is provided between the plurality of plates. Each of the plates has a width dimension oriented approximately along the direction of flow of fluid flowing in the fluid passage. The width of the plates is greater than a corresponding width dimension of the sensor body such that the sensor body is inside a region defined between the plates.

Abstract: A measurement body is provided with a sub-outlet arranged between a U-turn portion of a bypass passage and a main outlet. The sub-outlet includes a first sub-outlet positioned on a path of air, which flows on the inside of the bypass passage, and a second sub-outlet positioned on a path of air, which flows on the outside of the bypass passage. The respective sub-outlets open in a sidewall surface of the measurement body along the thickness-wise direction. However, the first sub-outlet and the second sub-outlet are arranged in different positions with respect to the flow direction of measurement air. With this structure, a substantial length of the bypass passage can be adjusted in accordance with positions of the first sub-outlet and the second sub-outlet, so that compensation of intake pulsation is enhanced in accuracy. Thereby, measurement error caused by influences of intake pulsation can be reduced.

Abstract: A sensing unit is constructed of a heater element and a temperature sensing element. The sensing unit is arranged in a region, in which measurement air, which flows into the inflow passage through the bypass inlet, bends at the substantially right-angle and contracts in flow. Alternatively, the sensing unit is arranged in a region immediately after an area, in which the measurement air flowing through the bypass inlet bends at the substantially right-angle. The lengthwise directions of the heater element and the temperature sensing element are respectively arranged to be in parallel with both thickness-wise side faces of the measurement body. Thereby, even when a flow rate of measurement air changes, an influence due to the change can be restricted from being exerted. Therefore, the maximum flow rate can be measured within the lengthwise range of the heater element from a low flow rate to a high flow rate.

Abstract: A fluid flow detecting apparatus is disclosed for detecting a characteristic of fluid flowing in a fluid passage. The fluid flow detecting apparatus includes a sensor body that defines a bypass passage for flow of a portion the fluid flowing in the fluid passage. The apparatus also includes a sensor provided in the bypass passage for detecting the characteristic of the fluid flowing in the bypass passage and a plurality of plates. The sensor body is provided between the plurality of plates. Each of the plates has a width dimension oriented approximately along the direction of flow of fluid flowing in the fluid passage. The width of the plates is greater than a corresponding width dimension of the sensor body such that the sensor body is inside a region defined between the plates.

Abstract: A flow detecting device is provided to a fluid passage through which a main flow of fluid passes. A sensor body has a bypass passage through which a bypass flow passes from the main flow. The bypass passage has a bent portion, which is located midway through the bypass passage, and an outflow passage, which is located downstream of the bent portion. The flow direction of the bypass flow changes at the bent portion toward the outflow passage through the bypass passage. A heating element is arranged in the bypass passage. The heating element generates heat by being supplied with electricity for detecting a flow amount of fluid. The sensor body has a side surface defining an opening through which dynamic pressure caused by counterflow is released to an outside of the outflow passage when fluid causes counterflow in the fluid passage in a direction opposite to a flow direction of the main flow.

Abstract: An intake air flow detecting device is provided to an intake air passage, through which intake air flows into an internal combustion engine. Intake air flow is divided into a main passage and a bypass passage. The detecting device includes a thermal air flowmeter, a bypass flow delay information calculating means, and a response delay compensating means. The thermal air flowmeter includes a detector arranged in the bypass passage for detecting an air flow amount in the intake air passage. The bypass flow delay information calculating means calculates a bypass flow delay information representing delay in variation in a flow amount in the bypass passage with respect to variation in a flow amount in the main passage. The response delay compensating means compensates delay in response of the air flowmeter in accordance with the bypass flow delay information.

Abstract: An airflow meter has a bypass passage disposed in an air passage and a sensing portion disposed in the bypass passage to detect an airflow amount. The bypass passage is provided with a restriction portion to gradually decrease a passage width of the bypass passage in an airflow direction in the bypass passage. The restriction portion includes a first restriction portion and the second restriction portion disposed at an immediately downstream side of a narrowest portion of the first restriction portion. The first restriction portion gradually decreases the passage width in the airflow direction. The second restriction portion increases the passage width than the passage width at the narrowest portion in a stepped manner. The sensing portion is located in a bound in which the restriction portion is disposed.