# US 10,371,076 B2 · Intake air flow rate measuring device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,371,076 B2 - Document ID: US10371076B2 - Status: Granted - Kind: B2 - Application number: 15/647,298 - Filed: 2017-07-12 - Published: 2018-01-25 - Granted: 2019-08-06 - Earliest claimed: 2016-07-20 - Assignees: Denso Corporation - Applicants: Denso Corporation - Inventors: Keisuke Itakura - Web page: https://patentgrep.com/patent/US10371076B2 ## CPC - F02D 41/18: by measuring intake air flow - G01F 1/6842: {with means for influencing the fluid flow} - G01F 5/00: Measuring a proportion of the volume flow - G01F 15/12: Cleaning arrangements; Filters - F02D 2041/281: {between sensors and control unit} - F02D 2041/286: {comprising means for signal processing} - F02D 2200/0414: Air temperature - F02D 2200/0418: Air humidity - F02D 2400/18: Packaging of the electronic circuit in a casing - F02D 2400/22: Connectors or cables specially adapted for engine management applications - F02D: CONTROLLING COMBUSTION ENGINES (vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed B60K31/00; conjoint control of vehicle sub-units of different type or different function, road vehicle drive control systems for purposes other than the control of a single sub-unit B60W) - G01F: MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME ## Abstract The present disclosure provides an intake air flow rate measuring device. The intake air flow rate measuring device includes a flange, a casing, a flow rate sensor, a humidity sensing element, an element terminal, and a humidity terminal. The humidity terminal is spaced away from the element terminal. A portion of the casing between the element terminal and the humidity terminal is defined as a suppressing portion, and a cross-section of the suppressing portion is defined as a suppressing portion cross-section. An end portion of the casing close to the flange is defined as a base portion, and a cross-section of the base portion is defined as a base portion cross-section. The suppressing portion cross-section is set to be smaller than the base portion cross-section. ## Claims ### Claim 1 An intake air flow rate measuring device that is inserted into an attachment hole of an intake air duct introducing an intake air into an engine, the intake air flow rate measuring device measuring a flow rate of the intake air flowing through the intake air duct, the intake air flow rate measuring device comprising: a flange that is disposed outside of the intake air duct to cover the attachment hole; a casing that extends in both the attachment hole and the intake air duct; a flow rate sensor that is disposed in the casing to measure a flow rate of the intake air flowing through the intake air duct; a humidity sensing element that is disposed in the casing to measure a humidity of the intake air flowing through the intake air duct; an element terminal that is positioned only inside the intake air duct and is electrically connected to the humidity sensing element; and a humidity terminal that passes through the flange, wherein the humidity terminal is positioned spaced away from the element terminal, an electric connector is disposed between the humidity terminal and the element terminal to electrically connect the humidity terminal to the element terminal, heat is less likely to transfer through the electric connector as compared to the humidity terminal and the element terminal, a portion of the casing between the element terminal and the humidity terminal is defined as a suppressing portion, and a cross-section of the suppressing portion is defined as a suppressing portion cross-section, and an end portion of the casing close to the flange is defined as a base portion, and a cross-section of the base portion is defined as a base portion cross-section, wherein the suppressing portion cross-section is set to be smaller than the base portion cross-section. ### Claim 2 (depends on 1) The intake air flow rate measuring device according to claim 1, wherein the casing includes a main body housing the flow rate sensor, and a humidity sensor including the humidity sensing element, the main body and the humidity sensor are separately supported by the flange, the humidity sensor includes a circuit substrate, as the element terminal, on which the humidity sensing element is disposed, and a molding resin that covers the humidity sensing element and the circuit substrate, and the suppressing portion is a portion of the molding resin between the circuit substrate and the humidity terminal. ### Claim 3 (depends on 1) The intake air flow rate measuring device according to claim 1, wherein the casing includes a main body housing both the flow rate sensor and the humidity sensing element, and the suppressing portion is a portion of the main body of the casing. ### Claim 4 (depends on 1) The intake air flow rate measuring device according to claim 1, wherein the electric connector has thermal resistance greater than that of the humidity terminal. ### Claim 5 (depends on 4) The intake air flow rate measuring device according to claim 4, wherein the electric connector is formed of an electrically conductive wiring subject to wire bonding. ### Claim 6 (depends on 4) The intake air flow rate measuring device according to claim 4, wherein the electric connector is a ceramic substrate on which a conductive metallic pattern is printed. ### Claim 7 (depends on 4) The intake air flow rate measuring device according to claim 4, wherein the electric connector is a flexible substrate on which a conductive metallic pattern is printed. ### Claim 8 (depends on 1) The intake air flow rate measuring device according to claim 1, wherein the casing includes a flow rate terminal that is disposed, separately with the humidity terminal, inside the casing and is electrically connected to the flow sensor, and the humidity terminal has thermal conductivity less than that of the flow rate terminal. ### Claim 9 (depends on 1) The intake air flow rate measuring device according to claim 1, wherein the humidity terminal has a shape that is tapered toward the element terminal. ### Claim 10 (depends on 1) The intake air flow rate measuring device according to claim 1, wherein the suppressing portion is located to be directly exposed to the intake air flowing through the intake air duct. ### Claim 11 (depends on 1) The intake air flow rate measuring device according to claim 1, wherein the electric connector is disposed in a housing space defined in the casing.