Patent application number | Description | Published |
20080229818 | THERMAL FLOWMETER - To reduce power consumption by a thermal flowmeter while good flow-rate detection sensitivity is maintained, it is only necessary to reduce power consumption by a heat resistor under predetermined conditions. Specifically, provided that a width Wh of the heat resistor is between 100 micrometers and 400 micrometers inclusive (100≦Wh≦400), it is only necessary that a relationship among the length Lh of the heat resistor, a temperature increase ΔTh for the heat resistor, and a maximum permissible power Phmax to be supplied to the heat resistor be set so as to satisfy a formula 1.4≦ΔTh·Lh/Phmax≦2.8 in order to maintain good flow-rate detection sensitivity. Accordingly, the length of the heat resistor and the temperature increase in the heat resistor are set so that the maximum power consumption can be reduced within a range in which the formula is satisfied. | 09-25-2008 |
20080282791 | Thermal Flowmeter - A simply configured thermal flowmeter can provide high measurement accuracy over a long period of time by suppressing the characteristics degradation due to adhering contaminants. On the surface of a diaphragm part, a heater resistor is formed. Temperature difference sensors through are disposed on the two sides of the heater resistor (upstream and downstream sides in the flow direction of an air stream). The temperature difference sensors are disposed upstream of the heater resistor while the temperature difference sensors are disposed downstream of the heater resistor. Outside the temperature difference sensors, heating temperature sensors are formed. Control is performed so that the temperature of the heating temperature sensors is set higher than the air stream temperature by a certain degree. Therefore, even if contaminants adhere to the sensor device, the temperature of the heating temperature sensors is held constant. Since the temperature difference sensors to detect the flow rate is located between the heating temperature sensors, the temperature change due to the contamination is small. This suppresses the characteristics degradation, making it possible to provide high measurement accuracy over a long period of time. | 11-20-2008 |
20080295575 | GAS FLOWMETER AND ENGINE CONTROL SYSTEM - In a gas flowmeter in which a rod and a sensor element are formed as a single body, for preventing heat of the sensor element from flowing into a sensor probe through a substrate (rod) so as to suppress considerable power consumption, and for obtaining a necessary response speed with respect to a flow rate of gas to be measured or a change in temperature, the gas column (rod) is made of an insulating material on a center axis of the sensing probe and is formed with a conductor pattern on its surface, and the sensing probe connects the sensor element disposed in a pipe through which the gas to be measured flows and a harness terminal through the conductor on the surface of the rod, so as to measure a gas flow rate by using the sensing prove. | 12-04-2008 |
20090000372 | Thermal Flow Measurement Device - Conventional thermal flow measurement devices lack consideration for automobiles in severe environments. A detection element of the thermal flow measurement device according to the present invention is structured by the provision of a planar substrate made of a material having good thermal conductivity, such as silicon or ceramic, with a thin-walled portion (diaphragm). On the surface of the thin-walled portion, the detection element comprises a heat element as a heater heated to a temperature being different to a predetermined extent from the temperature of the air flow to be measured, temperature-detecting resistors as temperature-detecting means on both sides of the heat element, wiring portions formed of electrical conductors that draw signal lines from the heat element and the temperature-detecting resistors and that have a melting point of 2000° C. or higher, and pads. | 01-01-2009 |
20090126477 | Air Flow Measuring Instrument - An air flow measuring instrument, comprising: an auxiliary passage | 05-21-2009 |
20090241660 | THERMAL TYPE FLOWMETER - In the thermal type flowmeter for measuring the flow rate by a measuring element with an exothermic resistor and a temperature measuring resistor being shaped in the side of the surface of a substrate, a facing wall facing the surface of the measuring element is arranged, cantilever plate parts protruding from the facing wall toward the measuring element side are arranged, a gap is provided between the tip of the cantilever plate parts and the measuring element, and the cantilever plate parts are extended from the upper stream to the down stream of the measuring element. | 10-01-2009 |
20100077851 | Air Flow Meter - In a structure in which peripheral part of a diaphragm section of an electrical insulating film is covered with a protective film made of an organic material, the resistor wire on the diaphragm section crosses the peripheral part of the diaphragm section. At a place where a narrow wire of a resistance temperature detector and the like crosses the peripheral part of the diaphragm section, the protective film is thinner than the other part, and the dust impact resistance is reduced. At a place where a heating resistor wire connected to a heating resistor body or resistance temperature detector wires connected to resistance temperature detector bodies cross a periphery of the diaphragm section, a film component protruding from an electrical insulating film is arranged side by side with the heating resistor wire or the resistance temperature detector wires. | 04-01-2010 |
20100218614 | Measurement Element - An object of the present invention is to provide a structure unlikely to break in the dicing process while allowing easy execution of screening, for a measurement element in which a resistor constituting a heater is formed on a thin wall part thermally insulated from a semiconductor substrate by providing a cavity part formed in the semiconductor substrate. | 09-02-2010 |
20100242591 | Thermal-Type Flowmeter - The present invention provides a highly-sensitive thermal-type flow-rate sensor with enhanced reliability. Provided is a thermal-type flow-rate sensor including: a passage into which a measurement-target fluid is introduced; and a sensor element which is provided in the passage and which measures the flow rate of the measurement-target fluid. The sensor element | 09-30-2010 |
20100275685 | Thermal Air Flowmeter - An object of the invention is to provide a thermal air flowmeter which can reduce a detection error occurring during pulsating air flow due to a difference of response between rising and falling of detected flow or due to air flow dependence of response. A thermal air flowmeter | 11-04-2010 |
20110048127 | Thermal Humidity Sensor - Provided is a high-precision, mechanically robust thermal humidity sensor. A detecting element | 03-03-2011 |
20110072897 | Heating Resistance Type Air Flow Rate Measuring Device - A temperature of the heating resistor is set at a temperature equal to or higher than a temperature, at which liquid droplets contacting a surface of the heating resistor evaporate and disappear by film boiling. Alternatively, when a heating resistance type air flow rate measuring device starts to operate or stops operating, the temperature of the heating resistor may be set at a temperature equal to or higher than the temperature, at which liquid droplets contacting a surface of the heating resistor evaporate and disappear by film boiling. Moreover, a water-repellent and oil-repellent protective coating may be provided on the surface of the heating resistor. | 03-31-2011 |
20110140211 | Flow Sensor, Method for Manufacturing Flow Sensor and Flow Sensor Module - The invention provides a flow sensor structure for sealing the surface of an electric control circuit and a part of a semiconductor device via a manufacturing method capable of preventing occurrence of flash or chip crack when clamping the semiconductor device via a mold. The invention provides a flow sensor structure comprising a semiconductor device having an air flow sensing unit and a diaphragm formed thereto, and a board or a lead frame having an electric control circuit for controlling the semiconductor device disposed thereto, wherein a surface of the electric control circuit and a part of a surface of the semiconductor device is covered with resin while having the air flow sensing unit portion exposed. The invention further provides flow sensor structure in which surfaces of a resin mold, a board or a pre-mold component surrounding the semiconductor device are continuously not in contact with three walls of the semiconductor device orthogonal to a side on which the air flow sensing unit portion is disposed, or a manufacturing method for absorbing the dimensional variation of the semiconductor device by the deformation of springs or deformation of an elastic film in the thickness direction. | 06-16-2011 |
20110154885 | Thermal Gas Sensor - The present invention provides a high-responsiveness and high-accuracy thermal gas sensor configured to enable gas to be analyzed based on a variation in heat conductivity. The thermal gas sensor includes a substrate | 06-30-2011 |
20120055245 | Thermal Air Flow Sensor - In a thermal air flow sensor according to the invention, a hollow formed in a detecting element is communicated with a circuit chamber, in which driving circuit parts of the detecting element are mounted, or an intake duct exterior. Thereby, pressure in the hollow balances with pressure on the outside. Also, since the circuit chamber is provided to be isolated from a detection chamber, in which a detecting part of the detecting element is arranged, that is, a passage chamber, through which air being a measuring object flows, air flowing in the passage chamber can be restrained from flowing into the hollow to have an influence on flow output characteristics. | 03-08-2012 |
20120160024 | INTAKE TEMPERATURE SENSOR - An intake temperature sensor capable of precisely detecting the temperature of intake at high speed even in a low air mass flow zone is provided. In an intake temperature sensor having a temperature detecting element | 06-28-2012 |
20120192632 | Intake Air Temperature Sensor and Thermal Airflow Meter Including the Same - An intake air temperature sensor capable of detecting an intake air temperature highly accurately and at high speed. The intake air temperature sensor of the present invention includes: a secondary passage | 08-02-2012 |
20120192644 | Thermal Flow Sensor - A thermal flow sensor includes a heater temperature controller that realizes stable startup characteristics and prevents degradation of a sensor element and can also accommodate a smaller heater. The sensor also includes a semiconductor substrate; a cavity portion provided in the semiconductor substrate; a dielectric film provided on the semiconductor substrate; a thin layer area formed as a result of the dielectric film covering the cavity portion; a heating resistor provided in the thin layer area on the dielectric film; a first temperature-sensitive resistor provided in the thin layer area on the dielectric film; a heating controller; a second temperature-sensitive resistor provided near the heating resistor; and a flow rate detector that detects a flow rate of a fluid on the basis of temperature of the second temperature-sensitive resistor. The heating controller controls the temperature of the heating resistor on the basis of first and second reference temperatures. | 08-02-2012 |
20120198925 | Sensor Structure - In relation to a humidity sensor sensitive to water and contamination, a sensor implementation structure that achieves both protection performance against water and contaminants and measurement performance such as humidity responsiveness is provided. A sensor structure has a mass airflow measurement element that measures a mass airflow flowing in an intake pipe, a humidity sensing element that senses humidity of air flowing in the intake pipe, a housing structural component having a connector that carries out input/output to/from outside and a terminal component of the connector, and a bypass passage that is composed by using part of the housing structural component and takes in part of the air that flows in the intake pipe, the mass airflow measurement element being mounted in the bypass passage; wherein space is provided in the housing structural component in the vicinity of the bypass passage, the humidity sensing element is mounted in the space. | 08-09-2012 |
20120198943 | Sensor Structure - A sensor structure is provided so that a dynamic pressure effect caused by airflow is avoided as much as possible even when a mass airflow measurement device is integrated with a pressure measurement device, thereby preventing contaminated substances, water droplets, or the like from arriving at a pressure measurement part. In the sensor structure, the mass airflow measurement device is inserted into a sensor insertion port provided in an intake air tube component including an intake air tube and is fixed to the intake air tube, and a pressure measurement device is mounted in a housing structural component of the mass airflow measurement device for measuring the pressure. The pressure measurement device and the inside of the intake air tube are connected by a pressure intake port provided in the housing structural component. | 08-09-2012 |
20130025363 | Thermal Type Flow Rate Sensor - To reduce a signal variation of a bridge circuit connected with a temperature sensing resistor that is caused by a strain even when the strain is generated at a diaphragm portion of a substrate installed with a heater resistor and the temperature sensing resistor. In a thermal type flow rate resistor including a substrate, a diaphragm | 01-31-2013 |
20130093432 | Disconnection Detection Circuit for Bridge Circuit and System Including Disconnection Detecting Means - In an existing disconnection detection circuit for a bridge circuit, consideration is not taken into the fact that an offset voltage or temperature characteristic of a bridge output is degraded. Provided is a disconnection detection circuit for a bridge circuit capable of suppressing a change in a characteristic of a sensor to a minimal extent. A disconnection detection circuit | 04-18-2013 |
20130119504 | Thermal Airlflow Sensor - An object of the present invention is to provide a thermal airflow sensor that prevents moisture absorption by a silicon oxide film formed closest to a surface (formed to be located on an uppermost portion), and that reduces a measuring error. In order to attain the foregoing object, the thermal airflow sensor according to the present invention applies an ion implantation to a silicon oxide film | 05-16-2013 |
20130152699 | Gas Flow Rate Measurement Device - Provided is a highly accurate, highly reliable gas flow rate measurement device that provides an enlarged temperature range over which the resolution at a high temperature and at a low temperature can be increased to achieve high accuracy no matter whether the characteristics of a gas temperature detection element are nonlinear. The gas flow rate measurement device includes a plurality of resistors that are disposed in a gas flow path, a gas flow rate detection circuit that outputs a gas flow rate detection signal in accordance with the flow rate of a gas flowing in the gas flow path by detecting a current flowing in the resistors or by detecting a voltage generated in accordance with the current, and a gas temperature detection element | 06-20-2013 |
20130192388 | Flow Sensor and Manufacturing Method of the Same and Flow Sensor Module and Manufacturing Method of the Same - Technique of suppressing performance variations for each flow sensor is provided. In a flow sensor FS | 08-01-2013 |
20130199280 | Thermal Flow Meter - An object of the present invention is to provide a thermal type flow rate sensor that offers high sensitivity and improved reliability. A sensor element according to the present invention includes a semiconductor substrate, a cavity portion formed on the semiconductor substrate, a heating resistor formed on the cavity portion via an electrically insulating film, a heating temperature sensor for detecting heating temperature of the heating resistor, and a driving circuit for controlling the heating temperature of the heating resistor using the temperature detected by the heating temperature sensor. The heating temperature sensor comprises temperature-sensitive resistors having resistance values varying according to temperature and disposed upstream and downstream of a direction of flow of a fluid to be measured relative to the heating resistor and on upper and lower sides in a direction perpendicular to the direction of flow of the fluid to be measured relative to the heating resistor. | 08-08-2013 |
20130313675 | Thermal Type Flowmeter - Provided is a compact thermal type flowmeter that can perform a partial thermal treatment on a sensor element portion without affecting other elements and can improve the reliability of a sensor element while improving the sensitivity of the sensor element. | 11-28-2013 |
20140109691 | Flow Sensor and Manufacturing Method of the Same and Flow Sensor Module and Manufacturing Method of the Same - Technique of suppressing performance variations for each flow sensor is provided. In a flow sensor FS | 04-24-2014 |
20140190273 | Flow Sensor and Manufacturing Method of the Same and Flow Sensor Module and Manufacturing Method of the Same - Technique of suppressing performance variations for each flow sensor is provided. In a flow sensor FS | 07-10-2014 |