Patent application number | Description | Published |
20080236274 | Flow measuring device - An airflow measuring device includes a sensing portion provided in a bypass passage, which perpendicularly deflects part of air from a main passage to therethrough bypass the part of air. The sensing portion includes a heating resistor energized and dissipate heat to airflow. The sensing portion is configured to measure airflow in the bypass passage based on the heat radiation. The sensing portion further includes a pair of support members erected in the bypass passage to support the heating resistor. The heating resistor of the sensing portion is inclined at a first inclination angle with respect to a direction, which is perpendicular to a flow direction of air in the bypass passage. The heating resistor is inclined toward downstream at an outer streamline of the airflow in the bypass passage. | 10-02-2008 |
20080264154 | FLOW QUANTITY MEASURING DEVICE - In a flow quantity measuring device, each of upstream side and downstream side sensing resistors, which are placed on an upstream side and a downstream side, respectively, of a heating resistor, includes resistor elements, each of which forms a folded path. The folded path has a generally constant width along an entire extent thereof and is returned at each of first and second longitudinal end edges of a sensing area. The heating resistor forms a folded path, which has a generally constant width along an entire extent thereof and is returned at the second longitudinal end edge of the heat generating area. First and second ends of the folded path of the heating resistor projects beyond the first longitudinal end edge of the sensing area on a first side of the flow quantity measuring device. | 10-30-2008 |
20080289413 | FLOW MEASURING DEVICE - According to a flow measuring device, first ranges formed by a first plurality of resistors form a single continuous value range on a flow direction coordinate axis. Thus, the first plurality of resistors is limited from being thermally insulated from one another in the flow direction, and thereby detectivity is improved. Also, second ranges formed by a second plurality of resistors form an other single continuous value range on a longitudinal direction coordinate axis. The other continuous value range includes a position that corresponds to a half length of a heating element in a longitudinal direction. As a result, detection difference is obtained at the position, at which a temperature is most optimally detected, and thereby detectivity is further improved. | 11-27-2008 |
20120079889 | AIR FLOW QUANTITY MEASURING APPARATUS FOR INTERNAL COMBUSTION ENGINE - A flow meter outputs a frequency signal, which corresponds to an air flow quantity of intake air to be supplied to an engine. In an engine control unit, when a sensed value of the air flow quantity, which is obtained based on the frequency signal, is within an estimated air flow quantity range, which is estimated based on an operational state of the engine, the sensed value of the air flow quantity is determined as a measurement value of the flow meter. In contrast, when the sensed value of the air flow quantity is out of the estimated air flow quantity range, a median of the estimated air flow quantity range is determined as the measurement value of the flow meter. | 04-05-2012 |
20120085163 | FLOW QUANTITY MEASURING APPARATUS - A first conductive line, through which a midpoint electric potential of a first series circuit of a bridge circuit is outputted, is branched from a first midpoint connection on a sensor chip. A second conductive line, through which a midpoint electric potential of a second series circuit of the bridge circuit is outputted, is branched from a second midpoint connection on the sensor chip. The output point of the midpoint electric potential of the first series circuit is provided at a midpoint between two temperature sensor resistors, and the first midpoint connection is provided on a center line of a heater resistor. The output point of the midpoint electric potential of the second series circuit is provided at a midpoint between two temperature sensor resistors, and the second midpoint connection is provided on the center line of the heater resistor. | 04-12-2012 |
20120101745 | FLOW MEASURING DEVICE - A flow measuring device includes a flow rate detecting part, an analog/digital conversion part, and a signal processing part. The flow rate detecting part detects a flow rate of air flowing through the passage, and outputs a flow voltage signal, which is a voltage in accordance with the flow rate. The analog/digital conversion part converts the flow voltage signal from the flow rate detecting part into digital data, which is flow digital data. The signal processing part performs calculation processing upon the flow digital data, which includes averaging of a predetermined number of consecutive pieces of the flow digital data, and outputs the averaged flow digital data as a flow rate signal. The predetermined number is equal to or larger than two. | 04-26-2012 |
20120240668 | AIR FLOW MEASUREMENT DEVICE - An air flow measurement device arranged in an intake passage includes a bypass passage having an inlet from which a part of a main flow of an intake air is introduced, and an outlet from which the introduced intake air flows out. A sensor is located in the bypass passage to generate an electrical signal, and the bypass passage communicates with the intake passage through a hole portion. The outlet is open toward a downstream side of the intake passage in a flow direction of the main flow of the intake air. The hole portion is located within an outlet projected area that is provided by projecting an open area of the outlet in straight and toward upstream in the flow direction of the main flow on a projection surface perpendicular to the flow direction of the main flow. | 09-27-2012 |
20120247202 | THERMAL TYPE AIR FLOW METER - A thermal type air flow meter, which detects a flow rate of air flowing in an air passage, includes a sensor portion having a heating element in an air passage, a temperature control unit. The temperature control unit includes a first arm serially connecting a first resistive element and a heater temperature detection resistor which detects a temperature of the heating element, a second arm serially connecting a second resistive element and an air temperature detection resistor which detects a temperature of air flowing in the air passage, and a voltage supply unit which supplies first and second voltages respectively to the first and second arms. The voltage supply unit includes a voltage adjusting portion which can adjust at least one of the first and second voltages such that the detection temperature difference between the heater temperature detection resistor and the air temperature detection resistor becomes constant. | 10-04-2012 |
20130036806 | AIR FLOW MEASURING DEVICE - An air flow measuring device includes a housing, flow sensor, and a humidity sensor. The housing defines a bypass flow passage through which intake it passes. A part of intake air is taken into the bypass flow passage to pass through the bypass flow passage. The flow sensor includes a sensing part disposed in the bypass flow passage, and produces a signal which is in accordance with the flow rate of intake air as a result of heat transfer between intake air taken into the bypass flow passage and the sensing part. The humidity sensor includes a sensing part exposed to the intake passage, and projects from an outer wall of the housing into the intake passage. The humidity sensor produces a signal which is in accordance with humidity of intake ail flowing through the intake passage. | 02-14-2013 |
20130055801 | AIR FLOW RATE MEASURING APPARATUS - An air flow rate measuring apparatus includes a heater and a control circuit. The heater heats a part of an intake air sucked into an engine. The control circuit controls an energization of the heater. The heater has a measuring-mode temperature when a flow rate of the intake air is measured. The control circuit has a heat cleaner which temporarily raises a temperature of the heater higher than the measuring-mode temperature when an energization of the air flow rate measuring apparatus is started. | 03-07-2013 |
20130105137 | AIR FLOW MEASURING DEVICE | 05-02-2013 |
20130192354 | AIRFLOW MEASURING DEVICE - A first passage has a branch position where a second passage is branched from the first passage to move air along a reference vector. The second passage accommodates a thermal sensor. The first passage has a throttle at a downstream of the branch position. The throttle has a throttle wall surface having a normal vector directed inwardly. A width direction is perpendicular to both a flow direction of air in the throttle and the reference vector. The throttle wall surface has a specific region, in which the normal vector includes a vector component in the width direction, and an angle θ between the normal vector and the reference vector is in a range of 90 degrees<θ<180 degrees. | 08-01-2013 |