Denso Corporation

Nippondenso Co., Ltd.

Denso Corpora Tion

Yasushi Kohno

Takao Ban

Hiroyuki Wado

Junzo Yamaguchi

Toshimasa Yamamoto

Ryo Nagasaka

Minoru Kondo

Makoto Tsunekawa

Tomoyuki Takiguchi

Yasushi Goka

Makiko Sugiura

Yukihiro Takeuchi

Akitoshi Mizutani

Toshiyuki Morishita

Toshiki Isogai

Hiromi Ariyoshi

Teruaki Kaifu

Masahito Mizukoshi

Takashi Ooga

Takao Iwaki

Tetsuo Yoshioka

Masaaki Konishi

Hidehito Tsujii

Hideki Koyama

Norikazu Hosokawa

Shinji Ota

Toshirou Gotou

Kiyoyuki Sugiura

Katsumi Nakashima

A communication system includes a flow measuring device and a control device. The flow measuring device includes a flow sensor that generates a flow rate signal which is a signal in accordance with a flow rate of intake air drawn into an internal-combustion engine. The flow measuring device transmits the flow rate signal. The control device receives the flow rate signal and performs at least one of injection control of fuel to be supplied to the engine and ignition control at each cylinder of the engine based on the received flow rate signal. The flow measuring device includes a measurement-side transmitting part that transmits various signals by wireless communication, and transmits the flow rate signal by the measurement-side transmitting part. The control device includes a control-side receiving part that receives the various signals by the wireless communication, and receives the flow rate signal by the control-side receiving part.

Communication system, flow measuring device and control device

A high-temperature resistance is disposed in an internal passage and has its energization controlled based on an intake-air flow rate in the passage to increase/decrease a heat generation amount. A first low-temperature resistance constitutes a bridge circuit which has its energization state changed according to the heat generation amount of the high-temperature resistance. The first low-temperature resistance varies its resistance value according to intake-air temperature. A second low-temperature resistance is an element, which is not incorporated into the bridge circuit and varies its resistance value according to intake-air temperature to increase/decrease an energization amount. The second low-temperature resistance is provided on a substrate. Another bridge circuit produces an intake air amount detection signal using an electrical signal generated by operation of the high-temperature resistance and the first low-temperature resistance. A digital circuit uses an electrical signal produced by the second low-temperature resistance as an intake temperature detection signal.

Air flow measuring device

A thermal-type air flow measuring device includes a heat generation heater and a sensor circuit. The heat generation heater is configured to heat a part of intake air drawn into an engine by heat generation upon energization of the heat generation heater. The sensor circuit is configured to at least control the energization of the heat generation heater and to make temperature of the heat generation heater higher than temperature of the heat generation heater at time of the measurement of the flow rate of air when an external signal is inputted into the sensor circuit from outside of the device.

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.

Air flow quantity measuring apparatus for internal combustion engine

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.

Air flow measurement 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.

Flow measuring device

A sensor chip in a flow quantity measuring apparatus includes 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.

Flow quantity measuring apparatus including branched conductive lines connected to midpoints of series circuits of the bridge circuit

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.

Thermal type air flow meter

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 &#x3b8; between the normal vector and the reference vector is in a range of 90 degrees&#x3c;&#x3b8;&#x3c;180 degrees.

Airflow 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.

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.

Air flow rate measuring apparatus

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.

Flow measuring device having resistors arranged in nesting arrangement

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.

Flow measuring device having heating resistor in inclined position with respect to the flow direction

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.

Flow quantity measuring device

An airflow meter has a membrane type sensor element. The sensor element is supported on a support member so that a sensing surface of the sensor element is in parallel to the airflow direction. The airflow meter has at least one means for protecting the sensor element from dust such as foreign particles. The protecting means is provided with an obstruction member that is disposed upstream or downstream of the sensor element with respect to the airflow direction. The sensor element is hidden behind the obstruction member. The obstruction member has gradually spreading surfaces and gradually converging surfaces along the airflow direction. Alternatively, the protecting means can be provided with a deflector, a cover member, a flow guide member, an inlet or a dust collector.

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Obu, Japan

Yasushi Kohno