Toyota Jidosha Kabushiki Kaisha

Denso Corporation

Akio Matsunaga

Shigeki Nakayama

Yasuyuki Terada

Mitsuhiro Nada

Makoto Suzuki

Takao Fukuma

Eiichi Ono

Tomihisa Oda

Masatomo Yoshihara

Yoshiyasu Ito

Satoshi Masuda

Tomomi Onishi

Makio Tsuchiyama

Tomoyuki Ono

Shizuo Abe

Toshio Suematsu

Eiichi Yasuda

Teruhiko Miyake

Masanori Shimada

Hiroshi Enomoto

Masato Katsuno

Takeshi Miyaura

Satoshi Takamoto

Yusuke Nozaki

Yasuo Harada

Yusuke Saigo

Kazukata Takei

Masahiko Mizuno

Akiyuki Iemura

Mitsuteru Kokubun

Masayoshi Ota

Yoshitsugu Suzuki

Hidenobu Nakamura

Noriyoshi Terazawa

Eiichi c/o KK Toyota Chuo Kenkyusho Ono

Kazukata c/o KK Toyota Chuo Kenkyusho Takei

Mitsuteru c/o KK Toyota Chuo Kenkyusho Kokubun

Noriyoshi KK Toyota Chhuo Kenkyusho Terazawa

Eiichi c/o KK Toyota Chuo Kenkyusho Yasuda

Masahiko c/o KK Toyota Chuo Kenkyusho Mizuno

An exhaust gas recirculation device of an internal combustion engine () including a low-pressure EGR passage (), a high-pressure EGR passage (), a low-pressure EGR valve () and a high-pressure EGR valve () further includes an air-fuel ratio sensor () that is disposed in the exhaust passage () upstream of the position of its connection with the low-pressure EGR passage (). In the case where a predetermined fuel-cut condition is satisfied, an ECU () estimates the flow amounts of exhaust gas flowing in the low-pressure EGR passage () and the high-pressure EGR passage (), on the basis of the oxygen concentrations acquired by the air-fuel ratio sensor () at timings at which the exhaust gases recirculated into the intake passage () via the low-pressure EGR passage () and via the high-pressure EGR passage () reach the air-fuel ratio sensor (), respectively.

Exhaust gas recirculation device of internal combustion engine, and control method for the device

In an exhaust gas sensor control system and control method, the exhaust pipe wall temperature is estimated based on the measured exhaust gas temperature measured, the exhaust gas flow rate, and the measured outside air temperature, with reference to a supplied heat quantity calculation map, wall temperature added value map, and a wall temperature subtracted value map. Then the dew-point of the exhaust pipe is calculated based on the air-fuel ratio of the air flow amount to the weight of fuel, and a condensed water added amount is calculated based on the relative wall temperature and the exhaust gas flow amount. The amount of condensed water is then estimated by summing the calculated condensed water added amounts.

Exhaust gas sensor control system and control method

An exhaust gas control system for an internal combustion engine includes a turbocharger that includes a compressor arranged in an intake passage, and a turbine arranged in an exhaust passage; a low-pressure EGR unit that recirculates a portion of exhaust gas back to the internal combustion engine through a low-pressure EGR passage that provides communication between the exhaust passage, at a portion downstream of the turbine, and the intake passage, at a portion upstream of the compressor; a low-pressure EGR valve that is provided in the low-pressure EGR passage, and that changes the flow passage area of the low-pressure EGR passage; and a valve control unit that executes an opening/closing control over the low-pressure EGR valve. When it is determined that the internal combustion engine is under a predetermined low-temperature environment, the low-pressure EGR valve is kept closed while the internal combustion engine is in the fuel-supply cutoff operation mode.

Exhaust gas control system for internal combustion engine and method for controlling the same

In one embodiment, a total fuel injection amount is calculated from a torque required by an engine. A division ratio of a pre-injection amount that achieves both suppression of ignition delay of fuel from a main injection and suppression of a peak value of a heat production ratio of combustion from the main injection is calculated. Upper and lower limit guards are given to the obtained divided amount, and the divided injection amount is calculated. The injection amount of the main injection is obtained by subtracting the divided injection amount from the total fuel injection amount.

Fuel injection control apparatus of internal combustion engine

In one embodiment, a determination is made of whether or not in a condition in which a compressed gas temperature will reach a fuel self-ignition temperature by only a compression operation in the compression stroke, and in a case where the compressed gas temperature will reach the fuel self-ignition temperature, pilot injection is judged to be unnecessary, so this pilot injection is prohibited.

A cetane number estimation method is provided in which: the preliminary injection is preformed multiple times at different compression end temperatures with a fuel tank () containing fuel having a predetermined cetane number, and an engine torque increase caused by each preliminary injection is calculated and the relation between the compression end temperatures at the respective preliminary injections and the engine torque increases caused by the respective preliminary injections is determined; the compression end temperature and the engine torque increase at a predetermined reference point on the relation are recorded as a basic compression eng temperature and a basic engine toque increase; the preliminary injection is performed at the basic compression end temperature and an engine torque increase caused by this preliminary injection is calculated; and the cetane number of fuel is estimated based on the relation between the calculated engine torque increase and the basic engine torque increase.

Cetane number estimation method

A technique is provided which, in an exhaust gas recirculation apparatus for an internal combustion engine, can calculate a low-pressure EGR rate and a high-pressure EGR rate in an accurate manner, and control the flow rates of both a low pressure EGR passage and a high pressure EGR passage in a closed-loop control manner, thereby to make the temperature of intake air and a supercharging pressure stable and to suppress the deterioration of exhaust emissions as well as the deterioration of power performance. The low pressure EGR rate, representative of the proportion of an amount of low pressure EGR gas to an amount of intake air sucked into the internal combustion engine, and the high pressure EGR rate, representative of the proportion of an amount of high pressure EGR gas to the amount of intake air, are calculated by using a COconcentration in an intake passage at a location downstream of a connection portion of the low pressure EGR passage and upstream of a connection portion of the high pressure EGR passage, a COconcentration in the intake passage at a location downstream the connection portion of the high pressure EGR passage, and a COconcentration of an exhaust gas discharged from the internal combustion engine (S). The low pressure EGR rate and the high pressure EGR rate to be calculated are controlled to individual target values, respectively (S).

Exhaust gas recirculation apparatus for an internal combustion engine

The present invention provides an acceleration sensation evaluating device that evaluates a sensory acceleration of a driver with respect to an expectation value of acceleration, and a vehicle controller that controls a vehicle according to the evaluation results. The evaluation device detects an amount of operation of the vehicle by the driver of when the vehicle is accelerated, detects an amount of vehicle behavior, computes a physical quantity of an expectation value indicating the expectation value of an acceleration performance which the driver expects based on the detected values, computes a sensory physical quantity indicating a sensation of the acceleration which the driver senses, and computes an evaluation value of the acceleration sensation based on difference or ratio between the physical quantity of the expectation value and the sensory physical quantity.

Acceleration sensation evaluating device and vehicle controller

The invention provides a fuel injection control device for an internal combustion engine that can improve the accuracy of combustion control regarding smoke suppression. The fuel injection control device is applied to an engine provided with an EGR device for returning, as a part of an intake gas flown into the cylinder, an EGR gas, withdrawn from an exhaust passage, to an air intake passage. The amount of oxygen OXM contained in the intake gas and the concentration of oxygen OXC contained in the intake gas are detected (steps Sand S). The smoke tolerable limit value QOXMLMT as the upper limit of the amount of fuel injection, which can suppress the amount of smoke generated in the engine to a predetermined tolerance range, is set based on the detected amount of oxygen and concentration of oxygen (step S), and, when the required amount of injection QDMD determined based on operation conditions is larger than the tolerable limit value QOXMLMT, the instructional injection amount QFIN is limited to the tolerable limit value QOXMLMT.

Fuel injection control device for internal combustion engine

An EGR control device is provided with an EGR control valve () and an electronic control unit (). An exhaust gas recirculation pipe () extends across the EGR control valve (). The electronic control unit calculates a target EGR ratio, a target air flow rate, an actual EGR ratio, and an actual air flow rate, on the basis of operational state quantities of an engine. The electronic control unit then calculates, as a target converted EGR ratio, a ratio of the target EGR ratio to the target air flow rate, calculates, as an actual converted EGR ratio, a ratio of the actual EGR ratio to the actual air flow rate, and controls an opening of the EGR control valve such that the target converted EGR ratio becomes equal to the actual converted EGR ratio. An actual converted EGR ratio is proportional to an intake-air oxygen concentration, and an actual converted EGR ratio and a target converted EGR ratio are calculated independently of a command injection amount. Therefore, a desired intake-air oxygen concentration is obtained irrespective of flow rate characteristics of injection valves.

EGR control device and method for internal combustion engine

An EGR-gas temperature estimation apparatus for an internal combustion engine which has an exhaust circulation pipe and an EGR-gas cooling apparatus. The estimation apparatus obtains the cooling efficiency &#x3b7;egr of the EGR-gas cooling apparatus from the temperature Tex of EGR gas at the inlet of the exhaust circulation pipe and the flow rate Gegr of the EGR gas, and obtains the temperature THW of engine cooling water, used as a coolant for the EGR-gas cooling apparatus. Subsequently, the estimation apparatus calculates the temperature Tegr of the EGR gas at the outlet of the exhaust circulation pipe by the expression Tegr=Tex&#x2212;&#x3b7;egr&#xb7;(Tex&#x2212;THW). Since the cooling efficiency &#x3b7;egr greatly changes depending on the EGR-gas flow rate Gegr and the EGR-gas temperature Tex, the estimation apparatus can accurately estimate the cooling efficiency &#x3b7;egr, and therefore can accurately estimate the EGR-gas temperature Tegr.

EGR-gas temperature estimation apparatus for internal combustion engine

A control apparatus for a motor vehicle is provided in which each of a plurality of output values of the vehicle varies depending upon a plurality of input control parameters for controlling the vehicle. The control apparatus changes the input control parameter or parameters so that each of the output values becomes substantially equal to a corresponding target output value. The control apparatus then determines adapted values of the input control parameters, based on values of the input control parameters obtained when each of the output values becomes substantially equal to the corresponding target output value or falls within a permissible adaptation range of the target output value.

Control apparatus for motor vehicle and storage medium

An EGR-gas flow rate estimation apparatus for an engine including an exhaust circulation pipe connected between an exhaust passage and an intake passage of the engine, and an EGR control valve interposed in the exhaust circulation pipe and having a throttle portion. The apparatus estimates a provisional EGR gas flow rate Gegrby use of a general formula Gegr=Aegr&#xb7;(2&#xb7;Pex&#xb7;&#x3c1;a)&#xb7;&#x3a6; (&#x3a6;=(((&#x3ba;/(&#x3ba;&#x2212;1)&#xb7;((Pb/Pex)&#x2212;(Pb/Pex)))) where Pup represents the exhaust pressure, Pb represents the intake pressure, Aegr represents the effective opening area of the throttle portion, &#x3c1;a represents the density of EGR gas, and &#x3ba; represents the specific heat ratio of EGR gas. Subsequently, the apparatus estimates the flow rate Gegr of EGR gas flowing into the intake passage, by multiplying the provisional EGR gas flow rate Gegrby a correction value dPgain corresponding to differential pressure (Pex&#x2212;Pb).

EGR-gas flow rate estimation apparatus for internal combustion engine

An engine is provided with a dual cooling system having a head-side cooling water passage formed in a cylinder head, through which a cooling water can be circulated, and a block-side cooling water passage formed in a cylinder block, through which a cooling water can be circulated, in which a block-side circulation can be stopped without stopping a head-side circulation. An exhaust gas recirculation control device for such engine comprises a temperature sensor for detecting a temperature of the cooling water circulating the head-side passage (THW); and an exhaust gas recirculation (EGR) system for supplying an EGR gas to the engine. The EGR system performs the supply of the EGR gas when the cooling water temperature (THW) is higher than a predetermined temperature (THE), and stops the supply of the EGR gas when the cooling water temperature (THW) is lower than the predetermined temperature (THE). The predetermined temperature when the block-side circulation is stopped (THL) is set to be different from the predetermined temperature when the block-side circulation is performed (THH).

Exhaust gas recirculation control device for engine with dual cooling

According to the present invention, there is provided a cylinder head for a multi-cylinder internal combustion engine, comprising: a bottom wall having an upper face which defines a waterjacket, the bottom wall having spaced recessed wall portions which have lower faces defining upper spaces of adjacent combustion chambers, the bottom wall having a bottom wall portion formed between the recessed wall portions to divide the upper spaces of the adjacent combustion chambers; and slit means formed on the upper face of the bottom wall portion and extending within the bottom wall portion toward a lower face of the bottom wall portion.

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Nishikamo-gun, Japan

Akio Matsunaga