Denso Corporation

Nippon Soken, Inc.

Yoshiharu Nonoyama

Naoyuki Yamada

Tsukasa Kuboshima

Takeshi Hashizume

Fumiaki Arikawa

Niro Takaki

Hiroyasu Kanamori

Katsuhiro Ichihashi

An apparatus extracts a main waveform component and a branch waveform component from a pressure waveform detected by a fuel pressure sensor. The main waveform component is caused by pressure change traveling in a main passage. The branch waveform component is caused by pressure change traveling in a branch passage. The apparatus calculates traveling speeds based on the components. Then, the apparatus estimates a main passage temperature based on a detected value of the fuel temperature sensor, the traveling speeds, the fuel pressure waveform and an average pressure.

Apparatus of estimating fuel state

A fuel injection system has a fuel injector and a fuel pressure sensor. An ECU acquires a pressure waveform detected by the fuel pressure sensor during performing a multi-stage injection as a detected waveform at the time of the multi-stage injection, memorizes a model waveform, which is used as a standard of the pressure waveform when an injection that is preceding an target injection is performed without performing the target injection when any one of an injection of a second stage or later of an injection is considered as the target injection among multi-stage injections, and extracts the pressure waveform resulting from the target injection by deducting the model waveform from the detected waveform at the multi-stage injection. The ECU corrects the model waveform used for extraction by a ratio according to a maximum injection rate in the injection of the preceding stage.

Fuel pressure waveform acquisition device

A first resilient member generates a resilient force to urge a valve portion in a valve-closing direction. A second resilient member generates a resilient force against the resilient force of the first resilient member. The resilient force of the first resilient member and the resilient force of the second resilient member are set to be balanced with each other when the valve portion is placed in a lift position that is between a full-closing position of the valve portion, in which the valve portion is seated against a valve seat to fully close a fluid passage, and a full-opening position of the valve portion, in which the valve portion is fully lifted away from the valve seat to fully open the fluid passage.

Pressure control apparatus

A fuel-pressure waveform detector has a detect-waveform obtaining unit for obtaining a multi-stage injection pressure waveform by means of a fuel-pressure sensor while performing a multi-stage fuel injection during one combustion cycle. A model waveform memory stores a reference model pressure waveform of when a single fuel injection is performed. A waveform extracting unit extracts a pressure waveform due to the subject fuel injection by subtracting the reference model pressure waveform from the multi-stage injection pressure waveform. A correction unit corrects the reference model pressure waveform in such a manner that its attenuation degree becomes larger as a fuel injection period of the subject fuel injection is longer.

Fuel-pressure waveform detector

A filter is arranged in an exhaust passage of an engine. The filter supports a catalyst. An accumulating amount estimating means detects differential pressure of the filter to estimate an amount of soot accumulating on the filter. An oxidizing condition detecting means detects an oxidizing condition of soot accumulating on the filter. A forcible oxidizing means increases temperature of the filter more than oxidizing temperature of soot for forcibly oxidizing soot accumulating in the vicinity of the catalyst of the filter. When the oxidizing condition detecting means detects a condition, in which soot accumulating on the filter is only partially oxidized, the accumulating amount estimating means estimates the amount of soot accumulating on the filter after oxidizing soot accumulating in the vicinity of the catalyst using the forcible oxidizing means.

Growing community of inventors

Nagoya, Japan

Yoshiharu Nonoyama