Patents by Inventor Shigeto Yahata
Shigeto Yahata has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Publication number: 20070125076Abstract: An exhaust gas purifying apparatus for a diesel engine has a filter provided in an exhaust pipe of the engine for trapping diesel particulates contained in exhaust gas. The filter is re-generated when an accumulated amount of the diesel particulates exceeds a predetermined value. An electronic control unit estimates the accumulated amount of the diesel particulates from a pressure loss at the filter, based on an accumulation characteristic in which the pressure loss is related to the accumulated amount of the diesel particulates, and corrects the accumulation characteristic depending on flow velocity of the exhaust gas.Type: ApplicationFiled: November 30, 2006Publication date: June 7, 2007Applicant: DENSO CORPORATIONInventors: Satoru Nosaka, Kazuharu Tochikawa, Shigeto Yahata
-
Publication number: 20070107390Abstract: An exhaust gas purifying apparatus for an internal combustion engine includes a collector, a differential pressure sensing device, a differential pressure based estimating device, a partition wall exposure sensing device, and a second regenerating device. The collector captures exhaust particles in exhaust gas. The differential pressure sensing device senses a differential pressure across the collector. The differential pressure based estimating device estimates an accumulation amount of the exhaust particles based on the differential pressure. The partition wall exposure sensing device senses a partition wall exposure state. The second regenerating device forcibly completely combusts the exhaust particles captured in the collector when the partition wall exposure sensing device senses the partition wall exposure state.Type: ApplicationFiled: November 14, 2006Publication date: May 17, 2007Applicant: DENSO CORPORATIONInventors: Youhei Morimoto, Tsukasa Kuboshima, Shigeto Yahata
-
Publication number: 20070101697Abstract: A method is disclosed for estimating an amount of deposited particulates (PM) in a collector of an internal combustion engine. The method includes estimating the amount of inflow of PM into the collector and estimating a basic amount of decreased PM that flows into the collector and is burned and decreased. The method also includes estimating the amount of ash deposited on the collector. The method further includes correcting the basic amount of decreased PM based on the estimated amount of ash. Moreover, the method includes estimating an amount of deposited PM by a history expression based on the estimated amount of inflow of PM and the corrected amount of decreased PM. A related device is also disclosed.Type: ApplicationFiled: November 9, 2006Publication date: May 10, 2007Applicant: DENSO CORPORATIONInventors: Shigeto Yahata, Tsukasa Kuboshima, Satoru Nosaka, Kazuharu Tochikawa
-
Patent number: 7197868Abstract: An electronic control unit estimates progress of growth in a particle diameter of an ash accumulated in a diesel particulate filter (a DPF), based on an operating state of an engine. If it is determined that an estimated particle diameter of the ash achieved through the progress of the growth is greater than a predetermined value, regeneration of the DPF is compulsorily performed even when a quantity of particulate matters accumulated in the DPF is lower than a reference value, at which the DPF should be regenerated. Thus, the particulate matters are eliminated through combustion, and the ashes are discharged from the DPF.Type: GrantFiled: August 24, 2004Date of Patent: April 3, 2007Assignee: Denso CorporationInventors: Shigeto Yahata, Makoto Saito, Masumi Kinugawa
-
Publication number: 20070051099Abstract: An exhaust gas purifying apparatus for an internal combustion engine includes a collector, which collects exhaust particles in exhaust gas discharged from the internal combustion engine. The exhaust gas purifying apparatus computes an amount of a predetermined gas component in the exhaust gas, which passes through the collector. The exhaust gas purifying apparatus computes a collected amount of the exhaust particles based on a pressure difference across the collector, based on a temperature of the exhaust gas, which passes through the collector, and based on the amount of the predetermined gas component. The exhaust gas purifying apparatus regenerates the collector by burning the exhaust particles collected in the collector when the collected amount reaches a predetermined value.Type: ApplicationFiled: September 6, 2006Publication date: March 8, 2007Applicant: DENSO CORPORATIONInventors: Kazuharu Tochikawa, Satoru Nosaka, Shigeto Yahata
-
Publication number: 20070044459Abstract: An exhaust gas purifying apparatus for an internal combustion engine includes a collector, which collects exhaust particles in exhaust gas. The apparatus computes a pressure-difference-based measured value of a collected amount of the particles based on a pressure difference, and computes a pressure-difference-based estimated value by correcting the measured value. The apparatus computes an operational-state-based estimated value of the collected amount. The apparatus regenerates the collector by burning the exhaust particles when one of the pressure-difference-based estimated value and the operational-state-based estimated value reaches a predetermined value.Type: ApplicationFiled: September 1, 2006Publication date: March 1, 2007Applicant: DENSO CORPORATIONInventors: Yasuhiro Kariya, Shigeto Yahata, Tsukasa Kuboshima, Masumi Kinugawa, Kanehito Nakamura
-
Patent number: 7171803Abstract: An electronic control unit (ECU) calculates a pressure loss in an exhaust passage downstream of a diesel particulate filter (DPF) fluctuating in accordance with an operating state of an engine based on the operating state as a pressure loss in the exhaust passage constituting a part of a difference between an atmospheric pressure and an absolute pressure of exhaust gas flowing through the DPF. The ECU converts a mass flow rate of the exhaust gas flowing through the DPF into a volumetric flow rate based on the obtained absolute pressure. Thus, the volumetric flow rate can be calculated correctly regardless of fluctuation in the operating state, and a deposition state of exhaust particulate matters can be calculated highly accurately. Thus, regeneration of the DPF can be performed at appropriate timing.Type: GrantFiled: February 10, 2005Date of Patent: February 6, 2007Assignee: Denso CorporationInventors: Makoto Saito, Shigeto Yahata
-
Publication number: 20070012034Abstract: In an exhaust emission control system for a vehicular internal combustion engine, a particulate filter collects particulate matters in an exhaust gas of the internal combustion engine. A filter regenerator regenerates the particulate filter by burning the particulate matters accumulated in the particulate filter. A filter front clogging detector determines whether a front end portion of the particulate filter is clogged by the particulate matters. A filter regeneration controller that controls the filter regenerator to perform a front regeneration to remove the particulate matters accumulated in the front end portion of the particulate filter when the filter front clogging detector determines that the front end portion of the particulate filter is clogged.Type: ApplicationFiled: July 11, 2006Publication date: January 18, 2007Applicant: DENSO CORPORATIONInventors: Shigeto Yahata, Kazuharu Tochikawa, Tsukasa Kuboshima
-
Patent number: 7162867Abstract: An exhaust gas purifying device for an engine includes a particulate filter midway in an exhaust passage for collecting particulate matters. A control means calculates an accumulating amount of particulate matters on the particulate filter. An accumulating amount calculating means calculates the accumulating amount in accordance with an accumulating characteristic and differential pressure of the particulate filter detected using a differential pressure detecting means. When the accumulating amount becomes a predetermined regeneration demand amount, the control means performs a forcible regeneration, in which particulate matters on the particulate filter are burned and removed to regenerate the particulate filter.Type: GrantFiled: September 19, 2005Date of Patent: January 16, 2007Assignee: Denso CorporationInventors: Makoto Saito, Shigeto Yahata, Kazuharu Tochikawa, Kanehito Nakamura, Tsukasa Kuboshima
-
Patent number: 7159390Abstract: To prevent the deterioration of catalyst or the damage of a particulate filter caused by the rapid temperature rise of the particulate filter when the abrupt deceleration of an engine occurs, and avoid the deterioration of fuel consumption by depositing a large PM in the particulate filter and regenerating the same at once. A heat-absorbing area 4 is provided by forming a deeply clogged structure at the exhaust gas flowing-out side end of the particular filter 1 disposed in an exhaust pipe 2 of an internal combustion engine E. As the heat-absorbing area has a heat capacity larger than that in the other portions, the combustion heat is absorbed and dispersed even if the rapid chain reaction of PM combustion occurs, whereby it is possible to suppress the temperature rise of the downstream portion of the particulate filter liable to be high in temperature.Type: GrantFiled: June 15, 2004Date of Patent: January 9, 2007Assignee: Denso CorporationInventors: Makoto Saito, Shigeto Yahata, Kazuharu Tochikawa, Kojiro Tokuda
-
Patent number: 7146804Abstract: An exhaust gas cleaning system for a diesel engine has a diesel particulate filter (DPF) disposed in an exhaust pipe. An electronic control unit of the system controls regeneration of the DPF. The DPF is heated and regenerated only when an operating state of the engine is in an area where temperature-increasing efficiency is high, in the case where a quantity of particulate matters collected by the DPF is equal to or greater than a first threshold and is less than a second threshold. The second threshold is greater than the first threshold. If the quantity of the collected particulate matters becomes equal to or greater than the second threshold, the regeneration is performed even if the operating state is not in the area of the high temperature-increasing efficiency.Type: GrantFiled: June 13, 2003Date of Patent: December 12, 2006Assignee: Denso CorporationInventors: Shigeto Yahata, Makoto Saito, Tsukasa Kuboshima, Shinichiro Okugawa
-
Publication number: 20060225409Abstract: A diesel particulate filter (DPF) for trapping exhaust particulates is located in an exhaust passage of a diesel engine. Deposit amounts of a soluble organic fraction (SOF) as an organic solvent soluble component and soot as a solid carbon component of exhaust particulate components deposited in the DPF are estimated respectively. When the SOF deposit amount reaches an SOF elimination execution deposit amount, the DPF is heated to or over relatively low SOF combustion temperature to execute SOF elimination treatment. When the soot deposit amount reaches a soot elimination execution deposit amount, the DPF is heated to or over relatively high soot combustion temperature to execute soot elimination treatment. The SOF elimination treatment is executed before the SOF becomes excessive to prevent rapid combustion of the soot due to combustion of the SOF.Type: ApplicationFiled: April 7, 2006Publication date: October 12, 2006Applicant: DENSO CORPORATIONInventors: Tsukasa Kuboshima, Shigeto Yahata, Kazuharu Tochikawa
-
Publication number: 20060179826Abstract: An exhaust gas purification system has a first accumulation quantity estimation device that estimates an accumulation quantity of exhaust particulate matters collected by a diesel particulate filter (DPF) based on a flowing state of exhaust gas and a second accumulation quantity estimation device that estimates the accumulation quantity based on an operating state of an engine. The first estimation device is employed only when a flow rate of the exhaust gas is equal to or greater than a predetermined value and the engine is in a steady operating state. Otherwise, the second estimation device is employed. The exhaust gas flow rate is increased if the estimation by the second estimation device continues for a long time. Thus, an opportunity to perform the accumulation quantity estimation with the first estimation device is increased, and accumulation accuracy is improved.Type: ApplicationFiled: January 19, 2006Publication date: August 17, 2006Applicant: Denso CorporationInventors: Tsukasa Kuboshima, Shigeto Yahata
-
Patent number: 7051519Abstract: The amount of accumulated particulate matter, which is accumulated in a particulate filter, is computed based on the amount of exhausted particulate matter, which is exhausted from an engine, and the amount of reduced particulate matter, which is reduced in the filter. The amount of reduced particulate matter includes the amount of reduced particulate matter, which is reduced through oxidizing reaction of the accumulated particulate matter with NO2. At the time of computing this amount, reduction of the particulate matter through oxidizing reaction with adsorbed NO2, which is adsorbed by the accumulated particulate matter, is concerned in addition to reduction of the particulate matter through oxidizing reaction with NO2, which is present in the surrounding atmosphere around the accumulated particulate matter.Type: GrantFiled: July 19, 2005Date of Patent: May 30, 2006Assignee: Denso CorporationInventors: Tsukasa Kuboshima, Kanehito Nakamura, Makoto Saito, Shigeto Yahata, Kazuharu Tochikawa
-
Publication number: 20060059901Abstract: An exhaust gas purifying device for an engine includes a particulate filter midway in an exhaust passage for collecting particulate matters. A control means calculates an accumulating amount of particulate matters on the particulate filter. An accumulating amount calculating means calculates the accumulating amount in accordance with an accumulating characteristic and differential pressure of the particulate filter detected using a differential pressure detecting means. When the accumulating amount becomes a predetermined regeneration demand amount, the control means performs a forcible regeneration, in which particulate matters on the particulate filter are burned and removed to regenerate the particulate filter.Type: ApplicationFiled: September 19, 2005Publication date: March 23, 2006Applicant: Denso CorporationInventors: Makoto Saito, Shigeto Yahata, Kazuharu Tochikawa, Kanehito Nakamura, Tsukasa Kuboshima
-
Publication number: 20060048507Abstract: In an exhaust gas purifying apparatus for a diesel engine having a diesel particulate filter provided in an exhaust pipe, a pressure loss at the filter is detected. An accumulated amount of diesel particulates in the filter is calculated based on the pressure loss and a map for a relationship between the pressure loss and the accumulated amount. A compulsory re-generating operation is carried out when the calculated accumulated amount reaches at a predetermined threshold value, which is decreased to a smaller value depending on a combustion amount of the diesel particulates which are combusted and removed from the filter as a natural re-generating operation.Type: ApplicationFiled: September 8, 2005Publication date: March 9, 2006Applicant: Denso CorporationInventors: Kazuharu Tochikawa, Makoto Saito, Shigeto Yahata, Tsukasa Kuboshima, Kanehito Nakamura
-
Publication number: 20060021334Abstract: The amount of accumulated particulate matter, which is accumulated in a particulate filter, is computed based on the amount of exhausted particulate matter, which is exhausted from an engine, and the amount of reduced particulate matter, which is reduced in the filter. The amount of reduced particulate matter includes the amount of reduced particulate matter, which is reduced through oxidizing reaction of the accumulated particulate matter with NO2. At the time of computing this amount, reduction of the particulate matter through oxidizing reaction with adsorbed NO2, which is adsorbed by the accumulated particulate matter, is concerned in addition to reduction of the particulate matter through oxidizing reaction with NO2, which is present in the surrounding atmosphere around the accumulated particulate matter.Type: ApplicationFiled: July 19, 2005Publication date: February 2, 2006Applicant: Denso CorporationInventors: Tsukasa Kuboshima, Kanehito Nakamura, Makoto Saito, Shigeto Yahata, Kazuharu Tochikawa
-
Patent number: 6969413Abstract: A flow rate of gas supplied to a diesel particulate filter is increased when it is determined that rapid combustion of collected particulates, which are collected by the particulate filter, is likely to occur based on an operating state of an internal combustion engine. Alternatively, the flow rate of gas supplied to the filter is increased when it is determined that rapid combustion of the collected particulates is initiated based on a state of the particulate filter.Type: GrantFiled: June 12, 2003Date of Patent: November 29, 2005Assignee: Denso CorporationInventors: Shigeto Yahata, Makoto Saito, Tsukasa Kuboshima, Shinichiro Okugawa, Masumi Kinugawa
-
Patent number: 6966178Abstract: An amount ML of particles accumulated in small holes of a particulate filter is calculated in accordance with a pressure drop ?P detected by a pressure sensor and a characteristic line. The characteristic line is defined by a first characteristic line and a second characteristic line, which is defined after exceeding a transition point TP. When the particles accumulated in the small holes are burned while remaining accumulated particles on the surface, the second characteristic line is shifted in a parallel fashion and compensated. Thus, the characteristic line is corrected so that the accumulation amount ML can be precisely calculated, even if particles accumulated in small holes are burned and the characteristic is changed.Type: GrantFiled: March 3, 2004Date of Patent: November 22, 2005Assignee: Denso CorporationInventors: Makoto Saito, Shigeto Yahata, Kazuharu Tochikawa
-
Patent number: 6962046Abstract: An electronic control unit (ECU) of an exhaust gas cleaning system for an internal combustion engine having a diesel particulate filter (DPF) determines whether collection quantity of exhaust particulate matters collected by the DPF is greater than a regeneration start value or not. The collection quantity is calculated from a pressure difference at the DPF and a flow rate of exhaust gas. If the collection quantity is determined to be greater than the regeneration start value, the ECU increases the temperature of the DPF to regenerate the DPF. The regeneration start value is set smaller as the detection accuracy of the collection quantity decreases. The regeneration start value is set smaller as the exhaust gas flow rate decreases and a rate of change in an accelerator position increases.Type: GrantFiled: June 16, 2003Date of Patent: November 8, 2005Assignee: DENSO CorporationInventors: Tsukasa Kuboshima, Shinichiro Okugawa, Makoto Saito, Shigeto Yahata