Patents by Inventor Naoto MURASAWA

Naoto MURASAWA 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).

  • Patent number: 11499456
    Abstract: Provided are an exhaust purification device and an exhaust purification method which can achieve improved fuel efficiency. The exhaust purification device (100) is equipped with: a DOC (5) for occluding hydrocarbons in an exhaust gas; a DPF (6) that is provided downstream from the DOC (5) and is for trapping particulate matter in the exhaust gas; and an ECU (10) for determining, in accordance with the amount of occluded hydrocarbons in the DOC (5), a start time for a regeneration process for removing particulate matter accumulated in the DPF (6).
    Type: Grant
    Filed: September 4, 2019
    Date of Patent: November 15, 2022
    Assignee: Isuzu Motors Limited
    Inventors: Naoto Murasawa, Akio Nishikata, Masahiro Kajiyama, Takayuki Mukunashi
  • Publication number: 20210324773
    Abstract: Provided are an exhaust purification device and an exhaust purification method which can achieve improved fuel efficiency. The exhaust purification device (100) is equipped with: a DOC (5) for occluding hydrocarbons in an exhaust gas; a DPF (6) that is provided downstream from the DOC (5) and is for trapping particulate matter in the exhaust gas; and an ECU (10) for determining, in accordance with the amount of occluded hydrocarbons in the DOC (5), a start time for a regeneration process for removing particulate matter accumulated in the DPF (6).
    Type: Application
    Filed: September 4, 2019
    Publication date: October 21, 2021
    Applicant: Isuzu Motors Limited
    Inventors: Naoto MURASAWA, Akio NISHIKATA, Masahiro KAJIYAMA, Takayuki MUKUNASHI
  • Patent number: 10364730
    Abstract: The PM sensor includes: a filter member having a plurality of measuring cells which are defined by a porous partition wall and configured to trap particulate matter in exhaust gas; at least a pair of electrode members which are disposed to face each other with the measuring cell sandwiched therebetween to form a condenser; a heater member which heats the measuring cell to burn and remove particulate matter accumulated in the measuring cell; and an estimation unit which estimates an amount of the particulate matter contained in the exhaust gas based on an electrostatic capacity between the pair of electrode members.
    Type: Grant
    Filed: June 11, 2015
    Date of Patent: July 30, 2019
    Assignee: ISUZU MOTORS LIMITED
    Inventors: Tadashi Uchiyama, Naoto Murasawa, Satoshi Hanawa
  • Patent number: 10337434
    Abstract: The sensor includes a filter member including cells that trap PM in exhaust gas, electrode members arranged to face each other with the cell interposed and forming a capacitor, an electric heater that executes, when an amount of PM has accumulated in the cells, filter regeneration for combusting and removing the PM, a temperature sensor that acquires the temperature of the filter member, a storage unit that stores therein a reference temperature, which is the temperature of the filter member where the filter regeneration has been executed in a state in which PM is not flowing into the filter member, and estimation units that estimate a PM amount included in the exhaust gas based on (a) an electrostatic capacitance change amount between the electrode members during a regeneration interval and (b) a difference between the temperature acquired by the temperature sensor and the reference temperature during a filter regeneration interval.
    Type: Grant
    Filed: August 11, 2015
    Date of Patent: July 2, 2019
    Assignee: ISUZU MOTORS LIMITED
    Inventors: Tadashi Uchiyama, Naoto Murasawa, Satoshi Hanawa
  • Patent number: 10126205
    Abstract: The sensor includes a filter member including cells that trap PM in exhaust gas; electrode members arranged to face each other with the cell interposed and forming a capacitor, an electric heater that executes, when an amount of PM has accumulated in the cells, filter regeneration of heating the cells to combust and remove the PM, a storage unit that stores a reference reduction amount, which is an electrostatic capacitance reduction amount between the electrode members in a case where the filter regeneration is executed in a state where the PM is not flowing into the filter member, and estimation units that estimate a PM amount based on (a) an actual electrostatic capacitance change amount between the electrode members during a regeneration interval period, and (b) a difference between an actual electrostatic capacitance reduction amount between the electrode members and the reference reduction amount during a filter regeneration period.
    Type: Grant
    Filed: August 11, 2015
    Date of Patent: November 13, 2018
    Assignee: ISUZU MOTORS LIMITED
    Inventors: Tadashi Uchiyama, Naoto Murasawa, Satoshi Hanawa
  • Patent number: 10072551
    Abstract: An exhaust purification system includes: a diesel oxidation catalyst (DOC) provided on an exhaust path of an engine; an upstream diesel particulate filter (DPF) and a downstream DPF that are provided on the exhaust path at positions downstream of the DOC to collect particulate matter contained in exhaust gas; electrodes that detect a capacitance of the upstream DPF; a particulate matter accumulation estimating unit that estimates at least an amount of particulate matter accumulated in the downstream DPF on the basis of the capacitance received from the electrodes; and a forced regeneration control unit that injects fuels into the DOC and performs forced regeneration that burns and removes at least the particulate matter accumulated in the downstream DPF when the estimated amount of particulate matter from the particulate matter accumulation estimating unit surpasses a predetermined amount.
    Type: Grant
    Filed: October 8, 2014
    Date of Patent: September 11, 2018
    Assignee: ISUZU MOTORS LIMITED
    Inventors: Tadashi Uchiyama, Hidekazu Fujie, Naoto Murasawa, Satoshi Hanawa
  • Patent number: 10060829
    Abstract: A diagnosis device includes: a diesel particulate filter (DPF) collecting particulate matter (PM) in exhaust gas; a resistive type PM sensor provided downstream of the DPF, detecting an amount of PM from current flowing through PM deposited between electrodes. An actual regeneration interval calculator calculating an actual interval from completion of regeneration of the sensor to a start of the next regeneration; a PM slippage amount calculator estimating an amount of PM slippage in exhaust gas that slips through the DPF, assuming the DPF is normal; an estimated regeneration interval calculator calculating, on the basis of the PM slippage amount, an estimated interval from completion of the regeneration of the sensor to the start of the next regeneration; and a DPF failure-normal determination device determining whether the DPF has failed or is normal by comparing the actual interval to the estimated interval.
    Type: Grant
    Filed: September 26, 2014
    Date of Patent: August 28, 2018
    Assignee: ISUZU MOTORS LIMITED
    Inventors: Satoshi Hanawa, Tadashi Uchiyama, Hidekazu Fujie, Teruo Nakada, Naoto Murasawa
  • Publication number: 20180038817
    Abstract: There is provided a sensor unit 30 arranged in an exhaust system of an internal combustion engine and including a filter member 31 having a plurality of cells divided by porous partition walls and collecting particulate matter in exhaust gas, and at least one pair of electrode members 32, 33 arranged to face each other with the cell interposed therebetween so as to form a capacitor, and a control unit 40 estimating an amount of the particulate matter in the exhaust gas and detecting water present in the exhaust system of the engine, based on an electrostatic capacitance between the pair of electrode members 32, 33.
    Type: Application
    Filed: February 17, 2016
    Publication date: February 8, 2018
    Applicant: Isuzu Motors Limited
    Inventors: Tadashi UCHIYAMA, Naoto MURASAWA
  • Patent number: 9885273
    Abstract: A diagnostic device includes: a diesel oxidation catalyst (DOC) for oxidizing hydrocarbon (HC) and nitrogen monoxide in an exhaust gas; a selective catalytic reduction (SCR) catalyst for reducing and purifying NOx contained in the exhaust gas; a NOx purification rate calculation unit which calculates, based on NOx values at upstream and downstream sides of the SCR catalyst, a low temperature NOx purification rate and a high temperature NOx purification rate; a HC heat generation rate calculation unit which calculates an HC purification rate based on at least the difference between the exhaust gas heat quantities at upstream and downstream sides of the DOC; and a deterioration determination unit which determines the deterioration in the NO2 producing capability of the DOC based on the calculated low temperature NOx purification rate, the calculated high temperature NOx purification rate, and the calculated HC purification rate.
    Type: Grant
    Filed: September 18, 2014
    Date of Patent: February 6, 2018
    Assignee: ISUZU MOTORS LIMITED
    Inventors: Hidekazu Fujie, Tadashi Uchiyama, Satoshi Hanawa, Naoto Murasawa
  • Patent number: 9879598
    Abstract: A diagnosis device diagnoses a cooler adapted to cool a fluid flowing through intake and exhaust systems of an engine, and includes: a downstream temperature sensor for detecting a fluid temperature downstream of the cooler; a fluid temperature calculation unit for calculating a fluid temperature upstream of the cooler based on a fluid state quantity; a sensor output value calculation unit for assuming an upstream temperature sensor configured to detect a fluid temperature upstream of the cooler, reflecting a sensor response delay in the calculated fluid temperature, and calculating an estimated sensor output value of the upstream temperature sensor; and a cooler diagnosis unit for diagnosing the cooling efficiency of the cooler based on an actual sensor input value entered from the downstream temperature sensor and the calculated estimated sensor output value.
    Type: Grant
    Filed: July 31, 2014
    Date of Patent: January 30, 2018
    Assignee: ISUZU MOTORS LIMITED
    Inventors: Satoshi Hanawa, Tadashi Uchiyama, Hidekazu Fujie, Naoto Murasawa
  • Patent number: 9784200
    Abstract: An exhaust purification system includes: a diesel oxidation catalyst (DOC) provided on an exhaust passage of an engine; a diesel particulate filter (DPF) provided on the exhaust passage at a position downstream of the DOC to collect particulate matter contained in exhaust gas; electrodes that detect a capacitance of the DOC; a particulate matter accumulation estimating unit that estimates an amount of particulate matter accumulated in the DPF on the basis of the detected capacitance; and a forced regeneration control unit that injects fuel into the DOC and performs forced regeneration that burns and removes at least the particulate matter accumulated in the DPF when the estimated accumulated particulate matter amount surpasses a predetermined amount.
    Type: Grant
    Filed: October 8, 2014
    Date of Patent: October 10, 2017
    Assignee: ISUZU MOTORS LIMITED
    Inventors: Tadashi Uchiyama, Hidekazu Fujie, Naoto Murasawa, Satoshi Hanawa
  • Publication number: 20170226949
    Abstract: The sensor includes a filter member including cells that trap PM in exhaust gas, electrode members arranged to face each other with the cell interposed and forming a capacitor, an electric heater that executes, when an amount of PM has accumulated in the cells, filter regeneration for combusting and removing the PM, a temperature sensor that acquires the temperature of the filter member, a storage unit that stores therein a reference temperature, which is the temperature of the filter member where the filter regeneration has been executed in a state in which PM is not flowing into the filter member, and estimation units that estimate a PM amount included in the exhaust gas based on (a) an electrostatic capacitance change amount between the electrode members during a regeneration interval and (b) a difference between the temperature acquired by the temperature sensor and the reference temperature during a filter regeneration interval.
    Type: Application
    Filed: August 11, 2015
    Publication date: August 10, 2017
    Inventors: Tadashi UCHIYAMA, Naoto MURASAWA, Satoshi HANAWA
  • Publication number: 20170227423
    Abstract: The sensor includes a filter member including cells that trap PM in exhaust gas; electrode members arranged to face each other with the cell interposed and forming a capacitor, an electric heater that executes, when an amount of PM has accumulated in the cells, filter regeneration of heating the cells to combust and remove the PM, a storage unit that stores a reference reduction amount, which is an electrostatic capacitance reduction amount between the electrode members in a case where the filter regeneration is executed in a state where the PM is not flowing into the filter member, and estimation units that estimate a PM amount based on (a) an actual electrostatic capacitance change amount between the electrode members during a regeneration interval period, and (b) a difference between an actual electrostatic capacitance reduction amount between the electrode members and the reference reduction amount during a filter regeneration period.
    Type: Application
    Filed: August 11, 2015
    Publication date: August 10, 2017
    Inventors: Tadashi UCHIYAMA, Naoto MURASAWA, Satoshi HANAWA
  • Patent number: 9702293
    Abstract: A diagnostic device includes: a DOC for oxidizing hydrocarbon (HC) contained in an exhaust gas; a first sensor for detecting an exhaust gas temperature at a DOC inlet; a second sensor for detecting an exhaust gas temperature at a DOC outlet; a third sensor for detecting ambient temperature; an HC heat generation rate calculation unit which calculates, based on detection values of the first and second sensors, a difference in an exhaust gas heat quantity between upstream and downstream sides of the DOC, calculates, based on the detection values of the three sensors, a heat loss quantity released to outside air from the DOC, and adds the heat loss quantity and the exhaust gas heat quantity difference to calculate a heat generation quantity of HC in the DOC; and a DOC deterioration determination unit which determines, based on the calculated HC heat generation quantity, deterioration of the DOC.
    Type: Grant
    Filed: September 18, 2014
    Date of Patent: July 11, 2017
    Assignee: ISUZU MOTORS LIMITED
    Inventors: Hidekazu Fujie, Tadashi Uchiyama, Satoshi Hanawa, Naoto Murasawa
  • Patent number: 9695732
    Abstract: A diagnostic device for an exhaust gas purification system that has a diesel oxidation catalyst (DOC), a diesel particulate filter, and an exhaust pipe injection device. The device includes a sensor for detecting a temperature of the DOC, a first calculation unit for converting an integration time of the detected temperature between regeneration intervals into a thermal history time with respect to a predetermined set temperature, and calculating a degree of degradation of the DOC based on this thermal history time, a second calculation unit for calculating a quantity of heat generated in the DOC based on the detected temperature during a forced regeneration execution period, and calculating another degree of degradation of the DOC based on the quantity of heat generated; and a diagnosis unit for diagnosing a degradation state of the DOC based on the degrees of degradation entered from the first and second calculation units.
    Type: Grant
    Filed: October 2, 2014
    Date of Patent: July 4, 2017
    Assignee: ISUZU MOTORS LIMITED
    Inventors: Hidekazu Fujie, Kazuo Oosumi, Tadashi Uchiyama, Satoshi Hanawa, Naoto Murasawa
  • Publication number: 20170159536
    Abstract: The PM sensor includes: a filter member having a plurality of measuring cells which are defined by a porous partition wall and configured to trap particulate matters in exhaust gas; at least a pair of electrode members which are disposed to face each other with the measuring cell sandwiched therebetween to form a condenser; a heater member which heats the measuring cell to burn and remove particulate matters accumulated in the measuring cell; and an estimation unit which estimates an amount of the particulate matters contained in the exhaust gas based on an electrostatic capacity between the pair of electrode members
    Type: Application
    Filed: June 11, 2015
    Publication date: June 8, 2017
    Applicant: ISUZU MOTORS LIMITED
    Inventors: Tadashi UCHIYAMA, Naoto MURASAWA, Satoshi HANAWA
  • Patent number: 9664085
    Abstract: An exhaust purification system includes a selective catalytic reduction (SCR) catalyst disposed at an exhaust system of an engine for using ammonia that is generated from urea water as a reducing agent to reduce NOx contained in exhaust gas, a device that injects urea water to the SCR catalyst, an inlet-side electrode that detects capacitance within the SCR catalyst at least from a vicinity of an inlet of the SCR catalyst to a vicinity of an intermediate section in an exhaust gas flowing direction, an outlet-side electrode that detects the capacitance within the SCR catalyst at least from the vicinity of the intermediate section to an outlet of the SCR catalyst in the exhaust gas flowing direction, and a calculation unit that calculates an ammonia adsorption amount within the SCR catalyst on a basis of the capacitances detected from the inlet-side and the outlet-side electrodes.
    Type: Grant
    Filed: October 8, 2014
    Date of Patent: May 30, 2017
    Assignee: ISUZU MOTORS LIMITED
    Inventors: Tadashi Uchiyama, Hidekazu Fujie, Naoto Murasawa, Satoshi Hanawa
  • Publication number: 20160245141
    Abstract: An exhaust purification system includes a selective catalytic reduction (SCR) catalyst disposed at an exhaust system of an engine for using ammonia that is generated from urea water as a reducing agent to reduce NOx contained in exhaust gas, a device that injects urea water to the SCR catalyst, an inlet-side electrode that detects capacitance within the SCR catalyst at least from a vicinity of an inlet of the SCR catalyst to a vicinity of an intermediate section in an exhaust gas flowing direction, an outlet-side electrode that detects the capacitance within the SCR catalyst at least from the vicinity of the intermediate section to an outlet of the SCR catalyst in the exhaust gas flowing direction, and a calculation unit that calculates an ammonia adsorption amount within the SCR catalyst on a basis of the capacitances detected from the inlet-side and the outlet-side electrodes.
    Type: Application
    Filed: October 8, 2014
    Publication date: August 25, 2016
    Applicant: ISUZU MOTORS LIMITED
    Inventors: Tadashi UCHIYAMA, Hidekazu FUJIE, Naoto MURASAWA, Satoshi HANAWA
  • Publication number: 20160245722
    Abstract: A diagnosis device includes: a diesel particulate filter (DPF) collecting particulate matter (PM) in exhaust gas; a resistive type PM sensor provided downstream of the DPF, detecting an amount of PM from current flowing through PM deposited between electrodes. An actual regeneration interval calculator calculating an actual interval from completion of regeneration of the sensor to a start of the next regeneration; a PM slippage amount calculator estimating an amount of PM slippage in exhaust gas that slips through the DPF, assuming the DPF is normal; an estimated regeneration interval calculator calculating, on the basis of the PM slippage amount, an estimated interval from completion of the regeneration of the sensor to the start of the next regeneration; and a DPF failure-normal determination device determining whether the DPF has failed or is normal by comparing the actual interval to the estimated interval.
    Type: Application
    Filed: September 26, 2014
    Publication date: August 25, 2016
    Applicant: ISUZU MOTORS LIMITED
    Inventors: Satoshi HANAWA, Tadashi UCHIYAMA, Hidekazu FUJIE, Teruo NAKADA, Naoto MURASAWA
  • Publication number: 20160237872
    Abstract: An exhaust purification system includes: a diesel oxidation catalyst (DOC) provided on an exhaust path of an engine; an upstream diesel particulate filter (DPF) and a downstream DPF that are provided on the exhaust path at positions downstream of the DOC to collect particulate matter contained in exhaust gas; electrodes that detect a capacitance of the upstream DPF; a particulate matter accumulation estimating unit that estimates at least an amount of particulate matter accumulated in the downstream DPF on the basis of the capacitance received from the electrodes; and a forced regeneration control unit that injects fuels into the DOC and performs forced regeneration that burns and removes at least the particulate matter accumulated in the downstream DPF when the estimated amount of particulate matter from the particulate matter accumulation estimating unit surpasses a predetermined amount.
    Type: Application
    Filed: October 8, 2014
    Publication date: August 18, 2016
    Applicant: ISUZU MOTORS LIMITED
    Inventors: Tadashi UCHIYAMA, Hidekazu FUJIE, Naoto MURASAWA, Satoshi HANAWA