Denso Corporation

Denso Corpora Tion

Hirokatsu Imagawa

Kazuhiko Koike

Masayuki Tamura

Go Miyagawa

Masahiro Yamamoto

Takao Mishima

Kouji Andoh

Hironori Niwa

Hideki Yamada

An exhaust gas purification filter includes a plurality of cells each extending from an inflow end face to an outflow end face, a porous partition wall forming the cells in a partitioned manner, inflow-side sealing parts sealing openings on an inflow end face side of outflow cells where the exhaust gas flows out, and outflow-side sealing parts sealing openings on an outflow end face side of inflow cells where the exhaust gas flows in. Each of the inflow-side sealing parts has a porosity of less than 60%. The partition wall has a porosity of 60% or more and 70% or less. Assuming a pore size, at which cumulative pore volume is 50% in pore size distribution of the inflow-side sealing parts, is d50, and a pore size, at which cumulative pore volume is 50% in pore size distribution of the partition wall, is d50, the pore size d50is less than 18 μm, and the pore size d50is 18 μm or more and 25 μm or less.

Exhaust gas purification filter

In an exhaust gas purification filter, a partition wall has communicating pores. Each communicating pore has a surface opening on the gas-inflow-side surface and a plurality of portions, each portion having a diameter being reduced and then increased from the surface opening, one of the portions, whose diameter is the smallest, being defined as an inlet neck portion. As viewed in cross section in a thickness direction of the partition wall, the surface opening of each communication pore has a diameter defined as a surface opening diameter, the inlet neck portion of each communication pore has a diameter defined as an inlet neck diameter. The inlet neck diameter is smaller than the surface opening diameter, and an average value of the inlet neck diameters is 15 &#x3bc;m or less. A surface opening ratio of the communicating pores in plan view of the gas-inflow-side partition wall surface is 40% or more.

A method of manufacturing a particulate matter detection element for detecting particulate matter in a gas to be measured includes manufacturing flat-shaped conductor layers, flat-shaped insulating layers, a laminated structure in which the conductor layers and the insulating layers are alternately laminated, and a detecting unit having the conductor layers of different polarities as a pair of detection electrodes on a cross section of the laminated structure. The conductor layers each have a constant thickness, and include conductor layer planar portions having a stripped-pattern cross section, and tapered conductor layer end edge portions each having a triangular cross section, provided on both sides of the respective conductor layer planar portions.

Method of manufacturing particulate matter detection element

A honeycomb structural body includes: a porous cell wall that partitions a cylindrical casing; and a large number of cells extending in the axial direction X thereof and alternately blocked at an upstream end face. The large number of cells include plugged cells having plugs and penetrating cells that do not have the plugs. The plugged cells and the penetrating cells both include complete cells and incomplete cells. At least some of plugged incomplete cells of the incomplete cells have a cross-sectional area smaller than a cross-sectional area of penetrating complete cells, and are configured as blocked cells that are entirely blocked inside in the axial direction.

Honeycomb structural body, method for manufacturing the same, and exhaust gas purification filter

A particulate matter detection sensor includes a particulate matter detection unit for changing the output of an electrical signal in accordance with change in the electrical characteristics due to the deposition of particulate matter contained in an exhaust gas G discharged from an internal combustion engine, and a cover member having a cylindrical cover wall and disposed to surround the particulate matter detection unit. The particulate matter detection unit includes a deposition portion on which a part of the particulate matter is deposited, and a plurality of detection electrodes disposed being spaced apart from each other on the deposition portion. The deposition portion of the particulate matter detection unit is arranged so as to be oriented towards the tip side of the cover member. The cover wall of the cover member includes a plurality of exhaust gas introduction holes formed at positions closer to the tip side than is the deposition portion.

Particulate matter detection sensor

A particulate matter sensor and a particulate matter sensing system using such a sensor are provided which are capable of being produced at decreased cost and accurately measuring the temperature of a heater. The particulate matter sensor includes a deposition portion on which particulate matter contained in exhaust gas is accumulated, a pair of electrodes which are disposed on the deposition portion and separate from each other, a heater which heats the deposition portion, and a pair of heater leads which form a path through which electrical current is delivered to the heater. A sensing line is connected to at least one of the heater leads to measure a resistance of the heater lead.

Particulate matter sensor and particulate matter sensing system

A particulate matter detection element for detecting particulate matter in a gas to be measured includes flat-shaped conductor layers, flat-shaped insulating layers, a laminated structure in which the conductor layers and the insulating layers are alternately laminated, and a detecting unit having the conductor layers of different polarities as a pair of detection electrodes on a cross section of the laminated structure. The conductor layers each have a constant thickness, and include conductor layer planar portions having a stripped-pattern cross section, and tapered conductor layer end edge portions each having a triangular cross section, provided on both sides of the respective conductor layer planar portions.

Particulate matter detection element, particulate matter detection sensor, and method of manufacturing particulate matter detection element

A particulate matter detection apparatus includes a particulate matter quantity detection means, a temperature detection means that detects the temperature of exhaust gas, a control unit and a heating means. The particulate matter quantity detection means includes a particulate matter deposition portion that deposits thereon part of particulate matter contained in the exhaust gas emitted from an internal combustion engine and a pair of opposite electrodes arranged apart from each other on the particulate matter deposition portion. The control unit determines a deposition quantity of the particulate matter on the particulate matter deposition portion based on an electrical signal outputted by the particulate matter quantity detection means and receives information on the temperature of the exhaust gas detected by the temperature detection means. The control unit controls the heating means to heat the particulate matter deposition portion to 300&#xb0; C.-800&#xb0; C. during a cold start of the internal combustion engine.

Particulate matter detection apparatus

In a gas sensor element, a measurement gas is introduced to a measurement electrode through a porous diffusion-resistant layer. A catalyst layer is formed on an outer surface of the diffusion-resistant layer via which the measurement gas flows into the diffusion-resistant layer. In the catalyst layer, the percentage content of Pt is in the range of 2.5 to 12 mass %, the percentage content of Pd is in the range of 0.4 to 2 mass %, and the percentage content of Rh is in the range of 0.06 to 1.5 mass %. The catalyst layer includes catalytic noble metal particles each of which is made of an alloy that contains at least Pt. For each of the catalytic noble metal particles, the percentage content of Pt at an outer peripheral portion of the catalytic noble metal particle is lower than that at a core portion of the catalytic noble metal particle.

Growing community of inventors

Kariya, Japan

Hirokatsu Imagawa