Abstract: A particulate sensor can reduce the amount of floating ions discharged from the interior of a gas introduction pipe to the outside through a gas discharge opening, without providing an auxiliary electrode member which applies to the floating ions a repulsive force toward the gas introduction pipe to thereby assist the collection of the floating ions by the gas introduction pipe. The particulate sensor has an collection member which is connected to a gas introduction pipe to thereby be maintained at a collection potential and is disposed in the interior of the gas introduction pipe to be located between a forward end of the discharge electrode member and a gas discharge opening such that the forward end of the discharge electrode member cannot be visually recognized from the outside of the gas introduction pipe through the gas discharge opening.

Abstract: A particulate amount determination section of a particulate measurement system corrects a measurement signal or the amount of particulates determined from the measurement signal based on one or a plurality of three operating condition parameters selected from speed of the vehicle, rotational speed of the internal combustion engine and torque of the internal combustion engine.

Abstract: A particulate sensor includes: an inner metallic member which is maintained at a first potential and which has a gas introduction pipe into which a target gas is introduced; a tubular outer metallic member which surrounds the radially outer circumference of the inner metallic member and which is attached to a gas flow pipe to thereby be maintained at a ground potential; and an insulating spacer which is interposed between the inner metallic member and the outer metallic member so as to electrically insulate them from each other and which has a tubular gas contact portion which is exposed to the interior of the gas flow pipe and comes into contact with the gas under measurement. The insulating spacer has a heater for heating the gas contact portion. The heater includes a heat generation resistor embedded in the insulating spacer.

Abstract: A particulate measurement system includes an ion generation section for generating ions by means of corona discharge; an electrification chamber for electrifying particulates contained in a gas under measurement; a measurement signal generation circuit for generating a measurement signal which correlates with the amount of the particulates; and a particulate amount determination section for determining the amount of the particulates. The particulate measurement system further includes a particle diameter estimation section for estimating the particle diameter of the particulates contained in the gas under measurement. The particulate amount determination section performs correction by multiplying the measurement signal or the amount of the particulates determined from the measurement signal by a coefficient relating to the ratio between the estimated particle diameter and a reference particle diameter.

Abstract: A particle detection system includes a sensor main body having an electrification section for electrifying particles contained in a gas under measurement so as to produce electrified particles, and detects the particles contained in the gas under measurement by using the electrified particles. The sensor main body has a heater portion which generates heat upon energization so as to heat at least a portion of the electrification section. The particle detection system detects a burnable period (for example, fuel cut period) during which the gas under measurement contains oxygen for burning particles adhering to the electrification section, and energizes the heater portion during the burnable period so as to heat at least a portion of the electrification section to a temperature at which the adhering particles burn.

Abstract: A particulate sensor (1) includes an ion source (15) and a reference potential member (45). The particulate sensor (1) detects particulates S contained in a gas under measurement EG by means of ions CP. The ion source (15) includes a ceramic structure (100) having a ceramic laminate (101) and a discharge electrode member (110). The discharge electrode member (110) has an inter-layer portion (112A, 111) embedded between the layers of the ceramic laminate (101) and an exposed portion (112B) extending from the inter-layer portion (112A, 111) to a position outside the ceramic laminate (101). The discharge electrode member (110) generates the gaseous discharge between the reference potential member (45) and the exposed portion (112B) including one or more needle-shaped distal end portions (1125) upon application of a constant DC discharge potential PV2.

Abstract: A particulate sensor (1) which detects particulates S contained in a gas under measurement (EG) flowing within a gas flow pipe (EP) has a space forming portion (12) and an ion source (15). The space forming portion (12) projects into the gas flow pipe EP and forms an internal space MX. The space forming portion (12) has an introduction port (43I) and a discharge port (48O) for discharging from the internal space MX the gas EGI introduced through the introduction port (43I). The source (15) produces ions CP by gaseous discharge. The space forming portion (12) is configured such that the introduced gas EGI is discharged from the internal space MX through the discharge port (48O), the gas under measurement EG is introduced into the internal space MX through the introduction port (43I), and the introduced gas EGI is mixed with the ions CP produced by the ion source (15).

Abstract: A particulate sensor can reduce the amount of floating ions discharged from the interior of a gas introduction pipe to the outside through a gas discharge opening, without providing an auxiliary electrode member which applies to the floating ions a repulsive force toward the gas introduction pipe to thereby assist the collection of the floating ions by the gas introduction pipe. The particulate sensor has an collection member which is connected to a gas introduction pipe to thereby be maintained at a collection potential and is disposed in the interior of the gas introduction pipe to be located between a forward end of the discharge electrode member and a gas discharge opening such that the forward end of the discharge electrode member cannot be visually recognized from the outside of the gas introduction pipe through the gas discharge opening.

Abstract: A particulate sensor (10, 310) includes a flow channel forming body (25, 60, 65, 360, 365) forming a sensor internal flow channel SGW through which a gas under measurement EGI flows. The particulate sensor electrifies particulates S contained in the gas under measurement flowing through the sensor internal flow channel and detects the particulates S. The flow channel forming body (25, 60, 65) includes an inner metal tube (60, 360) and an outer metal tube (65, 365) surrounding the inner metal tube (60) from a radially outward side GDO. A tubular inter-tube gap IW between the inner metal tube and the outer metal tube forms at least a portion of the sensor internal flow channel SGW. The particulate sensor includes a heater member (100) for heating at least one of the inner metal tube and the outer metal tube.

Abstract: A particulate detection system (1) for detecting the amount of particulates S in a gas under measurement EG includes a detection section (10), a drive circuit (210, 240), and a drive control section (225). The detection section includes a first potential member (31, 12, 13) maintained at a first potential PV1, a second potential member (14, 51, 53) maintained at a second potential PVE, PV3, and an insulating member (121, 77, 76) disposed between the first and second potential members. The system includes insulation test means (215, S3, 245, S5) for testing the degree of insulation between the first and second potential members. The drive control section includes drive permission/prohibition determination means S4, S6 for determining, on the basis of the degree of insulation tested by the insulation test means, whether to permit the drive of the detection section by the drive circuit.

Abstract: A particulate sensor includes: an inner metallic member which is maintained at a first potential and which has a gas introduction pipe into which a target gas is introduced; a tubular outer metallic member which surrounds the radially outer circumference of the inner metallic member and which is attached to a gas flow pipe to thereby be maintained at a ground potential; and an insulating spacer which is interposed between the inner metallic member and the outer metallic member so as to electrically insulate them from each other and which has a tubular gas contact portion which is exposed to the interior of the gas flow pipe and comes into contact with the gas under measurement. The insulating spacer has a heater for heating the gas contact portion. The heater includes a heat generation resistor embedded in the insulating spacer.

Abstract: A particulate sensor including a sensor unit (300) having an ion generation section (611, 361, 322); an electric charge section (612) for electrically charging at least portion of particulates S using ions PI; a capture section (616, 617, 316, 326, 362) for trapping at least portion of the ions PI not used for electrically charging the particulates S; and a sensor ground section (340, 310v, 330v3) connected to the capture section and having a first floating potential corresponding to the amount of the ions PI trapped by the capture section. The sensor unit can detect the amount of the particulates S in the gas on the basis of the electric potential of the sensor ground section. The sensor ground section is covered with insulating ceramic at that outer portion of the sensor unit which comes into contact with the gas.

Abstract: A particulate detection system (1) includes detection section (10), compressed air source (300) which includes compressor (301) for producing compressed air AK, compressor drive circuit (320) and control means (100). The detection section includes a gas jetting source (11). A drive condition for jetting air AR from jetting hole (31N) at a first flow rate Q1 is defined as a first drive condition JK1, and a drive condition for jetting the air AR at a second flow rate Q2 smaller than the first flow rate Q1 is defined as a second drive condition JK2. The control means includes first instruction means S5 for driving the compressor under the first drive condition JK1 when the quantity of the particulates S is detected, and second instruction means S6 for driving the compressor under the second drive condition JK2 when the quantity of the particulates S is not detected.

Abstract: A thin plate member which has a groove portion recessed toward the inside in a radial direction with a gap interposed between the thin plate member and the outer surface of a site on the front end side of a main body section. At least one end of the thin plate member is joined to the outer surface of the main body section and is provided radially outside the site on the front end side of the main body section. A seal member is disposed in the groove portion and has elasticity due to resin. Since the gap functions as a heat-insulating layer and is interposed between the seal member and the main body section, heat conduction from the main body section, that is, heat conduction through a first pathway is reduced, and thus deterioration of the seal member due to heat is suppressed.

Abstract: A particulate measurement system includes an ion generation section for generating ions by means of corona discharge; an electrification chamber for electrifying particulates contained in a gas under measurement; a measurement signal generation circuit for generating a measurement signal which correlates with the amount of the particulates; and a particulate amount determination section for determining the amount of the particulates. The particulate measurement system further includes a particle diameter estimation section for estimating the particle diameter of the particulates contained in the gas under measurement. The particulate amount determination section performs correction by multiplying the measurement signal or the amount of the particulates determined from the measurement signal by a coefficient relating to the ratio between the estimated particle diameter and a reference particle diameter.

Abstract: A particle detection system includes a sensor main body having an electrification section for electrifying particles contained in a gas under measurement so as to produce electrified particles, and detects the particles contained in the gas under measurement by using the electrified particles. The sensor main body has a heater portion which generates heat upon energization so as to heat at least a portion of the electrification section. The particle detection system includes period detection means for detecting a burnable period (for example, fuel cut period) during which the gas under measurement contains oxygen for burning particles adhering to the electrification section, and heater energization control means for energizing the heater portion during the burnable period so as to heat at least a portion of the electrification section to a temperature at which the adhering particles burn.

Abstract: A sensor control apparatus includes a detection section and a computation section. The detection section detects an output signal output from a sensor element and changing in accordance with oxygen concentration. The computation section obtains, as correction information used for calculation of a correction coefficient, the output signal obtained in a period during which recirculation of exhaust gas into an intake atmosphere by an exhaust gas recirculation apparatus is stopped and an idle stop operation of an internal combustion engine is being performed.

Abstract: A particulate detection system (1) includes detection section (10), compressed air source (300) which includes compressor (301) for producing compressed air AK, compressor drive circuit (320) and control means (100). The detection section includes a gas jetting source (11). A drive condition for jetting air AR from jetting hole (31N) at a first flow rate Q1 is defined as a first drive condition JK1, and a drive condition for jetting the air AR at a second flow rate Q2 smaller than the first flow rate Q1 is defined as a second drive condition JK2. The control means includes first instruction means S5 for driving the compressor under the first drive condition JK1 when the quantity of the particulates S is detected, and second instruction means S6 for driving the compressor under the second drive condition JK2 when the quantity of the particulates S is not detected.

Abstract: A particulate sensor (1) which detects particulates S contained in a gas under measurement (EG) flowing within a gas flow pipe (EP) has a space forming portion (12) and an ion source (15). The space forming portion (12) projects into the gas flow pipe EP and forms an internal space MX. The space forming portion (12) has an introduction port (43I) and a discharge port (48O) for discharging from the internal space MX the gas EGI introduced through the introduction port (43I). The source (15) produces ions CP by gaseous discharge. The space forming portion (12) is configured such that the introduced gas EGI is discharged from the internal space MX through the discharge port (48O), the gas under measurement EG is introduced into the internal space MX through the introduction port (43I), and the introduced gas EGI is mixed with the ions CP produced by the ion source (15).

Abstract: A particulate sensor (1) includes an ion source (15) and a reference potential member (45). The particulate sensor (1) detects particulates S contained in a gas under measurement EG by means of ions CP. The ion source (15) includes a ceramic structure (100) having a ceramic laminate (101) and a discharge electrode member (110). The discharge electrode member (110) has an inter-layer portion (112A, 111) embedded between the layers of the ceramic laminate (101) and an exposed portion (112B) extending from the inter-layer portion (112A, 111) to a position outside the ceramic laminate (101). The discharge electrode member (110) generates the gaseous discharge between the reference potential member (45) and the exposed portion (112B) including one or more needle-shaped distal end portions (1125) upon application of a constant DC discharge potential PV2.