Abstract: A terminal includes a spine extending along a longitudinal axis from a first end to a second end and extending along a lateral axis, which is perpendicular to the longitudinal axis, from a first edge to a second edge. An attachment portion at the first end provides fixation to an electrical conductor. A contact portion extends from the second end and cantilevers over the spine such that the contact portion is spaced apart from the spine in a direction along a vertical axis which is perpendicular to both the longitudinal axis and the lateral axis. A locking tab extends from the first edge and has a locking tab attachment end which is fixed to first edge and which extends toward, and is aligned with, the contact portion in a direction parallel to the vertical axis. The locking tab also has a free end which flares outward beyond contact portion.

Abstract: An exhaust sensor includes a sensing element with a ceramic sensing element substrate and a sensing element terminal which is electrically conductive and which is supported by the ceramic sensing element substrate such that the sensing element is configured to sense constituents of exhaust gases when exposed thereto. The exhaust sensor also includes a mating terminal which is electrically conductive and which is in electrical communication with the sensing element terminal. The mating terminal has a base material and a clad material bonded to the base material such that the clad material contacts the sensing element terminal and such that the clad material is located between the sensing element terminal and the base material, thereby providing the electrical communication. The clad material is an alloy which is less than or equal to 20% iron, greater than or equal to 40% nickel, and greater than or equal to 13% chromium.

Abstract: A particulate matter sensor includes a shield through which exhaust gases flow in a direction of flow from upstream to downstream. A sensing element with a positive electrode and a negative electrode separated from the positive electrode by an electrode gap is located within the shield. The positive electrode includes a plurality of positive electrode branches each having positive electrode extensions extending downstream and separated from each other by positive electrode slots. A positive electrode extension tip for each has a positive electrode extension tip width. The negative electrode includes negative electrode branches each having negative electrode extensions extending upstream which are each flanked on each side thereof by a plurality of negative electrode slots. A negative electrode extension tip for each has a negative electrode extension tip width. A sum of the positive electrode extension tip widths is greater than a sum of the negative electrode extension tip widths.

Abstract: A terminal includes a spine extending along a longitudinal axis from a first end to a second end and extending along a lateral axis, which is perpendicular to the longitudinal axis, from a first edge to a second edge. An attachment portion at the first end provides fixation to an electrical conductor. A contact portion extends from the second end and cantilevers over the spine such that the contact portion is spaced apart from the spine in a direction along a vertical axis which is perpendicular to both the longitudinal axis and the lateral axis. A locking tab extends from the first edge and has a locking tab attachment end which is fixed to first edge and which extends toward, and is aligned with, the contact portion in a direction parallel to the vertical axis. The locking tab also has a free end which flares outward beyond contact portion.

Abstract: A particulate matter sensor includes a sensing element with a first electrode and a second electrode, an inner shield with the sensing element disposed therein, and an outer shield with the inner shield disposed therein. The inner shield includes a first portion with an inner shield inlet and a second portion which is smaller in diameter that the first portion such that the first and second electrodes are within the second portion. The outer shield includes an outer shield inlet which communicates exhaust gases to the inner shield inlet.

Abstract: A particulate matter sensor includes a shield through which exhaust gases flow in a direction of flow from upstream to downstream. A sensing element with a positive electrode and a negative electrode separated from the positive electrode by an electrode gap is located within the shield. The positive electrode includes a plurality of positive electrode branches each having positive electrode extensions extending downstream and separated from each other by positive electrode slots. A positive electrode extension tip for each has a positive electrode extension tip width. The negative electrode includes negative electrode branches each having negative electrode extensions extending upstream which are each flanked on each side thereof by a plurality of negative electrode slots. A negative electrode extension tip for each has a negative electrode extension tip width. A sum of the positive electrode extension tip widths is greater than a sum of the negative electrode extension tip widths.

Abstract: An exhaust sensor includes a sensing element with a ceramic sensing element substrate and a sensing element terminal which is electrically conductive and which is supported by the ceramic sensing element substrate such that the sensing element is configured to sense constituents of exhaust gases when exposed thereto. The exhaust sensor also includes a mating terminal which is electrically conductive and which is in electrical communication with the sensing element terminal. The mating terminal has a base material and a clad material bonded to the base material such that the clad material contacts the sensing element terminal and such that the clad material is located between the sensing element terminal and the base material, thereby providing the electrical communication. The clad material is an alloy which is less than or equal to 20% iron, greater than or equal to 40% nickel, and greater than or equal to 13% chromium.

Abstract: A particulate matter sensor includes a sensing element with a first electrode and a second electrode, an inner shield with the sensing element disposed therein, and an outer shield with the inner shield disposed therein. The inner shield includes a first portion with an inner shield inlet and a second portion which is smaller in diameter that the first portion such that the first and second electrodes are within the second portion. The outer shield includes an outer shield inlet which communicates exhaust gases to the inner shield inlet.

Abstract: A method for determining the temperature of a sensor that comprises a heater is provided. The method includes the steps of applying a voltage to the heater and measuring the voltage applied to the heater and the current through the heater during a first time interval, and removing the applied voltage from the heater and leaving the heater unpowered for a second time interval. The method further includes the steps of calculating the resistance of the heater using the measured voltage and current, and determining the temperature of the sensor from the resistance using a predetermined relationship. The first time interval is selected to be sufficiently short in duration and the second time interval is selected to be sufficiently long so as to not significantly raise the temperature of the heater. The sensor temperature so determined can be used to perform diagnostic functions for a system that includes the sensor.

Abstract: An electrical connector assembly having a connector body and a conductive terminal disposed within a cavity in the connector body. The terminal is held within the cavity by a rigid stop tab and a flexible lock tab that engage the ends of the connector body. A flexible bias tab having a fixed end attached to the body of the terminal and a free end extending outward laterally from the body of the terminal is configured to engage an inner wall of the cavity and urge the body of the terminal into contact with an opposite inner wall of the cavity, thereby inhibiting lateral movement of the terminal within the cavity. The bias tab may further limit rotational movement of the terminal within the cavity. The bias tab and/or any other feature of the terminal do not engage a locking feature located within the cavity.

Abstract: A particulate matter sensor includes first and second electrodes spaced from each other with a bias resistor connected between the first and second electrodes. The particulate matter sensor allows an open circuit fault condition in the sensor or in the connectors or wiring to the sensor to be detected. A sensing system using the particulate matter sensor and a method for diagnosing faults in a sensing system are also provided.

Abstract: A diagnostic method and system is described for diagnosing an operating condition of a conductive particulate matter sensor. The sensor has a substrate with electrical resistance that varies with temperature and two electrodes on the substrate adapted to collect particulate matter between the electrodes, thereby establishing an electrically conductive path through collected particulate matter between the electrodes that can be detected by measuring electrical resistance between the electrodes, Relect. The diagnosis is performed by heating the substrate in the area between the electrodes and using the resistance between the electrodes to determine detecting whether contamination is present on the surface of the sensor. Heat may be maintained on the sensor to attempt to burn off a detected contaminant, and a subsequent resistance reading may be used to determine if the contaminant was successfully burned off.

Abstract: A method of detecting particulate matter on a particulate matter sensor includes the steps of measuring an electrical characteristic associated with the sensor, determining a value corresponding to the impedance across the sensor, and compensating the impedance for the temperature at which it was determined. The method further includes determining an estimate of the total amount of particulate matter accumulated while limiting the effects of large particles captured on the sensor or blown off the sensor. The information produced by the method may be used to provide diagnostic information regarding a particulate control system.

Abstract: A method for determining the temperature of a sensor that comprises a heater is provided. The method includes the steps of applying a voltage to the heater and measuring the voltage applied to the heater and the current through the heater during a first time interval, and removing the applied voltage from the heater and leaving the heater unpowered for a second time interval. The method further includes the steps of calculating the resistance of the heater using the measured voltage and current, and determining the temperature of the sensor from the resistance using a predetermined relationship. The first time interval is selected to be sufficiently short in duration and the second time interval is selected to be sufficiently long so as to not significantly raise the temperature of the heater. The sensor temperature so determined can be used to perform diagnostic functions for a system that includes the sensor.

Abstract: A diagnostic method and system is described for diagnosing an operating condition of a conductive particulate matter sensor. The sensor has a substrate with electrical resistance that varies with temperature and two electrodes on the substrate adapted to collect particulate matter between the electrodes, thereby establishing an electrically conductive path through collected particulate matter between the electrodes that can be detected by measuring electrical resistance between the electrodes, Relect. The diagnosis is performed by heating the substrate in the area between the electrodes and using the resistance between the electrodes to determine detecting whether contamination is present on the surface of the sensor. Heat may be maintained on the sensor to attempt to burn off a detected contaminant, and a subsequent resistance reading may be used to determine if the contaminant was successfully burned off.

Abstract: A method and system is described for removing contamination from a conductive particulate matter sensor. The sensor has a substrate with two electrodes on the substrate configured to collect particulate matter between the electrodes, thereby establishing an electrically conductive path through collected particulate matter between the electrodes that can be detected by measuring electrical resistance between the electrodes. The method includes heating the sensor to a first temperature for a first duration of time, wherein the first temperature and first time are sufficient to remove collected particulate matter from the sensor. The method further includes heating the sensor to a second temperature for a second duration of time, wherein the second temperature is higher than the first temperature, to remove contaminants that cannot be removed by heating to the first temperature for the first duration of time.

Abstract: A method of detecting particulate matter on a particulate matter sensor includes the steps of measuring an electrical characteristic associated with the sensor, determining a value corresponding to the impedance across the sensor, and compensating the impedance for the temperature at which it was determined. The method further includes determining an estimate of the total amount of particulate matter accumulated while limiting the effects of large particles captured on the sensor or blown off the sensor. The information produced by the method may be used to provide diagnostic information regarding a particulate control system.

Abstract: A particulate matter sensor includes first and second electrodes spaced from each other with a bias resistor connected between the first and second electrodes. The particulate matter sensor allows an open circuit fault condition in the sensor or in the connectors or wiring to the sensor to be detected. A sensing system using the particulate matter sensor and a method for diagnosing faults in a sensing system are also provided.

Abstract: A method of manufacturing an exhaust temperature sensor is disclosed. It includes forming a green ceramic substrate; and printing an electrical circuit on the green ceramic substrate. The method then contemplates trimming the electrical circuit to a predetermined resistance prior to firing the green ceramic. Finally, the method contemplates firing the green ceramic substrate with the electrical circuit thereon.

Abstract: A method of manufacturing an exhaust temperature sensor is disclosed. It includes forming a green ceramic substrate; and printing an electrical circuit on the green ceramic substrate. The method then contemplates trimming the electrical circuit to a predetermined resistance prior to firing the green ceramic. Finally, the method contemplates firing the green ceramic substrate with the electrical circuit thereon.