摘要:
To provide protection to the sensitive solid ion conductive electrolyte, a metal sleeve is placed to surround the electrolyte, with clearance, and formed with openings having an increasing cross-sectional area starting from the housing or socket towards the bottom of the solid electrolyte tube to provide an approximately even temperature gradient upon exposure of the element to exhaust gases, the sleeve being additionally so formed that deflection surfaces or vanes are formed internally thereof, for example by punching the openings through the sleeve as elongated slots leaving deflecting vanes, to deflect gases passing through the openings from direct impingement on the solid electrolyte tube to protect the solid electrolyte tube against impact and contamination.
摘要:
To improve operation and output voltage, particularly at 400.degree. C. and less, an oxygen sensor, especially adapted to determine oxygen content of automotive exhaust gases, is constructed by utilizing two electrodes applied on a body of stabilized zirconium dioxide, for example a closed tube, by making an electrode exposed to the exhaust gases in form of a mixture of finely dispersed ceramic material and a platinum-rhodium alloy, the ceramic material being present at about 40% (by volume) and 60% (by volume) platinum-rhodium alloy of 50-94% platinum and 50-6% rhodium (by weight). The second electrode, exposed to a reference gas comprises an alloy of palladium and another noble metal in a ratio of about 19-90% (by weight) Pd and 81-10% (by weight) noble metal. This electrode may also contain up to 40% (by volume) finely dispersed ceramic material. The electrode exposed to the exhaust gases is covered with a porous coating. The electrodes can be applied as aqueous or organic solutions of soluble noble metal compounds or suspensions, colloidal suspensions, with organic solvents, and the like, and subsequent sintering.
摘要:
A method of producing a spark plug for internal combustion engines comprising arranging a metal piece formed of a noble material on an end face of at least one metal electrode of the spark plug and directing laser beams onto an outer surface of the metal piece facing the spark gap to form an alloy zone between the one metal electrode and a wear-resistant layer facing the spark gap, the alloy zone consisting of materials of the metal electrode and the metal piece with the proportion of the material of the metal electrode continuously decreasing from an area abutting the metal electrode and consisting only of the metal electrode material, to an area abutting the wear-resistant layer which consists only of the material of the metal piece.
摘要:
To heat the glow plug for an internal combustion engine, a spiral band or ribbon is wound in an essentially co-planar spiral about a central bolt secured to the bottom of the glow plug, the outer terminal of the spiral being connected to a lead-in with highly positive temperature coefficient of resistance to provide for self-limiting current flow upon heating of the glow plug. All free spaces in the glow plug are filled with a highly heat-conductive insulating material, for example magnesium oxide.
摘要:
A housing of the device has a passage formed with two spaced open ends and with an inner circumferential shoulder. A tubular member of ion-conducting solid electrolyte material has a first closed-ended portion projecting from one of the open ends, and a second portion extending through the passage and being formed with an outer circumferential flange an axial end face of which faces the one open end and is supported by the shoulder. The interior of the tubular member is in communication with the ambient atmosphere, and an electron-conductive inner electrode is provided on an inner surface of the tubular member and conductively connected with an outside terminal portion. An electron-conductive outer electrode is provided on an outer surface of the tubular member and conductively connected with the housing. A compensating arrangement is provided on the housing fixed with reference thereto and engages the second portion of the tubular member in such a way as to compensate for differential coefficience of thermal expansion and contraction of the material of the housing and of the tubular member, respectively. This prevents relative movements of the housing and tubular member when such differential expansion or contraction occurs.
摘要:
A housing of the device has a passage formed with two spaced open ends and with an inner circumferential shoulder. A tubular member of ion-conducting solid electrolyte material has a first closed-ended portion projecting from one of the open ends, and a second portion extending through the passage and being formed with an outer circumferential flange an axial end face of which faces the one open end and is supported by the shoulder. The interior of the tubular member is in communication with the ambient atmosphere, and an electron-conductive inner electrode is provided on an inner surface of the tubular member and conductively connected with an outside terminal portion. An electron-conductive outer electrode is provided on an outer surface of the tubular member and conductively connected with the housing. A compensating arrangement is provided on the housing fixed with reference thereto and engages the second portion of the tubular member in such a way as to compensate for differential coefficience of thermal expansion and contraction of the material of the housing and of the tubular member, respectively. This prevents relative movements of the housing and tubular member when such differential expansion or contraction occurs.
摘要:
To prevent ingress of moisture, water, dirt, or other contamination into the interior of an exhaust gas sensor having an opening to provide for communication with ambient air to establish an oxygen reference level, a cover cap, preferably of metal, but which may be of plastic if extreme heat resistance is not required, is placed over the sensor, the cover cap being formed with a labyrinth which provides for communication between ambient air and the interior of the sensor, the labyrinth preferably being formed as a groove, especially a spiral groove, in the interior of the cap and having access to outside ambient air, the cap preferably being secured by means other than friction, such as a spot weld, an engagement catch or the like to the sensor housing.
摘要:
To provide for insulation between the conductors of a solid electrolyte ion-conductive oxygen measuring tube and a steel housing thereof, for introduction into the exhaust system of an automotive vehicle, the housing is formed with a shoulder against which a ceramic ring is seated, the tube passing through the ring, and likewise being formed with a shoulder seating against the ring. The outer conductor along the tube extends beyond the ring. A resilient electrically conductive mass such as graphite is packed around the tube, and spaced from the inner walls of the housing by a resilient mass of an insulating powder, such as talcum. The tube is held in position by a second insulating ring, the aperture of which is lined with a metallic sleeve contacting the electrically conductive powder and providing a contact connection to a terminal located in an end insulator secured to the housing; the interior of the tube is likewise connected to another terminal located in the insulator.
摘要:
A sensor (10) optically coupled to the combustion chamber (10') of an internal combustion (IC) engine is kept free from contaminating or dirt deposits, or the like, by subjecting the sensor to mechanical shocks or vibration. The mechanical shocks or vibration are obtained by the engine itself by controlling the engine to operate for a predetermined time period as set by a monostable flip-flop (FF) (18) under controlled knocking conditions, the shock waves within the combustion chamber causing flaking off or dropping off of contaminating deposits. Controlled knocking can be obtained by advancing ignition timing by additional control of an ignition system (19) in a direction of excessive spark advance, or overriding a knocking inhibiting system already present on the engine. The degree of contamination of the sensor can be determined, for example, by integrating the light received over a predetermined angle of rotation of the engine crankshaft and comparing this rotation with the amount of fuel supplied to the engine for combustion, for example by comparison with timing of a fuel injection pulse, or the like.
摘要:
To positively exclude oxygen from a heating spiral located within the interior of a glow plug, so that the heating spiral can use a material having a high positive temperature coefficient of resistance, an insulating bushing separates a central connecting bolt from the surrounding metal sleeve and at least one, and preferably both the bolt and the metal sleeve are formed with circumferential matching ridges and grooves into which the insulating bushing will be pressed to provide an effective seal and a long, tortuous path for any possible leakage of air past the seal, even under the extremes of operating conditions and temperature gradients to which glow plugs are exposed in use. To further exclude oxygen from the heating spiral, the filler material adjacent the sealing bushing can include material having a high affinity to oxygen, such as aluminum or magnesium, so that any oxygen molecules which might leak past the seal will be bound thereby.