Robert Boschgmbh

Leo Steinke

Helmut Weyl

Ernst Linder

Karl-Hermann Friese

Gunther Kauhl

Franz Rieger

Helmut Maurer

Walter Benedikt

Hannes Pflug

Werner Herden

Klaus D Muller

Lothar Weber

Thomas Isella

Adolf R Fritz

Rainer Corbach

Josef Tosch

Gerhard Bruggen

Hermann Fischer

Hans-Ulrich Gruber

Rainer Noack

Dietrich Schuldt

Armin Czinczel

Rudolf Jurinke

Heinz Krauss

Winfried Keiper

Wolfgang Heinemann

Wolf-Dieter Hacker

Rainer Hellberg

Jens Glauner

Herbert Lang

Gunter Knoll

Antilock control system

Optical transmitter for producing an optical signal indicative of

In a spark plug a longitudinal bore is arranged eccentrically in a housing. A housing part with a thicker wall thickness is thereby formed, and a pressure sensor is provided in a bore or this housing part, and therefore the pressure sensor is in direct connection with the combustion chamber. No structural outer changes are required on the housing, so that the spark plug can be installed without any problems in known arrangements.

Spark plug with a pressure measuring device

Method of production of a spark plug for internal combustion engines

Spark plug with a measurement device

To prevent an increase in diameter or the formation of fissures of resistance wire elements which are placed within a glow sleeve (22) of a glow element (13) during a compaction step in which a pulverized or powder-like heat conductive resistance material (26), for example magnesium oxide, is compacted within the glow element (13) to securely seat the resistance wire (24) therein, the resistance wire (24) is made of a plurality, for example two individual wire elements or strands (24/1, 24/2) twisted together, such that the pitch (27) of the twist is greater than n times the diameter of the number of wire strands twisted together, for example, for two wires, about three times the individual wire element or strand diameter.

Glow plug for diesel engines

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.

Optical engine knock sensing system

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.

Oxygen content exhaust gas sensor, and method of its manufacture

To rapidly heat glow plugs having positive temperature coefficient characteristics, or glow plugs in circuit with a positive temperature coefficient resistor, without overloading connecting relay contacts, a current limiting resistor is placed in circuit with the glow plugs upon first connection thereof to a supply source. After elapse of a first time interval of about 0.1 to 0.3, maximally 1 second, a second switch is controlled to short-circuit the current limiting resistor to permit full voltage to be applied to the glow plugs for rapid heating thereof, during a second time interval, for example between about 2 to 6 seconds, the positive temperature characteristics of the circuit self-limiting current through the resistors to thereby protect circuit switches and relay contacts.

Method of preheating an internal combustion engine of the diesel, or

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.

Glow plug construction

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.

Glow plug arrangement

To prevent damage to the heating wire of an electrically heated glow plug due to non-uniform expansion of materials within the glow plug upon heating thereof, and particularly due to excessive expansion of filler material surrounding a spiraled heating wire, the filler material is made in two sections, one being located within the spiral of the heater wire and comprising a material of a thermal conductivity of expansion approximately matching that of the heater wire, typically high-temperature annealed aluminum oxide, magnesium aluminum spinel, silicon nitride, boron nitride, silicon carbide, or the like, the outer section between the heater wire and the inner wall of the glow tube being of a material of good heat conductivity, such as magnesium oxide. In manufacture, the first material is introduced into the heater wire spiral in the form of a compacted rod which, after assembly to the tube and introduction of the second material, is crushed by diametrical reduction of the tube after closing thereof, for example by hammering, rolling or swaging.

Glow plug structure

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.

Electrochemical exhaust gas oxygen sensor construction

An RC circuit branch determines the duration of the period for which the primary circuit of a spark coil remains interrupted after the main peak of the spark discharge in the secondary circuit that includes a spark plug. Engine speed and engine temperature are used to shorten the period during which the secondary circuit is allowed to entertain a spark discharge. As engine speed increases the spark discharge period is reduced until a certain speed is reached after which the spark discharge period remains constant with further increase of engine speed. Engine temperature is also used to shorten the spark discharge period by the use of a temperature sensitive resistor. The charging and discharging of the storage capacitor of the RC circuit branch are separately controlled by the shunt circuits in which diodes are interposed and in one embodiment an additional capacitor can be switched into parallel into the RC circuit branch when the engine is starting up. The degree of intake manifold vacuum can also be used to modify the operation of the circuit.

Engine ignition system with variable spark internal duration

To avoid temperature shock and mechanical damage to oxygen sensors with ion conductive solid electrolytes exposed to the exhaust gases of internal combustion engines, a catalyst, for example in the form of aluminum oxide pellets having a catalyzing surface layer, is located to surround the oxygen sensor, or just in advance of the oxygen sensor in a bypass pipe, branching off from the exhaust gas pipe of the engine to take samples of the exhaust gases so that the sensor and catalyst form an assembly, or sensing combination. The catalyzing layer may be platinum, or a platinum metal, or an alloy of platinum with aluminum, cobalt, nickel, or chromium, or may be mineral wool, or wool of glass, or asbestos fibers having their surface coated with any of the foregoing catalysts.

Internal combustion engine exhaust gas oxygen sensor and catalyzer

Growing community of inventors

Waiblingen-Hegnach, Germany

Leo Steinke