Abstract: An apparatus is proposed for controlling the exhaust recirculation rate in an internal combustion engine, in particular an engine with auto-ignition, which includes preferably one mixture valve in the area of the discharge opening of the exhaust recirculation line and which is characterized in that the control is accomplished via the mixture valve position ahead of the inlet valves in accordance with the concentration of at least one component of the air-exhaust gas mixture and/or at least one component of the exhaust gas. Thus it is possible to operate the engine with a relatively emission-free exhaust. An exhaust gas reservoir is further provided, with which peaks in the exhaust gas concentration due to a dynamic driving mode can be intercepted. Finally, it is also proposed that the exhaust recirculation be realized solely via a pressure, which can be controlled in open-loop or closed-loop fashion, in the exhaust line by means of a valve.

Abstract: To apply a measured quantity of air to the electrodes applied to a plate-like solid electrolyte body, which may be a chip on a carrier or may, itself, form the carrier, grooves, flutes, ducts, or depressions are formed in the carrier and/or a cover plate, the grooves terminating at an edge portion with access to the gas to be supplied, and having a size such that their clear height is preferably in the lower micron region, and a width, preferably under 1 mm, and particularly between 0.2 and 0.4 mm. The higher limits are applicable to apply, for example, air to a reference electrode, to apply ambient oxygen thereto; the lower limits are appropriate when operating the sensor as a polarographic sensor, in which the diffusion limited current, upon application of a bias voltage, is an analog measure of the oxygen concentration in the gas, and the gas supply to the electrode must be suitably controlled to prevent saturation conditions.

Abstract: A method and system for controlling the temperature of a heat measuring sensor such as an oxygen sensor located in the exhaust line of an internal combustion engine so that the oxygen sensor will operate within optimal operating temperature. To accomplish this, a heating system including a control mechanism is provided for the oxygen sensor which adjusts the temperature of the oxygen sensor by controlling the output of a heater during the operation of the internal combustion engine according to characteristic engine operating conditions which have an effect on the temperature of the oxygen sensor, the most significant of which is engine load status. These conditions are sensed as a quantity by probes located so as to measure such operating conditions and send a signal to the control mechanism and its sensor heater.

Abstract: To simplify manufacture and provide a polarographic sensor of high response speed, operating according to the current limiting principle, an oxygen molecule migration barrier is provided leading to the cathode by separating the cathode from the space where the gas to be tested exists by a wall through which a hole is provided which extends therethrough to a small space immediately above the cathode defined by support elements placed immediately on the cathode. The hole, or a plurality of holes, is so dimensioned that the diameter thereof, with respect to its length, is small, with diameters of between 0.01 to 0.06 mm and a length of at least about 1 mm being suitable.

Abstract: To measure partial oxygen pressure in gases, particularly exhaust gases of automotive-type combustion engines, a solid electrolyte plate of elongated rectangular configuration has at least one electrode pair applied to a single surface thereof, which is exposed to the measuring gas. Preferably, the gap between electrodes is elongated, by forming the electrodes in comb-interdigited form. A thermocouple - temperature sensor can be applied between connecting tracks for the electrodes which extend longitudinally of the electrolyte plate towards the other end thereof, through a sealing mass holding the plate within a housing, the other end forming, simultaneously, a connection terminal for connection to an electric connector or plug. A heating element can be placed on the obverse side of the plate, preferably in the position in the gap between the electrodes.

Abstract: To facilitate mass production and permit ready introduction of a substance which provides an oxygen partial pressure reference level, for example the oxygen in ambient air, an elongated plane flat plate-like solid electrolyte body is provided with electrodes thereon, and one of the electrodes is covered by a trough-like cover element to form the reference electrode, the space beneath the trough-like element and the electrode itself being available for the substance which may, but need not be, the oxygen of air, and may be a solid material providing a reference oxygen partial pressure level. The cover plate may, itself, be made of solid electrolyte material and may form a portion of another sensing element, so that a plurality of sensing elements can be superimposed in sandwich-like fashion. A heater element can be applied to a flat plate element of the assembly where desired. The sensors can operate in the potentiometric or polarographic mode.

Abstract: To improve the response speed of an electrochemical oxygen sensor, particularly for automotive use, to sense the oxygen content in exhaust gases, and which can be operative either as a polarographic sensor (requiring application of a voltage thereto), or as a potentiometric sensor (having one catalytically active electrode and another which is less catalytically active), an elongated insulating carrier plate (29), for example of a ceramic, has layer electrodes (30, 31) applied to one major surface thereof and a layer of solid electrolyte material (32) over the electrodes, so that the electrodes will be embedded in the solid electrolyte material. The carrier plate (29) is of a material pervious to oxygen molecules. A gas-impervious insulating cover (33), for example of a ceramic glass, covers the layer of solid electrolyte material (32). A heating element (34) protected by a protective cover (35), for example of aluminum oxide, can be applied against the gas-impervious cover layer (33).

Abstract: A valve arrangement, especially for controlling flow of hot water through a heating device of a motor vehicle, mainly comprises a closed housing provided with an inlet chamber and an outlet chamber communicating with each other through an opening forming a valve seat, and a valve member movable relative to the valve seat for opening and closing the opening. The arrangement includes further a flexible membrane which is clamped at its outer periphery to the housing and which forms a control chamber at the side of the inlet chamber facing away from the valve seat. The valve member is operated by an electromagnet which acts also on an auxiliary valve member in the control chamber to create during movement of the valve member toward the valve seat a higher pressure in the control chamber than in the outlet chamber and during movement of the valve member away from the valve seat a lower pressure in the control chamber than in the inlet chamber.

Abstract: A rotary compressor includes housing means in which an impeller is rotatably mounted.

Abstract: A completely electronic circuit operating from the respective outputs of a motor speed transducer and a transmission input speed transducer and from other inputs which are usually constant voltages calculates a control signal for moving the control member of an automatic clutch for coupling a vehicle motor to a vehicle transmission during slipping engagement of the clutch until gripping engagement is made in such a way as to minimize the jolt effect without the necessity of hydraulic or mechanical damping devices.

Abstract: A rotary positive-displacement pump in which the vane or vanes separating the chambers are locked in the inner dead center point after a certain outlet pressure has been attained, in order to shut off the pump. A corresponding locking apparatus has a detent which assures that each vane is locked in a form-locking manner in the position which shuts off the pumping action. Preferably, the locking apparatus has an overstroke step by means of which it is assured that each vane is constantly held at an increased distance from its sliding surface so that friction and impact noises are positively avoided.

Abstract: Rapid movement of the gas pedal initiates a shifting operation to the next higher or next lower gear depending upon whether the speed of the gearing lies above or below a predetermined speed range. The speed range extends from a first to a second predetermined speed. Both the width of the range and the actual values of the first and second predetermined speed are automatically adjusted as a function of the throttle valve position and the then-present gear. If the gas pedal is not activated but the gear speed is less than a predetermined first threshold speed, an automatic down-shift takes place. Up-shifting can only occur when the speed of the gearing exceeds a minimum up-shift speed. Engagement and disengagement of the clutch is controlled and may include jolt limiting. The engine speed is limited during gear shifting.

Abstract: In a hydraulic transmission in which couplings and brake bands (servo-elements) control the gear ratio and are themselves engaged and disengaged in accordance with pressure applied thereto, a motor-driven slider is provided to connect a main pressure source directly to servo-elements which will remain engaged in the newly selected gear ratio. Solenoid operated valves are interposed between the main pressure source and a second intake port of the slider. Milled channels in the slider connect this second intake port to the servo-elements to be newly engaged during the gear shift. A known gear control unit operates the valves to control the rate of change of pressure increase at the second intake port to a selected value which will limit the jolt of the vehicle to a predetermined maximum jolt.

Abstract: An electrical heating element 35, 35' is located in a thin walled, closed metal tube or sleeve 37, 37' which is packed with a packing material 38, 38' of good heat conductive, insulating properties; the electrical heating element is a spirally wound resistance heater embedded in the insulating packing. A solid electrolyte body 11, 68 surrounds at least a portion of the thin walled metal sleeve and is positioned in heat exchange relation therewith. The solid electrolyte body may be a closed tube 11 or may be applied as a ring element 68 over the thin walled metal tube with an insulating material layer 66 interposed.

Abstract: An internal combustion engine is equipped with an air line for admitting supplementary air to the induction manifold or the exhaust manifold in order to compensate for an intentional air deficiency, so as to make the mixture stoichiometric. The air line is throttled by a pneumatically activated throttle valve which is subject to at least two control pressures, one of these being the atmosphere or a constant pressure and the other being, for example, the induction tube vacuum. The termini of the two lines which admit these control pressures are so disposed in the valve as to be jointly openable and closable, in opposite phase, by an electromagnetically controlled valve-closing leaf-spring. The electromagnet is energized by a current of variable frequency, the frequency being dependent on the exhaust gas composition as monitored by an oxygen sensor.

Abstract: A fuel metering system of an internal combustion engine is regulated by a data processor which has stored data prescribing the proper amount of fuel to be metered out for particular positions of the throttle valve and for particular values of the engine rpm. This preliminary adjustment is further refined by providing the data processor with feedback data concerning actual engine operating parameters, e.g. the exhaust gas composition, engine speed fluctuation and temperature. The feedback data is used by the data processor to override and further adjust the fuel quantity metered out to the engine.

Abstract: An electro-chemical sensor to determine the oxygen content of exhaust gases, particularly from internal combustion engines. The sensor contains a tubular solid electrolyte closed at one end having a catalytically active layer on the outside to be exposed to the exhaust gas. The inside of said solid electrolyte tube is exposed to the ambient air and is provided with a contact portion arranged at the bottom of said solid electrolyte tube. The sensor contains an elongated axial center electrode which is pressured against the bottom (closed end) of the inside of the tubular solid electrolyte, preferably by means of a compression spring which may be mounted internal of said center electrode or external thereof. The central electrode comprises an insulating body having a heating element in the area which will be adjacent the portion of the solid electrolyte in contact with the exhaust gases. Additionally the central electrode also carries an electric lead to said contact portion.

Abstract: A motor vehicle is equipped with a heater assembly in which hot coolant from the engine is circulated through a first heat exchanger, normally called heater. The vehicle is also equipped with a refrigerating unit, i.e., an air conditioner, which has a second heat exchanger, or cooler, located in front of or behind the heater. Two separate temperature sensors are provided. One of these senses the compartment temperature while the other is located directly adjacent to the heater and senses the temperature of the air leaving the heater. The responsivity of this latter sensor is made substantially lower than that of the compartment sensor, i.e., its signal change per unit temperature change is lower, resulting in differential weighting. A control unit is so constructed that when the compartment temperature rises, the heater, which is normally cycled on and off in a quasi-continuous fashion, is shut off. If the temperature rises further, the controller activates the refrigerator unit and the air is cooled.

Abstract: 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.

Abstract: A portion of the exhaust gas of an internal combustion engine is returned to the induction manifold through an exhaust gas recycling line. This recycle line contains one or more orifice plates to create a measurable pressure drop when gas is flowing. The gas flow through the recycle line may be interrupted in controlled manner by a valve, particularly a magnetically actuated valve. The pressure drop across the orifice plate or plates is sensed by pressure-responsive electrical switches which provide input signals for a logical circuit that energizes a signaling device to warn the operator of a malfunction in the exhaust gas recycling system.