摘要:
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.
摘要:
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. The contact portion may be attached to the central electrode.
摘要:
The linearity of response of a polarographic sensor, of the diffusion-limited current type, having a solid electrolyte (1) and being particularly adapted for measuring oxygen content in exhaust gases from combustion processes, is improved by providing the anode (2b) of the sensor's first, measuring cell with a constant, internal supply of reference oxygen. Preventing the oxygen concentration at the anode (2b) from fluctuating eliminates a non-linearity which would otherwise occur in the plot of oxygen concentration versus diffusion-limited current, as the fuel/air ratio of the mixture being combusted passes 1.The oxygen supply takes the form of a second, pumping cell (3a,3b) which can utilize the same solid electrolyte layer (1) as the first cell, and which pumps oxygen ions across the electrolyte to the second cell's anode (3b), where they become oxygen molecules and are directed through a duct (8) to the measuring cell's anode (2b).Excessive pressure in the duct (8) is prevented by providing small pores (10) in the surrounding glass cover (9) for outward diffusion of excess oxygen. A constant voltage is applied to both cells.
摘要:
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.
摘要:
A method is proposed for regulating the combustion of operating mixtures in the combustion chambers of internal combustion engines. The course of the light intensity of the light resulting from combustion in the combustion chamber is detected and evaluated over the course of combustion; reference control variables derived therefrom are formed for use by subsequently disposed closed-loop control devices of the engine.
摘要:
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. More than one such sensor element may be secured in the same housing, and, for example, two such plates, back to back, with the heating element therebetween, spaced from each other, or as a common block. The sensor may be used for potentiometric and/or polarographic measurement, depending upon cover coatings on the electrodes which control exposure thereof to the gases, catalytic or non-catalytic action of the electrodes (for example being of platinum or gold, respectively) and whether a voltage is applied across the electrode terminals, or the sensor is to operate as an electrochemical cell. Such sensor can be inexpensively made, are suitable for mass production, and flexible with respect to their mode of operation.
摘要:
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).
摘要:
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.
摘要:
The invention is directed to an arrangement for controlling an internal combustion engine equipped with glow plugs. The arrangement includes a heat-control circuit for controlling the temperature of the glow plug and an ancillary control circuit which can be a fuel control circuit for example. The ancillary control circuit takes over from the heat-control circuit for the purpose of controlling the ignition time point of the mixture when the temperature-control has reached its limit. A comparator is provided to monitor the heat-control circuit and to activate the ancillary control circuit if necessary.
摘要:
To permit individual evaluation of the combustion processes in the respective cylinders (1a-d) of an internal combustion (IC) engine (2), individual optical pick-ups (3a-d; 4a-d) are coupled to the respective cylinders, the output signals either in optical or electrical form are conducted to separate pick-ups for individual evaluation or, alternatively, the output signals are combined and then again separated out by a steering circuit. Individual evaluation can be accomplished by locating light guide fibers from the sensors in a predetermined position with respect to opto-electrical transducers; by forming scanning windows, for example by a rotating disk (19, 20) rotating n in synchronism with the engine and permitting passage of light from the respective fibers of the light guides to respective pick-ups; or by combining the light outputs from the respective sensors (4) either optically by intermixing light guide fibers in a common cable (6'), or electrically in an equivalent OR-circuit (FIG. 8: R.sub.L) with subsequent correlation of the output signal with a specific cylinder by a scanning disk (FIG. 6: 20) with suitably placed openings (22a-d) therein, or an electrical time-multiplex steering circuit (FIG. 8: 30) operating in synchronism with rotation of the engine.