摘要:
A gas sensor has improved electrical properties. In the top view of the layer planes of the body of the sensor, printed circuit traces for electrodes are arranged outside of cavities in the body, e.g., outside of the reference air duct. Furthermore, the electrodes are enlarged in the direction of the exhaust-side end of the sensor. Also, the printed circuit traces have an increased layer thickness or are formed as a double layer.
摘要:
A connection between electrically conducting layers (11, 14, 21) extending in at least two layer levels is proposed, between which at least one ceramic foil (10) is arranged. The ceramic foil has a connection (13) from the one layer level to the other layer level. A contact point (23) is provided in at least one layer level which is located outside of the connection (13) and which is formed by at least one pressure contact (10, 20) formed on an electrically conducting layer (14, 21) during lamination.
摘要:
A sensor element for a sensor for determining the concentration of a gas component in a gas mixture, in particular the oxygen concentration in the exhaust gas of internal combustion engines, has two electrodes which, together with a solid electrolyte, form a pump cell, and one of these electrodes is exposed to the gas mixture via a porous protective layer. The sensor element also has a reference electrode which is situated on the solid electrolyte and is exposed to a reference gas. One of the two electrodes, with a reference electrode and the solid electrolyte, forms a concentration cell or a Nernst cell. To make the measured values produced by the sensor element insensitive to pressure fluctuations in the gas mixture, the electrode surface of the second electrode facing away from the solid electrolyte is coated with a finely porous diffusion layer, which is directly exposed to the gas mixture, and the second electrode is used as the reference electrode of the Nernst cell. It is also provided that the porous protective layer may be configured as a coarsely porous diffusion layer, and either of the two electrodes may be used as a reference electrode of the Nernst cell.
摘要:
An electrochemical sensor measures a gas concentration of a measured gas with an electrochemical element. The electrochemical sensor includes an electrochemical pump cell with a first solid electrolyte body, a first and a second electrode, and a gas chamber, which is connected to a measured gas chamber via a gas inlet opening and in which one of the two electrodes is located. The electrochemical sensor also includes a second solid electrolyte body with an electrochemical sensor cell (e.g., a Nernst cell), which has a third electrode and a reference gas chamber in which a fourth electrode is located, with the electrodes having a supply conductor for electrical contacting. A supply conductor of the fourth electrode is provided with an electrically insulating layer to insulate it against the second solid electrolyte body.
摘要:
A probe is described for determining an oxygen concentration in a gas mixture, in particular in the exhaust gas of internal combustion engines, having a Nernst measuring cell, which has a first electrode (Nernst electrode) which is exposed to the gas mixture to be measured via a diffusion barrier, a second electrode (reference electrode) which is exposed to a reference gas, and a solid electrolyte body arranged between the first and the second electrode, and having a pump cell, which has a first electrode (inner pump electrode) which is exposed to the gas mixture via the diffusion barrier, a second electrode (outer pump electrode) which is exposed to the gas mixture, and a solid electrolyte body arranged between the first and the second electrode. The Nernst electrode and the inner pump electrode are connected at least in some sections via a joint supply conductor to a circuit arrangement for controlling and evaluating the probe. A joint supply conductor resistor of the Nernst electrode and of the inner pump electrode is formed by a loaded voltage divider whose individual resistors are arranged so that the negative feedback of a Nernst voltage circuit and of a pump voltage circuit is optimized, in particular maximized.
摘要:
An electrochemical sensor for ascertaining a gas concentration of a measuring gas includes an electrochemical element, including a first solid electrolyte body having an electrochemical pump cell and a first and a second electrode, and having a gas compartment which is connected via a gas access opening to the measuring-gas compartment, and in which one of the two electrodes is arranged. The electrochemical element further includes a second solid electrolyte body having an electrochemical sensor cell (Nernst cell) and a third and a fourth electrode. The surface of the first solid electrolyte body faces the measuring-gas compartment, and the gas access opening is covered by a porous protective layer. The electrochemical sensor includes a layer that exhibits a higher density or a lower porosity compared to the protective layer and that is allocated to the porous protective layer.
摘要:
A gas sensor is described for detecting a physical property of a measuring gas, including detecting the oxygen concentration in the measuring gas. The gas sensor includes a sensor element having a diffusion barrier, which is arranged between a first solid electrolyte layer and a second solid electrolyte layer. The diffusion barrier has a necked-down portion, i.e., a concave profile, between the first and the second solid electrolyte layer. Accordingly, a first area, which the diffusion barrier occupies in a plane which lies between the side of the first solid electrolyte layer (facing the diffusion barrier) and the side of the second solid electrolyte layer (facing the diffusion barrier), is smaller than a second area on which the diffusion barrier covers the first or the second solid electrolyte. In order to manufacture the sensor element, a first layer made of a paste containing a pore-forming material is applied onto a blank foil, and after that, a second layer made of a paste containing a pore-forming material is applied.
摘要:
An electrochemical sensor determining a gas concentration of the measuring gas. The sensor has an electrochemical element including a first solid electrolyte body having an electrochemical pump cell and a first (external pump) and a second (internal pump) electrode and having a gas chamber which is connected to the measuring gas chamber via a gas supply opening and in which the second electrode is arranged. The electrochemical element also includes a second solid electrolyte body having an electrochemical sensor cell (e.g., a Nernst cell) and a third and fourth electrode, each electrode having a lead for the electrical contacting. The leads of the first and second electrodes are decoupled capacitively from the lead of at least the fourth electrode by a device.
摘要:
A sensor for determining at least one of gas constituents and gas concentrations in a gas mixture, such as CO, NO.sub.x and HC, in exhaust gas from an internal combustion engine, includes a semiconductor gas sensor having a gas sensitive region in communication with the gas mixture; a pumping cell including a solid electrolyte carrier and pumping electrodes disposed on the solid electrolyte carrier, the pumping cell being positioned in communication with the semiconductor gas sensor for effecting oxygen transfer to the semiconductor gas sensor on the side thereof opposite the gas mixture by pumping oxygen thereto to provide an O.sub.2 mole current density in the gas sensitive region, and the pumping cell having a pumping current; a cover layer which is gas tight and which has a restricted opening defined therein provided on the pumping cell on the side thereof which communicates with the semiconductor gas sensor so that the oxygen is pumped through the restricted opening to the semiconductor gas sensor, whereby the O.sub.2 mole current density in the gas sensitive region can be increased within the restricted opening while the pumping current remains constant, the gas sensitive region of the semiconductor gas sensor being disposed in the restricted opening so that an oxygen excess is established at the gas sensitive region due to the O.sub.2 mole current density.
摘要:
In order to provide a method and arrangement for analytical determination of the relative amounts of exhaust gas components, except for water, but including hydrogen in the rich range or oxygen in the lean range, and for determining a &lgr; value, in which the exhaust gas sample can be taken at any arbitrary location, an arrangement is provided in which at least one portion of the exhaust gas is passed through a catalytic reactor (2, 22), a condenser (3,23) connected to the catalytic reactor to receive the gas passed through it, and, after passing through the condenser, the gas passes through an IR spectrometer and by a &lgr;-sensor. The oxidizable and reducible components of the exhaust gas are reacted with each other in the catalytic reactor which is heated to temperatures greater than 450° C. The relative amounts of CO2, hydrocarbons and, if present, CO are measured with the IR spectrometer and either the relative amount of hydrogen in the rich range or of O2+½ NO in the lean range is determined with the help of the signal (Ip) from the &lgr;-sensor. A &lgr; value is calculated from the measured exhaust gas component concentrations or relative amounts.