Abstract: For achieving a constant capacity range by way of field weakening of a permanent magnet excited drive the magnetic transverse resistance (Rm) of the rotor plate pack is increased by pole gaps (P1, P2), which are produced by milling into the upper surface (O) of the rotor plate section (L), or are punched into the rotor plate section (L), whereby a covering of the poles of Tp in the range of from 70% to 80% has been shown to be particularly advantageous.

Abstract: An electric three-phase induction machine with six poles and 15 stator slots and a two-layer winding scheme is described. The induction machine has a smaller overall size than conventional machines with a greater slot number, without degrading the efficiency and/or torque characteristic of the machine. The machine can be manufactured cost-effectively and is useful for applications with synchronous spindles in machine tools.

Abstract: For achieving a constant capacity range by way of field weakening of a permanent magnet excited drive the magnetic transverse resistance (Rm) of the rotor plate pack is increased by pole gaps (P1, P2), which are produced by milling into the upper surface (O) of the rotor plate section (L), or are punched into the rotor plate section (L), whereby a covering of the poles of Tp in the range of from 70% to 80% has been shown to be particularly advantageous.

Abstract: A permanent magnet synchronous motor includes a stator and a permanent magnet excited rotor, with the stator provided with a winding which has cyclically repeating winding factors |&xgr;p|=0.945, |&xgr;5p|=0.140, and |&xgr;7p|=0.

Abstract: The invention relates to a method for determining small quantities of carbon monoxide and nitrogen oxides in gaseous mixtures containing oxygen with the aid of a sensor whose electrical resistance changes at a higher temperature with the carbon monoxide and nitrogen oxide concentrations. It makes use of the fact that, with suitable sensors, on the one hand the resistance-temperature curve of the one of the gases to be determined is clearly different from that of the reference mixture over a broad temperature range (gaseous mixture without the two gases to be determined) and, on the other hand, the resistance-temperature curves of the two gases to be determined approach one another in one part of this temperature range, or coincide, and maintain a clear distance from one another in another part of this temperature range.

Abstract: The invention relates to a sensor for the determination of carbon monoxide, especially in gas mixtures containing oxygen, on the basis of doped metal oxides whose electric conductivity is a function of the composition of the gas mixtures. Suitable metal oxides are those having n-type conductivity, the dopants used being other oxides of a metal having a maximum valency <4; oxides of a metal catalyzing the reaction of carbon monoxide with oxygen to give carbon dioxide, each in amounts from 0.01 to 0.2 mol %; and from 0.001 to 0.1 mol % of an oxide of a metal of the 5th subgroup of the Periodic Table of Elements. The sensors are notable for a small resistance-temperature coefficient while having high sensitivity and low hysteresis.

Abstract: An ignition system comprising one of a glow plug, spark plug and glow attachment having metal or ceramic surfaces which are exposed to a fuel/air mixtuer, and are at least partially covered with a coating comprising at least one complex metal oxide obtained as a result of a reaction of a basic oxide selected from a group comprising oxides of Si, Y, La and Ce and mixed oxides of the above-mentioned oxides with Al.sub.2 O.sub.3, with at least one further oxide selected from a group comprising oxides of alkali and alkali earth metals.

Abstract: Tin oxide doped with magnesium oxide or niobium pentoxide and prepared as a sintered material is found to be highly sensitive to oxygen partial pressure both in the presence of free oxygen and in the presence of oxidizable gases, such as carbon monoxide or the lower oxides of nitrogen, and even in the presence of mixtures of both, such as in the exhaust gas of an internal combustion engine. The electrical conductivity varies by substantially more than an order of magnitude in response to a change in the oxygen partial pressure of about one-half an order of magnitude. The doped oxides operate as poor catalysts for the oxidation of oxidizable components of the exhaust gases. Chromium oxide doped with tin oxide shows the effect of an excessively good catalysis from the point of view of range of measurement, but is usable to give a sharp indication of the appearance or disappearance of free oxygen in a gas mixture.

Abstract: The present invention provides a catalyst for converting the noxous CO, NO.sub.x and hydrocarbons found in the exhaust gases from internal combustion engines into less harmful gases, and to the method of treating said exhaust gases. The catalyst consists essentially of a solid solution of Fe.sub.2 O.sub.3, Cr.sub.2 O.sub.3, and Fe.sub.3 O.sub.4. The catalyst may be extended on a porous carrier such as aluminum oxide or aluminum silicate. The catalyst is particularly suited for treating the exhaust gas from internal combustion engines of motor vehicles.