Abstract: The delivery of fuel into the combustion chamber of a diesel engine is aided by blowing in an amount of compressed air which is small compared to the stroke volume of the diesel engine after the stream of fuel has been injected into the combustion chamber via the fuel nozzle. In this way fuel particles which would otherwise remain in the injection nozzle and considerably increase the hydrocarbon content of the exhaust are removed from the nozzle and burned, at the same time clearing the nozzle holes of any remaining fuel. The compressed air blown in after fuel injection will assist combustion of the red-hot particles of the fuel stream which have formed immediately beyond the nozzle.

Abstract: In order to reduce the water content in piezoelectric GaPO.sub.4 crystal elements the proposal is put forward that each GaPO.sub.4 crystal element should be cut in its entirety from one uniform growth zone of a GaPO.sub.4 raw crystal bar and should not contain any zone boundaries, and that the piezoelectric GaPO.sub.4 crystal elements should be treated with a dehydrating solution, until an infrared coefficient of .alpha.<1.5 cm.sup.-1 is obtained at a wavelength in the vicinity of 2.0 .mu.m.

Abstract: An intake system for internal combustion engines, comprising suction pipes of different lengths, which can be connected individually--preferably in accordance with the engine speed--to the intake passage in the cylinder head leading to the intake valve. The main intake pipe is connected to each intake passage by means of a connecting piece, and three suction passages of different lengths departing from the main intake pipe open into this connecting piece either in the direction of its axis or on opposite sides thereof, the connecting piece containing a butterfly control valve which is centrally mounted on a shaft parallel to the longitudinal axis of the engine, and which--in its two extreme positions and in its center position--establishes the flow connection between one of the suction passages and the intake passage.

Abstract: The delivery of fuel into the combustion chamber of a diesel engine is aided by blowing in an amount of compressed air which is small compared to the stroke volume of the diesel engine after the stream of fuel has been injected into the combustion chamber via the fuel nozzle. In this way fuel particles which would otherwise remain in the injection nozzle and considerably increase the hydrocarbon content of the exhaust are removed from the nozzle and burned, at the same time clearing the nozzle holes of any remaining fuel. The compressed air blown in after fuel injection will assist combustion of the red-hot particles of the fuel stream which have formed immediately beyond the nozzle.

Abstract: An injection-type internal combustion engine with cylinders arranged in line, with two overhead camshafts, and four valves and a central pump nozzle for each cylinder, and with detachable rocker arms being provided on the cylinder head above the respective camshaft, for actuating the pump nozzles. With this arrangement, the cams for the rocker arms actuating the pump nozzles are operated from the two camshafts in turn, i.e., the first camshaft actuates the pump of one cylinder and the second camshaft actuates that of the adjacent cylinder, each rocker arm being mounted separately. This will facilitate assembly and disassembly of the pump nozzle including the corresponding actuating mechanism and valve gear.

Abstract: An engine brake in an internal combustion engine for use in motor vehicles, comprising an exhaust valve controlled by a cam via a follower lever, and a device for leaving the exhaust valve slightly open during the combustion stroke. According to the invention the support bearing of the follower lever is designed to be adjustable in the direction of the supporting force P between two extreme positions, i.e. one corresponding to normal operation and the other one to braking, such that on braking the exhaust valve is lifted by 0.3 to 3 mm, preferably 0.5 to 2 mm, during the phase in which the base circle of the cam is in contact with the follower lever.

Abstract: For the identification of the resonance characteristics of a piezo-electric transducer, an input signal having a variably selectable frequency is divided into two sub-signals of the same frequency to be tuned to one another, one of said sub-signals being independent of and the other thereof being dependent upon the electro-mechanical properties of a piezo-electric tranducer under test. A difference output signal is generated from the two sub-signals, this difference output signal being measured relative to a reference output signal derived from the input signal. The tuning of the two sub-signals in the measurement is undertaken constantly to zero and with a rated value actual value differential control of that part of the difference output signal lying in phase or, alternatively, 180.degree. out of phase with the reference output signal. The remaining part of the difference output signal which is phase-shifted 90.degree.

Abstract: In a method and apparatus for the evaluation of a starter motor current or of a magnitude proportional to it for determining the relative compressions of the cylinders of an internal combustion engine, in order to eliminate the distortion of the compression relationships between the individual cylinders, account is taken of the current/speed characteristic of the starter motor. Using a direct current series motor as the starter, from the starter current there is derived a magnitude N proportional to the actual speed according to the relationship N =1/i+k*i where i is the motor current. The correction factor K serves to take account of the departure of the characteristic from a hyperbolic curve.

Abstract: In a level measuring device for electrically non-conductive liquids comprising a sensor which is positioned in a vessel and is in contact with the liquid, and further comprising an evaluation circuit connected to this sensor both compensation of a changing dielectric constant and a high degree of accuracy and resolution are achieved by placing a driver electrode 5 in the lower part of the vessel 1 at a position essentually coaxial to the sensor electrode 3, 4, and by placing a compensating electrode 6 between the driver electrode 5 and the wall 8 of the vessel 1, such that further capacitors are formed between the two electrodes 5 and 6 themselves as well as between them and the sensor electrode 3, 4 and between them and the wall 8 of the vessel 1.

Abstract: For allocating to the respective cylinders cylinder-specific measured val taken from an internal combustion engine under test with the ignition suppressed the measured values are continuously numbered while the ignition is suppressed. After the suppression of the ignition has ceased the numbering is continued at least until the occurrence of the measured value from a cylinder determined by the ignition, after which, bearing in mind the known firing order of the engine, all the measured values can be allocated to the respective individual cylinders.

Abstract: In a valve-controlled compression-ignition engine with direct fuel injection and an intake passage inducing the inflowing air to rotate around the cylinder axis, an ideal combustion system has been found, combining the advantages of a diesel engine with direct fuel injection and an open combustion recess and those of a diesel engine with a pre-combustion or swirl chamber, while eliminating the main disadvantages of these two basic types. According to the proposals put forward by this invention the restricted passage or throat in the center area of the combustion chamber is bounded by means of a rotationally symmetric center part, whose lower end forms part of the toroidal combustion chamber, and whose top remains slightly below the fuel jet at the upper dead center of the piston, and which constitutes the inner boundary of the narrow ring-shaped scavenge passage leading from the combustion recess to the cylindrical throat, or rather to the cylinder itself.

Abstract: In an internal combustion engine with cylinders inline and an overhead camshaft for actuation of the intake and exhaust valves, the camshaft is driven from the crankshaft by means of a driving gear and an intermediate shaft, the driving gear being rigidly connected to an outer cheek of the crankshaft. With this arrangement the distance between the crankshaft bearings remains unchanged and a minimum overall length of the engine is achieved. At the same time a speed reduction gear may be located anywhere between the crankshaft and the camshaft.

Abstract: A transducer comprising a flexible piezoelectric layer as a sensor element for measuring mechanical quantities in hollow bodies, above all pressures in pipes, the opposite sides of this layer being bonded to electrically-conductive contact layers and being connectable via leads to a display and evaluation unit. In order to achieve a high temperature stability in such transducers and to make them suitable for use at temperatures exceeding 80.degree. C., the piezoelectric layer is proposed to consist of wurtzite or sphalerite. One of the electrically-conductive contact layers can be of some heat-resistant, flexible supporting material, for instance flexible metal foil, such as Cu-Be foil, or a sheet of plastic, one or both of whose sides are metallized, and the other electrically-conductive contact layer can be a metal coating applied by evaporation.

Abstract: In order to eliminate equipment-generated fluctuations during the periodic determination of a quantity to be measured which is effected by forming the difference between a measuring signal which has been altered relative to a source signal by the measurement variable and a reference signal which has remained unaffected relative to the source signal by the measurement variable, a base signal level is determined for each measuring cycle as the difference between the reference level and a zero level in the absence of a source signal, subsequent to which each actual reference signal level and each measuring signal level is compensated with the previously determined reference signal level. By amplifying the compensated reference signals prior to difference formation and standardizing the signal difference to the base signal level, a high degree of accuracy may be achieved even if the attenuations of the measuring signal caused by the quantity to be measured are very small.

Abstract: Two or more valves which are positioned opposite one another relative to a center plane in which the cylinder axis and the crankshaft axis are located and which are arranged in the cylinder head in a parallel, upright position, are actuated via separate cams and levers by a camshaft which is spaced from the center plane and extends in parallel with the crankshaft. The lever actuating the valve on the same side of the center plane as the camshaft is configured as a one-armed lever which is positioned underneath the camshaft and is supported by a bearing on the cylinder head. The lever actuating the valve on the other side of the center plane is configured as a rocker lever, its axle being situated above the one-armed lever, parallel to the camshaft.

Abstract: A pressure sensor which comprises one or more measuring elements situated in a housing and a plate membrane sealing the housing against the medium to be measured and being attached to the measuring element on order to transmit the pressure to be measured, the plate membrane having curved or conically-shaped part which extends into the interior of the housing and compensates for temperature shock drifting.

Abstract: An arrangement for the fluorescence-optical measurement of concentrations of substances contained in a sample includes a detector, a light source and a sensor element that includes a carrier element, the carrier element having an indicator layer on a portion thereof and an indicator-free surface, the carrier element being transparent to the radiation used, and having a refractive index which is greater than that of the ambient medium at the indicator-free surface, the light space being positioned such that the transmission of light from the light source to the indicator layer, and from there to the detector, is achieved, at least partially, by total reflection in the carrier element.

Abstract: A two-stroke internal combustion engine of the crankcase scavenging type, in which a nozzle connected to a lubricant feed line is provided in the intake passage for picking up oil from a lubricant reservoir via a partial vacuum. For simple and sufficient lubrication and cooling of the crank gear in accordance with the respective requirements of the engine, the nozzle (62) is positioned in the area of the smallest cross-section of a Venturi-tube-like part (60) of the intake passage, and an injection pump (54) is provided for fuel delivery, which eliminates the need for an oil pump.

Abstract: Devices for dividing the process of fuel injection into two phases, i.e., pre-injection and main injection, with a pressure relief body opening up an expansion space when the fuel injection pump has reached a given level of pressure, are known to be provided with a by-pass line which can shut off by a spring-loaded slide valve. A simpler design of such a pressure relief system is achieved by having the by-pass line lead from the expansion space to a by-pass opening which is located in the cylinder wall of the pressure chamber of the pump and is intermittently covered by the pump plunger, and by making this opening cooperate with control edges on the pump plunger, leaving it uncovered in the injection-free state.

Abstract: In a process for producing crystals in crystallographic point group 32 and corresponding to the comprehensive chemical formula APO.sub.4, wherein symbol A is a chemical element taken from the group Al and Ga, P is phosphorus and O is oxygen, from heated solutions of salts of group A in phosphorus acid, the application of acid concentrations within the range of 12.5 to 20 mol/l, solution temperatures within the range of 110.degree. to 190.degree. C. and total pressures within the range of prevailing static vapour pressure to 2.5 bar provides a simple, safe and cost-effective method of producing perfect, flawless crystals.