Abstract: In the measuring chamber the flow of the fluid to be monitored impinges at an angle upon the end window of the measuring probe. Due to the thus occurring self-cleaning action, no deposit forms at the end window and which deposit would falsify the meaurement. In the event of small fluid quantity throughputs and flow rate and thus insufficient cleaning action, a nozzle ia provided for producing a jet which is directly aimed at the end window. The fluid is irradiated in the region of the measuring probe by using ray guides. If particles causing turbidity are contained in the fluid, the rays will be reflected, collected by the optical system and supplied to a receiver through a ray guide.

Abstract: With the heretofore known monitoring systems the parameters or magnitudes to be monitored are converted into electrical signals and transmitted, by means of electrical lines or conductors, to a central station. Because electrical signal transmitters are undesired, particularly in explosion endangered atmospheres or surroundings and, further, since spurious signals can be induced in electrical signal lines, proposals have already been made to utilize monitoring apparatuses working with optical signal conductors. The different embodiments of feelers of the invention, for optical monitoring apparatuses, enable monitoring the continuous change and/or exceeding a predetermined threshold, of electrical, mechanical and thermal parameters or the like.

Abstract: Conventional warning installations possess electrically interrogated feelers or sensors or generate electrical signals, particularly if they are used for remote monitoring purposes. At the feelers and even more so at the signal lines it is possible for there to be produced spurious signals due to electrostatic charges or electrical or magnetic induction. These spurious signals trip unwarranted warning or alarm signals. The novel warning or alarm installation therefore contains an optical conductor or guide as a signal line, and the feelers are interrogated by means of optical signals. The optical conductor together with an electronic monitoring circuit forms a free-running opto-electronic oscillator which comes to standstill when there is interrupted the oscillating optical signal which is irradiated into the optical conductor and radiated back out of the conductor into the circuit.

Abstract: An electrooptical instrument for detecting the presence of liquid and a method of operating the same, comprising at least one monochromatic infrared source, a light conductor which totally reflects infrared radiation from at least one surface thereof, an infrared detector, and signal processing circuitry. According to the invention the infrared source has a maximum radiation strength of less than 200 mW/sterad, the main maximum in the angular distribution of the infrared radiation is at least approximately axially symmetric and oriented in the direction of the optical axis of the light conductor, and the angular distribution of the infrared radiation is such that the intensity falls off to half its maximum value less than 4.degree. away from the symmetry axis. An electronic circuit causes the system to oscillate when no liquid is present. The instrument may be operated in a self-monitoring mode by monitoring the oscillations with two monostable multivibrators connected in parallel.

Abstract: An electro-optical device for the detection of the presence of a liquid, comprising at least one monochromatic infrared transmitter arranged at the region of a hollow body probe composed of a synthetic high molecular substance and totally reflecting the infrared radiation. There are also provided at least one infrared receiver and a circuit for signal processing. At least at the region of at least a boundary surface which totally reflects the infrared radiation the hollow body probe consists of a halogen-containing polymerizate.

Abstract: An electro-optical apparatus for the detection of the presence of liquid, comprising at least one monochromatic infrared transmitter arranged at the region of a hollow body probe composed of synthetic, high molecular material and totally reflecting the infrared radiation. There are further provided at least one infrared receiver and a circuit for signal processing. The hollow body probe composed of the synthetic, high molecular material or substance is connected by means of a detachable fluidtight connection composed of a further synthetic, high molecular material of the same substance group with a support having at least one hollow chamber or space.

Abstract: The presence of an organic liquid is detected by means of a probe which comprises a rubber-like material which is swellable in an organic liquid, which rubber-like material has electrically-conductive solid particles distributed therethrough, in such concentration as to touch each other.

Abstract: A method of, and apparatus for, the non-mechanical conveying of a collected quantity of liquid from a lower level to a higher level wherein through freeing of flow paths a quantity of a heavier liquid located at the higher level flows to the lower level and while utilizing the different specific gravities of both liquids there is conveyed an at least approximately equal volumetric quantity of the lighter liquid to be conveyed to the higher level.The apparatus for the performance of the aforesaid method aspects embodies a container located at the higher level and which is filled with the heavier liquid, this container being in flow communication with the lighter liquid located at the lower level.