Abstract: The invention relates to a precipitation detector (1) and method for measurement of precipitation parameters. The detector (1) includes a frame (5), a surface (2) mounted on the frame (5) and adapted to receive hydrometeors, and detection means (3) for converting the impact impulses of hydrometeors into an electric signal. According to the invention, the surface (2) receiving the impact of the hydrometeors is convex, stiff and rigidly connected to the detector frame (4) with the detection means (3) being permanently connected to the surface (2) receiving the impact of the hydrometeors.

Abstract: The invention relates to a precipitation detector (1) and method for measurement of precipitation parameters. The detector (1) comprises a frame (5), a surface (2) mounted on the frame (5) and adapted to receive hydrometeors, and detection means (3) for converting the impact impulses of hydrometeors into an electric signal. According to the invention, the surface (2) receiving the impact of the hydrometeors is convex, stiff and rigidly connected to the detector frame (4) with the detection means (3) being permanently connected to the surface (2) receiving the impact of the hydrometeors.

Abstract: A measurement device and method for measuring tension in an optical fiber or wire. The measurement device includes a device for producing a vibration surge in the optical fiber or wire which vibrates at a certain, pre-selected frequency and advances as a linearly polarized wave. An optical location-sensitive detector measures the advancing speed (v) of the wave. An illuminator device illuminates the optical fiber or wire so that a shadow or an image of the vibrating fiber or wire is cast onto the indictor whereby the tension (T) of the optical fiber or wire is calculated from the equation T=v.sup.2 .multidot.M, when M is the fiber mass per unit of length of the optical fiber or wire. The indicator device measures the time at which a departing wave surge passes by the indicator and the time at which an arriving wave surge reflected from a subsequent coating vat, or other wave reflector, passes by the indicator.

Abstract: A detector indicating ice formation on the wing of an aircraft or any planear surface, based on a thread-like or a tape-like transducer, through which an ultrasonic signal is transmitted at one end. The attenuation of the signal having passed through the thread is measured with a receiver at the opposite end while the thread is simultaneously being heated such that ice that may surround it melts again, the attenuation thus resuming its initial level.

Abstract: The invention relates to an on-line tension meter for an optic fiber. The tensile stress of a bare optic fiber is measured without contacting the optic fiber as the optic fiber is drawn in a draw machine. A loudspeaker causes a wire wave to be formed in the fiber. The fiber tension is then measured by the advancing speed of the wire wave. The speed is measured by means of two location-sensitive electro-optic indicators or cameras, the distance therebetween being known.

Abstract: A theremometer or temperature alarm device making use of fibre optics. The measuring instrument has a fibre-optic light transmitter (1), which sends out light along an optic fibre (2) to a measuring head (5) on the end of the transmitting fibre (2), and a fibre-optic receiver (3), which is connected with an optic fibre (4) to the same measuring head (5). The measuring head (15) is a cell or hollow enclosure (6) which has been filled with a light-scattering substance (7) of the kind which below a certain threshold temperature scatters the incident light from the transmitting fibre (2) back to the receiving fibre (4) but above the threshold temperature characteristic for the substance (7) loses its light scattering capacity so that the light coming from the transmitting fibre (2) is no longer scattered to the receiving fibre (4).

Abstract: A liquid detector utilizing fiber optics, by which the presence of oils and various solvents can be detected. The detector is internally safe because the optical fiber is an insulator and may therefore be used to monitor liquids involving fire or explosive hazards. The detector may be used to detect leakage when storing oils and solvents, because it reacts most rapidly with these liquids. The detector makes use of capillarity of a sensing pick-up thereof, the optical reflection coefficient of the pick-up material changing as the pick-up material comes into contact with the liquid to be detected.

Abstract: A method and apparatus for measuring the tension of a thin, plane membrane (1). In accordance with the method, a burst of a membrane wave (2) is generated by a transducer element (3) e.g. a loudspeaker (3). The velocity of the membrane wave (2) is measured. The velocity measurement value of the membrane wave (2) is squared and multiplied by the basis weight of the membrane (1) in order to determine the tension. According to the invention, a light beam (10) is generated by at least one light emitting element (5), each light beam (10) is projected with help of projecting members (6 or 14, 15, 17) onto the membrane (1) in order to generate a light spot (4 or 19), the light spot (4 or 19) vibrating on the membrane (1) is converted into an electrical signal dependent on the position of the light spot (19) by means of at least one detector element (8 or 18 ) in order to determine the membrane wave (2) and the signal is processed in a processor (9) in order to determine the velocity of the membrane wave (2).

Abstract: The object of the present invention is to measure the magnitude of the friction and coefficient of friction or liquids with high viscosity or internal friction, such as molten plastic mix, e.g. in extruders by increasing the velocity of flow in a special measuring sleeve by stepwise reducing the flow cross section, whereby the flow velocity increases stepwise in accordance with the laws of hydrodynamics. When flow thermometers are installed at the points of reduction, the increase of friction energy can be assessed by the increase of temperature. When the temperature changes can be measured, the quantities describing the friction are calculable. The meter is applicable in numerous different situation and types of apparatus in which measurement of the friction energy is desired.

Abstract: The characteristics of various solid materials, in particular, surfaces of and coatings on metals and thickness of surface hardening layers are measured without damaging the specimen. The phase angle of a continuous thermal surface wave produced by a modulated light beam is measured. The phase angle of the continuous thermal wave progressing along the surface of the specimen is measured by temperature detectors either at a fixed distance from the light spot, as a function of frequency, or at a fixed frequency, as a function of distance. The phase angle of the thermal wave depends upon the thickness of the surface hardened layer whereby such thickness is measured.

Abstract: A detecting transmitter device installed in operative proximity with a surface to be observed includes an ultrasonic waveguide installed in such surface. Electronic equipment electrically connected to the ultrasonic waveguide transmits ultrasonic waves to the waveguide. The ultrasonic waves proceed in the waveguide. The equipment also receives the ultrasonic waves from the waveguide. The degree of attenuation of the waves in the waveguide depend upon the difference in viscosity and other mechanical properties of water and ice, whereby the detecting transmitter device and the electronic equipment detect freezing of the surface by attenuation of the waves in the waveguide.