Abstract: An apparatus for cooperation with an existing opening within a cooling radiator of a vehicle for determining the liquid level in the radiator. The radiator, which may be an automobile or truck radiator, is connected to an electrical power source of the vehicle through the vehicle chassis. An insulator is established relative to the vehicle radiator in a substantially fixed relation. A sensor is mounted to the insulator for extending into the liquid in the radiator when a sufficient quantity of liquid is contained therein. The sensor has a plurality of curved surfaces for increasing the surface area of the sensor. An indicator interconnects the sensor with the electrical power source of the vehicle for indicating the level of liquid contained in the radiator by conductivity through the liquid in contact with the sensor. The increased surface area of the sensor enables the indicator means to be a conventional incandescent lamp connected in series with the sensor and the electrical power source of the vehicle.

Abstract: A device for detecting the presence of contaminating water in a fuel tank as well as for measuring the density of the fuel in the tank which includes an elongated body of optical material arranged to be mounted in a fuel tank in a vertically extending position, one side face of the body forming an interface with the fluid in the tank, and a plurality of light sensors on the opposite face of the body arranged in spaced-apart relationship, together with light-emitting means at the bottom of the body which emit a divergent group of rays of successively increasing angles of incidence upwardly so that those rays exceeding the critical angle at the interface for a fuel of a specific index of refraction are reflected to illuminate those sensors corresponding to the rays exceeding the critical angle to thereby provide a detected output representing the density of the fluid, the light-emitting means providing a second group of rays striking the lower portion of the interface which are reflected when water is present t

Abstract: Apparatus and method are disclosed for determining the level of a light-reflecting substance with regard to a reference point. The apparatus and method comprise directing a beam of light at the substance, receiving the diffuse reflected light on an arrangement of photoelectric sensor elements in a manner such that displacement of the reflected light from a predetermined position on the sensor element arrangement is sensed electronically, generating an electrical signal which is proportional to the displacement of the reflected beam from the predetermined position on the element arrangement, and using the electrical signal to determine the amount of deviation of the level of the substance from a predetermined reference point.

Abstract: A Blackburn-type liquid level gauge which is observed by a TV camera has its frontal display structure illuminated in an area where light is not being transmitted through the gauge by light which is refracted away from the TV camera and reflected back onto the face of the display.

Abstract: In a molten metal surface level detection system, the use of conventional detector means is eliminated and, instead, an ITV camera is provided at an appropriate place where it is neither thermally affected by the molten metal surface portion nor obstructs the site jobs and the molten metal surface portion is photographed by said ITV camera along a direction permitting the surveillance of the level of the molten metal surface and, then, the thus photographed image of the molten metal surface portion is processed in a suitable manner for accurately and reliably detecting the surface level thereof.

Abstract: A device enabling the operator of an internal combustion engine to visually inspect the quality and level of a fluid held within an associated fluid sump of the engine, transmission, or other adjacent fluid sump. The device operates directly from the vacuum system of the associated engine to selectively draw fluid from the sump upwardly into a viewing chamber. A lamp behind the chamber illuminates the fluid to facilitate visual inspection. If the fluid is below a prescribed level, no fluid will be drawn into the chamber, thereby indicating to the operator that the fluid level is below a specified minimum. The device may also be provided with a continuous monitoring system whereby fluid may be initially drawn into the visual inspection chamber and held there indefinitely or until the fluid drops below a prescribed level. When this happens, the continuous monitoring system may function to activate an annunciator giving warning to the engine operator that the fluid level is low.

Abstract: Monitoring the level of both opaque and clear liquids in a reservoir without contacting the liquids by providing first and second reservoir wall portions that define a region through which a light beam is passed from a light source to a light sensor so that opaque liquid extinguishes the light beam and so that the wall portions cooperate with the clear liquid to refract the light beam away from the sensor. A monitoring line segment, defined as the portion of a hypothetically unrefracted and unreflected light beam between the first and second reservoir wall portions, is a small fraction of the largest interior linear dimension of the reservoir in a plane containing the monitoring line segment and a line normal to the first reservoir wall portion.

Abstract: A material or liquid level sensing system is disclosed having a first triggerable pulse generator connected to a level sensor which is in turn connected to a second triggerable pulse generator wherein the first triggerable pulse generator supplies a pulse to the level sensor which transmits the pulse to trigger the second pulse generator for supplying an output both to an output device and to the first triggerable pulse generator to trigger another pulse to the level sensor and so on. In this manner, the first pulse generator supplied a subsequent pulse to the level sensor depending on whether or not the second triggerable pulse generator has received the previous pulse from the first triggerable pulse generator. Thus, the system continuously supplies pulses to the level sensor as long as the second triggerable pulse generator continues to receive pulses, but these pulses are blocked when the material or liquid being sensed is at a predetermined level and the output means is appropriately activated.

Abstract: The invention contemplates a sealed electrical-meter construction for measuring an electrical quantity such as an electrical resistance, and having particular application to the display of liquid-level where measured resistance is a function of observed liquid level. The meter construction provides a transparent side port at which a solar-cell assembly is exposed to external light, and the voltage output of the cell, after reduction to assure constant-voltage level is used to power the measuring circuit. Fiber-optics elements at the transparent side port convey light to the display face of the meter, so that even a flashlight at nighttime is sufficient to excite the solar-cell assembly and illuminate the display face.

Abstract: The level of a metallic bath, e.g. of an iron melt in an ingot mold, is determined by recurrent electro-optical scanning of the interior of the vessel along a narrow vertical strip zone. The output signals of the scanner are processed in an arithmetic unit which averages successive readings, to compensate for fluctuations, and may also receive a corrective signal in order to offset periodic level changes due to an intentional rocking of the vessel. The arithmetic unit may work into a visual indicator and into a controller adjusting the rate of inflow and/or withdrawal to maintain the bath level substantially constant.

Abstract: An optical device comprises a pair of contrastingly-colored sources of light, means for adjusting the brightness of the sources of light relative to each other, and a mixing element formed with a light-entrance portion to permit entrance into the mixing element of light emanating from the sources and with a display surface that communicates optically with the entrance portion and facilitates viewing of the light entering the mixing element through the entrance portion and propagated through the mixing element to the display surface, the light as displayed having a color that depends on the relative brightness of the sources. The mixing element has at least in part generally the shape of a cylinder formed with an axial bore so that the mixing element has an outer surface and an inner surface.

Abstract: An optical level detection probe is disclosed having first and second spaced apart optic guides, each guide having a 45.degree. angle reflecting face or surface opposing one another such that light traveling along the first optic guide will reflect off of its 45.degree. angle face, reflect off of the 45.degree. angle face of the second optic guide, and travel along the second optic guide for detection by a sensor as long as the material is below the reflecting surfaces. When the material reaches the reflecting surfaces, the light will be blocked.

Abstract: A liquid level monitor using the difference between the refraction of light by a prism in contact with air and by the same prism in contact with liquid being monitored to give warning of low liquid level. In preferred form for monitoring engine oil level, light is transmitted to a prism by an incoming fiber optic lead and returned from the prism by a return fiber optic lead. When the oil level is normal, the prism is in contact with the oil and the incoming light is transmitted into the oil and dissipated. When the oil level drops, the incoming light is reflected by the prism to the return lead and the reflected light is used to provide the indication of low oil level.

Abstract: A level sensing apparatus is disclosed having a source for supplying a signal having a predetermined frequency, a level sensor connected to the source and having an output for supplying an output signal having the predetermined frequency as long as the material, the level of which is being sensed, is not at a predetermined level, a frequency sensitive circuit for receiving the output signal from the level sensor and for providing an output whenever the frequency of the signal is above or below the predetermined frequency, and a load which is connected to be responsive to the output from the frequency sensitive circuit.

Abstract: A light-emitting element and a light-responsive element are optically connected with each other through a U-shaped optical guide. An output level of the light-responsive element indicates whether the U-shaped guide is above or below the liquid-level.

Abstract: A liquid level gauge for a tank, especially a pressurized railway tank car, has a housing with a bottom opening mounted at a top opening of the tank. A horizontal shaft is rotatably mounted in the housing between opposed walls having parallel flat vertical inner surfaces. A sprocket is fixedly mounted on the central part of the shaft, on each end of which is fixedly mounted a ring magnet spaced from one of these walls. Complementary ring magnets are rotatably mounted outside but adjacent these opposed walls. The four ring magnets constitute a pair of magnetic drives. A track and cable guide assembly, supported in the tank, extends from the bottom portion of the tank. A perforated tape is trained over the sprocket on the shaft and another sprocket rotatably mounted in the bottom portion of the tank so that the tape is under tension. A probe assembly connected to the tape moves vertically when the sprocket in the housing is rotated.

Abstract: A device for indicating when the level of developer solution in an electrostatic photocopying machine falls to a predetermined level comprises a source of light and a photosensor on which the light source is focused. The photosensor generates a light intensity signal that is related in a known way to the magnitude of light incident on it. Both the light source and photosensor are mounted in a housing, which has a bottom formed to rest firmly on the bottom of the tank that holds the developer solution, and, therefore, are mounted in fixed, spaced relation relative to each other as well as to the housing bottom. A bracket, which includes a spring, supports the housing in the developer solution tank with the housing and tank bottoms in firm interengagement to establish the predetermined developer solution level equal to the distance between the tank bottom and photosensor.

Abstract: Liquid fuel comprising hydrocarbon as its main component, which is in liquid state at normal temperature and pressure, is held in a container of an apparatus for vaporization of the liquid fuel to enable the fuel to be readily converted into a gaseous state for example for cooking purpose.

Abstract: A foam monitor senses the dissipation of foam within a transparent tube and employs a series of vertically spaced light emitting diodes which are cyclically pulsed to provide repetitive sequential scanning of the tube contents and a series of photo-responsive elements are axially spaced along the diametrically opposite side of the tube and positioned to monitor corresponding intermittent light paths that may be received from the corresponding light emitting diodes. The intermittent light paths are monitored during each scanning cycle to provide a pulse train which is indicative of the relationship between scanned levels containing foam and scanned levels void of foam. The pulses produced over a predetermined number of repetitive scans are totalized to provide an analytical measurement of the foam dissipation qualities for the liquid involved.

Abstract: In an optical detector which comprises on U-shaped transparent bar, a photoemitting diode disposed at one end of the bar and a phototransistor disposed at the other end of the bar, means for ensuring light-transmission is provided.

Abstract: A liquid level sensor for use when filling containers with hydrocarbons or other liquids is disclosed. A fiber optic bundle is arranged to form a flow path for a light beam in such a manner that the flow path is interrupted when the liquid level reaches a predetermined part of the flow path. The fiber optic bundle can be arranged to sense the liquid level when it approaches and reaches a predetermined height and can be connected to a loading control system in order to automatically control the filling of a tank.

Abstract: The present invention relates to an inspection glass light for the illumination and simultaneous observation of working operations in closed spaces having a lamp housing, an intermediate housing having a viewing window with the intermediate housing being mounted on a flange of an observation chamber.

Abstract: An optical-electrical liquid probe for sensing the presence or absence of a liquid comprises a light emitter and a light receiver housed within a translucent hollow body. When there is no liquid adjacent a sensing part of the body, the light rays from the emitter pass to the receiver by refraction through the walls of the body. The presence of liquid adjacent the sensing part of the body causes the light rays to be refracted in such a manner that they no longer reach the receiver with the result that the state of the receiver changes.

Abstract: A device for gauging level of a liquid within a container employing an elongated fibrous optic assembly which is connected at one end to a probe which is mounted within the container and at the other end to an electrical control device, the end of the fibrous optic assembly located within the probe being connected to a reflecting prism which functions to reflect light when not in contact with the liquid and does not reflect light when in contact with liquid, means located within the control device responsive to the reflection of light, said means being connected to an annunciator.

Abstract: An optical liquid level gauge is described for sensing and indicating the height of a liquid within a container, such as within a fuel tank. The gauge includes an optical liquid probe that has a plurality of U-shaped light pipes to be inserted into a tank. Each of the light pipes terminates in a U bend with the U bends of such light pipes being staggered in position relative to one another so as to be positioned at different liquid height indication levels within the tank. A source of light is provided for transmitting light into a first arm of each of the light pipes, and sensors are provided at the end of the second arm of each of such light pipes for detecting the amount of light transmitted from one end of the pipe to the other. The U bend of each pipe has a geometrical design which assures that when liquid is not present in the tank it transmits substantially all of the light received by it from the first arm of the light pipe into the second arm thereof for sensing by the sensor associated therewith.

Abstract: A device for the outside display of the level and specific density of a liquid contained within a tank, particularly for inflammable liquids, characterized by a plurality of paired light pipes having optical interface means therebetween located at intervals within a support with electrical means operable by light energy from one of the pair of light pipes being conducted thereby due to a mismatch of the index of refraction caused by an absence of fuel at the area of the optical interface to provide a display of the fluid level and/or the density of the fluid within a tank.

Abstract: A transparent fuel tank for motorcycles and like vehicles, in which an illuminator provides light to the plastic wall, not only giving a clearer indication of the level of liquid in the tank, but also having decorative and safety advantages as well.

Abstract: A plurality of luminescent elements, such as light-emitting diodes, incandescent lamps or the like, are located adjacent each other, each connected to the output of a difference amplifier. The respective inputs of the difference amplifier are connected, on the one hand, to a voltage divider to have different reference voltages applied thereto and, on the other, in common to the input voltage to be sampled so that, as the voltage changes between the amplification ranges of the difference amplifiers, the output therefrom will change in accordance with input voltage so that the brightness of the respectively connected luminescent elements will also change, thus providing gradual increase in brightness of any individual element as the voltage changes. The difference amplifiers may be differentially connected operational amplifiers.

Abstract: A combined visual and electronic liquid indicator which may be used as a battery hydrometer is disclosed. An outer housing of a generally cylindrical shape receives a centrally located elongated light transmitting viewing rod. The lower portion of the rod extends into a channel at the lower end of the outer housing. A float is retained in the channel by a retaining cage. A second generally cylindrical inner member which fits over the rod and into the outer housing has a light sensor and a light detector secured at its lower end across diametrically opposite portions of the float channel, and the outer housing and the inner member are then sealed together.