Abstract: The tank-level gauge comprises an outer tube sealed at its lower end and adapted for attachment to the top wall of a tank. The gauge also comprises two telescoping rods axially movable within the outer tube. A float encircles the outer tube. Magnets respectively attach to the float and to the lower end of the inner gauge rod, whereby a rising level causes such inner rod to rise as well. When the liquid level reaches a predetermined level, the inner gauging rod becomes disconnected and a magnet on the outer gauging rod becomes coupled to the float magnet, whereby the outer gauging rod continues to rise. Indicia on the inner gauging rod provide information on the height of the liquid in the tank from its empty condition to a partly full condition. Indicia on the outer gauging rod provide information on the quantity of liquid in the tank from its partly full condition to its full condition.

Abstract: An apparatus for providing a signal to indicate liquid level above a pre-determined level in a container. The apparatus includes a device for defining a fixed reference level. An alarm unit having an alarm and an alarm actuator is connected to the defining device. A float is connected to the alarm unit and rests on the surface of the liquid. The float actuates the alarm actuator to activate the alarm when the surface of the liquid reaches the pre-determined level.

Abstract: A liquid level indicator for storage tanks including a cover member for covering an opening at the top of the storage tank, a central rod extending downwardly from the cover member into the storage tank, and a float movably disposed on the central rod. A vertically movable first rod assembly is connected to an upper portion of the central rod, and a vertically movable second rod assembly is connected to a lower portion of the central rod, with the float being disposed therebetween so that the float contacts and moves the first rod assembly when the storage tank is substantially filled, and the float contacts and moves the second rod assembly when the storage tank is near empty. Switches are associated with each of the first and second rod assemblies to activate signal members when either of the first and second rod assemblies are vertically moved to indicate when the storage tank is substantially filled or when the storage tank is near empty.

Abstract: A plurality of spaced reed switches vertically aligned for positioning in a liquid. Each of the reed switches vertically overlaps the adjacent above and below reed switches and the longitudinal axis of the reed switches is at an angle to the vertical. A float carries magnets and is movably positioned coaxially about the plurality of switches. An electrical indicator is connected to the switches for indicating the vertical position of the float relative to the switches.

Abstract: A sewer alarm is provided for warning of overflow conditions in a house trap installed in a sewer line, the sensing mechanism consisting of a magnetic float switch with no moving parts other than the float itself and with the magnetic activating switch sealed from the hostile environment found in a house trap. The alarm cap member housing the magnetic float switch has physical dimensions similar to a typical cap installed in an unalarmed house trap and substantially has only wires protruding from its exterior face.

Abstract: A remote oil tank display apparatus is set forth in combination with an oil tank for the indication of oil tank volume. The sending unit is encased in a hermetically sealed container to prevent oil fume propagation throughout an area. A combination digital and light emitting diode display is set forth and is remotely positioned relative to the oil tank to enable individuals of diminished physical capacity to receive and display information of oil volume remaining in an oil tank. Further, an audio means may be selectively employed in concert with the visual displays to assist individuals of diminished hearing capacity.

Abstract: A fuel level sender including a vertically reciprocal foam float that carries a slideable dual contact member biased by springs in the float toward a thick-film resistor plate.

Abstract: An automatic reading gauge is provided and consists of an elongated flexible measuring member having a scale thereon with a float affixed to one end and a counterweight at other end. The measuring member is disposed within an O-shaped body having a weep hole, an air check valve and a top sight area. When the body is placed through a filler hole to extend to bottom of a tank, the amount of fluid within the tank will be indicated at the top sight area.

Abstract: An apparatus is disclosed for determining the thickness of a layer of aerated sludge floating on a layer of heavier liquid in a tank used in the treatment of sewage. The apparatus comprises a frame which can be positioned to extend vertically into the tank, an indicator supported by and movable vertically with respect to the frame, the indicator being positionable at the highest level of sludge in the tank, a horizontally-extending lower base attached to the frame at or near the bottom thereof, a horizontally-extending upper base attached to the frame at or near the top thereof, and a line carrying a float, the line being movably secured at the upper and lower base. The float is movable between the upper and lower base, is floatable on the liquid, and includes a horizontally extending portion presenting an upwardly directed, generally planar surface.

Abstract: The liquid level in a tank is determined by measuring the current supplied to an elctromagnet from which a rod having a specific gravity greater than that of the liquid is suspended in the liquid.

Abstract: The pressurized magnetic float level indicator for recipients containing liquids at high pressure and temperature of the invention comprises a tubular body with a vertical axis which is closed at its ends and communicates at the top and bottom with a recipient containing liquid whose level is to be indicated, within which there is a float provided with a magnetic element designed to orientate a plurality of rotary magnetic dipoles aligned in parallel with the tubular body, the float being provided with inner rings and being pressurized with an evaporating mixture having a steam pressure which varies with variations in the internal temperature of the float along a curve corresponding to the variation of the pressure with the temperature of the liquid contained in the recipient and in the tubular body externally to the float, this steam pressure within the float at least partially balancing out the pressure outside it.

Abstract: A liquid level control in a refrigeration system operates a solenoid valve to maintain the level of liquid refrigerant in a vessel within a range defined by predetermined lower and upper liquid levels, sounds an alarm if the upper level is exceeded and stops a pump if the lower level is violated. The control comprises a float assembly and a switching assembly. The float assembly comprises a float chamber connected to the vessel, a float ball therein, a vertically extending float rod connected to the float ball and movable along a vertical path, and a pair of spaced apart stop members on the float rod disposed within the switching assembly. The switching assembly comprises a switch actuator permanent magnet, having magnet poles at opposite ends, slidably mounted on the float rod between the stop members and movable thereby along the said path.

Abstract: Apparatus for detecting the level of a liquid. A metal-detecting proximity sensor is placed near a non-metallic, vertically-positioned guide shaft. A float is placed on the liquid. A tube has one end attached to the float and the other end insertably placed within the guide shaft. A piece of metal is placed within the tube. When the apparatus is used for determining when the level of the liquid reaches a predetermined value, the metal piece has a boundary which is located at the height of the proximity sensor only when the liquid level is at its predetermined value. When the apparatus is used for measuring the level of the liquid, the proximity sensor has an output signal proportional to the distance from itself to metal and the metal piece has an outer surface whose distance to the proximity sensor at the height of the proximity sensor, changes with changes in the liquid level.

Abstract: A level gage mounting structure comprising a level gage secured to an upper member of a liquid storage container and vertically extending inside the container, the level gage having its lower end supported on the bottom surface of the container, and a deformable member provided between the upper member and the upper end of the level gage to support the upper end of the level gage, the deformable member being deformable vertically in unison with any vertical deformation of the upper and bottom surfaces of the container, thus enabling the lower end of the level gage to be in contact with the bottom surface of the container at all times.

Abstract: A fuel level sensor 16 comprises a vertical member 20 and float 22 wherein said vertical member 20 comprises a steel substrate 26 encased in porcelain 28 with a thick film cermet resistive track 34 deposited thereon. A nickel deposit 36 at the bottom portion of the vertical member 20 facilitates electrical continuity between the substrate 26 and the resistive track 34 such that the substrate acts as a buried conductor enabling proportionality between magnitude of resistance and liquid level while diminishing the likelihood of conductor erosion and float interference.

Abstract: A vehicle fuel level sensor comprising a hollow cylindrical body housing a sliding float, the position of which is determined by the fuel level in the fuel tank. The sensor also comprises a filter surrounding as portion of the side wall of the cylindrical body, close to the bottom wall of the same, so as to define, with the side wall, a first chamber; and a plate for supporting the filter and connected to the bottom wall of the hollow cylindrical body so as to define, with the bottom wall, a second chamber communicating directly with the first chamber and, via a through hole in the bottom wall, with the inside of the hollow cylindrical body.

Abstract: The device is of the type comprising a magnet carried by a float and a magnetically actuable electric contact carried by a support element which also performs the function of guarding the float. The most important characteristic of the device is that of providing positioning means which maintain the float constantly centered with respect to the support element during excursions of this latter caused by the hydrostatic thrust exerted by the liquid.

Abstract: Process and apparatus for measuring liquid level changes in horizontally disposed cylindrical storage tanks compensates for thermal expansion and contraction of the liquid in the tank during the measurements. A vertically disposed substantially cylindrical container in the storage tank has a valve which controls fluid communication between the container and the storage tank. A float and associated sensing mechanism measure the level of liquid in the container. A measurement of the liquid level is made in the beginning of the test with fluid communication open between the container and the tank. A second measurement is taken after a fixed time period during which fluid communication between the container and the tank is closed. From the second measurement a theoretical liquid level is calculated which would exist in the tank due to temperature effects, and without leakage.

Abstract: A water level indicator useful for signalling a plurality of different water levels within a bathtub. The device has clamping means for removably securing the indicator to the tub, a depending float chamber for projecting into the tub and a battery operated sound alarm system. A float and rod assembly are housed within the float chamber. The rod projects through an opening in the top of the indicator and is provided with a plurality of metallic bands which will complete an electrical circuit to sound the alarm.

Abstract: A liquid level sensing means for use in a tank or the like, adapted to hold a liquid which is partially withdrawn and/or replenished from time-to-time. Disposed within the liquid is a buoyant, upright, hollow reed switch-like float element having a longitudinal axis parallel with the direction of movement of the liquid level within the tank. The switch element is adapted to float upon the surface of the liquid whose level is to be sensed. It is provided with an upper reed and a lower reed, each in alignment with the longitudinal axis of the float element. The upper reed is rigidly secured to the upper end of an envelope of the float element, while the lower reed thereof is spring biasly secured to the lower end of the float element envelope. At a location medially between the upper and lower ends of the float element envelope, there exists an area of overlap between the unsecured ends of the upper and lower reeds respectively.

Abstract: A device for detecting the level of a liquid contained in a tank, for example the level of the fuel contained in the tank of a motor car. The device comprises a vertical bar inserted in the tank and a float movable with respect to the bar to follow the variations in the level. The bar, which is of insulating material, acts as a supporting element for a printed circuit having at least one continuous conductive track and a variable resistor parallel to the continuous track. On the float there is mounted a metal element which simultaneously contacts both the conductive track and the variable resistor.

Abstract: In a boiling liquid cooling system of an engine, first and second coolant level sensors are disposed in a coolant jacket of the engine which respectively detect first and second coolant levels therein. The second coolant level is higher than the first coolant level. A control circuit employed in the invention functions so that when, with the coolant in the coolant jacket being at its boiling point, the coolant in the radiator is at a temperature higher than the freezing point of the coolant, the first level sensor becomes enabled disabling the second level sensor thereby to keep the coolant level in the coolant jacket at the first coolant level, while, when, with the coolant in the coolant jacket being at its boiling point, the coolant in the radiator comes to its freezing point or points around the same, the second level sensor becomes enabled disabling the first level sensor thereby to keep the coolant level in the coolant jacket at the second coolant level.

Abstract: A fuel tank for motorcycles and other like vehicles. The fuel tank has a filling up indicating device comprising a float which can float on fuel stored in the tank; a stem which is attached to said float, and extends upwards to have an indicator at the top; and a support member which is installed inside a fuel supply port to vertically slide and support said stem.The configuration provides for simple information that the tank is being topped up when refuelling, thus preventing fuel from overflowing.

Abstract: A fluid flow indicator including a magnetic switch mounted adjacent a fluid carrying conduit. A magnetic plunger is loosely contained by the conduit and is urged to the proximity of the switch by fluid flow through the conduit thereby activating the switch. The magnetic plunger is restricted to movement within the monitoring conduit by rods transverse to the fluid flow, one located at the inlet and the other located at the outlet of the monitoring conduit, and having their termini operatively received and retained in annular channels formed in the walls of the monitoring conduit. A process for fabricating a fluid flow indicator as claimed herein is also taught.

Abstract: A liquid level indicator includes a magnetized float and a plurality of magnetized indicator elements which are pivoted by the float magnet and which have distinguishable opposite surfaces to provide the liquid level indication, the indicator elements being formed from a material which provides magnetic fields of opposite magnetic polarity which extend substantially continuously along the opposite edges of the indicator elements.

Abstract: A liquid level sensor adapted to be installed inside a reservoir of a liquid to be monitored. The level sensor includes a float made from magnetic material which moves between two opposed end positions along a predetermined up-and-down path following the top surface level of the liquid. An a.c. coil driven by a pulse generator is located at one end of the float path such that the magnetic material of the float is closer to the coil at this one end of the path than at the opposite end, and is thus a variable part of the "core" of the coil which changes in response to the liquid level in the reservoir. The magnetic flux generated by the coil and/or its inductive reactance, also being a function of the variable core and thus a function of the liquid level, can be monitored electrically to provide an indication of the liquid level to an operator. The level sensor can be used to provide a signal at a predetermined level, or to provide an output which is proportional to the level of the liquid in the reservoir.

Abstract: A water level indicator for a pressure vessel is provided which employs a plurality of vertically spaced cantilevered mounted spring members. The free end of each spring member is connected to a depending float member. The float member has sufficient mass and density to depress its spring member when the float member is in a gaseous medium. The float member has sufficient buoyancy to elevate its spring member when the float member is in a water medium. One or more strain gauges is secured to each spring member to indicate the instantaneous position of the spring member and thereby provide an indication of the instantaneous water level.

Abstract: Apparatus for the visual indication of the level of liquid contained in boilers, tanks, reservoirs or the like is described, comprising an outer tube connected to the receptacle and having a float which contains a permanent magnetic dipole. Adjacent the tube is a column of rotatably mounted bi-colored cylinders, some of which show one color and the rest another when viewed from one direction, to indicate the level of the liquid. In accordance with the invention, the permanent magnetic dipole is automatically orientated by the magnets in bi-colored cylinders as it is mounted rotatably about a vertical axis.

Abstract: A flexible stick tank gauge is made of a thin metal or plastic tape. The tape is sufficiently thick to be self-supporting when held vertically from the lower end. Alternatively, the tape is curved to be a narrow sector of a cylinder. Measuring indicia are applied to at least one surface of the tape. The tape remains flexible at extreme environments of temperatures and will not break in normal use such as airline fuel measuring operations.

Abstract: The present invention relates to an improved liquid-level indicator. The liquid-level indicator comprises an upstanding tube and a float arranged for vertical movement therein. This float is provided with a permanent magnet which is polarized in a horizontal plane and influences magnetically an array of display elements. These display elements are located outside of the tube. The display elements are rotatably supported and arranged in succession one above the other. Between the display elements and the tube there extends a magnetic strip arranged such that the permanent magnet of the float is oriented towards the display elements. This magnetic strip also pre-tensions the display elements. It is located outside of the tube and at a distance from the float.

Abstract: This guage is adapted to measure the depth of fluid flowing past a flume or weir in a generally horizontally disposed conduit. It comprises a transparent tube or stilling well which contains a float, and which is adjustably secured by a pair of clamps to an elongate supporting rod. The float can be clamped against movement in the well by a hose, which extends downwardly in the bore of the well, and which is sealed at its lower end. The hose is connected at its upper end to a manually-operable vacuum device which can be manipulated either to collapse or expand the hose. In use the hose is collapsed and the lower end of the supporting rod is inserted downwardly into a conduit to support the lower end of the well a predetermined distance above the bottom of the conduit, and in advance of the associated weir or flume.

Abstract: An improved indicator for fill content of a fire extinguishing system including a pressure vessel having an outlet through which the fire extinguishing material may flow. The indicator includes a non-magnetic, closed housing, mounted on the vessel and having one end within the vessel and the other end exteriorly of the vessel. At least one of the vessel and the housing are sealed to the atmosphere and a visual access opening is provided on the exterior end of the housing to allow one to look into the interior of the housing. A tape is mounted within the housing for movement in a path past the visual access opening and includes indicia along its length.

Abstract: A housing unit is constructed substantially in a tightly closed state and divided by a partition into two chambers, one for encasing a fuel gauge and the other a strainer. The housing unit, on being attached to a fuel tank, simultaneously functions to indicate the amount of fuel in the fuel tank and strain the fuel to remove foreign matter therefrom.

Abstract: A float is disclosed for use in tank gauging systems of the type having a vertically supported guide. The float includes a donut-shaped body member adapted to be positioned about the guide to ride freely with the liquid surface. A discharged tube is positioned concentrically with the body member by a number of support members. The discharge tube is positioned below the liquid surface and acts as a discharge electrode to maintain the path of least resistance for an electrostatic discharge of the float below the liquid surface.

Abstract: An apparatus for indicating the level of a surface of a fluid in a tank including a vertically disposed non-magnetic column provided on the tank and coupled to the tank such that the fluid in the tank flows into the column, a non-magnetic level indicator housing provided on the column, a plurality of horizontally disposed magnetic rotors rotatably coupled to the housing, a float provided in the column and a magnetic member provided in the float.

Abstract: Method and apparatus for sensing moisture by exposing water in a container to the atmosphere, sensing changes in the volume of the exposed water due to ambient weather conditions, controlling an electrical signal related to the sensed change and controlling the operation of an irrigation system, such as a plurality of solenoid-actuated pilot valves associated with sprinklers of the irrigation system, in response to the signal.

Abstract: A liquid gauge mechanism of the type primarily designed to be used in containers utilized for maintaining or growing plants therein wherein the casing of the gauge mechanism is at least partially submerged within the root system and surrounding liquid so as to indicate the level of liquid within the container. An indicator element is movably disposed within the hollow container of the gauge mechanism and has indicia formed thereon so as to be viewable through the casing of the indicator means. The level of liquid within the container is the same as the level of liquid within the casing. The indicator element being floatable within the casing serves to position the indicia thereon in aligned relation with a window or viewing portion through the casing so as to indicate the level of the liquid relative to the root system of the plant maintained within the container.

Abstract: The level of liquid in a tank or a boiler is determined initially by enclosing the liquid in a column and then sensing the liquid surface in the column by causing a plunger to pass through the non-liquid medium in the column above the liquid to the liquid surface and noting the abrupt change in descent rate of the plunger when it hits the liquid surface due to the great difference between the viscosities of the non-liquid and liquid mediums. The level of liquid in the boiler is reflected on a continuing basis by permitting the plunger to float or levitate in or on the liquid as it is supported by an entrapped gas bubble. The difference in the position of the plunger when it encounters the liquid surface and the position of the plunger thereafter, as it is supported on the liquid is the correction factor that is maintained steadily until pressure or temperature changes necessitate a new determination of that difference with a fresh gas bubble at the current temperature and pressure.

Abstract: Disclosed is a magnetically actuated fluid-level indicator for indicating the level of a fluid contained in a vessel having a gauge tube attached thereto and having a magnet-containing float floating in the gauge tube, the indicator comprising a plurality of interlocking elements united with one another, wherein each element comprises a support body and a magnetically actuated indicator means supported thereon.