Abstract: A liquid leveling device comprising a length of flexible transparent tube and a liquid control assembly at each end of the tube for preventing inadvertent leakage of liquid from the tube end but to maintain atmospheric communication with the liquid in the tube during use of the leveling device. The liquid control assembly includes a closed hollow body elongated along a central axis which is normally vertically oriented and having valve structure operatively associated with an air passage through the body. Contained within the body is a float means responsive to liquid flowing from the tube into the body which operates the valve structure and closes the air passage, preventing liquid leakage from the leveling device.

Abstract: A device and method for locating two or more points on a horizontal plane is disclosed. The device emits an audio or visual signal when fluid in a tube reaches a designated level. When the signal is given, the fluid at the other end of the tube will be on the same horizontal plane, thereby enabling the user to locate points on the horizontal plane.

Abstract: An elevation indicator comprising a supporting base, a reservoir for holding liquid supported on the base, an elongated staff and a flexible tube extending from the staff to the reservoir. An elongated scale is mounted on the staff for longitudinal movement relative to the staff and a transparent tube is also mounted on the staff and extends along one side of the staff adjacent the scale. A check valve is located at the top of the transparent tube and the bottom of the transparent tube is connected to the flexible tube, so that liquid can flow between the reservoir and the transparent tube.

Abstract: In an electronic apparatus for measuring a difference of elevation between two points, said apparatus comprising: a tube made of a flexible material; a fluid with a low viscosity completely filling said tube; two piezoelectronical pressure transducers each connected to a source of electrical power and mounted at one extremity of the tube in contact with the fluid filling said tube to produce signal a proportional to the pressure of this fluid; electronic means connected to each of said piezoelectrical pressure transducers for processing the signals received from said transducers, said processing means comprising means for generating a signal proportional to the difference between the signals received from the transducers and means for converting said generated signal into a value indicating the difference of elevation between the extremities of the tube, and means for displaying said value indicating the difference of elevation, the improvement wherein it further comprises means for generating a signal propor

Abstract: There is disclosed a hydrostatic leveling system including a pair of indicator heads connected by a liquid hose for equilizing static pressure in the liquid mercury pools of the indicator heads and a gas hose for equalizing the gas or vapor pressure within the heads above the pools of mercury. Each head is a float connected to the stem of a precision measuring gauge with graduations on the order of ten-thousandths of an inch. The indicator heads have identical structures and thus when they are resting on a level surface they may be reversed in location without change in gauge indicator reading; any difference in the reading is a measure of out-of-level condition. The space for the pool is sealed with a very flexible diaphragm between the float and the wall of the pool cavity. A plunger in the cavity is operated by a solenoid in the cavity to periodically thump the float to reduce tendency to stick due to surface tension, friction and hysteresis.

Abstract: Apparatus for comparing the level of two spaced points, to find which is higher or lower, and possibly also for determining the magnitude of the difference in level of the points. The apparatus comprises two chambers that communicate with each other through a flexible conduit. The conduit and the lower portion of each chamber is filled with liquid, preferably mercury, whose level in each chamber varies as the elevations of the chambers relative to each other. An electric circuit interconnects the chambers; and the circuit is opened or closed upon variation in the relative levels of the chambers; or the amount of current flowing in the circuit is progressively changed with changes in the relative elevation of the chambers. Various embodiments of circuit for achieving this are disclosed, including make-or-break contacts, a variable capacitor, a variable resistance slide wire, and a variable resistance deformable strain gauge.

Abstract: A device for measuring height despite difficult visibility comprises a small portable water tank positioned at the location to be measured and a pressure transducer placed at a reference location and connected with the water tank by a hose, whereby the transducer outputs a signal voltage proportional to hydrostatic pressure and hence to the height of the first location. The output signal is amplified and converted to a digital value which is displayed by a digital display calibrated in terms of height.

Abstract: A hose water leveling instrument in which a thin hose is filled with liquid and has an end to which a fixable reference instrument is connected. Another end of this hose has connected to it a freely-movable reading instrument. The housing of the reference instrument has on its rear side, a mounting surface with adhesive characteristics. A contacting section next to this mounting surface has a measuring scale which is easily read from different directions. An automatically opening and closing venting valve prevents run out of this measuring liquid, and is located in the reference instrument which is permanently filled with measuring liquid. The venting valve is in the form of a plane-convex body located in a valve chamber.

Abstract: A pair of upright stands are provided and include enlarged bases by which the stands may be supported on variously elevated support surfaces. Each stand has a vertically elongated support mounted thereon for adjustable vertical positioning therealong and each stand has a scale thereon by which the positioning of the support therealong may be precisely determined and adjusted as desired. Each support includes an upstanding transparent tube section and the lower ends of the tube sections are connected by an elongated flexible connecting tube member including an expandable and contractable reservoir.

Abstract: Disclosed herein is apparatus for measuring elevation and including an elongated conduit adapted to be filled with liquid and having opposite ends, and a first pressure sensing transducer connected to one end of the conduit for measuring the fluid pressure in that end and including means for producing a first pressure indicative signal. The elevation measuring apparatus further includes a second pressure sensing transducer in fluid communication with the other end of the conduit for measuring the pressure of fluid at that end and including means for producing a second pressure indicative signal, and means for processing the output signals of the pressure sensing transducers, to produce an elevation differential readout.

Abstract: A device providing a movable reference point for use in leveling objects such as house trailers and the like which extend over large areas. The device includes a reservoir which is carried on a stand that has a plurality of tubes extending out the bottom thereof. The tubes have magnets carried on the outer ends thereof for readily attaching to the object to be leveled. A screw jack is connected to the reservoir for raising and lowering the reservoir and the level of the liquid therein so as to set the liquid level in the tubes to a desired height. The tubes can be moved around the trailer without affecting the reference point.

Abstract: An elongated flexible level assembly usable as a transit or the like includes a pair of float assemblies each having a flow passage thereinto adjacent the lower end, a pair of valve seats within the chamber of the housing in spaced relationship above the flow passage thereinto and valve members reciprocable in the chamber to seal the flow passage through the valve seats. Indicator means is provided on the housing intermediate the two valve seats, and the housing is transparent at least about the indicator means so as to permit viewing of the water level therein. A flexible conduit interconnects the flow passages of the two float assemblies and liquid is introduced into the assembly in a volume sufficient to fill the conduit and the two float asemblies to the level of the indicator means.

Abstract: Apparatus for determining the difference in height between two widely spaced apart locations utilizes a length of hose filled with fluid. A pressure transducer is secured to each opposite end of the hose in a position to be influenced by fluid pressure incidental to the hose ends being disposed one at each of the locations. The transducers are electrically connected to a source of power and to instruments which cooperate to provide an indication of the difference in elevation between the two locations.

Abstract: A tiltmeter which uses two fluids of different thermal density coefficients, each of which is contained in its own fluid system consisting of a long tube connecting two vertical reservoirs. The two systems are deployed in physical contact along their entire length so that they experience the same thermal conditions. Measurements with this instrument are made by taking separate, simultaneous readings of the difference in fluid heights and/or bottom fluid pressure between the terminal vertical reservoirs in each of the two fluid systems; these measurements, together with known density coefficients of the fluids, provide the data to correct for errors in meter readings caused by temperature/density fluctuations in the fluids and permit a precise determination of vertical displacement and tilt over the measurement path. The ruggedness and unique design of this tiltmeter allow it to make more accurate measurements of regional tilt than previous tiltmeters and with less expenditure of money and effort.

Abstract: An instrument for indicating levels above an irregular surface. A liquid reservoir of uniform internal cross section, having a scale on a transparent side wall indicating distances above and below a zero mark, is connected by a flexible duct with the bottom of an elongated transparent tube mounted on an elongated rod, the latter having a scale indicating distances above the bottom thereof. A pair of endless tapes is mounted for movement along the length of the tube. The tube is flat in cross section. The cross sectional area of the reservoir is larger than that of the tube, the ratio being an integer greater than one, and the ratio of the divisions on the scales on the reservoir and on one of the movable tapes is spaced in inverse ratio. The rod carries a movable guide which can be set to different positions to enable an operator to indicate positions at predetermined levels.

Abstract: Apparatus for measuring the vertical displacement between a remote point and a reference point. The apparatus comprises a pair of reservoirs, each having a liquid working fluid disposed therein, a differential pressure transducer and a hydraulic coupling means for each of the reservoirs. Each hydraulic coupling means couples a point in the reservoir below the top surface of the working fluid to an associated input port of the pressure transducer. A vapor pressure equalization means is provided for the reservoirs whereby the points above the top surface of the working fluid in each reservoir are maintained at substantially equal pressures. The apparatus further includes a volumetric temperature compensation means for offsetting temperature dependent changes in the volume of the working fluids which occur in the hydraulic coupling means.

Abstract: A multi-limbed manometer system adapted to detect and record the vertical displacement of different parts of a large structure, e.g., the pedestals and cylinders of a steam turbine installation. The datum level of the liquid in the system is adjusted by changing the pressure of a head of liquid connected to the system, for example, by raising and lowering a reservoir of the system or by moving a piston in a cylinder connected to the system. The floats comprise homogeneous structures having a multiplicity of small air-filled compartments, e.g. an epoxy resin containing air-filled hollow glass balls having a diameter of about 150 microns. A float in a reference limb provides a reference signal indicative of the actual liquid level which is compared with a signal indicative of the desired liquid level and a difference signal derived and used to raise and lower the reservoir or move the piston in the cylinder.