Liquid Levels With Magnetic Transmission Patents (Class 73/DIG5)
  • Patent number: 6089086
    Abstract: A float-type liquid level gauge is provided for measuring the level of a liquid such as LPG within a horizontally oriented cylindrical tank (228). The gauge includes a movable pivot arm (212) supporting a float arm assembly (225) and coupled by gears (207, 214) to a magnet shaft (206, 208) and magnet (210) mounted in a rigid support arm (204) through a sideways-securing shaft channel(209). The support arm is connected to the lower side of a gauge head (202) and the magnet extends into a passage (52) in the gauge head so as to be magnetically coupled to a level indicating dial (226) provided on the upper side of the gauge head. The lower portion (302) of the support arm is angled and offset with respect to a longitudinal axis (265) such that a high ratio can be obtained between the gears while still permitting the components of the gauge to pass through the opening of a standard pressure fitting (234).
    Type: Grant
    Filed: July 2, 1998
    Date of Patent: July 18, 2000
    Assignee: Rochester Gauges, Inc.
    Inventors: Danny E. Swindler, Amber N. Dudley, Herbert G. Ross, Jr.
  • Patent number: 6041650
    Abstract: A float-type liquid level gauge is provided for measuring the level within a tank of liquids such as liquified petroleum gases. The liquid level gauge includes a movable float arm (30) coupled by gears (46, 48) to a magnet shaft (26) and magnet (28) mounted in a rigid support arm (24) through a side-accessible shaft passage (110). The support arm is connected to the lower side of a gauge head (22) and the magnet extends into a passage (52) in the gauge head so as to be magnetically coupled to a level indicating dial (34) provided on the upper side of the gauge head.
    Type: Grant
    Filed: August 26, 1997
    Date of Patent: March 28, 2000
    Assignee: Rochester Gauges, Inc.
    Inventors: Danny E. Swindler, Amber N. Dudley, Herbert G. Ross, Jr.
  • Patent number: 5988701
    Abstract: A by-pass level indicator includes a main tube in communication with a tank via a pair of by-pass tube members, a float containing a magnet and an indicator attachably mounted to the main tube and having a series of magnetic colored flags reacting with the magnet of the float for indicating level of the tank. Each of the by-pass tube members includes a T-joint having an upright tube receivably engaging with one end of the main tube and a transverse tube integrally extending from the upright tube communicating the main tube to the tank. The transverse tube has a male threaded end portion to partly receiving an O-ring. The by-pass tube member further has a combination of a union and a collar adapted to communicating the transverse tube with the tank. The collar is threadingly engaged with the male threaded end portion of the transverse tube and clamps a connecting tube of the union to the transverse tube simultaneously compressing a protruding portion of the O-ring, thereby achieving a fluid-tight seal.
    Type: Grant
    Filed: January 15, 1998
    Date of Patent: November 23, 1999
    Inventor: Ting-Kuo Wu
  • Patent number: 5862702
    Abstract: Both ends of a sensing probe are sealed by an assembly including a fixing disk, a sensing probe, a sensing circuit, a floating collar and an external tube is provided. The fixing disk is provided with a threaded opening in which one end of the sensing probe is fixedly attached. The sensing probe is built-in with a sensing circuit. A floating collar is movably enveloped onto the sensing probe. The external tube is further attached to the fixing disk and the inner diameter of the external tube is larger than the outer diameter of the floating collar. The other end of the sensing probe is provided with an inner threaded portion. A locking cover is provided with a pair of openings and a post in a central portion. The post is provided with an external threaded portion in which the inner threaded portion of the sensing probe can be engaged. The post further includes a threaded recess in which a bolt having a small collar can be attached. The fixing disk further includes an annular extension at its bottom.
    Type: Grant
    Filed: June 26, 1997
    Date of Patent: January 26, 1999
    Inventor: Chung-Ho Liang
  • Patent number: 5829303
    Abstract: A method and apparatus for measuring a liquid level using a liquid level gauge having reed switches to determine the position of a magnetic float. Firstly, providing an elongate float having an axial bore defining a longitudinal axis. The float has a plurality of magnets axially spaced along the longitudinal axis to form magnetic layers. Secondly, providing a tube having a first end and a second end. A plurality of magnetically activated reed switches are equally axially spaced from the first end to the second end. The tube extends through the axial bore of the float. Thirdly, determining which of the plurality of magnetically activated reed switches have been activated by the axially spaced magnetic layers of the float and interpolating float position in relation to the activated reed switches.
    Type: Grant
    Filed: June 20, 1996
    Date of Patent: November 3, 1998
    Inventor: George David Fraser
  • Patent number: 5743137
    Abstract: A magnetic float assembly is provided, comprising (i) a generally cylindrical paramagnetic (e.g. stainless steel) float enclosure having first and second closed end portions located at opposite ends of a longitudinal axis running the length thereof, and having a generally cylindrical interior surface located between the end portions, (ii) a first annular magnet disposed within the float enclosure at a first location along the longitudinal axis and having an outer surface which substantially corresponds to the generally cylindrical interior surface, and (iii) and a second annular magnet disposed within the float enclosure at a second location along the longitudinal axis and having an outer surface which substantially corresponds to the generally cylindrical interior surface. The first and second annular magnets are separated by a paramagnetic (e.g. aluminum or titanium) spacer.
    Type: Grant
    Filed: November 9, 1995
    Date of Patent: April 28, 1998
    Assignee: Clark-Reliance Corporation
    Inventors: David E. Brown, David E. Purcel
  • Patent number: 5718146
    Abstract: A waste level detector including a holder fixedly secured to a vehicle's cesspool by screws, an elongated probe extended downwards from the holder and disposed inside the cesspool, a float movable along the probe, a magnet fixedly secured to the float, a detecting circuit mounted inside the elongated probe to detect the elevation of the magnet, a perforated cylindrical casing having a top end threaded onto the outer thread on the holder and covered around the probe and a bottom end covered with a perforated end cap, and a cover covered on the holder above the cesspool.
    Type: Grant
    Filed: July 5, 1995
    Date of Patent: February 17, 1998
    Inventor: Chung-Ho Liang
  • Patent number: 5645336
    Abstract: Lighting assemblies are provided for visual indicators which indicate the level of fluid in a container. One such assembly comprises a backlighting assembly for a visual fluid level indicator having front and rear transparent viewing windows for viewing the level of a fluid contained therein, comprising (i) a substantially flat fiber optic panel located proximate the rear transparent viewing window; (ii) an attachment mechanism for attaching the substantially flat fiber optic panel to the visual fluid indicator proximate the rear transparent viewing window; and (iii) an illumination source optically coupled to the substantially flat fiber optic panel. The illumination source is a gas filled light source operating at less than 25 volts A.C. which is enclosed in a waterproof and explosion-proof enclosure, and which is optically coupled to the fiber optic panel by a fiber optic light cable.
    Type: Grant
    Filed: May 29, 1996
    Date of Patent: July 8, 1997
    Assignee: Clark-Reliance Corporation
    Inventors: David E. Brown, Mark A. Colman, Michael J. Kett
  • Patent number: 5479820
    Abstract: A gauge for measuring fluid level, especially cryogenic fluids, having a head assembly with a passageway to receive the upper portion of a lift rod assembly. The lift rod assembly includes a spring attached at the upper end to the head and at the lower end attached to a spring guide. A lift rod is mounted adjustably on the spring guide, and the upper end of the lift rod has attached a magnet and the lower end of the lift rod a displacement member. The upper end of the lift rod is received in the passageway of the head. Attached to the head adjacent to the passageway is a dial assembly adjustably mounted in relation to the passageway of the head.
    Type: Grant
    Filed: October 12, 1993
    Date of Patent: January 2, 1996
    Assignee: Rochester Gauges, Inc.
    Inventor: Nicholas M. G. Fekete
  • Patent number: 5478966
    Abstract: The detector is a foldable one constructed of unit elements 1a-1n connected with each other through hinge members 6. The members 6 are staggered in arrangement along the longitudinal direction of the unfolded or stretched detector so as to permit the detector to be folded in staggered manner. In storage and transport, the detector is folded to facilitate its handling. In installation, the detector is unfolded or stretched to assume a long-reach form to facilitate its installation in a liquid-level gauge system of a storage tank 13.
    Type: Grant
    Filed: November 9, 1994
    Date of Patent: December 26, 1995
    Assignee: Tokyo Keiso Kabushiki-Kaisha
    Inventor: Tokio Sugi
  • Patent number: 5435181
    Abstract: Disclosed herein is an electronic float gauge for indicating the level of liquid in a tank. A float follows the liquid level and causes a rotor that has magnets on it to rotate. Surrounding the magnets, in a concentric array, are a series of reed switches. The rotation of the magnets feeds information to the reed switches about the level of fluid in the tank. The reed switches are connected to a fluid level indicator.
    Type: Grant
    Filed: September 29, 1993
    Date of Patent: July 25, 1995
    Assignee: The Kelch Corporation
    Inventor: Ronald E. Koebernik
  • Patent number: 5357815
    Abstract: A gauge assembly (10) utilizing a voltage divider circuit to provide reliable and accurate measurement of a fluid level within a tank (16) or other environment. A pointer assembly (52) pivots about an axis (42) in response to a moving float to indicate the fluid level. A plurality of contact arms (114, 116, 118) extending from a contact plate (58) on the pointer assembly (52) resiliently engage a point (120) along a resistive element (88). The first end of the resistive element is connected to a voltage regulator (100) which is connected to a first contact (94). The second end of the resistive element forms a second contact (96). The point (120) of contact between the contact arms and resistive element is connected to an amplifier (102) which is connected to a third contact (95) forming a low impedance voltage divider circuit.
    Type: Grant
    Filed: December 29, 1993
    Date of Patent: October 25, 1994
    Assignee: Rochester Gauges, Inc.
    Inventor: Cecil M. Williamson
  • Patent number: 5347864
    Abstract: An improved liquid level measuring apparatus having a plurality of spaced reed switches having a microprocessor attached to the liquid level measuring sensor apparatus. The switches are wired together in parallel and in sets and are addressed by a shift register for providing a parallel to serial shift of the switch status position to the microprocessor. This allows a reduction in the number of conductors existing the sensor and providing an output signal indicating the vertical position of a float relative to the switches. A microprocessor control notes any inoperative switches, disregards the reading of the inoperative switches in calculating liquid level, and provides stored information to the measurement process for compensating for defective switches.
    Type: Grant
    Filed: April 12, 1993
    Date of Patent: September 20, 1994
    Assignee: Electrolab, Inc.
    Inventors: Karl A. Senghaas, Peter Senghaas, Jing Wang, Pete T. Kolonko, Jr., Jerzy Michalec
  • Patent number: 5347849
    Abstract: The apparatus of the invention is a water level probe comprised of a probe body, a sleeve having openings permitting fluid flow and encasing part of a magnetostrictive sensor, and an external housing encasing electronic circuitry for processing and transmitting the electric signal generated by the magnetostrictive sensor and sealing the circuitry from fluids. The sensor comprises a float slidably mounted on a rod, the float designed to float in water but sink in a petroleum product, thereby ensuring that it will float at the interface between the water and the product. The water level probe is used in the method of the invention to measure the depth of the water in a vessel storing hydrocarbon product at predetermined time intervals. The longitudinal angle of inclination of the vessel with respect of the horizon having previously been determined, the volume of water in the vessel is calculated from the depth measurements.
    Type: Grant
    Filed: July 22, 1992
    Date of Patent: September 20, 1994
    Assignee: Tanknology Corporation International
    Inventors: Mahan L. Reeme, Barry N. Williams, Glenn A. Kauffman
  • Patent number: 5299456
    Abstract: A dipstick for measuring oil levels provides an electronic indication when oil in an internal combustion engine sump is low or high. The electronic dipstick does not have to be removed as is normal for most dipsticks which determine level from observing a wet line on the stick. The dipstick has an elongated member for insertion into an aperture of a sump, the member has a high mark and a low mark thereon representing oil level in the sump. A float is mounted for movement within a cage integral with the elongated member, the float having a magnet to activate a switch. A first switch is associated with the high level and a second switch is associated with the low level. An indicating arrangement indicates when the magnet in the float activates either the first switch and/or the second switch.
    Type: Grant
    Filed: June 30, 1992
    Date of Patent: April 5, 1994
    Inventor: Steiner George A.
  • Patent number: 5291782
    Abstract: An Eddy current position sensor for providing an electrical signal proportional to the position of a metallic ring positioned around and movably positionable axially along the length of an elongated wire wound core. The metallic ring serves as a movable target with respect to the fixed coil/core and may be made buoyant for liquid level measurement or connected to other movable objects. The electrically conductive wire winding around the elongated preferably cylindrical ferromagnetic core has a progressively increasing spacing between each turn of wire from one end of the coil to the other. Each end of the wire is connected to a linear oscillator and signal conversion unit which serves to both input a radio frequency current through the coil and to monitor the absorption of the metallic ring around a conical shaped electromagnet field produced by the energized coil. The field absorption by the metallic ring varies linearly with the axial positioning of the ring over the coil.
    Type: Grant
    Filed: February 16, 1993
    Date of Patent: March 8, 1994
    Inventor: Howard E. Taylor
  • Patent number: 5233869
    Abstract: A fire fighting trainer for use in training fire fighters is provided. The fire fighting trainer includes a structure having one or more chambers having concrete or grating floors. Each chamber contains one or a series of real or simulated items such as furniture and fixtures and equipment. The trainer has a smoke generating system with an outlet for each chamber. The trainer also includes a propane gas flame generating system. The trainer has a main control panel for regulating the flame generating system and the smoke generating system and for controlling the fire, or fires, and smoke in each chamber. The trainer also has a sensor assembly in each chamber, which senses water.
    Type: Grant
    Filed: April 24, 1992
    Date of Patent: August 10, 1993
    Assignee: Symtron Systems, Inc.
    Inventors: William Rogers, James J. Ernst, Steven Williamson, Dominick J. Musto
  • Patent number: 5187988
    Abstract: Apparatus for measuring the flow of a fluid medium which flows upward through a substantially vertically mounted tube section having a suspended body in the tube section. The vertical position of the suspended body depends on the intensity of the flow. Movement of a magnet, movable with the suspended body, is sensed by a unit which includes a Hall sensor and an electronic evaluation circuit, responsive to the Hall sensor output, develops an output signal corresponding to the flow of the medium.
    Type: Grant
    Filed: March 26, 1991
    Date of Patent: February 23, 1993
    Assignee: Fischer & Porter Company
    Inventors: Hans J. Dettmer, Jorg Herwig, Joachim Hagemann, Werner Marchewka, Michael tzfeld
  • Patent number: 5156048
    Abstract: A fluid level detector comprises a tank including a sleeve portion extending vertically from a bottom section of the tank to a top section of the tank, and sensor device mounted to a circuit board connected at one end to monitoring device, with the circuit board being inserted into the sleeve. There is a circular float assembly with a center aperture. The circular float assembly includes a pair of magnets mounted in push-pull orientation at opposite sides of the aperture within the float assembly. The float assembly is slidably positioned over the sleeve whereby the float assembly moves up and down the sleeve as the water level changes in the tank, wherein the sensor device generate a signal representing detection of fluid level by the sensor device when the fluid level in the tank is substantially at the level of the sensor device.
    Type: Grant
    Filed: December 17, 1991
    Date of Patent: October 20, 1992
    Assignee: Pitney Bowes Inc.
    Inventors: Carlos L. DeFigueiredo, George J. Doutney
  • Patent number: 5150615
    Abstract: A fuel sensing and monitoring apparatus and method is disclosed. The apparatus includes two spaced conductive coils constituting a primary and secondary winding of a transformer. A short coupling member is mounted to a movable member to which a float is attached, the float being located in the fuel tank of a vehicle. The float and movable member move in response to a change in fuel level in the tank. When the fuel level changes, the short coupling member moves relative to the primary and secondary windings. This movement adjusts or alters the transformer coupling between the primary and secondary and produces a variable output signal which can be correlated, through the use of appropriate circuitry, to a representation of the level or fuel in the tank as indicated by the position of the movable member to which the float is attached.
    Type: Grant
    Filed: August 7, 1991
    Date of Patent: September 29, 1992
    Assignee: Nartron Corporation
    Inventors: Michael J. Rymut, Stephen R. W. Cooper, John M. Washeleski
  • Patent number: 5148709
    Abstract: A gauge (10) is disclosed which provides advantages in accuracy and cost. A head (16) is mounted on a reservoir containing a fluid to be monitored. A cylindrical support tube (28) is secured to the head and extends into the fluid. A head bushing (40) and a bottom bushing (42) are secured at opposite ends of the tube (28) and support a helically twisted center shaft (48) for rotation about an axis. The center shaft passes through a float (60) which is guided for movement along the axis by guide ribs (34, 36) on the support tube.
    Type: Grant
    Filed: December 11, 1991
    Date of Patent: September 22, 1992
    Assignee: Rochester Gauges, Inc.
    Inventor: Herbert G. Ross, Jr.
  • Patent number: 5136884
    Abstract: A magnetic sight gage sensor comprises a sensor for determining the liquid level in a process vessel utilizing a magnetic float on the interior of a tube. The tube is connected at different levels to a process vessel and contains a liquid that is maintained at the same level as the liquid inside the process vessel. A magnetostrictive displacement transducer is coupled to the tube or sight glass on the exterior of such glass, so it is out of the process fluid. The transducer provides signals indicating the position of the float relative to a reference position on the transducer. The tube or sight glass is made of a non-magnetic material in order to allow transmission of the magnetic field from the float to the transducer.
    Type: Grant
    Filed: April 17, 1991
    Date of Patent: August 11, 1992
    Assignee: MTS Systems Corporation
    Inventor: Rodley C. Lovett
  • Patent number: 5136883
    Abstract: A liquid level gage system is disclosed. This system includes a displacer secured to a cable and movable in response to winding or unwinding said cable around or from around a rotatable drum. The rotatable drum is coupled to a driven shaft, and a drive assembly is provided to drive the driven shaft. An indicator subsystem is included which provides an indication of a change in the apparent weight of the displacer as the displacer is moved across a liquid level. A strain gage is a key component of the indicator subsystem. In one embodiment, an assembly is provided for powering the indicator subsystem and transferring data from the indicator subsystem which involves two pair of coils. In another embodiment, the gage system can be effectively remotely programmed using light signals.
    Type: Grant
    Filed: August 24, 1990
    Date of Patent: August 11, 1992
    Inventor: Louis J. Jannotta
  • Patent number: 5124686
    Abstract: The gauge has an outer tube sealed at its lower end and adapted for attachment to the top wall of the tank, and an inner tube axially movable within the outer tube. A float encircles the outer tube and moves freely therealong. First and second magnets respectively attached to the float and to the lower end of the inner tube provide magnetic coupling therebetween so that a rising liquid causes the inner tube to rise with the float. Magnets within the inner tube operate a switch to signal when the first and second magnets are in position for magnetic coupling therebetween. Another magnet is fixed by a set screw to the outside of the inner tube in position for operating the switch when the tank is substantially full. Retaining clips are also disclosed for holding the latter magnet in place.
    Type: Grant
    Filed: December 31, 1990
    Date of Patent: June 23, 1992
    Assignee: Midland Manufacturing Corp.
    Inventors: John J. White, Gaston C. Barmore, Jr.
  • Patent number: 5117693
    Abstract: A liquid level detector includes a pivotally mounted bent arm which supports, adjacent opposite ends thereof, a float and a component of a signal generator. As the level of a fluid contacted by the float rises and falls, the opposite end of the arm will move into proximity to or away from a support. The second component of the signal generator is mounted on the support and a signal indicative of the juxtapositioning of the second end of the arm to the float will be generated.
    Type: Grant
    Filed: June 13, 1991
    Date of Patent: June 2, 1992
    Inventor: Thomas R. Duksa
  • Patent number: 5103674
    Abstract: A method of measuring the level of a corrosive, high-pressure, high-temperature liquid in a closed container of a nuclear reactor, by providing a generally tubular structure connected to the closed container of the nuclear reactor so that the level of liquid in the tubular structure is indicative of the level of liquid in the closed container, providing a sealed buoyant float sized to move vertically up an down within the tubular structure, the float being formed of beryllium, detecting from outside the tubular structure the vertical position of said buoyant float, the position corresponding to the level of liquid in the closed container.
    Type: Grant
    Filed: December 17, 1990
    Date of Patent: April 14, 1992
    Assignee: Massachusetts Institute of Technology
    Inventors: John O. Outwater, Gordon F. Kohse, Michael J. Driscoll, Otto K. Harling
  • Patent number: 5083115
    Abstract: A liquid-level detecting structure includes a housing disposed in a tank in proximity to a wall surface of the tank, a float disposed inside the housing and adapted to be moved by the liquid which has entered the housing, and a passage provided for introducing the liquid into the housing and having an opening facing the wall surface of the tank. When acceleration has acted toward the wall surface of the tank with the liquid level being close to a minimum level, the liquid is biased toward the wall surface. Accordingly, the opening of the passage is immersed in the liquid, preventing the float from being further lowered. Meanwhile, when acceleration has acted toward a wall surface opposite to the adjacent wall surface, this acceleration is oriented in an opposite direction to the direction in which the liquid flows out of the opening of the passage, so that the liquid in the housing is prevented from flowing out of the passage.
    Type: Grant
    Filed: January 16, 1991
    Date of Patent: January 21, 1992
    Assignee: Asmo Co., Ltd.
    Inventor: Atsushi Kamiya
  • Patent number: 5079950
    Abstract: A level indicating assembly for use in a tank mounted in a vehicle, such as an RV or boat, includes a fitting body for mounting the assembly in the top of the tank, and probes extending through the body into the tank. At least one of the probes has a hollow probe shaft which is of a flexible material such as flexible pvc. One of the probes provides an "empty" indication for the tank, while the other probes provide a "full" indication, and a mid-level indication. A socket or like element with a knock-out plug optionally provides a vent in the fitting body. During installation the position of the probe shafts with respect to the fitting body are adjusted, and any unneeded portion of the probe shaft above the shaft fitting is cut off.
    Type: Grant
    Filed: May 3, 1990
    Date of Patent: January 14, 1992
    Assignee: Sealand Technology, Inc.
    Inventors: Edward McKiernan, Ronald J. Bailey, James A. Sigler
  • Patent number: 5076101
    Abstract: A system for sensing the level of contents in a container is disclosed. A tubular member is vertically disposed in the container and sealed from the contents of the container. A marker located in the tubular member and generating a peripheral polarized magnetic field, is levitated at the height of float means located around the tubular member buoyed on the contents of the container and generating a polarized magnetic field within the tubular member of like polarity beneath the polarized magnetic field of the marker. A depth transducer located at one end of the tubular member forms part of a pulse-echo ranging system which calculates ranges on the basis of a time lag between emission of an ultrasonic signal by the depth transducer and receipt of at least one return echo signal from the marker in order to determine the depth of the marker in the tubular member, and indirectly, the level of contents in the container.
    Type: Grant
    Filed: December 21, 1990
    Date of Patent: December 31, 1991
    Assignee: Federal Industries Group Inc.
    Inventor: Gary P. Lazure
  • Patent number: 5020367
    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.
    Type: Grant
    Filed: September 4, 1990
    Date of Patent: June 4, 1991
    Assignee: Midland Manufacturing Corp.
    Inventor: John J. White
  • Patent number: 4986124
    Abstract: In a screened inductance sensor having a drive winding, a sense winding, and a conductive screen for varying the induced voltage in the sense winding by reason of the eddy currents generated in the conductive screen in the presence of the drive field, a physical barrier is interposed between the region of the sensor in the windings are located and the region in which the screen is located. These regions are fully environmentally isolated from each other by the physical barrier. The construction is especially suited to screened inductance level gauges, in particular for fuel tanks, where the conductive screen is part of a float assembly in contact with the fuel, but the electrical windings are kept dry in a separate portion of the gauge.
    Type: Grant
    Filed: June 15, 1988
    Date of Patent: January 22, 1991
    Assignee: Kollmorgen Corporation
    Inventors: John V. Byrne, Francis McMullin, Aengus Murray
  • Patent number: 4976146
    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.
    Type: Grant
    Filed: March 30, 1990
    Date of Patent: December 11, 1990
    Inventors: Karl A. Senghaas, Peter Senghaas
  • Patent number: 4958665
    Abstract: An apparatus for adjusting the level of a liquid filling a packaging tube comprises a float for use as suspended in the liquid filling the tube, a magnet attached to the float, and a magnetic sensor for detecting from outside the tube variations in the intensity of magnetism due to the upward or downward movement of the magnet to produce an output signal. The level of the liquid in the tube is adjusted in accordance with the output signal of the sensor.
    Type: Grant
    Filed: November 16, 1988
    Date of Patent: September 25, 1990
    Assignee: Shikoku Kakoki Co., Ltd.
    Inventor: Fumiyuki Iwano
  • Patent number: 4951506
    Abstract: The position sensor of the present invention includes a pair of elongated conducting members disposed in a parallel arrangement and a conducting metallic ball or mercury drop freely movable following the pair of elongated conducting members while maintaining a simultaneous contact with the pair of elongated conducting members, which combination provides two electric circuits respectively including a first circuit including a first poriton of the two elongated conducting members and the contact provided by the metallic ball or mercury drop, and a second electric circuit including the second portion of the two elongated conducting members and the same contact, wherein the metallic ball or mercury drop divides the combination of the two elongated conducting members into the first and second portions.
    Type: Grant
    Filed: May 12, 1988
    Date of Patent: August 28, 1990
    Inventor: Hyok S. Lew
  • Patent number: 4924703
    Abstract: The gauge has an outer tube sealed at its lower end and adapted for attachment to the top wall of the tank. The gauge also has an inner tube 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 tube, whereby a rising liquid causes the inner tube to rise as well. When the liquid level reaches a predetermined high level, a pencil-type magnet mounted within the inner tube operates a switch in an alarm box mounted in the top of the outer tube.
    Type: Grant
    Filed: May 5, 1989
    Date of Patent: May 15, 1990
    Assignee: Midland Manufacturing Corp.
    Inventors: John J. White, Robert H. Dean
  • Patent number: 4922764
    Abstract: A constant pressure cylinder with a spheroid or ellipsoid mixer is disclosed herein. Improvements include a spheroid or ellipsoid mixing element for mixing the accumulated sample. The mixing element is free to move about the sample chamber but is consturcted in such a way to avoid damage to the interior cylinder walll. Other generally ellipsoid shaped mixing elements are also disclosed. The invention additionally incorporates an improved piston for use in the cylinder. The piston contains a magnet assembly which may be used in conjunction with an invention by a third party to visually display the location of the piston in the cylinder.
    Type: Grant
    Filed: September 12, 1988
    Date of Patent: May 8, 1990
    Assignee: Welker Engineering Company
    Inventor: Brian H. Welker
  • Patent number: 4911011
    Abstract: A gauge assembly (10) is disclosed which incorporates a voltage divider circuit to provide reliable and accurate measurement of a fluid level within a tank (16) or other environment. A pointer assembly (52) pivots about an axis (42) in response to a moving float to indicate the fluid level. A plurality of contact arms (92, 94, 96) extending from a contact plate (58) on the pointer assembly (52) resiliently engage a point (91) along a resistive element (84). The ends of the resistive element (84) form first and second contacts (86, 88) while the point (91) of contact between the contact arms and resistive element is connected to a third contact (90) to form a voltage divider circuit.
    Type: Grant
    Filed: November 1, 1988
    Date of Patent: March 27, 1990
    Assignee: Rochester Gauges, Inc.
    Inventors: Nicholas M. G. Fekete, James R. Howeth
  • Patent number: 4912407
    Abstract: An inductance coil serves as a displacement sensor arranged in connection with a tuned circuit of an oscillator. Liquid level displacement in an LEC crystal growth environment is sensed as a frequency change in the oscillator circuit as compared to a set point value. The sensor is protected from the environment by an outer protective sheath of non-conductive, non-contaminating material such as boron nitride.
    Type: Grant
    Filed: November 23, 1988
    Date of Patent: March 27, 1990
    Assignee: Allied-Signal Inc.
    Inventors: Devlin M. Gualtieri, Edward Porbansky, Mandayam C. Narasimban
  • Patent number: 4875370
    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.
    Type: Grant
    Filed: February 7, 1989
    Date of Patent: October 24, 1989
    Assignee: Witronic Elektronische Gerate Gesellschaft M.B.H.
    Inventor: Martin Spitzer
  • Patent number: 4870862
    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.
    Type: Grant
    Filed: June 3, 1988
    Date of Patent: October 3, 1989
    Assignee: Cesare Bonetti
    Inventor: Giulio Bonetti
  • Patent number: 4841782
    Abstract: A target fluid flow indicator gauge comprising a non-magnetic housing defining a target chamber having a rounded portion that is curvilinear about an axial center that is coaxial with a fluid flow central axis through the gauge, with the chamber rounded portion lying in a plane that extends normally of such axial centers, a leaf spring mounted in the housing chamber and adjacent one end of the spring, which leaf spring at the other end of same has fixed to a rigid lever arm that mounts a disc-like target in centered relation within the chamber portion with the housing further defining inflow and outflow fluid ports on opposite sides of and centered on the axial centers and on the target for directing fluid flow against the target and out of the chamber; the lever arm carries a driving magnet assembly adjacent the target that is magnetically coupled through an imperforate wall structure of the housing to an externally located follower magnet assembly that acts through a short lever arm to pivot an indicator po
    Type: Grant
    Filed: September 11, 1987
    Date of Patent: June 27, 1989
    Assignee: Dwyer Instruments, Inc.
    Inventor: Steven O. Buchanan
  • Patent number: 4833919
    Abstract: Herein disclosed is a device for measuring a displacement of a movable member relative to a fixed member by putting the electromagnetic induction into practical use. The device comprises a first coil having first and second coil sections which are coaxially aligned along a common axis, a second coil arranged to establish a magnetic coupling with the first coil and extending along the common axis, and a short circuit ring arranged to establish a magnetic coupling with the first and second coils and movable relative to the same. The winding density of each of the first and second coil sections is gradually decreased from the outside end to the inside end thereof, and the winding density of the second coil is substantially even throughout the length of the same.
    Type: Grant
    Filed: November 23, 1987
    Date of Patent: May 30, 1989
    Assignee: Kanto Seiki Co., Ltd.
    Inventors: Yasuo Saito, Koichi Shimizu, Yuji Seki
  • Patent number: 4821570
    Abstract: The apparatus comprises a vertical elongate plunger (2) which is freely suspended by its top end from a thread (3) so as to be partially immersed in the liquid. A housing (1') mounted at the top of the recipient houses a pulley (4) capable of rotating through not more than one-fourth of a turn, said pulley serving to wind the plunger suspension thread and being fixed to a counterweight (5) so that the angular position of the pulley and counterweight assembly varies as a function of the depth of plunger immersion, and consequently as a function of the depth of liquid in the recipient. A mechanism is provided for measuring and digitizing the angular position of the pulley and includes, in particular, a code disk (11) outside the housing (1') and a magnetic coupling for transmitting motion from the pulley (4) to the code disk (11) through said housing.
    Type: Grant
    Filed: November 2, 1987
    Date of Patent: April 18, 1989
    Assignee: Materiel et Auxiliaire de Signalization et de Controle Pour L'Automation - Auxitrol
    Inventor: Danny J. Khoi
  • Patent number: 4821022
    Abstract: An apparatus for checking the workability of a float assembly used to determine the level of liquid in a vessel is disclosed and comprises: a float extension associated with the float of the float assembly and movable when the float assembly is in working order in response to the movement of the float caused by changing the level of liquid in the vessel; a sensor located in spaced relation to the float extension and acting to provide a signal when the float extension is in a predetermined position; and a checking system capable of being activated to move the foat extension into the predetermined position without regard to the level of liquid in the vessel when the float assembly is workable.
    Type: Grant
    Filed: April 4, 1988
    Date of Patent: April 11, 1989
    Inventor: Louis J. Jannotta
  • Patent number: 4796473
    Abstract: Disclosed is a system for sensing the level of a body of liquid within a container. The system includes a shaft secured parallel to a vertical axis of said container, said shaft having a magnetically responsive digital switch. Further provided is a toroidally-shaped reference element situated circumferentially about the shaft and secured at fixed level thereto, the reference element having a magnetic axis which is co-directional with the axis of the shaft. Also provided is a toroidally-shaped measuring sensing element also situated circumferentially about said shaft and vertically above said reference element but without securement thereto, said sensing element having a magnetic axis co-directional with the axis of said shaft and having a polarity of the magnetic axis which is repulsive in relationship to the magnetic axis of the reference element.
    Type: Grant
    Filed: May 4, 1987
    Date of Patent: January 10, 1989
    Assignee: Chem Tec Equipment Corp.
    Inventor: Craig S. Custer
  • Patent number: 4787253
    Abstract: A flow meter having electrical signal outputs and a digital display is described. A transducer uses a magnet inside the flow meter to position a ball on a resistor bar and a contact bar and, thus, generate a position signal. The position signal provides an accurate electrical indication of flow to the circuitry driving the display.
    Type: Grant
    Filed: June 29, 1987
    Date of Patent: November 29, 1988
    Assignees: Craig R. deFasselle, Robert J. deFasselle
    Inventors: Craig R. deFasselle, Robert J. deFasselle, David E. Kent
  • Patent number: 4771272
    Abstract: A liquid level electrical alarm apparatus includes a perforated hollow cylindrical sensor housing having upper and lower cup-shaped caps. A cylindrical float contained within the sensor housing contains a permanent magnet near its upper end, effective in closing the contact bars of a reed switch element mounted in the upper cap when the float rises a pre-determined level. The sensor body is suspended by a flexible electrical cable connected to the upper cap. Means are provided for adjusting the length of cable from which the sensor is suspended into a vessel, thereby permitting adjustment of the liquid level which trips the alarm.
    Type: Grant
    Filed: September 8, 1986
    Date of Patent: September 13, 1988
    Inventor: Arthur Barnes
  • Patent number: 4688587
    Abstract: The liquid tank comprises a container (1) containing a level gauge (3), an element (9) indicating the position of the gauge (3) and located outside the container (1), and a filling duct (2) for the container (1) fitted with an electro-magnetic sluice gate (10), a container (1) with a float (3) which modifies the resistance (9) as a function of its level. The value of the resistance (9) is monitored as a function of the time starting from the start of the filling operation so as to detect any fault inside the container (1).
    Type: Grant
    Filed: November 8, 1983
    Date of Patent: August 25, 1987
    Assignee: Compagnie Francaise d'Exploitation de Marques-Cofrem
    Inventor: Michel Bourgeon
  • Patent number: 4580450
    Abstract: The invention relates to a valve with a level gauge for a elongated liquidfied carbon dioxide container, comprising a body, and a level gauge having at least one articulating or flexible part between a float and a rod connected on the float to move an indicating member by a detecting member fixed thereon. The flexible part allows the float to contact the inner periphery of the container, wherein the inner periphery of the container shares a part of the weight of the float, cancelling the bending moment which is produced by the weight of the float and acting on the rod.
    Type: Grant
    Filed: May 17, 1985
    Date of Patent: April 8, 1986
    Assignee: Kabushiki Kaisha Neriki
    Inventors: Shiro Ota, Jiro Nitta, Teruo Hatori, Hajime Miyoshi, Akira Oi
  • Patent number: 4560986
    Abstract: This invention relates to a position indicator wherein the information on the location of a position-sensing target is obtained by measuring and comparing the ohmic resistances of two electric circuits including an arrangement comprising a pair of parallel conducting wires of high ohmic resistance and a sliding contact conductor slidable along the two parallel conducting wires while maintaining an electrically conductive contact to both conducting wires. The relative position of the position-sensing target kinematically linked to the sliding contact conductor intermediate two extremities of the pair of parallel conducting wires is obtained by measuring and comparing the ohmic resistance of the two circuits respectively including the sliding contact conductor and each of two halves of the two parallel conducting wires divided by the sliding contact conductor.
    Type: Grant
    Filed: January 16, 1984
    Date of Patent: December 24, 1985
    Inventors: Hyok S. Lew, Michael Stranahan