Magnet Patents (Class 200/84C)
  • Patent number: 6069331
    Abstract: The invention is directed to a flow control vertical switch for starting and stopping electric pump motors and being controlled by the level of a liquid using the flow of the liquid being moved to hold the switch in a switched position until the sump is depleted. The invention consists of a collar, a shaft rotatably mounted on the collar, a float arm having a magnet and a float mounted on the collar and a switch housing affixed on the collar above the magnet. A flow arm mounted on the shaft and located in the stream flow retains the magnet in switching position until the fluid stops running.
    Type: Grant
    Filed: April 22, 1999
    Date of Patent: May 30, 2000
    Inventor: Gene H. Utke
  • Patent number: 5886312
    Abstract: A liquid level sensor for a tank includes coaxial inner and outer tubes having lower ends extending into the tank and upper ends projecting from the tank, with the upper end of the inner tube projecting from the outer tube and disposed a known distance from the top of the tank. A switch assembly includes a switch disposed in the inner tube and operable in response to proximity to a switch actuator which is carried by a float encircling the outer tube and movable therealong with the liquid level, the switch being connected across a pair of electrical conductors extending from the upper end of the inner tube. An indicator strip extends lengthwise of the conductors and is held thereagainst by a transparent sleeve, the strip having indicia indicating distance to the switch. Plastic cable ties extend through openings in the inner tube and snugly hold the switch assembly against the inner tube to permit manual axial movement of the switch assembly while preventing inadvertent movement thereof.
    Type: Grant
    Filed: September 25, 1997
    Date of Patent: March 23, 1999
    Assignee: Midland Manufacturing Corp.
    Inventors: Gaston C. Barmore, Jr., Joseph C. Fiore, Norman A. Magiera, Robert H. Dean, Jerzy Drazkowicz, Carl J. Campagna, Ralph G. Portis
  • Patent number: 5880423
    Abstract: A water level sensor includes a magnetic tube and a float disposed on a vertical oval rod portion of the magnetic tube. A magnetic switch is contained in the magnetic tube and connected with a power cord. The float has a center hole for the vertical oval bar to extend therein, an inner annular wall extending down to define the center hole with an outer annular wall, and an open lower end closed with a cap. And a magnetic ring is fixed around the center hole on an upper surface of the float. When the float moves down to a preset lower level in water of a tank, the magnetic ring and the magnetic switch produce induction to turn off the power to prevent the tank from burning owing to no water therein.
    Type: Grant
    Filed: August 8, 1997
    Date of Patent: March 9, 1999
    Inventor: Jui-Yang Li
  • 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: 5827962
    Abstract: A fluid level indicator for a brake fluid reservoir is disclosed which comprises a socket and circuit board which, once assembled, are installed within a chamber integrally molded with the fluid reservoir. The circuit board is assembled to the socket, which is in turn attached to an instrument panel warning device. In an alternative embodiment, the circuit board is formed integrally with connector pins, and injection molded about to form a socket assembly. The assembly is then attached to the instrument panel and installed within the chamber.
    Type: Grant
    Filed: September 12, 1996
    Date of Patent: October 27, 1998
    Assignee: ITT Automotive Inc.
    Inventors: Stefan Guenther, Kevin J. Gallagher
  • Patent number: 5775877
    Abstract: An electric submersible motor-driven pump includes a pump housing (2) in which is located a pump motor (3) and an associated impeller (4). A separate detachable float and switch housing (6) is detachably connected to the pump housing (2) and defines a substantially elongated upright chamber having a longitudinal axis in which an elongated float (8) moves for operating a switch arm of a switch whose electrical components are isolated from the fluid being pumped. A switchable adapter plug exteriorly of the housings is rendered operative by the electrical components upon movement of the float (8) to selectively energize or de-energize the pump motor (3).
    Type: Grant
    Filed: February 26, 1996
    Date of Patent: July 7, 1998
    Assignee: ABS Pumps, Ltd.
    Inventor: Otto Genz
  • Patent number: 5711354
    Abstract: A highly reliable digital level sensor assembly is provided to replace optical and capacitance type sensors in high purity chemical delivery systems. The digital level sensor assembly is particularly useful in bulk chemical refill delivery systems for high purity chemicals employing a manifold that ensures contamination free operation and canister change outs with a minimum of valves and tubing.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 27, 1998
    Assignee: Advanced Delivery & Chemical Systems, Inc.
    Inventors: Stephen H. Siegele, Craig M. Noah, John N. Gregg
  • Patent number: 5607002
    Abstract: A highly reliable digital level sensor assembly is provided to replace optical and capacitance type sensors in high purity chemical delivery systems. The digital level sensor assembly is particularly useful in bulk chemical refill delivery systems for high purity chemicals employing a manifold that ensures contamination free operation and canister change outs with a minimum of valves and tubing.
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: March 4, 1997
    Assignee: Advanced Delivery & Chemical Systems, Inc.
    Inventors: Stephen H. Siegele, Craig M. Noah, John N. Gregg
  • Patent number: 5581062
    Abstract: A side-mountable liquid level sensor utilizes a rubber sealing grommet to temporarily hold the buoyant member within the cylinder of the liquid container opening to facilitate assembly. The buoyant member has an open slot with cooperating limit structure on the buoyant member and sensor rod to facilitate manufacture.
    Type: Grant
    Filed: August 17, 1993
    Date of Patent: December 3, 1996
    Assignee: Standex International Corporation
    Inventor: Edward Gomez, Jr.
  • Patent number: 5562423
    Abstract: An automatic control for a liquid pump which assures that the pump starts when the liquid reaches a predetermined level and that the pump is stopped when the level has fallen to a second predetermined level. The control includes a permanent magnet mounted in a float which is contained within a float chamber and which has a bottom opening through which liquid can enter the float chamber. A top portion of the float chamber is provided with a one-way valve which allows air to escape from the float chamber but which prevents air from entering the float chamber so that when the float moves up with the liquid, the magnet actuates a magnetic responsive switch such as a reed switch to cause the motor to drive the pump. As the pump lowers the level of the liquid, the level of the liquid in the float chamber does not fall because of the partial vacuum within the top of the float chamber and the magnetic holds the switch closed so as to maintain energization of the pump.
    Type: Grant
    Filed: October 17, 1994
    Date of Patent: October 8, 1996
    Assignee: Johnson Pumps of America, Inc.
    Inventors: Stephen R. Orth, Burton L. Siegal
  • Patent number: 5485866
    Abstract: A valve to monitor the level of fluid in an above ground storage tank while the tank is being filled, cutoff the flow of fluid when the tank is in a full condition, and as long as the filling pressure is on the valve the valve will remain cutoff even if the fluid level in the tank has lowered. A relief valve to drain the fluid remaining in the filling hose after the filling pressure is off. A sight level indicator to visually show that the tank is in a filled condition. A monitoring node to be used with or without the mechanical cutoff valve in a totally controlled application where the filling person is not responsible for shutting off the filling tank truck, with two switches, one to alert that the tank is near a filled condition and the second to alert that the tank is in a filled condition.
    Type: Grant
    Filed: April 13, 1995
    Date of Patent: January 23, 1996
    Inventor: James H. Bowen
  • 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: 5427137
    Abstract: A valve to monitor the level of fluid in an above ground storage tank while the tank is being filled, cutoff the flow of fluid when the tank is in a full condition, and as long as the filling pressure is on the valve the valve will remain cutoff even if the fluid level in the tank has lowered. A relief valve to drain the fluid remaining in the filling hose after the filling pressure is off. A sight level indicator to visually show that the tank is in a filled condition. A monitoring node to be used with or without the mechanical cutoff valve in a totally controlled application where the filling person is not responsible for shutting off the filling tank truck, with two switches, one to alert that the tank is near a filled condition and the second to alert that the tank is in a filled condition.
    Type: Grant
    Filed: December 15, 1993
    Date of Patent: June 27, 1995
    Inventor: James H. Bowen
  • Patent number: 5426271
    Abstract: A liquid level sensor is provided with a single piece pivotable device which is used to move a permanent magnet into and out of the detection zone of a magnetically sensitive component, such as a Hall effect element. The pivotable device comprises a buoyant portion, a magnet holding portion and a pivot portion with arms connecting the pivot portion to the buoyant portion and the magnet holding portion. The pivot portion of the pivotable device is shaped to be received over a fixed post attached to a container. The injection gate of the mold used to form the pivotable device is advantageously located so that the pressures throughout the mold cavity are positive to the action of the foaming agent to result in the buoyant portion of the pivotable device having a significantly lower density than the other portions of the pivotable device. This variable density in a single piece device permits a smaller overall size to be used without sacrificing the sensitivity needed to detect changes in a liquid level.
    Type: Grant
    Filed: January 18, 1994
    Date of Patent: June 20, 1995
    Assignee: Honeywell Inc.
    Inventors: Richard A. Clark, Brad L. Cummins, Timothy K. Erickson, Brian D. Mc Bride, Gary R. O'Brien
  • Patent number: 5410913
    Abstract: For liquid-level sensing in a tank, the invention provides a tank-mounted first subassembly that is adapted for suspension of a vertical guide from the top of the tank, such that a guided float may coact with an elongate vertical ribbon, to angularly displace a magnetic element carried by the upper end of the ribbon. The tank-mounting of this first subassembly completes closure of the tank and its contents, and closure structure of this first subassembly assures containment of the ribbon and its magnetic element within the closed volume of the tank. A second subassembly of magnetically responsive electrical means is encapsulated by a housing which is detachably connectable to the closure structure of the first assembly, solely by access that is external to the closed tank. Electrical output of the second subassembly is flexibly available to remote indicating and/or monitoring circuitry which forms no part of the invention.
    Type: Grant
    Filed: December 15, 1993
    Date of Patent: May 2, 1995
    Assignee: Thomas G. Faria Corporation
    Inventor: David A. Blackburn
  • Patent number: 5374790
    Abstract: A liquid level switch assembly is provided which can be adjusted as to what liquid level will actuate the switch. A support bracket is mountable to the tank and a float arm is pivotally mounted to the support bracket inside the tank by way of a pivot axle. A magnet is mounted to the pivot axle such that the magnet rotates as the float arm pivots to follow the liquid level on the tank but such that the angular position of the poles of the magnet can be adjusted relative to the float arm when the float arm is retained as the magnet is rotated. A reed switch is mounted on the support bracket near the magnet such that when the float arm is in a predetermined range of angular position relative to the horizontal, the reed switch is actuated by the magnet.
    Type: Grant
    Filed: February 5, 1993
    Date of Patent: December 20, 1994
    Assignee: Rochester Gauges, Inc.
    Inventor: Agoston Horvath
  • 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: 5340281
    Abstract: A protective device for a water-pump apparatus includes an upright hollow tubular member which is mounted on a top end of a pump unit of the water-pump apparatus, the interior of the tubular member communicating with an interior of the pump unit. A floating switch actuator is provided movably inside the tubular member and floats inside the tubular member in response to water level therein. The switch actuator is provided with a permanent magnet. A control unit is mounted on an outer surface of the tubular member and is connected electrically to a motor unit of the water-pump apparatus. The control unit includes a magnetically actuated switch which is activated by the switch actuator when the switch actuator is at a predetermined position inside the tubular member. The control unit cuts off power supply to the motor unit when the switch actuator ceases to float inside the tubular member.
    Type: Grant
    Filed: February 2, 1993
    Date of Patent: August 23, 1994
    Inventor: Pai-Tzeng Su
  • Patent number: 5324171
    Abstract: A pump assembly having a hermetically sealed switch cavity for retaining a magnetically actuated mechanical switch. The assembly includes a housing having a motor cavity and an integral guide for cooperating with an external float assembly. A housing cover includes electrically conductive pins extending therethrough and is connected to the housing to substantially seal the motor cavity. A switch cover cooperatively engages a portion of the housing cover to form the hermetically sealed switch cavity. The switch cavity also encloses at least one conductive pin in the housing cover.
    Type: Grant
    Filed: May 14, 1993
    Date of Patent: June 28, 1994
    Assignee: Liberty Pumps
    Inventor: Charles E. Cook
  • Patent number: 5305639
    Abstract: A liquid petroleum gas (LPG) gauge sensor unit fits between the units of an existing magnetically-coupled LPG gauge and includes a magnetic field sensing switch, a mechanism to variably position the switch and an intermediate magnet. The intermediate magnet is positioned upon an axle-like mechanism upon which it is free to rotate and magnetically couples to the existing gauge base magnet which is, in turn, connected to a float that measures the liquid level. The existing indicator magnet in the gauge assembly magnetically couples with the intermediate magnet so that the gauge unit visually indicates the level of LPG within the LPG tank, despite the increased distance between the base and indicator magnets caused by the sensor unit. The magnetic field sensing switch is used to sense the position of the base or intermediate magnet and thereby sense the liquid level.
    Type: Grant
    Filed: October 16, 1992
    Date of Patent: April 26, 1994
    Assignee: Scully Signal Company
    Inventor: Robert A. Pontefract
  • Patent number: 5304852
    Abstract: A fluid drop detecting reservoir tank has a float with a magnet which moves down in accordance with a drop in the level of fluid in a reservoir tank. The magnet closes a magnetically operated switch when the fluid reaches a predetermined level so that a predetermined drop in the level of the fluid is detected. The fluid drop detecting reservoir tank is provided with a mount casing for receiving therein a switch casing in which the switch is encased. The reservoir tank is provided with a retainer mechanism arranged between the mount casing and the switch casing for holding the switch casing in the mount casing so as to locate the switch below the magnet and preventing the switch casing from being withdrawn from the mount casing.
    Type: Grant
    Filed: April 30, 1992
    Date of Patent: April 19, 1994
    Assignee: Tokico Ltd.
    Inventors: Reiji Hiraga, Yoshihiro Nakamura
  • Patent number: 5297939
    Abstract: An automatic control for a liquid pump which assures that the pump starts pumping when the liquid reaches a predetermined level and the pump is stopped when the level has fallen to a second predetermined level. The control includes a permanent magnet mounted in a float that is contained within a float chamber and which has a bottom opening through which the liquid can enter the float chamber. A top portion of the float chamber is provided with a one-way valve so as to allow air to escape from the float chamber, but which prevents air from entering the float chamber such that when the float moves up with the liquid, the magnet actuates a magnetic responsive switch such as a reed switch to cause the motor to start to drive the pump. As the pump lowers the level of the liquid, the level of the liquid in the float chamber does not fall because of the partial vacuum within the top of the float chamber and, thus, the magnet continues to energize the pump.
    Type: Grant
    Filed: February 1, 1993
    Date of Patent: March 29, 1994
    Assignee: Johnson Pumps of America, Inc.
    Inventors: Stephen R. Orth, Burton L. Siegal
  • Patent number: 5294917
    Abstract: A float-operated switch assembly is mounted in an opening in the top of a tank. It includes a vertical non-magnetic pipe having a pair of floats normally hanging beside it. Each of the floats has a magnet thereon normally in a position proximate the pipe when the float is down. A magnetic field between this magnet and a switch operator support magnet inside the pipe normally holds the latter magnet in a set position. The floats are located at a height such that, when the liquid has risen to the desired upper limit, the rising liquid has caused the floats to swing up and outward from the pipe, pulling their respective magnets out of supporting relationship to the switch operator support magnet whereupon the support magnet drops and a switch is operated for activating a signal circuit. A manual test knob is provided to remotely, manually lift the floats.
    Type: Grant
    Filed: April 6, 1992
    Date of Patent: March 15, 1994
    Inventor: Larry C. Wilkins
  • Patent number: 5262604
    Abstract: This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel.
    Type: Grant
    Filed: April 5, 1991
    Date of Patent: November 16, 1993
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: James G. Powell
  • Patent number: 5254815
    Abstract: A reservoir tank according to the present invention is comprised of a tank body storing an amount of operating fluid, connected to a specific device for supplying thereinto the operating fluid and having a bottom with a hole isolated from the operating fluid; a float movable in the vertical direction according to the variation of the liquid level of the operating fluid; a magnet secured to a lower end of the float; and a reed switch unit assembly having a reed switch with a pair of terminals, a pair of conducting elements connected to the pair of terminals of the reed switch, a connector casing, and a pair of connectors each of which is secured to one end of the connector casing in such a manner that each connector is electrically connected to the respective conducting element.
    Type: Grant
    Filed: April 24, 1992
    Date of Patent: October 19, 1993
    Assignee: Aisin Seiki Kabushiki Kaisha
    Inventors: Toshihiro Nakano, Shinji Sakata
  • Patent number: 5239285
    Abstract: A low salt level sensor comprising a float within a brine tank, apparatus for detecting whether the float has risen in response to the addition of a predetermined amount of water to the brine tank to a height such that an adequate supply of salt is present in said brine tank and apparatus for indicating if the float has not risen high enough. A method of detecting whether the salt level is low in the brine tank of a water treatment system is also described. According to this method, brine is removed from the brine tank and a predetermined amount of water is added. A determination is then made as to whether the brine level has reached a height such that an adequate supply of salt is present in the brine tank and an indication is provided if the brine level is below this height.
    Type: Grant
    Filed: September 21, 1990
    Date of Patent: August 24, 1993
    Assignee: Culligan International Company
    Inventor: Stanley F. Rak
  • Patent number: 5224379
    Abstract: A gauge for indicating whether the level of a liquid, such as fuel or oil, in a tank has reached one or more preselected levels. A magnet is mounted in a stem attached atop a float which moves up and down with the rising and falling of the liquid level. When the magnet is adjacent an electrical switch housed in a sealed cover, the switch closes and connects an external power supply to a warning light. The float moves within a cylinder which has a small drain hole at the bottom and a vent near the top. Liquid moves into and out of the guide through the drain hole at a relatively slow rate and thereby eliminates intermittent closing and opening of the switch which would otherwise occur due to the sloshing of the liquid when the tank is in motion, such as when mounted in a vehicle.
    Type: Grant
    Filed: October 14, 1992
    Date of Patent: July 6, 1993
    Assignee: The Kelch Corporation
    Inventors: Ronald E. Koebernik, Michael J. Holz
  • Patent number: 5189726
    Abstract: The apparatus comprises a boiler (2) provided with an electric resistance heating element (3) arranged to heat and vaporize water, a water reservoir (6) independent of the boiler and a pump (8) designed to transfer water from the reservoir to the boiler. In the boiler a predetermined amount of water substantially corresponding to 50% of the overall capacity of the boiler itself is kept constant, thereby maintaining the steam amount unaltered and making the steam use always immediate. A steam control valve connected to the boiler (2) is driven by a magnetic float switch (14) housed in the water reservoir (6) to stop the steam emission when the cold water reservoir (6) is empty.
    Type: Grant
    Filed: March 1, 1991
    Date of Patent: February 23, 1993
    Assignee: CTS Costruzioni Techniche Sanmarinesi
    Inventor: Costanzo Pan
  • Patent number: 5159305
    Abstract: A variable differential switching apparatus comprising first structure for forming first and second magnetic fields presented sequentially along a travel path, the first field being stronger than the second field; and second structure, including a field responsive element, presented for relative travel along the path in opposite directions, the element and fields and travel path characterized in that as the element encounters the first field during relative travel in one of the directions in unlatched condition, the element is displaced by the first field into a latched condition, and as the element encounters the second field, it remains in the latched condition, and as the element continues to relatively travel in the first direction beyond the second field, it returns to unlatched condition; the element and fields further characterized in that as the element travels oppositely along the travel path, it remains in unlatched condition as the element encounters the second field, and thereafter as the element
    Type: Grant
    Filed: January 15, 1992
    Date of Patent: October 27, 1992
    Assignee: Harwil Corporation
    Inventor: Harold D. Hutchinson
  • 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: 5154079
    Abstract: A remote indicator attachment kit for use with the mechanical level gauge of an oil tank located in the basement area of a dwelling, to indicate at a remote point the drop in oil level, comprises a magnet attachable to the movable member of the existing mechanical gauge, and a reed switch and mounting that is attachable to the see-through housing of the mechanical gauge, to be influenced by the magnet on the movable member. Circuitry connected to the reed switch and to the remote indicator is energized to provide an indication at the remote point.
    Type: Grant
    Filed: September 30, 1991
    Date of Patent: October 13, 1992
    Inventor: Peter A. Lupoli
  • Patent number: 5155311
    Abstract: A magnetically actuated float switch assembly for use with a submersible pump, comprises a float rod with two spaced stops, a movable float carried by the rod which moves between the stops in response to fluid level, the rod being mounted in a vertical oriented position for movement upwardly and downwardly in response to float movement against the two spaced stops, a magnetic body carried at the upper end of the rod for movement therewith, a generally U-shaped magnetic follower element with two spaced, magnetically responsive arms on one side of the magnetic body, or two sets of arms disposed on either side of the magnetic body to provide a dual U-shaped arrangement, the follower element being rotatably mounted with the arms thereof in a generally horizontal position, one above the other for movement of the arms thereof upwardly and downwardly in a vertical plane, the arms and magnetic body being positioned relative to each other so as to dispose the magnetic body for movement from arm to arm to thereby allow
    Type: Grant
    Filed: July 3, 1991
    Date of Patent: October 13, 1992
    Assignee: S.J. Electro Systems, Inc.
    Inventor: Gene Utke
  • 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: 5090212
    Abstract: A cutoff switch for refrigerant recovery storage container will indicate when the storage container reaches a maximum safe level. The switch will disable the compressor to prevent further recovery of refrigerant. The switch is located in a sensor housing that couples to a magnet housing. The magnet housing mounts to the upper end of the storage container and connects with the float. A magnet will move vertically in response to movement of the float. At least one Hall Effect sensor mounts in the sensor housing. The Hall Effect sensor will sense the presence of the magnet and disable the compressor accordingly.
    Type: Grant
    Filed: December 17, 1990
    Date of Patent: February 25, 1992
    Assignee: Technical Chemical Company
    Inventors: Robert L. Keltner, Jim B. Ferguson
  • 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: 5042300
    Abstract: A self-aligning oil level sensing switch is provided with an elongated float shaped to pass freely through a threaded aperture in the side of an engine crankcase as a switch housing is screwed into the aperture. The float is free to rotate about one end of a mounting rod, and is unsymmetrical about its center of mass such that it is automatically aligned by gravity into its intended operating position, regardless of the final rotative position of the switch housing. The mounting rod is pivotally and rotatably mounted on the switch housing and has an opposite end provided with a counterweight which is unsymmetrical and is free to rotate with the rod. A magnetically actuated switch mechanism includes a spring-biased magnet enclosed in a conductive sleeve which is electrically coupled to a first connector pin. The sleeve is positioned within an electrically-conductive, magnetically-transparent cover member electrically coupled to a second connector pin.
    Type: Grant
    Filed: November 22, 1989
    Date of Patent: August 27, 1991
    Assignee: Kelsey-Hayes Company
    Inventors: Robert P. Benjey, Paul C. Weiner
  • Patent number: 5041812
    Abstract: A reservoir, provided with a device for warning when the level of an operation fluid to be supplied to a fluid pressure master cylinder drops below a given level, comprises a fluid tank for storage of the operation fluid and a float chamber with an upper wall provided on the side portion of the fluid tank. A reed switch for the fluid level drop warning device is provided at the lower portion of the float chamber, and a float having a magnet is retained in the float chamber. A partition for restricting the movement of the float is detachably mounted at the communicating section between the fluid tank and float chamber. This arrangement facilitates the mounting and replacement of the float and reed switch.
    Type: Grant
    Filed: May 10, 1990
    Date of Patent: August 20, 1991
    Assignee: Nissin Kogyo Kabushiki Kaisha
    Inventors: Hidenori Misaizu, Shinichi Okada
  • Patent number: 5031405
    Abstract: In a hydraulic reservoir of a master cylinder for vehicle including: a main body having an internal space for storing brake fluid; a float provided with permanent magnet, so arranged as to be vertically movable in the internal space of the main body; a reed switch attached to the outside surface of the main body, the reed switch being actuated by magnetic force of the permanent magnet, when the float with permanent magnet is positioned under a predetermined level; and a hollow for attaching the reed switch to the outside surface of the main body, the reed switch is supported by a support member in the hollow, a rubber bush is tightly and elastically fitted to the inside wall of the hollow and a fixing member is so fitted to the hollow as to push the rubber bush to the support means, terminals of the reed switch being inserted tightly through holes of the rubber bush whereby the reed switch is held in the hollow.
    Type: Grant
    Filed: December 5, 1989
    Date of Patent: July 16, 1991
    Assignee: Nippon Air Brake Company, Ltd.
    Inventors: Toshiyuki Takahashi, Ichiro Ishiwata
  • Patent number: 5030803
    Abstract: A device for use as a float switch device for use in a liquid medium is disclosed which has a magnetic latching feature used to produce an offset, with the switch actuating in a first manner when the liquid level drops to a first level, and actuating in a second manner when the liquid level rises to a second level which is aabove the first level by a selected offset distance. The float element has two buoyant disks on the ends of a hollow cylinder, with switching magnets being located intermediate the two buoyant disks, and latch magnets being located on the bottom of the bottom buoyant disk. The float element slides vertically on a switch stem having a magnetic reed switch therein and a steel washer on the bottom thereof, with the float element being latched in a downward position by the latch magnets until the liquid level rises to the level of the upper buoyant disk, resulting in crisp and precise operation of the switching function.
    Type: Grant
    Filed: August 7, 1989
    Date of Patent: July 9, 1991
    Assignee: General Dynamics Corp., Air Defense Systems Div.
    Inventor: Charles J. Yarbrough
  • Patent number: 5026954
    Abstract: A liquid level response electrical switch assembly responsive to the level of a monitored liquid is shown as having a body and a chamber-like or containment portion, electrical conductors are carried by the body for connection to as associated electrical load, a reed switch is carried by and within the body for opening and closing an electrical circuit through the electrical conductors, and a magnet positioned by a buoyant float responsive to the level of the monitored liquid is effective for actuating the reed switch.
    Type: Grant
    Filed: October 16, 1989
    Date of Patent: June 25, 1991
    Assignee: Hi-Stat Manufacturing Co., Inc.
    Inventor: David J. Cebulski
  • Patent number: 5025827
    Abstract: A fluid level controller flexibly set up according to the number of level steps to be controlled and the pitch between such level steps, which comprises a plurality of joint pipes connected in series to form a pipe assembly; a ring-shaped magnetic floating member sleeved on such a pipe assembly to follow fluid level to move up and down; a plurality of reed elements having each a reed switch connected in series with one another and received in the joint pipes; a main control circuit comprising latching relays in quantity one less than the quantity of the reed elements and a plurality of controlled actuators respectively connected to the reed elements.
    Type: Grant
    Filed: April 12, 1990
    Date of Patent: June 25, 1991
    Inventor: Evans Weng
  • Patent number: 5017748
    Abstract: A float switch includes a buoyant housing defining a non-linear guide path. Switch operating means is located displaceably under gravity within the guide path. The switch operating means is operable to activate switch means in at least one position along its path when the housing is tilted.
    Type: Grant
    Filed: July 31, 1989
    Date of Patent: May 21, 1991
    Inventor: Andrew J. Sapiro
  • 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: 4965555
    Abstract: In a device for monitoring the liquid level in a tank, utilizing a reed switch projecting into the tank in an internally cylindrical hollow rod and a float provided with a permanent magnet and guided on the hollow rod, the reed switch is constructed as an independent exchangeable part introducible into the hollow rod with an accurate fit and with a small assembly outlay. The slide-in part has three radially resilient abutment zones distributed uniformly around the circumference. In order to accurately introduce the slide-in part into the hollow rod, with a minimum of force, three axial guide grooves associated with the resilient abutment zones are formed radially outwards in the inner envelope surface of the hollow rod. In order to achieve the final accurate fit, the slide-in part, introduced completely into the hollow rod, is rotated until the resilient abutment zones are located in regions between the guide grooves of the hollow rod.
    Type: Grant
    Filed: August 21, 1989
    Date of Patent: October 23, 1990
    Assignee: Daimler-Benz Aktiengesellschaft
    Inventors: Michael Huttenberger, Wolfgang Kleineberg, Hans Schaal, Thomas Attinger, Jurgen Dietz
  • Patent number: 4962370
    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.
    Type: Grant
    Filed: April 25, 1989
    Date of Patent: October 9, 1990
    Inventor: John Borriello
  • Patent number: 4959997
    Abstract: A magnetic float for a magnetic sensor wherein magnetized magnetic powder is dispersed into a foamed synthetic resin, and the magnetic flux thereof acts on a reed switch in the magnetic sensor to turn on or off the reed switch. The magnetic powder is substantially wholly coated with the synthetic resin.
    Type: Grant
    Filed: June 8, 1989
    Date of Patent: October 2, 1990
    Assignee: Ishikawa Tekko Kabushiki Kaisha
    Inventors: Junzo Aisa, Mituo Yamamoto
  • Patent number: 4955231
    Abstract: A liquid float gage assembly for a fluid reservoir includes magnet containing float in a vertical tube having an adjacent vertically spaced reed switch arrangement. The float is capsule shaped with an extended round cylindrical portion having rounded axial ends; and the magnet tends to be attracted to the closest reed switch to bias the float against the inner surface of the tube. The tube has a horizontally cross-sectional shape substantially matching and just larger than an axial section of the float so that the float has a stable floating orientation with a horizontal axis and is capable of rolling during vertical movement within the tube to reduce friction due to liquid surface tension between the float and the tube. The magnet has poles at axially opposing ends thereof within the float and a circumferentially consistent spacing relative to the outer surface of the float so as to provide a substantially non-varying magnetic field strength radially adjacent the float as the float rolls.
    Type: Grant
    Filed: May 12, 1989
    Date of Patent: September 11, 1990
    Assignee: General Motors Corporation
    Inventor: Christopher J. Mahoney
  • Patent number: 4943210
    Abstract: A control system for a pump includes a level sensor switch that is positioned along a production string in an oil well shaft. The level sensor switch is protected from damage by inner and outer housings. A control circuit responsive to the level sensor switch is also provided. The control circuit includes an adjustable timer that is located at ground level remote from the harsh environment of the oil well shaft. The timer controls the operation time of the pump during each pumping cycle.
    Type: Grant
    Filed: February 7, 1989
    Date of Patent: July 24, 1990
    Inventors: James R. Bailey, Jr., Jean D. Ashcraft
  • Patent number: 4942274
    Abstract: An improved ball controlled float control unit wherein a slotted raceway housing pivotally accomodates a narrow ball cage within the slot and with the ball cage being in constant contact with said ball while the ball is permitted to be rollingly supported by the edges defining the slot, with the ball being precluded from getting out of or behind the ball cage, thereby eliminating any possibility of the ball locking up the control function of the unit.
    Type: Grant
    Filed: June 21, 1988
    Date of Patent: July 17, 1990
    Assignee: Expert Corporation
    Inventors: Richard Riback, Eric Will