Immersible Electrode Type Patents (Class 73/304R)
  • Patent number: 6151963
    Abstract: An apparatus and method for wettability measurements are provided. The apparatus includes a surface having a pair of electrodes separated by an insulator affixed thereto. The electrodes are operable for supporting an oil film, and the may be immersed in a surfactant solution. Circuitry for measuring the complex impedance between the electrodes is coupled to the electrodes. The capacitive part of the complex impedance provides a measure of the oil thickness as it is removed by the surfactant solution. A rotating member is provided for agitating the surfactant solution thereby modifying the effectiveness of the solution in removing the film.
    Type: Grant
    Filed: August 24, 1998
    Date of Patent: November 28, 2000
    Assignee: Dresser Industries
    Inventor: Voldi E. Maki, Jr.
  • Patent number: 6148666
    Abstract: A liquid transfer device for an analysis unit includes a transfer needle having a tip, and a capacitive liquid level detector for detecting immersion of the tip of the needle into an analysis liquid by detecting a change in capacitance between a signal electrode and a counter electrode. The analysis liquid is contained in a vessel. The capacitive liquid level detector includes a signal electrode, a counter electrode, and a detection circuit connected to the signal electrode and the counter electrode. The detection circuit detects a change in capacitance between the signal electrode and the counter electrode. A temperature dependent detection resistor is disposed adjacent the tip of the liquid transfer needle. The tip of the liquid transfer needle and the temperature dependent detection resistor are movable into and out of the analysis liquid. The detection circuit includes a current supply for supplying current to the detection resistor.
    Type: Grant
    Filed: October 29, 1998
    Date of Patent: November 21, 2000
    Assignee: Boehringer Mannheim GmbH
    Inventor: Bernd Roesicke
  • Patent number: 6095178
    Abstract: A system for monitoring and controlling the level of liquid in a closed cainer includes a block for mounting at an upper end of the container, a lower level electrode for extending from the block vertically into the container, an upper level electrode for extending from the block vertically into the container and shorter than the lower level electrode, a valve for venting gas from the container, and a motor for driving the valve. Electric circuitry is responsive to liquid in the container rising to a free end of the upper level electrode to activate the motor to close the valve to increase gas pressure in the container to force lowering of the level of the liquid, and further electrical circuitry is responsive to the liquid in the container dropping below a free end of the lower level electrode to activate the motor to open the valve to vent the container and reduce gas pressure therein to permit rising of the liquid level.
    Type: Grant
    Filed: September 15, 1997
    Date of Patent: August 1, 2000
    Assignee: U.S. Army Corps of Engineers as represented by the Secretary of the Army
    Inventors: Paul A. Gilbert, Terry V. Jobe, Johnny Lee Morrow, Thomas Vertis McEwen
  • Patent number: 6086179
    Abstract: A pair of digital signals outputted from output ports of a CPU in opposite phase are applied to a pair of electrodes attached to an ink cartridge through inverters. A digital signal developed from the electrode connected to a resistor having a resistance value larger than or substantially equal to an ink resistance is inputted to a detection port through a hysteresis inverter. The CPU detects the presence/absence of ink in the cartridge, based on the phase relation of the digital signal applied through the hysteresis inverter with the digital signal outputted from the output port of the CPU or based on the presence/absence of the digital signal from the hysteresis inverter.
    Type: Grant
    Filed: October 1, 1997
    Date of Patent: July 11, 2000
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Motoshi Kishi
  • Patent number: 6082392
    Abstract: A hose assembly is provided for transmitting liquid fuel between the fuel tank of a highway truck and the fuel tank of an airport refueler. The assembly comprises inner and outer hoses. The inner hose transmits liquid fuel. A sealed passage is formed between the inner and outer hoses. Each end of the hose assembly is connected to a respective port for transferring the fuel between the highway truck fuel tank and airport refueler tank. The assembly includes at least one sensor port for connecting the passage to sensing means to detect leakage from the inner hose to the passage. A leakage sensing system is coupled to the sensor port for detecting leakage of fuel from the inner hose to the passage and for generating sensor signals. The leakage sensing system includes: (1) a pressure sensor for detecting a change in pressure within the passage, and (2) a liquid sensor for detecting the presence of liquid within the passage.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: July 4, 2000
    Assignee: General Transervice, Inc.
    Inventor: Robert Watkins, Jr.
  • Patent number: 6076399
    Abstract: A sewer basin has a tube mounted longitudinally in the basin to isolate the level sensing elements from particulate and non-soluble materials present in the basin which could contaminate the elements, which are used for selectively activating a pump in the basin. The liquid level in the tube is kept in equilibrium with the liquid outside of the tube by an aperture below the normal low liquid level. A filter is provided in the tube between the aperture and the level sensing elements. The filter is formed by a stack of filter elements mounted on an axial post extending into the tube from a bottom end cap. The elements are limited in their axial mobility on the axial post.
    Type: Grant
    Filed: October 30, 1997
    Date of Patent: June 20, 2000
    Assignee: Crane Pumps & Systems, Inc.
    Inventors: Dan G. Free, Mark Kowalak, Brian Mitsch
  • Patent number: 6065867
    Abstract: A method for measuring temperature and electrolyte level of a molten electrolysis bath in a cell for production of aluminum by electrolysis of alumina includes the steps of: (a) piercing the crust of a solidified bath with a crust breaker and immersing into the electrolyte, an extremity of a temperature probe to a sufficient depth until an initial temperature reading of at least 850.degree. C.
    Type: Grant
    Filed: December 11, 1995
    Date of Patent: May 23, 2000
    Assignee: Aluminium Pechiney
    Inventors: Benoit Sulmont, Pierre Homsi, Olivier Granacher
  • Patent number: 6065336
    Abstract: An oil level detector mounting arrangement, which includes a mount having a downward tube dipped in the oil in the oil tank of a vehicle, a float floating in the oil in the oil tank and moved along the downward tube, and a circuit board sealed in the downward tube and carrying a plurality of solenoids at different elevations for acting with magnets at the float to indicate the elevation of the float in the oil tank, wherein the solenoids each have a first end inserted through a respective hole at the circuit board and then welded to a contact at the circuit board, and a second end inserted through a respective hole at the circuit board and then welded to a common springy wire conductor suspended from the circuit board.
    Type: Grant
    Filed: June 29, 1999
    Date of Patent: May 23, 2000
    Inventor: Chung-Ho Liang
  • Patent number: 6062095
    Abstract: A dual compartment housing has a wiring compartment containing customer accessible wiring board and openings for a conduit connection. The wiring compartment is separated from an electronics compartment by a tunnel. The tunnel, which can be potted with a sealing compound, provides environmental and explosion proof protection for the electronics. An intrinsically safe barrier can be housed in the explosion proof wiring compartment, and the electronics compartment is then intrinsically safe. This relieves any constraint on separating the intrinsically safe electronics exposed to the process by an explosion proof boundary, and the process seal can be a "soft" seal. The housing is designed so that both compartments face the same direction.
    Type: Grant
    Filed: June 9, 1998
    Date of Patent: May 16, 2000
    Assignee: Magnetrol International
    Inventors: Michael J. Mulrooney, Boyce M. Carsella
  • Patent number: 6058776
    Abstract: The present invention is for a conductivity metering device. The invention is primarily for conductivity meters which are used for level gauging of fouled liquids where the fouling materials may cause functioning problems of the metering probe. The probe is intended for metering of the conductivity between the probe body 1 and a tube 14, made from metallic material, in order to determine if there is liquid inside the tube. The probe body 1 is the outer tip of a piston 6 and it may be made as one piece with the piston or as a separate part which is mounted onto the piston. The piston 6 and parts connected thereto are movably mounted in the cover part 15 and the cap 8 by sealing slide bearings 4, 7. When metering does not take place the tube 14 is mostly filled with water at a certain overpressure relative to its surroundings. As the metering piston 6 is kept retracted by an active overpressure between the sealings 4 and 7 liquid is prevented from leaking in.
    Type: Grant
    Filed: November 30, 1998
    Date of Patent: May 9, 2000
    Assignee: ABS Pump Production AB
    Inventors: Bengt Algers, Lars-Olof Eriksson, Leo Kotkaniemi
  • Patent number: 6040776
    Abstract: Described herein is an alarm system for use with a `bag-in-box` arrangement (10) which is used to collect effluent from a processing apparatus (20). The alarm system comprises a chamber (50) located between the processing apparatus (20) and the `bag-in-box` arrangement (10) which includes a level sensor (52) which indicates that the `bag-in-box` arrangement (10) has been overfilled by a predetermined amount and is ready for changing.
    Type: Grant
    Filed: April 16, 1996
    Date of Patent: March 21, 2000
    Assignee: Eastman Kodak Company
    Inventors: Edward Charles Glover, Martyn Stuart Glover
  • Patent number: 6026837
    Abstract: The present invention provides an automated chemical drain system which includes a buffer tank for collecting used chemical from a process machine, at least two level sensors in the buffer tank for sensing a fluid level and sending out a signal, a controller for receiving the signal from the level sensors and then sending out a second signal to a solenoid controlled valve when the first signal exceeds a threshold value, a solenoid controlled valve that is in fluid communication with the buffer tank and a collection tank, and a collection tank for collecting used chemical from the buffer tank. The collection tank may further be provided with a weight sensing device such that a signal may be sent out to the controller when the weight of the collection tank exceeds a maximum allowable value so that the controller shuts off the solenoid controlled valve to avoid overflow in the collection tank and to alert a maintenance operator to empty the collection tank.
    Type: Grant
    Filed: May 14, 1997
    Date of Patent: February 22, 2000
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventor: J. S. Chen
  • Patent number: 6023970
    Abstract: A disposable fluid level sensor is configured for determining the level of fluid in a container. A flex circuit or other electromagnetic sensor is coupled to a processing module having a power supply, the flex circuit being mounted at a selectable location by an adhesive patch which holds the sensor flush against the container. The processing module hangs from the sensor's antenna, and provides a human perceptible indication, such as a flashing light or an audible alarm, when the fluid level drops below a desired point as determined by the sensor. The sensor detects the change in fluid level by transmitting an electromagnetic signal and determining whether there is a change in reflected or resonated energy.
    Type: Grant
    Filed: April 2, 1997
    Date of Patent: February 15, 2000
    Inventor: David H. Blaine
  • Patent number: 6023971
    Abstract: A cross axis acceleration or roll angle insensitive angle sensor is constructed as a tubular body defining a closed tubular chamber with annular sensing plates soldered to each end. The tubular chamber is partially filled with partially electrically conductive liquid such that the resistance between the annular sensing plates and the tubular body is a function of the immersed area of the sensing plates. A variation in the inclination of the sensor causes a corresponding variation in the fluid level on the surface of the sensing plates and thus a variation in the electrical resistance between each sensing plate and the tubular body. The monitoring circuit for the angle sensor comprises a detecting means for sensing variations of the resistance between each sensing plate and provides an indication of any deviation from level position of the fluid within the tubular chamber.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: February 15, 2000
    Inventors: Harold L. Swartz, Jane E. Anderson
  • Patent number: 6006604
    Abstract: A method for determining an optimized solution of positions for N liquid surface sensors used to gauge quantity of liquid in the container, comprising the steps of:a) defining geometric limits of the container in terms of coordinates of a three axis (x,y,z) reference coordinate system assigned to the container;b) defining a chromosome structure for an individual, wherein said chromosome structure identifies a solution in terms of position data of the N sensors;c) determining a population of individuals wherein each individual in said population is a possible solution within said geometric limits; each individual having a respective chromosome; andd) executing a genetic algorithm on said population to identify a solution that meets a performance criteria as measured by a predetermined cost function.
    Type: Grant
    Filed: December 23, 1997
    Date of Patent: December 28, 1999
    Assignee: Simmonds Precision Products, Inc.
    Inventors: Luis Carlos Rabelo, Mark George Walker, Radoslaw Romuald Zakrzewski, Robert Curtis North
  • Patent number: 6008662
    Abstract: Conditions in a fluidized bed are measured with a probe and a circuit. The bed can be a polymerization reactor's reaction chamber, and the conditions can result in "sheeting" which is the build up of polymer on the chamber walls. The probe protrudes into the bed and detects a current which generally is a function of at least the impact and charge of particulates in the bed. The current detected by the probe is related to the conditions in the bed. The circuit measures the detected current. The probe has an inner probe piece of metallic material within an insulator of polymeric material. A portion of the insulator protrudes a first distance into the bed, and a portion of the inner probe piece protrudes a second distance into the bed. The first distance is less than or equal to the second distance. The insulator typically does not extend as far into the bed as the inner probe piece.
    Type: Grant
    Filed: October 31, 1996
    Date of Patent: December 28, 1999
    Assignee: Oxford Instruments America, Inc.
    Inventors: Robert E. Newton, David R. Day, Ron L. Swartzentruber
  • Patent number: 5992231
    Abstract: The invention relates to an apparatus for determining the condition of a fluid in a space, comprising: a measuring electrode extending inside the space; a second electrode placed in the space; and a measuring circuit for measuring the impedance between the measuring electrode and the second electrode and calculating the condition from the impedance, wherein the measuring electrode extends at least partially uncovered in the space.According to a preferred embodiment the apparatus is therefore provided with a measuring circuit which is adapted to measure the ohmic impedance between the measuring electrode and the auxiliary electrode. As stated, this provides the option of measuring the impedance of the substance present in the vessel so that with determined material properties it is possible to arrive at a better and more accurate measurement result.It is pointed out herein that the present electrode also enables determining of the capacity between electrode and second electrode.
    Type: Grant
    Filed: February 27, 1998
    Date of Patent: November 30, 1999
    Assignee: Meridian Instruments B.V.
    Inventors: Richard Mulder, Comelis W. P. Schoenmakers, Marian J. W. Slezak
  • Patent number: 5969620
    Abstract: A DC powered water/moisture monitor suitable for use in combination with a Christmas tree stand to detect a low water/moisture level is provided. The alarm device set forth has application in many other fields including farmland moisture monitoring, house plant, soil moisture monitoring, water tank level monitoring inter alia. The device includes an alarm, a casing, electronic circuitry and sensors/probes/electrodes for detecting moisture/water. The unit is an integral unit and combines all of these features in a one-piece waterproof assembly. The arrangement is, therefore, portable and can be readily employed in a variety of different environments.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: October 19, 1999
    Inventor: Pavel D. Okulov
  • Patent number: 5965814
    Abstract: An electrical circuit control system with multiple sensing probes used to detect the presence of excessive accumulations of moisture, in its liquid or frozen form in single or multiple phase air refrigerant systems. The electrical circuit control system will disengage the related electrical system when electrically alerted by the detecting sensors that an abnormal level of liquid or ice has occurred. The detecting sensors operate independently, therefore the control system will function properly with one sensor being utilized or with more than one sensor in place. Further, it utilizes multiple sensors, for detection, that are remote from the circuit control system and connected by electrically conductive leads at one end to the circuit control system and at the respective other end to the detection sensors. After the excessive accumulation of liquid or ice has been removed, the air refrigerant system will remain in an off position until reset by removing and reconnecting the main power source.
    Type: Grant
    Filed: October 21, 1997
    Date of Patent: October 12, 1999
    Inventors: Arnold E. French, Phillip M. Miller
  • Patent number: 5923102
    Abstract: An automatic sub-floor pumping system, having a controller box, sensor wires, suction hose and pump. Two or three sensor probes are used--the lowest, or ground, probe can be omitted, and the circuit referenced to earth or wiring ground. The pump evacuates water from beneath the basement floor through a hose inserted into a small hole drilled into the basement floor. The sensor probes can be simply wires with the last 1/8" to 1/2" bared, attached to the outside of the pump suction hose at two locations an inch or two apart. The hose, with wires attached, is inserted down the one-inch evacuation hole bored through the floor. The control uses a very low current on the wires, which are negative relative to ground so as to be cathodically protected from corrosion. An optional sensing circuit monitors lower probe wire voltage and warns of possible corrosion effects.
    Type: Grant
    Filed: April 20, 1998
    Date of Patent: July 13, 1999
    Assignee: Avcheck Corporation
    Inventors: Robert H. Koenig, Richard E. Koenig
  • Patent number: 5922941
    Abstract: A machine tool has a rotatably mounted part and a rotary leadthrough connected thereto, through which a fluid can be delivered to the rotatably mounted part. The rotary leadthrough further comprises an outlet from which leaking fluid emerges in the event of a leak in the rotary leadthrough. The outlet is connected to a fluid sensor which detects the emerging fluid and reports the leak.
    Type: Grant
    Filed: April 4, 1997
    Date of Patent: July 13, 1999
    Assignee: Chiron-Werke GmbH & Co. KG
    Inventors: Hans-Henning Winkler, Rudolf Haninger
  • Patent number: 5912617
    Abstract: A circuit for controlling the reserve lamp of a vehicle's fuel level indicator instrument. The circuit uses a switch controlled by an extremely asymmetric clock signal periodically to switch, for a very short time, the signal provided by the level sensor coupled to a comparator operable to compare this signal with a threshold value for the purpose of determining the state of the reserve lamp.
    Type: Grant
    Filed: September 15, 1997
    Date of Patent: June 15, 1999
    Assignees: SGS-Thomson Microelectronics S.r.l., Magneti Marelli S.p.A.
    Inventors: Vanni Poletto, Alberto Poma, Marco Morelli
  • Patent number: 5901740
    Abstract: A tank for holding a liquid for a predetermined and relatively long time in a continuous flow process. The tank includes an inner compartment with an inlet and an outer compartment with an outlet. The outer compartment encloses the inner compartment except its inlet. The liquid enters through the inlet and is forced upwardly in a non-preferential flow, it overflows to the outer compartment and comes out through the outlet. A pump is connected to the outlet and a variable throttle valve is in turn connected to the output of the pump. A level sensor for the liquid is connected to a computerized control unit to monitor the liquid level and to activate the throttle valve to either restrict or increase the flow to adjust the liquid level. Since the flow rate then is brought back to what it was when throttle valve is restricted to its original state, then changing the liquid level in the second compartment is equivalent to changing the holding time.
    Type: Grant
    Filed: October 31, 1997
    Date of Patent: May 11, 1999
    Inventor: Juan Andres Sanchelima
  • Patent number: 5898308
    Abstract: A device utilizes micropower, impulse radar and time domain reflectometry to determine the dielectric constant of a fluid. An electrically conductive probe preferably in the form of a transmission line, is inserted at least partially into the fluid. The device includes a signal generator that generates an impulse signal that is propagated along the probe. The time that it takes for the signal to reach the end of the probe is determined. The time of travel of the signal along the probe is then used to determine the dielectric constant of the fluid.
    Type: Grant
    Filed: September 26, 1997
    Date of Patent: April 27, 1999
    Assignee: Teleflex Incorporated
    Inventor: James R. Champion
  • Patent number: 5861811
    Abstract: A fluid sensor (100) senses a level of fluid (20) in a receptacle (10). The fluid sensor comprises a detector assembly (200) for detecting fluid and comprises sensor circuitry. The detector assembly comprises a detector body (201) comprising an electrically insulative material and defining first and second surfaces (210, 220) in a predetermined spaced relation. The detector body defines a space (250) between the first and second surfaces and defines a port (255, 257) for allowing fluid to pass in the space between the first and second surfaces. The detector assembly also comprises first and second conductive layers (212, 222) deposited over at least a portion of the first and second surfaces of the detector body, respectively. The sensor circuitry is conductively coupled to at least one of the first and second conductive layers for generating an electrical signal based on whether fluid is present in the space between the first and second surfaces.
    Type: Grant
    Filed: April 2, 1997
    Date of Patent: January 19, 1999
    Inventors: Benjamin N. Lease, Lee Paul Dollison
  • Patent number: 5856783
    Abstract: A pump control system which can distinguish between water and oil so that a pump can be controlled to pump water and deactivated before oil is pumped. Sensing is accomplished by a pair of capacitive sensors, one located above the other in a vessel in which water accumulates. A dual mode frequency oscillator is associated with each sensor. Each sensor reacts to the dielectric constant of the liquid at the sensor by changing its capacitance, to thus detect the presence of a conductive substance, such as a liquid, to cause the sensor's oscillator to switch its mode of oscillation. The dual mode oscillator of each sensor selectively generates a control signal having two different duty cycles. As the dielectric constant of the liquid medium is sensed, a logic circuit interposed between the sensors allows the output of each sensor to be turned off when only the lower sensor is in water. The circuit turns on the pump only when both sensors are in water and the pump remains on until both sensors are out of water.
    Type: Grant
    Filed: February 22, 1996
    Date of Patent: January 5, 1999
    Assignee: Raptor, Inc.
    Inventor: Robert F. Gibb
  • Patent number: 5835018
    Abstract: A low water level indicator includes a detection assembly and an indicator unit. The detection assembly comprises a housing, a pair of electrodes, a control unit, and a battery. The indicator unit comprises a light emitting diode (LED) and a base plate. The housing is preferably molded as two halves which are joined at assembly. An adjustment rod is held by a first and second snap retainer at substantially the bottom of the housing. The adjustment rod is used to adjust the height of the bottom of the housing relative to a water container. The electronic control circuit is mounted in a top cavity. A hook rod is held by a top spring clip which is disposed at substantially the top of the housing. The hook rod is used to provide stability for the placement of the detection assembly. When the water level in a water container is too low, electrical current will no longer pass from the first electrode to the second electrode through the water.
    Type: Grant
    Filed: July 24, 1997
    Date of Patent: November 10, 1998
    Inventors: Thomas C. Kursel, Robert E. Radke
  • Patent number: 5827474
    Abstract: Both an apparatus and method for measuring the depth of slag and molten metal contained in a tundish, ladle, electric furnace, or other vessel is provided. The apparatus includes a voltmeter for comparing the electrical potential of the steel, the slag-steel interface, and the air-slag interface to a ground potential, in combination with a probe member formed from a conductive material. The probe member has a proximal end that is electrically connected to the voltmeter, and a distal end movable between the vessel floor and one or the other of the interfaces. The apparatus further includes an articulated arm for positioning the distal end of the probe member in the vessel and across the molten metal so that it traverses at least one of the other two interfaces. The depth of the molten metal or slag is determined by noting differences in the electrical potential detected by the voltmeter while monitoring the vertical position of the distal end of the probe member in the vessel.
    Type: Grant
    Filed: January 2, 1997
    Date of Patent: October 27, 1998
    Assignee: Vesuvius Crucible Company
    Inventors: John D. Usher, Robin A. Sommers
  • Patent number: 5827985
    Abstract: A sensor apparatus is provided for transmitting electrical pulses from a signal line into and out of a vessel to measure a process variable. The sensor apparatus has a mounting section, at least one dielectric insert, a conductive transitioning pin, a metallic insert, a probe element, and an electrical connector to the signal line. The mounting section is configured to be coupled to the vessel and includes a central aperture with a first tapered surface. The dielectric insert has a second and third tapered surface. The second tapered surface is configured to engage the first tapered surface of the mounting section to prevent movement of the dielectric insert in a direction away from the mounting section. The conductive transitioning pin has a fourth tapered surface configured to engage the third tapered surface of the dielectric insert.
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: October 27, 1998
    Assignee: Endress + Hauser GmbH + Co.
    Inventors: Bernd D. Grieger, Donald D. Cummings
  • Patent number: 5811677
    Abstract: Apparatus for determining levels of immiscible fluids in a vessel that includes a transmission line sensor that extends vertically within the vessel for contact with fluids within the vessel. A generator is coupled to the sensor for transmitting along the sensor a first electrical signal that continuously sweeps a predetermined frequency range. A voltage detector is coupled to the sensor for providing a second electrical signal that varies as a function of the amplitude of electrical energy reflected at the sensor from the various electrical impedance discontinuities along the sensor, including particularly interfaces between and within immiscible fluids surrounding the sensor. The frequency spectral characteristics of the second electrical signal are analyzed to determine the spatial distribution of electrical impedance along the sensor, from which the levels of immiscible fluids within the vessel are determined.
    Type: Grant
    Filed: October 7, 1996
    Date of Patent: September 22, 1998
    Assignee: Bindicator Company
    Inventor: Thomas C. Cournanc
  • Patent number: 5793294
    Abstract: A galvanic cell is formed when ground water within a sump reservoir, tub or other pool, rises to contact electrodes constructed of dissimilar metals, the electrodes mounted in a bridge, with recessing, expansion brackets, to facilitate covering the sump hole and including an alarm device adapted to provide a warning signal should the water level exceed a predetermined level to contact the electrodes.
    Type: Grant
    Filed: September 18, 1995
    Date of Patent: August 11, 1998
    Inventor: Louis F. Schepka
  • Patent number: 5785142
    Abstract: A brake oil level safety device having a control circuit connected in series between the ignition system of a motor vehicle and the battery power supply thereof, the control circuit having a grounding conductor and two oil level detecting conductors mounted in the brake oil cup of the oil brake system of the motor vehicle to detect the level of brake oil in the brake oil cup, the control circuit being induced to turn on a yellow indicator light when the level of brake oil in the brake oil cup drops below the upper oil level detecting conductor above the lower oil level detecting conductor, or to turn on a red indictor light and cut off power supply from the ignition system when the level of brake oil in the brake oil cup drops below the upper oil level detecting conductor and the lower oil level detecting conductor.
    Type: Grant
    Filed: August 7, 1996
    Date of Patent: July 28, 1998
    Inventor: Chih-Chun Lo
  • Patent number: 5781019
    Abstract: A probe for use in time domain reflectometry includes a body having a conductive portion and an insulated portion. A conductive loop is provided having a first end and a second end. The first end is secured in the insulated portion of the body. The second end is secured in the conductive portion of the body, thereby shorting and grounding the conductive loop. An RF connector is provided for coupling the first end of the conductive loop to time domain reflectometry instrumentation.
    Type: Grant
    Filed: August 9, 1996
    Date of Patent: July 14, 1998
    Inventor: Bert Jan Telder
  • Patent number: 5780306
    Abstract: The invention relates to a system for mixing a liquid with another liquid or a solid material by blowing a gas onto the surface of the liquid. The invention further relates to a system for implementing said method. Gas is blown onto the surface of the liquid from a distance which can be adjusted by determining the level of the liquid. A system of the invention, hence, comprises a device for blowing a gas onto the surface of a liquid and a device for detecting the level of a liquid.
    Type: Grant
    Filed: November 7, 1996
    Date of Patent: July 14, 1998
    Assignee: Boehringer Mannheim GmbH
    Inventors: Hans Schels, Karl-Heinz Mann, Horst Menzler, Leonhard Geissler, Georg Kuffer
  • Patent number: 5777550
    Abstract: A high reliability instrument system includes means for applying a test condition to the instrument and for determining whether the instrument properly responds to the test condition, and means for inhibiting the generation of an instrument output in response to such testing. This provides verification that most of the instrument system components, but not the system output, are properly functioning. The system further includes means for overriding the output-inhibiting function when it is desired to test the entire instrument system including the system output. The instrument system may include a gap-type ultrasonic instrument, with the test condition comprising a pulse applied to one crystal, the effects of which are detected at the other crystal to determine sensor integrity. The system is preferably configured as a two-wire on-off instrument system, in which application of the test condition at a transmitter is controlled by signals applied to the two-wire signal loop at a remote receiver.
    Type: Grant
    Filed: January 3, 1997
    Date of Patent: July 7, 1998
    Assignee: Drexelbrook Controls, Inc.
    Inventors: Frederick L. Maltby, Glen L. Mitchell, Mort Gorowitz
  • Patent number: 5775164
    Abstract: A remaining liquid quantity detecting device to detect the quantity of the liquid remaining in a tank by applying a voltage to a pair of electrodes 1 and 2 set in the tank and detecting the electric resistance which will change under the influence of the liquid existing between the electrodes 1 and 2, wherein a standard voltage 10 having a predetermined electric potential is applied to both of the electrodes 1 and 2 at a non-detection time, and one electric potential between the electrodes 1 and 2 is changed so as to alternate on the basis of the standard voltage.
    Type: Grant
    Filed: November 6, 1996
    Date of Patent: July 7, 1998
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Motoshi Kishi
  • Patent number: 5749018
    Abstract: A method and apparatus for processing a photosensitive material. The apparatus includes at least one processing section and a replenishment system for delivering replenishment solution contained within a container to the processing section. The replenishment system including a single device for withdrawing replenishment solution from the container and for monitoring the level of the replenishment solution contained in the container. The container is made of a material that is electrically non-conductive. A pair of spaced electrically conductive members are provided within the container. One of the members has a passageway for allowing flow processing solution therethrough and one has a terminal end which extends below the other member within the container. An AC current is applied to the pair of spaced members and the AC current is monitored with a level sensing circuit.
    Type: Grant
    Filed: January 21, 1997
    Date of Patent: May 5, 1998
    Assignee: Eastman Kodak Company
    Inventors: Raymond E. Wess, Ralph L. Piccinino, Jr., John H. Rosenburgh
  • Patent number: 5744945
    Abstract: A method of measuring a cryogenic fluid level utilizing a high temperature ceramic superconductor material driven above its level of critical current density. A high temperature ceramic superconductor is placed in cryogenic fluid and a voltage is applied between two points on the superconductor. The voltage drop is then measured at a third point on the superconductor. This voltage drop corresponds to the change in cryogenic fluid level, and thus can be used to measure the fluid level. Sensitivity of the measurement is increased by driving the high temperature ceramic superconductor above its level of critical current density.
    Type: Grant
    Filed: November 8, 1994
    Date of Patent: April 28, 1998
    Assignee: Illinois Superconductor Corporation
    Inventors: James D. Hodge, Lori J. Klemptner, Justin Whitney
  • Patent number: 5731758
    Abstract: A toilet (6) has a solenoidal valve (1) in working relationship to a water-level probe (23), an overflow probe (25) and a floor-water probe (21) to prevent leaks reliably. A signal alarm (31) also is provided to warn of any problems and where they are in order to be able to repair them without the services of a professional plumber in many instances.
    Type: Grant
    Filed: May 1, 1997
    Date of Patent: March 24, 1998
    Inventors: Walter E. Suttlemyre, Vincent Albanese
  • Patent number: 5727421
    Abstract: An apparatus and method for providing liquid and gas proof sealing between a metal rod and a plastic housing molded there around. The rod includes a plurality of annular intrusions or protrusions along a length thereof. The plastic material is formed around the rod and the annular intrusions or protrusions. After the plastic material has cooled the rod is translated linearly with respect thereto whereby the annular intrusions or protrusions cause a cold flow movement or disruption of the plastic material. This movement results in a liquid and gas tight sealing between the rod and the plastic housing. The invention herein has particular application for liquid level sensing probes located within gas pressurized vessels. In such examples the rod or rods are used for sensing liquid level by means of electrical conductivity with the sensed liquid.
    Type: Grant
    Filed: February 10, 1995
    Date of Patent: March 17, 1998
    Assignee: IMI Cornelius Inc.
    Inventor: George W. Murphy
  • Patent number: 5729206
    Abstract: A ground water alert device includes an elongated water proof cable member which has a predetermined length and is inserted into a water level monitoring pipe of a well for a predetermined depth above a water table, a cable housing for delivering and collecting the cable member, a water sensor such as a probe which is electrically connected to a free end of the cable member for lowering into the monitoring pipe to the predetermined depth above the water table, a DC power source, a control circuitry electrically connected between the DC power source and the cable member for generating alert signals when the water sensor detects water, a depth indicator having a plurality of length scales uniformly provided along the cable member to indicate the length of the cable member from the water sensor, and a cable supporter for securing the cable member in place at a top end of the monitoring pipe so as to ensure the predetermined length of the cable member retaining in the monitoring pipe.
    Type: Grant
    Filed: January 17, 1997
    Date of Patent: March 17, 1998
    Inventor: Gary H. Divens
  • Patent number: 5719332
    Abstract: A process and a system for operating a level sensor, particularly for measuring amounts of liquid in motor vehicles, employs a plurality of heatable thermistors wherein a number of the thermistors are covered by liquid depending on the level of the liquid, and are cooled below a breakpoint temperature of the thermistors. The total resistance of the thermistors, which may be connected with further resistors, changes discontinuously as a function of the liquid level. At least one thermistor is located above the maximum possible level. The temperature of the thermistors is increased to such an extent by a feeding of electrical heating power that all thermistors which are above the existing level exceed their breakpoint temperatures, whereupon the total resistance is measured.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: February 17, 1998
    Assignee: VDO Adolf Schindling AG
    Inventor: Werner Wallrafen
  • Patent number: 5719556
    Abstract: A liquid level detecting system for detecting a conducting liquid level in a non conductive container which utilizes a grounding rod mounted in a lower portion of the container and a conductive sensing rod mounted at a position above the grounding rod. An oscillator is provided having a frequency in the range of about 600 hertz to about 100 kilohertz. The output of the oscillator is applied to the sensing rod through a high impedance circuit and a high pass filter. In another embodiment, the high pass filter may have the higher end frequencies attenuated to produce a band pass filter which selectively passes the frequency of the oscillator. The voltage drop across the circuit which includes the conductive sensing rod to ground is detected by a voltage peak detector and a threshold detector to produce an output which detects the drops in voltage when the conductive fluid level in the tank rises so that both the sensing rod and the grounding rod are covered, completing the circuit.
    Type: Grant
    Filed: February 11, 1997
    Date of Patent: February 17, 1998
    Inventors: Robert Albin, John A. Cacciola
  • Patent number: 5717337
    Abstract: Time-domain reflectometry based measuring systems which include transmission lines having an inner conductor and a ground conductor, a pulse generator generating pulses on the transmission line, and a pulse circuit producing oscillation pulses from pulse reflections caused by disturbances, such as a material interface, within the transmission line. The oscillation pulses induce subsequent transmission line pulses, beneficially using sing-around. A peak detector detecting the peak amplitude of the reflections and producing a trip-point voltage for the pulse circuit may be included. Transmission lines having a wound inner conductor and one or more switched taps which are selectively shorted to the ground conductor may be used. The system oscillates with pulses at frequencies which depend upon the state of the switches. Those frequencies (or periods) can be resolved into a parameter which depends upon the position of a transmission line disturbance.
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: February 10, 1998
    Inventor: John M. Kelly
  • Patent number: 5694974
    Abstract: A fluid level detection system (50) for ink in a printing press (10) having a vessel (58) having walls (60) defining a chamber (62), an elongated rotatable shaft (64) in the chamber (62), a motor (66) for rotating the shaft (64), an elongated flexible blade (68) affixed to the shaft 64 such that the motor (66) rotates the blade (68), and a proximity sensor (72) adjacent the walls (60) of the vessel (58) to detect the rotating blade (68) in the absence of ink at the level of the blade (68), with the blade (68) flexing in the presence of ink such that the sensor (72) does not detect the blade (68).
    Type: Grant
    Filed: January 24, 1996
    Date of Patent: December 9, 1997
    Assignee: Goss Graphic Systems, Inc.
    Inventors: Thaddeus A. Niemiro, Frederick J. Whiting, John W. Manser, Joseph Vucko, Frank R. Czajka
  • Patent number: 5678114
    Abstract: An automatic photographic developing apparatus for photosensitive materials includes a number of processing baths which are filled with processing solutions of different types for processing silver halide coated photosensitive materials. A same number of solution tanks communicated with the respective processing baths are provided for supplying the processing solutions, produced by dissolving solid agents, to the respective processing baths. A level sensor is installed in each of the solution tanks which monitors the level of the processing solution in the respective solution tanks. A plurality of shield members are provided, each shield member surrounding and protecting a respective one of the level sensors, and each shield member being detachably mounted to its respective level sensor. Each of the shield members includes a plurality of split members which are separable from each other and which are connectable to each other to surround the respective level sensor.
    Type: Grant
    Filed: June 9, 1995
    Date of Patent: October 14, 1997
    Assignee: Noritsu Koki Co., Ltd.
    Inventors: Hidemitsu Eko, Haruo Hakamada, Hideo Ishii
  • Patent number: 5669263
    Abstract: In the presence of a defect in the insulation cover of known probes, liquid medium can leak from the container into the interior space of the housing of the probe, and from there into the surrounding environment, and endanger or even injure persons present there. The probe housing has an interior space with two chambers. The first chamber, which is close to the container, is capable of withstanding the pressure prevailing in the container. A passage opening present between the first chamber and the second chamber for the sensor electrode, or for its electrical conductor, is closed by a movable closing part or a stationary closing element. In the event of leakage through the insulation cover, the pressure would be transmitted from the container into the first chamber, but could not propagate from there into the second chamber and on from there.
    Type: Grant
    Filed: February 15, 1996
    Date of Patent: September 23, 1997
    Assignee: Gestra Aktiengesellschaft
    Inventors: Kerstin Borchers, Joachim-Christian Politt, Holger Schroter
  • Patent number: 5668536
    Abstract: An apparatus for sensing the level of fluid, including a two electrode device being disposed in the fluid and a microprocessor. The microprocessor being connected to the two electrode device and delivering alternating current thereto. The microprocessor reads the voltage across the device, compares the voltage to a predetermined voltage level, and produces a warning signal in response to the fluid level being below a predetermined fluid level.
    Type: Grant
    Filed: April 16, 1996
    Date of Patent: September 16, 1997
    Assignee: Caterpillar Inc.
    Inventors: Paul C. Gottshall, Timothy A. Boston, Kevin D. Ehrenhardt
  • Patent number: 5661251
    Abstract: A sensor apparatus is provided for transmitting electrical pulses from a signal line into a vessel to measure a process parameter. The sensor apparatus includes a lower flange configured to be coupled to the vessel. The lower flange is formed to include a central aperture defined by a radially outwardly tapered surface located adjacent a top surface of the lower flange. The apparatus also includes a conductive probe element including a head having first and second radially outwardly tapered surfaces and an elongated conductive portion extending away from the head. The first tapered surface of the head is configured to engage the tapered surface of the lower flange to prevent movement of the probe element in a direction toward the lower flange. The apparatus further includes an upper flange configured to be coupled to the lower flange to secure the probe element to the lower flange.
    Type: Grant
    Filed: December 19, 1995
    Date of Patent: August 26, 1997
    Assignee: Endress + Hauser GmbH + Co.
    Inventors: Donald D. Cummings, Gerd Wartmann, Kenneth L. Perdue
  • Patent number: 5661405
    Abstract: An elongate, flexible sensor for sensing an electrically conductive liquid, such as water, has two flexible electrodes extending along the sensor and two flexible sleeves extending therealong and being attached adhesively to each other along the sensor. Each electrode is a ribbon made from a carbon-filled, silicone rubber material. Each sleeve extends around an associated one of the electrodes and is braided from a filamentary, polyester material so as to define multiple apertures enabling such a liquid reaching the sensor to pass through the sleeves so as to cause a short circuit between the electrodes.
    Type: Grant
    Filed: November 6, 1995
    Date of Patent: August 26, 1997
    Inventors: Jay S. Simon, Morris Simon