Abstract: An eyeglass lens processing apparatus for processing a periphery of an eyeglass lens, includes: a processing chamber in which a lens processing tool is disposed, the processing chamber having a drainage port; a water supply unit which supplies water for lens processing to an interior of the processing chamber; a drainpipe connected to the drainage port; a sensor which detects an amount of the water within the processing chamber or the drainpipe; and a controller which controls the water supply unit based on a result of detection by the sensor.

Abstract: A sensor and associated circuitry for sensing and reacting to the presence of a fluid or other material having heat capacity. A positive-temperature-coefficient device initiates a switching step when the amount of heat-capacity material reaches a certain level, or is totally absent. The switching step may trigger an alarm or control circuit to rectify the fluid level.

Abstract: An animal drinking apparatus and method which automatically alerts an animal caretaker to low liquid level conditions in a fluid or liquid vessel is disclosed. A standard type of animal drinking vessel can be fitted with a sensing device. A receiving device and one or both of an audible device and a visual device can provide one or more alert signals when the sensing device indicates that a low level fluid condition has occurred in the drinking vessel. The sensing device and the receiving device may be separable for remote operation and a low level transmission signal may be sent via wire, radio frequency, infrared frequency, fiber optics, or in any known manner.

Abstract: A volume measurement system uses volume element counting in determining the amount of a liquid such as fuel in an irregularly-shaped container such as a fuel tank which can have changing orientation. The container is conceptually divided up into a plurality of volume elements. An orientation sensor determines the orientation of the container or of the liquid surface, which is approximated as a plane. A computational or optical processor uses orientation data to project vectors representing the volume elements onto a direction normal to the liquid interface plane. These projected distances are then arithmetically or optically compared to the location of the liquid interface plane.

Abstract: An apparatus 100 for providing information concerning a condition of a vessel such as a steam drum 12 which segregates steam and liquid from one another includes a liquid contact assembly 102, a signal generator element 130, and a housing 112 and a conduit 114 for enclosing the signal generator element 130 in a substantially leak proof manner within the vessel space. The liquid contact assembly 102 is disposable at a first vessel location in the steam drum 12 and has a vibration component 108 operable to vibrate at natural frequencies which vary as a function of a predetermined characteristic of the liquid at the first vessel location and a support component 110 for supporting the water contact assembly 102 in contact with the liquid at the first vessel location. The signal generator element 130 generates a signal indicative of a natural frequency of the vibration component 108.

Abstract: A leakage response system for an appliance includes a leakage sensor which is operative to change an electrical parameter upon contact by a conductive liquid, a controller circuit electrically coupled with the strip for generating an activation signal in response to contact of the strip by a conductive liquid and a response device coupled with the controller circuit and activated by the signal. The sensor includes a mat which is constructed of top and bottom outer layers of electrically conductive fabric separated by a central nonconductive fabric layer; and a pair of fusing layers fusing the top and bottom layers to the central nonconductive layer. The sensor may also include a pair of conductive pins for installation into a surface for detecting moisture hidden within the surface. The response device may include an audible alarm and/or a valve for shutting off the water flow in the appliance water supply line.

Abstract: A motion sensor having an outer tubular member closed at both ends thereof and an inner tubular member, concentrically disposed within the outer tubular member, forming therein an inner chamber and with the outer tubular member forming an outer chamber surrounding the inner chamber, the inner tubular member being provided with one or more apertures in walls thereof allowing fluid flow between the inner and outer chambers. A liquid at least partially fills the inner and outer chambers providing a liquid interface therein. Operatively connected to at least one of the tubular members are devices for determining the position of the liquid interface of the liquid.

Abstract: An apparatus 100 for providing information concerning a condition of a vessel such as a steam drum 12 which segregates steam and liquid from one another includes a liquid contact assembly 102, a signal generator element 130, and a housing 112 and a conduit 114 for enclosing the signal generator element 130 in a substantially leak proof manner within the vessel space. The liquid contact assembly 102 is disposable at a first vessel location in the steam drum 12 and has a vibration component 108 operable to vibrate at natural frequencies which vary as a function of a predetermined characteristic of the liquid at the first vessel location and a support component 110 for supporting the water contact assembly 102 in contact with the liquid at the first vessel location. The signal generator element 130 generates a signal indicative of a natural frequency of the vibration component 108.

Abstract: A method for measuring fluid level uses data sensed by an oil level sensor to determine the level of oil in a motor vehicle oil pan. The oil level sensor can include a receiver tube oriented upright in the oil pan of the vehicle. A level tube is disposed in the receiver tube and below the level tube is a reference tube. A circuit is electrically connected to the tubes for outputting a signal representative of oil level in the oil pan. As the engine oil level decreases within the level tube, the output of the sensor drops. The method includes providing a series of signals to the sensor and recording the output from the sensor with the sensor in a variety of configurations. This information is then processed to determine the ratio of measured oil in the oil pan to the proper operating oil level.

Abstract: Apparatus 1 for detecting a change of flow rate of a fluid being pumped through a pipe 2, the apparatus 1 comprises a cylindrical chamber 4, a fluid sensor 6 disposed on the side of the chamber 4, alarm means 8 and a vent valve 10 located at a distal enclosed end of the chamber 4. The chamber 4 extends upwardly from the pipe 2 and is formed with a port 4 at the lowermost end of the chamber 4. The lower end of the chamber 4 is formed with a port 7 that extends through the wall of the pipe 2 such that the inner region of the chamber 4 is in fluid communication with the pipe 2 via the port 7. The fluid sensor 6 may be a solid state liquid level switch such as an optical liquid level switch. It will be appreciated that other types of fluid level sensors may be used. The fluid sensor 6 is in communication with the alarm means.

Abstract: An electronic control unit includes a first microprocessor monitoring the operation of a second microprocessor and has a monitoring operation blocking unit for preventing the second microprocessor from being reset by the first microprocessor while the second microprocessor is loading from a memory thereof so that even when a control program is loaded into the monitoring microprocessor before one is loaded into the monitored microprocessor, the control program can be loaded with certainty. Each microprocessor executes a control program stored in the memory, and when a predetermined reloading condition has been established, executes a loading process for receiving load data transmitted thereto from outside into the memory.

Abstract: A sensor for detecting the level of circulating fluid in a tank comprises a paddle blade disposed at a particular height and oriented generally radially from a rotating shaft in the tank. A sensing device, such as a strain gauge, is attached to the paddle blade to detect when the paddle blade is in at least one of a normal and a displaced position, thereby indicating that fluid is absent or present at a particular level. Additional sensors may be used in the same tank to provide fluid level feedback at more than one height.

Abstract: A liquid level indicator apparatus provides direct readout of liquid level at high resolution using an array of vertically disposed Hall-effect magnetic switches. To overcome the limit to closer spacing of the switches imposed by their vertical dimension, they a disposed side by side horizontally and vertically by a distance less than the vertical dimension of each switch. They are mounted on a flat flexible substrate and then bent around into a hollow cylinder or prism shape. A floating magnet of annular shape surrounds the cylinder, or a magnet corresponding to the cylindrical or prismatic shape floats inside the surrounding circuit board. Several circuits are shown for displaying a liquid level readout resulting from the actuation of the switches by the magnet.

Abstract: The present invention relates to a device for measuring the filling level of a filing material in a container, having a sensor and a control/evaluation unit. The invention provides a device which permits optimized determination of the filling level and/or the monitoring of the filling level in a container. For this purpose a sensor is designed such that it is operated in conjunction with at least two different measurement methods and/or the sensor is operated in at least two different operating modes, that the control/evaluation unit operates the sensor respectively according to at least one of the two measurement methods and/or at least in one of the two operating modes, and that the control/evaluation unit determines the filling level of the filling material in the container with the aid of the measured data of the sensor, which are supplied via at least one measurement method and/or during at least one operating mode.

Abstract: Acoustic level sensing by creating, or failing to create, resonance in a tube having a free end. An acoustic transducer at one end of the tube injects sound at a frequency that could produce resonance, depending on whether the free end is open or closed. The drive to the acoustic transducer is then removed, and the sound decay in the tube is monitored to determine if resonance occurred. Based on that determination, a signal is produced that indicates whether a material has or has not closed the free end of the tube. Beneficially, the same acoustic transducer that produces the sound monitors the sound decay. To determine whether resonance has occurred, or to verify system operation, the sound decay at the possible resonant frequency can be compared to the decay at another frequency. Temperature compensation can be performed by attempting to produce resonance at a plurality of frequencies.

Abstract: A reed switch unit 44 for detecting a liquid level of a reservoir tank 30 of a master cylinder includes a reed switch 11, including a contact portion 14 sealed in a glass tube 16, and reed portions 18 extending respectively from opposite ends of the glass tube 16 in a direction of an axis thereof. The reed switch unit further includes a unit main body 45 including terminals 50 which support the reed portions 18 and 18, respectively, in electrically-connected relation thereto to fix the reed switch 11. The reed switch 11 is fixed to the unit main body 45 in such a manner that the glass tube 16 is disposed in non-contact relation to the unit main body 45.

Abstract: A dry fire protection system for a spa and the spa's associated equipment. A heating element heats the spa's water. A resistive water level sensor senses that the level of water around the heating element is higher than a predetermined height or lower than a predetermined height, and a heating element deactivation device electrically deactivates the heating element when the water level around the heating element falls below a predetermined level. In a preferred embodiment, the heating element deactivation device is an electric circuit comprising a comparator circuit and a control circuit.

Abstract: A method and a device for determining the amount of ink or similar liquid existing in a container are disclosed. A resonance circuit is arranged on the container storing the liquid. A voltage having a preselected frequency is applied to a drive coil located outside of the container to thereby induce a voltage having a preselected frequency in the resonance circuit. The voltage induced in the resonance circuit, in turn, induces a voltage having a preselected frequency in a sense coil also located outside of the container. The amount of liquid in the container is determined in terms of the voltage induced in the sense coil.

Abstract: The present invention comprises a remote marine monitoring and control system that compiles security information and statistics for on-board equipment on unattended boats, uses a wireless transmitter to send this data to a user over a communications network and allows a user to remotely operate the user's boat in response. Boat operational data can be provided to a user on a variety of personal communication devices and/or through a monitoring web site. These devices can also be used by the user to send a user command to remotely control the operation of the boat. The remote marine monitoring system identifies normal operating conditions for on-board equipment and compares these conditions to current operating activity in order to detect unusual activity. Security information can also be compiled and reported relating to intrusion sensors, keyless entry and the boat's physical location.

Abstract: The present invention provides an automatic monitor for use in a tank with a water soluble softening agent. The monitor includes a signal emitter that produces a signal capable of being detected by an array of signal-detecting sensors. The sensors are displaced generally vertically in the brine tank from the minimum depth of the softening agent to the maximum depth of the softening agent. An output is produced in response to said signal. The monitor also includes an electronic device for receiving and interpreting the output and determining if a low softening agent condition is present as the supply of the softening agent is depleted. An indicator warns when a low softening agent condition is present. Preferably, the sensors are linearly spaced within the tank.

Abstract: Disclosure is made of a housing and electric connection panel for sump pump and full septic tank alarm apparatus which includes an electric connection panel with a female receptacle and electrical terminal strip mounted on the panel and power lines leading onto the panel, and this electric connection panel mounted in grooves in a panel housing, and this panel housing attached to a sump tank by a connector pipe nipple extending through the side wall of the panel housing and through the side wall of the septic tank and electric wire leads to from the sump pump float switch, sump pump, and full tank alarm each of which is in the sump tank and the electric leads extending through the connector pipe nipple and into the panel housing and the piggy back male plug of the sump pump switch plugged into the female receptacle on the electrical panel and the male plug of the sump pump plugged into the piggy back of the sump pump switch, and the electric power supply to the electrical connector panel entering through the b

Abstract: A method and apparatus for monitoring the fluid level in a well bore to limit fluid drawdown in the well bore to a maximum set level. The user first determines the static water level in the well bore by lowering a sensor into the well bore. The sensor is configured to sense when it makes contact with water, so that the user can be made aware that the sensor has reached the static water level. The user then lowers the sensor to a maximum desired drawdown level. The sensor is then set to sense when it loses contact with the water. The sensor is then monitored to determine if the fluid had has dropped below the maximum desired drawdown level, and an audible and/or visual alarm alerts the user whenever the maximum desired drawdown level is exceeded.

Abstract: A system is provided for monitoring the status of a water softener at a remote location. The system includes a water softener controller with a control processing unit for determining the status of the water softener. The system also includes a water softener transmitter and a water softener indicator. The transmitter is coupled to the controller and transmits the status of the water softener to the indicator. The water softener indicator receives and displays the status message. The system is capable of determining whether the water softener is operating normally, whether the salt level is low or whether the water softener needs servicing.

Abstract: A drain alert device for detecting an overflow condition in a drainage system having a drain conduit, wherein wastewater is received through an inlet of the drain conduit, is provided, comprising an overflow conduit extending horizontally from the drain conduit below the inlet. The overflow conduit leads to an overflow detection device which includes a vessel having an internal volume sufficient to contain an amount of overflow wastewater. A buoyant member having an elongated, substantially vertical, overflow indicator resides within the vessel, and the overflow indicator is guided by a guide tube extending above the vessel. Thus, the overflow indicator reveals the extent of an overflow condition by protruding through the guide tube in response to the level of wastewater within the vessel. The vessel further includes a drain port having a threaded coupling capable of receiving a conventional flexible hose so that the appliance may be operated despite obstructions in the drain conduit.

Abstract: A safety switch that can be used with an air handling system is disclosed. The air-cooling system includes a drain pan for collecting liquid condensed on the evaporator coils. The pan is fluidwise connected to a T- or L-shaped tubular structure, installable at any slope from horizontal to vertical, in which the switch is mounted and the switch is electrically connected to a circuit of the system, a power circuit or an alarm circuit. The switch has an annular float containing an annular magnet mounted about a tube in which is sealed a reed switch. The float ascends or descends based on the level of liquid within the tubular structure. Dependent upon a predetermined level of liquid within the tubular structure the float will move along the tube to open or close the reed switch to either disrupt operation of the air handling system or operate an alarm circuit.

Abstract: A propane level monitor assembly for determining the level of propane in a storage tank. The propane level monitor assembly includes a gauge monitor assembly including a housing being adapted to be removably mounted upon a propane tank gauge, and also including a transmitter being disposed in the housing; and further includes a receiver unit including a housing member and also a receiver member being disposed in the housing member for receiving waves transmitted by the transmitter.

Abstract: A method of analyzing heat and mass transfer in gas-liquid two-phase flow in an object transfer system includes dividing the object heat transfer system into a plurality of nodes, calculating a void fraction in a gaseous phase above a liquid surface of a node and calculating a void fraction in another node beneath the first node, and calculating a liquid surface level based on the results of the previous steps.

Abstract: A water-monitoring apparatus includes a frame installed by water. A reel is mounted on the frame. A cable including lower and upper ends is wound on the reel. A buoy is connected with the cable. At least one sensor is used to detect a water quality parameter and to produce a signal representative of the water quality parameter. The at least one sensor is carried via the buoy and electrically connected with the lower end of the cable. The reel can be rotated to adjust a length of the cable extending from the reel so that the at least one sensor can always be immersed in the water. A signal relay includes a first block electrically connected with the at least one sensor and a second block electrically connected with a monitoring station wherein the first and second blocks are connected with each other in a non-contact electric manner.

Abstract: A liquid level gauge for use on a vehicle indicates a liquid level in a start-up and in a running state in accordance with requirements designated by a user of the vehicle, the level being indicated with little or no time lag. Data detected in analog form by a fuel sensor is converted to digital signals by a sensor value reader. An indicator driver receives time signals from a timer and speed signals from a vehicle speed sensor and, in a suitably timed manner reflecting the vehicle speed, calculates fuel level data to be indicated based on the digital signals. The fuel level data thus calculated is indicated on a fuel level indicator. The fuel level data may be updated at intervals of one second if vehicle speed is less than 4 km/h and at intervals of 15 seconds if vehicle speed is at least 4 km/h.

Abstract: An optical device for measuring a level of a fluid in a container wherein a light conducting body having a top surface and a bottom surface is positioned within the container and into the fluid. A first end of the light conducting body and an oppositely disposed second end, preferably having stepped end surfaces, reflect and refract light in a predetermined manner based upon the fluid level in the container. A resulting brightness of the top surface is therefore inversely proportional to the level of the fluid. Such an optical device is particularly suited toward application to a vehicle fuel tank.

Abstract: A control system for maintaining the liquid levels in a plurality of reservoirs connected in series includes a parenthetical control module and one or more nested control modules. The parenthetical control module includes a proportional only level controller in electrical communication with the level sensor of said last reservoir (VOUT) in the series and is adapted to produce an output signal that becomes a set point for one or more PID flow controllers controlling the inflow (FIN) into the first reservoir (V1) in the series. The nested control module, one for each reservoir upstream of said last reservoir (VOUT), includes a proportional only level controller in electrical communication with the respective level sensor of each respective upstream reservoir and is adapted to produce an output that becomes a set point for one or more PID flow controllers adapted to control the respective outflows of said respective upstream reservoirs.

Abstract: A fuel-level indicator for a motor vehicle fuel tank includes an insulating base carrier; an electrically conducting slide track mounted on the base carrier and containing at least one metal; and a movable transmitter arm carrying a slide contact and being in sliding engagement with the slide track. The slide track is free from silver.

Abstract: The present invention 10 discloses a safety stand for a tree 18 having a main housing body 20 and attached thereto a secondary housing body 32. The main housing 20 is elliptically shaped having situated thereon illumination lights 26, LED lights 36 along with transparent picture sleeves 38. Also attached thereto is a mounting collar 28 with threaded screws 30 for receiving and holding a tree trunk along having an electrical outlet 34 disposed thereon. The main housing 20 also contains a CD player 24 along with a water reservoir 62 for watering the tree. Also contained on the main housing 20 is an extinguisher system having flame sensors 76 attached thereto in the form of decorative ornamental bulbs 12 placed throughout the tree. Vent holes 70 are provided in the bulbs 12 through which air can pass in the form of smoke so as to activate the sensors 76 and thereby having a bulb transmitter 78 send a signal to a means for an alarm 46 disposed in the main housing body.

Abstract: A sump alarm system which includes a sensor, carried by a sensor housing, the sensor being operatively connected to an alarm circuit, carried in an alarm circuit enclosure, the alarm circuit configured to output an alarm signal when the sensor senses a predetermined alarm condition.

Abstract: A bath overflow plumbing fitting has a housing having a connecting portion for mating with a complementary connecting portion of a plumbing component of the bath overflow so as to attach the plumbing fitting and plumbing component to a bath and to provide an overflow passageway through the housing into the plumbing component. The fitting is arranged to detect the presence of water in the housing and provide an alarm output in response to such detection, so as to provide a bath alarm that is part of the overflow plumbing, rather than an attachment to it. This facilitates the production of a rugged alarm that does not significantly impede the flow of water through the overflow.

Abstract: A water leak detection apparatus comprises a sensor, a control unit and a valve module. The sensor is adapted to be placed below a water line or coupling. The valve module is positioned as far upstream on a water line as possible. The control unit actuates the valve module and an audible alarm when the sensor detects a water leak. The valve module closes a valve positioned along the water line to restrict flow through the water line until the control unit has been manually reset. The control unit also features a trigger button to allow the valve to be manually cycled for cleaning, for instance.

Abstract: A sensor monitoring system comprises a passive sensor, a monitored transmitter, a repeater, and a central receiver. The system provides easy installation, convenient calibration, and very low maintenance. The sensor and the monitored transmitter are battery powered and, in order the conserve battery power, the sensor and the monitored transmitter receive power only on command from their respective microprocessor.

Abstract: The device for monitoring the storage level of a product contained in a tank includes a device for measuring the storage level of the product, a central processing unit for utilizing the level read off by the measurement device, a memory for holding at least one storage level threshold, a device for comparing a level value output by the central processing unit with the threshold, a device for triggering a restocking command and controlled by the comparison device, and a device for transmitting the restocking command to a restocking center. It furthermore includes a device for receiving at least one time of information which is issued by the restocking center in response to the transmission of the restocking command.

Abstract: An automatic infusion-monitoring instrument includes a clip adapted to clamp a flow-indicating cylinder of an infusion set corresponding to a liquid level in the cylinder that keeps unchanged when there is sufficient amount of infusion liquid in the infusion set, a floater pre-disposed in the flow-indicating cylinder to move upward and downward along with the liquid level in the flow-indicating cylinder, a detecting unit having an emitter and a receiver mounted in the clip to normally face the floater, and an alarm unit electrically connected to the detecting unit via a conducting wire. When the liquid level in the flow-indicating cylinder lowers so that the floater is moved to locate below the emitter and the receiver and no longer blocks the wave emitted by the emitter, the alarm unit is actuated to emit sound, voice, light or flash as a warning signal of running-out infusion liquid.

Abstract: A fluid sensing system for monitoring a fluid parameter within a fluid container includes a fluid sensor and a fluid receiver. The fluid sensor is positioned at a first location and is operable to sense the fluid parameter. The fluid receiver is positioned at a second location remote from the first location and within proximity to the fluid sensor. The fluid receiver includes an amplifier having a feedback path. The amplifier is in a waiting non-oscillating mode when the fluid sensor is not electromagnetically coupled to the fluid receiver and in an active oscillating mode when the fluid sensor is electromagnetically coupled to the fluid receiver, such that feedback in the feedback path is one of either a substantially zero feedback and a negative feedback when the amplifier is a waiting non-oscillating mode and said feedback path is a positive feedback when said amplifier is in an active oscillating mode.

Abstract: A fluid level sensor for a fluid tank of a marine vessel is provided. The sensor includes a sensor mount and further includes a circuit housing that is pivotally connected to the mount to pivot about a predetermined pivot axis. A float assembly is configured to supply an actuating angle substantially impervious to fluid tank tilt and/or fluid splash at least along an axis generally perpendicular to the pivot axis. A circuit in the circuit housing is responsive to the actuating angle from the float assembly to provide an output signal indicative of the fluid level in the tank.

Abstract: A monitor, shutoff control, and alarm for use with an inlet water supply obtained from a municipal water supply to prevent excessive usage of water due to leakage or human error, that includes a measuring means and shutoff valve connected to the inlet supply, a processor that includes a program for setting threshold values of water volume per unit time anticipated by the particular household, which, when exceeded, will set off an audio alarm or will activate a telephone dialer to call a predetermined number if no one is at home. The system is programmed in volume increments of time, such as hours, days, or weeks, to accommodate systems that include sprinklers which may require some volume of water over a short period of time. The system can be portable. It is easily installed and mounted in conventional water systems for homes, but can be individually adjusted based on the anticipated water usage of a particular household.

Abstract: A system for detecting the level of a liquid in a vessel, comprises a detector assembly including a thermally conductive substrate supported within the vessel. One or more heaters are mounted on the substrate within the vessel. One or more temperature sensors, each associated with a respective heater, are mounted on the substrate. The sensor(s) may be actuated to generate an electrical signal defining a temperature signal indicative of the detected temperature. A processor is electrically connected to the sensor(s) for receiving the temperature signal(s) after actuation of the associated heater(s). The processor is programmed to calculate a “temperature index” proportional to the temperature signal(s). The temperature index(s) indicates the temperature increase detected by the sensor(s) resulting from actuation of the heater(s). This, in turn, indicates the presence of liquid or vapor adjacent to the sensor(s).

Abstract: An electronic controller for controlling the fill, settle and draw operations of three settling tanks which are used with a reverse osmosis unit. The three settling tanks provide a pair of liquid level input signals which indicate the water level within each of the three settling tanks. A bounce eliminator circuit eliminates oscillations from the input signals, providing at its outputs steady state liquid level signals which are active low. The liquid level signals are supplied to a programmable logic device which has a state machine. The state machine sequentially controls the fill, draw and settle operations of the three settling tanks. The programmable logic device provides logic signals which are active low and which activate fill and draw valves associated with each of the three tanks.

Abstract: From the time of power on, an output of a variable frequency generating circuit is kept matching with the resonance frequency of a resonance circuit. When an object of detection comes into contact or to the vicinity of a detection electrode and the resonance frequency of resonance circuit changes, a phase deviation is generated from the output of the variable frequency generating circuit. The deviation is detected by a phase comparing circuit, and a control circuit changes a control voltage so that the oscillation frequency of variable frequency generating circuit is changed to attain phase matching. This change is detected by a detection circuit, and presence/absence of the object is detected.

Abstract: A alarm system for waste liquid discharge blockage for early warning when blockage results from waste liquid. In the blockage alarm system for waste liquid discharge according to the present invention, the discharge line connected to the outlet of waste liquid of the machine is arranged such that the discharge line is angled in the ranges of about 185 to 265 degrees to allow the waste liquid flow smoothly. The first pipe and the second pipe of the sensing line are arranged roughly under the connection of the discharge line and the lowest outlet, and located to make the angle between the first pipe and the discharge line of the sensing region in the range of about 95 to 175 degrees and the angle between the second pipe and the discharge line of the sensing region in the range of about 95 to 175 degrees when the discharge line of the sensing region is vertical. The flow back of the waste liquid into the sensing region can be inhibited. A sensor can be provided in the sensing line for detection of blockage.

Abstract: A fault protective device (48) for limiting the maximum current and voltage applicable to electronic components and wiring (26, 30) located in the fuel tank (10) of an aircraft. Particularly, a fuel gauging system circuit (18) extends from a generator (20) located outside the tank to at least one probe (14) located in the tank and from the probe to instrumentation (24) outside the tank. The device is electrically coupled to the circuit at the tank wall (28) and includes a voltage clamp (50) and series inductor-capacitor resonant circuit (46), so that the resonant circuit provides a low series impedance when applied with a signal at the operating frequency of the input signal applied by the generator but provides a high series impedance when experiencing a signal of a different frequency indicative of a system fault.

Abstract: A flow detector includes solid state delay circuitry coupled to a flow indicating device. In response to flow being indicated, the delay circuitry is enabled. After a preset delay interval, if flow is still being indicated, an output signal can be generated. The flow indicating device can be a two-state mechanical switch. A mode setting element can be used to configure the detector for different types of installations.

Abstract: A time delayed fluid level monitoring device (10) for monitoring the level of oil in a compressor sump (not shown) comprises a housing (12) which defines an internal cavity (18). Two orifices (20 and 22) are provided at end (16) of housing (12) to allow fluid communication between the interior of the compressor sump and the cavity (18). Orifice (20) is a restriction hole for restricting the flow of fluid between cavity (18) and the compressor sump so that there is a time delay between the equalization of fluid levels within the compressor sump and cavity (18). Orifice (22) is of a vent hole. A float (24) is pivotally supported within the cavity (18) as provided at one end (28) with a magnet (36) for switching a reed switch (26) extending through the housing (12).

Abstract: A fuel supply indicator arrangement for a motor vehicle fuel tank includes a device for generating a fuel consumption signal to measure the fuel consumption of an internal combustion engine. A fuel supply indication is provided by an end position switch arrangement in the fuel tank including several end position switches located above a fuel withdrawal point at heights corresponding to predetermined fill levels, the end position switch arrangement being of such configuration that it emits an end position switch signal depending on which of the end position switches is immersed in fuel, and an electric circuit calculates a value for the fuel supply indication from the fuel consumption signal and the end position switch signals.