1872results about "Level indicators by physical variable measurement" patented technology

Systems and methods for the identification, powering and control of products and product packaging. The systems can include a point of sale display having a contactless power supply. The contactless power supply can provide a source of wireless power for products and product packaging. The products and product packaging can include light emitting diodes, e-ink displays and printed speaker circuits that activate as the operating frequency of the contactless power supply varies. Other embodiments include product level sensors, inductive reader networks, printed temperature sensors, product alignment systems, passive identification circuits and methods for controlling operation of the same.

RFID tags attached to a product contain information regarding the product and communicate this information to a reader. This information can include the age of the product, the amount of product left and preparation or care instructions for the product. To record the age of a product, a timer is initiated in the RFID tag. Thereafter, the elapsed time on the timer can be read and displayed by the reader. For other products, the RFID tag can have contacts monitoring the level of remaining product. Once the contacts sense that the amount of product is low, this information can be transmitted and communicated by the reader. Preparation and care instructions are prerecorded on the tag. Instructions can also be communicated between a product and a base, such as a heater.

A level sensor for detecting the level of a medium contained in a vessel comprises:

• • an array of capacitive elements designed to be associated with the vessel (1), comprising a plurality of electrodes (J₁-J_n), spaced apart from each other along an axis of detection (X),
  • an insulation layer (16) for electrically insulating the electrodes (Ji-L) with respect to the inside of the vessel (1),
  • a controller (24) having a plurality of inputs.

Each capacitive element comprises at least one of a single electrode and a group of electrodes connected in common to each other, the single electrode or the group of electrodes being connected to a respective input of the plurality of inputs.

The controller (24) is prearranged for discriminating a value of electrical capacitance associated with each electrode (J₁-J_n) to deduce the level of the medium present in the vessel.

A chemical vessel used for holding a liquid chemical precursor is disclosed comprising a liquid level sensor tube. The liquid level sensor tube is configured to operate in an environment where the liquid chemical precursor is heated to a point of boiling or vaporization. The liquid level sensor tube comprises housing with a slot built in to prevent any false readings of sensors disposed within the liquid level sensor tube.

A capacitive liquid level indicator having a capacitive sensor array superposed on each side of a dielectric substrate, wherein the sensor signal detection electronics are located immediately adjacent each capacitive sensor. These provisions result in high sensitivity of detection of submergence in the liquid, as well as essentially eliminating parasitic electric fields. The preferred capacitive sensors are interdigitated capacitors, and the preferred sensor signal detection circuit is an RC bridge and a comparator, wherein the comparator senses a voltage difference in the RC bridge between a sensor resistor and sensor capacitor of a first leg thereof and a reference resistor and reference capacitor of a second leg thereof. It is preferred for the capacitive liquid level indicator to be coated with a low dielectric conformal coating to thereby insulate the electronic components (inclusive of the capacitive sensors) thereof with respect to the liquid into which it is submerged. The sensitivity of the capacitive liquid level sensor according to the present invention is extremely high; as a result, a reference capacitive sensor is obviated, and there are no false indications of liquid due to any film of the liquid clinging to an exposed portion of the capacitive liquid level sensor.

Provided is a sensor operative to track changes in a liquid level of a hand-held liquid container, the sensor comprising: an ultrasonic liquid-level sensor configured to indicate a liquid level of a liquid in a hand-held liquid container, wherein the ultrasonic liquid-level sensor is capable of indicating the liquid level when the surface of the liquid is less than 20 centimeters away from the ultrasonic liquid-level sensor; a radio transmitter; and a processor configured to draw power from a portable power source, receive liquid-level indications from the ultrasonic liquid-level sensor, and cause the radio transmitter to transmit data indicative of changes in the liquid level.

A method for determining a filling level of a product contained in a tank, by means of a radar level gauge system comprising a transceiver for generating, transmitting and receiving electromagnetic signals; a probe connected to the transceiver and arranged to guide a transmitted electromagnetic signal from the transceiver towards and into the product inside the tank, and to return a reflected electromagnetic signal resulting from reflection of the transmitted electromagnetic signal by a surface of the product back towards the transceiver; and a plurality of reference reflectors each being arranged at a respective known position along the probe and being configured to reflect a portion of the transmitted electromagnetic signal back towards the transceiver. The method comprises the steps of identifying, based on received electromagnetic signals reflected by the reference reflectors, a set of reference reflectors located above the surface of the product; selecting first and second reference reflectors comprised in the set of reference reflectors; determining a propagation velocity compensation factor based on a known distance between the first and second reference reflectors and a distance therebetween determined using received electromagnetic signals reflected by the first and second reference reflector, respectively; and determining the filling level based on a received electromagnetic signal reflected by the surface of the product, and the propagation velocity compensation factor.

A system for detecting a container or contents of the container. The system includes a diffuser for retaining the container, where the container is configured to hold an active material therein and may include a wick extending therefrom. The system further includes a sensor positioned to detect, for example, the container retained in the diffuser and/or the contents of the container retained in the diffuser.

Noninvasive method for determining the liquid level and density inside of a container having arbitrary dimension and shape. By generating a flexural acoustic wave in the container shell and measuring the phase difference of the detected flexural wave from that of the originally generated wave a small distance from the generated wave, while moving the generation and detection means through the liquid/vapor interface, this interface can be detected. Both the wave generation and wave detection may be achieved by transducers on the surface of the container. A change in the phase difference over the outer surface of the vessel signifies that a liquid/vapor interface has been crossed, while the magnitude of the phase difference can be related to fluid density immediately opposite the measurement position on the surface of the vessel.

A microwave level gauge for measuring a level of a process material in a tank includes a ceramic seal and a microwave conductor. The ceramic seal is disposed adjacent to an opening in the tank and adapted to isolate circuitry from the process material. The microwave conductor is electrically coupled to the circuitry and extends through the hermetic seal and into the process material in the tank. The ceramic seal and an isolating adapter cooperate to isolate the microwave conductor from the process fluid and from external forces.

The invention discloses a water level monitoring system based on image processing and a method, which mainly solve the problem that water level cannot be monitored automatically in the prior art. The water level monitoring system comprises a water level gauge, a water level image processing module, a wireless communication module and a central management server module. Working principle of the system is that: firstly the water level gauge is used for marking the water level, water level images marked by the water level gauge can be collected by a camera, the water level image processing module further performs automatic positioning, skew correcting and recognizing on the water level gauge in the water level images to obtain water level data and transmits the water level data to the wireless communication module through a wireless communication network, then the wireless communication module transmits the received water level data to the central management server module which stores the received water level data into a computer data base so as to draw current hydrograph in real time, when the current water level is higher than a preset water level, alarm information can be given out, and accordingly automatic monitoring of the water level can be achieved.

An improved apparatus and a method of measuring and interpreting reliably, simply and accurately the information on continuous liquid level, liquid temperature and other liquid properties within a vessel. The apparatus could be made of a powered heater element and temperature sensors can be screen-printed, vacuum deposited, etched, welded, soldered or plated on one or both sides of a single rigid or a flexible substrate. The geometry of the heater determines the curve shape, such as steepness or shallowness of a temperature profile along a heater. Various parallel and serial configurations of thermocouples or temperature sensors can be used to measure the temperature along a heater. Simultaneous measurements from all the temperature sensors, before and after heat is applied, are used to generate accurate temperature profiles for the entire heater. Different features of the temperature profiles will determine accurately the liquid level, liquid temperature and other liquid properties. Apparatus of the invention may also be used to detect ice formation.

Apparatus and methods for employing electrical properties of water to indicate the level of filtered water in a filtered water container. The container is fitted with a hopper that holds unfiltered water. The hopper is fitted at its base with a removable and replaceable filter cartridge. Water is filtered by draining through the filter medium contained in the filter cartridge into the lower portion of the container. The water level in the lower portion of the container is monitored by means of one or more water level detector strips in the lower portion of the container. The detector strips are in electrical communication with a detection circuit and a control unit. The control unit uses the detection strips to monitor water level and uses such data to track filtered water consumption and to determine when the filter cartridge should be replaced.

A multi-function sensor is disclosed for measuring the conditions within a container, such as fluid level, turbidity, temperature and pressure. The sensor incorporates a fluid level sensor module, a turbidity sensor module, a temperature sensor module and a pressure sensor module. The fluid level sensor module utilizes a plurality of thermocouple junctions grouped in pairs with the pairs being spaced along a line extending generally in the direction in which the liquid level may vary. The thermocouple junctions are connected in series and produce a signal indicative of the level along the sensor. Turbidity, temperature, and pressure sensor modules may also be incorporated in the multi-function sensor. Alternatively, a fluid flow rate sensor module may be included in place of the liquid level sensor module.

Systems and methods for the identification, powering and control of products and product packaging. The systems can include a point of sale display having a contactless power supply. The contactless power supply can provide a source of wireless power for products and product packaging. The products and product packaging can include light emitting diodes, e-ink displays and printed speaker circuits that activate as the operating frequency of the contactless power supply varies. Other embodiments include product level sensors, inductive reader networks, printed temperature sensors, product alignment systems, passive identification circuits and methods for controlling operation of the same.

A capacitive fluid level sensor is disclosed that operates without the use of a float, wherein sensing electrodes are spaced to form a measured capacitance that changes in accordance with a changing fluid level, the electrodes forming a sensing element, and being electrically insulated from the measured fluid. The sensing element is fabricated such that it can be attached to the outside of a dielectric wall of a vessel, or embedded within a dielectric material. An interdigital comb configuration of sensing element is also disclosed in which depressions or gaps are formed into a dielectric material that is present between the fingers of the comb.

A device and method for sensing fluid characteristics, including, temperature, pH and chemistry, comprises a switch affixed to or embedded in a container of a size, shape and density such that said container floats stable in said liquid sensors which measure and report other characteristics of the liquid, such as temperature, pH, viscosity, chemistry or biochemistry.

A temperature sensor is provided for measuring a temperature of a liquid contained in a cooking vessel. The temperature sensor includes a first housing containing processing and wireless communication circuitry, a second housing containing a temperature probe, and a connecting member carrying wiring that connects the processing and wireless communication circuitry to the temperature probe. The temperature sensor also includes a fastener coupled to the first housing and configured to removably affix the temperature sensor to a sidewall of a cooking vessel such that the first housing is exterior to the cooking vessel, and the second housing extends over an interior bottom surface of the cooking vessel. The temperature probe is extendible from or retractable into the second housing to an adjustable height above the interior bottom surface of the cooking vessel and configured to measure a temperature of a liquid contained in the cooking vessel.

A non-intrusive refrigerant charge level indicator includes a structure for measuring at least one temperature at an outside surface of a two-phase refrigerant line section. The measured temperature can be used to determine the refrigerant charge status of an HVAC system, and can be converted to a pressure of the refrigerant in the line section and compared to a recommended pressure range to determine whether the system is under-charged, properly charged or over-charged. A non-intrusive method for assessing the refrigerant charge level in a system containing a refrigerant fluid includes the step of measuring a temperature at least one outside surface of a two-phase region of a refrigerant containing refrigerant line, wherein the temperature measured can be converted to a refrigerant pressure within the line section.

A sensor device (10) and a method for measuring a viscosity of a sample of a liquid. The sensor features a chamber (12) for receiving the sample of the liquid, two electrodes (18) disposed either on the surfaces of the chamber, but possibly isolated from contacting the sample, or electrodes located externally to the chamber, and a capacitance measuring circuit (25). The sensor is used by connecting to a measurer for determining a capacitance on the electrodes, such that the capacitance directly reflects a volume occupied by the sample of the liquid. Preferably, the liquid is blood and the capacitance is used to determine the clotting time of the blood. Also preferably, a cover for the chamber is provided with at least one aperture, which more preferably is a mesh. Alternatively, an electrical property such as the amplitude of current passed through the sample is used to determine clotting time. Also preferably, the time period required for the maximum capacitance to be reached could be measured. Alternatively, the capacitance could be measured after a fixed time period (34) had elapsed. Also alternatively, the time period required for the maximum current to be reached could be measured, or the amount of current could be measured after a fixed time period had elapsed. In preferred embodiments of the present invention, a kit for measuring the clotting time of blood is provided. In other preferred embodiments of the present invention, methods are provided for using the kit and device of the present invention.

A humidifier includes a tub configured to contain a supply of water and a heater including a first polymer film having an electrically conductive circuit provided upon a surface. The first polymer film is electrically insulating and the tub is formed of molded resin and the heater is molded at least partially within the resin. A respiratory apparatus for delivering a flow of breathable gas to a patient includes the humidifier. A method of humidifying a flow of pressurized breathable gas includes passing the flow of pressurized breathable gas over a supply of water contained in a tub. The tub is formed of molded resin and a heater including a first polymer film having an electrically conductive circuit on a first surface is molded at least partially within the resin.

A capacitive sensor assembly for detecting relative movement or position between objects, such as liquid level in a tank or reservoir, movement of one machine component with respect to another, and so on, includes one or more antenna probes connected to an integrated chip normally associated with touch-screen displays. Each antenna probe operates independently and may be formed as insulated conductive wires or conductive traces between layers of a stiff or flexible substrate, such as a PCB, with the substrate material serving as the insulating layers. Each antenna probe has a different length representing different measurement positions or locations between the objects being measured to provide dynamic calibration of the measurement under changing environmental conditions.

A guide pipe is formed from a metal material, and its internal cross section has a circular shape whose diametric dimension gradually becomes smaller with a distance from an ultrasonic sensor. That is, the guide pipe is formed so that a route for transmitting an ultrasonic wave generated from the ultrasonic sensor may be tapered from this ultrasonic sensor toward a reflector plate. Thus, the acoustic pressure level of the ultrasonic wave which enters the reflector plate can be made higher than a value in a prior-art liquid level detecting apparatus. Accordingly, the energy of the ultrasonic wave generated from the ultrasonic sensor can be utilized for liquid level detection at a high efficiency, so that a fuel liquid level detecting apparatus capable of accurate liquid level detection can be provided.

A device for determining a location of an interface between a first fluid and second fluid includes a non-mechanical sensor that measures a selected parameter of interest relating to the fluid surrounding the sensor (“the surrounding fluid”) and a processor for processing the sensor measurements. The non-mechanical sensor measures a parameter relating to the surround fluid without physically co-acting with the surrounding fluid. Exemplary parameters such as thermal properties, electrical properties, fluid properties, and magnetic properties can be measured. The processor is programmed to process the sensor measurements to identify one or more characteristics in the measurements that can indicate the nature of the fluid being measured and thereby determine the location of the interface. The determined location can be used to operate a downhole device such as a pump, to provide real-time monitoring of well conditions, to record data for long-term reservoir characterization, or to actuate an alarm.

A method for ascertaining and/or evaluating the fill-state of a container filled with at least one medium, wherein high-frequency, electromagnetic, measuring signals are emitted by a fill-level measuring device and received back as wanted echos reflected at an interface of the media. The electromagnetic, measuring signals are received back as an end echo reflected at a measuring range end, wherein, from the received wanted echos and the end echo, an echo curve is formed as a function of travel-time and/or the travel-distance, wherein, by means of a search algorithm integrated in the fill-level measuring device, number, existence and/or position of individual wanted echos and of the end echo in the echo curve are/is ascertained and applied for classifying the currently present fill-state in the container relative to predetermined, stored, fill situations in the container. On the basis of the classified fill situation in the container, with a distance value of the fill-level and/or a distance value of the separating-layer are/is associated belonging travel-times and/or belonging travel-distances of the individual wanted echos and/or end echo in the echo curve.

A water level controller for a tank has control circuitry and multiple conductance terminals connected to the control circuitry and located at different heights from the other. By such an arrangement, the water level can be determined when the conductance of the water measured by corresponding conductance terminals becomes zero. The water inlet can be controlled to add to the tank by the control circuitry as the conductance measured by two of the corresponding terminals becomes practically negligible. Consequently, the water level in the tank can be accurately controlled, and the controller can be used with pure water so as to enlarge the useful scope of the controller.

A sensor device includes a communication transmitter configured to transmit a sensor device identifier. The sensor device includes a communication receiver configured to receive a sensor configuration associated with the sensor device identifier. The sensor device includes an interrogation signal transmitter configured to transmit an interrogation signal based at least in part on the received sensor configuration to determine an identifier associated with an amount of content included in a container engaged by the sensor device.

A capacitive position sensor has a periodic array of electrodes which form capacitors between pairs of the electrodes. The location of a dielectric inhomogeneity in the vicinity of the sensor is determined by comparison of the relative change in the capacitance of the capacitors. The comparison may be carried out using a capacitive Wheatstone Bridge arrangement. The sensor configuration has the advantage that it is independent of the absolute value of the dielectric constant of the environment in which the sensor is located.

A wireless (e.g., radio) system and method for automatic water level maintenance of, e.g., a swimming pool utilizing capacitive liquid level sensing. A reference electrode allows water level sensing independent of the water chemistry or temperature. Capacitive electrodes having areas larger than the reference electrode sense various liquid levels when the liquid covers an area of any sensing electrode equal to the area of the reference electrode. Averaging is incorporated to filter out effects of wind or other disturbances. Upon sensing a given condition, the transmitter transmits a sensed condition to a remote receiver for control of valves and pumps for changing the water level in the pool. The receiver includes safety timers for filling and emptying to protect against equipment failure or communications faults. User selectable identification allows identical such radio systems to operate within proximity to each other. Power saving features are used to extend battery life.

A low ink sensing system is combined with an ink cartridge detection system to enable a more efficient ink jet printer. An ink container which supplies ink to an associated printhead is modified by the incorporation of two light directing elements, in the preferred embodiment, a faceted prism and a roof mirror, into a transparent wall of the container housing. The cartridge, comprising the ink container and associated printhead, is mounted on a scan carriage. Periodically, the carriage is conveyed to a sensing station comprising a pair of light sources and a commonly used photosensor. A first light source is energized and a beam of light is directed to a location where the roof mirror, would be positioned if the cartridge is present. If the cartridge is absent, lack of a reflected return signal is sensed, indicating a cartridge has not been inserted. Print operation is halted until a cartridge is inserted. If a cartridge is properly inserted, the roof mirror returns most of the incident light to the photosensor which generates a signal indicating the presence of the cartridge. A second light source is then energized and directed towards the faceted prism, which is either immersed in ink or exposed to air within the interior of the container. If the latter, light is internally reflected by the prism facets back to the photosensor. If a print operation has been in progress, and the ink level has fallen, the common photosensor detects either a strong or weak redirected light component and initiates a status check and generates appropriate displays of low ink level or out of ink warnings.