3993results 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 fluid volumetric pumping system has a fluid pump and capacitor plates disposed around a pump chamber of the fluid pump. The capacitance between the capacitor plates changes as the volume of fluid in the pump chamber changes. An electrical circuit measures a change in the capacitance between the plates and outputs a signal indicative of the volume of fluid in the pump chamber. The pump having the capacitance sensor of the present invention fluidly connects to a patient. In an embodiment, a peritoneal dialysis system provides dialysate to the patient via the pump, and the capacitance sensor measures the volume of dialysate supplied to and drained from a peritoneal cavity of the patient.

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.