Ward Effect® Technology is protected by a portfolio of granted patents across multiple jurisdictions, with a further full application now under examination at IPONZ. All patents are held by David George Ward, sole inventor.
The foundation patent establishing the Ward Effect® principle. A circuit comprising a microphone, speaker, frequency control device, volume control device, amplifier, frequency reader and spectrum analyser is set up around a container or vessel. Oscillation is created by applying power to the amplifier. The oscillating frequency of the circuit changes measurably as the volume of contents changes — providing a non-intrusive method of measuring content in liquid, solid, semi-solid or granular form. The method is particularly useful where intrusive measurement creates issues with product safety, toxicity or corrosivity, and where access to vessels or pipes is difficult. Applications include pipeline inspection, in-situ remote measurement, and detection of biofilm or algal growth at micron scale.
An improvement on NZ 739314 incorporating a resonant able object (90) as a sensor that establishes sympathetic resonance with the target object. Power applied to the amplifier creates an initial fixed standing wave. Adjusting or changing components invokes a new parasitic behaviour — now called the Ward Effect® — and reading the oscillating frequency determines changes in conditions inside the vessel. This improvement allows smaller amplifiers and speakers to be used, reducing noise levels significantly, and greatly simplifies component selection for a wide range of target objects. Note: the Philippines grant and related analogue-based patents will be superseded by the ESP32-based Ward Effect® Node system currently in development.
A further improvement creating a Point-Level-Sensor from the parasitic oscillation circuit. By appropriate choice of components, the circuit is tailored to trigger an alarm in binary mode — either "it is" or "it isn't." The resonant able object, microphone and speaker combine into a self-contained sensor (91) that detects presence or absence of liquid, decay of structures, flow of material, or anything that has a resonance which changes with conditions. Applications include chlorine dosing, biofilm detection, LPG level sensing, flow detection, corrosion monitoring, cavitation detection, and load cells.
The analogue Ward Effect® systems of NZ 739314, NZ 770993 and NZ 778527 rely on manual adjustment, single-band operation, and limited ability to resolve multiple simultaneous variables. This invention overcomes these limitations through microcontroller-controlled cycling of a digitally adjustable EQ filter, configured by a sparse Library Entry Format (LEF) system with three-tier retrieval. This bidirectional architecture removes embedded-processor constraints, enabling real-time multi-library interrogation and cross-library vector analysis across a wide range of industrial, environmental, and humanitarian applications.
The Korean Intellectual Property Office (KIPO), acting as International Searching Authority for PCT application PCT/NZ2019/050002, examined five prior art documents spanning 1986–2014 and found that the Ward Effect® — in which a parasitic oscillation circuit self-oscillates to produce a frequency of a non-stationary standing wave controlled by changes in the vessel or pipe being measured, differing from the resonant frequency of the pipe or vessel — was not obvious to a person skilled in the art from any of those documents alone or in combination. All 13 claims of PCT/NZ2019/050002 were found novel, inventive, and industrially applicable.
Patent Status Disclaimer: The patent information on this page is provided for general reference only and reflects the status known to Ward Effect Technology at the time of publication. Patent status, including grant, renewal, lapse, and examination outcomes, may change. Current and authoritative status of any patent should be verified directly with the relevant national patent office — including the Intellectual Property Office of New Zealand (IPONZ), the United States Patent and Trademark Office (USPTO), the Intellectual Property Office of the Philippines (IPOPHL), and the Indian Patent Office (IPO).