Positive search report for the magnetorheological damper patent application

The patent application filed by Inventra’s founding team for a magnetorheological semi-active damper system received a positive search report on 30 March 2016.

The application had entered the records of the Turkish Patent Institute under application number 2013/12816. The institute was renamed the Turkish Patent and Trademark Office (TÜRKPATENT) by Industrial Property Law No. 6769, published in the Official Gazette on 10 January 2017.

How the magnetorheological fluid works

In the damper system covered by the application, a magnetorheological smart fluid takes the place of the oil and oil derivatives used in passive dampers. The fluid combines pure iron particles 3 to 10 micrometers in diameter with a carrier liquid (mineral or synthetic oil, water or glycol). Additives keep the iron particles from settling and prevent metal wear.

With no external influence on the fluid, the iron particles sit in random positions and the fluid behaves as a Newtonian liquid. Under a magnetic field the particles line up along the field and form chain structures. These chains act as a sieve and impede the passage of the fluid through the region, and the internal resistance to flow makes the liquid behave as a fluid of much higher viscosity.

Under a magnetic field the smart fluid moves between free flow and a semi-solid state, bidirectionally and instantaneously, at a controlled yield stress. In proportion to the strength of the applied field, the yield stress can reach 100 kPa within milliseconds. The magnetic polarization mechanism is unaffected by temperature, so the system can be used across a very wide temperature range.

What the design set out to do

The application sets out four design aims: to shrink the damper while holding its damping effect, to make the damping force linear and continuously controllable, to shorten the piston while lengthening its travel, and to produce different damping forces in compression and in extension.

Where the project leads today

The damper is not a catalog product. The record is kept in the news archive because designing the mechanism, the drive electronics and the control loop as one piece of work started with this project. The same path is followed today in gimbal, positioner and mast design, as described on the Electromechanical System Design page.

The same project won two awards in 2013 at New Ideas New Business (Yeni Fikirler Yeni İşler), run jointly by METU and METU Technopolis, as reported in Two awards at the New Ideas New Business competition.

About Inventra

Inventra Mühendislik A.Ş., founded in 2015, designs, manufactures, integrates and qualifies reconnaissance and surveillance systems at its R&D Center and its Integration and Test Center in Ankara. Its product line covers multi-channel stabilized thermal imaging gimbals, single and dual axis positioners, masts, tripods and portable climatic rack cabins.

Media contact: infoinventras3.com