The Grizzly® and RuMble Grate® are patented and trademarked products and have a patented methodology. Before the invention of the of the Grizzly® and the RuMble Grate® (or the subsequent various knock-off copies of the product existed), only gravel pads were used to control track out. In late 2002, the Grizzly® and the RuMble Grate® were created. RuMble Grates® were introduced in Arizona, Nevada and California in 2003 on construction sites. Since then it has spread across the country as the simplest and most economic way to minimize track out for construction sites, landfills, power plants, batch plants and manufacturing applications. After introduction Very quickly various “patent infringing knock-offs” were being built to copy the rumbling effect of the Grizzly® and the RuMble Grate®. The methodology in the form of rumble strips, steel plates and products under various names, The knock-offs without our proprietary dimensions, had very limited actual performance, as compared to the Grizzly® and the RuMble Grate®. The Grizzly® brand RuMble Grate® has collection space underneath which collects the dust, dirt and rock in dead-fall space when falling off the vehicle. It uses no water or electricity but provides 85% effective removal and collects the solid materials in the dead-fall space below the RuMble Grate®.
Patents numbers 6,981,818 and 6,881,006 and 7,059,799 were product patents focusing on the product itself. Patent 7,775,739 was the methodology that the products introduced.
If you are a company attempting to copy this technology, you should be aware the method and product (regardless of the physical characteristics of your knock-off device) is Federally protected under patent law and the brand and product name is Trademarked.