PACCAR has patented a method to evaluate Diesel Exhaust Fluid (DEF) quality in emissions aftertreatment systems. By analyzing NOx conversion efficiency in SCR units, the system adjusts DEF dosing to optimize performance. This innovation ensures efficient operation of engines while reducing harmful emissions. GlobalData’s report on PACCAR gives a 360-degree view of the company including its patenting strategy. Buy the report here.

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According to GlobalData’s company profile on PACCAR, Driving behavior monitoring was a key innovation area identified from patents. PACCAR's grant share as of February 2024 was 75%. Grant share is based on the ratio of number of grants to total number of patents.

Method for evaluating quality of def in emissions system

Source: United States Patent and Trademark Office (USPTO). Credit: PACCAR Inc

A recently granted patent (Publication Number: US11927126B2) discloses a method for evaluating the quality of diesel exhaust fluid (DEF) in an emissions aftertreatment system (EAS) comprising an upstream selective catalytic reduction (SCR) unit and a downstream SCR unit. The method involves varying the ammonia to NOx ratio of the internal combustion engine exhaust gas entering the upstream SCR unit during steady-state operation, determining the NOx conversion efficiency of the upstream SCR unit at different ratios, comparing it to a target efficiency, and using the result to evaluate the DEF quality. This evaluation directly impacts the dosing of DEF to the EAS, ultimately reducing the NOx content of the exhaust gas in the downstream SCR unit.

Furthermore, the patent includes additional claims such as initiating the evaluation of DEF quality after a significant change in the DEF tank level, adjusting the dosing of DEF to the upstream SCR unit based on the evaluation result, and generating a diagnostic signal based on the evaluation outcome. The method also involves reducing the NOx content of the exhaust gas by 95% or more in the downstream SCR unit, emphasizing the efficiency of the aftertreatment system. The target NOx conversion efficiency for the upstream SCR unit is determined from a lookup table, which accounts for the age of the unit, ensuring accurate evaluation and adjustment of DEF dosing. Overall, this patented method offers a comprehensive approach to maintaining optimal DEF quality and emission control in EAS operations.

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GlobalData Patent Analytics tracks bibliographic data, legal events data, point in time patent ownerships, and backward and forward citations from global patenting offices. Textual analysis and official patent classifications are used to group patents into key thematic areas and link them to specific companies across the world’s largest industries.