US Patent 7568893 Electric air pump for secondary air supply system

Patent 7568893 was granted and assigned to Toyota on August, 2009 by the United States Patent and Trademark Office.

Overview Structured Data Issues Contributors Activity

Is a

Patent

Patent attributes

Current Assignee

Toyota

Patent Jurisdiction

United States Patent and Trademark Office

Patent Number

7568893

Date of Patent

August 4, 2009

Patent Application Number

11100375

Date Filed

April 7, 2005

Patent Primary Examiner

‌

Charles G Freay

Patent abstract

When an air pump is operated, a brush temperature increase rate stored in an ECU in relation to a discharge pressure of the air pump and a brush temperature is multiplied by a calculation cycle time, and the resultant value is cumulatively added. When the air pump is stopped, a brush temperature decrease rate stored in the ECU in relation to the brush temperature is multiplied by the calculation cycle time, and the resultant value is cumulatively added. Each of the cumulative values read from a map is added to and subtracted from an initial brush temperature value, respectively so as to estimate the brush temperature.