Toyota has been the target of a number of patent infringement suits involving hybrid electric vehicles in the last several years (e.g., see previous posts here, here and here).
So instead of waiting to be sued again, this time the automaker got a jump on Palo Alto-based hybrid and electric vehicle technology company Efficient Drivetrains Inc. (EDI) and brought its own action for declaratory judgment of noninfringement and invalidity of several patents relating to power output control and charge depletion methods for hybrid electric vehicles.
The complaint (Toyota-EDI_Complaint), filed in federal court in San Jose, California, lists U.S. Patents Nos. 5,842,534 (’534 Patent), 6,054,844, 6,116,363, 6,809,429 (’429 Patent) and 6,847,189 (’189 Patent) (collectively “Asserted Patents”) and also names the Regents of the University of California, the owner the Asserted Patents, as a defendant.
According to EDI’s web site, the company holds an exclusive license for the entire University of California – Davis patent portfolio relating to hybrid electric vehicles and continuously variable transmissions (read more about the licensed technology here). UC Davis Professor Andy Frank is the named inventor on all of the Asserted Patents.
Most of the Asserted Patents are directly related, or at least incorporate and improve upon each other, and four out of five trace priority back to an original filing date of 1995.
The earliest patent, the ’534 Patent, was filed in 1997 and is directed to methods and apparatus for controlling a hybrid electric vehicle to optimize efficiency in varying driving conditions.
The method is performed by sensing the vehicle speed and battery depth of discharge (steps 110 and 120) during operation by the electric motor (12) and comparing them with a control curve (150).
If those parameters exceed a predetermined threshold, the internal combustion engine (14) is brought on line by engaging the clutch (step 170) and turning on the internal combustion engine (14) (step 180).
The electric motor (12) can be used to supply additional power (200) if the need for additional power demand is sensed (190). If the internal combustion engine (14) is operating at closed throttle and the brake pedal is depressed for deceleration (210), the electric motor (12) is operated in regeneration mode (230).
Through continuation applications, the subsequent patents claim improvements upon and variations of the methods of the ’534 Patent such as power output control where the internal combustion engine is coupled to a continuously variable transmission (’429 Patent) and control methods for hybrid electric vehicles with smaller battery packs (’189 Patent).
According to the complaint, EDI’s counsel offered Toyota a license to the Asserted Patents, and subsequently contended that Toyota’s hybrid electric vehicles infringe the Asserted Patents and indicated their intention to enforce the patents against Toyota. Apparently, that’s when Toyota took matters into its own hands.
Eric Lane is a patent attorney at Luce, Forward, Hamilton & Scripps in San Diego and the author of Green Patent Blog. Mr. Lane can be reached at elane@luce.com.
