In PV Furnace Case Green Patent Litigation Moves Upstream

Despatch Industries (Despatch) is a Minnesota company which designs and makes industrial ovens and furnaces, including furnaces for use in solar cell manufacturing.

Despatch owns U.S. Patent No. 7,514,650, entitled “Continuous infrared furnace,” and directed to a furnace for treating material with infrared radiation which has a mechanism to allow easy access to interior components (’650 Patent).

In October of last year, Despatch sued California competitor TP Solar (TP) for patent infringement in federal court in Minnesota, and last month the court transferred the case to Los Angeles (Despatch-Transfer-Order).

According to the complaint (Despatch-TP_Solar-Complaint), TP is selling furnaces that infringe the ’650 Patent, including the Model MD-225 Firing Furnace with Integrated Dryer.

The ’650 Patent describes a furnace (10) having a heat transfer zone (20), a cooling zone (120), and a conveyor (50) to transport the material to be treated. The heat transfer zone (20) has an upper portion (30) and a lower portion (40).

The lower portion (40) is removable, and can be lowered using a jack (60) to allow access to the interior of the heat transfer zone (20) and the components therein. According to the ’650 Patent:

The access to the interior of the furnace 10 provided by moving the lower portion 40 of the furnace from the bottom of the furnace may allow for, among other things, maintenance or replacement of insulation, lamps, the conveyor, and other elements not easily accessible without moving the lower portion.

So green patent litigation is moving up the supply chain to the players that manufacture for the cleantech manufacturers.

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.