Caterpillar's US 6,688,280 to be re-examined(?); derivation issue?

James Weber and Scott Leman are named inventors on two patents (each entitled Air and fuel supply system for combustion engine): US 6,651,618 (app. 370,852 filed February 20, 2003 and issued November 25, 2003) and US 6,688,280 (app. 143,908 filed May 14, 2002 and issued Feb. 10, 2004). The '618 and '280 patents explicitly cite US 6,279,550 to Clyde Bryant.

Weber and Leman are the only named inventors on the '280. There are other named inventors on the '618, including the first named inventor Gerald Coleman.

Although the '618 issued BEFORE the '280, the '618 is a continuation-in-part of application Ser. No. 10/143,908 filed on May 14, 2002. Thus, the '280 is the PARENT.

The first claim of the '618 recites:


1. A method of operating an internal combustion engine including at least one cylinder and a piston slidable in the cylinder, the method comprising:

supplying a mixture of pressurized air and recirculated exhaust gas from an intake manifold to an air intake port of a combustion chamber in the cylinder;

selectively operating an air intake valve to open the air intake port to allow the pressurized air and exhaust gas mixture to flow between the combustion chamber and the intake manifold substantially during a majority portion of a compression stroke of the piston; and

operably controlling a fuel supply system to inject fuel into the combustion chamber after the intake valve is closed.



The first claim of the '280 recites:

A method of operating an internal combustion engine including at least one cylinder and a piston slidable in the cylinder, the method comprising:

supplying pressurized air from an intake manifold to an air intake port of a combustion chamber in the cylinder;

selectively operating an air intake valve to open the air intake port to allow pressurized air to flow between the combustion chamber and the intake manifold substantially during a majority portion of a compression stroke of the piston; and

operably controlling a fuel supply system to inject fuel into the combustion chamber after the intake valve is closed.

--> Discussion from an Atlanta newspaper (below) suggests that the first filed patent, US 6,688,280, is the subject of a re-examination. Although NOT mentioned in the newspaper article, note that the '280 patent cites to the Bryant patent, US 6,279,550 (filed May 23, 1997 issued August 28, 2001). The '550 describes the following priority: This application claims the priority of U.S. Provisional Application 60/022,102, filed Jul. 17, 1996; 60/023,460, filed Aug. 6, 1996; 60/029,260, filed Oct. 25, 1996; and 60/040,630, filed Mar. 7, 1997. Furthermore, this application is a continuation-in-part of U.S. application Ser. No. 08/841,488, filed Apr. 23, 1997, abandoned. [Perhaps the re-examination request will be denied.]

The first claim of the '550 patent recites:

An internal combustion engine, comprising:

an engine block defining at least one cylinder therein, two cylinder inlet ports communicating between said cylinder and a source of air, and an exhaust port through which exhausted gases are expelled from said cylinder;

a piston movably mounted within said cylinder;

an intake valve selectively occluding each inlet port;

an exhaust valve selectively occluding said exhaust port;

at least one compressor in fluid communication via a conduit between said source of air and at least one cylinder inlet port;

at least one air cooler interconnected between said compressor and said inlet port; and

means for directing low pressure air to one of said inlet ports during an intake stroke of the piston and for directing air highly compressed by said compressor to the other of said inlet ports during a compression stroke of said piston, wherein one of said intake valves occupies an open position only while the other of said intake valves occupies a closed position.

****from the Atlanta Journal-Constitution:

-->A 77-year-old retired chemist from Alpharetta has challenged a patent for a prize-winning Caterpillar Inc. engine, claiming it was based on his invention.

Clyde Bryant has filed a formal request that the U.S. Patent and Trademark Office re-examine a 2004 patent for technologies that are central to the performance of the Caterpillar engine.


Clyde Bryant has filed a formal request with the U.S. Patent and Trademark Office.

The goal of such requests is to have the patents revoked.

Caterpillar says it spent hundreds of millions of dollars developing the new engine around a fuel control system it calls ACERT, which stands for Advanced Combustion Emissions Reduction Technology.

The system increases power while cutting air pollution, the Illinois-based supplier of heavy industrial equipment says.

Three months ago, two Caterpillar engineers, Jim Weber and Scott Leman, shared a national Inventor of the Year award for the patent being challenged by Bryant.

Both Bryant's patent, issued Aug. 28, 2001, and the patent issued last February to Weber and Leman and assigned to Caterpillar describe ways to control the introduction of fuel and a charge of cooled, compressed air into the cylinder of an engine.

Precisely timed, the cooled air introduction increases combustion efficiency and causes engine exhaust to contain less air pollution, both patents claim.

Language cited

Bryant's request for a re-examination repeatedly cites similar phrases in his patent and the later Weber-Leman patent.

For example, Bryant says that in his engine, a "variable valve timing system can control the times of opening and closing intake valves." The Caterpillar patent offers "a variable intake valve closing mechanism to keep the intake valve open."

Bryant says his engine would run "so that the initial injection of fuel would be a pilot injection." The Caterpillar patent describes a "pilot injection of fuel at a predetermined crank angle before a main injection."

Bryant refers to a valve remaining open "for at least 90 degrees crank angle past bottom dead center," and Caterpillar says the same process would occur when conditions were "at least 90 degrees crank angle after bottom dead center."

Altogether, Bryant's challenge lists 40 separate innovations that he says appear in his 2001 patent, then reappear in the 2004 invention by Leman and Weber.

Records of the U.S. Patent and Trademark Office indicate Leman and Weber filed for their patent on May 14, 2002.

In a prepared statement from its general patent counsel, William B. Heming, Caterpillar said:

"Caterpillar's ACERT Technology is a great advancement in engine technology and has received many accolades from industry. Given this media attention, it is not unexpected to receive challenges such as this, and Caterpillar will defend against these challenges vigorously."

A spokeswoman for the company declined to say anything beyond that.

Licenses offered

Bryant, the founder and chairman of Entec Engine Corp. of Alpharetta, referred questions to a lawyer, Louis T. Isaf of Atlanta.

Isaf would not respond to questions about whether the Bryant patent had been shown to Caterpillar officials prior to the approval of the Leman-Weber patent. [Note: clearly the '550 patent of Bryant was known by Caterpillar prior to the February 2004 issuance because it is cited within the '280 patent.]

"Entec has contacted many of the major engine manufacturers, seeking assistance with the manufacture of Entec engines and also offering licenses," Isaf said in a prepared statement.

He would not say which engine manufacturers the company had contacted or specifically whether they included Caterpillar.<--