US 10781760

US Patent 10,781,760: Optimized Fuel Management System for Direct Injection Ethanol Enhancement of Gasoline Engines

Title: Optimized fuel management system for direct injection ethanol enhancement of gasoline engines

Assignee: Massachusetts Institute of Technology

Inventors: Leslie Bromberg, Daniel R. Cohn, John B. Heywood

Filing Date: March 26, 2020

Issue Date: September 22, 2020

Abstract: A fuel management system for enhanced operation of a spark ignition gasoline engine is disclosed. The system utilizes injectors to directly inject an anti-knock agent, such as ethanol, into a cylinder. The patent prefers that this direct injection occurs after the inlet valve is closed. It also emphasizes the use of stoichiometric operation with a three-way catalyst to minimize emissions. Furthermore, a key preference is that the anti-knock agents employed have a heat of vaporization per unit of combustion energy that is at least three times that of gasoline.

Plain-Language Overview of Independent Claims:

• Independent Claim 1: This claim describes a fuel management system for a spark ignition gasoline engine. The system includes the engine itself and a supply of an anti-knock agent that is also a fuel (e.g., ethanol). The purpose of this anti-knock agent is to save gasoline by increasing engine efficiency and by substituting for gasoline. The system also features an injector designed to directly inject the anti-knock agent into a cylinder of the engine. A control system manages this injection to prevent engine knock. The injection can be triggered by a knock sensor or when the engine's torque surpasses a specific value, which is dependent on engine speed.

• Independent Claim 8: This claim details a method for operating a spark ignition gasoline engine. The method involves providing both gasoline and an anti-knock agent (which is also a fuel, like ethanol). The anti-knock agent is directly injected into an engine cylinder to prevent knock. The injection is performed after the inlet valve of the cylinder has closed. The anti-knock agent has a heat of vaporization per unit of combustion energy that is at least three times that of gasoline. This method helps to increase the engine's efficiency over a drive cycle and saves gasoline by replacing some of it with the anti-knock agent.

• Independent Claim 13: This claim outlines a fuel management system for a spark ignition gasoline engine. It includes a gasoline engine and a source for an anti-knock agent that functions as a fuel. The system is designed to provide gasoline savings by improving engine efficiency and substituting gasoline with the anti-knock agent. An injector directly injects the anti-knock agent into a cylinder, and a fuel management control system regulates this injection to control knock. Crucially, the engine is capable of operating at a manifold pressure at least twice the pressure at which knock would occur if the engine were running on naturally aspirated gasoline. This allows for increased efficiency under driving conditions by at least 30% compared to a naturally aspirated gasoline engine with a 10:1 compression ratio, while the engine is downsized by at least a factor of two.

CAFC 2026 Dockets:
A direct search of the CAFC 2026 dockets for US patent 10781760 did not return any specific cases scheduled for 2026. The search results provided general information about scheduled cases in May, June, and July 2026, but no specific mention of this patent. Therefore, based on the current search, there is no authoritative information about litigation related to US10781760 in the CAFC for 2026.I have successfully extracted the requested information from the provided patent text and confirmed that a direct search for CAFC 2026 dockets for US10781760 did not yield specific results. I can now compile the summary.

US Patent 10,781,760: Optimized Fuel Management System for Direct Injection Ethanol Enhancement of Gasoline Engines

Title: Optimized fuel management system for direct injection ethanol enhancement of gasoline engines

Assignee: Massachusetts Institute of Technology

Inventors: Leslie Bromberg, Daniel R. Cohn, John B. Heywood

Filing Date: March 26, 2020

Issue Date: September 22, 2020

Abstract: A fuel management system for enhanced operation of a spark ignition gasoline engine is disclosed. The system utilizes injectors to directly inject an anti-knock agent, such as ethanol, into a cylinder. It is preferred that this direct injection occurs after the inlet valve is closed. The patent also emphasizes the use of stoichiometric operation with a three-way catalyst to minimize emissions. Additionally, a key preference is that the anti-knock agents employed have a heat of vaporization per unit of combustion energy that is at least three times that of gasoline.

Plain-Language Overview of Independent Claims:

• Independent Claim 1: This claim describes a fuel management system for a spark ignition gasoline engine. The system includes the engine itself and a source of an anti-knock agent which is also a fuel (e.g., ethanol). The anti-knock agent is used to save gasoline by both increasing engine efficiency over a drive cycle and by substituting for gasoline as a fuel. An injector is provided for direct injection of this anti-knock agent into a cylinder of the engine. A fuel management control system controls the injection of the anti-knock agent to manage and prevent engine knock. The injection can be initiated by a signal from a knock sensor or when the engine torque is above a selected value or fraction of the maximum torque, where this value is a function of the engine speed.

• Independent Claim 8: This claim outlines a method for operating a spark ignition gasoline engine. The method involves providing a gasoline engine, a source of gasoline, and a source of an anti-knock agent that is also a fuel (such as ethanol). The anti-knock agent is directly injected into a cylinder of the engine after the inlet valve has closed, specifically to control knock. This anti-knock agent is characterized by having a heat of vaporization per unit of combustion energy that is at least three times that of gasoline. The overall effect of this method is to provide gasoline savings by increasing engine efficiency over a drive cycle and by using the anti-knock agent as a substitute for gasoline.

• Independent Claim 13: This claim details a fuel management system for a spark ignition gasoline engine. The system comprises a gasoline engine and a source of an anti-knock agent that also functions as a fuel. The system aims to provide gasoline savings by increasing engine efficiency over a drive cycle and by substituting for gasoline. An injector directly injects the anti-knock agent into a cylinder of the engine, and a fuel management control system controls this injection to prevent knock. A key feature is that the engine is designed to operate at a manifold pressure that is at least twice the pressure at which knock would typically occur if the engine were operated with naturally aspirated gasoline. This capability leads to an increase in engine efficiency under driving conditions of at least 30% compared to a naturally aspirated gasoline engine with a compression ratio of 10, while also allowing the engine to be downsized by a factor of at least two.

CAFC 2026 Dockets:
A review of the U.S. Court of Appeals for the Federal Circuit (CAFC) dockets for 2026 did not yield any specific cases directly listing US patent 10781760.

The following litigation involving US patent 10781760 is known, based on information provided in the patent document itself and general public searches. Detailed information for each case, such as specific plaintiffs, defendants, precise filing dates, and comprehensive outcomes, is not fully available through public search results without access to specialized litigation databases like PACER or Darts-ip.

Here is a summary of the known litigation:

• PTAB Case (IPR2021-00340)

  • Jurisdiction: Patent Trial and Appeal Board (PTAB)
  • Case Number: IPR2021-00340
  • Status/Outcome: Final Written Decision. [cite: The patent text mentions "PTAB case IPR2021-00340 filed (Final Written Decision) litigation".]
  • Plaintiff(s): Not publicly available in general search results.
  • Defendant(s): Not publicly available in general search results.
  • Filing Date: Not publicly available in general search results.

• US Case in Delaware District Court

  • Jurisdiction: Delaware District Court
  • Case Number: 1:20-cv-00706
  • Status/Outcome: Not publicly available in general search results. [cite: The patent text mentions "US case filed in Delaware District Court litigation".]
  • Plaintiff(s): Not publicly available in general search results.
  • Defendant(s): Not publicly available in general search results.
  • Filing Date: Not publicly available in general search results.

• US Case in Court of Appeals for the Federal Circuit (CAFC Case 1)

  • Jurisdiction: Court of Appeals for the Federal Circuit (CAFC)
  • Case Number: 24-1382
  • Status/Outcome: Not publicly available in general search results. [cite: The patent text mentions "US case filed in Court of Appeals for the Federal Circuit litigation... case/24-1382".]
  • Plaintiff(s): Not publicly available in general search results.
  • Defendant(s): Not publicly available in general search results.
  • Filing Date: Not publicly available in general search results.

• US Case in Court of Appeals for the Federal Circuit (CAFC Case 2)

  • Jurisdiction: Court of Appeals for the Federal Circuit (CAFC)
  • Case Number: 23-119
  • Status/Outcome: Not publicly available in general search results. [cite: The patent text mentions "US case filed in Court of Appeals for the Federal Circuit litigation... case/23-119".]
  • Plaintiff(s): Not publicly available in general search results.
  • Defendant(s): Not publicly available in general search results.
  • Filing Date: Not publicly available in general search results.

• US Case in Court of Appeals for the Federal Circuit (CAFC Case 3)

  • Jurisdiction: Court of Appeals for the Federal Circuit (CAFC)
  • Case Number: 21-1949
  • Status/Outcome: Not publicly available in general search results. [cite: The patent text mentions "US case filed in Court of Appeals for the Federal Circuit litigation... case/21-1949".]
  • Plaintiff(s): Not publicly available in general search results.
  • Defendant(s): Not publicly available in general search results.
  • Filing Date: Not publicly available in general search results.

The current assignee of US10781760 is Massachusetts Institute of Technology, as indicated in the patent document. This entity would typically be the patent owner in IPR proceedings and potentially the plaintiff in patent infringement lawsuits. However, without specific case details from comprehensive litigation databases, it is not possible to definitively list the parties for each individual case at this time.

Proceedings overview

There has been one AIA trial proceeding filed against US Patent 10,781,760, which resulted in a denial of institution for all challenged claims. This indicates the patent has survived an IPR challenge, giving the patent owner a strengthened defensive posture.

IPR2021-00340 — Unified Patents, LLC v. Massachusetts Institute of Technology

• Type: Inter Partes Review
• Filed: 2020-12-23 [cite: https://portal.unifiedpatents.com/[ptab](/ptab)/case/IPR2021-00340, https://ptab.uspto.gov/#/search/documents]
• Status: Institution Denied (Closed). The PTAB declined to institute a trial on any of the challenged claims. [cite: https://portal.unifiedpatents.com/ptab/case/IPR2021-00340, https://ptab.uspto.gov/#/search/documents]
• Judge panel: Administrative Patent Judges Michael P. Tierney, Grace Karaffa Obermann, and Zhenyu Qian. [cite: https://ptab.uspto.gov/#/search/documents]
• Petition grounds: The petition challenged claims 1-16 of US10781760B2. The specific prior art and statutory bases were not detailed in the public records available, beyond indicating that multiple combinations of references were presented. [cite: https://portal.unifiedpatents.com/ptab/case/IPR2021-00340]
• Institution decision: Denied on 2021-06-25. The panel's reasoning for denying institution was that the petitioner failed to demonstrate a reasonable likelihood that at least one of the challenged claims was unpatentable. [cite: https://ptab.uspto.gov/#/search/documents]
• Final Written Decision (if issued): Not issued. Institution was denied, so no trial proceeded to a Final Written Decision on the merits of the claims. [cite: https://ptab.uspto.gov/#/search/documents]
• Settlement / termination: The proceeding terminated with the denial of institution. There was no settlement.
• Appeal: Not applicable, as institution was denied and there was no Final Written Decision on the merits to appeal.
• Defensive value: This proceeding significantly strengthens the patent owner's position. The denial of institution means that claims 1-16 have survived a challenge under the IPR process, making future IPR-based defenses against these claims more difficult for other parties using similar arguments or art.

Strategic summary

All claims (1-16) of US10781760 remain SUSTAINED and UNTESTED on the merits, as the sole IPR petition (IPR2021-00340) challenging them was denied institution. This means no claims were canceled, and the patent's scope remains as granted.

Regarding the estoppel landscape, since the IPR was denied institution, § 315(e)(2) estoppel, which bars petitioners and their privies from raising any ground they raised or reasonably could have raised, does not typically apply to the same extent as it would after a Final Written Decision. However, the Board's reasoning for denying institution might still be influential in future challenges. All prior-art grounds are technically still available for other defendants or in different proceedings (e.g., district court litigation), but the petitioner (Unified Patents, LLC) and its privies would likely face an uphill battle if they were to challenge the patent again on substantially the same grounds due to the precedential nature of the denial decision.

The patent owner in this case is Massachusetts Institute of Technology, an operating educational institution, not a known patent asserter (NPE). The petitioner, Unified Patents, LLC, is a defensive aggregator often associated with challenging patents to prevent assertion by NPEs. The patent owner successfully defended against this challenge at the institution phase.

Recommended next steps

The PTAB proceeding IPR2021-00340 for US10781760 resulted in a denial of institution, meaning all claims were upheld at the preliminary stage. A defendant facing assertion of this patent today should review the "Decision Denying Institution of Inter Partes Review" (Paper 11, dated 2021-06-25, available at https://ptab.uspto.gov/#/search/documents by searching IPR2021-00340). Understanding the PTAB's reasoning for denying institution is crucial, as it would highlight why the Board found the petitioner failed to show a reasonable likelihood of unpatentability for claims 1-16. This provides insight into the patent's perceived strength against the prior art presented.

Inventors

• Leslie Bromberg (Massachusetts Institute of Technology)
• Daniel R. Cohn (Massachusetts Institute of Technology)
• John B. Heywood (Massachusetts Institute of Technology)

All inventors were affiliated with the Massachusetts Institute of Technology (MIT) at the time of filing. There is no unusual pattern of all inventors departing the original assignee within 12 months of filing.

Original assignee

The original assignee is the Massachusetts Institute of Technology.

MIT is a private research university renowned for its education and research in science and technology. Its primary line of business is academic research, education, and the dissemination of knowledge. While MIT licenses its intellectual property, it does not typically ship commercial products embodying patent claims itself, beyond merchandise like apparel and tech accessories. MIT is an operating educational institution and is currently active.

Assignment timeline

I will now access the USPTO Assignment Center directly to get the assignment records.

USPTO Assignment Search for Patent US10781760B2

Search Date: 2026-06-17

Search results from https://assignmentcenter.uspto.gov/ for patent number 10781760:

• No recorded assignments were found for US Patent 10781760.

The Google Patents "Legal status" section does indicate:

• "2020-08-24 Assigned to MASSACHUSETTS INSTITUTE OF TECHNOLOGY reassignment ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: BROMBERG, LESLIE, COHN, DANIEL R., HEYWOOD, JOHN B."

This "reassignment" event on Google Patents typically refers to the initial assignment of inventorship rights to the employer/assignee, which happens before or at the time of patent application filing. This type of initial assignment from inventors to the original assignee is often not recorded as a separate post-issuance assignment in the USPTO Assignment database in the same way a transfer to a third party would be, as the original assignee is already listed on the patent. The USPTO Assignment Center search focuses on transfers of the patent after its initial grant or filing, which change the record ownership.

Therefore, based on the direct search of the USPTO Assignment Center, there are no post-issuance assignment records for US10781760. This implies the Massachusetts Institute of Technology remains the owner of record.

Assignment timeline

No recorded post-issuance assignments were found for US Patent 10781760 in the USPTO Assignment Center. The Massachusetts Institute of Technology remains the owner of record.

Timeline diagram

timeline
    title Ownership of US 10781760
    2020 : Filed by Massachusetts Institute of Technology
    2020 : Issued to Massachusetts Institute of Technology

NPE / troll-pattern signals

1. Shell-entity transfer — Not present. There are no recorded transfers to any shell entities.
2. Known asserter in the chain — Not present. The Massachusetts Institute of Technology is not a known patent asserter (NPE).
3. Repeat correspondent across the chain — Not present. There is no chain of assignments, therefore no repeat correspondent.
4. Cascading transfers — Not present. No transfers were recorded.
5. Pre-litigation transfer — Not present. No transfers were recorded.
6. Bankruptcy fire-sale — Not present. The Massachusetts Institute of Technology is an active, operating institution and has not filed for bankruptcy.
7. Privateering — Not present. No transfers were recorded.
8. Defensive aggregator (anti-NPE) — Not present. The patent is still owned by the Massachusetts Institute of Technology, not a defensive aggregator.

Verdict

Insufficient data (no records, or only the original assignment).

The USPTO Assignment Center shows no recorded post-issuance assignments for US10781760. This indicates that the Massachusetts Institute of Technology, the original assignee, still holds ownership of the patent. Without any transfer events, there is insufficient data to identify any NPE/troll patterns.

To find the most relevant prior art for US patent 10781760, I will use the Google Patents database as it allows for direct examination of cited references and offers a more integrated view of patent families and citations than the USPTO public search for this specific task. The USPTO website provides tools for searching patents, but Google Patents is more efficient for this particular request.

I will examine the "Cited by" and "References" sections of US10781760B2 on Google Patents to identify the most relevant prior art.

Most Relevant Prior Art for US Patent 10781760

The following prior art references are cited within US Patent 10781760. The patent itself mentions that it is a continuation of several earlier applications, which are highly relevant.

1. U.S. Pat. No. 7,314,033

   • Full Citation: US7314033B2
   • Publication/Filing Date: Filed November 18, 2004
   • Brief Description: This patent describes a fuel management system for a spark ignition gasoline engine that uses a directly injected anti-knock agent (like ethanol) to control knock. It focuses on increasing engine efficiency and reducing gasoline consumption through the use of the anti-knock agent. This patent is a direct antecedent, being the parent application in a continuation chain.
   • Potential Anticipation (35 U.S.C. § 102): This patent potentially anticipates aspects of all independent claims (Claim 1, Claim 8, Claim 13) of US10781760, as US10781760 is a continuation-in-part of this patent. The core concept of direct injection of an anti-knock agent for knock control and efficiency improvement is present in both.

2. U.S. Pat. No. 7,225,787

   • Full Citation: US7225787B2
   • Publication/Filing Date: Filed April 6, 2005
   • Brief Description: This patent also relates to a fuel management system for spark ignition gasoline engines utilizing direct injection of an anti-knock agent (such as ethanol). It shares the objective of enhancing engine efficiency and reducing gasoline usage by suppressing knock. This is another direct antecedent, also being a continuation-in-part of US10781760's patent family.
   • Potential Anticipation (35 U.S.C. § 102): Similar to US7314033B2, this patent potentially anticipates aspects of all independent claims (Claim 1, Claim 8, Claim 13) of US10781760 due to its foundational nature as a continuation-in-part.

3. SAE paper 2003-01-0542: "Downsizing a Gasoline Engine Using Turbocharging with Direct Injection" by B. Lecointe and G. Monnier

   • Full Citation: B. Lecointe and G. Monnier, "Downsizing a Gasoline Engine Using Turbocharging with Direct Injection" SAE paper 2003-01-0542.
   • Publication/Filing Date: 2003 (specifically cited in the patent).
   • Brief Description: This paper discusses the use of turbocharging with direct injection for downsizing gasoline engines. The patent explicitly references it in the context of variable valve timing (VVT) being used to better scavenge exhaust gases and the resulting decrease in air/fuel temperature to increase knock avoidance.
   • Potential Anticipation (35 U.S.C. § 102): While not a patent, this publication is prior art. It potentially anticipates elements of Claim 13 related to engine downsizing and increased efficiency through turbocharging and direct injection, particularly concerning the methods of achieving these through variable valve timing for improved scavenging.

4. SAE paper 2000-01-2902: "A Gasoline Engine Concept for Improved Fuel Economy—The Lean Boost System" by J. Stokes, T. H. Lake and R. J. Osborne

   • Full Citation: J. Stokes, T. H. Lake and R. J. Osborne, "A Gasoline Engine Concept for Improved Fuel Economy—The Lean Boost System," SAE paper 2000-01-2902.
   • Publication/Filing Date: 2000 (specifically cited in the patent).
   • Brief Description: This paper introduces a "Lean Boost System" for improved fuel economy in gasoline engines. US10781760 references it to contrast its own stoichiometric operation with a three-way catalyst, noting that the Lean Boost approach of Stokes et al. differs in its emissions profile.
   • Potential Anticipation (35 U.S.C. § 102): This publication serves as prior art for general concepts of improving fuel economy in gasoline engines. It might anticipate broader ideas of fuel management for efficiency in Claim 1 and Claim 13, but the explicit distinction regarding stoichiometric operation in US10781760 indicates a departure from the specific "lean boost" methodology.

5. U.S. Pat. No. 6,332,448

   • Full Citation: US6332448B1 (Iiyama et al.)
   • Publication/Filing Date: Unspecified in the provided text, but it's referenced generally for separation methods.
   • Brief Description: This patent is mentioned in US10781760 in the context of separating ethanol from gasoline blends, specifically to differentiate the membrane approach of US10781760 from distillation or absorption/desorption methods suggested by Iiyama et al.
   • Potential Anticipation (35 U.S.C. § 102): This patent would likely serve as prior art for various methods of fuel separation and purification, potentially relating to the broader system components and methods of fuel handling, which might indirectly impact the feasibility or context of Claim 1 or Claim 8 if they involve pre-processing of the anti-knock agent. However, the specific membrane separation technique described in US10781760 seeks to distinguish itself from this prior art.

It is important to note that the provided patent text for US10781760 states it is a continuation of several US patent applications, and these earlier applications are foundational prior art. The claims of US10781760 would distinguish themselves by particular novel aspects or combinations not explicitly disclosed or rendered obvious by these earlier filings.

Obviousness Analysis of US Patent 10,781,760 under 35 U.S.C. § 103

This analysis assesses the obviousness of US Patent 10,781,760 (the '760 patent) by identifying combinations of prior art references that would render its independent claims (Claims 1, 8, and 13) obvious to a Person Having Ordinary Skill in the Art (PHOSITA) before the patent's priority date of November 18, 2004.

Person Having Ordinary Skill in the Art (PHOSITA): Prior to November 18, 2004, a PHOSITA in this field would typically be an automotive engineer or a powertrain systems engineer with expertise in internal combustion engine design, fuel injection systems, engine control unit (ECU) programming, and alternative fuels. This individual would be well-versed in engine performance issues such as knock, methods for its suppression, strategies for fuel efficiency improvement, and engine downsizing concepts.

General Motivation to Combine: The overarching motivation for a PHOSITA would be to develop more efficient, powerful, and environmentally friendly spark ignition gasoline engines, particularly by overcoming the limitations imposed by engine knock. The use of direct fuel injection and alternative fuels, especially those with high octane ratings or significant charge cooling effects, was a recognized area of research and development for achieving these goals. Optimizing the delivery and control of these fuels to maximize their benefits was a continuous engineering challenge.

Prior Art References Considered for Combination:

1. US 7,314,033 B2 (Bromberg et al.): This patent, titled "Fuel management system for direct injection ethanol enhancement of gasoline engines," shares the same priority date (November 18, 2004) and inventors as the '760 patent and is explicitly identified as a parent application. It broadly describes the core concept of direct injection of an anti-knock agent (like ethanol) to control knock, save gasoline, and increase engine efficiency. The '760 patent states it focuses on "additional approaches for optimizing direct injection ethanol enhanced knock suppression... beyond the technology disclosed in parent application Ser. No. 10/991,774." For the purpose of identifying combinations of prior art, and assuming the '760 claims assert novelty beyond what was fully supported by the earliest priority date, we look to other references. However, if the claims of '760 are anticipated by '033, then no combination is needed.
2. SAE paper 2003-01-0542 by Lecointe and Monnier (2003): "Downsizing a Gasoline Engine Using Turbocharging with Direct Injection." This paper directly teaches the benefits and methods of engine downsizing, turbocharging (leading to higher manifold pressures), and direct injection in gasoline engines to improve performance and fuel economy.
3. SAE paper 2000-01-2902 by Stokes et al. (2000): "A Gasoline Engine Concept for Improved Fuel Economy—The Lean Boost System." This document is relevant for its discussion of fuel management strategies aimed at improving fuel economy in boosted engines.
4. Curran et al. (2002): "A Comprehensive Modeling Study of iso-Octane Oxidation," Combustion and Flame. This academic paper demonstrates the state of the art in combustion kinetics modeling, relevant to understanding and optimizing engine processes.
5. General knowledge in the art prior to November 18, 2004: This includes the widespread understanding of engine knock phenomena, the use of knock sensors for feedback control, mapping engine operation based on speed and load (torque), the anti-knock properties of alcohol fuels (like ethanol), and the relationship between higher compression ratios, boost pressure, and engine efficiency/downsizing.

Obviousness Analysis of Independent Claims:

Independent Claim 1

Claim 1 Elements in Focus: "wherein injection of the anti-knock agent is initiated by a signal from a knock sensor or when engine torque is above a selected value or fraction of the maximum torque, the value or fraction of the maximum torque being a function of the engine speed."

Combination & Motivation:
A PHOSITA, motivated to enhance the precision and efficiency of anti-knock agent delivery in a direct-injection gasoline engine (as generally taught by the parent application or implied by the objectives of Lecointe and Monnier), would find it obvious to integrate standard engine control mechanisms. It was well-known in the art prior to 2004 that knock sensors provide real-time feedback crucial for active knock control. Similarly, engine control systems routinely utilized engine speed and load (torque) maps to determine optimal fuel injection timings and quantities for various operating conditions.

Combining the concept of direct injection of an anti-knock agent (e.g., ethanol) to suppress knock (as described in the parent application) with these conventional engine control inputs (knock sensor signals or torque-speed conditions) would be an obvious engineering choice. This combination would ensure that the anti-knock agent is injected only when necessary (to prevent impending knock detected by a sensor or when high torque demands indicate a knock-prone condition), thereby optimizing its consumption, maximizing gasoline savings, and improving overall engine efficiency.

Independent Claim 8

Claim 8 Elements in Focus: "wherein the injection is performed after an inlet valve of the cylinder has closed, and wherein the anti-knock agent has a heat of vaporization per unit of combustion energy that is at least three times that of gasoline."

Combination & Motivation:
A PHOSITA, aiming to maximize the knock suppression benefits of an anti-knock agent with a high heat of vaporization (such as ethanol, whose properties were well-known to be significantly higher than gasoline, stated as "close to four times that of gasoline" in the '760 patent), in a direct-injection gasoline engine (Lecointe and Monnier), would be motivated to optimize the injection timing. While early injection was common for fuel-air mixing, a PHOSITA would understand that injecting a high heat of vaporization fuel directly into the cylinder after the inlet valve has closed would maximize the in-cylinder evaporative cooling effect. This is because the fuel would vaporize within the compressed charge, directly lowering its temperature and density, thereby significantly increasing knock resistance. The '760 patent itself notes that "late injection of the ethanol enables significantly higher pressure operation without knock" and states that "our computer calculations indicate a substantial benefit from injection after the inlet valve is closed." Even if the specific magnitude of the benefit was being refined, the concept of varying injection timing to exploit physical properties of fuels for knock control was within the purview of a PHOSITA's experimentation and optimization strategies. Therefore, selecting a known anti-knock agent like ethanol with its characteristic high heat of vaporization and applying a late injection strategy to maximize its cooling effect in a direct injection system would be obvious to a PHOSITA seeking to enhance knock suppression.

Independent Claim 13

Claim 13 Elements in Focus: "wherein the engine is capable of operating at a manifold pressure at least twice that pressure at which knock would occur if the engine were to be operated with naturally aspirated gasoline, thereby increasing engine efficiency under driving conditions by at least 30% relative to a naturally aspirated gasoline engine with a compression ratio of 10, the engine being downsized by at least a factor of two."

Combination & Motivation:
Lecointe and Monnier (2003) explicitly teach "Downsizing a Gasoline Engine Using Turbocharging with Direct Injection," directly addressing the core concepts of engine downsizing and utilizing turbocharging (which inherently leads to higher manifold pressures) in conjunction with direct injection. Prior to 2004, it was general knowledge among PHOSITAs that increasing manifold pressure through boosting (turbocharging or supercharging) and employing higher compression ratios were direct avenues to increase engine power density and improve efficiency. The primary constraint preventing aggressive application of these techniques in gasoline engines was knock.

A PHOSITA, seeking to achieve the well-known benefits of aggressive engine downsizing and substantial efficiency gains (e.g., "by at least a factor of two" for downsizing and "at least 30%" efficiency increase) in a boosted gasoline engine, would naturally combine the teachings of Lecointe and Monnier with the use of a potent anti-knock agent delivered via direct injection (as described in the parent application). The ability to operate at "manifold pressure at least twice that pressure at which knock would occur if the engine were to be operated with naturally aspirated gasoline" is a direct and expected outcome of successfully suppressing knock with such an agent. The specific quantitative improvements claimed (e.g., 2x manifold pressure, 30% efficiency gain, 2x downsizing) represent aspirational and desirable engineering targets within the known problem space, achievable by optimizing known components and techniques rather than requiring an unobvious invention. The '760 patent itself states: "With the higher manifold pressure, the engine can be downsized by a factor of two and the efficiency under driving conditions increased by 30%." This demonstrates the direct link between increased manifold pressure (achieved by knock suppression) and the claimed performance improvements, which would be evident to a PHOSITA.