Derivative works — US Patent 7513238

Defensive Disclosure Document for US Patent 7513238

Patent Title: Directly injecting internal combustion engine
Current Date: April 26, 2026

This document presents a series of derivative variations and combination prior art scenarios for US Patent 7513238, "Directly injecting internal combustion engine." The objective is to proactively establish prior art that renders future incremental improvements or obvious variations in this technical domain non-novel or obvious, thereby limiting potential patentability for competitors. The focus is on expanding the technical disclosure beyond the explicit scope of the granted claims, particularly Claim 1, by exploring alternative materials, operational parameters, cross-domain applications, integration with emerging technologies, and inverse/failure modes.

Derivative Variations

1. Material & Component Substitution

Derivative 1.1: Functionally Graded Piston with Ceramic Recess Liner

Enabling Description:
This derivative envisions a directly injecting internal combustion engine wherein the piston (6) is fabricated using functionally graded materials (FGMs), specifically a graded transition from an aluminum-silicon alloy base to a high-temperature resistant ceramic-matrix composite (CMC) layer at the piston crown (adjacent to the combustion space 5). The piston recess (10) itself, including the central elevation (11) and the adjoining planar surface (13), is further coated or lined with a dense, plasma-sprayed zirconia (ZrO2) ceramic. This ceramic liner provides enhanced thermal insulation and wear resistance, allowing for higher combustion temperatures and reducing heat transfer to the piston body. The radius (14) connecting the elevation (11) to the adjoining surface (13) is precisely machined into the ceramic liner to maintain the fuel jet (9) distribution characteristics, even under extreme thermal cycling. The FGM structure is achieved via advanced additive manufacturing techniques like selective laser melting (SLM) for the metallic base and subsequent directed energy deposition (DED) for the ceramic-rich crown, ensuring a robust metallurgical bond and thermal gradient management.

classDiagram
    class Engine {
        +Cylinder
        +CombustionSpace
        +InjectionNozzle
    }
    class Piston {
        +FGM_Structure
        +Recess(CeramicLiner)
    }
    class InjectionNozzle {
        +FuelInjection
    }
    Piston --> Engine : OscillatesIn
    Engine --> Piston : Contains
    Piston --* InjectionNozzle : InteractsWith
    Piston : PistonRecess(10)
    Piston : Elevation(11)
    Piston : Surface(13)
    Piston : Radius(14)
    PistonRecess "1" *-- "1" CeramicLiner : lined with
    CeramicLiner : Zirconia (ZrO2)
    Piston "1" *-- "1" FGM_Structure : composed of
    FGM_Structure : Al-Si to CMC gradient

Derivative 1.2: Piezoelectric Multi-Orifice Nozzle with Variable Spray Angle

Enabling Description:
This variation features a directly injecting internal combustion engine equipped with a piezoelectric multi-orifice injection nozzle (7). Instead of fixed orifices (8), the nozzle incorporates an array of independently actuatable micro-piezoelectric elements, each controlling a sub-millimeter orifice. This allows for dynamic, real-time adjustment of the overall injection angle (α), fuel pressure, and spray pattern (e.g., number of active orifices, individual jet penetration). The piston recess (10) geometry, including the elevation (11) and the connecting radius (14) to the planar surface (13), is designed to optimally interact with this variable spray. For instance, an early injection jet (9a) might utilize a wider spray angle (up to 120°) to ensure impingement on the radius (14) and broad distribution, while a late injection jet (9b) could employ a narrower, more penetrating spray (down to 50°) to precisely target the planar surface (13) with its ascending gradient. The piezoelectric actuators allow for injection events with sub-millisecond precision, enabling highly flexible fuel-air mixing strategies to adapt to varying engine loads and speeds.

flowchart TD
    A[Engine Control Unit (ECU)] --> B{Piezoelectric Injection Nozzle}
    B -- Controls --> C[Multiple Micro-Orifices]
    C -- Delivers --> D(Injection Jet)
    D --> E[Piston Recess]
    E -- Distributes Fuel --> F[Elevation Direction]
    E -- Distributes Fuel --> G[Recess Edge Direction]
    B -- Adjusts --> H{Spray Angle & Pattern}
    H -- Adapts To --> I[Engine Load/Speed]
    E -- Geometry Includes --> J[Central Elevation (11)]
    E -- Geometry Includes --> K[Surface with Radius (13, 14)]

2. Operational Parameter Expansion

Derivative 2.1: Micro-Scale Engine for Portable Power Generation

Enabling Description:
This derivative scales down the directly injecting internal combustion engine to a micro-scale, suitable for portable power generation or micro-UAV propulsion. The single cylinder has a bore diameter in the range of 1-5 mm, and the piston (6) executes an oscillating movement at extremely high frequencies (e.g., 50,000-200,000 RPM). The piston recess (10), elevation (11), and adjoining surface (13) with its radius (14) are fabricated using MEMS (Micro-Electro-Mechanical Systems) techniques, possibly from silicon or silicon carbide. The fuel injection nozzle (7) is a micro-injector, potentially utilizing electrostatic or thermal inkjet principles to deliver pico-liter quantities of fuel (e.g., hydrogen, methanol) with sub-microsecond precision. The small dimensions necessitate precise control over surface tension effects and laminar/turbulent flow transitions within the combustion space (5). The primary function of distributing early and late injection jets is maintained, but the characteristic lengths and timescales are reduced by several orders of magnitude, requiring novel approaches to mixture formation and ignition in such confined volumes.

graph TD
    A[Micro-Engine System] --> B[Micro-Cylinder (1-5mm bore)]
    B --> C[Micro-Piston (6)]
    C --> D[Micro-Piston Recess (10)]
    D -- Includes --> E[Micro-Elevation (11)]
    D -- Includes --> F[Micro-Surface (13)]
    F -- Connected Via --> G[Micro-Radius (14)]
    B --> H[Micro-Injection Nozzle (7)]
    H -- Injects Pico-liter Fuel --> I[Micro-Combustion Space (5)]
    I -- Forms --> J[Micro-Injection Jet (9)]
    J --> D
    C -- Operates At --> K[High Frequencies (50-200k RPM)]
    A -- Fabrication Using --> L[MEMS Techniques]

Derivative 2.2: Ultra-High Pressure Combustion with Adaptive Recess Geometry

Enabling Description:
This derivative explores the directly injecting internal combustion engine operating at ultra-high peak combustion pressures, potentially exceeding 300 bar, characteristic of advanced diesel or homogeneous charge compression ignition (HCCI) concepts. To manage these extreme pressures and ensure optimal fuel-air mixing, the piston recess (10) features an adaptive geometry. The central elevation (11) and/or the planar surface (13) are equipped with embedded, hydraulically or electromagnetically actuated micro-elements capable of dynamically altering their shape or position during the compression and combustion strokes. For example, the elevation (11) could retract slightly during late injection to modify the impingement angle for the jet (9b), or the radius (14) could expand to adjust the deflection of early jets (9a). These actuators are controlled by a high-speed engine management system that receives feedback from in-cylinder pressure and temperature sensors, allowing for real-time optimization of combustion characteristics under varying load conditions. The piston itself is constructed from high-strength superalloys (e.g., Inconel) or high-strength steel to withstand the immense forces.

stateDiagram-v2
    state "Engine_Start" as Start
    state "Compression_Stroke" as Comp
    state "Fuel_Injection" as Inject
    state "Combustion_Event" as Combust
    state "Adaptive_Recess_Adjustment" as Adapt
    state "Feedback_Loop" as Feedback
    state "Optimized_Combustion" as OptCombust

    Start --> Comp : Engine initiated
    Comp --> Inject : TDC approach
    Inject --> Combust : Ignition
    Inject --> Adapt : Simultaneous adjustment
    Combust --> Feedback : Sensors detect P, T
    Feedback --> Adapt : ECU commands adjustments
    Adapt --> Inject : Adjusts for next cycle
    Combust --> OptCombust : Achieves desired outcome

    Adapt --> RecessElevationAdj[Adjust Elevation (11)]
    Adapt --> RecessSurfaceAdj[Adjust Surface (13)/Radius (14)]
    RecessElevationAdj --> Actuators[Hydraulic/Electromagnetic Actuators]
    RecessSurfaceAdj --> Actuators
    Actuators --> PistonRecess[Piston Recess Geometry]

3. Cross-Domain Application

Derivative 3.1: Fuel Injection in a Continuous Flow Chemical Reactor

Enabling Description:
Applying the principles of US7513238 to a continuous flow chemical reactor, the "combustion space" (5) becomes the reaction chamber, and the "piston recess" (10) is a stationary or rotating internal baffle or flow guide within the reactor. A "reactant injection nozzle" (7) introduces a precise stream of reactant 'A' (analogous to fuel) into the reaction chamber. The baffle's geometry includes a central "impingement elevation" (11) and an "adjoining distribution surface" (13) connected by a "flow redirection radius" (14). This design ensures that an early reactant jet (e.g., a liquid or gas stream with high momentum) impinges on the surface via the radius, distributing reactant 'A' both towards the elevation (promoting localized mixing or reaction) and towards the edge of the baffle (facilitating wider dispersion and mixing with other reactants in the main flow). A later reactant jet, or one with lower momentum, impacts the planar surface, ensuring its distribution and preventing a direct, unmixed stream. This optimizes reactant mixing, controls reaction kinetics, and prevents localized hot spots or incomplete reactions. This could be used for catalytic processes, polymerization, or emulsification.

flowchart LR
    A[Reactant 'A' Supply] --> B(Reactant Injection Nozzle)
    B -- Injects Jet --> C[Chemical Reactor Chamber]
    C --> D[Internal Baffle / Flow Guide]
    D -- Geometry: --> E[Central Impingement Elevation (11)]
    D -- Geometry: --> F[Adjoining Distribution Surface (13)]
    F -- Connected by --> G[Flow Redirection Radius (14)]
    B -- Early Jet --> F
    B -- Late Jet --> F
    F -- Distributes Reactant 'A' --> H[Localized Mixing (Elevation Direction)]
    F -- Distributes Reactant 'A' --> I[Wider Dispersion (Baffle Edge Direction)]
    H & I --> J[Optimized Reaction Kinetics]

Derivative 3.2: Particulate Dispersion System for Pharmaceutical Manufacturing

Enabling Description:
In pharmaceutical manufacturing, the controlled dispersion of active pharmaceutical ingredients (APIs) or excipients into a carrier gas or liquid stream is critical. This derivative utilizes the piston recess geometry for a particulate dispersion system. The "cylinder" is a mixing chamber, and the "piston" is a stationary or vibrating dispersion element. The "injection nozzle" (7) delivers a stream of fine pharmaceutical powder (e.g., micronized drug particles) or a liquid suspension. The "dispersion element" has a central "deflection cone" (11) and an "impingement surface" (13) connected by a "scattering radius" (14). An early, high-momentum particulate stream (9a) impinges on the scattering radius (14), causing it to be distributed both towards the apex of the cone (facilitating agglomerate breakup) and towards the outer edge of the impingement surface (promoting uniform dispersion within the carrier medium). A later, lower-momentum stream (9b) also impinges the planar impingement surface (13), ensuring its controlled scattering. This mechanism prevents particle agglomeration, ensures uniform particle size distribution, and optimizes mixing efficiency for applications like dry powder inhalers, tablet granulation, or aseptic filling processes.

graph TD
    A[Raw Material (Powder/Suspension)] --> B(Delivery Nozzle)
    B -- Injects Stream --> C[Mixing Chamber]
    C --> D[Dispersion Element]
    D -- Features --> E[Deflection Cone (11)]
    D -- Features --> F[Impingement Surface (13)]
    F -- Connected by --> G[Scattering Radius (14)]
    B -- Early Stream --> G
    B -- Late Stream --> F
    F -- Scatters Particles --> H[Agglomerate Breakup (Cone Direction)]
    F -- Scatters Particles --> I[Uniform Dispersion (Surface Edge Direction)]
    H & I --> J[Optimized Particle Distribution]

4. Integration with Emerging Technologies

Derivative 4.1: AI-Optimized Real-time Injection and Recess Cooling Control

Enabling Description:
This derivative integrates AI-driven optimization into the directly injecting internal combustion engine. The engine is equipped with an array of IoT sensors (e.g., in-cylinder pressure transducers, exhaust gas temperature and NOx sensors, piston surface thermocouples, injection nozzle temperature/wear sensors). These sensors provide real-time data to an Artificial Intelligence Engine Control Unit (AI-ECU). The AI-ECU, utilizing deep learning algorithms trained on extensive combustion datasets, dynamically adjusts the fuel injection parameters (timing, pressure, duration, multi-pulse strategy) and a newly introduced active cooling system for the piston recess (10). This active cooling, potentially using micro-channels within the piston (6) supplied with a circulating coolant, is precisely controlled to maintain optimal surface temperatures on the elevation (11) and adjoining surface (13) for fuel film evaporation and reduced coking. The AI predicts the optimal "virtual" recess geometry and injection strategy in real-time to maximize combustion efficiency and minimize emissions across the entire operating map, effectively learning and adapting to dynamic conditions and even engine wear.

sequenceDiagram
    participant S as IoT Sensors
    participant A as AI-ECU (Deep Learning)
    participant N as Injection Nozzle
    participant P as Piston Recess (w/ Active Cooling)
    participant C as Combustion Space
    participant E as Exhaust System

    loop Real-time Optimization
        S->>A: Send raw sensor data (P, T, NOx, etc.)
        A->>A: Process data & predict optimal parameters
        A->>N: Adjust injection (timing, pressure, pulses)
        A->>P: Control active recess cooling
        N->>C: Inject fuel
        P->>C: Shape fuel distribution
        C->>E: Combustion & emissions
        E->>S: Provide feedback (NOx, Temp)
    end

Derivative 4.2: IoT-Enabled Predictive Maintenance with Blockchain-Verified Emissions

Enabling Description:
This derivative enhances the directly injecting internal combustion engine with a comprehensive IoT and blockchain system for operational transparency and compliance. Each engine is equipped with an embedded IoT module that collects granular data from sensors within the combustion space (5), including precise fuel injection events (from nozzle 7), piston movement, and particularly, actual emissions data (CO2, NOx, Particulate Matter) from the exhaust. This data is timestamped, cryptographically hashed, and transmitted to a private blockchain network at regular intervals. The piston recess (10) design, with its specific elevation (11) and distribution surface (13), contributes to a documented combustion profile. The blockchain immutably records not only operational performance but also verifiable emissions reductions achieved through the engine's optimized design. This system facilitates predictive maintenance by identifying anomalous operational patterns on-chain and provides a transparent, tamper-proof record for carbon credit verification, regulatory compliance, and fuel provenance tracking, ensuring that the engine's design benefits are quantifiable and auditable.

graph TD
    A[Engine (US7513238)] --> B[IoT Sensors (Fuel, Emissions, Piston)]
    B --> C[IoT Gateway/Module]
    C -- Encrypt & Hash --> D{Blockchain Network}
    D -- Immutable Records --> E[Verified Emissions Data]
    D -- Immutable Records --> F[Operational Performance Logs]
    D -- Immutable Records --> G[Fuel Provenance]
    E --> H[Carbon Credit Verification]
    E --> I[Regulatory Compliance]
    F --> J[Predictive Maintenance Alerts]
    J --> K[Service Center]

5. The "Inverse" or Failure Mode

Derivative 5.1: Fail-Safe Fuel Diversion System for Engine Knock Mitigation

Enabling Description:
This derivative focuses on a fail-safe mode for the directly injecting internal combustion engine to mitigate severe engine knock or pre-ignition events. Upon detection of critical knocking (via an acoustic sensor array and pressure oscillations in the combustion space 5), the injection nozzle (7) and the piston recess (10) collaborate to execute a controlled fuel diversion. The nozzle (7) rapidly reconfigures its spray pattern (e.g., using a variable-geometry orifice or multi-pulse injection with altered angles) to direct the fuel jet (9) away from the typical impingement points on the radius (14) and planar surface (13). Instead, the fuel is intentionally directed towards a cooler, less reactive "diversion zone" on the piston crown (6) outside the primary recess, or towards the cylinder wall. Simultaneously, micro-actuators within the piston recess (10) might temporarily flatten the elevation (11) or alter the gradient of surface (13) to facilitate rapid quenching of any nascent flame fronts or to spread the fuel thinly, preventing uncontrolled combustion propagation and allowing for a safe engine shutdown or transition to a limp-home mode.

stateDiagram-v2
    state "Normal Operation" as Normal
    state "Knock Detected" as Knock
    state "Initiate Diversion" as Diversion
    state "Fuel Rerouted" as Rerouted
    state "Piston Recess Mod" as RecessMod
    state "Safe Shutdown/Limp-Home" as SafeMode

    Normal --> Knock : Critical Knock Detected
    Knock --> Diversion : Trigger Fail-Safe
    Diversion --> Rerouted : Nozzle alters spray
    Diversion --> RecessMod : Piston actuators modify recess
    Rerouted --> SafeMode : Fuel away from hot spots
    RecessMod --> SafeMode : Quench/Spread fuel
    SafeMode --> Off : Engine Shutdown

Derivative 5.2: Adaptive Low-Emissions Mode for Degraded Engine Operation

Enabling Description:
This derivative describes an adaptive low-emissions mode for the directly injecting internal combustion engine, specifically tailored for scenarios where engine components (e.g., partially clogged fuel injector, degraded sensor) are operating sub-optimally. In this mode, the engine's control unit (ECU) identifies the degraded component via diagnostics. Instead of full shutdown, the system dynamically adjusts the fuel injection strategy and leverages the piston recess (10) geometry to maintain acceptable emissions levels, albeit with reduced power. For example, if an injector orifice is partially blocked, the ECU might adjust the injection timing to ensure the available fuel jet (9) still optimally impinges the radius (14) or planar surface (13) for distribution, compensating for altered jet momentum or angle. Alternatively, the engine could operate exclusively with very early injection points (9a), relying heavily on the radius (14) for maximum distribution, to promote more homogeneous charge conditions and reduce particulate matter, even if it compromises peak power. This mode prioritizes emissions compliance and engine longevity over maximum performance, allowing for continued, albeit limited, operation until repairs can be made.

flowchart TD
    A[Engine Control Unit (ECU)] -- Detects --> B{Degraded Component / Sub-optimal Operation}
    B -- Activates --> C[Adaptive Low-Emissions Mode]
    C -- Adjusts --> D[Fuel Injection Strategy]
    C -- Optimizes Interaction with --> E[Piston Recess (10)]
    D --> F[Compensate for Clogged Injector]
    D --> G[Prioritize Early Injection (9a)]
    E --> H[Leverage Radius (14) for Max Distribution]
    E --> I[Ensure Impingement on Surface (13)]
    F & G & H & I --> J[Reduced Emissions]
    J --> K[Lower Power Output]
    J --> L[Continued Limited Operation]

Combination Prior Art Scenarios with Open-Source Standards

This section identifies scenarios where US Patent 7513238, or derivatives thereof, could be combined with existing open-source standards to further expand the scope of prior art.

US7513238 + OpenFOAM (Open Field Operation and Manipulation):
Combining the specific piston recess geometry (elevation (11), adjoining surface (13), and radius (14)) and the fuel injection strategies of US7513238 with detailed Computational Fluid Dynamics (CFD) simulations performed using the open-source software OpenFOAM. Engineers can use OpenFOAM to model the entire combustion process, including the interaction of the injection jet (9) with the piston recess (10), the resulting fuel-air mixing, and subsequent combustion events. This involves creating precise mesh geometries of the combustion chamber and piston, implementing sophisticated multiphase flow and reaction chemistry models, and simulating the impact of varying injection parameters (angle, pressure, timing) on the fuel distribution. The simulations, openly available through OpenFOAM case studies or community forums, would demonstrate the "obviousness" of optimizing such geometries for improved mixing and combustion efficiency across a range of operating conditions, considering the known principles described in US7513238.
US7513238 + OPC UA (Open Platform Communications Unified Architecture):
Integrating a directly injecting internal combustion engine, as described in US7513238, with an industrial control system utilizing the open-source OPC UA standard for data exchange. IoT sensors within the engine (e.g., in-cylinder pressure, fuel injection parameters, exhaust gas composition) would publish their data as OPC UA nodes. An OPC UA client application (e.g., a Supervisory Control and Data Acquisition (SCADA) system or a process control system) would subscribe to this data to monitor engine performance, diagnose faults, and potentially issue control commands (e.g., adjust injection timing within pre-defined limits) to optimize the engine's operation. This would demonstrate that connecting such a specialized engine to a standardized, open industrial communication framework for monitoring and control is a straightforward application of known technologies, rendering remote monitoring and control aspects "obvious."
US7513238 + Project Jupyter (Jupyter Notebooks):
Utilizing Project Jupyter notebooks as an open-source platform for documenting, sharing, and executing scientific and engineering analyses related to the directly injecting internal combustion engine of US7513238. Researchers and developers could create Jupyter notebooks containing Python code (e.g., using libraries like NumPy, SciPy, Matplotlib) to analyze experimental data obtained from engines with the described piston recess geometry. This would include processing pressure traces, analyzing emission spectra, visualizing fuel spray patterns, and performing statistical analysis on combustion efficiency or pollutant formation. The notebooks could also incorporate explanatory text, equations, and interactive visualizations, serving as open documentation of research findings and demonstrating the "obviousness" of applying standard data analysis and visualization tools to optimize the performance of such engine designs, and for sharing the insights gained from the specific interaction between the fuel jet and piston recess.