Engine Emissions Control System Green Engine Development

Abstract

High Temperature application Linear Actuator with control system to regulate emissions in an internal combustion engine through variable valve opening and valve duration.

Description

BACKGROUND

Differences from prior art include high temperature linear actuators capable of high effort per square inch and high precision moving magnet configuration. This patent also utilizes Rules Based Software processing which further makes this unique. This design centers on manufacturability and cost effective applications to further progress green engine technology. This system replaces the camshaft, lifters, pushrods, rocker arms, and valve springs on standard non overhead cam engines. On overhead cam engines, this replaces the camshaft and valve springs.

Prior Art on motion controllers include universal style controllers offered at numerous companies but are not application specific for valve control including velocity, force, cost, and precision all in one package. Some companies offer packages that are precise but not cost effective (greater than $50,000 per valve). This is not acceptable for this application. Many companies offer controllers that control only certain types of linear actuators that don't have the required precision. Still other companies offer controllers that have too much functionality or control logic or cable interfaces that are not important for this application.

Therefore this application requires a specific controller that interfaces correctly with no built in extraneous functionality.

Prior Art on Rules Based Software (controlling logic) is non existent. The only related down revision type is the inferior Table Based approach to logic processing which is limited in speed and output control.

Prior art of linear actuators do not meet our requirements so a new actuator has been designed to withstand cylinder combustion chamber temperatures and position valves with speed and accuracy required. This is an application of actuators where velocity and position will be constantly varied. RBE is able to control this variability, but prior art linear actuators are not. Prior art has too large an envelope for mounting to a cylinder head. Prior art are too expensive to be used in this application. Therefore, we designed a compact, cost effective solution for this application. Spatial envelope is 4 inches long 1.5″ in diameter. Cost is $1000 per set.

Advantages. A series of high temperature linear actuators with a controller and a computer are used with intake and exhaust valves of an internal combustion engine. This is intended to reduce emissions by utilizing a closed loop feedback system to the system controller from multiple inputs and providing multiple outputs utilizing a Rules Based Software for processing inputs and creating outputs. This invention is intended for green energy related applications where linear actuators with a total engine control system may be utilized for higher engine efficiency and higher gas mileage resulting in reduction of greenhouse emissions. Advantages and applications include all fuel type engines including but not limited to: diesel, natural gas, biofuel, propane and gasoline. There are a number of possible engine applications that can be programmed to optimization. A few applications are emissions optimization, idle duration (default), torque, and horsepower.

The computer logic consists of a Rules Based Software processing which is system that is able to acquire constant inputs from multiple sensors, process at high speeds, and create output signals to the valves controlling duration and stroke. There is a huge amount of inputs that the computer logic is able to process, which is unlike most logic computers that are limited to a low number of inputs. Also, using Rules Based Software processing instead of Table Based processing, the outputs are entirely more exact, since it's done through functions instead of table value references. This system creates a higher level of granularity that has not been applied to the combustion engine. It can be compared to calculus equations to compute the length of an irregular curve by summarizing small contributions to get an exact length of the curve. This computer configuration further increases this engines efficiency.

There is no backlash in utilizing linear actuators, which improves accuracy and ease of installation. Since linear actuators are designed to allow for alignment tolerances, misalignment produces no decreased performance. Velocity speeds are over 8 meters per second or 300 inches per second. Reliability is extremely long term since there is only two parts involved with only one of them moving. This simplicity improves reliability greatly. There is also no wear or maintenance. Since there are no contacting points there is decreased friction and subsequently decreased wear.

The ultimate goal of this system is to optimize the duration and stroke to bring greenhouse emission levels to zero. Gases include hydrocarbons, carbon monoxide, and oxides of nitrogen. Through constant Rules Based processing, the emissions would be minimized no matter the age of the engine. The settings would adjust for conditions including wear, altitude, load, speed, or fuel.

Summary-High Temperature application Linear Actuator with control system to regulate emissions in an internal combustion engine through variable valve opening and valve duration.

DRAWINGS AND FIGURES

Detailed Description

• • 1. First Embodiment—FIGS. 1-4
    • There are three main areas of interest of the first embodiment: the electromechanical motor, the controller, and the computer. See FIG. 1.
    • a) The electromechanical motor, see FIG. 2, consists of a high temperature DC linear motor non commutated (LMNC) which is the linear actuator. There are environmental conditions that have been met including temperature and pressure. The LMNC has been designed for the requirements of forward velocity, return velocity, encoding, cycle times and B-10 lifespan (10,000 hour lifespan). There is one electromechanical motor assembly for each intake and one for exhaust valve and is located in the cylinder head above the combustion cylinder, replacing the typical cam actuated valves. This linear actuator valve opens from a digital signal in small steps and closes in a series of steps: fast then slow. The valve guide shown in FIG. 2 represents the cylinder head that the valve fits into, which is removed for clarity.
    • b) The controller is a potted system comprising of a PCA controller board with both passive and active components. There are three connections to the controller: one to the electromechanical motors, one to the power source, and one to the computer. The first connection from the controller is to the electromechanical motors through a High Temperature rated power harness. The second connection from the controller is to the available power source. The controller is voltage automatic sensing. The third connection from the controller to the computer is through an input/output harness.
    • c) The Accelerated Processing Unit (APU) computer has two functions: receive inputs and transmit outputs. The inputs include voltage, ground, and crank trigger. The outputs include valve timing and valve stroke. This is the heart of the patent: variable valve duration and stroke. By varying duration and stroke of each individual valve while integrating electronic fuel injection and ignition spark timing, engine efficiency increases dramatically. Rules Base Software (RBS) is a software program that runs on the APU.

Detailed Description of Parts

a. Linear actuator design. See FIG. 2. High temperature DC linear motor non commutated servo motors provide constant force over the full stroke. Strokes can be small with very fast response because of a less than one millisecond electric time constant. This linear motor operates at very high speeds without cogging or force ripple with infinite resolution, which separates this total design from other variable cam timing designs since the stroke is variable to infinite resolution. Variable cam timing only changes the timing not the stroke. This design does both with infinite settings based upon closed loop operation. Closed loop operation couples the linear motor with feedback sensors, motor control and motion controller, along with an APU capable of very high processing speeds which replaces the CPU.

b. Controller in detail. One custom motion controller is used to control all linear actuators by sending logic signals from APU.

c. Sensors in detail. Crank trigger relates timing to APU. Location is at crank with a hall effect sensor.

d. Power input can be any value. 12 volts, 24 volts, 40 volts or other.

e. APU takes the place of the CPU. APU is the Accelerated Processing Unit. Simulation to emulate system. Uses a fusion chip from AMD which is a next generation chip allows 3D simulation.

f. RULES BASED SOFTWARE assumptions, usage and basic terminology See FIG. 4.

General Approach: We are using Input Parameters to determine Output Signals by defining Business Objects, Business Rules and Process Equations. The Process Equations gives the Output Signals.

Rules Based Software (RBS) possesses Input Parameters, Business Objects,

Business Rules and Processes.

• • 1. Input Parameters—Value Lists
  • 2. Business Objects—Variables for Business Rules.
  • 3. Business Rules—Guidelines
  • 4. Processes are outputs. Equations of Values governed by Objects and Rules producing outputs.

RBE relates Inputs to Outputs to define pathway that occurs in between them.

General development starts with a list of Values then it moves to Business Objects then it moves to Business Rules and provides the complex Processes by which the linear actuator motion is governed. This is one way this patent is different: it uses Rules Based Software instead of current Table Based logic.

Parameters—Inputs-Constant Value or Computed Function

• • 1. EGT (Exhaust Gas Temperature)—Real Time
  • 2. Crank Trigger (Crank Position)
  • 3. Exhaust Emission Levels (to zero) as closed loop input dictates
  • 4. Throttle Position
  • 5. Oxygen Sensor
  • 6. Engine Temperature
  • 7. Mass Air Flow
  • 8. Intake
  • 9. Exhaust
  • 10. Voltage
  • 11. Ground
  • 12. RPM revolutions per minute of engine
  • 13. Initialization of valve positions. This is the closed position (origin) of each valve.
  • 14. Other initializations.

RBS controls Valve Motion In Regards To:

• • 1. Duration
  • 2. Stroke
  • 3. Velocity
  • 4. Acceleration
  • 5. Timing

RBS is capable of maximum 750,000 events per second currently.

Below is expansion of terms:

Input Parameters

• • Value Lists (Types of Values)—
    • 1. Characters (letters, numerical digits, common punctuation marks, carriage return, tab that get combined into strings)
    • 2. Float (like scientific notation)
    • 3. Integer (whole numbers)
    • 4. String (finite sequence of symbols that are chosen from a set or alphabet)

Business Objects

• • Variables for Business Rules. Does nothing itself but holds a set of instance variables or properties. This holds name, identifier, start date and kind.

Business Rules

• • Guidelines—Boolean Expression having one of two values, such as True or False, less than or greater than, yes or no.

Processes—Equations

• • Equations of Values governed by Objects and Rules producing outputs.

Output Signals

• • Signals sent from APU to motion controller.

2. Operation—First Embodiment.

The invention is to control a valve. It operates as follows:

• • 1. The valve begins at closed position.
  • 2. The valve is opened to a variable stroke distance at specified velocity and acceleration. This distance, velocity and acceleration will change depending on a number of Input Parameters.
  • 3. The valve is held open at distance for a specified amount of time. This value will change depending on Input Parameters.
  • 4. The valve is closed at specified velocity and acceleration. Just before the valve seats (returns to closed position) the velocity and acceleration will change to prevent damage to valve, seat, and actuator.
  • 5. The valve is held at closed position.

From this, comes optimization which depends on application, which can be emissions, horsepower, or other user programmable value.

These are the signals that are sent to the motion controller for Valve Motion

• • 1. Stroke in inches from closed to opened position
  • 2. Velocity in inches per second from closed to opened position
  • 3. Acceleration in inches per second² from closed to opened position
  • 4. Duration in seconds to hold valve open
  • 5. Stroke in inches from opened to closed position from origin
  • 6. Velocity in inches per second from opened to closed position
  • 7. Acceleration in inches per second² from opened to closed position
  • 8. Duration in seconds to hold valve closed and open

General motion is at 6000 RPM that there are 12,800 events. 720 degrees being 1 cycle, 2 valves open, hold, and close per cylinder.

Specifications and requirements for valve and linear actuator includes:

• • 1. heat transfer between face of valve and valve stem (conduction) and heat transfer between valve stem and linear actuator coil (convection) regulated to operating temperatures.
  • 2. Acceleration of valve=320 ft/s² (98.1 m/s²)
  • 3. Travel of valve (stroke)=0.5″ (12.7 mm) maximum
  • 4. Velocity of valve=300 in/s (7.62 m/s)
  • 5. Time to complete stroke=20-30 milliseconds
  • 6. Cooling approach is convection and conduction with fluid flow.
  • 7. Temperature of engine: 230 degrees Celsius or 446 degrees Fahrenheit.
  • 8. Compression ratio=8.5:1 standard V-8
  • 9. Tailpipe exhaust emissions typical:
    • i. (HC) Hydrocarbon (11.95 PPM) to zero
    • ii. (CO) Carbon Monoxide (6.3 PPM) to zero
    • iii. (NOX) Oxides of Nitrogen (5.5 PPM) to zero
    • iv. (CO2) Carbon (1.207 PPM)
    • v. (O) Oxygen (0.2 PPM)
  • 10. Noise measured in decibels to a minimum.

Acceleration can be up to 320 feet per second squared (98 meters per second squared) which is ten G's. These actuators are highly accurate. With the correct encoder, accuracy will be 0.0001 inch per foot (2.5 microns per 300 meters). Repeatability is also dependent upon encoder selection with values of 0.00004 inch (1 micron).

Timing is based on 720 degrees, sinusoidal wave chart outlining cylinder motion, calling out when each valve opens, duration at travel, closes, intake, compression, power, exhaust, fuel direct injection, spark timing.

• • 3. Description—Additional Embodiment. FIG. 3. Upper and Side Coils. This alternative embodiment utilizes an upper coil to provide increased initial pressure to the valve. This is accomplished with increased surface area at the top of the valve.
  • 4. Operation—Additional Embodiment. See Operation of First Embodiment. Operation is the same.

g. Conclusion, Ramifications and Scope

• • A series of high temperature linear actuators with a controller and a computer are used with intake and exhaust valves of an internal combustion engine. This is intended to reduce emissions by utilizing a closed loop feedback system to the system controller from multiple inputs and providing multiple outputs utilizing a Rules Based Software for processing inputs and creating outputs. This invention is intended for green energy related applications where linear actuators with a total engine control system may be utilized for higher engine efficiency and higher gas mileage resulting in reduction of greenhouse emissions. Advantages and applications include all fuel type engines including but not limited to: diesel, natural gas, biofuel, propane and gasoline. There are a number of possible engine applications that can be programmed to optimization. A few applications are emissions optimization, idle duration (default), torque, and horsepower.

This design is not limited to the particular forms shown. There are magnetic alloys that can be developed that possess increased Curie Temperatures to further increase magnetism at higher temperature. Curie Temperature is the temperature at which a magnet begins to lose magnetism. Also other variables can be modified including but not limited to length of valve stem, diameter of valve face, and magnetic coil size and density.

Claims

1: A series of high temperature linear actuators with a controller and a computer are used with intake and exhaust valves of an internal combustion engine. This is intended to reduce emissions by utilizing a closed loop feedback system to the system controller from multiple inputs and providing multiple outputs utilizing a Rules Based Software for processing inputs and creating outputs. This invention is intended for green energy related applications where linear actuators with a total engine control system may be utilized for higher engine efficiency and higher gas mileage resulting in reduction of greenhouse emissions.